Exclusion of a major role for the PTEN tumour-suppressor gene in breast carcinomas

PubMed Central

Freihoff, D; Kempe, A; Beste, B; Wappenschmidt, B; Kreyer, E; Hayashi, Y; Meindl, A; Krebs, D; Wiestler, O D; Deimling, A von; Schmutzler, R K

1999-01-01

PTEN is a novel tumour-suppressor gene located on chromosomal band 10q23.3. This region displays frequent loss of heterozygosity (LOH) in a variety of human neoplasms including breast carcinomas. The detection of PTEN mutations in Cowden disease and in breast carcinoma cell lines suggests that PTEN may be involved in mammary carcinogenesis. We here report a mutational analysis of tumour specimens from 103 primary breast carcinomas and constitutive DNA from 25 breast cancer families. The entire coding region of PTEN was screened by single-strand conformation polymorphism (SSCP) analysis and direct sequencing using intron-based primers. No germline mutations could be identified in the breast cancer families and only one sporadic carcinoma carried a PTEN mutation at one allele. In addition, all sporadic tumours were analysed for homozygous deletions by differential polymerase chain reaction (PCR) and for allelic loss using the microsatellite markers D10S215, D10S564 and D10S573. No homozygous deletions were detected and only 10 out of 94 informative tumours showed allelic loss in the PTEN region. These results suggest that PTEN does not play a major role in breast cancer formation. 1999 Cancer Research Campaign PMID:10070865

History of myeloid-derived suppressor cells.

PubMed

Talmadge, James E; Gabrilovich, Dmitry I

2013-10-01

Tumour-induced granulocytic hyperplasia is associated with tumour vasculogenesis and escape from immunity via T cell suppression. Initially, these myeloid cells were identified as granulocytes or monocytes; however, recent studies have revealed that this hyperplasia is associated with populations of multipotent progenitor cells that have been identified as myeloid-derived suppressor cells (MDSCs). The study of MDSCs has provided a wealth of information regarding tumour pathobiology, has extended our understanding of neoplastic progression and has modified our approaches to immune adjuvant therapy. In this Timeline article, we discuss the history of MDSCs, their influence on tumour progression and metastasis, and the crosstalk between tumour cells, MDSCs and the host macroenvironment.

Role of chromosome 3p12–p21 tumour suppressor genes in clear cell renal cell carcinoma: analysis of VHL dependent and VHL independent pathways of tumorigenesis

PubMed Central

Martinez, A; Fullwood, P; Kondo, K; Kishida, T; Yao, M; Maher, E R; Latif, F

2000-01-01

Aims—Chromosome 3p deletions and loss of heterozygosity (LOH) for 3p markers are features of clear cell renal cell carcinoma but are rare in non-clear cell renal cell carcinoma. The VHL tumour suppressor gene, which maps to 3p25, is a major gatekeeper gene for clear cell renal cell carcinoma and is inactivated in most sporadic cases of this disease. However, it has been suggested that inactivation of other 3p tumour suppressor genes might be crucial for clear cell renal cell carcinoma tumorigenesis, with inactivation (VHL negative) and without inactivation (VHL positive) of the VHL tumour suppressor gene. This study set out to investigate the role of non-VHL tumour suppressor genes in VHL negative and VHL positive clear cell renal cell carcinoma. Methods—Eighty two clear cell renal cell carcinomas of known VHL inactivation status were analysed for LOH at polymorphic loci within the candidate crucial regions for chromosome 3p tumour suppressor genes (3p25, LCTSGR1 at 3p21.3, LCTSGR2 at 3p12 and at 3p14.2). Results—Chromosome 3p12–p21 LOH was frequent both in VHL negative and VHL positive clear cell renal cell carcinoma. However, although the frequency of 3p25 LOH in VHL negative clear cell renal cell carcinoma was similar to that at 3p12–p21, VHL positive tumours demonstrated significantly less LOH at 3p25 than at 3p12–p21. Although there was evidence of LOH for clear cell renal cell carcinoma tumour suppressor genes at 3p21, 3p14.2, and 3p12, both in VHL negative and VHL positive tumours, the major clear cell renal cell carcinoma LOH region mapped to 3p21.3, close to the lung cancer tumour suppressor gene region 1 (LCTSGR1). There was no association between tumour VHL status and tumour grade and stage. Conclusions—These findings further indicate that VHL inactivation is not sufficient to initiate clear cell renal cell carcinoma and that loss of a gatekeeper 3p21 tumour suppressor gene is a crucial event for renal cell carcinoma development in both VHL

E1a is an exogenous in vivo tumour suppressor.

PubMed

Cimas, Francisco J; Callejas-Valera, Juan L; García-Olmo, Dolores C; Hernández-Losa, Javier; Melgar-Rojas, Pedro; Ruiz-Hidalgo, María J; Pascual-Serra, Raquel; Ortega-Muelas, Marta; Roche, Olga; Marcos, Pilar; Garcia-Gil, Elena; Fernandez-Aroca, Diego M; Ramón Y Cajal, Santiago; Gutkind, J Silvio; Sanchez-Prieto, Ricardo

2017-07-28

The E1a gene from adenovirus has become a major tool in cancer research. Since the discovery of E1a, it has been proposed to be an oncogene, becoming a key element in the model of cooperation between oncogenes. However, E1a's in vivo behaviour is consistent with a tumour suppressor gene, due to the block/delay observed in different xenograft models. To clarify this interesting controversy, we have evaluated the effect of the E1a 13s isoform from adenovirus 5 in vivo. Initially, a conventional xenograft approach was performed using previously unreported HCT116 and B16-F10 cells, showing a clear anti-tumour effect regardless of the mouse's immunological background (immunosuppressed/immunocompetent). Next, we engineered a transgenic mouse model in which inducible E1a 13s expression was under the control of cytokeratin 5 to avoid side effects during embryonic development. Our results show that E1a is able to block chemical skin carcinogenesis, showing an anti-tumour effect. The present report demonstrates the in vivo anti-tumour effect of E1a, showing that the in vitro oncogenic role of E1a cannot be extrapolated in vivo, supporting its future use in gene therapy approaches. Copyright © 2017 Elsevier B.V. All rights reserved.

Presence of activating KRAS mutations correlates significantly with expression of tumour suppressor genes DCN and TPM1 in colorectal cancer.

PubMed

Mlakar, Vid; Berginc, Gasper; Volavsek, Metka; Stor, Zdravko; Rems, Miran; Glavac, Damjan

2009-08-13

Despite identification of the major genes and pathways involved in the development of colorectal cancer (CRC), it has become obvious that several steps in these pathways might be bypassed by other as yet unknown genetic events that lead towards CRC. Therefore we wanted to improve our understanding of the genetic mechanisms of CRC development. We used microarrays to identify novel genes involved in the development of CRC. Real time PCR was used for mRNA expression as well as to search for chromosomal abnormalities within candidate genes. The correlation between the expression obtained by real time PCR and the presence of the KRAS mutation was investigated. We detected significant previously undescribed underexpression in CRC for genes SLC26A3, TPM1 and DCN, with a suggested tumour suppressor role. We also describe the correlation between TPM1 and DCN expression and the presence of KRAS mutations in CRC. When searching for chromosomal abnormalities, we found deletion of the TPM1 gene in one case of CRC, but no deletions of DCN and SLC26A3 were found. Our study provides further evidence of decreased mRNA expression of three important tumour suppressor genes in cases of CRC, thus implicating them in the development of this type of cancer. Moreover, we found underexpression of the TPM1 gene in a case of CRCs without KRAS mutations, showing that TPM1 might serve as an alternative path of development of CRC. This downregulation could in some cases be mediated by deletion of the TPM1 gene. On the other hand, the correlation of DCN underexpression with the presence of KRAS mutations suggests that DCN expression is affected by the presence of activating KRAS mutations, lowering the amount of the important tumour suppressor protein decorin.

Presence of activating KRAS mutations correlates significantly with expression of tumour suppressor genes DCN and TPM1 in colorectal cancer

PubMed Central

2009-01-01

Background Despite identification of the major genes and pathways involved in the development of colorectal cancer (CRC), it has become obvious that several steps in these pathways might be bypassed by other as yet unknown genetic events that lead towards CRC. Therefore we wanted to improve our understanding of the genetic mechanisms of CRC development. Methods We used microarrays to identify novel genes involved in the development of CRC. Real time PCR was used for mRNA expression as well as to search for chromosomal abnormalities within candidate genes. The correlation between the expression obtained by real time PCR and the presence of the KRAS mutation was investigated. Results We detected significant previously undescribed underexpression in CRC for genes SLC26A3, TPM1 and DCN, with a suggested tumour suppressor role. We also describe the correlation between TPM1 and DCN expression and the presence of KRAS mutations in CRC. When searching for chromosomal abnormalities, we found deletion of the TPM1 gene in one case of CRC, but no deletions of DCN and SLC26A3 were found. Conclusion Our study provides further evidence of decreased mRNA expression of three important tumour suppressor genes in cases of CRC, thus implicating them in the development of this type of cancer. Moreover, we found underexpression of the TPM1 gene in a case of CRCs without KRAS mutations, showing that TPM1 might serve as an alternative path of development of CRC. This downregulation could in some cases be mediated by deletion of the TPM1 gene. On the other hand, the correlation of DCN underexpression with the presence of KRAS mutations suggests that DCN expression is affected by the presence of activating KRAS mutations, lowering the amount of the important tumour suppressor protein decorin. PMID:19678923

Mutations in the LKB1 tumour suppressor are frequently detected in tumours from Caucasian but not Asian lung cancer patients.

PubMed

Koivunen, J P; Kim, J; Lee, J; Rogers, A M; Park, J O; Zhao, X; Naoki, K; Okamoto, I; Nakagawa, K; Yeap, B Y; Meyerson, M; Wong, K-K; Richards, W G; Sugarbaker, D J; Johnson, B E; Jänne, P A

2008-07-22

Somatic mutations of LKB1 tumour suppressor gene have been detected in human cancers including non-small cell lung cancer (NSCLC). The relationship between LKB1 mutations and clinicopathological characteristics and other common oncogene mutations in NSCLC is inadequately described. In this study we evaluated tumour specimens from 310 patients with NSCLC including those with adenocarcinoma, adenosquamous carcinoma, and squamous cell carcinoma histologies. Tumours were obtained from patients of US (n=143) and Korean (n=167) origin and screened for LKB1, KRAS, BRAF, and EGFR mutations using RT-PCR-based SURVEYOR-WAVE method followed by Sanger sequencing. We detected mutations in the LKB1 gene in 34 tumours (11%). LKB1 mutation frequency was higher in NSCLC tumours of US origin (17%) compared with 5% in NSCLCs of Korean origin (P=0.001). They tended to occur more commonly in adenocarcinomas (13%) than in squamous cell carcinomas (5%) (P=0.066). LKB1 mutations associated with smoking history (P=0.007) and KRAS mutations (P=0.042) were almost mutually exclusive with EGFR mutations (P=0.002). The outcome of stages I and II NSCLC patients treated with surgery alone did not significantly differ based on LKB1 mutation status. Our study provides clinical and molecular characteristics of NSCLC, which harbour LKB1 mutations.

The Role of Suppressors of Cytokine Signalling in Human Neoplasms

PubMed Central

Sharma, Anup K.; Mokbel, Kefah

2014-01-01

Suppressors of cytokine signalling 1–7 (SOCS1–7) and cytokine-inducible SH2-containing protein (CIS) are a group of intracellular proteins that are well known as JAK-STAT and several other signalling pathways negative feedback regulators. More recently several members have been identified as tumour suppressors and dysregulation of their biological roles in controlling cytokine and growth factor signalling may contribute to the development of many solid organ and haematological malignancies. This review explores their biological functions and their possible tumour suppressing role in human neoplasms. PMID:24757565

Oligoamine analogues in combination with 2-difluoromethylornithine synergistically induce re-expression of aberrantly silenced tumour-suppressor genes

PubMed Central

Wu, Yu; Steinbergs, Nora; Murray-Stewart, Tracy; Marton, Laurence J.; Casero, Robert A.

2011-01-01

Epigenetic gene silencing is an important mechanism in the initiation and progression of cancer. Abnormal DNA CpG island hypermethylation and histone modifications are involved in aberrant silencing of tumour-suppressor genes. LSD1 (lysine-specific demethylase 1) was the first enzyme identified to specifically demethylate H3K4 (Lys4 of histone H3). Methylated H3K4 is an important mark associated with transcriptional activation. The flavin adenine dinucleotide-binding amine oxidase domain of LSD1 is homologous with two polyamine oxidases, SMO (spermine oxidase) and APAO (N1-acetylpolyamine oxidase). We have demonstrated previously that long-chain polyamine analogues, the oligoamines, are inhibitors of LSD1. In the present paper we report the synergistic effects of specific oligoamines in combination with DFMO (2-difluoromethylornithine), an inhibitor of ornithine decarboxylase, in human colorectal cancer cells. DFMO treatment depletes natural polyamines and increases the uptake of exogenous polyamines. The combination of oligoamines and DFMO results in a synergistic re-expression of aberrantly silenced tumour-suppressor genes, including SFRP2 (secreted frizzled-related protein 2), which encodes a Wnt signalling pathway antagonist and plays an anti-tumorigenic role in colorectal cancer. The treatment-induced re-expression of SFRP2 is associated with increased H3K4me2 (di-methyl H3K4) in the gene promoter. The combination of LSD1-inhibiting oligoamines and DFMO represents a novel approach to epigenetic therapy of cancer. PMID:22132744

Mutations in the LKB1 tumour suppressor are frequently detected in tumours from Caucasian but not Asian lung cancer patients

PubMed Central

Koivunen, J P; Kim, J; Lee, J; Rogers, A M; Park, J O; Zhao, X; Naoki, K; Okamoto, I; Nakagawa, K; Yeap, B Y; Meyerson, M; Wong, K-K; Richards, W G; Sugarbaker, D J; Johnson, B E; Jänne, P A

2008-01-01

Somatic mutations of LKB1 tumour suppressor gene have been detected in human cancers including non-small cell lung cancer (NSCLC). The relationship between LKB1 mutations and clinicopathological characteristics and other common oncogene mutations in NSCLC is inadequately described. In this study we evaluated tumour specimens from 310 patients with NSCLC including those with adenocarcinoma, adenosquamous carcinoma, and squamous cell carcinoma histologies. Tumours were obtained from patients of US (n=143) and Korean (n=167) origin and screened for LKB1, KRAS, BRAF, and EGFR mutations using RT—PCR-based SURVEYOR-WAVE method followed by Sanger sequencing. We detected mutations in the LKB1 gene in 34 tumours (11%). LKB1 mutation frequency was higher in NSCLC tumours of US origin (17%) compared with 5% in NSCLCs of Korean origin (P=0.001). They tended to occur more commonly in adenocarcinomas (13%) than in squamous cell carcinomas (5%) (P=0.066). LKB1 mutations associated with smoking history (P=0.007) and KRAS mutations (P=0.042) were almost mutually exclusive with EGFR mutations (P=0.002). The outcome of stages I and II NSCLC patients treated with surgery alone did not significantly differ based on LKB1 mutation status. Our study provides clinical and molecular characteristics of NSCLC, which harbour LKB1 mutations. PMID:18594528

Promoter Hypermethylation of Tumour Suppressor Genes as Potential Biomarkers in Colorectal Cancer

PubMed Central

Ng, Jennifer Mun-Kar; Yu, Jun

2015-01-01

Colorectal cancer (CRC) is a common malignancy and the fourth leading cause of cancer deaths worldwide. It results from the accumulation of multiple genetic and epigenetic changes leading to the transformation of colon epithelial cells into invasive adenocarcinomas. In CRC, epigenetic changes, in particular promoter CpG island methylation, occur more frequently than genetic mutations. Hypermethylation contributes to carcinogenesis by inducing transcriptional silencing or downregulation of tumour suppressor genes and currently, over 600 candidate hypermethylated genes have been identified. Over the past decade, a deeper understanding of epigenetics coupled with technological advances have hinted at the potential of translating benchtop research into biomarkers for clinical use. DNA methylation represents one of the largest bodies of literature in epigenetics, and hence has the highest potential for minimally invasive biomarker development. Most progress has been made in the development of diagnostic markers and there are currently two, one stool-based and one blood-based, biomarkers that are commercially available for diagnostics. Prognostic and predictive methylation markers are still at their infantile stages. PMID:25622259

Nuclear factor one B (NFIB) encodes a subtype-specific tumour suppressor in glioblastoma

PubMed Central

Stringer, Brett W.; Bunt, Jens; Day, Bryan W.; Barry, Guy; Jamieson, Paul R.; Ensbey, Kathleen S.; Bruce, Zara C.; Goasdoué, Kate; Vidal, Hélène; Charmsaz, Sara; Smith, Fiona M.; Cooper, Leanne T.; Piper, Michael

2016-01-01

Glioblastoma (GBM) is an essentially incurable and rapidly fatal cancer, with few markers predicting a favourable prognosis. Here we report that the transcription factor NFIB is associated with significantly improved survival in GBM. NFIB expression correlates inversely with astrocytoma grade and is lowest in mesenchymal GBM. Ectopic expression of NFIB in low-passage, patient-derived classical and mesenchymal subtype GBM cells inhibits tumourigenesis. Ectopic NFIB expression activated phospho-STAT3 signalling only in classical and mesenchymal GBM cells, suggesting a mechanism through which NFIB may exert its context-dependent tumour suppressor activity. Finally, NFIB expression can be induced in GBM cells by drug treatment with beneficial effects. PMID:27083054

Cancer genes mutation profiling in calcifying epithelial odontogenic tumour.

PubMed

de Sousa, Sílvia Ferreira; Diniz, Marina Gonçalves; França, Josiane Alves; Fontes Pereira, Thaís Dos Santos; Moreira, Rennan Garcias; Santos, Jean Nunes Dos; Gomez, Ricardo Santiago; Gomes, Carolina Cavalieri

2018-03-01

To identify calcifying epithelial odontogenic tumour (CEOT) mutations in oncogenes and tumour suppressor genes. A panel of 50 genes commonly mutated in cancer was sequenced in CEOT by next-generation sequencing. Sanger sequencing was used to cover the region of the frameshift deletion identified in one sample. Missense single nucleotide variants (SNVs) with minor allele frequency (MAF) <1% were detected in PTEN , MET and JAK3 . A frameshift deletion in CDKN2A occurred in association with a missense mutation in the same gene region, suggesting a second hit in the inactivation of this gene. APC, KDR, KIT, PIK3CA and TP53 missense SNVs were identified; however, these are common SNVs, showing MAF >1%. CEOT harbours mutations in the tumour suppressor PTEN and CDKN2A and in the oncogenes JAK3 and MET . As these mutations occurred in only one case each, they are probably not driver mutations for these tumours. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Sepsis-induced expansion of granulocytic myeloid-derived suppressor cells promotes tumour growth through Toll-like receptor 4.

PubMed

Llitjos, Jean-François; Auffray, Cédric; Alby-Laurent, Fanny; Rousseau, Christophe; Merdji, Hamid; Bonilla, Nelly; Toubiana, Julie; Belaïdouni, Nadia; Mira, Jean-Paul; Lucas, Bruno; Chiche, Jean-Daniel; Pène, Frédéric

2016-08-01

Severe sepsis remains a frequent and dreaded complication in cancer patients. Beyond the often fatal short-term outcome, the long-term sequelae of severe sepsis may also impact directly on the prognosis of the underlying malignancy in survivors. The immune system is involved in all stages of tumour development, in the detection of transforming and dying cells and in the prevention of tumour growth and dissemination. In fact, the profound and sustained immune defects induced by sepsis may constitute a privileged environment likely to favour tumour growth. We investigated the impact of sepsis on malignant tumour growth in a double-hit animal model of polymicrobial peritonitis, followed by subcutaneous inoculation of MCA205 fibrosarcoma cells. As compared to their sham-operated counterparts, post-septic mice exhibited accelerated tumour growth. This was associated with intratumoural accumulation of CD11b(+) Ly6G(high) polymorphonuclear cells (PMNs) that could be characterized as granulocytic myeloid-derived suppressor cells (G-MDSCs). Depletion of granulocytic cells in post-septic mice inhibited the sepsis-enhanced tumour growth. Toll-like receptor (TLR)-4 (Tlr4) and Myd88 deficiencies prevented sepsis-induced expansion of G-MDSCs and tumour growth. Our results demonstrate that the myelosuppressive environment induced by severe bacterial infections promotes malignant tumour growth, and highlight a critical role of CD11b(+) Ly6G(high) G-MDSCs under the control of TLR-dependent signalling. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Oncogenic functions of tumour suppressor p21(Waf1/Cip1/Sdi1): association with cell senescence and tumour-promoting activities of stromal fibroblasts.

PubMed

Roninson, Igor B

2002-05-08

p21(Waf1/Cip1/Sdi1) is best known as a broad-specificity inhibitor of cyclin/cyclin-dependent kinase complexes, but p21 also interacts with many other regulators of transcription or signal transduction. p21 induction, which is mediated by p53 and by p53-independent mechanisms, is essential for the onset of cell cycle arrest in damage response and cell senescence. The effects of p21 knockout in mice and its expression patterns in human cancer are consistent with a role for p21 as both a tumour suppressor and an oncogene. Several functions of p21 are likely to promote carcinogenesis and tumour progression. These include endoreduplication and abnormal mitosis that develop in tumour cells after release from p21-induced growth arrest, the ability of p21 to inhibit apoptosis through several different mechanisms, and its ability to stimulate transcription of secreted factors with mitogenic and anti-apoptotic activities. The latter effects of p21 show close resemblance to paracrine activities of senescent cells and to tumour-promoting functions of stromal fibroblasts. Therapeutic strategies targeting the oncogenic consequences of p21 expression may provide a new approach to chemoprevention and treatment of cancer.

Prognostic significance of downregulated expression of the candidate tumour suppressor gene SASH1 in colon cancer.

PubMed

Rimkus, C; Martini, M; Friederichs, J; Rosenberg, R; Doll, D; Siewert, J R; Holzmann, B; Janssen, K P

2006-11-20

The gene SASH1 (SAM- and SH3-domain containing 1) has originally been identified as a candidate tumour suppressor gene in breast cancer. SASH1 is a member of the SH3-domain containing expressed in lymphocytes (SLY1) gene family that encodes signal adapter proteins composed of several protein-protein interaction domains. The other members of this family are expressed mainly in haematopoietic cells, whereas SASH1 shows ubiquitous expression. We have used quantitative real-time PCR to investigate the expression of SASH1 in tissue samples from 113 patients with colon carcinoma, and compared the expression with 15 normal colon tissue samples. Moreover, nine benign adenomas and 10 liver metastases were analysed. Expression levels of SASH1 were strongly and significantly reduced in colon cancer of UICC stage II, III, and IV, as well as in liver metastases. Moreover, SASH1 was also found to be downregulated on protein levels by immunoblot analysis. However, SASH1 expression was not significantly deregulated in precancerous adenomas and in earlier stage lesions (UICC I). Overall, 48 out of 113 primary colon tumours showed SASH1 expression that was at least 10-fold lower than the levels found in normal colon tissue. Downregulation of SASH1 expression was correlated with the formation of metachronous distant metastasis, and multivariate analysis identified SASH1 downregulation as an independent negative prognostic parameter for patient survival. This study demonstrates for the first time that expression of a member of the SLY1-gene family has prognostic significance in human cancer.

Prognostic significance of downregulated expression of the candidate tumour suppressor gene SASH1 in colon cancer

PubMed Central

Rimkus, C; Martini, M; Friederichs, J; Rosenberg, R; Doll, D; Siewert, J R; Holzmann, B; Janssen, K P

2006-01-01

The gene SASH1 (SAM- and SH3-domain containing 1) has originally been identified as a candidate tumour suppressor gene in breast cancer. SASH1 is a member of the SH3-domain containing expressed in lymphocytes (SLY1) gene family that encodes signal adapter proteins composed of several protein–protein interaction domains. The other members of this family are expressed mainly in haematopoietic cells, whereas SASH1 shows ubiquitous expression. We have used quantitative real-time PCR to investigate the expression of SASH1 in tissue samples from 113 patients with colon carcinoma, and compared the expression with 15 normal colon tissue samples. Moreover, nine benign adenomas and 10 liver metastases were analysed. Expression levels of SASH1 were strongly and significantly reduced in colon cancer of UICC stage II, III, and IV, as well as in liver metastases. Moreover, SASH1 was also found to be downregulated on protein levels by immunoblot analysis. However, SASH1 expression was not significantly deregulated in precancerous adenomas and in earlier stage lesions (UICC I). Overall, 48 out of 113 primary colon tumours showed SASH1 expression that was at least 10-fold lower than the levels found in normal colon tissue. Downregulation of SASH1 expression was correlated with the formation of metachronous distant metastasis, and multivariate analysis identified SASH1 downregulation as an independent negative prognostic parameter for patient survival. This study demonstrates for the first time that expression of a member of the SLY1-gene family has prognostic significance in human cancer. PMID:17088907

Akt phosphorylation regulates the tumour-suppressor merlin through ubiquitination and degradation.

PubMed

Tang, Xiaoling; Jang, Sung-Wuk; Wang, Xuerong; Liu, Zhixue; Bahr, Scott M; Sun, Shi-Yong; Brat, Daniel; Gutmann, David H; Ye, Keqiang

2007-10-01

The neurofibromatosis-2 (NF2) tumour-suppressor gene encodes an intracellular membrane-associated protein, called merlin, whose growth-suppressive function is dependent on its ability to form interactions through its intramolecular amino-terminal domain (NTD) and carboxy-terminal domain (CTD). Merlin phosphorylation plays a critical part in dictating merlin NTD/CTD interactions as well as in controlling binding to its effector proteins. Merlin is partially regulated by phosphorylation of Ser 518, such that hyperphosphorylated merlin is inactive and fails to form productive intramolecular and intermolecular interactions. Here, we show that the protein kinase Akt directly binds to and phosphorylates merlin on residues Thr 230 and Ser 315, which abolishes merlin NTD/CTD interactions and binding to merlin's effector protein PIKE-L and other binding partners. Furthermore, Akt-mediated phosphorylation leads to merlin degradation by ubiquitination. These studies demonstrate that Akt-mediated merlin phosphorylation regulates the function of merlin in the absence of an inactivating mutation.

The role of the RB tumour suppressor pathway in oxidative stress responses in the haematopoietic system

PubMed Central

Macleod, Kay F.

2010-01-01

Exposure to pro-oxidants and defects in the repair of oxidative base damage are associated with disease and ageing and also contribute to the development of anaemia, bone marrow failure and haematopoietic malignancies. This Review assesses emerging data indicative of a specific role for the RB tumour suppressor pathway in the response of the haematopoietic system to oxidative stress. This is mediated through signalling pathways that involve DNA damage sensors, forkhead box O (Foxo) transcription factors and p38 mitogen-activated protein kinases and has downstream consequences for cell cycle progression, antioxidant capacity, mitochondrial mass and cellular metabolism. PMID:18800074

Frequent genomic imbalances suggest commonly altered tumour genes in human hepatocarcinogenesis

PubMed Central

Niketeghad, F; Decker, H J; Caselmann, W H; Lund, P; Geissler, F; Dienes, H P; Schirmacher, P

2001-01-01

Hepatocellular carcinoma (HCC) is one of the most frequent-occurring malignant tumours worldwide, but molecular changes of tumour DNA, with the exception of viral integrations and p53 mutations, are poorly understood. In order to search for common macro-imbalances of genomic tumour DNA, 21 HCCs and 3 HCC-cell lines were characterized by comparative genomic hybridization (CGH), subsequent database analyses and in selected cases by fluorescence in situ hybridization (FISH). Chromosomal subregions of 1q, 8q, 17q and 20q showed frequent gains of genomic material, while losses were most prevalent in subregions of 4q, 6q, 13q and 16q. Deleted regions encompass tumour suppressor genes, like RB-1 and the cadherin gene cluster, some of them previously identified as potential target genes in HCC development. Several potential growth- or transformation-promoting genes located in chromosomal subregions showed frequent gains of genomic material. The present study provides a basis for further genomic and expression analyses in HCCs and in addition suggests chromosome 4q to carry a so far unidentified tumour suppressor gene relevant for HCC development. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11531255

PU.1 is a major transcriptional activator of the tumour suppressor gene LIMD1

PubMed Central

Foxler, Daniel E.; James, Victoria; Shelton, Samuel J.; Vallim, Thomas Q. de A.; Shaw, Peter E.; Sharp, Tyson V.

2011-01-01

LIMD1 is a tumour suppressor gene (TSG) down regulated in ∼80% of lung cancers with loss also demonstrated in breast and head and neck squamous cell carcinomas. LIMD1 is also a candidate TSG in childhood acute lymphoblastic leukaemia. Mechanistically, LIMD1 interacts with pRB, repressing E2F-driven transcription as well as being a critical component of microRNA-mediated gene silencing. In this study we show a CpG island within the LIMD1 promoter contains a conserved binding motif for the transcription factor PU.1. Mutation of the PU.1 consensus reduced promoter driven transcription by 90%. ChIP and EMSA analysis demonstrated that PU.1 specifically binds to the LIMD1 promoter. siRNA depletion of PU.1 significantly reduced endogenous LIMD1 expression, demonstrating that PU.1 is a major transcriptional activator of LIMD1. PMID:21402070

Frequent silencing of RASSF1A by DNA methylation in thymic neuroendocrine tumours.

PubMed

Kajiura, Koichiro; Takizawa, Hiromitsu; Morimoto, Yuki; Masuda, Kiyoshi; Tsuboi, Mitsuhiro; Kishibuchi, Reina; Wusiman, Nuliamina; Sawada, Toru; Kawakita, Naoya; Toba, Hiroaki; Yoshida, Mitsuteru; Kawakami, Yukikiyo; Naruto, Takuya; Imoto, Issei; Tangoku, Akira; Kondo, Kazuya

2017-09-01

Aberrant methylation of promoter CpG islands (CGIs) of tumour suppressor genes is a common epigenetic mechanism underlying cancer pathogenesis. The methylation patterns of thymic tumours have not been studied in detail since such tumours are rare. Herein, we sought to identify genes that could serve as epigenetic targets for thymic neuroendocrine tumour (NET) therapy. Genome-wide screening for aberrantly methylated CGIs was performed in three NET samples, seven thymic carcinoma (TC) samples, and eight type-B3 thymoma samples. The methylation status of thymic epithelial tumours (TETs) samples was validated by pyrosequencing in a larger cohort. The expression status was analysed by quantitative polymerase chain reaction (PCR) and immunohistochemistry. We identified a CGI on a novel gene, RASSF1A, which was strongly hypermethylated in NET, but not in thymic carcinoma or B3 thymoma. RASSF1A was identified as a candidate gene statistically and bibliographically, as it showed frequent CGI hypermethylation in NET by genome-wide screening. Pyrosequencing confirmed significant hypermethylation of a RASSF1A CGI in NET. Low-grade NET tissue was more strongly methylated than high-grade NET. Quantitative PCR and immunohistochemical staining revealed that RASSF1A mRNA and protein expression levels were negatively regulated by DNA methylation. RASSF1A is a tumour suppressor gene epigenetically dysregulated in NET. Aberrant methylation of RASSF1A has been reported in various tumours, but this is the first report of RASSF1A hypermethylation in TETs. RASSF1A may represent an epigenetic therapeutic target in thymic NET. Copyright © 2017 Elsevier B.V. All rights reserved.

Methylator phenotype of malignant germ cell tumours in children identifies strong candidates for chemotherapy resistance

PubMed Central

Jeyapalan, J N; Noor, D A Mohamed; Lee, S-H; Tan, C L; Appleby, V A; Kilday, J P; Palmer, R D; Schwalbe, E C; Clifford, S C; Walker, D A; Murray, M J; Coleman, N; Nicholson, J C; Scotting, P J

2011-01-01

Background: Yolk sac tumours (YSTs) and germinomas are the two major pure histological subtypes of germ cell tumours. To date, the role of DNA methylation in the aetiology of this class of tumour has only been analysed in adult testicular forms and with respect to only a few genes. Methods: A bank of paediatric tumours was analysed for global methylation of LINE-1 repeat elements and global methylation of regulatory elements using GoldenGate methylation arrays. Results: Both germinomas and YSTs exhibited significant global hypomethylation of LINE-1 elements. However, in germinomas, methylation of gene regulatory regions differed little from control samples, whereas YSTs exhibited increased methylation at a large proportion of the loci tested, showing a ‘methylator' phenotype, including silencing of genes associated with Caspase-8-dependent apoptosis. Furthermore, we found that the methylator phenotype of YSTs was coincident with higher levels of expression of the DNA methyltransferase, DNA (cytosine-5)-methyltransferase 3B, suggesting a mechanism underlying the phenotype. Conclusion: Epigenetic silencing of a large number of potential tumour suppressor genes in YSTs might explain why they exhibit a more aggressive natural history than germinomas and silencing of genes associated with Caspase-8-dependent cell death might explain the relative resistance of YSTs to conventional therapy. PMID:21712824

Methylator phenotype of malignant germ cell tumours in children identifies strong candidates for chemotherapy resistance.

PubMed

Jeyapalan, J N; Noor, D A Mohamed; Lee, S-H; Tan, C L; Appleby, V A; Kilday, J P; Palmer, R D; Schwalbe, E C; Clifford, S C; Walker, D A; Murray, M J; Coleman, N; Nicholson, J C; Scotting, P J

2011-08-09

Yolk sac tumours (YSTs) and germinomas are the two major pure histological subtypes of germ cell tumours. To date, the role of DNA methylation in the aetiology of this class of tumour has only been analysed in adult testicular forms and with respect to only a few genes. A bank of paediatric tumours was analysed for global methylation of LINE-1 repeat elements and global methylation of regulatory elements using GoldenGate methylation arrays. Both germinomas and YSTs exhibited significant global hypomethylation of LINE-1 elements. However, in germinomas, methylation of gene regulatory regions differed little from control samples, whereas YSTs exhibited increased methylation at a large proportion of the loci tested, showing a 'methylator' phenotype, including silencing of genes associated with Caspase-8-dependent apoptosis. Furthermore, we found that the methylator phenotype of YSTs was coincident with higher levels of expression of the DNA methyltransferase, DNA (cytosine-5)-methyltransferase 3B, suggesting a mechanism underlying the phenotype. Epigenetic silencing of a large number of potential tumour suppressor genes in YSTs might explain why they exhibit a more aggressive natural history than germinomas and silencing of genes associated with Caspase-8-dependent cell death might explain the relative resistance of YSTs to conventional therapy.

Novel p53 tumour suppressor mutations in cases of spindle cell sarcoma, pleomorphic sarcoma and fibrosarcoma in cats.

PubMed

Mayr, B; Reifinger, M; Alton, K; Schaffner, G

1998-06-01

Twenty feline neoplasms were sequenced in the region from exons 5 to 8 for the presence of tumour suppressor gene p53 mutations. In a spindle cell sarcoma of the bladder, a missense mutation (codon 164 AAG-->GAG, lysine-->glutamic acid) in exon 5 was detected. In a pleomorphic sarcoma, a 23 bp deletion involving the splicing junction between intron 5 and exon 6 was observed. In a fibrosarcoma, a 6 bp deletion of p53 covering 2 bp of exon 7 and 4 bp of intron 7, including the splicing junction, was found. The study demonstrates three new p53 mutations in different types of sarcomas in cats.

The novel 19q13 KRAB zinc-finger tumour suppressor ZNF382 is frequently methylated in oesophageal squamous cell carcinoma and antagonises Wnt/β-catenin signalling.

PubMed

Zhang, Chong; Xiang, Tingxiu; Li, Shuman; Ye, Lin; Feng, Yixiao; Pei, Lijiao; Li, Lili; Wang, Xiangyu; Sun, Ran; Tao, Qian; Ren, Guosheng

2018-05-14

Zinc finger proteins (ZFPs) are the largest transcription factor family in mammals. About one-third of ZFPs are Krüppel-associated box domain (KRAB)-ZFPs and involved in the regulation of cell differentiation/proliferation/apoptosis and neoplastic transformation. We recently identified ZNF382 as a novel KRAB-ZFP epigenetically inactivated in multiple cancers due to frequent promoter CpG methylation. However, its epigenetic alterations, biological functions/mechanism and clinical significance in oesophageal squamous cell carcinoma (ESCC) are still unknown. Here, we demonstrate that ZNF382 expression was suppressed in ESCC due to aberrant promoter methylation, but highly expressed in normal oesophagus tissues. ZNF382 promoter methylation is correlated with ESCC differentiation levels. Restoration of ZNF382 expression in silenced ESCC cells suppressed tumour cell proliferation and metastasis through inducing cell apoptosis. Importantly, ZNF382 suppressed Wnt/β-catenin signalling and downstream target gene expression, likely through binding directly to FZD1 and DVL2 promoters. In summary, our findings demonstrate that ZNF382 functions as a bona fide tumour suppressor inhibiting ESCC pathogenesis through inhibiting the Wnt/β-catenin signalling pathway.

PCDH20 functions as a tumour-suppressor gene through antagonizing the Wnt/β-catenin signalling pathway in hepatocellular carcinoma

PubMed Central

Lv, J; Zhu, P; Yang, Z; Li, M; Zhang, X; Cheng, J; Chen, X; Lu, F

2015-01-01

Several members of protocadherins have been found involved in human carcinogenesis, but little is known about PCDH20 in HCC. Here in this study, using quantitative real-time RT-PCR assay, we demonstrated the downregulation of PCDH20 expression in 6 of 7 HCC cell lines tested. Similarly, PCDH20 expression in primary HCC tissues was also significantly downregulated in comparison with that in either disease-free normal liver tissues or the adjacent nontumour liver tissues (P < 0.001, respectively). Among HCC tumour tissues studied, about 48% (51/107) of them showed reduced PCDH20 mRNA level. Further statistic analysis revealed that the reduced PCDH20 mRNA level in tumour tissues was much more common in younger patients group (aged <50 years) than that in older group (≥50 years) (60% vs 33%, P = 0.0303). Loss of heterozygosity (LOH) and promoter hypermethylation analysis revealed that deletion and/or aberrant epigenetic modulation of PCDH20 gene account for its downregulation, at least in a fraction of tumour specimens. Moreover, ectopic expression of PCDH20 in HCC cells significantly suppressed cell proliferation, clonogenicity, migration and tumour formation. Notably, we proved for the first time that, via activating GSK-3β, PCDH20 could inhibit Wnt/β-catenin signalling pathway. Furthermore, our data suggest that PCDH20 may conduct its Wnt/β-catenin signalling antagonizing function through suppressing Akt and Erk activities and promoting GSK-3β signalling activities. However, the detailed mechanism remained undiscovered. In conclusion, our data here strongly suggested that PCDH20 may act as a candidate tumour suppressor in HCC. PMID:24910204

MDGA2 is a novel tumour suppressor cooperating with DMAP1 in gastric cancer and is associated with disease outcome.

PubMed

Wang, Kunning; Liang, Qiaoyi; Li, Xiaoxing; Tsoi, Ho; Zhang, Jingwan; Wang, Hua; Go, Minnie Y Y; Chiu, Philip W Y; Ng, Enders K W; Sung, Joseph J Y; Yu, Jun

2016-10-01

Using the promoter methylation assay, we have shown that MDGA2 (MAM domain containing glycosylphosphatidylinositol anchor 2) is preferentially methylated in gastric cancer. We analysed its biological effects and prognostic significance in gastric cancer. MDGA2 methylation status was evaluated by combined bisulfite restriction analysis and bisulfite genomic sequencing. The effects of MDGA2 re-expression or knockdown on cell proliferation, apoptosis and the cell cycle were determined. MDGA2 interacting protein was identified by mass spectrometry and MDGA2-related cancer pathways by reporter activity and PCR array analyses. The clinical impact of MDGA2 was assessed in 218 patients with gastric cancer. MDGA2 was commonly silenced in gastric cancer cells (10/11) and primary gastric cancers due to promoter hypermethylation. MDGA2 significantly inhibited cell proliferation by causing G1-S cell cycle arrest and inducing cell apoptosis in vitro, and suppressed xenograft tumour growth in both subcutaneous and orthotopic xenograft mouse models (both p<0.001). The anti-tumorigenic effect of MDGA2 was mediated through direct stabilising of DNA methyltransferase 1 associated protein 1 (DMAP1), which played a tumour suppressive role in gastric cancer. This interaction activated their downstream key elements of p53/p21 signalling cascades. Moreover, promoter methylation of MDGA2 was detected in 62.4% (136/218) of gastric cancers. Multivariate analysis showed that patients with MDGA2 hypermethylation had a significantly decreased survival (p=0.005). Kaplan-Meier survival curves showed that MDGA2 hypermethylation was significantly associated with shortened survival in patients with early gastric cancer. MDGA2 is a critical tumour suppressor in gastric carcinogenesis; its hypermethylation is an independent prognostic factor in patients with gastric cancer. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

MDGA2 is a novel tumour suppressor cooperating with DMAP1 in gastric cancer and is associated with disease outcome

PubMed Central

Wang, Kunning; Liang, Qiaoyi; Li, Xiaoxing; Tsoi, Ho; Zhang, Jingwan; Wang, Hua; Go, Minnie Y Y; Chiu, Philip W Y; Ng, Enders K W; Sung, Joseph J Y; Yu, Jun

2016-01-01

Background Using the promoter methylation assay, we have shown that MDGA2 (MAM domain containing glycosylphosphatidylinositol anchor 2) is preferentially methylated in gastric cancer. We analysed its biological effects and prognostic significance in gastric cancer. Methods MDGA2 methylation status was evaluated by combined bisulfite restriction analysis and bisulfite genomic sequencing. The effects of MDGA2 re-expression or knockdown on cell proliferation, apoptosis and the cell cycle were determined. MDGA2 interacting protein was identified by mass spectrometry and MDGA2-related cancer pathways by reporter activity and PCR array analyses. The clinical impact of MDGA2 was assessed in 218 patients with gastric cancer. Results MDGA2 was commonly silenced in gastric cancer cells (10/11) and primary gastric cancers due to promoter hypermethylation. MDGA2 significantly inhibited cell proliferation by causing G1–S cell cycle arrest and inducing cell apoptosis in vitro, and suppressed xenograft tumour growth in both subcutaneous and orthotopic xenograft mouse models (both p<0.001). The anti-tumorigenic effect of MDGA2 was mediated through direct stabilising of DNA methyltransferase 1 associated protein 1 (DMAP1), which played a tumour suppressive role in gastric cancer. This interaction activated their downstream key elements of p53/p21 signalling cascades. Moreover, promoter methylation of MDGA2 was detected in 62.4% (136/218) of gastric cancers. Multivariate analysis showed that patients with MDGA2 hypermethylation had a significantly decreased survival (p=0.005). Kaplan–Meier survival curves showed that MDGA2 hypermethylation was significantly associated with shortened survival in patients with early gastric cancer. Conclusions MDGA2 is a critical tumour suppressor in gastric carcinogenesis; its hypermethylation is an independent prognostic factor in patients with gastric cancer. PMID:26206665

The two single nucleotide polymorphisms in the H37/RBM5 tumour suppressor gene at 3p21.3 correlated with different subtypes of non-small cell lung cancers

PubMed Central

Oh, Juliana J.; Koegel, Ashley; Phan, Diana T.; Razfar, Ali; Slamon, Dennis J.

2007-01-01

Summary Allele loss and genetic alteration in chromosome 3p, particularly in 3p21.3 region, are the most frequent and the earliest genomic abnormalities found in lung cancer. Multiple 3p21.3 genes exhibit various degrees of tumour suppression activity suggesting that 3p21.3 genes may function as an integrated tumour suppressor region through their diverse biological activities. We have previously demonstrated growth inhibitory effects and tumour suppression mechanism of the H37/RBM5 gene which is one of the 19 genes residing in the 370kb minimal overlap region at 3p21.3. In the current study, in an attempt to find, if any, mutations in the H37 coding region in lung cancer cells, we compared nucleotide sequences of the entire H37 gene in tumour vs. adjacent normal tissues from 17 non-small cell lung cancer (NSCLC) patients. No mutations were detected, instead, we found the two silent single nucleotide polymorphisms (SNPs), C1138T and C2185T, within the coding region of the H37 gene. In addition, we found that specific allele types at these SNP positions are correlated with different histological subtypes of NSCLC; tumours containing heterozygous alleles (C+T) at these SNP positions are more likely to be associated with adenocarcinoma (AC) whereas homozygous alleles (either C or T) are associated with squamous cell carcinoma (SCC) (p=0.0098). We postulate that, these two silent polymorphisms may be in linkage disequilibrium (LD) with a disease causative allele in the 3p21.3 tumour suppressor region which is packed with a large number of important genes affecting lung cancer development. In addition, because of prevalent loss of heterozygosity (LOH) detected at 3p21.3 which precedes lung cancer initiation, these SNPs may be developed into a marker screening for the high risk individuals. PMID:17606309

A Novel Plasmid-Based Microarray Screen Identifies Suppressors of rrp6Δ in Saccharomyces cerevisiae▿†

PubMed Central

Abruzzi, Katharine; Denome, Sylvia; Olsen, Jens Raabjerg; Assenholt, Jannie; Haaning, Line Lindegaard; Jensen, Torben Heick; Rosbash, Michael

2007-01-01

Genetic screens in Saccharomyces cerevisiae provide novel information about interacting genes and pathways. We screened for high-copy-number suppressors of a strain with the gene encoding the nuclear exosome component Rrp6p deleted, with either a traditional plate screen for suppressors of rrp6Δ temperature sensitivity or a novel microarray enhancer/suppressor screening (MES) strategy. MES combines DNA microarray technology with high-copy-number plasmid expression in liquid media. The plate screen and MES identified overlapping, but also different, suppressor genes. Only MES identified the novel mRNP protein Nab6p and the tRNA transporter Los1p, which could not have been identified in a traditional plate screen; both genes are toxic when overexpressed in rrp6Δ strains at 37°C. Nab6p binds poly(A)+ RNA, and the functions of Nab6p and Los1p suggest that mRNA metabolism and/or protein synthesis are growth rate limiting in rrp6Δ strains. Microarray analyses of gene expression in rrp6Δ strains and a number of suppressor strains support this hypothesis. PMID:17101774

O-mannosylation and N-glycosylation: two coordinated mechanisms regulating the tumour suppressor functions of E-cadherin in cancer

PubMed Central

Bartels, Markus F.; Miyoshi, Eiji; Pierce, Michael; Taniguchi, Naoyuki; Carneiro, Fátima; Seruca, Raquel; Reis, Celso A.; Strahl, Sabine; Pinho, Salomé S.

2016-01-01

Dysregulation of tumor suppressor protein E-cadherin is an early molecular event in cancer. O-mannosylation profile of E-cadherin is a newly-described post-translational modification crucial for its adhesive functions in homeostasis. However, the role of O-mannosyl glycans in E-cadherin-mediated cell adhesion in cancer and their interplay with N-glycans remains largely unknown. We herein demonstrated that human gastric carcinomas exhibiting a non-functional E-cadherin display a reduced expression of O-mannosyl glycans concomitantly with increased modification with branched complex N-glycans. Accordingly, overexpression of MGAT5-mediated branched N-glycans both in gastric cancer cells and transgenic mice models led to a significant decrease of O-mannosyl glycans attached to E-cadherin that was associated with impairment of its tumour suppressive functions. Importantly, overexpression of protein O-mannosyltransferase 2 (POMT2) induced a reduced expression of branched N-glycans which led to a protective effect of E-cadherin biological functions. Overall, our results reveal a newly identified mechanism of (dys)regulation of E-cadherin that occur through the interplay between O-mannosylation and N-glycosylation pathway. PMID:27533452

ERK5 pathway regulates the phosphorylation of tumour suppressor hDlg during mitosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inesta-Vaquera, Francisco A.; Campbell, David G.; Arthur, J. Simon C.

2010-08-13

Research highlights: {yields} hDlg is phosphorylated during mitosis in multiple residues. {yields} Prospho-hDlg is excluded from the midbody during mitosis. {yields} hDlg is not phosphorylated by p38{gamma} or JNK1/2 during mitosis. {yields} ERK5 pathway mediates hDlg phosphorylation in mitosis. -- Abstract: Human disc-large (hDlg) is a scaffold protein critical for the maintenance of cell polarity and adhesion. hDlg is thought to be a tumour suppressor that regulates the cell cycle and proliferation. However, the mechanism and pathways involved in hDlg regulation during these processes is still unclear. Here we report that hDlg is phosphorylated during mitosis, and we establish themore » identity of at least three residues phosphorylated in hDlg; some are previously unreported. Phosphorylation affects hDlg localisation excluding it from the contact point between the two daughter cells. Our results reveal a previously unreported pathway for hDlg phosphorylation in mitosis and show that ERK5 pathway mediates hDlg cell cycle dependent phosphorylation. This is likely to have important implications in the correct timely mitotic entry and mitosis progression.« less

MicroRNA-129-1 acts as tumour suppressor and induces cell cycle arrest of GBM cancer cells through targeting IGF2BP3 and MAPK1.

PubMed

Kouhkan, Fatemeh; Mobarra, Naser; Soufi-Zomorrod, Mina; Keramati, Farid; Hosseini Rad, Seyed Mohammad Ali; Fathi-Roudsari, Mehrnoosh; Tavakoli, Rezvan; Hajarizadeh, Athena; Ziaei, Said; Lahmi, Reyhaneh; Hanif, Hamed; Soleimani, Masoud

2016-01-01

MicroRNA-129-1 (miR-129-1) seems to behave as a tumour suppressor since its decreased expression is associated with different tumours such as glioblastoma multiforme (GBM). GBM is the most common form of brain tumours originating from glial cells. The impact of miR-129-1 downregulation on GBM pathogenesis has yet to be elucidated. MiR-129-1 was overexpressed in GBM cells, and its effect on proliferation was investigated by cell cycle assay. MiR-129-1 predicted targets (CDK6, IGF1, HDAC2, IGF2BP3 and MAPK1) were also evaluated by western blot and luciferase assay. Restoration of miR-129-1 reduced cell proliferation and induced G1 accumulation, significantly. Several functional assays confirmed IGF2BP3, MAPK1 and CDK6 as targets of miR-129-1. Despite the fact that IGF1 expression can be suppressed by miR-129-1, through 3'-untranslated region complementary sequence, we could not find any association between IGF1 expression and GBM. MiR-129-1 expression inversely correlates with CDK6, IGF2BP3 and MAPK1 in primary clinical samples. This is the first study to propose miR129-1 as a negative regulator of IGF2BP3 and MAPK1 and also a cell cycle arrest inducer in GBM cells. Our data suggests miR-129-1 as a potential tumour suppressor and presents a rationale for the use of miR-129-1 as a novel strategy to improve treatment response in GBM. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

The 3p14.2 tumour suppressor ADAMTS9 is inactivated by promoter CpG methylation and inhibits tumour cell growth in breast cancer.

PubMed

Shao, Bianfei; Feng, Yixiao; Zhang, Hongbin; Yu, Fang; Li, Qianqian; Tan, Cui; Xu, Hongying; Ying, Jianming; Li, Lili; Yang, Dejuan; Peng, Weiyan; Tang, Jun; Li, Shuman; Ren, Guosheng; Tao, Qian; Xiang, Tingxiu

2018-02-01

Chromosome region 3p12-14 is an important tumour suppressor gene (TSG) locus for multiple cancers. ADAMTS9, a member of the metalloprotease large family, has been identified as a candidate 3p14.2 TSG inactivated by aberrant promoter CpG methylation in several carcinomas, but little known about its expression and function in breast cancer. In this report, ADAMTS9 expression and methylation was analysed in breast cancer cell lines and tissue samples. ADAMTS9 RNA was significantly down-regulated in breast cancer cell lines (6/8). After treating the cells with demethylation agent Aza and TSA, ADAMTS9 expression was dramatically increased. Bisulphite genomic sequencing and methylation-specific PCR detected promoter methylation, which was associated with decreased ADAMTS9 expression. Hypermethylation was also detected in 130/219 (59.4%) of primary tumours but only in 4.5% (2/44) of paired surgical margin tissues. Ectopic expression of ADAMTS9 in tumor cells induced significant growth suppression, cell cycle arrest at the G0/G1 phase, enhanced apoptosis and reduced cell migration and invasion. Conditioned culture medium from ADAMTS9-transfected BT549 cells markedly disrupted tube formation ability of human umbilical vein endothelial cell (HUVEC) in Matrigel. Furthermore, ADAMTS9 inhibited AKT signaling and its downstream targets (MDM2, p53, p21, p27, E-cadherin, VIM, SNAIL, VEGFA, NFκB-p65 and MMP2). In addition, we demonstrated, for the first time, that ADAMTS9 inhibits AKT signaling, through suppressing its upstream activators EGFR and TGFβ1/TβR(I/II) in breast cancer cells. Our results suggest that ADAMTS9 is a TSG epigenetically inactivated in breast cancer, which functions through blocking EGFR- and TGFβ1/TβR(I/II)-activated AKT signaling. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Id1 suppresses anti-tumour immune responses and promotes tumour progression by impairing myeloid cell maturation.

PubMed

Papaspyridonos, Marianna; Matei, Irina; Huang, Yujie; do Rosario Andre, Maria; Brazier-Mitouart, Helene; Waite, Janelle C; Chan, April S; Kalter, Julie; Ramos, Ilyssa; Wu, Qi; Williams, Caitlin; Wolchok, Jedd D; Chapman, Paul B; Peinado, Hector; Anandasabapathy, Niroshana; Ocean, Allyson J; Kaplan, Rosandra N; Greenfield, Jeffrey P; Bromberg, Jacqueline; Skokos, Dimitris; Lyden, David

2015-04-29

A central mechanism of tumour progression and metastasis involves the generation of an immunosuppressive 'macroenvironment' mediated in part through tumour-secreted factors. Here we demonstrate that upregulation of the Inhibitor of Differentiation 1 (Id1), in response to tumour-derived factors, such as TGFβ, is responsible for the switch from dendritic cell (DC) differentiation to myeloid-derived suppressor cell expansion during tumour progression. Genetic inactivation of Id1 largely corrects the myeloid imbalance, whereas Id1 overexpression in the absence of tumour-derived factors re-creates it. Id1 overexpression leads to systemic immunosuppression by downregulation of key molecules involved in DC differentiation and suppression of CD8 T-cell proliferation, thus promoting primary tumour growth and metastatic progression. Furthermore, advanced melanoma patients have increased plasma TGFβ levels and express higher levels of ID1 in myeloid peripheral blood cells. This study reveals a critical role for Id1 in suppressing the anti-tumour immune response during tumour progression and metastasis.

Mutation of von Hippel–Lindau Tumour Suppressor and Human Cardiopulmonary Physiology

PubMed Central

Smith, Thomas G; Brooks, Jerome T; Balanos, George M; Lappin, Terence R; Layton, D. Mark; Leedham, Dawn L; Liu, Chun; Maxwell, Patrick H; McMullin, Mary F; McNamara, Christopher J; Percy, Melanie J; Pugh, Christopher W; Ratcliffe, Peter J; Talbot, Nick P; Treacy, Marilyn; Robbins, Peter A

2006-01-01

Background The von Hippel–Lindau tumour suppressor protein–hypoxia-inducible factor (VHL–HIF) pathway has attracted widespread medical interest as a transcriptional system controlling cellular responses to hypoxia, yet insights into its role in systemic human physiology remain limited. Chuvash polycythaemia has recently been defined as a new form of VHL-associated disease, distinct from the classical VHL-associated inherited cancer syndrome, in which germline homozygosity for a hypomorphic VHL allele causes a generalised abnormality in VHL–HIF signalling. Affected individuals thus provide a unique opportunity to explore the integrative physiology of this signalling pathway. This study investigated patients with Chuvash polycythaemia in order to analyse the role of the VHL–HIF pathway in systemic human cardiopulmonary physiology. Methods and Findings Twelve participants, three with Chuvash polycythaemia and nine controls, were studied at baseline and during hypoxia. Participants breathed through a mouthpiece, and pulmonary ventilation was measured while pulmonary vascular tone was assessed echocardiographically. Individuals with Chuvash polycythaemia were found to have striking abnormalities in respiratory and pulmonary vascular regulation. Basal ventilation and pulmonary vascular tone were elevated, and ventilatory, pulmonary vasoconstrictive, and heart rate responses to acute hypoxia were greatly increased. Conclusions The features observed in this small group of patients with Chuvash polycythaemia are highly characteristic of those associated with acclimatisation to the hypoxia of high altitude. More generally, the phenotype associated with Chuvash polycythaemia demonstrates that VHL plays a major role in the underlying calibration and homeostasis of the respiratory and cardiovascular systems, most likely through its central role in the regulation of HIF. PMID:16768548

Testin (TES) as a candidate tumour suppressor and prognostic marker in human astrocytoma.

PubMed

Steponaitis, Giedrius; Kazlauskas, Arunas; Skiriute, Daina; Valiulyte, Indre; Skauminas, Kestutis; Tamasauskas, Arimantas; Vaitkiene, Paulina

2016-11-01

Astrocytomas are one of the most common brain tumours; however, the current methods used to characterize these tumours are inadequate. The establishment of molecular markers may identify variables required to improve tumour characterization and subtyping, and may aid to specify targets for improved treatment with essential prognostic value for patient survival. One such candidate is testin (TES), which was reported to have prognostic value for glioblastoma patients. However, the role of TES protein in gliomagenesis is currently unknown. In the present study, the methylation status of the TES promoter was investigated in post-operative astrocytoma tumours of different malignancy grade, and its association with the survival of astrocytoma patients was evaluated. In addition, the expression of TES protein was investigated in the same set of astrocytoma tumours tissue, and the association of protein expression with glioma patients survival was evaluated. The methylation status of TES was assessed by methylation-specific polymerase chain reaction in 138 different grade astrocytoma samples. Western blot analysis was used to characterize the expression pattern of TES in 86 different grade astrocytoma specimens: 13 of pathological grade I, 31 of pathological grade II, 17 of pathological grade III and 25 of pathological grade IV (glioblastoma). Statistical analyses were conducted to investigate the association between tumour molecular pattern, patient clinical variables and overall survival. The methylation analysis of the TES promoter exhibited a distinct profile between astrocytomas of different malignancy grade (P<0.001). Furthermore, gene promoter methylation was significantly associated with patients' age, survival and pathological grade (P<0.001). The protein expression level of TES was significantly lower in glioblastoma (grade IV astrocytoma) than in lower grade (II-III) astrocytoma tissue (P=0.028 and P=0.04, respectively). Additionally, short overall survival of

Testin (TES) as a candidate tumour suppressor and prognostic marker in human astrocytoma

PubMed Central

Steponaitis, Giedrius; Kazlauskas, Arunas; Skiriute, Daina; Valiulyte, Indre; Skauminas, Kestutis; Tamasauskas, Arimantas; Vaitkiene, Paulina

2016-01-01

Astrocytomas are one of the most common brain tumours; however, the current methods used to characterize these tumours are inadequate. The establishment of molecular markers may identify variables required to improve tumour characterization and subtyping, and may aid to specify targets for improved treatment with essential prognostic value for patient survival. One such candidate is testin (TES), which was reported to have prognostic value for glioblastoma patients. However, the role of TES protein in gliomagenesis is currently unknown. In the present study, the methylation status of the TES promoter was investigated in post-operative astrocytoma tumours of different malignancy grade, and its association with the survival of astrocytoma patients was evaluated. In addition, the expression of TES protein was investigated in the same set of astrocytoma tumours tissue, and the association of protein expression with glioma patients survival was evaluated. The methylation status of TES was assessed by methylation-specific polymerase chain reaction in 138 different grade astrocytoma samples. Western blot analysis was used to characterize the expression pattern of TES in 86 different grade astrocytoma specimens: 13 of pathological grade I, 31 of pathological grade II, 17 of pathological grade III and 25 of pathological grade IV (glioblastoma). Statistical analyses were conducted to investigate the association between tumour molecular pattern, patient clinical variables and overall survival. The methylation analysis of the TES promoter exhibited a distinct profile between astrocytomas of different malignancy grade (P<0.001). Furthermore, gene promoter methylation was significantly associated with patients' age, survival and pathological grade (P<0.001). The protein expression level of TES was significantly lower in glioblastoma (grade IV astrocytoma) than in lower grade (II–III) astrocytoma tissue (P=0.028 and P=0.04, respectively). Additionally, short overall survival of

Recurrent pregnancy failure is associated with a polymorphism in the p53 tumour suppressor gene.

PubMed

Pietrowski, Detlef; Bettendorf, Hertha; Riener, Eva-Katrin; Keck, Christoph; Hefler, Lukas A; Huber, Johannes C; Tempfer, Clemens

2005-04-01

The p53 tumour suppressor gene is a well-known factor regulating apoptosis in a wide variety of cells and tissues. Alterations in the p53 gene are among the most common genetic changes in human cancers. In addition, recent data provide evidence that p53 plays a critical role in mediating pregnancy by regulating steroid hormone activation. In idiopathic recurrent miscarriages (IRM), causes and associations are much debated as the exact pathophysiological mechanisms are unknown. In this study, we assess whether an established polymorphism in the p53 gene is associated with the occurrence of IRM. Genotyping was performed by PCR-based amplification of the p53 Arg and Pro variants at codon 72 in 175 cases of IRM and 143 controls. We observed a statistically significant association between carriage of the Pro allele and the occurrence of IRM (P = 0.03, odds ratio 1.49, confidence interval 1.04-2.14). Distribution of genotypes was in Hardy-Weinberg equilibrium. Our results indicate an over-representation of the Pro allele of the p53 gene in women with IRM, giving support to the theory that p53 has a potential role during pregnancy.

Tumor suppressor identified as inhibitor of inflammation

Cancer.gov

Scientists at NCI have found that a protein, FBXW7, which acts as a tumor suppressor, is also important for the reduction in strength of inflammatory pathways. It has long been recognized that a complex interaction exists between cancer causing mechanisms

The LKB1-AMPK pathway: metabolism and growth control in tumour suppression.

PubMed

Shackelford, David B; Shaw, Reuben J

2009-08-01

In the past decade, studies of the human tumour suppressor LKB1 have uncovered a novel signalling pathway that links cell metabolism to growth control and cell polarity. LKB1 encodes a serine-threonine kinase that directly phosphorylates and activates AMPK, a central metabolic sensor. AMPK regulates lipid, cholesterol and glucose metabolism in specialized metabolic tissues, such as liver, muscle and adipose tissue. This function has made AMPK a key therapeutic target in patients with diabetes. The connection of AMPK with several tumour suppressors suggests that therapeutic manipulation of this pathway using established diabetes drugs warrants further investigation in patients with cancer.

A genome-wide shRNA screen identifies GAS1 as a novel melanoma metastasis suppressor gene.

PubMed

Gobeil, Stephane; Zhu, Xiaochun; Doillon, Charles J; Green, Michael R

2008-11-01

Metastasis suppressor genes inhibit one or more steps required for metastasis without affecting primary tumor formation. Due to the complexity of the metastatic process, the development of experimental approaches for identifying genes involved in metastasis prevention has been challenging. Here we describe a genome-wide RNAi screening strategy to identify candidate metastasis suppressor genes. Following expression in weakly metastatic B16-F0 mouse melanoma cells, shRNAs were selected based upon enhanced satellite colony formation in a three-dimensional cell culture system and confirmed in a mouse experimental metastasis assay. Using this approach we discovered 22 genes whose knockdown increased metastasis without affecting primary tumor growth. We focused on one of these genes, Gas1 (Growth arrest-specific 1), because we found that it was substantially down-regulated in highly metastatic B16-F10 melanoma cells, which contributed to the high metastatic potential of this mouse cell line. We further demonstrated that Gas1 has all the expected properties of a melanoma tumor suppressor including: suppression of metastasis in a spontaneous metastasis assay, promotion of apoptosis following dissemination of cells to secondary sites, and frequent down-regulation in human melanoma metastasis-derived cell lines and metastatic tumor samples. Thus, we developed a genome-wide shRNA screening strategy that enables the discovery of new metastasis suppressor genes.

LATS2 tumour specific mutations and down-regulation of the gene in non-small cell carcinoma.

PubMed

Strazisar, Mojca; Mlakar, Vid; Glavac, Damjan

2009-06-01

LATS2 is a new member of the LATS tumour suppressor family. The human LATS2 gene is located at chromosome 13q11-12, a hot spot (67%) for loss of heterozygosity (LOH) in non-small cell lung cancer (NSCLC). We screened 129 non-small cell lung cancer samples and 13 lung cancer cell lines, initially for mutations in the LATS2 gene and subsequently for mutations in P53 and K-RAS genes. Either polymorphisms or mutations were identified in over 50 percent of analysed tumours. A novel missense mutation, S1073R, and a large deletion of 8 amino acids in the PAPA-repeat region were detected in 9 and 2 NSCLC tumours, respectively. Those mutations were not identified in the 13 lung cancer cell lines. Mutations were tumour specific and were absent from adjacent normal tissue and healthy controls. Down-regulation of the LATS2 gene was observed in most NSCLC tumours but was not related to any mutation or polymorphism. Tumours with a LATS2 mutation often also harbour a P53 but not K-RAS gene mutation and were mostly in an advanced stage of development, with regional lymph node involvement.

Why do viruses cause cancer? Highlights of the first century of human tumour virology

PubMed Central

Moore, Patrick S.; Chang, Yuan

2013-01-01

The year 2011 marks the centenary of Francis Peyton Rous’s landmark experiments on an avian cancer virus. Since then, seven human viruses have been found to cause 10–15% of human cancers worldwide. Viruses have been central to modern cancer research and provide profound insights into both infectious and non-infectious cancer causes. This diverse group of viruses reveals unexpected connections between innate immunity, immune sensors and tumour suppressor signalling that control both viral infection and cancer. This Timeline article describes common features of human tumour viruses and discusses how new technologies can be used to identify infectious causes of cancer. PMID:21102637

Tumour testing to identify Lynch syndrome in two Australian colorectal cancer cohorts

PubMed Central

Eriksen, Stine V.; Walsh, Michael D.; Walters, Rhiannon J.; Thibodeau, Stephen N.; Stewart, Jenna; Preston, Susan; Win, Aung Ko; Flander, Louisa; Ouakrim, Driss Ait; Macrae, Finlay A.; Boussioutas, Alex; Winship, Ingrid M.; Giles, Graham G.; Hopper, John L.; Southey, Melissa C.

2016-01-01

Background and Aim Tumour testing of colorectal cancers (CRC) for mismatch repair (MMR) deficiency is an effective approach to identify carriers of germline MMR gene mutation (Lynch syndrome). The aim of this study was to identify MMR gene mutation carriers in two cohorts of population-based CRC utilising a combination of tumour and germline testing approaches. Methods CRCs from 813 patients diagnosed with CRC <60 years of age from the Australasian Colorectal Cancer Family Registry (ACCFR) and from 826 patients from the Melbourne Collaborative Cohort Study (MCCS) were tested for MMR protein expression using immunohistochemistry (IHC), microsatellite instability (MSI), BRAFV600E somatic mutation and for MLH1 methylation. MMR gene mutation testing (Sanger sequencing and MLPA) was performed on germline DNA of patients with MMR-deficient tumours and a subset of MMR-proficient CRCs. Results Of the 813 ACCFR probands, 90 probands demonstrated tumour MMR-deficiency (11.1%) and 42 had a MMR gene germline mutation (5.2%). For the MCCS, MMR-deficiency was identified in the tumours of 103 probands (12.5%) and 7 had a germline mutation (0.8%). All the mutation carriers were diagnosed prior to 70 years of age. Probands with a MMR-deficient CRC without MLH1 methylation and a gene mutation were considered Lynch-like and comprised 41.1% and 22.3% of the MMR-deficient CRCs for the ACCFR and MCCS, respectively. Conclusions Identification of MMR gene mutation carriers in Australian CRC-affected patients is optimised by IHC screening of CRC diagnosed before 70 years. A significant proportion of MMR-deficient CRCs will have unknown aetiology (Lynch-like) proving problematic for clinical management. PMID:27273229

Reverse engineering of TLX oncogenic transcriptional networks identifies RUNX1 as tumor suppressor in T-ALL.

PubMed

Della Gatta, Giusy; Palomero, Teresa; Perez-Garcia, Arianne; Ambesi-Impiombato, Alberto; Bansal, Mukesh; Carpenter, Zachary W; De Keersmaecker, Kim; Sole, Xavier; Xu, Luyao; Paietta, Elisabeth; Racevskis, Janis; Wiernik, Peter H; Rowe, Jacob M; Meijerink, Jules P; Califano, Andrea; Ferrando, Adolfo A

2012-02-26

The TLX1 and TLX3 transcription factor oncogenes have a key role in the pathogenesis of T cell acute lymphoblastic leukemia (T-ALL). Here we used reverse engineering of global transcriptional networks to decipher the oncogenic regulatory circuit controlled by TLX1 and TLX3. This systems biology analysis defined T cell leukemia homeobox 1 (TLX1) and TLX3 as master regulators of an oncogenic transcriptional circuit governing T-ALL. Notably, a network structure analysis of this hierarchical network identified RUNX1 as a key mediator of the T-ALL induced by TLX1 and TLX3 and predicted a tumor-suppressor role for RUNX1 in T cell transformation. Consistent with these results, we identified recurrent somatic loss-of-function mutations in RUNX1 in human T-ALL. Overall, these results place TLX1 and TLX3 at the top of an oncogenic transcriptional network controlling leukemia development, show the power of network analyses to identify key elements in the regulatory circuits governing human cancer and identify RUNX1 as a tumor-suppressor gene in T-ALL.

Checkpoint Blockade Cancer Immunotherapy Targets Tumour-Specific Mutant Antigens

PubMed Central

Gubin, Matthew M.; Zhang, Xiuli; Schuster, Heiko; Caron, Etienne; Ward, Jeffrey P.; Noguchi, Takuro; Ivanova, Yulia; Hundal, Jasreet; Arthur, Cora D.; Krebber, Willem-Jan; Mulder, Gwenn E.; Toebes, Mireille; Vesely, Matthew D.; Lam, Samuel S.K.; Korman, Alan J.; Allison, James P.; Freeman, Gordon J.; Sharpe, Arlene H.; Pearce, Erika L.; Schumacher, Ton N.; Aebersold, Ruedi; Rammensee, Hans-Georg; Melief, Cornelis J. M.; Mardis, Elaine R.; Gillanders, William E.; Artyomov, Maxim N.; Schreiber, Robert D.

2014-01-01

The immune system plays key roles in determining the fate of developing cancers by not only functioning as a tumour promoter facilitating cellular transformation, promoting tumour growth and sculpting tumour cell immunogenicity1–6, but also as an extrinsic tumour suppressor that either destroys developing tumours or restrains their expansion1,2,7. Yet clinically apparent cancers still arise in immunocompetent individuals in part as a consequence of cancer induced immunosuppression. In many individuals, immunosuppression is mediated by Cytotoxic T-Lymphocyte Associated Antigen-4 (CTLA-4) and Programmed Death-1 (PD-1), two immunomodulatory receptors expressed on T cells8,9. Monoclonal antibody (mAb) based therapies targeting CTLA-4 and/or PD-1 (checkpoint blockade) have yielded significant clinical benefits—including durable responses—to patients with different malignancies10–13. However, little is known about the identity of the tumour antigens that function as the targets of T cells activated by checkpoint blockade immunotherapy and whether these antigens can be used to generate vaccines that are highly tumour-specific. Herein, we use genomics and bioinformatics approaches to identify tumour-specific mutant proteins as a major class of T cell rejection antigens following αPD-1 and/or αCTLA-4 therapy of mice bearing progressively growing sarcomas and show that therapeutic synthetic long peptide (SLP) vaccines incorporating these mutant epitopes induce tumour rejection comparably to checkpoint blockade immunotherapy. Whereas, mutant tumour antigen-specific T cells are present in progressively growing tumours, they are reactivated following treatment with αPD-1- and/or αCTLA-4 and display some overlapping but mostly treatment-specific transcriptional profiles rendering them capable of mediating tumour rejection. These results reveal that tumour-specific mutant antigens (TSMA) are not only important targets of checkpoint blockade therapy but also can be

Lethal Giant Larvae 1 Tumour Suppressor Activity Is Not Conserved in Models of Mammalian T and B Cell Leukaemia

PubMed Central

Hawkins, Edwin D.; Oliaro, Jane; Ramsbottom, Kelly M.; Ting, Stephen B.; Sacirbegovic, Faruk; Harvey, Michael; Kinwell, Tanja; Ghysdael, Jacques; Johnstone, Ricky W.; Humbert, Patrick O.; Russell, Sarah M.

2014-01-01

In epithelial and stem cells, lethal giant larvae (Lgl) is a potent tumour suppressor, a regulator of Notch signalling, and a mediator of cell fate via asymmetric cell division. Recent evidence suggests that the function of Lgl is conserved in mammalian haematopoietic stem cells and implies a contribution to haematological malignancies. To date, direct measurement of the effect of Lgl expression on malignancies of the haematopoietic lineage has not been tested. In Lgl1−/− mice, we analysed the development of haematopoietic malignancies either alone, or in the presence of common oncogenic lesions. We show that in the absence of Lgl1, production of mature white blood cell lineages and long-term survival of mice are not affected. Additionally, loss of Lgl1 does not alter leukaemia driven by constitutive Notch, c-Myc or Jak2 signalling. These results suggest that the role of Lgl1 in the haematopoietic lineage might be restricted to specific co-operating mutations and a limited number of cellular contexts. PMID:24475281

TIMP3 Promoter Methylation Represents an Epigenetic Marker of BRCA1ness Breast Cancer Tumours.

PubMed

Maleva Kostovska, Ivana; Jakimovska, Milena; Popovska-Jankovic, Katerina; Kubelka-Sabit, Katerina; Karagjozov, Mitko; Plaseska-Karanfilska, Dijana

2018-03-09

Tumours presenting BRCAness profile behave more aggressively and are more invasive as a consequence of their complex genetic and epigenetic alterations, caused by impaired fidelity of the DNA repair processes. Methylation of promoter CpG islands represents an alternative mechanism to inactivate DNA repair and tumour suppressor genes. In our study, we analyzed the frequency of methylation changes of 24 tumour suppressor genes and explored their association with BRCAness profile. BRCA1ness profile and aberrant methylation were studied in 233 fresh frozen breast tumour tissues by Multiplex Ligation-dependent Probe Amplification (MLPA) and Methylation Specific (MS)-MLPA methods, respectively. Our analyses revealed that 12.4% of the breast cancer (BC) patients had tumours with a BRCA1ness profile. TIMP3 showed significantly higher (p = 5.8х10 -5 ) methylation frequency in tumours with BRCA1ness, while methylation of APC, GSTP1 and RASSF1 promoters was negatively associated with BRCA1ness (р = 0.0017, р = 0.007 and р = 0.046, respectively). TIMP3 methylation was also associated with triple negative (TN) BC. Furthermore, TN tumours showing BRCA1ness showed stronger association with TIMP3 methylation (p = 0.0008) in comparison to TN tumours without BRCA1ness (p = 0.009). In conclusion, we confirmed that TIMP3 methylation is a marker for TN tumours and furthermore we showed for the first time that TIMP3 promoter methylation is an epigenetic marker of BRCA1ness tumours.

Identifying Breast Tumor Suppressors Using in Vitro and in Vivo RNAi Screens

DTIC Science & Technology

2011-10-01

vivo RNA interference screen, breast cancer , tumor suppressor, leukemia inhibitory factor receptor (LIFR) 16. SECURITY CLASSIFICATION OF: 17...The identification of these genes will improve the understanding of the causes of breast cancer , which may lead to therapeutic advancements for... breast cancer prevention and treatment. BODY Objective 1: Identification of breast tumor suppressors using in vitro and in vivo RNAi screens

The rise of testicular germ cell tumours: the search for causes, risk factors and novel therapeutic targets

PubMed Central

McLaughlin, Eileen A

2013-01-01

Since the beginning of the 20th century there has been a decline in the reproductive vitality of men within the Western world. The declining sperm quantity and quality has been associated with increased overt disorders of sexual development including hypospadias, undescended testes and type II testicular germ cell tumours (TGCTs). The increase in TGCTs cannot be accounted for by genetic changes in the population. Therefore exposure to environmental toxicants appears to be a major contributor to the aetiology of TGCTs and men with a genetic predisposition are particularly vulnerable. In particular, Type II TGCTs have been identified to arise from a precursor lesion Carcinoma in situ (CIS), identified as a dysfunctional gonocyte; however, the exact triggers for CIS development are currently unknown. Therefore the transition from gonocytes into spermatogonia is key to those studying TGCTs. Recently we have identified seven miRNA molecules (including members of the miR-290 family and miR-136, 463* and 743a) to be significantly changed over this transition period. These miRNA molecules are predicted to have targets within the CXCR4, PTEN, DHH, RAC and PDGF pathways, all of which have important roles in germ cell migration, proliferation and homing to the spermatogonial stem cell niche. Given the plethora of potential targets affected by each miRNA molecule, subtle changes in miRNA expression could have significant consequences e.g. tumourigenesis. The role of non-traditional oncogenes and tumour suppressors such as miRNA in TGCT is highlighted by the fact that the majority of these tumours express wild type p53, a pivotal tumour suppressor usually inactivated in cancer. While treatment of TGCTs is highly successful, the impact of these treatments on fertility means that identification of exact triggers, earlier diagnosis and alternate treatments are essential. This review examines the genetic factors and possible triggers of type II TGCT to highlight target areas for

T helper type 17 cells contribute to anti-tumour immunity and promote the recruitment of T helper type 1 cells to the tumour.

PubMed

Nuñez, Sarah; Saez, Juan Jose; Fernandez, Dominique; Flores-Santibañez, Felipe; Alvarez, Karla; Tejon, Gabriela; Ruiz, Paulina; Maldonado, Paula; Hidalgo, Yessia; Manriquez, Valeria; Bono, Maria Rosa; Rosemblatt, Mario; Sauma, Daniela

2013-05-01

T helper type 17 (Th17) lymphocytes are found in high frequency in tumour-burdened animals and cancer patients. These lymphocytes, characterized by the production of interleukin-17 and other pro-inflammatory cytokines, have a well-defined role in the development of inflammatory and autoimmune pathologies; however, their function in tumour immunity is less clear. We explored possible opposing anti-tumour and tumour-promoting functions of Th17 cells by evaluating tumour growth and the ability to promote tumour infiltration of myeloid-derived suppressor cells (MDSC), regulatory T cells and CD4(+)  interferon-γ(+) cells in a retinoic acid-like orphan receptor γt (RORγt) -deficient mouse model. A reduced percentage of Th17 cells in the tumour microenvironment in RORγt-deficient mice led to enhanced tumour growth, that could be reverted by adoptive transfer of Th17 cells. Differences in tumour growth were not associated with changes in the accumulation or suppressive function of MDSC and regulatory T cells but were related to a decrease in the proportion of CD4(+) T cells in the tumour. Our results suggest that Th17 cells do not affect the recruitment of immunosuppressive populations but favour the recruitment of effector Th1 cells to the tumour, thereby promoting anti-tumour responses. © 2012 Blackwell Publishing Ltd.

p53 suppresses type II endometrial carcinomas in mice and governs endometrial tumour aggressiveness in humans

PubMed Central

Wild, Peter J; Ikenberg, Kristian; Fuchs, Thomas J; Rechsteiner, Markus; Georgiev, Strahil; Fankhauser, Niklaus; Noske, Aurelia; Roessle, Matthias; Caduff, Rosmarie; Dellas, Athanassios; Fink, Daniel; Moch, Holger; Krek, Wilhelm; Frew, Ian J

2012-01-01

Type II endometrial carcinomas are a highly aggressive group of tumour subtypes that are frequently associated with inactivation of the TP53 tumour suppressor gene. We show that mice with endometrium-specific deletion of Trp53 initially exhibited histological changes that are identical to known precursor lesions of type II endometrial carcinomas in humans and later developed carcinomas representing all type II subtypes. The mTORC1 signalling pathway was frequently activated in these precursor lesions and tumours, suggesting a genetic cooperation between this pathway and Trp53 deficiency in tumour initiation. Consistent with this idea, analyses of 521 human endometrial carcinomas identified frequent mTORC1 pathway activation in type I as well as type II endometrial carcinoma subtypes. mTORC1 pathway activation and p53 expression or mutation status each independently predicted poor patient survival. We suggest that molecular alterations in p53 and the mTORC1 pathway play different roles in the initiation of the different endometrial cancer subtypes, but that combined p53 inactivation and mTORC1 pathway activation are unifying pathogenic features among histologically diverse subtypes of late stage aggressive endometrial tumours. PMID:22678923

The mechanical microenvironment in cancer: How physics affects tumours.

PubMed

Nagelkerke, Anika; Bussink, Johan; Rowan, Alan E; Span, Paul N

2015-12-01

The tumour microenvironment contributes greatly to the response of tumour cells. It consists of chemical gradients, for example of oxygen and nutrients. However, a physical environment is also present. Apart from chemical input, cells also receive physical signals. Tumours display unique mechanical properties: they are a lot stiffer than normal tissue. This may be either a cause or a consequence of cancer, but literature suggests it has a major impact on tumour cells as will be described in this review. The mechanical microenvironment may cause malignant transformation, possibly through activation of oncogenic pathways and inhibition of tumour suppressor genes. In addition, the mechanical microenvironment may promote tumour progression by influencing processes such as epithelial-to-mesenchymal transition, enhancing cell survival through autophagy, but also affects sensitivity of tumour cells to therapeutics. Furthermore, multiple intracellular signalling pathways prove sensitive to the mechanical properties of the microenvironment. It appears the increased stiffness is unlikely to be caused by increased stiffness of the tumour cells themselves. However, there are indications that tumours display a higher cell density, making them more rigid. In addition, increased matrix deposition in the tumour, as well as increased interstitial fluid pressure may account for the increased stiffness of tumours. Overall, tumour mechanics are significantly different from normal tissue. Therefore, this feature should be further explored for use in cancer prevention, detection and treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Immunohistochemical expression of p53 proteins in Wilms' tumour: a possible association with the histological prognostic parameter of anaplasia.

PubMed

Cheah, P L; Looi, L M; Chan, L L

1996-01-01

Wilms' tumour (nephroblastoma) has been associated with chromosomal abnormalities at the 11p13, 11p15 and 16q regions. A study into the possibility of mutations occurring within p53, the ubiquitous adult tumour suppressor gene, in Wilms' tumour was carried out. Thirty-eight cases were studied. Of these 36 were categorised into the favourable histology group and two into the unfavourable histology group based on the National Wilms' Tumour Study criteria. Archival formalin-fixed, paraffin-embedded tissue sections from each case were stained with a polyclonal (AB565:Chemicon) and a monoclonal (DO7:Dako) antibody raised against p53 protein using a peroxidase-labelled streptavidin biotin kit (Dako). 'Cure' (disease-free survival of 60 months or longer) was documented in 39% of cases with favourable histology tumours. Eleven percent in this group succumbed to the disease. Both cases with unfavourable histology died. Four out of 36 (11%) tumours with favourable histology demonstrated weak to moderate staining with both AB565 and DO7 in more than 75% of tumour cells. In contrast, p53 protein expression in unfavourable histology tumours was significantly increased compared with the favourable histology group (P = 0.021) with both cases demonstrating immunopositivity in > 75% of tumour cells when stained with AB565 and DO7. The intensity of staining ranged from moderate to strong in both cases. It appears from this preliminary study that the immunohistochemical expression of p53 protein in Wilms' tumour, presumably a result of mutation in the p53 tumour suppressor gene, correlates with histological classification, histological categorisation being one of the useful features in the prognostic assessment of Wilms' tumours.

Platelet-activating factor receptor (PAF-R)-dependent pathways control tumour growth and tumour response to chemotherapy

PubMed Central

2010-01-01

Background Phagocytosis of apoptotic cells by macrophages induces a suppressor phenotype. Previous data from our group suggested that this occurs via Platelet-activating factor receptor (PAF-R)-mediated pathways. In the present study, we investigated the impact of apoptotic cell inoculation or induction by a chemotherapeutic agent (dacarbazine, DTIC) on tumour growth, microenvironmental parameters and survival, and the effect of treatment with a PAF-R antagonist (WEB2170). These studies were performed in murine tumours: Ehrlich Ascitis Tumour (EAT) and B16F10 melanoma. Methods Tumour growth was assessed by direct counting of EAT cells in the ascitis or by measuring the volume of the solid tumour. Parameters of the tumour microenvironment, such as the frequency of cells expressing cyclo-oxygenase-2 (COX-2), caspase-3 and galectin-3, and microvascular density, were determined by immunohistochemistry. Levels of vascular endothelium growth factor (VEGF) and prostaglandin E2 (PGE2) were determined by ELISA, and levels of nitric oxide (NO) by Griess reaction. PAF-R expression was analysed by immunohistochemistry and flow cytometry. Results Inoculation of apoptotic cells before EAT implantation stimulated tumour growth. This effect was reversed by in vivo pre-treatment with WEB2170. This treatment also reduced tumour growth and modified the microenvironment by reducing PGE2, VEGF and NO production. In B16F10 melanoma, WEB2170 alone or in association with DTIC significantly reduced tumour volume. Survival of the tumour-bearing mice was not affected by WEB2170 treatment but was significantly improved by the combination of DTIC with WEB2170. Tumour microenvironment elements were among the targets of the combination therapy since the relative frequency of COX-2 and galectin-3 positive cells and the microvascular density within the tumour mass were significantly reduced by treatment with WEB2170 or DTIC alone or in combination. Antibodies to PAF-R stained the cells from inside

Multiple endocrine neoplasia type 1 knockout mice develop parathyroid, pancreatic, pituitary and adrenal tumours with hypercalcaemia, hypophosphataemia and hypercorticosteronaemia.

PubMed

Harding, Brian; Lemos, Manuel C; Reed, Anita A C; Walls, Gerard V; Jeyabalan, Jeshmi; Bowl, Michael R; Tateossian, Hilda; Sullivan, Nicky; Hough, Tertius; Fraser, William D; Ansorge, Olaf; Cheeseman, Michael T; Thakker, Rajesh V

2009-12-01

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized in man by parathyroid, pancreatic, pituitary and adrenal tumours. The MEN1 gene encodes a 610-amino acid protein (menin) which is a tumour suppressor. To investigate the in vivo role of menin, we developed a mouse model, by deleting Men1 exons 1 and 2 and investigated this for MEN1-associated tumours and serum abnormalities. Men1(+/-) mice were viable and fertile, and 220 Men1(+/-) and 94 Men1(+/+) mice were studied between the ages of 3 and 21 months. Survival in Men1(+/-) mice was significantly lower than in Men1(+/+) mice (<68% vs >85%, P<0.01). Men1(+/-) mice developed, by 9 months of age, parathyroid hyperplasia, pancreatic tumours which were mostly insulinomas, by 12 months of age, pituitary tumours which were mostly prolactinomas, and by 15 months parathyroid adenomas and adrenal cortical tumours. Loss of heterozygosity and menin expression was demonstrated in the tumours, consistent with a tumour suppressor role for the Men1 gene. Men1(+/-) mice with parathyroid neoplasms were hypercalcaemic and hypophosphataemic, with inappropriately normal serum parathyroid hormone concentrations. Pancreatic and pituitary tumours expressed chromogranin A (CgA), somatostatin receptor type 2 and vascular endothelial growth factor-A. Serum CgA concentrations in Men1(+/-) mice were not elevated. Adrenocortical tumours, which immunostained for 3-beta-hydroxysteroid dehydrogenase, developed in seven Men1(+/-) mice, but resulted in hypercorticosteronaemia in one out of the four mice that were investigated. Thus, these Men1(+/-) mice are representative of MEN1 in man, and will help in investigating molecular mechanisms and treatments for endocrine tumours.

Novel somatic and germline mutations in intracranial germ cell tumours.

PubMed

Wang, Linghua; Yamaguchi, Shigeru; Burstein, Matthew D; Terashima, Keita; Chang, Kyle; Ng, Ho-Keung; Nakamura, Hideo; He, Zongxiao; Doddapaneni, Harshavardhan; Lewis, Lora; Wang, Mark; Suzuki, Tomonari; Nishikawa, Ryo; Natsume, Atsushi; Terasaka, Shunsuke; Dauser, Robert; Whitehead, William; Adekunle, Adesina; Sun, Jiayi; Qiao, Yi; Marth, Gábor; Muzny, Donna M; Gibbs, Richard A; Leal, Suzanne M; Wheeler, David A; Lau, Ching C

2014-07-10

Intracranial germ cell tumours (IGCTs) are a group of rare heterogeneous brain tumours that are clinically and histologically similar to the more common gonadal GCTs. IGCTs show great variation in their geographical and gender distribution, histological composition and treatment outcomes. The incidence of IGCTs is historically five- to eightfold greater in Japan and other East Asian countries than in Western countries, with peak incidence near the time of puberty. About half of the tumours are located in the pineal region. The male-to-female incidence ratio is approximately 3-4:1 overall, but is even higher for tumours located in the pineal region. Owing to the scarcity of tumour specimens available for research, little is currently known about this rare disease. Here we report the analysis of 62 cases by next-generation sequencing, single nucleotide polymorphism array and expression array. We find the KIT/RAS signalling pathway frequently mutated in more than 50% of IGCTs, including novel recurrent somatic mutations in KIT, its downstream mediators KRAS and NRAS, and its negative regulator CBL. Novel somatic alterations in the AKT/mTOR pathway included copy number gains of the AKT1 locus at 14q32.33 in 19% of patients, with corresponding upregulation of AKT1 expression. We identified loss-of-function mutations in BCORL1, a transcriptional co-repressor and tumour suppressor. We report significant enrichment of novel and rare germline variants in JMJD1C, which codes for a histone demethylase and is a coactivator of the androgen receptor, among Japanese IGCT patients. This study establishes a molecular foundation for understanding the biology of IGCTs and suggests potentially promising therapeutic strategies focusing on the inhibition of KIT/RAS activation and the AKT1/mTOR pathway.

Tumor suppressors: enhancers or suppressors of regeneration?

PubMed Central

Pomerantz, Jason H.; Blau, Helen M.

2013-01-01

Tumor suppressors are so named because cancers occur in their absence, but these genes also have important functions in development, metabolism and tissue homeostasis. Here, we discuss known and potential functions of tumor suppressor genes during tissue regeneration, focusing on the evolutionarily conserved tumor suppressors pRb1, p53, Pten and Hippo. We propose that their activity is essential for tissue regeneration. This is in contrast to suggestions that tumor suppression is a trade-off for regenerative capacity. We also hypothesize that certain aspects of tumor suppressor pathways inhibit regenerative processes in mammals, and that transient targeted modification of these pathways could be fruitfully exploited to enhance processes that are important to regenerative medicine. PMID:23715544

Tumour angiogenesis is reduced in the Tc1 mouse model of Down's syndrome.

PubMed

Reynolds, Louise E; Watson, Alan R; Baker, Marianne; Jones, Tania A; D'Amico, Gabriela; Robinson, Stephen D; Joffre, Carine; Garrido-Urbani, Sarah; Rodriguez-Manzaneque, Juan Carlos; Martino-Echarri, Estefanía; Aurrand-Lions, Michel; Sheer, Denise; Dagna-Bricarelli, Franca; Nizetic, Dean; McCabe, Christopher J; Turnell, Andrew S; Kermorgant, Stephanie; Imhof, Beat A; Adams, Ralf; Fisher, Elizabeth M C; Tybulewicz, Victor L J; Hart, Ian R; Hodivala-Dilke, Kairbaan M

2010-06-10

Down's syndrome (DS) is a genetic disorder caused by full or partial trisomy of human chromosome 21 and presents with many clinical phenotypes including a reduced incidence of solid tumours. Recent work with the Ts65Dn model of DS, which has orthologues of about 50% of the genes on chromosome 21 (Hsa21), has indicated that three copies of the ETS2 (ref. 3) or DS candidate region 1 (DSCR1) genes (a previously known suppressor of angiogenesis) is sufficient to inhibit tumour growth. Here we use the Tc1 transchromosomic mouse model of DS to dissect the contribution of extra copies of genes on Hsa21 to tumour angiogenesis. This mouse expresses roughly 81% of Hsa21 genes but not the human DSCR1 region. We transplanted B16F0 and Lewis lung carcinoma tumour cells into Tc1 mice and showed that growth of these tumours was substantially reduced compared with wild-type littermate controls. Furthermore, tumour angiogenesis was significantly repressed in Tc1 mice. In particular, in vitro and in vivo angiogenic responses to vascular endothelial growth factor (VEGF) were inhibited. Examination of the genes on the segment of Hsa21 in Tc1 mice identified putative anti-angiogenic genes (ADAMTS1and ERG) and novel endothelial cell-specific genes, never previously shown to be involved in angiogenesis (JAM-B and PTTG1IP), that, when overexpressed, are responsible for inhibiting angiogenic responses to VEGF. Three copies of these genes within the stromal compartment reduced tumour angiogenesis, explaining the reduced tumour growth in DS. Furthermore, we expect that, in addition to the candidate genes that we show to be involved in the repression of angiogenesis, the Tc1 mouse model of DS will permit the identification of other endothelium-specific anti-angiogenic targets relevant to a broad spectrum of cancer patients.

NFκB1 is a suppressor of neutrophil-driven hepatocellular carcinoma

NASA Astrophysics Data System (ADS)

Wilson, C. L.; Jurk, D.; Fullard, N.; Banks, P.; Page, A.; Luli, S.; Elsharkawy, A. M.; Gieling, R. G.; Chakraborty, J. Bagchi; Fox, C.; Richardson, C.; Callaghan, K.; Blair, G. E.; Fox, N.; Lagnado, A.; Passos, J. F.; Moore, A. J.; Smith, G. R.; Tiniakos, D. G.; Mann, J.; Oakley, F.; Mann, D. A.

2015-04-01

Hepatocellular carcinoma (HCC) develops on the background of chronic hepatitis. Leukocytes found within the HCC microenvironment are implicated as regulators of tumour growth. We show that diethylnitrosamine (DEN)-induced murine HCC is attenuated by antibody-mediated depletion of hepatic neutrophils, the latter stimulating hepatocellular ROS and telomere DNA damage. We additionally report a previously unappreciated tumour suppressor function for hepatocellular nfkb1 operating via p50:p50 dimers and the co-repressor HDAC1. These anti-inflammatory proteins combine to transcriptionally repress hepatic expression of a S100A8/9, CXCL1 and CXCL2 neutrophil chemokine network. Loss of nfkb1 promotes ageing-associated chronic liver disease (CLD), characterized by steatosis, neutrophillia, fibrosis, hepatocyte telomere damage and HCC. Nfkb1S340A/S340Amice carrying a mutation designed to selectively disrupt p50:p50:HDAC1 complexes are more susceptible to HCC; by contrast, mice lacking S100A9 express reduced neutrophil chemokines and are protected from HCC. Inhibiting neutrophil accumulation in CLD or targeting their tumour-promoting activities may offer therapeutic opportunities in HCC.

MicroRNA drop in the bloodstream and microRNA boost in the tumour caused by treatment with ribonuclease A leads to an attenuation of tumour malignancy.

PubMed

Mironova, Nadezhda; Patutina, Olga; Brenner, Evgenyi; Kurilshikov, Alexander; Vlassov, Valentin; Zenkova, Marina

2013-01-01

Novel data showing an important role of microRNAs in mediating tumour progression opened a new field of possible molecular targets for cytotoxic ribonucleases. Recently, antitumour and antimetastatic activities of pancreatic ribonuclease A were demonstrated and here genome-wide profiles of microRNAs in the tumour and blood of mice bearing Lewis lung carcinoma after treatment with RNase A were analysed by high-throughput Sequencing by Oligonucleotide Ligation and Detection (SOLiD™) sequencing technology. Sequencing data showed that RNase A therapy resulted in the boost of 116 microRNAs in tumour tissue and a significant drop of 137 microRNAs in the bloodstream that were confirmed by qPCR. The microRNA boost in the tumour was accompanied by the overexpression of microRNA processing genes: RNASEN (Drosha), xpo5, dicer1, and eif2c2 (Ago2). Ribonuclease activity of RNase A was shown to be crucial for the activation of both microRNA synthesis and expression of the microRNA processing genes. In the tumour tissue, RNase A caused the upregulation of both oncomirs and tumour-suppressor microRNAs, including microRNAs of the let-7 family, known to negatively regulate tumour progression. Our results suggest that the alteration of microRNA signature caused by RNase A treatment leads to the attenuation of tumour malignancy.

Tumour-derived PGD2 and NKp30-B7H6 engagement drives an immunosuppressive ILC2-MDSC axis.

PubMed

Trabanelli, Sara; Chevalier, Mathieu F; Martinez-Usatorre, Amaia; Gomez-Cadena, Alejandra; Salomé, Bérengère; Lecciso, Mariangela; Salvestrini, Valentina; Verdeil, Grégory; Racle, Julien; Papayannidis, Cristina; Morita, Hideaki; Pizzitola, Irene; Grandclément, Camille; Bohner, Perrine; Bruni, Elena; Girotra, Mukul; Pallavi, Rani; Falvo, Paolo; Leibundgut, Elisabeth Oppliger; Baerlocher, Gabriela M; Carlo-Stella, Carmelo; Taurino, Daniela; Santoro, Armando; Spinelli, Orietta; Rambaldi, Alessandro; Giarin, Emanuela; Basso, Giuseppe; Tresoldi, Cristina; Ciceri, Fabio; Gfeller, David; Akdis, Cezmi A; Mazzarella, Luca; Minucci, Saverio; Pelicci, Pier Giuseppe; Marcenaro, Emanuela; McKenzie, Andrew N J; Vanhecke, Dominique; Coukos, George; Mavilio, Domenico; Curti, Antonio; Derré, Laurent; Jandus, Camilla

2017-09-19

Group 2 innate lymphoid cells (ILC2s) are involved in human diseases, such as allergy, atopic dermatitis and nasal polyposis, but their function in human cancer remains unclear. Here we show that, in acute promyelocytic leukaemia (APL), ILC2s are increased and hyper-activated through the interaction of CRTH2 and NKp30 with elevated tumour-derived PGD2 and B7H6, respectively. ILC2s, in turn, activate monocytic myeloid-derived suppressor cells (M-MDSCs) via IL-13 secretion. Upon treating APL with all-trans retinoic acid and achieving complete remission, the levels of PGD2, NKp30, ILC2s, IL-13 and M-MDSCs are restored. Similarly, disruption of this tumour immunosuppressive axis by specifically blocking PGD2, IL-13 and NKp30 partially restores ILC2 and M-MDSC levels and results in increased survival. Thus, using APL as a model, we uncover a tolerogenic pathway that may represent a relevant immunosuppressive, therapeutic targetable, mechanism operating in various human tumour types, as supported by our observations in prostate cancer.Group 2 innate lymphoid cells (ILC2s) modulate inflammatory and allergic responses, but their function in cancer immunity is still unclear. Here the authors show that, in acute promyelocytic leukaemia, tumour-activated ILC2s secrete IL-13 to induce myeloid-derived suppressor cells and support tumour growth.

Molecular markers in dysplasia of the larynx: expression of cyclin-dependent kinase inhibitors p21, p27 and p53 tumour suppressor gene in predicting cancer risk.

PubMed

Jeannon, J-P; Soames, J V; Aston, V; Stafford, F W; Wilson, J A

2004-12-01

Premalignant conditions affect the larynx. Dysplasia can progress in severity resulting in cancer depending on many clinical, pathological and molecular factors. The purpose of this study was to examine the expression of the p21 and p27 cyclin-dependent kinase inhibitors and p53 tumour suppressor gene in dysplasia of the larynx. A total of 114 cases of untreated dysplasia were selected from the archives of the University of Newcastle. p21, p27 and p53 immunohistochemistry was performed and the cases followed up. Twenty-eight dysplasias (24%) subsequently developed into cancers. Expression of the molecular factors studied was not associated with cancer progression. p53 expression was associated with smoking (P = 0.005). In contrast, grade of dysplasia was significantly associated with cancer risk (odds ratio 6.7; P = 0.0001). The majority (75%) of cancers were detected within 12 months of dysplasia being diagnosed.

Tumour specific promoter region methylation of the human homologue of the Drosophila Roundabout gene DUTT1 (ROBO1) in human cancers.

PubMed

Dallol, Ashraf; Forgacs, Eva; Martinez, Alonso; Sekido, Yoshitaka; Walker, Rosemary; Kishida, Takeshi; Rabbitts, Pamela; Maher, Eamonn R; Minna, John D; Latif, Farida

2002-05-02

The human homologue of the Drosophila Roundabout gene DUTT1 (Deleted in U Twenty Twenty) or ROBO1 (Locus Link ID 6091), a member of the NCAM family of receptors, was recently cloned from the lung cancer tumour suppressor gene region 2 (LCTSGR2 or U2020 region) at 3p12. DUTT1 maps within a region of overlapping homozygous deletions characterized in both small cell lung cancer lines (SCLC) and in a breast cancer line. In this report we (a) defined the genomic organization of the DUTT1 gene, (b) performed mutation and expression analysis of DUTT1 in lung, breast and kidney cancers, (c) identified tumour specific promoter region methylation of DUTT1 in human cancers. The gene was found to contain 29 exons and spans at least 240 kb of genomic sequence. The 5' region contains a CpG island, and the poly(A)(+) tail has an atypical 5'-GATAAA-3' signal. We analysed DUTT1 for mutations in lung, breast and kidney cancers, no inactivating mutations were detected by PCR-SSCP. However, seven germline missense changes were found and characterized. DUTT1 expression was not detectable in one out of 18 breast tumour lines analysed by RT-PCR. Bisulfite sequencing of the promoter region of DUTT1 gene in the HTB-19 breast tumour cell line (not expressing DUTT1) showed complete hypermethylation of CpG sites within the promoter region of the DUTT1 gene (-244 to +27 relative to the translation start site). The expression of DUTT1 gene was reactivated in HTB-19 after treatment with the demethylating agent 5-aza-2'-deoxycytidine. The same region was also found to be hypermethylated in six out of 32 (19%) primary invasive breast carcinomas and eight out of 44 (18%) primary clear cell renal cell carcinomas (CC-RCC) and in one out of 26 (4%) primary NSCLC tumours. Furthermore 80% of breast and 75% of CC-RCC tumours showing DUTT1 methylation had allelic losses for 3p12 markers hence obeying Knudson's two hit hypothesis. Our findings suggest that DUTT1 warrants further analysis as a candidate for

A novel genome-wide in vivo screen for metastatic suppressors in human colon cancer identifies the positive WNT-TCF pathway modulators TMED3 and SOX12

PubMed Central

Duquet, Arnaud; Melotti, Alice; Mishra, Sonakshi; Malerba, Monica; Seth, Chandan; Conod, Arwen; Ruiz i Altaba, Ariel

2014-01-01

The progression of tumors to the metastatic state involves the loss of metastatic suppressor functions. Finding these, however, is difficult as in vitro assays do not fully predict metastatic behavior, and the majority of studies have used cloned cell lines, which do not reflect primary tumor heterogeneity. Here, we have designed a novel genome-wide screen to identify metastatic suppressors using primary human tumor cells in mice, which allows saturation screens. Using this unbiased approach, we have tested the hypothesis that endogenous colon cancer metastatic suppressors affect WNT-TCF signaling. Our screen has identified two novel metastatic suppressors: TMED3 and SOX12, the knockdown of which increases metastatic growth after direct seeding. Moreover, both modify the type of self-renewing spheroids, but only knockdown of TMED3 also induces spheroid cell spreading and lung metastases from a subcutaneous xenograft. Importantly, whereas TMED3 and SOX12 belong to different families involved in protein secretion and transcriptional regulation, both promote endogenous WNT-TCF activity. Treatments for advanced or metastatic colon cancer may thus not benefit from WNT blockers, and these may promote a worse outcome. PMID:24920608

Polysaccharide Agaricus blazei Murill stimulates myeloid derived suppressor cell differentiation from M2 to M1 type, which mediates inhibition of tumour immune-evasion via the Toll-like receptor 2 pathway.

PubMed

Liu, Yi; Zhang, Lingyun; Zhu, Xiangxiang; Wang, Yuehua; Liu, WenWei; Gong, Wei

2015-11-01

Gr-1(+) CD11b(+) myeloid-derived suppressor cells (MDSCs) accumulate in tumor-bearing animals and play a critical negative role during tumor immunotherapy. Strategies for inhibition of MDSCs are expected to improve cancer immunotherapy. Polysaccharide Agaricus blazei Murill (pAbM) has been found to have anti-cancer activity, but the underlying mechanism of this is poorly understood. Here, pAbM directly activated the purified MDSCs through inducing the expression of interleukin-6 (IL-6), IL-12, tumour necrosis factor and inducible nitric oxide synthase (iNOS), CD86, MHC II, and pSTAT1 of it, and only affected natural killer and T cells in the presence of Gr-1(+) CD11b(+) monocytic MDSCs. On further analysis, we demonstrated that pAbM could selectively block the Toll-like receptor 2 (TLR2) signal of Gr-1(+) CD11b(+) MDSCs and increased their M1-type macrophage characteristics, such as producing IL-12, lowering expression of Arginase 1 and increasing expression of iNOS. Extensive study showed that Gr-1(+) CD11b(+) MDSCs by pAbM treatment had less ability to convert the CD4(+) CD25(-) cells into CD4(+) CD25(+) phenotype. Moreover, result from selective depletion of specific cell populations in xenograft mice model suggested that the anti-tumour effect of pAbM was dependent on Gr-1(+ ) CD11b(+) monocytes, nether CD8(+) T cells nor CD4(+) T cells. In addition to, pAbM did not inhibit tumour growth in TLR2(-/-) mice. All together, these results suggested that pAbM, a natural product commonly used for cancer treatment, was a specific TLR2 agonist and had potent anti-tumour effects through the opposite of the suppressive function of Gr-1(+) CD11b(+) MDSCs. © 2015 John Wiley & Sons Ltd.

An evidence-based knowledgebase of metastasis suppressors to identify key pathways relevant to cancer metastasis

PubMed Central

Zhao, Min; Li, Zhe; Qu, Hong

2015-01-01

Metastasis suppressor genes (MS genes) are genes that play important roles in inhibiting the process of cancer metastasis without preventing growth of the primary tumor. Identification of these genes and understanding their functions are critical for investigation of cancer metastasis. Recent studies on cancer metastasis have identified many new susceptibility MS genes. However, the comprehensive illustration of diverse cellular processes regulated by metastasis suppressors during the metastasis cascade is lacking. Thus, the relationship between MS genes and cancer risk is still unclear. To unveil the cellular complexity of MS genes, we have constructed MSGene (http://MSGene.bioinfo-minzhao.org/), the first literature-based gene resource for exploring human MS genes. In total, we manually curated 194 experimentally verified MS genes and mapped to 1448 homologous genes from 17 model species. Follow-up functional analyses associated 194 human MS genes with epithelium/tissue morphogenesis and epithelia cell proliferation. In addition, pathway analysis highlights the prominent role of MS genes in activation of platelets and coagulation system in tumor metastatic cascade. Moreover, global mutation pattern of MS genes across multiple cancers may reveal common cancer metastasis mechanisms. All these results illustrate the importance of MSGene to our understanding on cell development and cancer metastasis. PMID:26486520

Multiple roles of glyoxalase 1-mediated suppression of methylglyoxal glycation in cancer biology-Involvement in tumour suppression, tumour growth, multidrug resistance and target for chemotherapy.

PubMed

Rabbani, Naila; Xue, Mingzhan; Weickert, Martin O; Thornalley, Paul J

2018-04-01

Glyoxalase 1 (Glo1) is part of the glyoxalase system in the cytoplasm of all human cells. It catalyses the glutathione-dependent removal of the endogenous reactive dicarbonyl metabolite, methylglyoxal (MG). MG is formed mainly as a side product of anaerobic glycolysis. It modifies protein and DNA to form mainly hydroimidazolone MG-H1 and imidazopurinone MGdG adducts, respectively. Abnormal accumulation of MG, dicarbonyl stress, increases adduct levels which may induce apoptosis and replication catastrophe. In the non-malignant state, Glo1 is a tumour suppressor protein and small molecule inducers of Glo1 expression may find use in cancer prevention. Increased Glo1 expression is permissive for growth of tumours with high glycolytic activity and is thereby a biomarker of tumour growth. High Glo1 expression is a cause of multi-drug resistance. It is produced by over-activation of the Nrf2 pathway and GLO1 amplification. Glo1 inhibitors are antitumour agents, inducing apoptosis and necrosis, and anoikis. Tumour stem cells and tumours with high flux of MG formation and Glo1 expression are sensitive to Glo1 inhibitor therapy. It is likely that MG-induced cell death contributes to the mechanism of action of current antitumour agents. Common refractory tumours have high prevalence of Glo1 overexpression for which Glo1 inhibitors may improve therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tumour angiogenesis is reduced in the Tc1 mouse model of Down Syndrome

PubMed Central

Reynolds, Louise E.; Watson, Alan R.; Baker, Marianne; Jones, Tania A.; D’Amico, Gabriela; Robinson, Stephen D.; Joffre, Carine; Garrido-Urbani, Sarah; Rodriguez-Manzaneque, Juan Carlos; Martino-Echarri, Estefanía; Aurrand-Lions, Michel; Sheer, Denise; Dagna-Bricarelli, Franca; Nizetic, Dean; McCabe, Christopher J.; Turnell, Andrew S.; Kermorgant, Stephanie; Imhof, Beat A.; Adams, Ralf; Fisher, Elizabeth M.C.; Tybulewicz, Victor L. J.; Hart, Ian R.; Hodivala-Dilke, Kairbaan M.

2012-01-01

Down Syndrome (DS) is a genetic disorder caused by full or partial trisomy of chromosome 21. It occurs in approximately 1/750 live births and presents with many clinical phenotypes including a reduced incidence of solid tumours1,2. Recent work using the Ts65Dn model of DS, that has orthologs of approximately 50% of the genes on human chromosome 21 (Hsa21), has suggested that three copies of the ETS23 or Down Syndrome candidate region 1 (DSCR1) genes4 (a previously known suppressor of angiogenesis5,6) is sufficient to inhibit tumour growth. We have used the Tc1 transchromosomic mouse model of DS9 to dissect the contribution of extra copies of genes on Hsa21 to tumour angiogenesis. This mouse expresses approximately 81% of Hsa21 genes but not the human DSCR1 region (Supplementary Fig. 1). We transplanted B16F0 and Lewis Lung Carcinoma (LLC) tumour cells into Tc1 mice and showed that growth of these tumours was reduced substantially when compared to wild-type littermate controls. Furthermore, tumour angiogenesis was repressed significantly in Tc1 mice. In particular, in vitro and in vivo angiogenic responses to vascular endothelial growth factor (VEGF) were inhibited. Examination of the genes on the segment of Hsa21 in Tc1 mice identified putative anti-angiogenic genes (ADAMTS17,8 and ERG9) and novel endothelial cell-specific genes10, never shown before to be involved in angiogenesis (JAM-B11 and PTTG1IP) that, when overexpressed, are responsible for the inhibition of angiogenic responses to VEGF. Three copies of these genes within the stromal compartment reduced tumour angiogenesis providing an explanation for the reduced tumour growth in DS. Furthermore, we anticipate that, in addition to the candidate genes that we show to be involved in the repression of angiogenesis, the Tc1 mouse model of DS will likely allow for the identification of other endothelial-specific anti-angiogenic targets relevant to a broad spectrum of cancer patients. PMID:20535211

WWC3 regulates the Wnt and Hippo pathways via Dishevelled proteins and large tumour suppressor 1, to suppress lung cancer invasion and metastasis.

PubMed

Han, Qiang; Lin, Xuyong; Zhang, Xiupeng; Jiang, Guiyang; Zhang, Yong; Miao, Yuan; Rong, Xuezhu; Zheng, Xiaoying; Han, Yong; Han, Xu; Wu, Jingjing; Kremerskothen, Joachim; Wang, Enhua

2017-08-01

The scaffolding protein WWC (WW and C2-domain containing) family is known to regulate cell proliferation and organ size via the Hippo signalling pathway. However, the expression level of WWC3 in human tumours and the mechanisms underlying its role in cellular signal transduction have not yet been reported. Herein, we explored the potential roles of WWC3 in lung cancer cells and the corresponding molecular mechanisms. We found low WWC3 expression in both lung cancer cell lines and lung cancer specimens, which was associated with low differentiation, advanced pTNM stage, positive lymph node metastasis, and poor prognosis in patients with lung cancer. Moreover, the overexpression of WWC3 inhibited the proliferation and invasiveness of lung cancer cells. These effects were mediated by the inhibition and stimulation of the Wnt and Hippo pathways, respectively, in vitro and in vivo. Specifically, WWC3 interacts with Dishevelled (Dvl) proteins, prevents casein kinase 1ϵ from phosphorylating Dvls, and inhibits β-catenin nuclear translocation to inhibit the Wnt pathway. Deleting the WW and C-terminal PDZ-binding domains of WWC3 abrogated these effects. Moreover, the interaction of WWC3 with Dvls reduced the interaction between WWC3 and large tumour suppressor 1 (LATS1), as well as decreasing LATS1 phosphorylation to increase the nuclear importation of yes-associated protein (YAP) and attenuate the Hippo pathway. Deleting the WW domain of WWC3 abrogated this effect. These findings demonstrate the molecular interplay between WWC3, Dvls, and LATS1, and reveal a link between the Wnt and Hippo pathways, which provides a potential target for clinical intervention in lung cancer. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

The occurrence of intracranial rhabdoid tumours in mice depends on temporal control of Smarcb1 inactivation

PubMed Central

Han, Zhi-Yan; Richer, Wilfrid; Fréneaux, Paul; Chauvin, Céline; Lucchesi, Carlo; Guillemot, Delphine; Grison, Camille; Lequin, Delphine; Pierron, Gaelle; Masliah-Planchon, Julien; Nicolas, André; Ranchère-Vince, Dominique; Varlet, Pascale; Puget, Stéphanie; Janoueix-Lerosey, Isabelle; Ayrault, Olivier; Surdez, Didier; Delattre, Olivier; Bourdeaut, Franck

2016-01-01

Rhabdoid tumours (RTs) are highly aggressive tumours of infancy, frequently localized in the central nervous system (CNS) where they are termed atypical teratoid/rhabdoid tumours (AT/RTs) and characterized by bi-allelic inactivation of the SMARCB1 tumour suppressor gene. In this study, by temporal control of tamoxifen injection in Smarcb1flox/flox;Rosa26-CreERT2 mice, we explore the phenotypes associated with Smarcb1 inactivation at different developmental stages. Injection before E6, at birth or at 2 months of age recapitulates previously described phenotypes including embryonic lethality, hepatic toxicity or development of T-cell lymphomas, respectively. Injection between E6 and E10 leads to high penetrance tumours, mainly intra-cranial, with short delays (median: 3 months). These tumours demonstrate anatomical, morphological and gene expression profiles consistent with those of human AT/RTs. Moreover, intra- and inter-species comparisons of tumours reveal that human and mouse RTs can be split into different entities that may underline the variety of RT cells of origin. PMID:26818002

The occurrence of intracranial rhabdoid tumours in mice depends on temporal control of Smarcb1 inactivation.

PubMed

Han, Zhi-Yan; Richer, Wilfrid; Fréneaux, Paul; Chauvin, Céline; Lucchesi, Carlo; Guillemot, Delphine; Grison, Camille; Lequin, Delphine; Pierron, Gaelle; Masliah-Planchon, Julien; Nicolas, André; Ranchère-Vince, Dominique; Varlet, Pascale; Puget, Stéphanie; Janoueix-Lerosey, Isabelle; Ayrault, Olivier; Surdez, Didier; Delattre, Olivier; Bourdeaut, Franck

2016-01-28

Rhabdoid tumours (RTs) are highly aggressive tumours of infancy, frequently localized in the central nervous system (CNS) where they are termed atypical teratoid/rhabdoid tumours (AT/RTs) and characterized by bi-allelic inactivation of the SMARCB1 tumour suppressor gene. In this study, by temporal control of tamoxifen injection in Smarcb1(flox/flox);Rosa26-Cre(ERT2) mice, we explore the phenotypes associated with Smarcb1 inactivation at different developmental stages. Injection before E6, at birth or at 2 months of age recapitulates previously described phenotypes including embryonic lethality, hepatic toxicity or development of T-cell lymphomas, respectively. Injection between E6 and E10 leads to high penetrance tumours, mainly intra-cranial, with short delays (median: 3 months). These tumours demonstrate anatomical, morphological and gene expression profiles consistent with those of human AT/RTs. Moreover, intra- and inter-species comparisons of tumours reveal that human and mouse RTs can be split into different entities that may underline the variety of RT cells of origin.

Sinonasal haemangiopericytoma-like tumour: a sinonasal glomus tumour or a haemangiopericytoma?

PubMed

Tse, L L Y; Chan, J K C

2002-06-01

Sinonasal haemangiopericytoma-like tumour is controversial with regard to its nosologic nature. This study aims to investigate its relationship with glomus tumour and haemangiopericytoma. Six cases of sinonasal haemangiopericytoma-like tumours identified in our files were reviewed for clinicopathological features, and compared with five cases each of soft tissue glomus tumour and meningeal haemangiopericytoma. Immunohistochemical studies for muscle-specific actin, smooth muscle actin, desmin and CD34 were performed. Sinonasal haemangiopericytoma-like tumour demonstrated a uniform histological appearance with bland-looking short, spindly cells forming sheets and short fascicles. The tumour cells were interspersed with slit-like, round and ectatic blood vessels. Actin immunoreactivity was demonstrated in all six cases, although occasionally patchy. The histological appearance and immunohistochemical phenotype of sinonasal haemangiopericytoma-like tumour were very similar to and focally indistinguishable from glomus tumour. Meningeal haemangiopericytoma, in contrast, was characterized by high tumour cellularity, random nuclear orientation, presence of staghorn vasculature and lack of immunohistochemical evidence of myogenic differentiation. We conclude that sinonasal haemangiopericytoma-like tumour is biologically close to or identical to glomus tumour, but is not related to haemangiopericytoma.

Immunity to tumour antigens.

PubMed

Li, Geng; Ali, Selman A; McArdle, Stephanie E B; Mian, Shahid; Ahmad, Murrium; Miles, Amanda; Rees, Robert C

2005-01-01

During the last decade, a large number of human tumour antigens have been identified. These antigens are classified as tumour-specific shared antigens, tissue-specific differentiation antigens, overexpressed antigens, tumour antigens resulting from mutations, viral antigens and fusion proteins. Antigens recognised by effectors of immune system are potential targets for antigen-specific cancer immunotherapy. However, most tumour antigens are self-proteins and are generally of low immunogenicity and the immune response elicited towards these tumour antigens is not always effective. Strategies to induce and enhance the tumour antigen-specific response are needed. This review will summarise the approaches to discovery of tumour antigens, the current status of tumour antigens, and their potential application to cancer treatment.

SPRED1, a RAS MAPK pathway inhibitor that causes Legius syndrome, is a tumour suppressor downregulated in paediatric acute myeloblastic leukaemia.

PubMed

Pasmant, E; Gilbert-Dussardier, B; Petit, A; de Laval, B; Luscan, A; Gruber, A; Lapillonne, H; Deswarte, C; Goussard, P; Laurendeau, I; Uzan, B; Pflumio, F; Brizard, F; Vabres, P; Naguibvena, I; Fasola, S; Millot, F; Porteu, F; Vidaud, D; Landman-Parker, J; Ballerini, P

2015-01-29

Constitutional dominant loss-of-function mutations in the SPRED1 gene cause a rare phenotype referred as neurofibromatosis type 1 (NF1)-like syndrome or Legius syndrome, consisted of multiple café-au-lait macules, axillary freckling, learning disabilities and macrocephaly. SPRED1 is a negative regulator of the RAS MAPK pathway and can interact with neurofibromin, the NF1 gene product. Individuals with NF1 have a higher risk of haematological malignancies. SPRED1 is highly expressed in haematopoietic cells and negatively regulates haematopoiesis. SPRED1 seemed to be a good candidate for leukaemia predisposition or transformation. We performed SPRED1 mutation screening and expression status in 230 paediatric lymphoblastic and acute myeloblastic leukaemias (AMLs). We found a loss-of-function frameshift SPRED1 mutation in a patient with Legius syndrome. In this patient, the leukaemia blasts karyotype showed a SPRED1 loss of heterozygosity, confirming SPRED1 as a tumour suppressor. Our observation confirmed that acute leukaemias are rare complications of the Legius syndrome. Moreover, SPRED1 was significantly decreased at RNA and protein levels in the majority of AMLs at diagnosis compared with normal or paired complete remission bone marrows. SPRED1 decreased expression correlated with genetic features of AML. Our study reveals a new mechanism which contributes to deregulate RAS MAPK pathway in the vast majority of paediatric AMLs.

SomInaClust: detection of cancer genes based on somatic mutation patterns of inactivation and clustering.

PubMed

Van den Eynden, Jimmy; Fierro, Ana Carolina; Verbeke, Lieven P C; Marchal, Kathleen

2015-04-23

With the advances in high throughput technologies, increasing amounts of cancer somatic mutation data are being generated and made available. Only a small number of (driver) mutations occur in driver genes and are responsible for carcinogenesis, while the majority of (passenger) mutations do not influence tumour biology. In this study, SomInaClust is introduced, a method that accurately identifies driver genes based on their mutation pattern across tumour samples and then classifies them into oncogenes or tumour suppressor genes respectively. SomInaClust starts from the observation that oncogenes mainly contain mutations that, due to positive selection, cluster at similar positions in a gene across patient samples, whereas tumour suppressor genes contain a high number of protein-truncating mutations throughout the entire gene length. The method was shown to prioritize driver genes in 9 different solid cancers. Furthermore it was found to be complementary to existing similar-purpose methods with the additional advantages that it has a higher sensitivity, also for rare mutations (occurring in less than 1% of all samples), and it accurately classifies candidate driver genes in putative oncogenes and tumour suppressor genes. Pathway enrichment analysis showed that the identified genes belong to known cancer signalling pathways, and that the distinction between oncogenes and tumour suppressor genes is biologically relevant. SomInaClust was shown to detect candidate driver genes based on somatic mutation patterns of inactivation and clustering and to distinguish oncogenes from tumour suppressor genes. The method could be used for the identification of new cancer genes or to filter mutation data for further data-integration purposes.

Leukaemia cell of origin identified by chromatin landscape of bulk tumour cells

PubMed Central

George, Joshy; Uyar, Asli; Young, Kira; Kuffler, Lauren; Waldron-Francis, Kaiden; Marquez, Eladio; Ucar, Duygu; Trowbridge, Jennifer J.

2016-01-01

The precise identity of a tumour's cell of origin can influence disease prognosis and outcome. Methods to reliably define tumour cell of origin from primary, bulk tumour cell samples has been a challenge. Here we use a well-defined model of MLL-rearranged acute myeloid leukaemia (AML) to demonstrate that transforming haematopoietic stem cells (HSCs) and multipotent progenitors results in more aggressive AML than transforming committed progenitor cells. Transcriptome profiling reveals a gene expression signature broadly distinguishing stem cell-derived versus progenitor cell-derived AML, including genes involved in immune escape, extravasation and small GTPase signal transduction. However, whole-genome profiling of open chromatin reveals precise and robust biomarkers reflecting each cell of origin tested, from bulk AML tumour cell sampling. We find that bulk AML tumour cells exhibit distinct open chromatin loci that reflect the transformed cell of origin and suggest that open chromatin patterns may be leveraged as prognostic signatures in human AML. PMID:27397025

Loss of heterozygosity at 7p in Wilms' tumour development

PubMed Central

Powlesland, R M; Charles, A K; Malik, K T A; Reynolds, P A; Pires, S; Boavida, M; Brown, K W

2000-01-01

Chromosome 7p alterations have been implicated in the development of Wilms' tumour (WT) by previous studies of tumour cytogenetics, and by our analysis of a constitutional translocation (t(1;7)(q42;p15)) in a child with WT and radial aplasia. We therefore used polymorphic microsatellite markers on 7p for a loss of heterozygosity (LOH) study, and found LOH in seven out of 77 informative WTs (9%). The common region of LOH was 7p15–7p22, which contains the region disrupted by the t(1;7) breakpoint. Four WTs with 7p LOH had other genetic changes; a germline WT1 mutation with 11p LOH, LOH at 11p, LOH at 16q, and loss of imprinting of IGF2. Analysis of three tumour-associated lesions from 7p LOH cases revealed a cystic nephroma-like area also having 7p LOH. However, a nephrogenic rest and a contralateral WT from the two other cases showed no 7p LOH. No particular clinical phenotype was associated with the WTs which showed 7p LOH. The frequency and pattern of 7p LOH demonstrated in our studies indicate the presence of a tumour suppressor gene at 7p involved in the development of Wilms' tumour. © 2000 Cancer Research Campaign PMID:10646884

[Alterations of c-Myc and c-erbB-2 genes in ovarian tumours].

PubMed

Pastor, Tibor; Popović, Branka; Gvozdenović, Ana; Boro, Aleksandar; Petrović, Bojana; Novaković, Ivana; Puzović, Dragana; Luković, Ljiljana; Milasin, Jelena

2009-01-01

According to clinical and epidemiological studies, ovarian cancer ranks fifth in cancer deaths among women. The causes of ovarian cancer remain largely unknown but various factors may increase the risk of developing it, such as age, family history of cancer, childbearing status etc. This cancer results from a succession of genetic alterations involving oncogenes and tumour suppressor genes, which have a critical role in normal cell growth regulation. Mutations and/or overexpression of three oncogenes, c-erbB-2, c-Myc and K-ras, and of the tumour suppressor gene p53, have been frequently observed in a sporadic ovarian cancer. The aim of the present study was to analyse c-Myc and c-erbB-2 oncogene alterations, specifically amplification, as one of main mechanisms of their activation in ovarian cancers and to establish a possible association with the pathogenic process. DNA was isolated from 15 samples of malignant and 5 benign ovarian tumours, using proteinase K digestion, followed by phenol-chloroform isoamyl extraction and ethanol precipitation. C-Myc and c-erbB-2 amplification were detected by differential PCR. The level of gene copy increase was measured using the Scion image software. The amplification of both c-Myc and c-erbB-2 was detected in 26.7% of ovarian epithelial carcinoma specimens. Only one tumour specimen concomitantly showed increased gene copy number for both studied genes. Interestingly, besides amplification, gene deletion was also detected (26.7% for c-erbB-2). Most of the ovarian carcinomas with alterations in c-Myc and c-erbB-2 belonged to advanced FIGO stages. The amplification of c-Myc and c-erbB-2 oncogenes in ovarian epithelial carcinomas is most probably a late event in the pathogenesis conferring these tumours a more aggressive biological behaviour. Similarly, gene deletions point to genomic instability in epithelial carcinomas in higher clinical stages as the result of clonal evolution and selection.

The contribution of tumour-derived exosomes to the hallmarks of cancer.

PubMed

Meehan, Katie; Vella, Laura J

2016-01-01

Exosomes are small, biologically active extracellular vesicles and over the last decade, both stromal and tumour-derived exosomes (TDE) have been implicated in cancer onset, progression and metastases. Cancer is a complex disease that is underpinned by several "cancer hallmarks", originally described by Hanahan and Weinberg in 2000 and then revised in 2011. The hallmarks of cancer comprise six biological capabilities, along with two emerging hallmarks and two enabling characteristics that facilitate tumour growth and metastatic dissemination. Ample evidence supports a clear role for TDE in four of the original biological hallmarks (sustaining proliferative signalling, resisting cell death, inducing angiogenesis and activating invasion and metastases). A less-defined role exists for TDE in evading growth suppressors, and currently, there is no evidence to suggest a role for TDE in enabling replicative immortality. TDE are intimately involved in the newly defined hallmarks of cancer and enabling characteristics, most evidently in immune inhibition and tumour-promoting inflammation, which ultimately enable escape from immune destruction and tumour progression. Herein, we discuss the role of TDE in the context of the hallmarks and enabling characteristics of cancer as defined by Hanahan and Weinberg.

The tumour suppressor protein, p53, is involved in the activation of the apoptotic cascade by Delta9-tetrahydrocannabinol in cultured cortical neurons.

PubMed

Downer, Eric J; Gowran, Aoife; Murphy, Aine C; Campbell, Veronica A

2007-06-14

Cannabis is the most commonly used illegal drug of abuse in Western society. Delta(9)-tetrahydrocannabinol, the psychoactive ingredient of marijuana, regulates a variety of neuronal processes including neurotransmitter release and synaptic transmission. An increasing body of evidence suggests that cannabinoids play a key role in the regulation of neuronal viability. In cortical neurons tetrahydrocannabinol has a neurodegenerative effect, the mechanisms of which are poorly understood, but involve the cannabinoid receptor subtype, CB(1). In this study we report that tetrahydrocannabinol (5 muM) evokes a rapid phosphorylation, and thus activation, of the tumour suppressor protein, p53, in a manner involving the cannabinoid CB(1) receptor, and the stress-activated protein kinase, c-jun N-terminal kinase, in cultured cortical neurons. Tetrahydrocannabinol increased expression of the p53-transcriptional target, Bax and promoted Bcl phosphorylation. These events were abolished by the p53 inhibitor, pifithrin-alpha (100 nM). The tetrahydrocannabinol-induced activation of the pro-apoptotic cysteine protease, caspase-3, and DNA fragmentation was also blocked by pifithrin-alpha. A siRNA knockdown of p53 further verified the role of p53 in tetrahydrocannabinol-induced apoptosis. This study demonstrates a novel cannabinoid signalling pathway involving p53 that culminates in neuronal apoptosis.

Evaluation of a functional epigenetic approach to identify promoter region methylation in phaeochromocytoma and neuroblastoma

PubMed Central

Margetts, Caroline D E; Morris, Mark; Astuti, Dewi; Gentle, Dean C; Cascon, Alberto; McRonald, Fiona E; Catchpoole, Daniel; Robledo, Mercedes; Neumann, Hartmut P H; Latif, Farida; Maher, Eamonn R

2008-01-01

The molecular genetics of inherited phaeochromocytoma have received considerable attention, but the somatic genetic and epigenetic events that characterise tumourigenesis in sporadic phaeochromocytomas are less well defined. Previously, we found considerable overlap between patterns of promoter region tumour suppressor gene (TSG) hypermethylation in two neural crest tumours, neuroblastoma and phaeochromocytoma. In order to identify candidate biomarkers and epigenetically inactivated TSGs in phaeochromocytoma and neuroblastoma, we characterised changes in gene expression in three neuroblastoma cell lines after treatment with the demethylating agent 5-azacytidine. Promoter region methylation status was then determined for 28 genes that demonstrated increased expression after demethylation. Three genes HSP47, homeobox A9 (HOXA9) and opioid binding protein (OPCML) were methylated in >10% of phaeochromocytomas (52, 17 and 12% respectively). Two of the genes, epithelial membrane protein 3 (EMP3) and HSP47, demonstrated significantly more frequent methylation in neuroblastoma than phaeochromocytoma. These findings extend epigenotype of phaeochromocytoma and identify candidate genes implicated in sporadic phaeochromocytoma tumourigenesis. PMID:18499731

Polysaccharide Agaricus blazei Murill stimulates myeloid derived suppressor cell differentiation from M2 to M1 type, which mediates inhibition of tumour immune-evasion via the Toll-like receptor 2 pathway

PubMed Central

Liu, Yi; Zhang, Lingyun; Zhu, Xiangxiang; Wang, Yuehua; Liu, WenWei; Gong, Wei

2015-01-01

Gr-1+ CD11b+ myeloid-derived suppressor cells (MDSCs) accumulate in tumor-bearing animals and play a critical negative role during tumor immunotherapy. Strategies for inhibition of MDSCs are expected to improve cancer immunotherapy. Polysaccharide Agaricus blazei Murill (pAbM) has been found to have anti-cancer activity, but the underlying mechanism of this is poorly understood. Here, pAbM directly activated the purified MDSCs through inducing the expression of interleukin-6 (IL-6), IL-12, tumour necrosis factor and inducible nitric oxide synthase (iNOS), CD86, MHC II, and pSTAT1 of it, and only affected natural killer and T cells in the presence of Gr-1+ CD11b+ monocytic MDSCs. On further analysis, we demonstrated that pAbM could selectively block the Toll-like receptor 2 (TLR2) signal of Gr-1+ CD11b+ MDSCs and increased their M1-type macrophage characteristics, such as producing IL-12, lowering expression of Arginase 1 and increasing expression of iNOS. Extensive study showed that Gr-1+ CD11b+ MDSCs by pAbM treatment had less ability to convert the CD4+ CD25− cells into CD4+ CD25+ phenotype. Moreover, result from selective depletion of specific cell populations in xenograft mice model suggested that the anti-tumour effect of pAbM was dependent on Gr-1+ CD11b+ monocytes, nether CD8+ T cells nor CD4+ T cells. In addition to, pAbM did not inhibit tumour growth in TLR2–/– mice. All together, these results suggested that pAbM, a natural product commonly used for cancer treatment, was a specific TLR2 agonist and had potent anti-tumour effects through the opposite of the suppressive function of Gr-1+ CD11b+ MDSCs. PMID:26194418

Genome-wide DNA methylation analysis identifies MEGF10 as a novel epigenetically repressed candidate tumor suppressor gene in neuroblastoma.

PubMed

Charlet, Jessica; Tomari, Ayumi; Dallosso, Anthony R; Szemes, Marianna; Kaselova, Martina; Curry, Thomas J; Almutairi, Bader; Etchevers, Heather C; McConville, Carmel; Malik, Karim T A; Brown, Keith W

2017-04-01

Neuroblastoma is a childhood cancer in which many children still have poor outcomes, emphasising the need to better understand its pathogenesis. Despite recent genome-wide mutation analyses, many primary neuroblastomas do not contain recognizable driver mutations, implicating alternate molecular pathologies such as epigenetic alterations. To discover genes that become epigenetically deregulated during neuroblastoma tumorigenesis, we took the novel approach of comparing neuroblastomas to neural crest precursor cells, using genome-wide DNA methylation analysis. We identified 93 genes that were significantly differentially methylated of which 26 (28%) were hypermethylated and 67 (72%) were hypomethylated. Concentrating on hypermethylated genes to identify candidate tumor suppressor loci, we found the cell engulfment and adhesion factor gene MEGF10 to be epigenetically repressed by DNA hypermethylation or by H3K27/K9 methylation in neuroblastoma cell lines. MEGF10 showed significantly down-regulated expression in neuroblastoma tumor samples; furthermore patients with the lowest-expressing tumors had reduced relapse-free survival. Our functional studies showed that knock-down of MEGF10 expression in neuroblastoma cell lines promoted cell growth, consistent with MEGF10 acting as a clinically relevant, epigenetically deregulated neuroblastoma tumor suppressor gene. © 2016 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc. © 2016 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc.

Genome‐wide DNA methylation analysis identifies MEGF10 as a novel epigenetically repressed candidate tumor suppressor gene in neuroblastoma

PubMed Central

Charlet, Jessica; Tomari, Ayumi; Dallosso, Anthony R.; Szemes, Marianna; Kaselova, Martina; Curry, Thomas J.; Almutairi, Bader; Etchevers, Heather C.; McConville, Carmel; Malik, Karim T. A.

2016-01-01

Neuroblastoma is a childhood cancer in which many children still have poor outcomes, emphasising the need to better understand its pathogenesis. Despite recent genome‐wide mutation analyses, many primary neuroblastomas do not contain recognizable driver mutations, implicating alternate molecular pathologies such as epigenetic alterations. To discover genes that become epigenetically deregulated during neuroblastoma tumorigenesis, we took the novel approach of comparing neuroblastomas to neural crest precursor cells, using genome‐wide DNA methylation analysis. We identified 93 genes that were significantly differentially methylated of which 26 (28%) were hypermethylated and 67 (72%) were hypomethylated. Concentrating on hypermethylated genes to identify candidate tumor suppressor loci, we found the cell engulfment and adhesion factor gene MEGF10 to be epigenetically repressed by DNA hypermethylation or by H3K27/K9 methylation in neuroblastoma cell lines. MEGF10 showed significantly down‐regulated expression in neuroblastoma tumor samples; furthermore patients with the lowest‐expressing tumors had reduced relapse‐free survival. Our functional studies showed that knock‐down of MEGF10 expression in neuroblastoma cell lines promoted cell growth, consistent with MEGF10 acting as a clinically relevant, epigenetically deregulated neuroblastoma tumor suppressor gene. © 2016 The Authors. Molecular Carcinogenesis Published by Wiley Periodicals, Inc. PMID:27862318

Regulation of tumour related genes by dynamic epigenetic alteration at enhancer regions in gastric epithelial cells infected by Epstein-Barr virus.

PubMed

Okabe, Atsushi; Funata, Sayaka; Matsusaka, Keisuke; Namba, Hiroe; Fukuyo, Masaki; Rahmutulla, Bahityar; Oshima, Motohiko; Iwama, Atsushi; Fukayama, Masashi; Kaneda, Atsushi

2017-08-11

Epstein-Barr virus (EBV) infection is associated with tumours such as Burkitt lymphoma, nasopharyngeal carcinoma, and gastric cancer. We previously showed that EBV(+) gastric cancer presents an extremely high-methylation epigenotype and this aberrant DNA methylation causes silencing of multiple tumour suppressor genes. However, the mechanisms that drive EBV infection-mediated tumorigenesis, including other epigenomic alteration, remain unclear. We analysed epigenetic alterations induced by EBV infection especially at enhancer regions, to elucidate their contribution to tumorigenesis. We performed ChIP sequencing on H3K4me3, H3K4me1, H3K27ac, H3K27me3, and H3K9me3 in gastric epithelial cells infected or not with EBV. We showed that repressive marks were redistributed after EBV infection, resulting in aberrant enhancer activation and repression. Enhancer dysfunction led to the activation of pathways related to cancer hallmarks (e.g., resisting cell death, disrupting cellular energetics, inducing invasion, evading growth suppressors, sustaining proliferative signalling, angiogenesis, and tumour-promoting inflammation) and inactivation of tumour suppressive pathways. Deregulation of cancer-related genes in EBV-infected gastric epithelial cells was also observed in clinical EBV(+) gastric cancer specimens. Our analysis showed that epigenetic alteration associated with EBV-infection may contribute to tumorigenesis through enhancer activation and repression.

Suppressors of systemin signaling identify genes in the tomato wound response pathway.

PubMed Central

Howe, G A; Ryan, C A

1999-01-01

In tomato plants, systemic induction of defense genes in response to herbivory or mechanical wounding is regulated by an 18-amino-acid peptide signal called systemin. Transgenic plants that overexpress prosystemin, the systemin precursor, from a 35S::prosystemin (35S::prosys) transgene exhibit constitutive expression of wound-inducible defense proteins including proteinase inhibitors and polyphenol oxidase. To study further the role of (pro)systemin in the wound response pathway, we isolated and characterized mutations that suppress 35S::prosys-mediated phenotypes. Ten recessive, extragenic suppressors were identified. Two of these define new alleles of def-1, a previously identified mutation that blocks both wound- and systemin-induced gene expression and renders plants susceptible to herbivory. The remaining mutants defined four loci designated Spr-1, Spr-2, Spr-3, and Spr-4 (for Suppressed in 35S::prosystemin-mediated responses). spr-3 and spr-4 mutants were not significantly affected in their response to either systemin or mechanical wounding. In contrast, spr-1 and spr-2 plants lacked systemic wound responses and were insensitive to systemin. These results confirm the function of (pro)systemin in the transduction of systemic wound signals and further establish that wounding, systemin, and 35S::prosys induce defensive gene expression through a common signaling pathway defined by at least three genes (Def-1, Spr-1, and Spr-2). PMID:10545469

The Parkinson disease-related protein DJ-1 counteracts mitochondrial impairment induced by the tumour suppressor protein p53 by enhancing endoplasmic reticulum-mitochondria tethering.

PubMed

Ottolini, Denis; Calì, Tito; Negro, Alessandro; Brini, Marisa

2013-06-01

DJ-1 was first identified as an oncogene. More recently, mutations in its gene have been found causative for autosomal recessive familial Parkinson disease. Numerous studies support the DJ-1 role in the protection against oxidative stress and maintenance of mitochondria structure; however, the mechanism of its protective function remains largely unknown. We investigated whether mitochondrial Ca(2+) homeostasis, a key parameter in cell physiology, could be a target for DJ-1 action. Here, we show that DJ-1 modulates mitochondrial Ca(2+) transients induced upon cell stimulation with an 1,4,5-inositol-tris-phosphate agonist by favouring the endoplasmic reticulum (ER)-mitochondria tethering. A reduction of DJ-1 levels results in mitochondria fragmentation and decreased mitochondrial Ca(2+) uptake in stimulated cells. To functionally couple these effects with the well-recognized cytoprotective role of DJ-1, we investigated its action in respect to the tumour suppressor p53. p53 overexpression in HeLa cells impairs their ability to accumulate Ca(2+) in the mitochondrial matrix, causes alteration of the mitochondrial morphology and reduces ER-mitochondria contact sites. Mitochondrial impairments are independent from Drp1 activation, since the co-expression of the dominant negative mutant of Drp1 failed to abolish them. DJ-1 overexpression prevents these alterations by re-establishing the ER-mitochondria tethering. Similarly, the co-expression of the pro-fusion protein Mitofusin 2 blocks the effects induced by p53 on mitochondria, confirming that the modulation of the ER-mitochondria contact sites is critical to mitochondria integrity. Thus, the impairment of ER-mitochondria communication, as a consequence of DJ-1 loss-of-function, may be detrimental for mitochondria-related processes and be at the basis of mitochondrial dysfunction observed in Parkinson disease.

Expression of p16(INK4A) gene in human pituitary tumours.

PubMed

Machiavelli, Gloria; Cotignola, Javier; Danilowicz, Karina; Carbonara, Carolina; Paes de Lima, Andrea; Basso, Armando; Bruno, Oscar Domingo; Szijan, Irene

2008-01-01

Pituitary adenomas comprise 10-15% of primary intracranial tumours but the mechanisms leading to tumour development are yet to be clearly established. The retinoblastoma pathway, which regulates the progression through the cell cycle, is often deregulated in different types of tumours. We studied the cyclin-dependent kinase inhibitor p16(INK4A) gene expression at mRNA level in human pituitary adenomas. Forty-six tumour specimens of different subtypes, 21 clinically non-functioning, 12 growth hormone-secreting, 6 prolactin-secreting, 6 adrenocorticotropin-secreting, and 1 thyrotropin-secreting tumours were studied. All clinically non-functioning and most of the hormone-secreting tumours were macroadenomas (38/46). The RT-PCR assay and electrophoresis of the PCR-products showed that p16(INK4A) mRNA was undetectable in: 62% of non-functioning, 8% of growth hormone-secreting, 17% of prolactin-secreting and 17% of adrenocorticotropin-secreting adenomas. Forty percent of all macroadenomas and 25% of microadenomas had negative p16(INK4A) mRNA, the latter results suggest that the absence of p16(INK4A) product might be an early event in tumours with no expression of this suppressor gene. Within the non-functioning adenomas 63% were "null cell" and 37% were positive for some hormone, both subgroups showed similar percentage of cases with absence of p16(INK4A) mRNA. Our results show that clinically non-functioning macroadenomas have impaired p16(INK4A) expression in a clearly higher proportion than any other pituitary tumour subtype investigated. Other regulatory pathways may be implicated in the development of tumours with positive p16(INK4A) expression.

HumanMethylation450K Array–Identified Biomarkers Predict Tumour Recurrence/Progression at Initial Diagnosis of High-risk Non-muscle Invasive Bladder Cancer

PubMed Central

Kitchen, Mark O; Bryan, Richard T; Emes, Richard D; Luscombe, Christopher J; Cheng, KK; Zeegers, Maurice P; James, Nicholas D; Gommersall, Lyndon M; Fryer, Anthony A

2018-01-01

Background: High-risk non-muscle invasive bladder cancer (HR-NMIBC) is a clinically unpredictable disease. Despite clinical risk estimation tools, many patients are undertreated with intra-vesical therapies alone, whereas others may be over-treated with early radical surgery. Molecular biomarkers, particularly DNA methylation, have been reported as predictive of tumour/patient outcomes in numerous solid organ and haematologic malignancies; however, there are few reports in HR-NMIBC and none using genome-wide array assessment. We therefore sought to identify novel DNA methylation markers of HR-NMIBC clinical outcomes that might predict tumour behaviour at initial diagnosis and help guide patient management. Patients and methods: A total of 21 primary initial diagnosis HR-NMIBC tumours were analysed by Illumina HumanMethylation450 BeadChip arrays and subsequently bisulphite Pyrosequencing. In all, 7 had not recurred at 1 year after resection and 14 had recurred and/or progressed despite intra-vesical BCG. A further independent cohort of 32 HR-NMIBC tumours (17 no recurrence and 15 recurrence and/or progression despite BCG) were also assessed by bisulphite Pyrosequencing. Results: Array analyses identified 206 CpG loci that segregated non-recurrent HR-NMIBC tumours from clinically more aggressive recurrence/progression tumours. Hypermethylation of CpG cg11850659 and hypomethylation of CpG cg01149192 in combination predicted HR-NMIBC recurrence and/or progression within 1 year of diagnosis with 83% sensitivity, 79% specificity, and 83% positive and 79% negative predictive values. Conclusions: This is the first genome-wide DNA methylation analysis of a unique HR-NMIBC tumour cohort encompassing known 1-year clinical outcomes. Our analyses identified potential novel epigenetic markers that could help guide individual patient management in this clinically unpredictable disease. PMID:29343995

Endocrine tumours in neurofibromatosis type 1, tuberous sclerosis and related syndromes.

PubMed

Lodish, Maya B; Stratakis, Constantine A

2010-06-01

Neurofibromatosis type 1 (NF-1) and tuberous sclerosis complex (TSC) are two familial syndromes known as phakomatoses that may be associated with endocrine tumours. These hereditary cutaneous conditions affect the central nervous system and are characterised by the development of hamartomas. Over the past 20 years, there have been major advances in our understanding of the molecular basis of these diseases. Both NF-1 and TSC are disorders of unregulated progression through the cell cycle, in which causative genes behave as tumour suppressor genes. The pathogenesis of these familial syndromes is linked by the shared regulation of a common pathway, the protein kinase mammalian target of rapamycin (mTOR). Additional related disorders that also converge on the mTOR pathway include Peutz-Jeghers syndrome and Cowden syndrome. All of these inherited cancer syndromes are associated with characteristic skin findings that offer a clue to their recognition and treatment. The discovery of mTOR inhibitors has led to a possible new therapeutic modality for patients with endocrine tumours as part of these familial syndromes. Published by Elsevier Ltd.

p53 status determines the role of autophagy in pancreatic tumour development

NASA Astrophysics Data System (ADS)

Rosenfeldt, Mathias T.; O'Prey, Jim; Morton, Jennifer P.; Nixon, Colin; Mackay, Gillian; Mrowinska, Agata; Au, Amy; Rai, Taranjit Singh; Zheng, Liang; Ridgway, Rachel; Adams, Peter D.; Anderson, Kurt I.; Gottlieb, Eyal; Sansom, Owen J.; Ryan, Kevin M.

2013-12-01

Macroautophagy (hereafter referred to as autophagy) is a process in which organelles termed autophagosomes deliver cytoplasmic constituents to lysosomes for degradation. Autophagy has a major role in cellular homeostasis and has been implicated in various forms of human disease. The role of autophagy in cancer seems to be complex, with reports indicating both pro-tumorigenic and tumour-suppressive roles. Here we show, in a humanized genetically-modified mouse model of pancreatic ductal adenocarcinoma (PDAC), that autophagy's role in tumour development is intrinsically connected to the status of the tumour suppressor p53. Mice with pancreases containing an activated oncogenic allele of Kras (also called Ki-Ras)--the most common mutational event in PDAC--develop a small number of pre-cancerous lesions that stochastically develop into PDAC over time. However, mice also lacking the essential autophagy genes Atg5 or Atg7 accumulate low-grade, pre-malignant pancreatic intraepithelial neoplasia lesions, but progression to high-grade pancreatic intraepithelial neoplasias and PDAC is blocked. In marked contrast, in mice containing oncogenic Kras and lacking p53, loss of autophagy no longer blocks tumour progression, but actually accelerates tumour onset, with metabolic analysis revealing enhanced glucose uptake and enrichment of anabolic pathways, which can fuel tumour growth. These findings provide considerable insight into the role of autophagy in cancer and have important implications for autophagy inhibition in cancer therapy. In this regard, we also show that treatment of mice with the autophagy inhibitor hydroxychloroquine, which is currently being used in several clinical trials, significantly accelerates tumour formation in mice containing oncogenic Kras but lacking p53.

RET is a potential tumor suppressor gene in colorectal cancer

PubMed Central

Luo, Yanxin; Tsuchiya, Karen D.; Park, Dong Il; Fausel, Rebecca; Kanngurn, Samornmas; Welcsh, Piri; Dzieciatkowski, Slavomir; Wang, Jianping; Grady, William M.

2012-01-01

Cancer arises as the consequence of mutations and epigenetic alterations that activate oncogenes and inactivate tumor suppressor genes. Through a genome-wide screen for methylated genes in colon neoplasms, we identified aberrantly methylated RET in colorectal cancer. RET, a transmembrane receptor tyrosine kinase and a receptor for the GDNF-family ligands, was one of the first oncogenes to be identified and has been shown to be an oncogene in thyroid cancer and pheochromocytoma. However, unexpectedly, we found RET is methylated in 27% of colon adenomas and in 63% of colorectal cancers, and now provide evidence that RET has tumor suppressor activity in colon cancer. The aberrant methylation of RET correlates with decreased RET expression, whereas the restoration of RET in colorectal cancer cell lines results in apoptosis. Furthermore, in support of a tumor suppressor function of RET, mutant RET has also been found in primary colorectal cancer. We now show that these mutations inactivate RET, which is consistent with RET being a tumor suppressor gene in the colon. These findings suggest that the aberrant methylation of RET and the mutational inactivation of RET promote colorectal cancer formation and that RET can serve as a tumor suppressor gene in the colon. Moreover, the increased frequency of methylated RET in colon cancers compared to adenomas suggests RET inactivation is involved in the progression of colon adenomas to cancer. PMID:22751117

The Quest for the 1p36 Tumor Suppressor

PubMed Central

Bagchi, Anindya; Mills, Alea A.

2010-01-01

Genomic analyses of late-stage human cancers have uncovered deletions encompassing 1p36, thereby providing an extensive body of literature supporting the idea that a potent tumor suppressor resides in this interval. Although a number of genes have been proposed as 1p36 candidate tumor suppressors, convincing evidence that their encoded products protect from cancer has been scanty. A recent functional study identified CHD5 as a novel tumor suppressor mapping to 1p36. Here we discuss evidence supporting CHD5’s tumor suppressive role. Together, these findings suggest that strategies designed to enhance CHD5 activity could provide novel approaches for treating a broad range of human malignancies. PMID:18413720

Recurrent TERT promoter mutations identified in a large-scale study of multiple tumour types are associated with increased TERT expression and telomerase activation.

PubMed

Huang, Dong-Sheng; Wang, Zhaohui; He, Xu-Jun; Diplas, Bill H; Yang, Rui; Killela, Patrick J; Meng, Qun; Ye, Zai-Yuan; Wang, Wei; Jiang, Xiao-Ting; Xu, Li; He, Xiang-Lei; Zhao, Zhong-Sheng; Xu, Wen-Juan; Wang, Hui-Ju; Ma, Ying-Yu; Xia, Ying-Jie; Li, Li; Zhang, Ru-Xuan; Jin, Tao; Zhao, Zhong-Kuo; Xu, Ji; Yu, Sheng; Wu, Fang; Liang, Junbo; Wang, Sizhen; Jiao, Yuchen; Yan, Hai; Tao, Hou-Quan

2015-05-01

Several somatic mutation hotspots were recently identified in the telomerase reverse transcriptase (TERT) promoter region in human cancers. Large scale studies of these mutations in multiple tumour types are limited, in particular in Asian populations. This study aimed to: analyse TERT promoter mutations in multiple tumour types in a large Chinese patient cohort, investigate novel tumour types and assess the functional significance of the mutations. TERT promoter mutation status was assessed by Sanger sequencing for 13 different tumour types and 799 tumour tissues from Chinese cancer patients. Thymic epithelial tumours, gastrointestinal leiomyoma, and gastric schwannoma were included, for which the TERT promoter has not been previously sequenced. Functional studies included TERT expression by reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR), telomerase activity by the telomeric repeat amplification protocol (TRAP) assay and promoter activity by the luciferase reporter assay. TERT promoter mutations were highly frequent in glioblastoma (83.9%), urothelial carcinoma (64.5%), oligodendroglioma (70.0%), medulloblastoma (33.3%) and hepatocellular carcinoma (31.4%). C228T and C250T were the most common mutations. In urothelial carcinoma, several novel rare mutations were identified. TERT promoter mutations were absent in gastrointestinal stromal tumour (GIST), thymic epithelial tumours, gastrointestinal leiomyoma, gastric schwannoma, cholangiocarcinoma, gastric and pancreatic cancer. TERT promoter mutations highly correlated with upregulated TERT mRNA expression and telomerase activity in adult gliomas. These mutations differentially enhanced the transcriptional activity of the TERT core promoter. TERT promoter mutations are frequent in multiple tumour types and have similar distributions in Chinese cancer patients. The functional significance of these mutations reflect the importance to telomere maintenance and hence tumourigenesis, making them

Self-assembled RNA-triple-helix hydrogel scaffold for microRNA modulation in the tumour microenvironment

NASA Astrophysics Data System (ADS)

Conde, João; Oliva, Nuria; Atilano, Mariana; Song, Hyun Seok; Artzi, Natalie

2016-03-01

The therapeutic potential of miRNA (miR) in cancer is limited by the lack of efficient delivery vehicles. Here, we show that a self-assembled dual-colour RNA-triple-helix structure comprising two miRNAs--a miR mimic (tumour suppressor miRNA) and an antagomiR (oncomiR inhibitor)--provides outstanding capability to synergistically abrogate tumours. Conjugation of RNA triple helices to dendrimers allows the formation of stable triplex nanoparticles, which form an RNA-triple-helix adhesive scaffold upon interaction with dextran aldehyde, the latter able to chemically interact and adhere to natural tissue amines in the tumour. We also show that the self-assembled RNA-triple-helix conjugates remain functional in vitro and in vivo, and that they lead to nearly 90% levels of tumour shrinkage two weeks post-gel implantation in a triple-negative breast cancer mouse model. Our findings suggest that the RNA-triple-helix hydrogels can be used as an efficient anticancer platform to locally modulate the expression of endogenous miRs in cancer.

Epitope presentation is an important determinant of the utility of antigens identified from protein arrays in the development of autoantibody diagnostic assays.

PubMed

Murphy, Mairead A; O'Connell, David J; O'Kane, Sara L; O'Brien, John K; O'Toole, Sharon; Martin, Cara; Sheils, Orla; O'Leary, John J; Cahill, Dolores J

2012-08-03

Autoantibodies represent an attractive biomarker for diagnostic assays principally due to the stability of immunoglobulin in patient serum facilitating measurement with conventional assays. Immune responses to tumorigenesis may facilitate detection of ovarian cancer in the early stages of the disease with identification of a panel of tumour specific autoantibodies. Despite the reporting of many tumour associated autoantibodies using arrays of tumour antigens, this has not led to the advance in diagnostic capability as rapidly as was initially expected. Here we examine the potential diagnostic utility of candidate autoantibody biomarkers identified via screening of serum samples on a high content human protein array from a unique cohort of early stage and late stage ovarian cancer patients. We analyse the performance of autoantibodies to the tumour suppressor protein p53 and the novel autoantigens alpha adducin and endosulfine alpha identified in our array screen. Each antigen has different performance characteristics using conventional ELISA format and Western blot immunoassay. The high attrition rate of promising autoantigens identified by array screening can in part be explained by the presentation of the epitope of the antigen in the subsequent method of validation and this study provides directions on maximising the potential of candidate biomarkers. This article is part of a Special Issue entitled: Translational Proteomics. Copyright © 2012 Elsevier B.V. All rights reserved.

A putative OTU domain-containing protein 1 deubiquitinating enzyme is differentially expressed in thyroid cancer and identifies less-aggressive tumours

PubMed Central

Carneiro, A P; Reis, C F; Morari, E C; Maia, Y C P; Nascimento, R; Bonatto, J M C; de Souza, M A; Goulart, L R; Ward, L S

2014-01-01

Background: This study aimed to identify novel biomarkers for thyroid carcinoma diagnosis and prognosis. Methods: We have constructed a human single-chain variable fragment (scFv) antibody library that was selected against tumour thyroid cells using the BRASIL method (biopanning and rapid analysis of selective interactive ligands) and phage display technology. Results: One highly reactive clone, scFv-C1, with specific binding to papillary thyroid tumour proteins was confirmed by ELISA, which was further tested against a tissue microarray that comprised of 229 thyroid tissues, including: 110 carcinomas (38 papillary thyroid carcinomas (PTCs), 42 follicular carcinomas, 30 follicular variants of PTC), 18 normal thyroid tissues, 49 nodular goitres (NG) and 52 follicular adenomas. The scFv-C1 was able to distinguish carcinomas from benign lesions (P=0.0001) and reacted preferentially against T1 and T2 tumour stages (P=0.0108). We have further identified an OTU domain-containing protein 1, DUBA-7 deubiquitinating enzyme as the scFv-binding antigen using two-dimensional polyacrylamide gel electrophoresis and mass spectrometry. Conclusions: The strategy of screening and identifying a cell-surface-binding antibody against thyroid tissues was highly effective and resulted in a useful biomarker that recognises malignancy among thyroid nodules and may help identify lower-risk cases that can benefit from less-aggressive management. PMID:24937664

Phyllodes tumours

PubMed Central

Parker, S; Harries, S

2001-01-01

Phyllodes tumours are rare fibroepithelial lesions that account for less than 1% of all breast neoplasms. With the non-operative management of fibroadenomas widely adopted, the importance of phyllodes tumours today lies in the need to differentiate them from other benign breast lesions. All breast lumps should be triple assessed and the diagnosis of a phyllodes tumour considered in women, particularly over the age of 35 years, who present with a rapidly growing "benign" breast lump. Treatment can be by either wide excision or mastectomy provided histologically clear specimen margins are ensured. Nodal metastases are rare and routine axillary dissection is not recommended. Few reliable clinical and histological prognostic factors have been identified. Local recurrence occurs in approximately 15% of patients and is more common after incomplete excision. It can usually be controlled by further surgery. Repeated local recurrence has been reported without the development of distant metastases or reduced survival. Approximately 20% of patients with malignant phyllodes tumours develop distant metastases. Long term survival with distant metastases is rare. The role of chemotherapy, radiotherapy, and hormonal manipulation in both the adjuvant and palliative settings remain to be defined.


Keywords: benign breast disease; fibroadenoma; phyllodes tumour PMID:11423590

Global DNA methylation in fetal human germ cells and germ cell tumours: association with differentiation and cisplatin resistance.

PubMed

Wermann, Hendrik; Stoop, Hans; Gillis, Ad J M; Honecker, Friedemann; van Gurp, Ruud J H L M; Ammerpohl, Ole; Richter, Julia; Oosterhuis, J Wolter; Bokemeyer, Carsten; Looijenga, Leendert H J

2010-08-01

Differences in the global methylation pattern, ie hyper- as well as hypo-methylation, are observed in cancers including germ cell tumours (GCTs). Related to their precursor cells, GCT methylation status differs according to histology. We investigated the methylation pattern of normal fetal, infantile, and adult germ cells (n = 103) and GCTs (n = 251) by immunohistochemical staining for 5-(m)cytidine. The global methylation pattern of male germ cells changes from hypomethylation to hypermethylation, whereas female germ cells remain unmethylated at all stages. Undifferentiated GCTs (seminomas, intratubular germ cell neoplasia unclassified, and gonadoblastomas) are hypomethylated, whereas more differentiated GCTs (teratomas, yolk sac tumours, and choriocarcinomas) show a higher degree of methylation. Embryonal carcinomas show an intermediate pattern. Resistance to cisplatin was assessed in the seminomatous cell line TCam-2 before and after demethylation using 5-azacytidine. Exposure to 5-azacytidine resulted in decreased resistance to cisplatin. Furthermore, after demethylation, the stem cell markers NANOG and POU5F1 (OCT3/4), as well as the germ cell-specific marker VASA, showed increased expression. Following treatment with 5-azacytidine, TCam-2 cells were analysed using a high-throughput methylation screen for changes in the methylation sites of 14,000 genes. Among the genes revealing changes, interesting targets were identified: ie demethylation of KLF11, a putative tumour suppressor gene, and hypermethylation of CFLAR, a gene previously described in treatment resistance in GCTs.

Molecular pathology of bone tumours: diagnostic implications.

PubMed

Puls, Florian; Niblett, Angela J; Mangham, D Chas

2014-03-01

Alongside histomorphology and immunohistochemistry, molecular pathology is now established as one of the cornerstones in the tissue diagnosis of bone tumours. We describe the principal molecular pathological techniques employed, and each of the bone tumour entities where their identified characteristic molecular pathological changes can be detected to support and confirm the suspected histological diagnosis. Tumours discussed include fibrous dysplasia, classical and subtype osteosarcomas, central and surface cartilaginous tumours, Ewing's sarcoma, vascular tumours, aneurysmal bone cyst, chordoma, myoepithelioma, and angiomatoid fibrous histiocytoma. This is a rapidly evolving field with discoveries occurring every few months, and some of the newer entities (the Ewing's-like sarcomas), which are principally identified by their molecular pathology characteristics, are discussed. © 2013 John Wiley & Sons Ltd.

Suppressor Analysis of the Fusogenic Lambda Spanins.

PubMed

Cahill, Jesse; Rajaure, Manoj; Holt, Ashley; Moreland, Russell; O'Leary, Chandler; Kulkarni, Aneesha; Sloan, Jordan; Young, Ry

2017-07-15

The final step of lysis in phage λ infections of Escherichia coli is mediated by the spanins Rz and Rz1. These proteins form a complex that bridges the cell envelope and that has been proposed to cause fusion of the inner and outer membranes. Accordingly, mutations that block spanin function are found within coiled-coil domains and the proline-rich region, motifs essential in other fusion systems. To gain insight into spanin function, pseudorevertant alleles that restored plaque formation for lysis-defective mutants of Rz and Rz1 were selected. Most second-site suppressors clustered within a coiled-coil domain of Rz near the outer leaflet of the cytoplasmic membrane and were not allele specific. Suppressors largely encoded polar insertions within the hydrophobic core of the coiled-coil interface. Such suppressor changes resulted in decreased proteolytic stability of the Rz double mutants in vivo Unlike the wild type, in which lysis occurs while the cells retain a rod shape, revertant alleles with second-site suppressor mutations supported lysis events that were preceded by spherical cell formation. This suggests that destabilization of the membrane-proximal coiled coil restores function for defective spanin alleles by increasing the conformational freedom of the complex at the cost of its normal, all-or-nothing functionality. IMPORTANCE Caudovirales encode cell envelope-spanning proteins called spanins, which are thought to fuse the inner and outer membranes during phage lysis. Recent genetic analysis identified the functional domains of the lambda spanins, which are similar to class I viral fusion proteins. While the pre- and postfusion structures of model fusion systems have been well characterized, the intermediate structure(s) formed during the fusion reaction remains elusive. Genetic analysis would be expected to identify functional connections between intermediates. Since most membrane fusion systems are not genetically tractable, only few such

Frameshift Suppression in SACCHAROMYCES CEREVISIAE. V. Isolation and Genetic Properties of Nongroup-Specific Suppressors

PubMed Central

Culbertson, Michael R.; Gaber, Richard F.; Cummins, Claudia M.

1982-01-01

Two classes of frameshift suppressors distributed at 22 different loci were identified in previous studies in the yeast Saccharomyces cerevisiae. These suppressors exhibited allele-specific suppression of +1 G:C insertion mutations in either glycine or proline codons, designated as group II and group III frameshift mutations, respectively. Genes corresponding to representative suppressors of each group have been shown to encode altered glycine or proline tRNAs containing four base anticodons.—This communication reports the existence of a third class of frameshift suppressor that exhibits a wider range in specificity of suppression. The suppressors map at three loci, suf12, suf13, and suf14, which are located on chromosomes IV, XV, and XIV, respectively. The phenotypes of these suppressors suggest that suppression may be mediated by genes other than those encoding the primary structure of glycine or proline tRNAs. PMID:6757053

Tumor suppressor molecules and methods of use

DOEpatents

Welch, Peter J.; Barber, Jack R.

2004-09-07

The invention provides substantially pure tumor suppressor nucleic acid molecules and tumor suppressor polypeptides. The invention also provides hairpin ribozymes and antibodies selective for these tumor suppressor molecules. Also provided are methods of detecting a neoplastic cell in a sample using detectable agents specific for the tumor suppressor nucleic acids and polypeptides.

Germline PMS2 and somatic POLE exonuclease mutations cause hypermutability of the leading DNA strand in biallelic mismatch repair deficiency syndrome brain tumours.

PubMed

Andrianova, Maria A; Chetan, Ghati Kasturirangan; Sibin, Madathan Kandi; Mckee, Thomas; Merkler, Doron; Narasinga, Rao Kvl; Ribaux, Pascale; Blouin, Jean-Louis; Makrythanasis, Periklis; Seplyarskiy, Vladimir B; Antonarakis, Stylianos E; Nikolaev, Sergey I

2017-11-01

Biallelic mismatch repair deficiency (bMMRD) in tumours is frequently associated with somatic mutations in the exonuclease domains of DNA polymerases POLE or POLD1, and results in a characteristic mutational profile. In this article, we describe the genetic basis of ultramutated high-grade brain tumours in the context of bMMRD. We performed exome sequencing of two second-cousin patients from a large consanguineous family of Indian origin with early onset of high-grade glioblastoma and astrocytoma. We identified a germline homozygous nonsense variant, p.R802*, in the PMS2 gene. Additionally, by genome sequencing of these tumours, we found extremely high somatic mutation rates (237/Mb and 123/Mb), as well as somatic mutations in the proofreading domain of POLE polymerase (p.P436H and p.L424V), which replicates the leading DNA strand. Most interestingly, we found, in both cancers, that the vast majority of mutations were consistent with the signature of POLE exo - , i.e. an abundance of C>A and C>T mutations, particularly in special contexts, on the leading strand. We showed that the fraction of mutations under positive selection among mutations in tumour suppressor genes is more than two-fold lower in ultramutated tumours than in other glioblastomas. Genetic analyses enabled the diagnosis of the two consanguineous childhood brain tumours as being due to a combination of PMS2 germline and POLE somatic variants, and confirmed them as bMMRD/POLE exo - disorders. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

HIF1α and HIF2α: sibling rivalry in hypoxic tumour growth and progression.

PubMed

Keith, Brian; Johnson, Randall S; Simon, M Celeste

2011-12-15

Hypoxia-inducible factors (HIFs) are broadly expressed in human cancers, and HIF1α and HIF2α were previously suspected to promote tumour progression through largely overlapping functions. However, this relatively simple model has now been challenged in light of recent data from various approaches that reveal unique and sometimes opposing activities of these HIFα isoforms in both normal physiology and disease. These effects are mediated in part through the regulation of unique target genes, as well as through direct and indirect interactions with important oncoproteins and tumour suppressors, including MYC and p53. As HIF inhibitors are currently undergoing clinical evaluation as cancer therapeutics, a more thorough understanding of the unique roles performed by HIF1α and HIF2α in human neoplasia is warranted.

Adenoma-linked barrier defects and microbial products drive IL-23/IL-17-mediated tumour growth

PubMed Central

Grivennikov, Sergei I.; Wang, Kepeng; Mucida, Daniel; Stewart, C. Andrew; Schnabl, Bernd; Jauch, Dominik; Taniguchi, Koji; Yu, Guann-Yi; Osterreicher, Christoph H.; Hung, Kenneth E.; Datz, Christian; Feng, Ying; Fearon, Eric R.; Oukka, Mohamed; Tessarollo, Lino; Coppola, Vincenzo; Yarovinsky, Felix; Cheroutre, Hilde; Eckmann, Lars; Trinchieri, Giorgio; Karin, Michael

2013-01-01

Approximately 2% of colorectal cancer is linked to pre-existing inflammation known as colitis-associated cancer, but most develops in patients without underlying inflammatory bowel disease. Colorectal cancer often follows a genetic pathway whereby loss of the adenomatous polyposis coli (APC) tumour suppressor and activation of β-catenin are followed by mutations in K-Ras, PIK3CA and TP53, as the tumour emerges and progresses1,2. Curiously, however, ‘inflammatory signature’ genes characteristic of colitis-associated cancer are also upregulated in colorectal cancer3,4. Further, like most solid tumours, colorectal cancer exhibits immune/inflammatory infiltrates5, referred to as ‘tumour elicited inflammation’6. Although infiltrating CD4+ TH1 cells and CD8+ cytotoxic T cells constitute a positive prognostic sign in colorectal cancer7,8, myeloid cells and T-helper interleukin (IL)-17-producing (TH17) cells promote tumorigenesis5,6, and a ‘TH17 expression signature’ in stage I/II colorectal cancer is associated with a drastic decrease in disease-free survival9. Despite its pathogenic importance, the mechanisms responsible for the appearance of tumour-elicited inflammation are poorly understood. Many epithelial cancers develop proximally to microbial communities, which are physically separated from immune cells by an epithelial barrier10. We investigated mechanisms responsible for tumour-elicited inflammation in a mouse model of colorectal tumorigenesis, which, like human colorectal cancer, exhibits upregulation of IL-23 and IL-17. Here we show that IL-23 signalling promotes tumour growth and progression, and development of a tumoural IL-17 response. IL-23 is mainly produced by tumour-associated myeloid cells that are likely to be activated by microbial products, which penetrate the tumours but not adjacent tissue. Both early and late colorectal neoplasms exhibit defective expression of several barrier proteins. We propose that barrier deterioration induced by

Functional and molecular characterisation of EO771.LMB tumours, a new C57BL/6-mouse-derived model of spontaneously metastatic mammary cancer

PubMed Central

Johnstone, Cameron N.; Smith, Yvonne E.; Cao, Yuan; Burrows, Allan D.; Cross, Ryan S. N.; Ling, Xiawei; Redvers, Richard P.; Doherty, Judy P.; Eckhardt, Bedrich L.; Natoli, Anthony L.; Restall, Christina M.; Lucas, Erin; Pearson, Helen B.; Deb, Siddhartha; Britt, Kara L.; Rizzitelli, Alexandra; Li, Jason; Harmey, Judith H.; Pouliot, Normand; Anderson, Robin L.

2015-01-01

The translation of basic research into improved therapies for breast cancer patients requires relevant preclinical models that incorporate spontaneous metastasis. We have completed a functional and molecular characterisation of a new isogenic C57BL/6 mouse model of breast cancer metastasis, comparing and contrasting it with the established BALB/c 4T1 model. Metastatic EO771.LMB tumours were derived from poorly metastatic parental EO771 mammary tumours. Functional differences were evaluated using both in vitro assays and spontaneous metastasis assays in mice. Results were compared to non-metastatic 67NR and metastatic 4T1.2 tumours of the 4T1 model. Protein and transcript levels of markers of human breast cancer molecular subtypes were measured in the four tumour lines, as well as p53 (Tp53) tumour-suppressor gene status and responses to tamoxifen in vivo and in vitro. Array-based expression profiling of whole tumours identified genes and pathways that were deregulated in metastatic tumours. EO771.LMB cells metastasised spontaneously to lung in C57BL/6 mice and displayed increased invasive capacity compared with parental EO771. By immunohistochemical assessment, EO771 and EO771.LMB were basal-like, as was the 4T1.2 tumour, whereas 67NR had a luminal phenotype. Primary tumours from all lines were negative for progesterone receptor, Erb-b2/Neu and cytokeratin 5/6, but positive for epidermal growth factor receptor (EGFR). Only 67NR displayed nuclear estrogen receptor alpha (ERα) positivity. EO771 and EO771.LMB expressed mutant p53, whereas 67NR and 4T1.2 were p53-null. Integrated molecular analysis of both the EO771/EO771.LMB and 67NR/4T1.2 pairs indicated that upregulation of matrix metalloproteinase-3 (MMP-3), parathyroid hormone-like hormone (Pthlh) and S100 calcium binding protein A8 (S100a8) and downregulation of the thrombospondin receptor (Cd36) might be causally involved in metastatic dissemination of breast cancer. PMID:25633981

The tumour suppressor CDKN2A/p16INK4a regulates adipogenesis and bone marrow-dependent development of perivascular adipose tissue

PubMed Central

Wouters, Kristiaan; Deleye, Yann; Hannou, Sarah A; Vanhoutte, Jonathan; Maréchal, Xavier; Coisne, Augustin; Tagzirt, Madjid; Derudas, Bruno; Bouchaert, Emmanuel; Duhem, Christian; Vallez, Emmanuelle; Schalkwijk, Casper G; Pattou, François; Montaigne, David; Staels, Bart; Paumelle, Réjane

2017-01-01

The genomic CDKN2A/B locus, encoding p16INK4a among others, is linked to an increased risk for cardiovascular disease and type 2 diabetes. Obesity is a risk factor for both cardiovascular disease and type 2 diabetes. p16INK4a is a cell cycle regulator and tumour suppressor. Whether it plays a role in adipose tissue formation is unknown. p16INK4a knock-down in 3T3/L1 preadipocytes or p16INK4a deficiency in mouse embryonic fibroblasts enhanced adipogenesis, suggesting a role for p16INK4a in adipose tissue formation. p16INK4a-deficient mice developed more epicardial adipose tissue in response to the adipogenic peroxisome proliferator activated receptor gamma agonist rosiglitazone. Additionally, adipose tissue around the aorta from p16INK4a-deficient mice displayed enhanced rosiglitazone-induced gene expression of adipogenic markers and stem cell antigen, a marker of bone marrow-derived precursor cells. Mice transplanted with p16INK4a-deficient bone marrow had more epicardial adipose tissue compared to controls when fed a high-fat diet. In humans, p16INK4a gene expression was enriched in epicardial adipose tissue compared to other adipose tissue depots. Moreover, epicardial adipose tissue from obese humans displayed increased expression of stem cell antigen compared to lean controls, supporting a bone marrow origin of epicardial adipose tissue. These results show that p16INK4a modulates epicardial adipose tissue development, providing a potential mechanistic link between the genetic association of the CDKN2A/B locus and cardiovascular disease risk. PMID:28868898

[Hepatocellular tumours in noncirrhotic liver tissue].

PubMed

Goltz, D; Fischer, H-P

2015-11-01

In recent years, the spectrum of tissue-based diagnostics of hepatocellular tumours has changed due to novel molecular pathological findings. Innovative radiographics filter out small lesions and ambiguous tumours for bioptical sampling. The spectrum of these tumours includes hepatocellular carcinoma, hepatocellular adenomas, focal nodular hyperplasia and macroregenerative nodules. Primarily, morphological analysis should identify the dignity of a lesion. After exclusion of HCC and reactive liver cell nodules, hepatocellular adenomas should be further subclassified based on immunohistochemical/molecular pathological criteria according to the WHO classification of liver tumours. This procedure provides significant additional information regarding the prognosis and therapeutic implications of hepatocellular adenomas.

Suppression of tumour growth by orally administered osteopontin is accompanied by alterations in tumour blood vessels.

PubMed

Rittling, S R; Wejse, P L; Yagiz, K; Warot, G A; Hui, T

2014-03-04

The integrin-binding protein osteopontin is strongly associated with tumour development, yet is an abundant dietary component as a constituent of human and bovine milk. Therefore, we tested the effect of orally administered osteopontin (o-OPN) on the development of subcutaneous tumours in mice. Bovine milk osteopontin was administered in drinking water to tumour-bearing immune-competent mice. Tumour growth, proliferation, necrosis, apoptosis and blood vessel size and number were measured. Expression of the α₉ integrin was determined. o-OPN suppressed tumour growth, increased the extent of necrosis, and induced formation of abnormally large blood vessels. Anti-OPN reactivity detected in the plasma of OPN-null mice fed OPN suggested that tumour-blocking peptides were absorbed during digestion, but the o-OPN effect was likely distinct from that of an RGD peptide. Expression of the α₉ integrin was detected on both tumour cells and blood vessels. Potential active peptides from the α₉ binding site of OPN were identified by mass spectrometry following in vitro digestion, and injection of these peptides suppressed tumour growth. These results suggest that peptides derived from o-OPN are absorbed and interfere with tumour growth and normal vessel development. o-OPN-derived peptides that target the α₉ integrin are likely involved.

Remarkable stabilization of a psychrotrophic RNase HI by a combination of thermostabilizing mutations identified by the suppressor mutation method.

PubMed

Tadokoro, Takashi; Matsushita, Kyoko; Abe, Yumi; Rohman, Muhammad Saifur; Koga, Yuichi; Takano, Kazufumi; Kanaya, Shigenori

2008-08-05

Ribonuclease HI from the psychrotrophic bacterium Shewanella oneidensis MR-1 (So-RNase HI) is much less stable than Escherichia coli RNase HI (Ec-RNase HI) by 22.4 degrees C in T m and 12.5 kJ mol (-1) in Delta G(H 2O), despite their high degrees of structural and functional similarity. To examine whether the stability of So-RNase HI increases to a level similar to that of Ec-RNase HI via introduction of several mutations, the mutations that stabilize So-RNase HI were identified by the suppressor mutation method and combined. So-RNase HI and its variant with a C-terminal four-residue truncation (154-RNase HI) complemented the RNase H-dependent temperature-sensitive (ts) growth phenotype of E. coli strain MIC3001, while 153-RNase HI with a five-residue truncation could not. Analyses of the activity and stability of these truncated proteins suggest that 153-RNase HI is nonfunctional in vivo because of a great decrease in stability. Random mutagenesis of 153-RNase HI using error-prone PCR, followed by screening for the revertants, allowed us to identify six single suppressor mutations that make 153-RNase HI functional in vivo. Four of them markedly increased the stability of the wild-type protein by 3.6-6.7 degrees C in T m and 1.7-5.2 kJ mol (-1) in Delta G(H 2O). The effects of these mutations were nearly additive, and combination of these mutations increased protein stability by 18.7 degrees C in T m and 12.2 kJ mol (-1) in Delta G(H 2O). These results suggest that several residues are not optimal for the stability of So-RNase HI, and their replacement with other residues strikingly increases it to a level similar to that of the mesophilic counterpart.

SLAP displays tumour suppressor functions in colorectal cancer via destabilization of the SRC substrate EPHA2

NASA Astrophysics Data System (ADS)

Naudin, Cécile; Sirvent, Audrey; Leroy, Cédric; Larive, Romain; Simon, Valérie; Pannequin, Julie; Bourgaux, Jean-François; Pierre, Josiane; Robert, Bruno; Hollande, Frédéric; Roche, Serge

2014-01-01

The adaptor SLAP is a negative regulator of receptor signalling in immune cells but its role in human cancer is ill defined. Here we report that SLAP is abundantly expressed in healthy epithelial intestine but strongly downregulated in 50% of colorectal cancer. SLAP overexpression suppresses cell tumorigenicity and invasiveness while SLAP silencing enhances these transforming properties. Mechanistically, SLAP controls SRC/EPHA2/AKT signalling via destabilization of the SRC substrate and receptor tyrosine kinase EPHA2. This activity is independent from CBL but requires SLAP SH3 interaction with the ubiquitination factor UBE4A and SLAP SH2 interaction with pTyr594-EPHA2. SRC phosphorylates EPHA2 on Tyr594, thus creating a feedback loop that promotes EPHA2 destruction and thereby self-regulates its transforming potential. SLAP silencing enhances SRC oncogenicity and sensitizes colorectal tumour cells to SRC inhibitors. Collectively, these data establish a tumour-suppressive role for SLAP in colorectal cancer and a mechanism of SRC oncogenic induction through stabilization of its cognate substrates.

Is choline PET useful for identifying intraprostatic tumour lesions? A literature review.

PubMed

Chan, Joachim; Syndikus, Isabel; Mahmood, Shelan; Bell, Lynn; Vinjamuri, Sobhan

2015-09-01

More than 80% of patients with intermediate-risk or high-risk localized prostate cancer are cured with radiation doses of 74-78 Gy, but high doses increase the risk for late bowel and bladder toxicity among long-term survivors. Dose painting, defined as dose escalation to areas in the prostate containing the tumour, rather than to the whole gland, minimizes dose to normal tissues and hence toxicity. It requires accurate identification of the location and size of these lesions, for which functional MRI is the current gold standard. Many studies have assessed the use of choline PET in staging newly diagnosed patients. This review will discuss important imaging variables affecting the accuracy of choline PET scans, how choline PET contributes to tumour identification and is used in radiotherapy planning and how PET can improve the patient pathway involving prostate radiotherapy. In summary, the available literature shows that the accuracy of choline PET improves with higher tracer doses and delayed imaging (although the optimal uptake time is unclear), and tumour identification by MRI is improved by the addition of PET imaging. We propose future research with prolonged choline uptake time and multiphase imaging, which may further improve accuracy.

Down-regulation of the metastasis suppressor protein KAI1/CD82 correlates with occurrence of metastasis, prognosis and presence of HPV DNA in human penile squamous cell carcinoma.

PubMed

Protzel, C; Kakies, C; Kleist, B; Poetsch, M; Giebel, J

2008-04-01

In penile squamous cell carcinoma (PSCC), the outcome largely depends on early detection and resection of inguinal lymph node metastases. We investigated the role of metastasis suppressor protein kang ai 1 (KAI1)/cluster of differentiation 82 (CD82), which is known to be of prognostic significance for a wide variety of cancers. Moreover, we analysed the tumours for human papillomavirus (HPV) DNA and loss of heterozygosity at the 11p11.2 locus. Tissue samples of 30 primary PSCCs were investigated immunohistochemically using an anti-KAI1/CD82 polyclonal antibody. The expression was assessed according to the degree of KAI1/CD82-positive tumour cells as positive, decreased or negative. The presence of HPV6/11, HPV16 and HPV18 DNA was analysed by polymerase chain reaction. All patients with decreased or negative expression of KAI1/CD82 in primary lesions had lymph node metastases (p = 0.0002). Patients with positive KAI1/CD82 expression showed a significant better prognosis for survival compared to the other groups (p = 0.0042). Presence of HPV DNA was associated with decreased or negative KAI1/CD82 expression. Lacking or decreased expression of metastasis suppressor gene KAI1/CD82 appears to be a prognostic parameter for the occurrence of lymph node metastases in PSCC. Our study suggests an association of decreased KAI1/CD82 expression with tumour progression, development of metastases and disease-specific death.

miR-188-5p inhibits tumour growth and metastasis in prostate cancer by repressing LAPTM4B expression

PubMed Central

Zhang, Hongtuan; Qi, Shiyong; Zhang, Tao; Wang, Andi; Liu, Ranlu; Guo, Jia; Wang, Yuzhuo; Xu, Yong

2015-01-01

Elucidation of the molecular targets and pathways regulated by the tumour-suppressive miRNAs can shed light on the oncogenic and metastatic processes in prostate cancer (PCa). Using miRNA profiling analysis, we find that miR-188-5p was significantly down-regulated in metastatic PCa. Down-regulation of miR-188-5p is an independent prognostic factor for poor overall and biochemical recurrence-free survival. Restoration of miR-188-5p in PCa cells (PC-3 and LNCaP) significantly suppresses proliferation, migration and invasion in vitro and inhibits tumour growth and metastasis in vivo. We also find overexpression of miR-188-5p in PC-3 cells can significantly enhance the cells' chemosensitivity to adriamycin. LAPTM4B is subsequently identified as a direct target of miR-188-5p in PCa, and is found to be significantly over-expressed in PCa. Knockdown of LAPTM4B phenotypically copies miR-188-5p-induced phenotypes, whereas ectopic expression of LAPTM4B reverses the effects of miR-188-5p. We also find that restoration of miR-188-5p can inhibit the PI3K/AKT signaling pathway via the suppression of LAPTM4B. Taken together, this is the first report unveils that miR-188-5p acts as a tumour suppressor in PCa and may therefore serve as a useful therapeutic target for the development of new anticancer therapy. PMID:25714029

miR-188-5p inhibits tumour growth and metastasis in prostate cancer by repressing LAPTM4B expression.

PubMed

Zhang, Hongtuan; Qi, Shiyong; Zhang, Tao; Wang, Andi; Liu, Ranlu; Guo, Jia; Wang, Yuzhuo; Xu, Yong

2015-03-20

Elucidation of the molecular targets and pathways regulated by the tumour-suppressive miRNAs can shed light on the oncogenic and metastatic processes in prostate cancer (PCa). Using miRNA profiling analysis, we find that miR-188-5p was significantly down-regulated in metastatic PCa. Down-regulation of miR-188-5p is an independent prognostic factor for poor overall and biochemical recurrence-free survival. Restoration of miR-188-5p in PCa cells (PC-3 and LNCaP) significantly suppresses proliferation, migration and invasion in vitro and inhibits tumour growth and metastasis in vivo. We also find overexpression of miR-188-5p in PC-3 cells can significantly enhance the cells' chemosensitivity to adriamycin. LAPTM4B is subsequently identified as a direct target of miR-188-5p in PCa, and is found to be significantly over-expressed in PCa. Knockdown of LAPTM4B phenotypically copies miR-188-5p-induced phenotypes, whereas ectopic expression of LAPTM4B reverses the effects of miR-188-5p. We also find that restoration of miR-188-5p can inhibit the PI3K/AKT signaling pathway via the suppression of LAPTM4B. Taken together, this is the first report unveils that miR-188-5p acts as a tumour suppressor in PCa and may therefore serve as a useful therapeutic target for the development of new anticancer therapy.

Regulation of CTL responses to MHC-restricted class I peptide of the gp70 tumour antigen by splenic parenchymal CD4+ T cells in mice failing immunotherapy with DISC-mGM-CSF.

PubMed

Ahmad, Murrium; Rees, Robert C; McArdle, Stephanie E; Li, Geng; Mian, Shahid; Entwisle, Claire; Loudon, Peter; Ali, Selman A

2005-07-20

Direct intratumour injection of the disabled infectious single-cycle-herpes simplex virus-encoding murine granulocyte/macrophage colony-stimulating factor (DISC-HSV-mGM-CSF) into established colon carcinoma CT26 tumours induced complete tumour rejection in up to 70% of treated animals (regressors), while the remaining mice developed progressive tumours (progressors). This murine Balb/c model was used to dissect the cellular mechanisms involved in tumour regression or progression following immunotherapy. CTLs were generated by coculturing lymphocytes and parenchymal cells from the same spleens of individual regressor or progressor animals in the presence of the relevant AH-1 peptide derived from the gp70 tumour-associated antigens expressed by CT26 tumours. Tumour regression was correlated with potent CTL responses, spleen weight and cytokine (IFN-gamma) production. Conversely, progressor splenocytes exhibited weak to no CTL activity and poor IFN-gamma production, concomitant with the presence of a suppressor cell population in the progressor splenic parenchymal cell fraction. Further fractionation of this parenchymal subpopulation demonstrated that cells inhibitory to the activation of AH-1-specific CTLs, restimulated in vitro with peptide, were present in the nonadherent parenchymal fraction. In vitro depletion of progressor parenchymal CD3+/CD4+ T cells restored the CTL response of the cocultured splenocytes (regressor lymphocytes and progressor parenchymal cells) and decreased the production of IL-10, suggesting that CD3+CD4+ T lymphocytes present in the parenchymal fraction regulated the CTL response to AH-1. We examined the cellular responses associated with tumour rejection and progression, identifying regulatory pathways associated with failure to respond to immunotherapy. Copyright 2005 Wiley-Liss, Inc.

Mechanisms of regulation of cell-mediated immunity. III. The characterization of azobenzenearsonate-specific suppressor T-cell- derived-suppressor factors

PubMed Central

1979-01-01

Delayed type hypersensitivity to the hapten azobenzenearsonate (ABA) can be induced and suppressed by the administration of hapten-coupled syngeneic spleen cells by the appropriate route. Suppressor T cells stimulated by the intravenous administration of ABA-coupled spleen cells have been shown to produce a discrete subcellular factor(s) which is capable of suppressing delayed type hypersensitivity to azobenzenearsonate in the mouse. Such suppressor factors may be produced by the mechanical disruption of suppressor cells or by placing such suppressor cells in culture for 24 h. The suppressor factor(s) (SF) derived from ABA-specific suppressor cells exhibit biological specificity for the suppression of ABA delayed type hypersensitivity (DTH), but not trinitro-phenyl DTH, as well as the capacity to bind to ABA immunoadsorbents. Passage of suppressor factor(s) over reverse immunoadsorbents utilizing a rabbit anti-mouse F(ab')2 antiserum demonstrated that the antigen-specific T-cell derived SF does not bear conventional immunoglobulin markers. The suppressor factor(s) are not immunoglobulin molecules was further demonstrated by the inability of anti-ABA antibodies to suppress ABA DTH. Gel filtration of ABA suppressor factor(s) showed that the majority of the suppressive activity was present in a fraction with molecular weight ranging between 6.8 x 10(4) and 3.3 x 10(4) daltons. We also analyzed for the presence of determinants encoded by the H-2 major histocompatibility complex (MHC) and found that immunoadsorbents prepared utilizing antisera capable of interacting with gene products of the whole or selected gene regions of H-2 MHC, i.e., B10.D2 anti-B10.A and B10 anti- B10.A immunoadsorbents, retained the suppressive activity of ABA-SF. Elution of such columns with glycine HCl buffers (pH 2.8) permitted recovery of specific suppressive activity. Taken collectively such data supports the notion that suppressor T-cell-derived ABA suppressor factors have antigen

Frameshift Suppression in SACCHAROMYCES CEREVISIAE. III. Isolation and Genetic Properties of Group III Suppressors

PubMed Central

Cummins, Claudia M.; Gaber, Richard F.; Culbertson, Michael R.; Mann, Richard; Fink, Gerald R.

1980-01-01

Suppressors of ICR-induced mutations that exhibit behavior similar to bacterial frameshift suppressors have been identified in the yeast Saccharomyces cerevisiae. The yeast suppressors have been divided into two groups. Previous evidence indicated that suppressors of one group (Group II: SUF1, SUF3, SUF4, SUF5 and SUF6) represent mutations in the structural genes for glycyl-tRNA's. Suppressors of the other group (Group III: SUF2 and SUF7) were less well characterized. Although they suppressed some ICR-revertible mutations, they failed to suppress Group II frameshift mutations. This communication provides a more thorough characterization of the Group III suppressors and describes the isolation and properties of four new suppressors in that group (SUF8, SUF9, SUF10 and suf11).——In our original study, Group III suppressors were isolated as revertants of the Group III mutations his4–712 and his4–713. All suppressors obtained as ICR-induced revertants of these mutations mapped at the SUF2 locus near the centromere of chromosome III. Suppressors mapping at other loci were obtained in this study by analyzing spontaneous and UV-induced revertants of the Group III mutations. SUF2 and SUF10 suppress both Group III his4 mutations, whereas SUF7, SUF8, SUF9 and suf11 suppress his4–713, but not his4–712. All of the suppressors except suf11 are dominant in diploids homozygous for his4-713. The suppressors fail to suppress representative UAA, UAG and UGA nonsense mutations.——SUF9 is linked to the centromere of chromosome VI, and SUF10 is linked to the centromere of chromosome XIV. A triploid mapping procedure was used to determine the chromosome locations of SUF7 and SUF8. Subsequent standard crosses revealed linkage of SUF7 to cdc5 on chromosome XIII and linkage of SUF8 to cdc12 and pet3 on chromosome VIII. PMID:7009319

PLAU inferred from a correlation network is critical for suppressor function of regulatory T cells

PubMed Central

He, Feng; Chen, Hairong; Probst-Kepper, Michael; Geffers, Robert; Eifes, Serge; del Sol, Antonio; Schughart, Klaus; Zeng, An-Ping; Balling, Rudi

2012-01-01

Human FOXP3+CD25+CD4+ regulatory T cells (Tregs) are essential to the maintenance of immune homeostasis. Several genes are known to be important for murine Tregs, but for human Tregs the genes and underlying molecular networks controlling the suppressor function still largely remain unclear. Here, we describe a strategy to identify the key genes directly from an undirected correlation network which we reconstruct from a very high time-resolution (HTR) transcriptome during the activation of human Tregs/CD4+ T-effector cells. We show that a predicted top-ranked new key gene PLAU (the plasminogen activator urokinase) is important for the suppressor function of both human and murine Tregs. Further analysis unveils that PLAU is particularly important for memory Tregs and that PLAU mediates Treg suppressor function via STAT5 and ERK signaling pathways. Our study demonstrates the potential for identifying novel key genes for complex dynamic biological processes using a network strategy based on HTR data, and reveals a critical role for PLAU in Treg suppressor function. PMID:23169000

Integrative genomic analyses identify LIN28 and OLIG2 as markers of survival and metastatic potential in childhood central nervous system primitive neuro-ectodermal brain tumours

PubMed Central

Picard, Daniel; Miller, Suzanne; Hawkins, Cynthia E; Bouffet, Eric; Rogers, Hazel A; Chan, Tiffany SY; Kim, Seung-Ki; Ra, Young-Shin; Fangusaro, Jason; Korshunov, Andrey; Toledano, Helen; Nakamura, Hideo; Hayden, James T; Chan, Jennifer; Lafay-Cousin, Lucie; Hu, Ping X; Fan, Xing; Muraszko, Karin M; Pomeroy, Scott L; Lau, Ching C; Ng, Ho-Keung; Jones, Chris; Meter, Timothy Van; Clifford, Steven C; Eberhart, Charles; Gajjar, Amar; Pfister, Stefan M; Grundy, Richard G; Huang, Annie

2013-01-01

Background Childhood Central Nervous System Primitive Neuro-Ectodermal brain Tumours (CNS-PNETs) are highly aggressive brain tumours for which molecular features and best therapeutic strategy remains unknown. We interrogated a large cohort of these rare tumours in order to identify molecular markers that will enhance clinical management of CNS-PNET. Methods Transcriptional and copy number profiles from primary hemispheric CNS-PNETs were examined using clustering, gene and pathways enrichment analyses to discover tumour sub-groups and group-specific molecular markers. Immuno-histochemical and/or gene expression analyses were used to validate and examine the clinical significance of novel sub-group markers in 123 primary CNS-PNETs. Findings Three molecular sub-groups of CNS-PNETs distinguished by primitive neural (Group 1), oligo-neural (Group 2) and mesenchymal lineage (Group 3) gene expression signature were identified. Tumour sub-groups exhibited differential expression of cell lineage markers, LIN28 and OLIG2, and correlated with distinct demographics, survival and metastatic incidence. Group 1 tumours affected primarily younger females; male: female ratios were respectively 0.61 (median age 2.9 years; 95% CI: 2.4–5.2; p≤ 0.005), 1.25 (median age 7.9 years; 95% CI: 6–9.7) and 1.63 (median age 5.9 years; 95% CI: 4.9–7.8) for group 1, 2 and 3 patients. Overall outcome was poorest in group 1 patients which had a median survival of 0.8 years (95% CI: 0.47–1.2; p=0.019) as compared to 1.8 years (95% CI: 1.4–2.3) and 4.3 years; (95% CI: 0.82–7.8) respectively for group 2 and 3 patients. Group 3 tumours had the highest incidence of metastases at diagnosis; M0: M+ ratio were respectively 0.9 and 3.9 for group 3, versus group 1 and 2 tumours combined (p=0.037). Interpretation LIN28 and OLIG2 represent highly promising, novel diagnostic and prognostic molecular markers for CNS PNET that warrants further evaluation in prospective clinical trials. PMID:22691720

Tumour-derived alkaline phosphatase regulates tumour growth, epithelial plasticity and disease-free survival in metastatic prostate cancer

PubMed Central

Rao, S R; Snaith, A E; Marino, D; Cheng, X; Lwin, S T; Orriss, I R; Hamdy, F C; Edwards, C M

2017-01-01

Background: Recent evidence suggests that bone-related parameters are the main prognostic factors for overall survival in advanced prostate cancer (PCa), with elevated circulating levels of alkaline phosphatase (ALP) thought to reflect the dysregulated bone formation accompanying distant metastases. We have identified that PCa cells express ALPL, the gene that encodes for tissue nonspecific ALP, and hypothesised that tumour-derived ALPL may contribute to disease progression. Methods: Functional effects of ALPL inhibition were investigated in metastatic PCa cell lines. ALPL gene expression was analysed from published PCa data sets, and correlated with disease-free survival and metastasis. Results: ALPL expression was increased in PCa cells from metastatic sites. A reduction in tumour-derived ALPL expression or ALP activity increased cell death, mesenchymal-to-epithelial transition and reduced migration. Alkaline phosphatase activity was decreased by the EMT repressor Snail. In men with PCa, tumour-derived ALPL correlated with EMT markers, and high ALPL expression was associated with a significant reduction in disease-free survival. Conclusions: Our studies reveal the function of tumour-derived ALPL in regulating cell death and epithelial plasticity, and demonstrate a strong association between ALPL expression in PCa cells and metastasis or disease-free survival, thus identifying tumour-derived ALPL as a major contributor to the pathogenesis of PCa progression. PMID:28006818

Noise suppressor for turbo fan jet engines

NASA Technical Reports Server (NTRS)

Cheng, D. Y. (Inventor)

1983-01-01

A noise suppressor is disclosed for installation on the discharge or aft end of a turbo fan engine. Within the suppressor are fixed annular airfoils which are positioned to reduce the relative velocity between the high temperature fast moving jet exhaust and the low temperature slow moving air surrounding it. Within the suppressor nacelle is an exhaust jet nozzle which constrains the shape of the jet exhaust to a substantially uniform elongate shape irrespective of the power setting of the engine. Fixed ring airfoils within the suppressor nacelle therefore have the same salutary effects irrespective of the power setting at which the engine is operated.

Cooperative tumour cell membrane targeted phototherapy

NASA Astrophysics Data System (ADS)

Kim, Heegon; Lee, Junsung; Oh, Chanhee; Park, Ji-Ho

2017-06-01

The targeted delivery of therapeutics using antibodies or nanomaterials has improved the precision and safety of cancer therapy. However, the paucity and heterogeneity of identified molecular targets within tumours have resulted in poor and uneven distribution of targeted agents, thus compromising treatment outcomes. Here, we construct a cooperative targeting system in which synthetic and biological nanocomponents participate together in the tumour cell membrane-selective localization of synthetic receptor-lipid conjugates (SR-lipids) to amplify the subsequent targeting of therapeutics. The SR-lipids are first delivered selectively to tumour cell membranes in the perivascular region using fusogenic liposomes. By hitchhiking with extracellular vesicles secreted by the cells, the SR-lipids are transferred to neighbouring cells and further spread throughout the tumour tissues where the molecular targets are limited. We show that this tumour cell membrane-targeted delivery of SR-lipids leads to uniform distribution and enhanced phototherapeutic efficacy of the targeted photosensitizer.

Evaluating cell lines as tumour models by comparison of genomic profiles

PubMed Central

Domcke, Silvia; Sinha, Rileen; Levine, Douglas A.; Sander, Chris; Schultz, Nikolaus

2013-01-01

Cancer cell lines are frequently used as in vitro tumour models. Recent molecular profiles of hundreds of cell lines from The Cancer Cell Line Encyclopedia and thousands of tumour samples from the Cancer Genome Atlas now allow a systematic genomic comparison of cell lines and tumours. Here we analyse a panel of 47 ovarian cancer cell lines and identify those that have the highest genetic similarity to ovarian tumours. Our comparison of copy-number changes, mutations and mRNA expression profiles reveals pronounced differences in molecular profiles between commonly used ovarian cancer cell lines and high-grade serous ovarian cancer tumour samples. We identify several rarely used cell lines that more closely resemble cognate tumour profiles than commonly used cell lines, and we propose these lines as the most suitable models of ovarian cancer. Our results indicate that the gap between cell lines and tumours can be bridged by genomically informed choices of cell line models for all tumour types. PMID:23839242

Mutations in a signal sequence for the thylakoid membrane identify multiple protein transport pathways and nuclear suppressors

PubMed Central

1994-01-01

The apparatus that permits protein translocation across the internal thylakoid membranes of chloroplasts is completely unknown, even though these membranes have been the subject of extensive biochemical analysis. We have used a genetic approach to characterize the translocation of Chlamydomonas cytochrome f, a chloroplast-encoded protein that spans the thylakoid once. Mutations in the hydrophobic core of the cytochrome f signal sequence inhibit the accumulation of cytochrome f, lead to an accumulation of precursor, and impair the ability of Chlamydomonas cells to grow photosynthetically. One hydrophobic core mutant also reduces the accumulation of other thylakoid membrane proteins, but not those that translocate completely across the membrane. These results suggest that the signal sequence of cytochrome f is required and is involved in one of multiple insertion pathways. Suppressors of two signal peptide mutations describe at least two nuclear genes whose products likely describe the translocation apparatus, and selected second-site chloroplast suppressors further define regions of the cytochrome f signal peptide. PMID:8034740

Discovery of Tumor Suppressor Gene Function.

ERIC Educational Resources Information Center

Oppenheimer, Steven B.

1995-01-01

This is an update of a 1991 review on tumor suppressor genes written at a time when understanding of how the genes work was limited. A recent major breakthrough in the understanding of the function of tumor suppressor genes is discussed. (LZ)

Novel Drosophila Viruses Encode Host-Specific Suppressors of RNAi

PubMed Central

van Mierlo, Joël T.; Overheul, Gijs J.; Obadia, Benjamin; van Cleef, Koen W. R.; Webster, Claire L.; Saleh, Maria-Carla; Obbard, Darren J.; van Rij, Ronald P.

2014-01-01

The ongoing conflict between viruses and their hosts can drive the co-evolution between host immune genes and viral suppressors of immunity. It has been suggested that an evolutionary ‘arms race’ may occur between rapidly evolving components of the antiviral RNAi pathway of Drosophila and viral genes that antagonize it. We have recently shown that viral protein 1 (VP1) of Drosophila melanogaster Nora virus (DmelNV) suppresses Argonaute-2 (AGO2)-mediated target RNA cleavage (slicer activity) to antagonize antiviral RNAi. Here we show that viral AGO2 antagonists of divergent Nora-like viruses can have host specific activities. We have identified novel Nora-like viruses in wild-caught populations of D. immigrans (DimmNV) and D. subobscura (DsubNV) that are 36% and 26% divergent from DmelNV at the amino acid level. We show that DimmNV and DsubNV VP1 are unable to suppress RNAi in D. melanogaster S2 cells, whereas DmelNV VP1 potently suppresses RNAi in this host species. Moreover, we show that the RNAi suppressor activity of DimmNV VP1 is restricted to its natural host species, D. immigrans. Specifically, we find that DimmNV VP1 interacts with D. immigrans AGO2, but not with D. melanogaster AGO2, and that it suppresses slicer activity in embryo lysates from D. immigrans, but not in lysates from D. melanogaster. This species-specific interaction is reflected in the ability of DimmNV VP1 to enhance RNA production by a recombinant Sindbis virus in a host-specific manner. Our results emphasize the importance of analyzing viral RNAi suppressor activity in the relevant host species. We suggest that rapid co-evolution between RNA viruses and their hosts may result in host species-specific activities of RNAi suppressor proteins, and therefore that viral RNAi suppressors could be host-specificity factors. PMID:25032815

Review article: Pathogenesis and management of gastric carcinoid tumours.

PubMed

Burkitt, M D; Pritchard, D M

2006-11-01

Gastric carcinoid tumours are rare, but are increasing in incidence. To discuss tumour pathogenesis and outline current approaches to patient management. Review of published articles following a Pubmed search. Although interest in gastric carcinoids has increased since it was recognized that they are associated with achlorhydria, to date there is no definite evidence that humans taking long-term acid suppressing medication are at increased risk. Type I tumours are associated with autoimmune atrophic gastritis and hypergastrinaemia, type II are associated with Zollinger-Ellison syndrome, multiple endocrine neoplasia-1 and hypergastrinaemia and sporadic type III carcinoids are gastrin-independent and carry the worst prognosis. Careful investigation of these patients is required, particularly to identify the tumour type, the source of hypergastrinaemia and the presence of metastases. Treatment can be directed at the source of hypergastrinaemia if type I or II tumours are still gastrin responsive and not growing autonomously. Type III tumours should be treated surgically. Advances in our understanding of the pathogenesis of gastric carcinoids have led to recent improvements in investigation and management. Challenges remain in identifying the genetic and environmental factors, in addition to hypergastrinaemia, that are responsible for tumour development in susceptible patients.

An unusual characteristic "flower-like" pattern: flash suppressor burns.

PubMed

Gurcan, Altun

2012-04-01

The case on contact shots from firearms with a flash suppressor is rare. When a rifle fitted with a flash suppressor is fired, the emerging soot-laden gas in the barrel escapes from the slits of the flash suppressor. If the shot is contact or near contact, the flash suppressor will produce a characteristic "flower-like" pattern of seared, blackened zones around the entrance. This paper presents the injury pattern of the flash suppressor in a 29-year-old man who committed suicide with a G3 automatic infantry rifle.

[Neonatal tumours and congenital malformations].

PubMed

Berbel Tornero, O; Ortega García, J A; Ferrís i Tortajada, J; García Castell, J; Donat i Colomer, J; Soldin, O P; Fuster Soler, J L

2008-06-01

The association between pediatric cancer and congenital abnormalities is well known but, there is no exclusive data on the neonatal period and the underlying etiopathogenic mechanisms are unknown. First, to analyze the frequency of neonatal tumours associated with congenital abnormalities; and second, to comment on the likely etiopathogenic hypotheses of a relationship between neonatal tumours and congenital abnormalities. Historical series of neonatal tumours from La Fe University Children's Hospital in Valencia (Spain), from January 1990 to December 1999. Histological varieties of neonatal tumours and associated congenital abnormalities were described. A systematic review of the last 25 years was carried out using Medline, Cancerlit, Index Citation Science and Embase. The search profile used was the combination of "neonatal/congenital-tumors/cancer/neoplasms" and "congenital malformations/birth defects". 72 neonatal tumours were identified (2.8% of all pediatric cancers diagnosed in our hospital) and in 15 cases (20.8%) there was some associated malformation, disease or syndrome. The association between congenital abnormalities and neonatal tumours were: a) angiomas in three patients: two patients with congenital heart disease with a choanal stenosis, laryngomalacia; b) neuroblastomas in two patients: horseshoe kidney with vertebral anomalies and other with congenital heart disease; c) teratomas in two patients: one with cleft palate with vertebral anomalies and other with metatarsal varus; d) one tumour of the central nervous system with Bochdaleck hernia; e) heart tumours in four patients with tuberous sclerosis; f) acute leukaemia in one patient with Down syndrome and congenital heart disease; g) kidney tumour in one case with triventricular hydrocephaly, and h) adrenocortical tumour: hemihypertrophy. The publications included the tumours diagnosed in different pediatric periods and without unified criteria to classify the congenital abnormalities. Little data

Mimetics of Suppressor of cytokine signalling 3: novel potential therapeutics in triple breast cancer.

PubMed

La Manna, Sara; Lee, Eunmi; Ouzounova, Maria; Di Natale, Concetta; Novellino, Ettore; Merlino, Antonello; Korkaya, Hasan; Marasco, Daniela

2018-05-11

Suppressor of cytokine signaling (SOCS) family of proteins plays critical role in the regulation of immune responses controlling JAK/STAT mediated inflammatory cytokines. Among the members, SOCS1 and SOCS3 contain a kinase inhibitory region (KIR) and SOCS3 binds to JAK/STAT/gp130 complex by inhibiting the downstream signaling and suppressing inflammatory cytokines. Loss or reduced levels of SOCS3 have been linked to cancer-associated inflammation and suppressive immunity leading to enhanced tumour growth and metastasis. In line with these reports, we previously demonstrated that proteolytic degradation of SOCS3 in triple negative breast cancer (TNBC) subtype drives the expression of inflammatory cytokines. Therefore, we postulated that SOCS3 mimetics might suppress the inflammatory cytokine production in TNBC subtype and inhibit tumor growth and metastasis. Here we designed and characterized five linear peptides derived from the N-terminal region of SOCS3 encompassing regions that interface with the JAK2/gp130 complex by using the Circular Dichroism and Surface Plasmon Resonance spectroscopies. The KIRESS peptide resulted the sequence containing the most part of the hot-spots required for binding to JAK2 and was further investigated in vivo in mouse xenografts of MDA-MB-231-luci tumours as models of human TNBC subtype. Expectedly, this peptide showed a significant inhibition of primary tumour growth and pulmonary metastasis. Our studies suggest that SOCS3 peptidomimetics may possess a therapeutic potential in aggressive cancers, such as TNBC subtype, with activated inflammatory cytokines. This article is protected by copyright. All rights reserved. © 2018 UICC.

Biology of childhood germ cell tumours, focussing on the significance of microRNAs.

PubMed

Murray, M J; Nicholson, J C; Coleman, N

2015-01-01

Genomic and protein-coding transcriptomic data have suggested that germ cell tumours (GCTs) of childhood are biologically distinct from those of adulthood. Global messenger RNA profiles segregate malignant GCTs primarily by histology, but then also by age, with numerous transcripts showing age-related differential expression. Such differences are likely to account for the heterogeneous clinico-pathological behaviour of paediatric and adult malignant GCTs. In contrast, as global microRNA signatures of human tumours reflect their developmental lineage, we hypothesized that microRNA profiles would identify common biological abnormalities in all malignant GCTs owing to their presumed shared origin from primordial germ cells. MicroRNAs are short, non-protein-coding RNAs that regulate gene expression via translational repression and/or mRNA degradation. We showed that all malignant GCTs over-express the miR-371-373 and miR-302/367 clusters, regardless of patient age, histological subtype or anatomical tumour site. Furthermore, bioinformatic approaches and subsequent Gene Ontology analysis revealed that these two over-expressed microRNAs clusters co-ordinately down-regulated genes involved in biologically significant pathways in malignant GCTs. The translational potential of this finding has been demonstrated with the detection of elevated serum levels of miR-371-373 and miR-302/367 microRNAs at the time of malignant GCT diagnosis, with levels falling after treatment. The tumour-suppressor let-7 microRNA family has also been shown to be universally down-regulated in malignant GCTs, because of abundant expression of the regulatory gene LIN28. Low let-7 levels resulted in up-regulation of oncogenes including MYCN, AURKB and LIN28 itself, the latter through a direct feedback mechanism. Targeting LIN28, or restoring let-7 levels, both led to effective inhibition of this pathway. In summary, paediatric malignant GCTs show biological differences from their adult counterparts at

The Potential for Tumor Suppressor Gene Therapy in Head and Neck Cancer

PubMed Central

Birkeland, Andrew C.; Ludwig, Megan L.; Spector, Matthew E.; Brenner, J. Chad

2016-01-01

Head and neck squamous cell carcinoma remains a highly morbid and fatal disease. Importantly, genomic sequencing of head and neck cancers has identified frequent mutations in tumor suppressor genes. While targeted therapeutics increasingly are being investigated in head and neck cancer, the majority of these agents are against overactive/overexpressed oncogenes. Therapy to restore lost tumor suppressor gene function remains a key and under-addressed niche in trials for head and neck cancer. Recent advances in gene editing have captured the interest of both the scientific community and the public. As our technology for gene editing and gene expression modulation improves, addressing lost tumor suppressor gene function in head and neck cancers is becoming a reality. This review will summarize new techniques, challenges to implementation, future directions, and ethical ramifications of gene therapy in head and neck cancer. PMID:26896601

Gene transfer preferentially selects MHC class I positive tumour cells and enhances tumour immunogenicity.

PubMed

Hacker, Ulrich T; Schildhauer, Ines; Barroso, Margarita Céspedes; Kofler, David M; Gerner, Franz M; Mysliwietz, Josef; Buening, Hildegard; Hallek, Michael; King, Susan B S

2006-05-01

The modulated expression of MHC class I on tumour tissue is well documented. Although the effect of MHC class I expression on the tumorigenicity and immunogenicity of MHC class I negative tumour cell lines has been rigorously studied, less is known about the validity of gene transfer and selection in cell lines with a mixed MHC class I phenotype. To address this issue we identified a C26 cell subline that consists of distinct populations of MHC class I (H-2D/K) positive and negative cells. Transient transfection experiments using liposome-based transfer showed a lower transgene expression in MHC class I negative cells. In addition, MHC class I negative cells were more sensitive to antibiotic selection. This led to the generation of fully MHC class I positive cell lines. In contrast to C26 cells, all transfectants were rejected in vivo and induced protection against the parental tumour cells in rechallenge experiments. Tumour cell specificity of the immune response was demonstrated in in vitro cytokine secretion and cytotoxicity assays. Transfectants expressing CD40 ligand and hygromycin phosphotransferase were not more immunogenic than cells expressing hygromycin resistance alone. We suggest that the MHC class I positive phenotype of the C26 transfectants had a bearing on their immunogenicity, because selected MHC class I positive cells were more immunogenic than parental C26 cells and could induce specific anti-tumour immune responses. These data demonstrate that the generation of tumour cell transfectants can lead to the selection of subpopulations that show an altered phenotype compared to the parental cell line and display altered immunogenicity independent of selection marker genes or other immune modulatory genes. Our results show the importance of monitoring gene transfer in the whole tumour cell population, especially for the evaluation of in vivo therapies targeted to heterogeneous tumour cell populations.

The Promiscuous sumA Missense Suppressor from Salmonella enterica Has an Intriguing Mechanism of Action

PubMed Central

Cole, Ashley E.; Hani, Fatmah M.; Altman, Ronni; Meservy, Megan; Roth, John R.; Altman, Elliot

2017-01-01

While most missense suppressors have very narrow specificities and only suppress the allele against which they were isolated, the sumA missense suppressor from Salmonella enterica serovar Typhimurium is a promiscuous or broad-acting missense suppressor that suppresses numerous missense mutants. The sumA missense suppressor was identified as a glyV tRNA Gly3(GAU/C) missense suppressor that can recognize GAU or GAC aspartic acid codons and insert a glycine amino acid instead of aspartic acid. In addition to rescuing missense mutants caused by glycine to aspartic acid changes as expected, sumA could also rescue a number of other missense mutants as well by changing a neighboring (contacting) aspartic acid to glycine, which compensated for the other amino acid change. Thus the ability of sumA to rescue numerous missense mutants was due in part to the large number of glycine codons in genes that can be mutated to an aspartic acid codon and in part to the general tolerability and/or preference for glycine amino acids in proteins. Because the glyV tRNA Gly3(GAU/C) missense suppressor has also been extensively characterized in Escherichia coli as the mutA mutator, we demonstrated that all gain-of-function mutants isolated in a glyV tRNA Gly3(GAU/C) missense suppressor are transferable to a wild-type background and thus the increased mutation rates, which occur in glyV tRNA Gly3(GAU/C) missense suppressors, are not due to the suppression of these mutants. PMID:27974497

Consensus on the management of intracranial germ-cell tumours.

PubMed

Murray, Matthew J; Bartels, Ute; Nishikawa, Ryo; Fangusaro, Jason; Matsutani, Masao; Nicholson, James C

2015-09-01

The management of intracranial germ-cell tumours is complex because of varied clinical presentations, tumour sites, treatments and outcomes, and the need for multidisciplinary input. Participants of the 2013 Third International CNS Germ Cell Tumour Symposium (Cambridge, UK) agreed to undertake a multidisciplinary Delphi process to identify consensus in the clinical management of intracranial germ-cell tumours. 77 delegates from the symposium were selected as suitable experts in the field and were invited to participate in the Delphi survey, of which 64 (83%) responded to the invitation. Invited participants represented multiple disciplines from Asia, Australasia, Europe, and the Americas. 38 consensus statements encompassing aspects of intracranial germ-cell tumour work-up, staging, treatment, and follow-up were prepared. To achieve consensus, statements required at least 70% agreement from at least 60% of respondents. Overall, 34 (89%) of 38 statements met consensus criteria. This international Delphi approach has defined key areas of consensus that will help guide and streamline clinical management of patients with intracranial germ-cell tumours. Additionally, the Delphi approach identified areas of different understanding and clinical practice internationally in the management of these tumours, areas which should be the focus of future collaborative studies. Such efforts should translate into improved patient outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Coupled modelling of tumour angiogenesis, tumour growth and blood perfusion.

PubMed

Cai, Yan; Xu, Shixiong; Wu, Jie; Long, Quan

2011-06-21

We propose a mathematical modelling system to investigate the dynamic process of tumour cell proliferation, death and tumour angiogenesis by fully coupling the vessel growth, tumour growth and blood perfusion. Tumour growth and angiogenesis are coupled by the chemical microenvironment and the cell-matrix interaction. The haemodynamic calculation is carried out on the updated vasculature. The domains of intravascular, transcapillary and interstitial fluid flow were coupled in the model to provide a comprehensive solution of blood perfusion variables. An estimation of vessel collapse is made according to the wall shear stress criterion to provide feedback on vasculature remodelling. The simulation can show the process of tumour angiogenesis and the spatial distribution of tumour cells for periods of up to 24 days. It can show the major features of tumour and tumour microvasculature during the period such as the formation of a large necrotic core in the tumour centre with few functional vessels passing through, and a well circulated tumour periphery regions in which the microvascular density is high and associated with more aggressive proliferating cells of the growing tumour which are all consistent with physiological observations. The study also demonstrated that the simulation results are not dependent on the initial tumour and networks, which further confirms the application of the coupled model feedback mechanisms. The model enables us to examine the interactions between angiogenesis and tumour growth, and to study the dynamic response of a solid tumour to the changes in the microenvironment. This simulation framework can be a foundation for further applications such as drug delivery and anti-angiogenic therapies. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Monoallelic mutation analysis (MAMA) for identifying germline mutations.

PubMed

Papadopoulos, N; Leach, F S; Kinzler, K W; Vogelstein, B

1995-09-01

Dissection of germline mutations in a sensitive and specific manner presents a continuing challenge. In dominantly inherited diseases, mutations occur in only one allele and are often masked by the normal allele. Here we report the development of a sensitive and specific diagnostic strategy based on somatic cell hybridization termed MAMA (monoallelic mutation analysis). We have demonstrated the utility of this strategy in two different hereditary colorectal cancer syndromes, one caused by a defective tumour suppressor gene on chromosome 5 (familial adenomatous polyposis, FAP) and the other caused by a defective mismatch repair gene on chromosome 2 (hereditary non-polyposis colorectal cancer, HNPCC).

ABCE1 Is a Highly Conserved RNA Silencing Suppressor

PubMed Central

Kärblane, Kairi; Gerassimenko, Jelena; Nigul, Lenne; Piirsoo, Alla; Smialowska, Agata; Vinkel, Kadri; Kylsten, Per; Ekwall, Karl; Swoboda, Peter; Truve, Erkki; Sarmiento, Cecilia

2015-01-01

ATP-binding cassette sub-family E member 1 (ABCE1) is a highly conserved protein among eukaryotes and archaea. Recent studies have identified ABCE1 as a ribosome-recycling factor important for translation termination in mammalian cells, yeast and also archaea. Here we report another conserved function of ABCE1. We have previously described AtRLI2, the homolog of ABCE1 in the plant Arabidopsis thaliana, as an endogenous suppressor of RNA silencing. In this study we show that this function is conserved: human ABCE1 is able to suppress RNA silencing in Nicotiana benthamiana plants, in mammalian HEK293 cells and in the worm Caenorhabditis elegans. Using co-immunoprecipitation and mass spectrometry, we found a number of potential ABCE1-interacting proteins that might support its function as an endogenous suppressor of RNA interference. The interactor candidates are associated with epigenetic regulation, transcription, RNA processing and mRNA surveillance. In addition, one of the identified proteins is translin, which together with its binding partner TRAX supports RNA interference. PMID:25659154

Induction of suppressor cells in vitro by Candida albicans.

PubMed

Cuff, C F; Rogers, C M; Lamb, B J; Rogers, T J

1986-06-01

Normal splenocytes cultured with Formalin-killed Candida albicans were shown to acquire significant suppressor cell activity in a period of 3 days. These cells were found to suppress both the phytohemagglutinin-induced mitogen response as well as the anti-sheep erythrocyte antibody response. Experiments were carried out to determine the nature of the suppressor cell population. Results showed that these cells were not susceptible to treatment with anti-Thy 1 antibody and complement. Panning experiments showed that the suppressor cells were not plastic-adherent or Mac-1 antigen-positive. The suppressor cells were, however, adherent to anti-mouse immunoglobulin (F(ab')2-fragment)-coated dishes. Additional experiments showed that the suppressor cell activity was susceptible to treatment with monoclonal anti-Lyb 2.1 antibody and complement. These results suggest that the suppressor cell induced in vitro by Candida is a member of the B-lymphocyte lineage.

Tumour location within the breast: Does tumour site have prognostic ability?

PubMed

Rummel, Seth; Hueman, Matthew T; Costantino, Nick; Shriver, Craig D; Ellsworth, Rachel E

2015-01-01

Tumour location within the breast varies with the highest frequency in the upper outer quadrant (UOQ) and lowest frequency in the lower inner quadrant (LIQ). Whether tumour location is prognostic is unclear. To determine whether tumour location is prognostic, associations between tumour site and clinicopathological characteristics were evaluated. All patients enrolled in the Clinical Breast Care Project whose tumour site-UOQ, upper inner quadrant (UIQ), central, LIQ, lower outer quadrant (LOQ)-was determined by a single, dedicated breast pathologist were included in this study. Patients with multicentric disease (n = 122) or tumours spanning multiple quadrants (n = 381) were excluded from further analysis. Clinicopathological characteristics were analysed using chi-square tests for univariate analysis with multivariate analysis performed using principal components analysis (PCA) and multiple logistic regression. Significance was defined as P < 0.05. Of the 980 patients with defined tumour location, 30 had bilateral disease. Tumour location in the UOQ (51.5%) was significantly higher than in the UIQ (15.6%), LOQ (14.2%), central (10.6%), or LIQ (8.1%). Tumours in the central quadrant were significantly more likely to have higher tumour stage (P = 0.003) and size (P < 0.001), metastatic lymph nodes (P < 0.001), and mortality (P = 0.011). After multivariate analysis, only tumour size and lymph node status remained significantly associated with survival. Evaluation of tumour location as a prognostic factor revealed that although tumours in the central region are associated with less favourable outcome, these associations are not independent of location but rather driven by larger tumour size. Tumours in the central region are more difficult to detect mammographically, resulting in larger tumour size at diagnosis and thus less favourable prognosis. Together, these data demonstrate that tumour location is not an independent prognostic factor.

Off and back-on again: a tumor suppressor's tale.

PubMed

Acosta, Jonuelle; Wang, Walter; Feldser, David M

2018-06-01

Tumor suppressor genes play critical roles orchestrating anti-cancer programs that are both context dependent and mechanistically diverse. Beyond canonical tumor suppressive programs that control cell division, cell death, and genome stability, unexpected tumor suppressor gene activities that regulate metabolism, immune surveillance, the epigenetic landscape, and others have recently emerged. This diversity underscores the important roles these genes play in maintaining cellular homeostasis to suppress cancer initiation and progression, but also highlights a tremendous challenge in discerning precise context-specific programs of tumor suppression controlled by a given tumor suppressor. Fortunately, the rapid sophistication of genetically engineered mouse models of cancer has begun to shed light on these context-dependent tumor suppressor activities. By using techniques that not only toggle "off" tumor suppressor genes in nascent tumors, but also facilitate the timely restoration of gene function "back-on again" in disease specific contexts, precise mechanisms of tumor suppression can be revealed in an unbiased manner. This review discusses the development and implementation of genetic systems designed to toggle tumor suppressor genes off and back-on again and their potential to uncover the tumor suppressor's tale.

An unusual characteristic “flower-like” pattern: flash suppressor burns

PubMed Central

Gurcan, Altun

2012-01-01

The case on contact shots from firearms with a flash suppressor is rare. When a rifle fitted with a flash suppressor is fired, the emerging soot-laden gas in the barrel escapes from the slits of the flash suppressor. If the shot is contact or near contact, the flash suppressor will produce a characteristic “flower-like” pattern of seared, blackened zones around the entrance. This paper presents the injury pattern of the flash suppressor in a 29-year-old man who committed suicide with a G3 automatic infantry rifle. PMID:23935280

Ring structure amino acids affect the suppressor activity of melon aphid-borne yellows virus P0 protein.

PubMed

Han, Yan-Hong; Xiang, Hai-Ying; Wang, Qian; Li, Yuan-Yuan; Wu, Wen-Qi; Han, Cheng-Gui; Li, Da-Wei; Yu, Jia-Lin

2010-10-10

Melon aphid-borne yellows virus (MABYV) is a newly identified polerovirus occurring in China. Here, we demonstrate that the MABYV encoded P0 (P0(MA)) protein is a strong suppressor of post-transcriptional gene silencing (PTGS) with activity comparable to tobacco etch virus (TEV) HC-Pro. In addition we have shown that the LP F-box motif present at the N-terminus of P0(MA) is required for suppressor activity. Detailed mutational analyses on P0(MA) revealed that changing the conserved Trp 212 with non-ring structured amino acids altered silencing suppressor functions. Ala substitutions at positions 12 and 211 for Phe had no effect on P0 suppression-activity, whereas Arg and Glu substitutions had greatly decreased suppressor activity. Furthermore, substitutions targeting Phe at position 30 also resulted in reduced P0 suppression-activity. Altogether, these results suggest that ring structured Trp/Phe residues in P0 have important roles in suppressor activity. Copyright © 2010 Elsevier Inc. All rights reserved.

Evidence for label-retaining tumour-initiating cells in human glioblastoma

PubMed Central

Deleyrolle, Loic P.; Harding, Angus; Cato, Kathleen; Siebzehnrubl, Florian A.; Rahman, Maryam; Azari, Hassan; Olson, Sarah; Gabrielli, Brian; Osborne, Geoffrey; Vescovi, Angelo

2011-01-01

Individual tumour cells display diverse functional behaviours in terms of proliferation rate, cell–cell interactions, metastatic potential and sensitivity to therapy. Moreover, sequencing studies have demonstrated surprising levels of genetic diversity between individual patient tumours of the same type. Tumour heterogeneity presents a significant therapeutic challenge as diverse cell types within a tumour can respond differently to therapies, and inter-patient heterogeneity may prevent the development of general treatments for cancer. One strategy that may help overcome tumour heterogeneity is the identification of tumour sub-populations that drive specific disease pathologies for the development of therapies targeting these clinically relevant sub-populations. Here, we have identified a dye-retaining brain tumour population that displays all the hallmarks of a tumour-initiating sub-population. Using a limiting dilution transplantation assay in immunocompromised mice, label-retaining brain tumour cells display elevated tumour-initiation properties relative to the bulk population. Importantly, tumours generated from these label-retaining cells exhibit all the pathological features of the primary disease. Together, these findings confirm dye-retaining brain tumour cells exhibit tumour-initiation ability and are therefore viable targets for the development of therapeutics targeting this sub-population. PMID:21515906

Tumour cell dispersion by the ultrasonic aspirator during brain tumour resection.

PubMed

Preston, J K; Masciopinto, J; Salamat, M S; Badie, B

1999-10-01

Ultrasonic aspirators are commonly used to resect brain tumours because they allow safe, rapid and accurate removal of diseased tissue. Since ultrasonic aspirators generate a spray of aerosolized irrigating fluid around the instrument tip, we questioned whether this spray might contain viable tumours cells that could contribute to intraoperative spread of tumour fragments. To test this hypothesis, we collected the spray produced during the resection of nine brain tumours with an ultrasonic aspirator and semi-quantitatively analysed it for tumour presence. The aerosolized irrigation fluid was found to contain intact tumour cells or clumps of tumour cells in all nine instances, and there was a trend of increasing tumour cell dispersion with increasing ultrasonic aspiration times. Further examination is required to determine if this intraoperative dispersion of apparently viable tumour fragments contributes to local neoplasm recurrence.

Breast cancer tumour growth modelling for studying the association of body size with tumour growth rate and symptomatic detection using case-control data.

PubMed

Abrahamsson, Linda; Czene, Kamila; Hall, Per; Humphreys, Keith

2015-08-21

A large body size is associated with larger breast cancer tumours at diagnosis. Standard regression models for tumour size at diagnosis are not sufficient for unravelling the mechanisms behind the association. Using Swedish case-control data, we identified 1352 postmenopausal women with incident invasive breast cancer diagnosed between 1993 and 1995. We used a novel continuous tumour growth model, which models tumour sizes at diagnosis through three submodels: for tumour growth, time to symptomatic detection, and screening sensitivity. Tumour size at other time points is thought of as a latent variable. We quantified the relationship between body size with tumour growth and time to symptomatic detection. High body mass index and large breast size are, respectively, significantly associated with fast tumour growth rate and delayed time to symptomatic detection (combined P value = 5.0 × 10(-5) and individual P values = 0.089 and 0.022). We also quantified the role of mammographic density in screening sensitivity. The times at which tumours will be symptomatically detected may vary substantially between women with different breast sizes. The proposed tumour growth model represents a novel and useful approach for quantifying the effects of breast cancer risk factors on tumour growth and detection.

Remarkable difference of somatic mutation patterns between oncogenes and tumor suppressor genes.

PubMed

Liu, Haoxuan; Xing, Yuhang; Yang, Sihai; Tian, Dacheng

2011-12-01

Cancers arise owing to mutations that confer selective growth advantages on the cells in a subset of tumor suppressor and/or oncogenes. To understand oncogenesis and diagnose cancers, it is crucial to discriminate these two groups of genes by using the difference in their mutation patterns. Here, we investigated>120,000 mutation samples in 66 well-known tumor suppressor genes and oncogenes of the COSMIC database, and found a set of significant differences in mutation patterns (e.g., non-3n-indel, non-sense SNP and mutation hotspot) between them. By screening the best measurement, we developed indices to readily distinguish one from another and predict clearly the unknown oncogenesis genes as tumor suppressors (e.g., ASXL1, HNF1A and KDM6A) or oncogenes (e.g., FOXL2, MYD88 and TSHR). Based on our results, a third gene group can be classified, which has a mutational pattern between tumor suppressors and oncogenes. The concept of the third gene group could help to understand gene function in different cancers or individual patients and to know the exact function of genes in oncogenesis. In conclusion, our study provides further insights into cancer-related genes and identifies several potential therapeutic targets.

The Succinated Proteome of FH-Mutant Tumours

PubMed Central

Yang, Ming; Ternette, Nicola; Su, Huizhong; Dabiri, Raliat; Kessler, Benedikt M.; Adam, Julie; Teh, Bin Tean; Pollard, Patrick J.

2014-01-01

Inherited mutations in the Krebs cycle enzyme fumarate hydratase (FH) predispose to hereditary leiomyomatosis and renal cell cancer (HLRCC). Loss of FH activity in HLRCC tumours causes accumulation of the Krebs cycle intermediate fumarate to high levels, which may act as an oncometabolite through various, but not necessarily mutually exclusive, mechanisms. One such mechanism, succination, is an irreversible non-enzymatic modification of cysteine residues by fumarate, to form S-(2-succino)cysteine (2SC). Previous studies have demonstrated that succination of proteins including glyceraldehyde 3-phosphate dehydrogenase (GAPDH), kelch-like ECH-associated protein 1 (KEAP1) and mitochondrial aconitase (ACO2) can have profound effects on cellular metabolism. Furthermore, immunostaining for 2SC is a sensitive and specific biomarker for HLRCC tumours. Here, we performed a proteomic screen on an FH-mutant tumour and two HLRCC-derived cancer cell lines and identified 60 proteins where one or more cysteine residues were succinated; 10 of which were succinated at cysteine residues either predicted, or experimentally proven, to be functionally significant. Bioinformatic enrichment analyses identified most succinated targets to be involved in redox signaling. To our knowledge, this is the first proteomic-based succination screen performed in human tumours and cancer-derived cells and has identified novel 2SC targets that may be relevant to the pathogenesis of HLRCC. PMID:25105836

Lymphocytic response to tumour and deficient DNA mismatch repair identify subtypes of stage II/III colorectal cancer associated with patient outcomes.

PubMed

Williams, David S; Mouradov, Dmitri; Jorissen, Robert N; Newman, Marsali R; Amini, Elham; Nickless, David K; Teague, Julie A; Fang, Catherine G; Palmieri, Michelle; Parsons, Marie J; Sakthianandeswaren, Anuratha; Li, Shan; Ward, Robyn L; Hawkins, Nicholas J; Faragher, Ian; Jones, Ian T; Gibbs, Peter; Sieber, Oliver M

2018-01-30

Tumour-infiltrating lymphocyte (TIL) response and deficient DNA mismatch repair (dMMR) are determinants of prognosis in colorectal cancer. Although highly correlated, evidence suggests that these are independent predictors of outcome. However, the prognostic significance of combined TIL/MMR classification and how this compares to the major genomic and transcriptomic subtypes remain unclear. A prospective cohort of 1265 patients with stage II/III cancer was examined for TIL/MMR status and BRAF / KRAS mutations. Consensus molecular subtype (CMS) status was determined for 142 cases. Associations with 5-year disease-free survival (DFS) were evaluated and validated in an independent cohort of 602 patients. Tumours were categorised into four subtypes based on TIL and MMR status: TIL-low/proficient-MMR (pMMR) (61.3% of cases), TIL-high/pMMR (14.8%), TIL-low/dMMR (8.6%) and TIL-high/dMMR (15.2%). Compared with TIL-high/dMMR tumours with the most favourable prognosis, both TIL-low/dMMR (HR=3.53; 95% CI=1.88 to 6.64; P multivariate <0.001) and TIL-low/pMMR tumours (HR=2.67; 95% CI=1.47 to 4.84; P multivariate =0.001) showed poor DFS. Outcomes of patients with TIL-low/dMMR and TIL-low/pMMR tumours were similar. TIL-high/pMMR tumours showed intermediate survival rates. These findings were validated in an independent cohort. TIL/MMR status was a more significant predictor of prognosis than National Comprehensive Cancer Network high-risk features and was a superior predictor of prognosis compared with genomic (dMMR, pMMR/ BRAF wt / KRAS wt , pMMR/ BRAF mut / KRAS wt , pMMR/ BRAF wt / KRAS mut ) and transcriptomic (CMS 1-4) subtypes. TIL/MMR classification identified subtypes of stage II/III colorectal cancer associated with different outcomes. Although dMMR status is generally considered a marker of good prognosis, we found this to be dependent on the presence of TILs. Prognostication based on TIL/MMR subtypes was superior compared with histopathological, genomic and

Site-specific volumetric analysis of lung tumour motion

NASA Astrophysics Data System (ADS)

Pepin, Eric W.; Wu, Huanmei; Sandison, George A.; Langer, Mark; Shirato, Hiroki

2010-06-01

The treatment of lung cancer with radiation therapy is hindered by respiratory motion. Real-time adjustments to compensate for this motion are hampered by mechanical system latencies and imaging-rate restrictions. To better understand tumour motion behaviour for adaptive image-guided radiation therapy of lung cancer, the volume of a tumour's motion space was investigated. Motion data were collected by tracking an implanted fiducial using fluoroscopy at 30 Hz during treatment sessions. A total of 637 treatment fractions from 31 tumours were used in this study. For each fraction, data points collected from three consecutive breathing cycles were used to identify instantaneous tumour location. A convex hull was created over these data points, defining the tumour motion envelope. The study sought a correlation between the tumour location in the lung and the convex hull's volume and shape. It was found that tumours located in the upper apex had smaller motion envelopes (<50 mm3), whereas tumours located near the chest wall or diaphragm had larger envelopes (>70 mm3). Tumours attached to fixed anatomical structures had small motion spaces. Three general shapes described the tumour motion envelopes: 50% of motion envelopes enclosed largely 1D oscillation, 38% enclosed an ellipsoid path, 6% enclosed an arced path and 6% were of hybrid shape. This location-space correlation suggests it may be useful in developing a predictive model, but more work needs to be done to verify it.

Two Replicable Suppressor Situations in Personality Research

ERIC Educational Resources Information Center

Paulhus, Delroy L.; Robins, Richard W.; Trzesniewski, Kali H.; Tracy, Jessica L.

2004-01-01

Suppressor situations occur when the simultaneous inclusion of two predictors improves one or both validities. A common allegation is that suppressor effects rarely replicate and have little substantive import. We present substantive examples from two established research domains to counter this skepticism. In the first domain, we show how…

Gastric tumours in FAP.

PubMed

Walton, Sarah-Jane; Frayling, Ian M; Clark, Susan K; Latchford, Andrew

2017-07-01

Gastric cancer is not a recognised extra-colonic manifestation of FAP, except in countries with a high prevalence of gastric cancer. Data regarding gastric adenomas in FAP are sparse. The aim of this study was to review the clinical characteristics of gastric tumours occurring within an FAP population from the largest European polyposis registry. All patients that developed a gastric adenoma or carcinoma were identified from a prospectively maintained registry database. The primary outcome measure was the occurrence of gastric adenoma or adenocarcinoma. Secondary outcomes included APC mutation, tumour stage, management and survival. Eight patients developed gastric cancer and 21 an adenoma (median age 52 and 44 years, respectively). Regular oesophagogastroduodenoscopy surveillance was performed in 6/8 patients who developed cancer. Half were advanced T3/4 tumours and 6/8 had nodal or metastatic spread at diagnosis. All cancer cases died within a median of 13.5 months from diagnosis. Gastric adenomas were evenly distributed: 11/21 (52%) in the distal and 10/21 (48%) proximal stomach, whereas 5/8 (63%) cancers were located proximally. An association between gastric tumour and desmoid development was observed; 7/8 (88%) cancer and 11/21 (52%) adenoma cases had a personal or family history of desmoid. It would appear from this small, retrospective study that gastric cancer is not a prominent extra-colonic feature of FAP in the Western world. It seems to present at an advanced stage with a poor prognosis. There may be an association between gastric tumour and desmoid occurrence but a large multicentre cohort is necessary to investigate this further.

Anti-tumour strategies aiming to target tumour-associated macrophages

PubMed Central

Tang, Xiaoqiang; Mo, Chunfen; Wang, Yongsheng; Wei, Dandan; Xiao, Hengyi

2013-01-01

Tumour-associated macrophages (TAMs) represent a predominant population of inflammatory cells that present in solid tumours. TAMs are mostly characterized as alternatively activated M2-like macrophages and are known to orchestrate nearly all stages of tumour progression. Experimental investigations indicate that TAMs contribute to drug-resistance and radio-protective effects, and clinical evidence shows that an elevated number of TAMs and their M2 profile are correlated with therapy failure and poor prognosis in cancer patients. Recently, many studies on TAM-targeted strategies have made significant progress and some pilot works have achieved encouraging results. Among these, connections between some anti-tumour drugs and their influence on TAMs have been suggested. In this review, we will summarize recent advances in TAM-targeted strategies for tumour therapy. Based on the proposed mechanisms, those strategies are grouped into four categories: (i) inhibiting macrophage recruitment; (ii) suppressing TAM survival; (iii) enhancing M1-like tumoricidal activity of TAMs; (iv) blocking M2-like tumour-promoting activity of TAMs. It is desired that further attention be drawn to this research field and more effort be made to promote TAM-targeted tumour therapy. PMID:23113570

Transcriptome and proteome analysis of tyrosine kinase inhibitor treated canine mast cell tumour cells identifies potentially kit signaling-dependent genes

PubMed Central

2012-01-01

Background Canine mast cell tumour proliferation depends to a large extent on the activity of KIT, a tyrosine kinase receptor. Inhibitors of the KIT tyrosine kinase have recently been introduced and successfully applied as a therapeutic agent for this tumour type. However, little is known on the downstream target genes of this signaling pathway and molecular changes after inhibition. Results Transcriptome analysis of the canine mast cell tumour cell line C2 treated for up to 72 hours with the tyrosine kinase inhibitor masitinib identified significant changes in the expression levels of approximately 3500 genes or 16% of the canine genome. Approximately 40% of these genes had increased mRNA expression levels including genes associated with the pro-proliferative pathways of B- and T-cell receptors, chemokine receptors, steroid hormone receptors and EPO-, RAS and MAP kinase signaling. Proteome analysis of C2 cells treated for 72 hours identified 24 proteins with changed expression levels, most of which being involved in gene transcription, e.g. EIA3, EIA4, TARDBP, protein folding, e.g. HSP90, UCHL3, PDIA3 and protection from oxidative stress, GSTT3, SELENBP1. Conclusions Transcriptome and proteome analysis of neoplastic canine mast cells treated with masitinib confirmed the strong important and complex role of KIT in these cells. Approximately 16% of the total canine genome and thus the majority of the active genes were significantly transcriptionally regulated. Most of these changes were associated with reduced proliferation and metabolism of treated cells. Interestingly, several pro-proliferative pathways were up-regulated, which may represent attempts of masitinib treated cells to activate alternative pro-proliferative pathways. These pathways may contain hypothetical targets for a combination therapy with masitinib to further improve its therapeutic effect. PMID:22747577

Measurand transient signal suppressor

NASA Technical Reports Server (NTRS)

Bozeman, Richard J., Jr. (Inventor)

1994-01-01

A transient signal suppressor for use in a controls system which is adapted to respond to a change in a physical parameter whenever it crosses a predetermined threshold value in a selected direction of increasing or decreasing values with respect to the threshold value and is sustained for a selected discrete time interval is presented. The suppressor includes a sensor transducer for sensing the physical parameter and generating an electrical input signal whenever the sensed physical parameter crosses the threshold level in the selected direction. A manually operated switch is provided for adapting the suppressor to produce an output drive signal whenever the physical parameter crosses the threshold value in the selected direction of increasing or decreasing values. A time delay circuit is selectively adjustable for suppressing the transducer input signal for a preselected one of a plurality of available discrete suppression time and producing an output signal only if the input signal is sustained for a time greater than the selected suppression time. An electronic gate is coupled to receive the transducer input signal and the timer output signal and produce an output drive signal for energizing a control relay whenever the transducer input is a non-transient signal which is sustained beyond the selected time interval.

Suppressor Effects of Coping Strategies on Resilience

ERIC Educational Resources Information Center

Yoon, Jae ho; Lee, Ji hae; Lee, Chae Yeon; Cho, Minhee; Lee, Sang Min

2014-01-01

The purpose of the current study is to demonstrate a significant suppressor effect among coping strategies on resilience. Two different samples were used to replicate the suppressor effect. Participants in the first example were 391 adolescents (middle school students) in Korea, and participants in the second example were 282 young adults…

Mediastinal germ cell tumour causing superior vena cava tumour thrombosis.

PubMed

Karanth, Suman S; Vaid, Ashok K; Batra, Sandeep; Sharma, Devender

2015-03-25

We report a rare case of a 35-year-old man who presented with a 1-week history of retrosternal chest pain of moderate intensity. A positron emission tomography CT (PET-CT) showed a large fluorodeoxy-glucose (FDG)-avid heterogeneously enhancing necrotic mass in the anterosuperior mediastinum with a focal FDG-avid thrombosis of the superior vena cava (SVC) suggestive of tumour thrombus and vascular invasion. α-Fetoprotein levels were raised (5690 IU/L). Image guided biopsy of the mediastinal mass was suggestive of non-seminomatous germ cell tumour (NSGCT). The patient received four cycles of BEP (bleomycin, etoposide and cisplatin) along with therapeutic anticoagulation with low-molecular-weight heparin. Follow-up whole body PET-CT revealed complete resolution of mediastinal mass and SVC tumour thrombosis. The documentation of FDG-PET-avid tumour thrombus resolving with chemotherapy supports the concept of circulating tumour cells being important not only in common solid tumours such as breast and colon cancer but also in relatively less common tumours such as NSGCT. The detection of circulating tumour cells could help deploy aggressive regimens upfront. 2015 BMJ Publishing Group Ltd.

The epidemiology of neonatal tumours. Report of an international working group.

PubMed

Moore, S W; Satgé, D; Sasco, A J; Zimmermann, A; Plaschkes, J

2003-09-01

Neonatal tumours occur every 12,500-27,500 live births and comprise 2% of childhood malignancies, but there is little clarity as to their real prevalence, sites of origin and pathological nature as reported series vary. As an entity, neonatal tumours provide a unique window of opportunity to study tumours in which minimal environmental interference has occurred. The majority of tumours present with a mass at birth (e.g., teratomas, neuroblastomas, mesoblastic nephroma, fibromatosis), which are not infrequently identified on antenatal ultrasound. Histologically, teratoma and neuroblastoma remain the two main tumour types encountered with soft tissue sarcoma, renal tumours, CNS tumours and leukaemia being the next most common tumour types identified. Malignant tumours are uncommon in the neonatal period per se and benign tumours may have malignant potential. A particular problem exists in clinical classification, as histological features of malignancy do not always correlate with clinical behaviour. Benign tumours may also be life threatening because of their size and location. Other tumours may demonstrate local invasiveness, but no metastatic potential, and tumours that are clearly malignant may demonstrate unpredictable or uncertain behaviour. Screening programmes have brought more tumours to light, but do not appear to affect the overall prognosis. They may provide clues to the stage at which tumours develop in foetu. The aetiology of cancer in children is multifactorial and includes both genetic and environmental factors. The association between congenital abnormalities and tumours is well established (15% of neonatal tumours). Genetic defects are highly likely in neonatal tumours and include those with a high risk of malignancy (e.g., retinoblastoma), but also genetically determined syndromes with an increased risk of malignancy and complex genetic rearrangements. Tumours are mostly genetically related at a cellular level and factors influencing cellular

K-Ras(V14I) -induced Noonan syndrome predisposes to tumour development in mice.

PubMed

Hernández-Porras, Isabel; Schuhmacher, Alberto J; Garcia-Medina, Raquel; Jiménez, Beatriz; Cañamero, Marta; de Martino, Alba; Guerra, Carmen

2016-06-01

The Noonan syndrome (NS) is an autosomal dominant genetic disorder characterized by short stature, craniofacial dysmorphism, and congenital heart defects. A significant proportion of NS patients may also develop myeloproliferative disorders (MPDs), including juvenile myelomonocytic leukaemia (JMML). Surprisingly, scarce information is available in relation to other tumour types in these patients. We have previously developed and characterized a knock-in mouse model that carries one of the most frequent KRAS-NS-related mutations, the K-Ras(V14I) substitution, which recapitulates most of the alterations described in NS patients, including MPDs. The K-Ras(V14I) mutation is a mild activating K-Ras protein; thus, we have used this model to study tumour susceptibility in comparison with mice expressing the classical K-Ras(G12V) oncogene. Interestingly, our studies have shown that these mice display a generalized tumour predisposition and not just MPDs. In fact, we have observed that the K-Ras(V14I) mutation is capable of cooperating with the p16Ink4a/p19Arf and Trp53 tumour suppressors, as well as with other risk factors such as pancreatitis, thereby leading to a higher cancer incidence. In conclusion, our results illustrate that the K-Ras(V14I) activating protein is able to induce cancer, although at a much lower level than the classical K-Ras(G12V) oncogene, and that it can be significantly modulated by both genetic and non-genetic events. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Tumor suppressor C-RASSF proteins.

PubMed

Iwasa, Hiroaki; Hossain, Shakhawoat; Hata, Yutaka

2018-05-01

Human genome has ten genes that are collectedly called Ras association domain family (RASSF). RASSF is composed of two subclasses, C-RASSF and N-RASSF. Both N-RASSF and C-RASSF encode Ras association domain-containing proteins and are frequently suppressed by DNA hypermethylation in human cancers. However, C-RASSF and N-RASSF are quite different. Six C-RASSF proteins (RASSF1-6) are characterized by a C-terminal coiled-coil motif named Salvador/RASSF/Hippo domain, while four N-RASSF proteins (RASSF7-10) lack it. C-RASSF proteins interact with mammalian Ste20-like kinases-the core kinases of the tumor suppressor Hippo pathway-and cross-talk with this pathway. Some of them share the same interacting molecules such as MDM2 and exert the tumor suppressor role in similar manners. Nevertheless, each C-RASSF protein has distinct characters. In this review, we summarize our current knowledge of how C-RASSF proteins play tumor suppressor roles and discuss the similarities and differences among C-RASSF proteins.

Separation of concanavalin A-induced human suppressor and helper T cells by the autologous erythrocyte rosette technique.

PubMed

Sakane, T; Honda, M; Taniguchi, Y; Kotani, H

1981-08-01

Very few normal human peripheral blood T cells are capable of binding autologous erythrocytes to form rosettes, whereas in the T cell population activated by concanavalin A (Con A) the autorosette levels are markedly enhanced. Fractionation of the Con A-activated T cells with autologous erythrocytes into autorosetting and nonrosetting cells demonstrates that suppressor, but not helper, activity resides in the autorosetting population, whereas the reverse is true of the nonrosetting population. Both these activities are found to be Con A dependent. The Con A-induced human suppressor cells can be identified and separated from the Con A-induced human helper cells by the autorosette technique. Studies on the surface properties of autorosetting and nonrosetting T cells indicate that there is little correlation between the activated suppressor and helper T cell subsets defined by autorosette technique and either those defined by monoclonal antibodies (which are able to distinguish these subsets in the resting but not activated T cells) or those defined by Fc receptors. Since the autorosetting T cell population (which acts as suppressor cells) bears receptors for peanut agglutinin, the nature of Con A-induced human suppressor cells appears to be analogous to that of Con A-induced murine suppressor cells.

Effects of a suppressor tone on distortion product otoacoustic emissions fine structure: why a universal suppressor level is not a practical solution to obtaining single-generator DP-grams.

PubMed

Dhar, Sumitrajit; Shaffer, Lauren A

2004-12-01

The use of a suppressor tone has been proposed as the method of choice in obtaining single-generator distortion product (DP) grams, the speculation being that such DP grams will be more predictive of hearing thresholds. Current distortion product otoacoustic emissions (DPOAE) theory points to the ear canal DPOAE signal being a complex interaction between multiple components. The effectiveness of a suppressor tone is predicted to be dependent entirely on the relative levels of these components. We examine the validity of using a suppressor tone through a detailed examination of the effects of a suppressor on DPOAE fine structure in individual ears. DPOAE fine structure, recorded in 10 normal-hearing individuals with a suppressor tone at 45, 55, and 65 dB SPL, was compared with recordings without a suppressor. Behavioral hearing thresholds were also measured in the same subjects, using 2-dB steps. The effect of the suppressor tone on DPOAE fine structure varied between ears and was dependent on frequency within ears. Correlation between hearing thresholds and DPOAE level measured without a suppressor was similar to previous reports. The effects of the suppressor are explained in the theoretical framework of a model involving multiple DPOAE components. Our results suggest that a suppressor tone can have highly variable effects on fine structure across individuals or even across frequency within one ear, thereby making the use of a suppressor less viable as a clinical tool for obtaining single-generator DP grams.

MEK inhibition prevents tumour-shed transforming growth factor-β-induced T-regulatory cell augmentation in tumour milieu.

PubMed

Hossain, Dewan M S; Panda, Abir K; Chakrabarty, Sreeparna; Bhattacharjee, Pushpak; Kajal, Kirti; Mohanty, Suchismita; Sarkar, Irene; Sarkar, Diptendra K; Kar, Santosh K; Sa, Gaurisankar

2015-04-01

Tumour progression is associated with immune-suppressive conditions that facilitate the escape of tumour cells from the regimen of immune cells, subsequently paralysing the host defence mechanisms. Induction of CD4(+)  CD25(+)  FoxP3(+) T regulatory (Treg) cells has been implicated in the tumour immune escape mechanism, although the novel anti-cancer treatment strategies targeting Treg cells remain unknown. The focus of this study is to define the interaction between tumour and immune system, i.e. how immune tolerance starts and gradually leads to the induction of adaptive Treg cells in the tumour microenvironment. Our study identified hyperactivated mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) -signalling as a potential target for reversing Treg cell augmentation in breast cancer patients. In more mechanistic detail, pharmacological inhibitors of MEK/ERK signalling inhibited transforming growth factor-β (TGF-β) production in tumour cells that essentially blocked TGF-β-SMAD3/SMAD4-mediated induction of CD25/interleukin-2 receptor α on CD4(+) T-cell surface. As a result high-affinity binding of interleukin-2 on those cells was prohibited, causing lack of Janus kinase 1 (JAK1)/JAK3-mediated signal transducer and activator of transcription 3 (STAT3)/STAT5 activation required for FoxP3 expression. Finally, for a more radical approach towards a safe MEK inhibitor, we validate the potential of multi-kinase inhibitor curcumin, especially the nano-curcumin made out of pure curcumin with greater bioavailability; in repealing tumour-shed TGF-β-induced Treg cell augmentation. © 2014 Bose Institute.

MEK inhibition prevents tumour-shed transforming growth factor-β-induced T-regulatory cell augmentation in tumour milieu

PubMed Central

Hossain, Dewan M S; Panda, Abir K; Chakrabarty, Sreeparna; Bhattacharjee, Pushpak; Kajal, Kirti; Mohanty, Suchismita; Sarkar, Irene; Sarkar, Diptendra K; Kar, Santosh K; Sa, Gaurisankar

2015-01-01

Tumour progression is associated with immune-suppressive conditions that facilitate the escape of tumour cells from the regimen of immune cells, subsequently paralysing the host defence mechanisms. Induction of CD4+ CD25+ FoxP3+ T regulatory (Treg) cells has been implicated in the tumour immune escape mechanism, although the novel anti-cancer treatment strategies targeting Treg cells remain unknown. The focus of this study is to define the interaction between tumour and immune system, i.e. how immune tolerance starts and gradually leads to the induction of adaptive Treg cells in the tumour microenvironment. Our study identified hyperactivated mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) -signalling as a potential target for reversing Treg cell augmentation in breast cancer patients. In more mechanistic detail, pharmacological inhibitors of MEK/ERK signalling inhibited transforming growth factor-β (TGF-β) production in tumour cells that essentially blocked TGF-β-SMAD3/SMAD4-mediated induction of CD25/interleukin-2 receptor α on CD4+ T-cell surface. As a result high-affinity binding of interleukin-2 on those cells was prohibited, causing lack of Janus kinase 1 (JAK1)/JAK3-mediated signal transducer and activator of transcription 3 (STAT3)/STAT5 activation required for FoxP3 expression. Finally, for a more radical approach towards a safe MEK inhibitor, we validate the potential of multi-kinase inhibitor curcumin, especially the nano-curcumin made out of pure curcumin with greater bioavailability; in repealing tumour-shed TGF-β-induced Treg cell augmentation. PMID:25284464

Single-cell mRNA profiling reveals transcriptional heterogeneity among pancreatic circulating tumour cells.

PubMed

Lapin, Morten; Tjensvoll, Kjersti; Oltedal, Satu; Javle, Milind; Smaaland, Rune; Gilje, Bjørnar; Nordgård, Oddmund

2017-05-31

Single-cell mRNA profiling of circulating tumour cells may contribute to a better understanding of the biology of these cells and their role in the metastatic process. In addition, such analyses may reveal new knowledge about the mechanisms underlying chemotherapy resistance and tumour progression in patients with cancer. Single circulating tumour cells were isolated from patients with locally advanced or metastatic pancreatic cancer with immuno-magnetic depletion and immuno-fluorescence microscopy. mRNA expression was analysed with single-cell multiplex RT-qPCR. Hierarchical clustering and principal component analysis were performed to identify expression patterns. Circulating tumour cells were detected in 33 of 56 (59%) examined blood samples. Single-cell mRNA profiling of intact isolated circulating tumour cells revealed both epithelial-like and mesenchymal-like subpopulations, which were distinct from leucocytes. The profiled circulating tumour cells also expressed elevated levels of stem cell markers, and the extracellular matrix protein, SPARC. The expression of SPARC might correspond to an epithelial-mesenchymal transition in pancreatic circulating tumour cells. The analysis of single pancreatic circulating tumour cells identified distinct subpopulations and revealed elevated expression of transcripts relevant to the dissemination of circulating tumour cells to distant organ sites.

Utility of Phox2b immunohistochemical stain in neural crest tumours and non-neural crest tumours in paediatric patients.

PubMed

Warren, Mikako; Matsuno, Ryosuke; Tran, Henry; Shimada, Hiroyuki

2018-03-01

This study evaluated the utility of Phox2b in paediatric tumours. Previously, tyrosine hydroxylase (TH) was the most widely utilised sympathoadrenal marker specific for neural crest tumours with neuronal/neuroendocrine differentiation. However, its sensitivity is insufficient. Recently Phox2b has emerged as another specific marker for this entity. Phox2b immunohistochemistry (IHC) was performed on 159 paediatric tumours, including (group 1) 65 neural crest tumours with neuronal differentiation [peripheral neuroblastic tumours (pNT)]: 15 neuroblastoma undifferentiated (NB-UD), 10 NB poorly differentiated (NB-PD), 10 NB differentiating (NB-D), 10 ganglioneuroblastoma intermixed (GNBi), 10 GNB nodular (GNBn) and 10 ganglioneuroma (GN); (group 2) 23 neural crest tumours with neuroendocrine differentiation [pheochromocytoma/paraganglioma (PCC/PG)]; (group 3) 27 other neural crest tumours including one composite rhabdomyosarcoma/neuroblastoma; and (group 4) 44 non-neural crest tumours. TH IHC was performed on groups 1, 2 and 3. Phox2b was expressed diffusely in pNT (n = 65 of 65), strongly in NB-UD and NB-PD and with less intensity in NB-D, GNB and GN. Diffuse TH was seen in all NB-PD, NB-D, GNB and GN, but nine of 15 NB-UD and a nodule in GNBn did not express TH (n = 55 of 65). PCC/PG expressed diffuse Phox2b (n = 23 of 23) and diffuse TH, except for one tumour (n = 22 of 23). In composite rhabdomyosarcoma, TH was expressed only in neuroblastic cells and Phox2b was diffusely positive in neuroblastic cells and focally in rhabdomyosarcoma. All other tumours were negative for Phox2b (n = none of 44). Phox2b was a specific and sensitive marker for pNT and PCC/PG, especially useful for identifying NB-UD often lacking TH. Our study also presented a composite rhabdomyosarcoma/neuroblastoma of neural crest origin. © 2017 John Wiley & Sons Ltd.

Analysis of gene expression as relevant to cancer cells and circulating tumour cells.

PubMed

Friel, Anne M; Crown, John; O'Driscoll, Lorraine

2011-01-01

Current literature provides significant evidence to support the concept that there are limited subpopulations of cells within a solid tumour that have increased tumour-initiating potential relative to the total tumour population. Such tumour-initiating cells have been identified in leukaemia and in a variety of solid tumours using different combinations of cell surface markers, suggesting that a tumour-initiating cell heterogeneity exists for each specific tumour. These studies have been extended to endometrial cancer; and herein we present several experimental approaches, both in vitro and in vivo, that can be used to determine whether such populations exist, and if so, to characterize them. These methods are adaptable to the investigation of tumour-initiating cells from other tumour types.

Suppressors of dGTP Starvation in Escherichia coli

PubMed Central

Itsko, Mark

2017-01-01

. coli cells continued cell growth but eventually developed a DNA replication defect, leading to cell death due to formation of unresolvable DNA structures. Nevertheless, dGTP-starved cultures eventually resumed growth due to the appearance of resistant mutants. Here, we used whole-genome DNA sequencing to identify the responsible suppressor mutations. We show that the majority of suppressors can circumvent death by upregulating purine de novo biosynthesis, leading to restoration of dGTP to acceptable levels. PMID:28373271

Canine perineal tumours.

PubMed

Berrocal, A; Vos, J H; van den Ingh, T S; Molenbeek, R F; van Sluijs, F J

1989-12-01

One hundred and thirty nine canine perineal tumours were histologically evaluated. The vast majority (134 tumours = 96.4%) appeared to originate from the characteristic glandular structures of this region. They were classified as well differentiated perianal gland tumours (58.3%), as moderately or poorly differentiated perianal gland tumours (21.6%) and as carcinomas without perianal gland differentiation (16.5%). Only 5 tumours (3.6%) appeared to originate from non-characteristic perineal structures. A prominent male predominance was found with respect to the perianal gland tumours, whereas the carcinomas showed a distinct female predisposition. Tumours showing perianal gland differentiation almost invariably will have a benign behaviour. The carcinomas lacking any perianal gland differentiation often show a distinct malignant behaviour with metastases to regional lymph nodes and internal organs. These malignant neoplasms showed morphological and clinical features comparable to canine anal sac gland adenocarcinomas and carcinoids in man and animals.

Identification of new adventitious rooting mutants amongst suppressors of the Arabidopsis thaliana superroot2 mutation.

PubMed

Pacurar, Daniel Ioan; Pacurar, Monica Lacramioara; Bussell, John Desmond; Schwambach, Joseli; Pop, Tiberia Ioana; Kowalczyk, Mariusz; Gutierrez, Laurent; Cavel, Emilie; Chaabouni, Salma; Ljung, Karin; Fett-Neto, Arthur Germano; Pamfil, Doru; Bellini, Catherine

2014-04-01

The plant hormone auxin plays a central role in adventitious rooting and is routinely used with many economically important, vegetatively propagated plant species to promote adventitious root initiation and development on cuttings. Nevertheless the molecular mechanisms through which it acts are only starting to emerge. The Arabidopsis superroot2-1 (sur2-1) mutant overproduces auxin and, as a consequence, develops excessive adventitious roots in the hypocotyl. In order to increase the knowledge of adventitious rooting and of auxin signalling pathways and crosstalk, this study performed a screen for suppressors of superroot2-1 phenotype. These suppressors provide a new resource for discovery of genetic players involved in auxin signalling pathways or at the crosstalk of auxin and other hormones or environmental signals. This study reports the identification and characterization of 26 sur2-1 suppressor mutants, several of which were identified as mutations in candidate genes involved in either auxin biosynthesis or signalling. In addition to confirming the role of auxin as a central regulator of adventitious rooting, superroot2 suppressors indicated possible crosstalk with ethylene signalling in this process.

Low tumour cell content in a lung tumour bank: implications for molecular characterisation.

PubMed

Goh, Felicia; Duhig, Edwina E; Clarke, Belinda E; McCaul, Elizabeth; Passmore, Linda; Courtney, Deborah; Windsor, Morgan; Naidoo, Rishendren; Franz, Louise; Parsonson, Kylie; Yang, Ian A; Bowman, Rayleen V; Fong, Kwun M

2017-10-01

Lung cancer encompasses multiple malignant epithelial tumour types, each with specific targetable, potentially actionable mutations, such that precision management mandates accurate tumour typing. Molecular characterisation studies require high tumour cell content and low necrosis content, yet lung cancers are frequently a heterogeneous mixture of tumour and stromal cells. We hypothesised that there may be systematic differences in tumour cell content according to histological subtype, and that this may have implications for tumour banks as a resource for comprehensive molecular characterisation studies in lung cancer. To investigate this, we estimated tumour cell and necrosis content of 4267 samples resected from 752 primary lung tumour specimens contributed to a lung tissue bank. We found that banked lung cancer samples had low tumour cell content (33%) generally, although it was higher in carcinoids (77.5%) than other lung cancer subtypes. Tumour cells comprise a variable and often small component of banked resected tumour samples, and are accompanied by stromal reaction, inflammation, fibrosis, and normal structures. This has implications for the adequacy of unselected tumour bank samples for diagnostic and molecular investigations, and further research is needed to determine whether tumour cell content has a significant impact on analytical results in studies using tissue from tumour bank resources. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Circulating Cell-Free Tumour DNA in the Management of Cancer

PubMed Central

Francis, Glenn; Stein, Sandra

2015-01-01

With the development of new sensitive molecular techniques, circulating cell-free tumour DNA containing mutations can be identified in the plasma of cancer patients. The applications of this technology may result in significant changes to the care and management of cancer patients. Whilst, currently, these “liquid biopsies” are used to supplement the histological diagnosis of cancer and metastatic disease, in the future these assays may replace the need for invasive procedures. Applications include the monitoring of tumour burden, the monitoring of minimal residual disease, monitoring of tumour heterogeneity, monitoring of molecular resistance and early diagnosis of tumours and metastatic disease. PMID:26101870

Induction of human antigen-specific suppressor factors in vitro.

PubMed Central

Kontiainen, S; Woody, J N; Rees, A; Feldmann, M

1981-01-01

Based on methods used for the in vitro induction of antigen-specific suppressor cells in the mouse, we have cultured Ficoll-Isopaque-separated human blood cells with high dose of antigen (100 microgram/ml) in Marbrook culture vessels for 4 days. The resulting cells, when further recultured for 24 hr with a low dose of antigen (1 microgram/ml), released into the supernatant material, termed 'suppressor factor', which inhibited, in an antigen-specific manner, the antibody response of mouse spleen cells in culture. The suppressor factor was analysed using immunoabsorbents, and was bound to and eluted from specific antigen, concanavalin A and lentil lectin, anti-human Ia antibodies, and anti-mouse suppressor factor antibodies, but was not bound to antibodies against human IgG. PMID:6169475

Messenger RNA (mRNA) nanoparticle tumour vaccination

NASA Astrophysics Data System (ADS)

Phua, Kyle K. L.; Nair, Smita K.; Leong, Kam W.

2014-06-01

Use of mRNA-based vaccines for tumour immunotherapy has gained increasing attention in recent years. A growing number of studies applying nanomedicine concepts to mRNA tumour vaccination show that the mRNA delivered in nanoparticle format can generate a more robust immune response. Advances in the past decade have deepened our understanding of gene delivery barriers, mRNA's biological stability and immunological properties, and support the notion for engineering innovations tailored towards a more efficient mRNA nanoparticle vaccine delivery system. In this review we will first examine the suitability of mRNA for engineering manipulations, followed by discussion of a model framework that highlights the barriers to a robust anti-tumour immunity mediated by mRNA encapsulated in nanoparticles. Finally, by consolidating existing literature on mRNA nanoparticle tumour vaccination within the context of this framework, we aim to identify bottlenecks that can be addressed by future nanoengineering research.

A study of the transmission characteristics of suppressor nozzles

NASA Technical Reports Server (NTRS)

Ahuja, K. K.; Salikuddin, M.; Burrin, R. H.; Plumbee, H. E., Jr.

1980-01-01

The internal noise radiation characteristics for a single stream 12 lobe 24 tube suppressor nozzle, and for a dual stream 36 chute suppressor nozzle were investigated. An equivalent single round conical nozzle and an equivalent coannular nozzle system were also tested to provide a reference for the two suppressors. The technique utilized a high voltage spark discharge as a noise source within the test duct which permitted separation of the incident, reflected and transmitted signals in the time domain. These signals were then Fourier transformed to obtain the nozzle transmission coefficient and the power transfer function. These transmission parameters for the 12 lobe, 24 tube suppressor nozzle and the reference conical nozzle are presented as a function of jet Mach number, duct Mach number polar angle and temperature. Effects of simulated forward flight are also considered for this nozzle. For the dual stream, 36 chute suppressor, the transmission parameters are presented as a function of velocity ratios and temperature ratios. Possible data for the equivalent coaxial nozzle is also presented. Jet noise suppression by these nozzles is also discussed.

Microenvironmental autophagy promotes tumour growth.

PubMed

Katheder, Nadja S; Khezri, Rojyar; O'Farrell, Fergal; Schultz, Sebastian W; Jain, Ashish; Rahman, Mohammed M; Schink, Kay O; Theodossiou, Theodossis A; Johansen, Terje; Juhász, Gábor; Bilder, David; Brech, Andreas; Stenmark, Harald; Rusten, Tor Erik

2017-01-19

As malignant tumours develop, they interact intimately with their microenvironment and can activate autophagy, a catabolic process which provides nutrients during starvation. How tumours regulate autophagy in vivo and whether autophagy affects tumour growth is controversial. Here we demonstrate, using a well characterized Drosophila melanogaster malignant tumour model, that non-cell-autonomous autophagy is induced both in the tumour microenvironment and systemically in distant tissues. Tumour growth can be pharmacologically restrained using autophagy inhibitors, and early-stage tumour growth and invasion are genetically dependent on autophagy within the local tumour microenvironment. Induction of autophagy is mediated by Drosophila tumour necrosis factor and interleukin-6-like signalling from metabolically stressed tumour cells, whereas tumour growth depends on active amino acid transport. We show that dormant growth-impaired tumours from autophagy-deficient animals reactivate tumorous growth when transplanted into autophagy-proficient hosts. We conclude that transformed cells engage surrounding normal cells as active and essential microenvironmental contributors to early tumour growth through nutrient-generating autophagy.

Primary intrapulmonary solitary fibrous tumours

PubMed Central

Lin, Xia; Xiang, Yingming; Shi, Hongcan; Zhang, Fangbiao

2018-01-01

Due to the extreme rarity of primary intrapulmonary solitary fibrous tumours (SFTs), their clinical course, imaging characteristics, diagnosis, treatment and prognosis are poorly understood. The present study therefore assessed the diagnosis and management of primary intrapulmonary SFTs and systematically reviewed previously reported cases in the literature. A total of 5 patients who underwent resection for primary intrapulmonary SFTs were enrolled in the present study and their clinical course, tumour characteristics, management and survival were assessed in this retrospective study. Relevant studies regarding primary intrapulmonary SFTs were searched using PubMed and tumour characteristics, clinicopathologic features, therapeutic strategy and survival outcomes were reviewed. Of the 5 cases, all were males, with a mean age of 57.6 years (range, 37–68 years). All patients were asymptomatic and were identified incidentally on routine computed tomography examination. A total of 3 patients underwent thoracotomy and 2 patients underwent video-assisted thoracoscopic surgery. All tumours were completely resected. Postoperative haemorrhage occurred in 1 patient and he received surgical intervention for haemostasis. The average hospital stay was 15 (4–22) days, and no mortality occurred. The mean length of the postoperative follow-up was 37.6 (1–67) months. One patient was lost to follow-up, and 4 patients were asymptomatic. A total of 19 studies were identified from database searches. They included a total of 45 patients: Twenty-three males and 22 females (mean age, 59.4 years; range, 7–81 years). A total of 12 patients were asymptomatic, and pain and coughing were the major symptoms. Five, one, two, four, and 17 tumours occurred in the right upper lobe, right middle lobe, right lower lobe, left upper lobe and left lower lobe, respectively. A total of 39 patients underwent surgery, 1 patient underwent radiotherapy, and 1 patient underwent radiofrequency ablation

[Application of PLA Method for Detection of p53/p63/p73 Complexes in Situ in Tumour Cells and Tumour Tissue].

PubMed

Hrabal, V; Nekulová, M; Nenutil, R; Holčaková, J; Coates, P J; Vojtěšek, B

2017-01-01

PLA (proximity ligation assay) can be used for detection of protein-protein interactions in situ directly in cells and tissues. Due to its high sensitivity and specificity it is useful for detection, localization and quantification of protein complexes with single molecule resolution. One of the mechanisms of mutated p53 gain of function is formation of proten-protein complexes with other members of p53 family - p63 and p73. These interactions influences chemosensitivity and invasivity of cancer cells and this is why these complexes are potential targets of anti-cancer therapy. The aim of this work is to detect p53/p63/p73 interactions in situ in tumour cells and tumour tissue using PLA method. Unique in-house antibodies for specific detection of p63 and p73 isoforms were developed and characterized. Potein complexes were detected using PLA in established cell lines SVK14, HCC1806 and FaDu and in paraffin sections of colorectal carcinoma tissue. Cell lines were also processed to paraffin blocks. p53/T-antigen and ΔNp63/T-antigen protein complexes were detected in SVK14 cells using PLA. Interactions of ΔNp63 and TAp73 isoforms were found in HCC1806 cell line with endogenous expression of these proteins. In FaDu cell line mut-p53/TAp73 complex was localized but not mut-p53/ΔNp63 complex. p53 tetramer was detected directly in colorectal cancer tissue. During development of PLA method for detection of protein complexes between p53 family members we detected interactions of p53 and p63 with T-antigen and mut-p53 and ΔNp63 with TAp73 tumour suppressor in tumour cell lines and p53 tetramers in paraffin sections of colorectal cancer tissue. PLA will be further used for detection of p53/p63, p53/p73 and p63/p73 interactions in tumour tissues and it could be also used for screening of compounds that can block formation of p53/p63/p73 protein complexes.Key words: p53 protein family - protein interaction mapping - immunofluorescence This work was supported by MEYS - NPS I

Identification and characterization of suppressors of plant cell death (SPD) effectors from Magnaporthe oryzae.

PubMed

Sharpee, William; Oh, Yeonyee; Yi, Mihwa; Franck, William; Eyre, Alex; Okagaki, Laura H; Valent, Barbara; Dean, Ralph A

2017-08-01

Phytopathogenic microorganisms, including the fungal pathogen Magnaporthe oryzae, secrete a myriad of effector proteins to facilitate infection. Utilizing the transient expression of candidate effectors in the leaves of the model plant Nicotiana benthamiana, we identified 11 suppressors of plant cell death (SPD) effectors from M. oryzae that were able to block the host cell death reaction induced by Nep1. Ten of these 11 were also able to suppress BAX-mediated plant cell death. Five of the 11 SPD genes have been identified previously as either essential for the pathogenicity of M. oryzae, secreted into the plant during disease development, or as suppressors or homologues of other characterized suppressors. In addition, of the remaining six, we showed that SPD8 (previously identified as BAS162) was localized to the rice cytoplasm in invaded and surrounding uninvaded cells during biotrophic invasion. Sequence analysis of the 11 SPD genes across 43 re-sequenced M. oryzae genomes revealed that SPD2, SPD4 and SPD7 have nucleotide polymorphisms amongst the isolates. SPD4 exhibited the highest level of nucleotide diversity of any currently known effector from M. oryzae in addition to the presence/absence polymorphisms, suggesting that this gene is potentially undergoing selection to avoid recognition by the host. Taken together, we have identified a series of effectors, some of which were previously unknown or whose function was unknown, that probably act at different stages of the infection process and contribute to the virulence of M. oryzae. © 2016 BSPP AND JOHN WILEY & SONS LTD.

Chromosome 3 Anomalies Investigated by Genome Wide SNP Analysis of Benign, Low Malignant Potential and Low Grade Ovarian Serous Tumours

PubMed Central

Birch, Ashley H.; Arcand, Suzanna L.; Oros, Kathleen K.; Rahimi, Kurosh; Watters, A. Kevin; Provencher, Diane; Greenwood, Celia M.; Mes-Masson, Anne-Marie; Tonin, Patricia N.

2011-01-01

Ovarian carcinomas exhibit extensive heterogeneity, and their etiology remains unknown. Histological and genetic evidence has led to the proposal that low grade ovarian serous carcinomas (LGOSC) have a different etiology than high grade carcinomas (HGOSC), arising from serous tumours of low malignant potential (LMP). Common regions of chromosome (chr) 3 loss have been observed in all types of serous ovarian tumours, including benign, suggesting that these regions contain genes important in the development of all ovarian serous carcinomas. A high-density genome-wide genotyping bead array technology, which assayed >600,000 markers, was applied to a panel of serous benign and LMP tumours and a small set of LGOSC, to characterize somatic events associated with the most indolent forms of ovarian disease. The genomic patterns inferred were related to TP53, KRAS and BRAF mutations. An increasing frequency of genomic anomalies was observed with pathology of disease: 3/22 (13.6%) benign cases, 40/53 (75.5%) LMP cases and 10/11 (90.9%) LGOSC cases. Low frequencies of chr3 anomalies occurred in all tumour types. Runs of homozygosity were most commonly observed on chr3, with the 3p12-p11 candidate tumour suppressor region the most frequently homozygous region in the genome. An LMP harboured a homozygous deletion on chr6 which created a GOPC-ROS1 fusion gene, previously reported as oncogenic in other cancer types. Somatic TP53, KRAS and BRAF mutations were not observed in benign tumours. KRAS-mutation positive LMP cases displayed significantly more chromosomal aberrations than BRAF-mutation positive or KRAS and BRAF mutation negative cases. Gain of 12p, which harbours the KRAS gene, was particularly evident. A pathology review reclassified all TP53-mutation positive LGOSC cases, some of which acquired a HGOSC status. Taken together, our results support the view that LGOSC could arise from serous benign and LMP tumours, but does not exclude the possibility that HGOSC may derive

Chromosome 3 anomalies investigated by genome wide SNP analysis of benign, low malignant potential and low grade ovarian serous tumours.

PubMed

Birch, Ashley H; Arcand, Suzanna L; Oros, Kathleen K; Rahimi, Kurosh; Watters, A Kevin; Provencher, Diane; Greenwood, Celia M; Mes-Masson, Anne-Marie; Tonin, Patricia N

2011-01-01

Ovarian carcinomas exhibit extensive heterogeneity, and their etiology remains unknown. Histological and genetic evidence has led to the proposal that low grade ovarian serous carcinomas (LGOSC) have a different etiology than high grade carcinomas (HGOSC), arising from serous tumours of low malignant potential (LMP). Common regions of chromosome (chr) 3 loss have been observed in all types of serous ovarian tumours, including benign, suggesting that these regions contain genes important in the development of all ovarian serous carcinomas. A high-density genome-wide genotyping bead array technology, which assayed >600,000 markers, was applied to a panel of serous benign and LMP tumours and a small set of LGOSC, to characterize somatic events associated with the most indolent forms of ovarian disease. The genomic patterns inferred were related to TP53, KRAS and BRAF mutations. An increasing frequency of genomic anomalies was observed with pathology of disease: 3/22 (13.6%) benign cases, 40/53 (75.5%) LMP cases and 10/11 (90.9%) LGOSC cases. Low frequencies of chr3 anomalies occurred in all tumour types. Runs of homozygosity were most commonly observed on chr3, with the 3p12-p11 candidate tumour suppressor region the most frequently homozygous region in the genome. An LMP harboured a homozygous deletion on chr6 which created a GOPC-ROS1 fusion gene, previously reported as oncogenic in other cancer types. Somatic TP53, KRAS and BRAF mutations were not observed in benign tumours. KRAS-mutation positive LMP cases displayed significantly more chromosomal aberrations than BRAF-mutation positive or KRAS and BRAF mutation negative cases. Gain of 12p, which harbours the KRAS gene, was particularly evident. A pathology review reclassified all TP53-mutation positive LGOSC cases, some of which acquired a HGOSC status. Taken together, our results support the view that LGOSC could arise from serous benign and LMP tumours, but does not exclude the possibility that HGOSC may derive

Non-cell-autonomous driving of tumour growth supports sub-clonal heterogeneity.

PubMed

Marusyk, Andriy; Tabassum, Doris P; Altrock, Philipp M; Almendro, Vanessa; Michor, Franziska; Polyak, Kornelia

2014-10-02

Cancers arise through a process of somatic evolution that can result in substantial sub-clonal heterogeneity within tumours. The mechanisms responsible for the coexistence of distinct sub-clones and the biological consequences of this coexistence remain poorly understood. Here we used a mouse xenograft model to investigate the impact of sub-clonal heterogeneity on tumour phenotypes and the competitive expansion of individual clones. We found that tumour growth can be driven by a minor cell subpopulation, which enhances the proliferation of all cells within a tumour by overcoming environmental constraints and yet can be outcompeted by faster proliferating competitors, resulting in tumour collapse. We developed a mathematical modelling framework to identify the rules underlying the generation of intra-tumour clonal heterogeneity. We found that non-cell-autonomous driving of tumour growth, together with clonal interference, stabilizes sub-clonal heterogeneity, thereby enabling inter-clonal interactions that can lead to new phenotypic traits.

Genetic characterization of frameshift suppressors with new decoding properties.

PubMed Central

Hughes, D; Thompson, S; O'Connor, M; Tuohy, T; Nichols, B P; Atkins, J F

1989-01-01

Suppressor mutants that cause ribosomes to shift reading frame at specific and new sequences are described. Suppressors for trpE91, the only known suppressible -1 frameshift mutant, have been isolated in Escherichia coli and in Salmonella typhimurium. E. coli hopR acts on trpE91 within the 9-base-pair sequence GGA GUG UGA, is dominant, and is located at min 52 on the chromosome. Its Salmonella homolog maps at an equivalent position and arises as a rarer class in that organism as compared with E. coli. The Salmonella suppressor, hopE, believed to be in a duplicate copy of the same gene, maps at min 17. The +1 suppressor, sufT, acts at the nonmonotonous sequence CCGU, is dominant, and maps at min 59 on the Salmonella chromosome. PMID:2644219

Tumour-induced osteomalacia.

PubMed

Minisola, Salvatore; Peacock, Munro; Fukumoto, Seijii; Cipriani, Cristiana; Pepe, Jessica; Tella, Sri Harsha; Collins, Michael T

2017-07-13

Tumour-induced osteomalacia (TIO), also known as oncogenic osteomalacia, is a rare paraneoplastic disorder caused by tumours that secrete fibroblast growth factor 23 (FGF23). Owing to the role of FGF23 in renal phosphate handling and vitamin D synthesis, TIO is characterized by decreased renal tubular reabsorption of phosphate, by hypophosphataemia and by low levels of active vitamin D. Chronic hypophosphataemia ultimately results in osteomalacia (that is, inadequate bone mineralization). The diagnosis of TIO is usually suspected when serum phosphate levels are chronically low in the setting of bone pain, fragility fractures and muscle weakness. Locating the offending tumour can be very difficult, as the tumour is often very small and can be anywhere in the body. Surgical removal of the tumour is the only definitive treatment. When the tumour cannot be located or when complete resection is not possible, medical treatment with phosphate salts or active vitamin D is necessary. One of the most promising emerging treatments for unresectable tumours that cause TIO is the anti-FGF23 monoclonal antibody KRN23. The recent identification of a fusion of fibronectin and fibroblast growth factor receptor 1 (FGFR1) as a molecular driver in some tumours not only sheds light on the pathophysiology of TIO but also opens the door to a better understanding of the transcription, translocation, post-translational modification and secretion of FGF23, as well as suggesting approaches to targeted therapy. Further study will reveal if the FGFR1 pathway is also involved in tumours that do not harbour the translocation.

MLLT1 YEATS domain mutations in clinically distinctive Favourable Histology Wilms tumours

PubMed Central

Perlman, Elizabeth J.; Gadd, Samantha; Arold, Stefan T.; Radhakrishnan, Anand; Gerhard, Daniela S.; Jennings, Lawrence; Huff, Vicki; Guidry Auvil, Jaime M.; Davidsen, Tanja M.; Dome, Jeffrey S.; Meerzaman, Daoud; Hsu, Chih Hao; Nguyen, Cu; Anderson, James; Ma, Yussanne; Mungall, Andrew J.; Moore, Richard A.; Marra, Marco A.; Mullighan, Charles G.; Ma, Jing; Wheeler, David A.; Hampton, Oliver A.; Gastier-Foster, Julie M.; Ross, Nicole; Smith, Malcolm A.

2015-01-01

Wilms tumour is an embryonal tumour of childhood that closely resembles the developing kidney. Genomic changes responsible for the development of the majority of Wilms tumours remain largely unknown. Here we identify recurrent mutations within Wilms tumours that involve the highly conserved YEATS domain of MLLT1 (ENL), a gene known to be involved in transcriptional elongation during early development. The mutant MLLT1 protein shows altered binding to acetylated histone tails. Moreover, MLLT1-mutant tumours show an increase in MYC gene expression and HOX dysregulation. Patients with MLLT1-mutant tumours present at a younger age and have a high prevalence of precursor intralobar nephrogenic rests. These data support a model whereby activating MLLT1 mutations early in renal development result in the development of Wilms tumour. PMID:26635203

Detecting truly clonal alterations from multi-region profiling of tumours

PubMed Central

Werner, Benjamin; Traulsen, Arne; Sottoriva, Andrea; Dingli, David

2017-01-01

Modern cancer therapies aim at targeting tumour-specific alterations, such as mutations or neo-antigens, and maximal treatment efficacy requires that targeted alterations are present in all tumour cells. Currently, treatment decisions are based on one or a few samples per tumour, creating uncertainty on whether alterations found in those samples are actually present in all tumour cells. The probability of classifying clonal versus sub-clonal alterations from multi-region profiling of tumours depends on the earliest phylogenetic branching event during tumour growth. By analysing 181 samples from 10 renal carcinoma and 11 colorectal cancers we demonstrate that the information gain from additional sampling falls onto a simple universal curve. We found that in colorectal cancers, 30% of alterations identified as clonal with one biopsy proved sub-clonal when 8 samples were considered. The probability to overestimate clonal alterations fell below 1% in 7/11 patients with 8 samples per tumour. In renal cell carcinoma, 8 samples reduced the list of clonal alterations by 40% with respect to a single biopsy. The probability to overestimate clonal alterations remained as high as 92% in 7/10 renal cancer patients. Furthermore, treatment was associated with more unbalanced tumour phylogenetic trees, suggesting the need of denser sampling of tumours at relapse. PMID:28344344

Detecting truly clonal alterations from multi-region profiling of tumours

NASA Astrophysics Data System (ADS)

Werner, Benjamin; Traulsen, Arne; Sottoriva, Andrea; Dingli, David

2017-03-01

Modern cancer therapies aim at targeting tumour-specific alterations, such as mutations or neo-antigens, and maximal treatment efficacy requires that targeted alterations are present in all tumour cells. Currently, treatment decisions are based on one or a few samples per tumour, creating uncertainty on whether alterations found in those samples are actually present in all tumour cells. The probability of classifying clonal versus sub-clonal alterations from multi-region profiling of tumours depends on the earliest phylogenetic branching event during tumour growth. By analysing 181 samples from 10 renal carcinoma and 11 colorectal cancers we demonstrate that the information gain from additional sampling falls onto a simple universal curve. We found that in colorectal cancers, 30% of alterations identified as clonal with one biopsy proved sub-clonal when 8 samples were considered. The probability to overestimate clonal alterations fell below 1% in 7/11 patients with 8 samples per tumour. In renal cell carcinoma, 8 samples reduced the list of clonal alterations by 40% with respect to a single biopsy. The probability to overestimate clonal alterations remained as high as 92% in 7/10 renal cancer patients. Furthermore, treatment was associated with more unbalanced tumour phylogenetic trees, suggesting the need of denser sampling of tumours at relapse.

PET imaging in adaptive radiotherapy of gastrointestinal tumours.

PubMed

Bulens, Philippe; Thomas, Melissa; Deroose, Christophe M; Haustermans, Karin

2018-06-04

Radiotherapy is the standard of care in the multimodality treatment of a variety of gastrointestinal (GI) tumours, such as oesophageal cancer, gastric cancer, rectal cancer and anal cancer. Additionally, radiotherapy has served as an alternative for surgery in patients with liver cancer, cancer of the biliary tract and pancreatic cancer. Positron-emission tomography (PET), generally in combination with computed tomography (CT), has an established role in the diagnosis, response assessment and (re-)staging of several GI tumours. However, the additional value of PET in adaptive radiotherapy, i.e. during the radiation treatment course and in the delineation process, is still unclear. When performed during radiotherapy, PET aims at assessing treatment-induced variations in functional tumour volumes to reduce the radiation target volume. Moreover, in the radiation treatment planning, tumour delineation could be more accurate by incorporating PET to identify the metabolic tumour volume. This review focuses on the additional value of PET for adaptive radiotherapy protocols as well as for the target volume adaptation for individualised treatment strategies in oesophageal, gastric, pancreatic, liver, biliary tract, rectal and anal neoplasms.

The Eph-Receptor A7 Is a Soluble Tumor Suppressor for Follicular Lymphoma

PubMed Central

Oricchio, Elisa; Nanjangud, Gourd; Wolfe, Andrew L.; Schatz, Jonathan H.; Mavrakis, Konstantinos J.; Jiang, Man; Liu, Xiaoping; Bruno, Joanne; Heguy, Adriana; Olshen, Adam B.; Socci, Nicholas D.; Teruya-Feldstein, J.; Weis-Garcia, Frances; Tam, Wayne; Shaknovich, Rita; Melnick, Ari; Himanen, Juha P.; Chaganti, R.S.K.; Wendel, Hans-Guido

2011-01-01

Insights into cancer genetics can lead to therapeutic opportunities. By cross-referencing chromosomal changes with an unbiased genetic screen we identify the ephrin receptor A7 (EPHA7) as a tumor suppressor in follicular lymphoma (FL). EPHA7 is a target of 6q deletions and inactivated in 72 % of FLs. Knockdown of EPHA7 drives lymphoma development in a murine FL model. In analogy to its physiological function in brain development, a soluble splice variant of EPHA7 (EPHA7TR) interferes with another Eph-receptor and blocks oncogenic signals in lymphoma cells. Consistent with this drug-like activity, administration of the purified EPHA7TR protein produces anti-tumor effects against xenografted human lymphomas. Further, by fusing EPHA7TR to the anti-CD20 antibody (rituximab) we can directly target this tumor suppressor to lymphomas in vivo. Our study attests to the power of combining descriptive tumor genomics with functional screens and reveals EPHA7TR as tumor suppressor with immediate therapeutic potential. PMID:22036564

Parotid gland tumours: MR tractography to assess contact with the facial nerve.

PubMed

Attyé, Arnaud; Karkas, Alexandre; Troprès, Irène; Roustit, Matthieu; Kastler, Adrian; Bettega, Georges; Lamalle, Laurent; Renard, Félix; Righini, Christian; Krainik, Alexandre

2016-07-01

To assess the feasibility of intraparotid facial nerve (VIIn) tractographic reconstructions in estimating the presence of a contact between the VIIn and the tumour, in patients requiring surgical resection of parotid tumours. Patients underwent MR scans with VIIn tractography calculated with the constrained spherical deconvolution model. The parameters of the diffusion sequence were: b-value of 1000 s/mm(2); 32 directions; voxel size: 2 mm isotropic; scan time: 9'31'. The potential contacts between VIIn branches and tumours were estimated with different initial fractional anisotropy (iFA) cut-offs compared to surgical data. Surgeons were blinded to the tractography reconstructions and identified both nerves and contact with tumours using nerve stimulation and reference photographs. Twenty-six patients were included in this study and the mean patient age was 55.2 years. Surgical direct assessment of VIIn allowed identifying 0.1 as the iFA threshold with the best sensitivity to detect tumour contact. In all patients with successful VIIn identification by tractography, surgeons confirmed nerve courses as well as lesion location in parotid glands. Mean VIIn branch FA values were significantly lower in cases with tumour contact (t-test; p ≤ 0.01). This study showed the feasibility of intraparotid VIIn tractography to identify nerve contact with parotid tumours. • Diffusion imaging is an efficient method for highlighting the intraparotid VIIn. • Visualization of the VIIn may help to better manage patients before surgery. • We bring new insights to future trials for patients with VIIn dysfunction. • We aimed to provide radio-anatomical references for further studies.

Tumour-on-a-chip: microfluidic models of tumour morphology, growth and microenvironment

PubMed Central

Trubelja, Alen

2017-01-01

Cancer remains one of the leading causes of death, albeit enormous efforts to cure the disease. To overcome the major challenges in cancer therapy, we need to have a better understanding of the tumour microenvironment (TME), as well as a more effective means to screen anti-cancer drug leads; both can be achieved using advanced technologies, including the emerging tumour-on-a-chip technology. Here, we review the recent development of the tumour-on-a-chip technology, which integrates microfluidics, microfabrication, tissue engineering and biomaterials research, and offers new opportunities for building and applying functional three-dimensional in vitro human tumour models for oncology research, immunotherapy studies and drug screening. In particular, tumour-on-a-chip microdevices allow well-controlled microscopic studies of the interaction among tumour cells, immune cells and cells in the TME, of which simple tissue cultures and animal models are not amenable to do. The challenges in developing the next-generation tumour-on-a-chip technology are also discussed. PMID:28637915

Gastric neuroendocrine tumours.

PubMed

Crosby, David A; Donohoe, Claire L; Fitzgerald, Louise; Muldoon, Cian; Hayes, Brian; O'Toole, Dermot; Reynolds, John V

2012-01-01

Gastric neuroendocrine tumours (NETs) are increasingly recognised, and management decisions may be difficult due to an incomplete understanding of aetiology, natural history and optimum therapy. This article presents a current understanding based on recent advances in epidemiology, classification, molecular profiling, and treatment. Relevant medical literature was identified from searches of PubMed and references cited in appropriate articles identified. Selection of articles was based on peer review, journal and relevance. Gastric NETs may be divided into three clinical prognostic groups: type I is associated with autoimmune atrophic gastritis and hypergastrinaemia, type II is associated with Zollinger-Ellison syndrome, and type III lesions are gastrin-independent, have the greatest metastatic potential and poorest prognosis. There has been an increased frequency of gastric NETs reported. Management approaches have evolved in parallel with advances in endoscopic staging and surgery, as well as improved understanding of the biology and natural history of NETs. Gastric NETs present a spectrum of activity from indolent tumours to metastatic malignancy. Treatment decisions for patients must be individualised and are best managed by a multidisciplinary team approach. The current evidence base is limited to small series and efforts to treat patients within clinical networks of expertise are warranted. Copyright © 2012 S. Karger AG, Basel.

Equine nasal and paranasal sinus tumours. Part 1: review of the literature and tumour classification.

PubMed

Head, K W; Dixon, P M

1999-05-01

The normal gross and histological anatomy of the equine nasal and paranasal sinuses are reviewed and the relationships between the local anatomy, the occurrence of different tumour types, and of tumour spread are examined. The histological classification of the more common equine sinonasal tumours and tumour-like lesions are discussed. Clinical and pathological descriptions of 50 more recently recorded such tumours are separately tabulated. The literature shows that equine sinonasal tumours, both endemic and sporadic, are relatively uncommon in horses, with non-neoplastic growths such as maxillary (sinus) cysts, progressive ethmoid haematoma and inflammatory nasal polyps more commonly recorded. The equine paranasal sinuses, especially the caudal maxillary sinus, are the most common sites for sinonasal tumours and, in contrast to other species, primary nasal tumours are uncommon. The more common tumour types include squamous cell carcinoma that, in some cases, arise in the oral cavity and spread to the maxillary sinuses; adenocarcinomas; bone and dental tumours; fibrosarcomas and haemangiosarcomas. Except for some benign bone tumours, there are few records of successful treatment of equine sinonasal tumours.

Deletion mapping of chromosome 13q in head and neck squamous cell carcinoma in Indian patients: correlation with prognosis of the tumour

PubMed Central

Sabbir, Golam Md; Roy, Anup; Mandal, Syamsundar; Dam, Aniruddha; Roychoudhury, Susanta; Panda, Chinmay Kumar

2006-01-01

Deletions in chromosome (chr.) 13q occur frequently in head and neck squamous cell carcinoma (HNSCC). Previous studies failed to identify common deleted regions in chr.13q, though several candidate tumour suppressor genes (TSGs) loci, e.g. BRCA2, RB1 and BRCAX have been localized in this chromosome, as well as no prognostic significance of the deletion has been reported. Thus, in the present study, deletion mapping of chr. 13q has been done in 55 primary HNSCC samples of Indian patients using 11 highly polymorphic microsatellite markers of which three were intragenic to BRCA2 gene, one intragenic to RB1 gene and another from BRCAX locus. The deletion in chr.13q was significantly associated with progression of HNSCC. High frequencies (27–39%) of loss of heterozygosity were found in 13q13.1 (BRCA2), 13q14.2 (RB1), 13q21.2–22.1 (BRCAX) and 13q31.1 regions. Deletions in the BRCA2 and RB1 regions were significantly correlated. The four highly deleted regions were associated with clinical stage and histological grades of the tumour as well as poor patient outcome. Deletion in the 13q31.1 region was only found to be associated with HPV infection. High frequencies (11–23%) of microsatellite size alteration (MA) were seen to overlap with the highly deleted regions. Forty per cent of the samples showed rare biallelic alteration whereas loss of normal copy of chromosome 13q was seen in five tumours. Thus, it seems that the putative TSGs located in the BRCAX and 13q31.1 regions as well as the BRCA2 and RB1 genes may have some cumulative effect in progression and poor prognosis of HNSCC. Significant association between deletion in BRCA2 and RB1 gene loci may indicate functional relationship between the genes in this tumour progression. PMID:16623759

68Ga-DOTA-TATE PET vs. 123I-MIBG in identifying malignant neural crest tumours.

PubMed

Naji, Meeran; Zhao, Chunlei; Welsh, Sarah J; Meades, Richard; Win, Zarni; Ferrarese, Annalisa; Tan, Tricia; Rubello, Domenico; Al-Nahhas, Adil

2011-08-01

We aimed to compare imaging with (123)I-MIBG and (68)Ga-DOTA-TATE in neural crest tumours (NCT) to see if the latter could offer more advantage in detecting extra lesions and have higher sensitivity for malignant lesions. We retrospectively reviewed 12 patients (M = 10, F = 2; age range 20-71 years) with NCT (phaeochromocytomas = 7, paragangliomas = 4, medullary thyroid cancer = 1) who underwent both (68)Ga-DOTA-TATE positron emission tomography (PET) or PET/computed tomography (CT) and (123)I-MIBG single-photon emission computed tomography within 6 months. Visual assessment of all lesions and measurement of target/non-target (T/N) ratio in selected lesions were performed. Five patients (aged 50 or less) had SDHB screening results correlated with imaging results of both radiopharmaceuticals. All patients had contrast-enhanced CT and/or other cross-sectional imaging. (68)Ga-DOTA-TATE PET showed tumour lesions in ten out of 12 patients with confirmed disease, while (123)I-MIBG showed lesions in five out of 12 patients. In one patient, both (68)Ga-DOTA-TATE PET and (123)I-MIBG were negative, but CT, magnetic resonance imaging, and 2-deoxy-2-[(18)F]fluoro-D-glucose PET scans identified a lesion in the thorax. (68)Ga-DOTA-TATE and (123)I-MIBG detected a total of 30 lesions, of which 29/30 were positive with (68)Ga-DOTA-TATE and 7/30 with (123)I-MIBG. We also found higher incidence of SDHB positive results in patients with positive (68)Ga-DOTA-TATE. Our limited data suggest that (68)Ga-DOTA-TATE is a better imaging agent for NCT and detects significantly more lesions with higher T/N ratio compared to (123)I-MIBG. (68)Ga-DOTA-TATE was more likely to detect malignant lesions as indicated by correlating imaging results with SDHB screening.

An in silico algorithm for identifying stabilizing pockets in proteins: test case, the Y220C mutant of the p53 tumor suppressor protein

PubMed Central

Bromley, Dennis; Bauer, Matthias R.; Fersht, Alan R.; Daggett, Valerie

2016-01-01

The p53 tumor suppressor protein performs a critical role in stimulating apoptosis and cell cycle arrest in response to oncogenic stress. The function of p53 can be compromised by mutation, leading to increased risk of cancer; approximately 50% of cancers are associated with mutations in the p53 gene, the majority of which are in the core DNA-binding domain. The Y220C mutation of p53, for example, destabilizes the core domain by 4 kcal/mol, leading to rapid denaturation and aggregation. The associated loss of tumor suppressor functionality is associated with approximately 75 000 new cancer cases every year. Destabilized p53 mutants can be ‘rescued’ and their function restored; binding of a small molecule into a pocket on the surface of mutant p53 can stabilize its wild-type structure and restore its function. Here, we describe an in silico algorithm for identifying potential rescue pockets, including the algorithm's integration with the Dynameomics molecular dynamics data warehouse and the DIVE visual analytics engine. We discuss the results of the application of the method to the Y220C p53 mutant, entailing finding a putative rescue pocket through MD simulations followed by an in silico search for stabilizing ligands that dock into the putative rescue pocket. The top three compounds from this search were tested experimentally and one of them bound in the pocket, as shown by nuclear magnetic resonance, and weakly stabilized the mutant. PMID:27503952

Similar DNA methylation pattern in lung tumours from smokers and never-smokers with second-hand tobacco smoke exposure.

PubMed

Scesnaite, Asta; Jarmalaite, Sonata; Mutanen, Pertti; Anttila, Sisko; Nyberg, Fredrik; Benhamou, Simone; Boffetta, Paolo; Husgafvel-Pursiainen, Kirsti

2012-07-01

Tobacco smoke causes lung cancer in smokers and in never-smokers exposed to second-hand tobacco smoke (SHS). Nonetheless, molecular mechanisms of lung cancer in SHS-exposed never-smokers are still elusive. We studied lung cancers from current smokers (n = 109), former smokers (n = 56) and never-smokers (n = 47) for promoter hypermethylation of five tumour suppressor genes--p16, RARB, RASSF1, MGMT and DAPK1--using methylation-specific polymerase chain reaction. Lung tumours from ever-smokers suggested an increased risk of p16 hypermethylation as compared to never-smokers (P = 0.073), with former smokers having the highest frequency of p16 hypermethylation (P = 0.044 versus current smokers and P = 0.009 versus never-smokers). In the never-smoking group, p16 hypermethylation was seen in lung tumours from SHS-exposed individuals (4/33; 12%) but in none of the non-exposed individuals (0/9). The overall occurrence of hypermethylation (measured both as methylation index and as number of genes affected) was similar in those ever exposed to tobacco smoke (smokers, SHS-exposed never-smokers) and differed from non-exposed never-smokers. In multivariate analysis, p16 hypermethylation was more prevalent in lung tumours from male than female patients (P = 0.018) and in squamous cell carcinomas than in adenocarcinomas (P = 0.025). Occurrence of TP53 mutation in the tumour was associated with hypermethylation of at least one gene (P = 0.027). In all, our data suggest that promoter hypermethylation pattern in SHS-exposed never-smokers resembles that observed in smokers. Association between TP53 mutation, a hallmark of smokers' lung cancer, and methylation of one or more of the lung cancer-related genes studied, provides further evidence for common tobacco smoke-related origin for both types of molecular alterations.

Genetic analysis of Ikaros target genes and tumor suppressor function in BCR-ABL1+ pre–B ALL

PubMed Central

Aghajanirefah, Ali; McLaughlin, Jami; Cheng, Donghui; Geng, Huimin; Eggesbø, Linn M.; Smale, Stephen T.; Müschen, Markus

2017-01-01

Inactivation of the tumor suppressor gene encoding the transcriptional regulator Ikaros (IKZF1) is a hallmark of BCR-ABL1+ precursor B cell acute lymphoblastic leukemia (pre–B ALL). However, the mechanisms by which Ikaros functions as a tumor suppressor in pre–B ALL remain poorly understood. Here, we analyzed a mouse model of BCR-ABL1+ pre–B ALL together with a new model of inducible expression of wild-type Ikaros in IKZF1 mutant human BCR-ABL1+ pre–B ALL. We performed integrated genome-wide chromatin and expression analyses and identified Ikaros target genes in mouse and human BCR-ABL1+ pre–B ALL, revealing novel conserved gene pathways associated with Ikaros tumor suppressor function. Notably, genetic depletion of different Ikaros targets, including CTNND1 and the early hematopoietic cell surface marker CD34, resulted in reduced leukemic growth. Our results suggest that Ikaros mediates tumor suppressor function by enforcing proper developmental stage–specific expression of multiple genes through chromatin compaction at its target genes. PMID:28190001

Prognostic Value of Occult Isolated Tumour Cells within Regional Lymph Nodes of Dogs with Malignant Mammary Tumours.

PubMed

Coleto, A F; Wilson, T M; Soares, N P; Gundim, L F; Castro, I P; Guimarães, E C; Bandarra, M B; Medeiros-Ronchi, A A

2018-01-01

Canine mammary tumours (CMTs) are the most common type of neoplasm in bitches. As in women, the presence of metastasis in regional lymph nodes is an important prognostic factor in bitches with mammary carcinomas, but the clinical significance of occult isolated tumour cells (ITCs) within lymph nodes is still undefined in this species. The effectiveness of immunohistochemistry (IHC) in identifying occult ITCs and micrometastasis (MIC) was compared with that of the conventional haematoxylin and eosin staining technique. The relationship between tumour size, histological type, histological grade and the presence of metastasis was evaluated. The overall survival (OS) of female dogs with occult mammary carcinomas and ITCs within lymph nodes was analysed. Fragments of mammary carcinoma and regional lymph nodes of 59 female dogs were also evaluated. Histological sections of mammary carcinoma and lymph node samples were studied for tumour diagnosis and lymph node samples were tested by IHC using a pan-cytokeratin antibody. It was found that 35.2% of occult ITCs and 2.8% of hidden MIC were detected when IHC was used. There was a good correlation between the size of the tumour and metastasis to the lymph nodes (P = 0.77). ITCs were observed more frequently in the medullary region (60.7%) and metastases in the cortical region (44.4%). There was no significant difference in the OS between female dogs with occult ITCs and lymph nodes without ITCs. IHC can detect occult tumour cells in lymph nodes that are negative by histopathological examination. Female dogs with nodal ITCs do not have lower survival. Copyright © 2017 Elsevier Ltd. All rights reserved.

The novel WHO 2010 classification for gastrointestinal neuroendocrine tumours correlates well with the metastatic potential of rectal neuroendocrine tumours.

PubMed

Jernman, Juha; Välimäki, Matti J; Louhimo, Johanna; Haglund, Caj; Arola, Johanna

2012-01-01

Approximately 10-15% of gastroenteropancreatic neuroendocrine tumours (NETs, carcinoids) occur in the rectum, some of which are potentially able to metastasize. The new WHO 2010 classification of NETs applies to all gastroenteropancreatic NETs, but no reports have studied its correlation with the prognosis of rectal NETs. We retrospectively classified 73 rectal NETs according to the novel WHO 2010 and the previous WHO 2000 classifications. The aim was to assess the validity of the classifications in distinguishing indolent rectal NETs from metastasising tumours. Using the WHO 2010 criteria, we identified 61 G1 tumours, none of which had metastasised during follow-up. Of 11 G2 tumours, 9 had shown distant metastases. The only G3 neuroendocrine carcinoma that occurred had been disseminated at initial presentation. Our results show that rectal NETs classified as G1 according to the WHO 2010 classification have an indolent clinical course, whereas G2 NETs often metastasise. The WHO 2010 classification of NETs predicts the metastatic potential of rectal NETs better than the WHO 2000 classification. Copyright © 2011 S. Karger AG, Basel.

Resistance to tumour challenge after tumour laser thermotherapy is associated with a cellular immune response

PubMed Central

Ivarsson, K; Myllymäki, L; Jansner, K; Stenram, U; Tranberg, K-G

2005-01-01

Previous studies in our laboratory have shown that interstitial laser thermotherapy (ILT) of an experimental liver tumour is superior to surgical excision, at least partly due to a laser-induced immunological effect. The aim of the present study was to investigate the time–response relationship of the ILT-induced immunisation and the cellular response of macrophages and lymphocytes. A dimethylhydrazine-induced adenocarcinoma was transplanted into the liver of syngeneic rats. Rats with tumour were treated 6–8 days later (tumour size 0.25–0.40 cm3) with ILT of tumour or resection of the tumour-bearing lobe. Two groups of rats without tumour were treated with resection of a normal liver lobe or ILT of normal liver. A challenging tumour was implanted into the liver of each rat 2, 5 or 10 weeks after primary treatment. Rats were killed 6, 12 and 48 days (or earlier due to their condition) after challenge (n=8 in all groups). Immunohistochemical techniques were used to determine lymphocytes (CD8, CD4) and macrophages (ED1, ED2) in rats having had treatment of a primary tumour. Interstitial laser thermotherapy of the first tumour was followed by eradication of challenging tumour and absence of tumour spread. This contrasted with rapid growth and spread of challenging tumour in the other groups. In the challenging vital tumour tissue and in the interface between the tumour and surroundings, the number of ED1 macrophages and CD8 lymphocytes was higher in rats having been treated with the ILT of tumour than in those having undergone resection of the tumour-bearing lobe. The number of ED2 macrophages and CD4 lymphocytes was low and did not vary between these two groups. Interstitial laser thermotherapy elicited an immune response that eradicated a challenging tumour and was associated with increased numbers of tumour-infiltrating macrophages and CD8 lymphocytes. PMID:16091763

Dynamic analysis of periodic vibration suppressors with multiple secondary oscillators

NASA Astrophysics Data System (ADS)

Ma, Jiangang; Sheng, Meiping; Guo, Zhiwei; Qin, Qi

2018-06-01

A periodic vibration suppressor with multiple secondary oscillators is examined in this paper to reduce the low-frequency vibration. The band-gap properties of infinite periodic structure and vibration transmission properties of finite periodic structure attached with secondary oscillators with arbitrary degree of freedom are thoroughly analyzed by the plane-wave-expansion method. A simply supported plate with a periodic rectangular array of vibration suppressors is considered. The dynamic model of this periodic structure is established and the equation of harmonic vibration response is theoretically derived and numerically examined. Compared with the simply supported plate without attached suppressors, the proposed plate can obtain better vibration control, and the vibration response can be effectively reduced in several frequency bands owing to the multiple band-gap property. By analyzing the modal properties of the periodic vibration suppressors, the relationship between modal frequencies and the parameters of spring stiffness and mass is established. With the numerical results, the design guidance of the locally resonant structure with multiple secondary oscillators is proposed to provide practical guidance for application. Finally, a practical periodic specimen is designed and fabricated, and then an experiment is carried out to validate the effectiveness of periodic suppressors in the reality. The results show that the experimental band gaps have a good coincidence with those in the theoretical model, and the low-frequency vibration of the plate with periodic suppressors can be effectively reduced in the tuned band gaps. Both the theoretical results and experimental results prove that the design method is effective and the structure with periodic suppressors has a promising application in engineering.

A theoretical approach to sound propagation and radiation for ducts with suppressors

NASA Technical Reports Server (NTRS)

Rice, E. J.; Sawdy, D. T.

1981-01-01

The several phenomena involved in theoretical prediction of the far-field sound radiation attenuation from an acoustically lined duct were studied. These include absorption by the suppressor, termination reflections, and far-field radiation. Extensive parametric studies show that the suppressor absorption performance can be correlated with mode cut-off ratio or angle of propagation. The other phenomena can be shown to depend explicitly upon mode cut-off ratio. A complete system can thus be generated which can be used to evaluate aircraft sound suppressors and which can be related to the sound source through the cut-off ratio-acoustic power distribution. Although the method is most fully developed for inlet suppressors, several aft radiated noise phenomena are also discussed. This simplified suppressor design and evaluation method is summarized, the recent improvements in the technique are presented, and areas where further refinement is necessary are discussed. Noise suppressor data from engine experiments are compared with the theoretical calculations.

Infrared suppressor effect on T63 turboshaft engine performance

NASA Technical Reports Server (NTRS)

Bailey, E. E.; Civinskas, K. C.; Walker, C. L.

1978-01-01

Tests were conducted to determine if there are performance penalties associated with the installation of infrared (IR) suppressors on the T63-A-700 turboshaft engine. The testing was done in a sea-level, static test cell. The same engine (A-E402808 B) was run with the standard OH-58 aircraft exhaust stacks and with the ejector-type IR suppressors in order to make a valid comparison. Repeatability of the test results for the two configurations was verified by rerunning the conditions over a period of days. Test results showed no measurable difference in performance between the standard exhaust stacks and the IR suppressors.

Enhancement of Recombinant Protein Production in Transgenic Nicotiana benthamiana Plant Cell Suspension Cultures with Co-Cultivation of Agrobacterium Containing Silencing Suppressors.

PubMed

Huang, Ting-Kuo; Falk, Bryce W; Dandekar, Abhaya M; McDonald, Karen A

2018-05-24

We have previously demonstrated that the inducible plant viral vector (CMViva) in transgenic plant cell cultures can significantly improve the productivity of extracellular functional recombinant human alpha-1-antiryspin (rAAT) compared with either a common plant constitutive promoter ( Cauliflower mosaic virus (CaMV) 35S) or a chemically inducible promoter (estrogen receptor-based XVE) system. For a transgenic plant host system, however, viral or transgene-induced post-transcriptional gene silencing (PTGS) has been identified as a host response mechanism that may dramatically reduce the expression of a foreign gene. Previous studies have suggested that viral gene silencing suppressors encoded by a virus can block or interfere with the pathways of transgene-induced PTGS in plant cells. In this study, the capability of nine different viral gene silencing suppressors were evaluated for improving the production of rAAT protein in transgenic plant cell cultures (CMViva, XVE or 35S system) using an Agrobacterium -mediated transient expression co-cultivation process in which transgenic plant cells and recombinant Agrobacterium carrying the viral gene silencing suppressor were grown together in suspension cultures. Through the co-cultivation process, the impacts of gene silencing suppressors on the rAAT production were elucidated, and promising gene silencing suppressors were identified. Furthermore, the combinations of gene silencing suppressors were optimized using design of experiments methodology. The results have shown that in transgenic CMViva cell cultures, the functional rAAT as a percentage of total soluble protein is increased 5.7 fold with the expression of P19, and 17.2 fold with the co-expression of CP, P19 and P24.

Multifocal multi-site Warthin tumour.

PubMed

Hilton, Jennifer M; Phillips, John S; Hellquist, Henrik B; Premachandra, Don J

2008-12-01

The unique case of a 55-year-old man with multifocal adenolymphoma (Warthin's tumour) of both parotid glands, the neck and post-nasal space is presented. Warthin tumour is almost exclusively a parotid tumour but is known to be bilateral in 7-10% of cases and multifocal in 2% of cases. Most extraglandular Warthin tumours have been located in neck lymph nodes and only a few cases have been reported from other sites. The presented case is unique in having synchronous and metachronous Warthin tumours, as well as one of the tumours being neither truly parotid, nor within a lymph node.

Frameshift Suppression in SACCHAROMYCES CEREVISIAE VI. Complete Genetic Map of Twenty-Five Suppressor Genes

PubMed Central

Gaber, Richard F.; Mathison, Lorilee; Edelman, Irv; Culbertson, Michael R.

1983-01-01

Five previously unmapped frameshift suppressor genes have been located on the yeast genetic map. In addition, we have further characterized the map positions of two suppressors whose approximate locations were determined in an earlier study. These results represent the completion of genetic mapping studies on all 25 of the known frameshift suppressor genes in yeast.—The approximate location of each suppressor gene was initially determined through the use of a set of mapping strains containing 61 signal markers distributed throughout the yeast genome. Standard meiotic linkage was assayed in crosses between strains carrying the suppressors and the mapping strains. Subsequent to these approximate linkage determinations, each suppressor gene was more precisely located in multi-point crosses. The implications of these mapping results for the genomic distribution of frameshift suppressor genes, which include both glycine and proline tRNA genes, are discussed. PMID:17246112

A rare case of combined placental site trophoblastic tumour with mature cystic teratoma and mixed germ cell tumour in the testis.

PubMed

Leow, Wei Qiang; Loh, Hwai Liang Alwin; Lee, Lui Shiong; Goh, Chin Hong Ronald

2015-08-01

A 20-year-old male presented with persistent right testicular pain. Following ultrasound detection of testicular nodules and biopsy for intraoperative consultation which yielded germ cell tumour, he underwent radical orchidectomy. A predominantly whitish cyst and a lobulated, variegated nodule were identified. Histology showed a mature cystic teratoma with a focus of infiltrative epithelioid cells containing eosinophilic cytoplasm and pleomorphic nuclei, invading ectatic vessel wall associated with fibrinoid change. These cells were positive for cytokeratin, human placental lactogen and inhibin, while negative for Melan-A, p63 and alpha-fetoprotein, consistent with placental site trophoblastic tumor (PSTT). The variegated nodule was a mixed germ cell tumour composed of embryonal carcinoma and immature teratoma. Aside from choriocarcinoma, primary trophoblastic tumors such as PSTT, which are derived from intermediate trophoblasts, are extremely rare in the testis. Aside from a case of pure testicular PSTT, 2 other cases have been described in association with germ cell tumour, of which one is a mature teratoma with PSTT that demonstrated gain of chromosome 12p. The other presented with PSTT in retroperitoneal recurrence of a testicular mixed germ cell tumour. We discussed the features of this tumour in the testis and important differentials in its diagnosis.

The effect of suppressors and muzzle brakes on shock wave strength

NASA Astrophysics Data System (ADS)

Phan, K. C.; Stollery, J. L.

Experimental simulations of a gun blast were performed in the course of an optimization study of shock-wave suppressor and muzzle-brake geometry. A single-spark schlieren system was used to photograph the shock waves emerging from a 32-mm shock tube. The suppressor systems tested with respect to the overpressure level included a perforated tube enclosed in an expansion chamber, a cup-and-box suppressor, and noise-absorbent materials inside a suppressor; high suppression efficiency was observed for the first two. Recoil simulation tests, performed with plain and pyramidal baffles, disk, and cylinder, show that the blast level is generally higher for a more efective muzzle brake. An optimum distance from the muzzle to the brake is suggested to be in the region of one caliber.

Telomere sequence content can be used to determine ALT activity in tumours

PubMed Central

Lee, Michael; Teber, Erdahl T; Holmes, Oliver; Nones, Katia; Patch, Ann-Marie; Dagg, Rebecca A; Lau, Loretta M S; Lee, Joyce H; Napier, Christine E; Arthur, Jonathan W; Grimmond, Sean M; Hayward, Nicholas K; Johansson, Peter A; Mann, Graham J; Scolyer, Richard A; Wilmott, James S; Reddel, Roger R; Pearson, John V; Waddell, Nicola; Pickett, Hilda A

2018-01-01

Abstract The replicative immortality of human cancer cells is achieved by activation of a telomere maintenance mechanism (TMM). To achieve this, cancer cells utilise either the enzyme telomerase, or the Alternative Lengthening of Telomeres (ALT) pathway. These distinct molecular pathways are incompletely understood with respect to activation and propagation, as well as their associations with clinical outcomes. We have identified significant differences in the telomere repeat composition of tumours that use ALT compared to tumours that do not. We then employed a machine learning approach to stratify tumours according to telomere repeat content with an accuracy of 91.6%. Importantly, this classification approach is applicable across all tumour types. Analysis of pathway mutations that were under-represented in ALT tumours, across 1,075 tumour samples, revealed that the autophagy, cell cycle control of chromosomal replication, and transcriptional regulatory network in embryonic stem cells pathways are involved in the survival of ALT tumours. Overall, our approach demonstrates that telomere sequence content can be used to stratify ALT activity in cancers, and begin to define the molecular pathways involved in ALT activation. PMID:29718321

Unique pathway of expression of an opal suppressor phosphoserine tRNA.

PubMed Central

Lee, B J; de la Peña, P; Tobian, J A; Zasloff, M; Hatfield, D

1987-01-01

An opal suppressor phosphoserine tRNA gene is present in single copy in the genomes of higher vertebrates. We have shown that the product of this gene functions as a suppressor in an in vitro assay, and we have proposed that it may donate a modified amino acid directly to protein in response to specific UGA codons. In this report, we show through in vitro and in vivo studies that the human and Xenopus opal suppressor phosphoserine tRNAs are synthesized by a pathway that is, to the best of our knowledge, unlike that of any known eukaryotic tRNA. The primary transcript of this gene does not contain a 5'-leader sequence; and, therefore, transcription of this suppressor is initiated at the first nucleotide within the coding sequence. The 5'-terminal triphosphate, present on the primary transcript, remains intact through 3'-terminal maturation and through subsequent transport of the tRNA to the cytoplasm. The unique biosynthetic pathway of this opal suppressor may underlie its distinctive role in eukaryotic cells. Images PMID:3114749

An integrated view of suppressor T cell subsets in immunoregulation

PubMed Central

Jiang, Hong; Chess, Leonard

2004-01-01

The immune system evolved to protect organisms from a virtually infinite variety of disease-causing agents but to avoid harmful responses to self. Because immune protective mechanisms include the elaboration of potent inflammatory molecules, antibodies, and killer cell activation — which together can not only destroy invading microorganisms, pathogenic autoreactive cells, and tumors, but also mortally injure normal cells — the immune system is inherently a “double-edged sword” and must be tightly regulated. Immune response regulation includes homeostatic mechanisms intrinsic to the activation and differentiation of antigen-triggered immunocompetent cells and extrinsic mechanisms mediated by suppressor cells. This review series will focus on recent advances indicating that distinct subsets of regulatory CD4+ and CD8+ T cells as well as NK T cells control the outgrowth of potentially pathogenic antigen-reactive T cells and will highlight the evidence that these suppressor T cells may play potentially important clinical roles in preventing and treating immune-mediated disease. Here we provide a historical overview of suppressor cells and the experimental basis for the existence of functionally and phenotypically distinct suppressor subsets. Finally, we will speculate on how the distinct suppressor cell subsets may function in concert to regulate immune responses. PMID:15520848

Genetic Characterization of the SufJ Frameshift Suppressor in SALMONELLA TYPHIMURIUM

PubMed Central

Bossi, Lionello; Kohno, Tadahiko; Roth, John R.

1983-01-01

A new suppressor of +1 frameshift mutations has been isolated in Salmonella typhimurium. This suppressor, sufJ, maps at minute 89 on the Salmonella genetic map between the argH and rpo(rif) loci, closely linked to the gene for the ochre suppressor tyrU(supM). The suppressor mutation is dominant to its wild-type allele, consistent with the suppressor phenotype being caused by an altered tRNA species. The sufJ map position coincides with that of a threonine tRNA(ACC/U) gene; the suppressor has been shown to read the related fourbase codons ACCU, ACCC, ACCA.—The ability of sufJ to correct one particular mutation depends on the presence of a hisT mutation which causes a defect in tRNA modification. This requirement is allele specific, since other frameshift mutations can be corrected by sufJ regardless of the state of the hisT locus.—Strains carrying both a sufJ and a hisT mutation are acutely sensitive to growth inhibition by uracil; the inhibition is reversed by arginine. This behavior is characteristic of strains with mutations affecting the arginine-uracil biosynthetic enzyme carbamyl phosphate synthetase. The combination of two mutations affecting tRNA structure may reduce expression of the structural gene for this enzyme (pyrA). PMID:6188650

Adapting radiotherapy to hypoxic tumours

NASA Astrophysics Data System (ADS)

Malinen, Eirik; Søvik, Åste; Hristov, Dimitre; Bruland, Øyvind S.; Rune Olsen, Dag

2006-10-01

In the current work, the concepts of biologically adapted radiotherapy of hypoxic tumours in a framework encompassing functional tumour imaging, tumour control predictions, inverse treatment planning and intensity modulated radiotherapy (IMRT) were presented. Dynamic contrast enhanced magnetic resonance imaging (DCEMRI) of a spontaneous sarcoma in the nasal region of a dog was employed. The tracer concentration in the tumour was assumed related to the oxygen tension and compared to Eppendorf histograph measurements. Based on the pO2-related images derived from the MR analysis, the tumour was divided into four compartments by a segmentation procedure. DICOM structure sets for IMRT planning could be derived thereof. In order to display the possible advantages of non-uniform tumour doses, dose redistribution among the four tumour compartments was introduced. The dose redistribution was constrained by keeping the average dose to the tumour equal to a conventional target dose. The compartmental doses yielding optimum tumour control probability (TCP) were used as input in an inverse planning system, where the planning basis was the pO2-related tumour images from the MR analysis. Uniform (conventional) and non-uniform IMRT plans were scored both physically and biologically. The consequences of random and systematic errors in the compartmental images were evaluated. The normalized frequency distributions of the tracer concentration and the pO2 Eppendorf measurements were not significantly different. 28% of the tumour had, according to the MR analysis, pO2 values of less than 5 mm Hg. The optimum TCP following a non-uniform dose prescription was about four times higher than that following a uniform dose prescription. The non-uniform IMRT dose distribution resulting from the inverse planning gave a three times higher TCP than that of the uniform distribution. The TCP and the dose-based plan quality depended on IMRT parameters defined in the inverse planning procedure (fields

Genome-wide association study identifies novel susceptibility loci for cutaneous squamous cell carcinoma.

PubMed

Chahal, Harvind S; Lin, Yuan; Ransohoff, Katherine J; Hinds, David A; Wu, Wenting; Dai, Hong-Ji; Qureshi, Abrar A; Li, Wen-Qing; Kraft, Peter; Tang, Jean Y; Han, Jiali; Sarin, Kavita Y

2016-07-18

Cutaneous squamous cell carcinoma represents the second most common cutaneous malignancy, affecting 7-11% of Caucasians in the United States. The genetic determinants of susceptibility to cutaneous squamous cell carcinoma remain largely unknown. Here we report the results of a two-stage genome-wide association study of cutaneous squamous cell carcinoma, totalling 7,404 cases and 292,076 controls. Eleven loci reached genome-wide significance (P<5 × 10(-8)) including seven previously confirmed pigmentation-related loci: MC1R, ASIP, TYR, SLC45A2, OCA2, IRF4 and BNC2. We identify an additional four susceptibility loci: 11q23.3 CADM1, a metastasis suppressor gene involved in modifying tumour interaction with cell-mediated immunity; 2p22.3; 7p21.1 AHR, the dioxin receptor involved in anti-apoptotic pathways and melanoma progression; and 9q34.3 SEC16A, a putative oncogene with roles in secretion and cellular proliferation. These susceptibility loci provide deeper insight into the pathogenesis of squamous cell carcinoma.

Aero-acoustic performance comparison of core engine noise suppressors on NASA quiet engine C

NASA Technical Reports Server (NTRS)

Bloomer, H. E.; Schaefer, J. W.

1977-01-01

The relative aero-acoustic effectiveness of two core engine suppressors, a contractor-designed suppressor delivered with the Quiet Engine, and a NASA-designed suppressor was evaluated. The NASA suppressor was tested with and without a splitter making a total of three configurations being reported in addition to the baseline hardwall case. The aerodynamic results are presented in terms of tailpipe pressure loss, corrected net thrust, and corrected specific fuel consumption as functions of engine power setting. The acoustic results are divided into duct and far-field acoustic data. The NASA-designed core suppressor did the better job of suppressing aft end noise, but the splitter associated with it caused a significant engine performance penality. The NASA core suppressor without the spltter suppressed most of the core noise without any engine performance penalty.

Cancer-derived extracellular vesicles: friend and foe of tumour immunosurveillance.

PubMed

Dörsam, Bastian; Reiners, Kathrin S; von Strandmann, Elke Pogge

2018-01-05

Extracellular vesicles (EVs) are important players of intercellular signalling mechanisms, including communication with and among immune cells. EVs can affect the surrounding tissue as well as peripheral cells. Recently, EVs have been identified to be involved in the aetiology of several diseases, including cancer. Tumour cell-released EVs or exosomes have been shown to promote a tumour-supporting environment in non-malignant tissue and, thus, benefit metastasis. The underlying mechanisms are numerous: loss of antigen expression, direct suppression of immune effector cells, exchange of nucleic acids, alteration of the recipient cells' transcription and direct suppression of immune cells. Consequently, tumour cells can subvert the host's immune detection as well as suppress the immune system. On the contrary, recent studies reported the existence of EVs able to activate immune cells, thus promoting the tumour-directed immune response. In this article, the immunosuppressive capabilities of EVs, on the one hand, and their potential use in immunoactivation and therapeutic potential, on the other hand, are discussed.This article is part of the discussion meeting issue 'Extracellular vesicles and the tumour microenvironment'. © 2017 The Authors.

[Surgical Management of Peritoneal Surface Malignancy with Respect to Tumour Type, Tumour Stage and Individual Tumour Biology].

PubMed

Beckert, S; Struller, F; Grischke, E-M; Glatzle, J; Zieker, D; Königsrainer, A; Königsrainer, I

2016-08-01

Peritoneal tumour dissemination is still considered as a terminal disease. For the last two decades, cytoreductive surgery (CRS) combined with intraoperative hyperthermic chemotherapy (HIPEC) has been popularised by Paul Sugarbaker almost doubling survival in selected patients compared with systemic chemotherapy alone. Nowadays, this particular treatment protocol is available in comprehensive cancer centres with reasonable mortality and morbidity. However, patient selection is still challenging. In general, CRS and HIPEC is indicated in primary peritoneal tumours such as mesothelioma and pseudomyxoma peritonei as well as in peritoneal metastases derived from gastrointestinal malignancies and ovarian cancers. Since systemic tumour spread is uncommon in patients with peritoneal metastases, peritoneal tumour dissemination was defined as localised disease within the "compartment abdomen". However, CRS and HIPEC are only beneficial as long as complete cytoreduction is achieved (CC-0 or CC-1). Histopathological parameters, the Sugarbaker peritoneal carcinomatosis index (PCI) and general condition of the patient have been established as patient selection criteria. In primary peritoneal cancers, individual tumour biology is the predominant criterium for patient selection as opposed to intraabdominal tumour load in peritoneal metastases derived from gastrointestinal cancers. In gastric cancer, CRS and HIPEC should be restricted to synchronous limited disease because of its biological aggressiveness. In patients with free floating cancer cells without macroscopic signs of peritoneal spread, however, CRS and HIPEC following preoperative "neoadjuvant" chemotherapy preserves chances for cure. So far, there is no general recommendation for CRS and HIPEC by clinical practice guidelines. In the recent S3 guideline for treatment of colorectal cancer, however, CRS and HIPEC have been included as possible treatment options. Georg Thieme Verlag KG Stuttgart · New York.

Lysyl oxidase-like-2 promotes tumour angiogenesis and is a potential therapeutic target in angiogenic tumours.

PubMed

Zaffryar-Eilot, Shelly; Marshall, Derek; Voloshin, Tali; Bar-Zion, Avinoam; Spangler, Rhyannon; Kessler, Ofra; Ghermazien, Haben; Brekhman, Vera; Suss-Toby, Edith; Adam, Dan; Shaked, Yuval; Smith, Victoria; Neufeld, Gera

2013-10-01

Lysyl oxidase-like 2 (LOXL2), a secreted enzyme that catalyzes the cross-linking of collagen, plays an essential role in developmental angiogenesis. We found that administration of the LOXL2-neutralizing antibody AB0023 inhibited bFGF-induced angiogenesis in Matrigel plug assays and suppressed recruitment of angiogenesis promoting bone marrow cells. Small hairpin RNA-mediated inhibition of LOXL2 expression or inhibition of LOXL2 using AB0023 reduced the migration and network-forming ability of endothelial cells, suggesting that the inhibition of angiogenesis results from a direct effect on endothelial cells. To examine the effects of AB0023 on tumour angiogenesis, AB0023 was administered to mice bearing tumours derived from SKOV-3 ovarian carcinoma or Lewis lung carcinoma (LLC) cells. AB0023 treatment significantly reduced the microvascular density in these tumours but did not inhibit tumour growth. However, treatment of mice bearing SKOV-3-derived tumours with AB0023 also promoted increased coverage of tumour vessels with pericytes and reduced tumour hypoxia, providing evidence that anti-LOXL2 therapy results in the normalization of tumour blood vessels. In agreement with these data, treatment of mice bearing LLC-derived tumours with AB0023 improved the perfusion of the tumour-associated vessels as determined by ultrasonography. Improved perfusion and normalization of tumour vessels after treatment with anti-angiogenic agents were previously found to improve the delivery of chemotherapeutic agents into tumours and to result in an enhancement of chemotherapeutic efficiency. Indeed, treatment with AB0023 significantly enhanced the anti-tumourigenic effects of taxol. Our results suggest that inhibition of LOXL2 may prove beneficial for the treatment of angiogenic tumours.

Metastasis is regulated via microRNA-200/ZEB1 axis control of tumour cell PD-L1 expression and intratumoral immunosuppression.

PubMed

Chen, Limo; Gibbons, Don L; Goswami, Sangeeta; Cortez, Maria Angelica; Ahn, Young-Ho; Byers, Lauren A; Zhang, Xuejun; Yi, Xiaohui; Dwyer, David; Lin, Wei; Diao, Lixia; Wang, Jing; Roybal, Jonathon; Patel, Mayuri; Ungewiss, Christin; Peng, David; Antonia, Scott; Mediavilla-Varela, Melanie; Robertson, Gordon; Suraokar, Milind; Welsh, James W; Erez, Baruch; Wistuba, Ignacio I; Chen, Lieping; Peng, Di; Wang, Shanshan; Ullrich, Stephen E; Heymach, John V; Kurie, Jonathan M; Qin, F Xiao-Feng

2014-10-28

Immunosuppression of tumour-infiltrating lymphocytes (TIL) is a common feature of advanced cancer, but its biological basis has remained obscure. We demonstrate here a molecular link between epithelial-to-mesenchymal transition (EMT) and CD8(+) TIL immunosuppression, two key drivers of cancer progression. We show that microRNA-200 (miR-200), a cell-autonomous suppressor of EMT and metastasis, targets PD-L1. Moreover, ZEB1, an EMT activator and transcriptional repressor of miR-200, relieves miR-200 repression of PD-L1 on tumour cells, leading to CD8(+) T-cell immunosuppression and metastasis. These findings are supported by robust correlations between the EMT score, miR-200 levels and PD-L1 expression in multiple human lung cancer datasets. In addition to revealing a link between EMT and T-cell dysfunction, these findings also show that ZEB1 promotes metastasis through a heretofore unappreciated cell non-autonomous mechanism, and suggest that subgroups of patients in whom malignant progression is driven by EMT activators may respond to treatment with PD-L1 antagonists.

Inverse relationship between cirrhosis and massive tumours in hepatocellular carcinoma.

PubMed

Sarpel, Umut; Ayo, Diego; Lobach, Iryna; Xu, Ruliang; Newman, Elliot

2012-11-01

A subset of patients with hepatocellular carcinoma (HCC) present with massive tumours. It is unknown why certain patients develop these massive tumours, and whether this presentation is specific to the underlying viral aetiology or patient demographics such as gender, race and age. All patients with HCC at Bellevue Hospital Center, New York from 1998 to 2012 were identified and relevant demographic and clinical information was collected. Computed tomography/magnetic resonance imaging (CT/MRI) images were reviewed and the maximal tumour diameter on axial sections was recorded. Cirrhosis was defined histologically or by radiographical criteria. The two cohorts of massive and non-massive HCC were compared. A total of 361 patients with HCC were identified, of which 58 were categorized as having a massive HCC using a 13 cm size cut-off. Univariate and multivariate analysis demonstrated a significant association of massive HCC with age <40 years; hepatitis B or Asian ethnicity; and a lack of cirrhosis or platelet count >100. Massive HCC represents a tumour subtype that is associated with young, chronic hepatitis B carriers with non-cirrhotic livers. The clinical implications of this finding are that patients with massive HCC are typically excellent resection candidates barring the presence of gross vascular invasion or distant metastases. © 2012 International Hepato-Pancreato-Biliary Association.

WISP-2 in human gastric cancer and its potential metastatic suppressor role in gastric cancer cells mediated by JNK and PLC-γ pathways.

PubMed

Ji, Jiafu; Jia, Shuqin; Jia, Yongning; Ji, Ke; Hargest, Rachel; Jiang, Wen G

2015-09-15

It has recently been shown that WISP proteins (Wnt-inducted secreted proteins), a group of intra- and extra-cellular regulatory proteins, have been implicated in the initiation and progression of a variety of tumour types including colorectal and breast cancer. However, the role of WISP proteins in gastric cancer (GC) cells and their clinical implications have not yet been elucidated. The expression of WISP molecules in a cohort of GC patients was analysed using real-time quantitative PCR and immunohistochemistry. The expression of a panel of recognised epithelial-mesenchymal transition (EMT) markers was quantified using Q-PCR in paired tumour and normal tissues. WISP-2 knockdown (kd) sublines using ribozyme transgenes were created in the GC cell lines AGS and HGC27. Subsequently, several biological functions, including cell growth, adhesion, migration and invasion, were studied. Potential pathways for the interaction of EMT, extracellular matrix and MMP were evaluated. Overexpression of WISP-2 was detected in GC and significantly correlated with early tumour node-metastasis staging, differentiation status and positively correlated with overall survival and disease-free survival of the patients. WISP-2 expression was inversely correlated with that of Twist and Slug in paired samples. Kd of WISP-2 expression promoted the proliferation, migration and invasion of GC cells. WISP-2 suppressed GC cell metastasis through reversing EMT and suppressing the expression and activity of MMP9 and MMP2 via JNK and ERK. Cell motility analysis indicated that WISP-2 kd contributed to GC cells' motility and can be attenuated by PLC-γ and JNK small inhibitors. Increased expression of WISP-2 in GC is positively correlated with favourable clinical features and the survival of patients with GC and is a negative regulator of growth, migration and invasion in GC cells. These findings suggest that WISP-2 is a potential tumour suppressor in GC.

Targeting PTPRK-RSPO3 colon tumours promotes differentiation and loss of stem-cell function.

PubMed

Storm, Elaine E; Durinck, Steffen; de Sousa e Melo, Felipe; Tremayne, Jarrod; Kljavin, Noelyn; Tan, Christine; Ye, Xiaofen; Chiu, Cecilia; Pham, Thinh; Hongo, Jo-Anne; Bainbridge, Travis; Firestein, Ron; Blackwood, Elizabeth; Metcalfe, Ciara; Stawiski, Eric W; Yauch, Robert L; Wu, Yan; de Sauvage, Frederic J

2016-01-07

Colorectal cancer remains a major unmet medical need, prompting large-scale genomics efforts in the field to identify molecular drivers for which targeted therapies might be developed. We previously reported the identification of recurrent translocations in R-spondin genes present in a subset of colorectal tumours. Here we show that targeting RSPO3 in PTPRK-RSPO3-fusion-positive human tumour xenografts inhibits tumour growth and promotes differentiation. Notably, genes expressed in the stem-cell compartment of the intestine were among those most sensitive to anti-RSPO3 treatment. This observation, combined with functional assays, suggests that a stem-cell compartment drives PTPRK-RSPO3 colorectal tumour growth and indicates that the therapeutic targeting of stem-cell properties within tumours may be a clinically relevant approach for the treatment of colorectal tumours.

Molecular crosstalk between tumour and brain parenchyma instructs histopathological features in glioblastoma.

PubMed

Bougnaud, Sébastien; Golebiewska, Anna; Oudin, Anaïs; Keunen, Olivier; Harter, Patrick N; Mäder, Lisa; Azuaje, Francisco; Fritah, Sabrina; Stieber, Daniel; Kaoma, Tony; Vallar, Laurent; Brons, Nicolaas H C; Daubon, Thomas; Miletic, Hrvoje; Sundstrøm, Terje; Herold-Mende, Christel; Mittelbronn, Michel; Bjerkvig, Rolf; Niclou, Simone P

2016-05-31

The histopathological and molecular heterogeneity of glioblastomas represents a major obstacle for effective therapies. Glioblastomas do not develop autonomously, but evolve in a unique environment that adapts to the growing tumour mass and contributes to the malignancy of these neoplasms. Here, we show that patient-derived glioblastoma xenografts generated in the mouse brain from organotypic spheroids reproducibly give rise to three different histological phenotypes: (i) a highly invasive phenotype with an apparent normal brain vasculature, (ii) a highly angiogenic phenotype displaying microvascular proliferation and necrosis and (iii) an intermediate phenotype combining features of invasion and vessel abnormalities. These phenotypic differences were visible during early phases of tumour development suggesting an early instructive role of tumour cells on the brain parenchyma. Conversely, we found that tumour-instructed stromal cells differentially influenced tumour cell proliferation and migration in vitro, indicating a reciprocal crosstalk between neoplastic and non-neoplastic cells. We did not detect any transdifferentiation of tumour cells into endothelial cells. Cell type-specific transcriptomic analysis of tumour and endothelial cells revealed a strong phenotype-specific molecular conversion between the two cell types, suggesting co-evolution of tumour and endothelial cells. Integrative bioinformatic analysis confirmed the reciprocal crosstalk between tumour and microenvironment and suggested a key role for TGFβ1 and extracellular matrix proteins as major interaction modules that shape glioblastoma progression. These data provide novel insight into tumour-host interactions and identify novel stroma-specific targets that may play a role in combinatorial treatment strategies against glioblastoma.

Infective complications following tumour endoprosthesis surgery for bone and soft tissue tumours.

PubMed

Peel, T; May, D; Buising, K; Thursky, K; Slavin, M; Choong, P

2014-09-01

This study aims to describe the incidence of infective complications, including tumour endoprosthesis infection, in a cohort of patients undergoing tumour endoprosthesis surgery in Victoria, Australia. This retrospective cohort study was performed over 15 years (January 1996-December 2010). 121 patients underwent tumour endoprosthesis surgery during the study period. Patients were followed for a median of 34 months (interquartile range [IQR] 17, 80). Overall, 34 patients (28%) experienced infective complications including: bacteraemia in 19 patients (16%) and tumour endoprosthesis infection in 17 (14%). The majority of patients with early and late acute infections (haematogenous) were managed with debridement and retention of the prosthesis in addition to biofilm-active antibiotics. Late chronic infections were predominantly managed by exchange of the prosthesis. The overall success rate of treatment was 71%. The success rate for debridement and retention was 75% compared with 67% for exchange procedures. There is a significant rate of infective complications following tumour endoprosthesis surgery including 14% of patients experiencing infection involving the tumour endoprosthesis. This study is the first to report on outcomes from debridement and retention of the prosthesis; which had comparable success rates to other treatment modalities. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

MLLT1 YEATS domain mutations in clinically distinctive Favourable Histology Wilms tumours | Office of Cancer Genomics

Cancer.gov

Wilms tumour is an embryonal tumour of childhood that closely resembles the developing kidney. Genomic changes responsible for the development of the majority of Wilms tumours remain largely unknown. Here we identify recurrent mutations within Wilms tumours that involve the highly conserved YEATS domain of MLLT1 (ENL), a gene known to be involved in transcriptional elongation during early development. The mutant MLLT1 protein shows altered binding to acetylated histone tails.

Prognostic relevance of microvessel density in colorectal tumours.

PubMed

Abdalla, S A; Behzad, F; Bsharah, S; Kumar, S; Amini, S K; O'Dwyer, S T; Haboubi, N Y

1999-01-01

The importance of angiogenesis as a prognostic marker has been examined in 111 colorectal cancer patients with a minimum follow-up of 5 years. Tumour sections were immunostained with pan-endothelial antibody to CD31. Microvessels were identified and counted in 5 separate areas of highest vascularity (). Analysis of the data showed that the survival was not significantly affected by tumour site, size, grade, patients' age or gender. However, a statistically significant correlation was found between microvessel density (MVD) and survival: patients with an increased number of microvessels survived longer than those with a low number of microvessels (p=0.0007). Therefore, paradoxically, unlike other tumour types, in colorectal cancer MVD appears to be an indicator of good prognosis. The reasons that MVD correlates with good or poor prognosis are likely to vary in different tumours. For instance a frequent difficult issue in colon cancer is the presence of ulceration and adjacent severe inflammation which by itself can increase vascularity. Furthermore, overall prognosis will also depend on other factors, such as oncogenes, extracellular matrix components, adhesion molecules, growth factors, degree of apoptosis and the mode of metastatic spread.

Magnetic resonance spectroscopy metabolite profiles predict survival in paediatric brain tumours.

PubMed

Wilson, Martin; Cummins, Carole L; Macpherson, Lesley; Sun, Yu; Natarajan, Kal; Grundy, Richard G; Arvanitis, Theodoros N; Kauppinen, Risto A; Peet, Andrew C

2013-01-01

Brain tumours cause the highest mortality and morbidity rate of all childhood tumour groups and new methods are required to improve clinical management. (1)H magnetic resonance spectroscopy (MRS) allows non-invasive concentration measurements of small molecules present in tumour tissue, providing clinically useful imaging biomarkers. The primary aim of this study was to investigate whether MRS detectable molecules can predict the survival of paediatric brain tumour patients. Short echo time (30ms) single voxel (1)H MRS was performed on children attending Birmingham Children's Hospital with a suspected brain tumour and 115 patients were included in the survival analysis. Patients were followed-up for a median period of 35 months and Cox-Regression was used to establish the prognostic value of individual MRS detectable molecules. A multivariate model of survival was also investigated to improve prognostic power. Lipids and scyllo-inositol predicted poor survival whilst glutamine and N-acetyl aspartate predicted improved survival (p<0.05). A multivariate model of survival based on three MRS biomarkers predicted survival with a similar accuracy to histologic grading (p<5e-5). A negative correlation between lipids and glutamine was found, suggesting a functional link between these molecules. MRS detectable biomolecules have been identified that predict survival of paediatric brain tumour patients across a range of tumour types. The evaluation of these biomarkers in large prospective studies of specific tumour types should be undertaken. The correlation between lipids and glutamine provides new insight into paediatric brain tumour metabolism that may present novel targets for therapy. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Ras effector RASSF2 is a novel tumor-suppressor gene in human colorectal cancer.

PubMed

Akino, Kimishige; Toyota, Minoru; Suzuki, Hiromu; Mita, Hiroaki; Sasaki, Yasushi; Ohe-Toyota, Mutsumi; Issa, Jean-Pierre J; Hinoda, Yuji; Imai, Kohzoh; Tokino, Takashi

2005-07-01

Activation of Ras signaling is a hallmark of colorectal cancer (CRC), but the roles of negative regulators of Ras are not fully understood. Our aim was to address that question by surveying genetic and epigenetic alterations of Ras-Ras effector genes in CRC cells. The expression and methylation status of 6 RASSF family genes were examined using RT-PCR and bisulfite PCR in CRC cell lines and in primary CRCs and colorectal adenomas. Colony formation assays and flow cytometry were used to assess the tumor suppressor activities of RASSF1 and RASSF2. Immunofluorescence microscopy was used to determine the effect of altered RASSF2 expression on cell morphology. Mutations of K- ras , BRAF, and p53 were identified using single-strand conformation analysis and direct sequencing. Aberrant methylation and histone deacetylation of RASSF2 was associated with the gene's silencing in CRC. The activities of RASSF2, which were distinct from those of RASSF1, included induction of morphologic changes and apoptosis; moreover, its ability to prevent cell transformation suggests that RASSF2 acts as a tumor suppressor in CRC. Primary CRCs that showed K- ras /BRAF mutations also frequently showed RASSF2 methylation, and inactivation of RASSF2 enhanced K- ras -induced oncogenic transformation. RASSF2 methylation was also frequently identified in colorectal adenomas. RASSF2 is a novel tumor suppressor gene that regulates Ras signaling and plays a pivotal role in the early stages of colorectal tumorigenesis.

Aero-acoustic performance comparison of core engine noise suppressors on NASA quiet engine 'C'

NASA Technical Reports Server (NTRS)

Bloomer, H. E.; Schaefer, J. W.

1977-01-01

The purpose of the experimental program reported herein was to evaluate and compare the relative aero-acoustic effectiveness of two core engine suppressors, a contractor-designed suppressor delivered with the Quiet Engine, and a NASA-designed suppressor, designed and built subsequently. The NASA suppressor was tested with and without a splitter making a total of three configurations being reported in addition to the baseline hardwall case. The aerodynamic results are presented in terms of tailpipe pressure loss, corrected net thrust, and corrected specific fuel consumption as functions of engine power setting. The acoustic results are divided into duct and far-field acoustic data. The NASA-designed core suppressor did the better job of suppressing aft end noise, but the splitter associated with it caused a significant engine performance penalty. The NASA core suppressor without the splitter suppressed most of the core noise without any engine performance penalty.

Anti-tumour activity of a novel coumarin-chalcone hybrid is mediated through intrinsic apoptotic pathway by inducing PUMA and altering Bax/Bcl-2 ratio.

PubMed

Singh, Neetu; Sarkar, Jayanta; Sashidhara, Koneni V; Ali, Shakir; Sinha, Sudhir

2014-06-01

Coumarins and chalcones are secondary plant metabolites which have shown an array of pharmacological properties including anti-tumour activity. We have previously reported on the synthesis and anti-proliferative activity of a series of novel coumarin-chalcone hybrids. Now we report on the in vivo efficacy as well as mechanism of action of the most potent molecule of the series, S009-131. Oral administration of this molecule resulted in regression of tumours induced by HeLa cell xenografts in nod SCID mice. The molecule inhibited proliferation of cervical cancer cells (HeLa and C33A) by inducing apoptosis and arresting cell cycle at G2/M phase. Apoptosis was induced through induction of caspase-dependent intrinsic pathway and alterations in the cellular levels of Bcl-2 family proteins. The mitochondrial transmembrane potential got highly depleted in S009-131 treated cells due to an increase in Bax/Bcl-2 ratio and intracellular ROS. The molecule induced release of cytochrome c into the cytosol and activation of initiator caspase-9 and executioner caspases-3/7. Tumour suppressor protein p53 and its transcriptional target PUMA were up regulated, suggesting their role in mediating the cell death. These results suggest that S009-131 is a potent candidate for the chemotherapy of cervical carcinoma.

[Why are carotid glomus tumours dangerous?].

PubMed

Certík, B; Třeška, V

2014-10-01

Carotid body tumours are rare, usually benign tumours. The dangerous nature of carotid body tumours is due to their hypervascularization and the intimate relationship to cervical arteries and cranial nerves. In a case report, the authors document that misdiagnosis and efforts to remove or obtain a biopsy of the tumour outside vascular centres can be more dangerous for the patient than the nature of the tumour itself.

Tumours of bones and joints

PubMed Central

Misdorp, W.; Van Der Heul, R. O.

1976-01-01

Tumours of bones and joints are not infrequent in dogs but are rare in other domestic animals. In the dog, most bone tumours are malignant; osteosarcomas are by far the most frequently encountered tumours, especially in giant breeds and boxers. The following main categories of bone tumour are described: bone-forming, cartilage-forming, giant cell, marrow, vascular, miscellaneous, metastatic, unclassified, and tumour-like lesions. The tumours of joints and related structures are classified as synovial sarcomas, fibroxanthomas, and malignant giant cell tumour of soft tissues. ImagesFig. 21Fig. 22Fig. 23Fig. 24Fig. 17Fig. 18Fig. 19Fig. 20Fig. 29Fig. 30Fig. 31Fig. 32Fig. 33Fig. 34Fig. 35Fig. 36Fig. 25Fig. 26Fig. 27Fig. 28Fig. 1Fig. 2Fig. 3Fig. 4Fig. 37Fig. 38Fig. 39Fig. 40Fig. 5Fig. 6Fig. 7Fig. 8Fig. 13Fig. 14Fig. 15Fig. 16Fig. 9Fig. 10Fig. 11Fig. 12 PMID:1086157

CRISPR screen identifies the NCOR/HDAC3 complex as a major suppressor of differentiation in rhabdomyosarcoma

PubMed Central

Phelps, Michael P.; Bailey, Jenna N.; Vleeshouwer-Neumann, Terra

2016-01-01

Dysregulated gene expression resulting from abnormal epigenetic alterations including histone acetylation and deacetylation has been demonstrated to play an important role in driving tumor growth and progression. However, the mechanisms by which specific histone deacetylases (HDACs) regulate differentiation in solid tumors remains unclear. Using pediatric rhabdomyosarcoma (RMS) as a paradigm to elucidate the mechanism blocking differentiation in solid tumors, we identified HDAC3 as a major suppressor of myogenic differentiation from a high-efficiency Clustered regularly interspaced short palindromic repeats (CRISPR)-based phenotypic screen of class I and II HDAC genes. Detailed characterization of the HDAC3-knockout phenotype in vitro and in vivo using a tamoxifen-inducible CRISPR targeting strategy demonstrated that HDAC3 deacetylase activity and the formation of a functional complex with nuclear receptor corepressors (NCORs) were critical in restricting differentiation in RMS. The NCOR/HDAC3 complex specifically functions by blocking myoblast determination protein 1 (MYOD1)-mediated activation of myogenic differentiation. Interestingly, there was also a transient up-regulation of growth-promoting genes upon initial HDAC3 targeting, revealing a unique cancer-specific response to the forced transition from a neoplastic state to terminal differentiation. Our study applied modifications of CRISPR/CRISPR-associated endonuclease 9 (Cas9) technology to interrogate the function of essential cancer genes and pathways and has provided insights into cancer cell adaptation in response to altered differentiation status. Because current pan-HDAC inhibitors have shown disappointing results in clinical trials of solid tumors, therapeutic targets specific to HDAC3 function represent a promising option for differentiation therapy in malignant tumors with dysregulated HDAC3 activity. PMID:27956629

CRISPR screen identifies the NCOR/HDAC3 complex as a major suppressor of differentiation in rhabdomyosarcoma.

PubMed

Phelps, Michael P; Bailey, Jenna N; Vleeshouwer-Neumann, Terra; Chen, Eleanor Y

2016-12-27

Dysregulated gene expression resulting from abnormal epigenetic alterations including histone acetylation and deacetylation has been demonstrated to play an important role in driving tumor growth and progression. However, the mechanisms by which specific histone deacetylases (HDACs) regulate differentiation in solid tumors remains unclear. Using pediatric rhabdomyosarcoma (RMS) as a paradigm to elucidate the mechanism blocking differentiation in solid tumors, we identified HDAC3 as a major suppressor of myogenic differentiation from a high-efficiency Clustered regularly interspaced short palindromic repeats (CRISPR)-based phenotypic screen of class I and II HDAC genes. Detailed characterization of the HDAC3-knockout phenotype in vitro and in vivo using a tamoxifen-inducible CRISPR targeting strategy demonstrated that HDAC3 deacetylase activity and the formation of a functional complex with nuclear receptor corepressors (NCORs) were critical in restricting differentiation in RMS. The NCOR/HDAC3 complex specifically functions by blocking myoblast determination protein 1 (MYOD1)-mediated activation of myogenic differentiation. Interestingly, there was also a transient up-regulation of growth-promoting genes upon initial HDAC3 targeting, revealing a unique cancer-specific response to the forced transition from a neoplastic state to terminal differentiation. Our study applied modifications of CRISPR/CRISPR-associated endonuclease 9 (Cas9) technology to interrogate the function of essential cancer genes and pathways and has provided insights into cancer cell adaptation in response to altered differentiation status. Because current pan-HDAC inhibitors have shown disappointing results in clinical trials of solid tumors, therapeutic targets specific to HDAC3 function represent a promising option for differentiation therapy in malignant tumors with dysregulated HDAC3 activity.

Determination of Heritage SSME Pogo Suppressor Resistance and Inertance from Waterflow Pulse Testing

NASA Technical Reports Server (NTRS)

McDougal, Chris; Eberhart, Chad; Lee, Erik

2016-01-01

Waterflow tests of a heritage Space Shuttle Main Engine pogo suppressor were performed to experimentally quantify the resistance and inertance provided by the suppressor. Measurements of dynamic pressure and flow rate in response to pulsing flow were made throughout the test loop. A unique system identification methodology combined all sensor measurements with a one-dimensional perturbational flow model of the complete water flow loop to spatially translate physical measurements to the device under test. Multiple techniques were then employed to extract the effective resistance and inertance for the pogo suppressor. Parameters such as steady flow rate, perturbational flow rate magnitude, and pulse frequency were investigated to assess their influence on the behavior of the pogo suppressor dynamic response. These results support validation of the RS-25 pogo suppressor performance for use on the Space Launch System Core Stage.

Inflammatory peroxidases promote breast cancer progression in mice via regulation of the tumour microenvironment.

PubMed

Panagopoulos, Vasilios; Leach, Damien A; Zinonos, Irene; Ponomarev, Vladimir; Licari, Giovanni; Liapis, Vasilios; Ingman, Wendy V; Anderson, Peter; DeNichilo, Mark O; Evdokiou, Andreas

2017-04-01

Myeloperoxidase (MPO) and eosinophil peroxidase (EPO) are heme-containing enzymes, well known for their antimicrobial activity, are released in high quantities by infiltrating immune cells in breast cancer. However, the functional importance of their presence within the tumour microenvironment is unclear. We have recently described a new role for peroxidases as key regulators of fibroblast and endothelial cell functionality. In the present study, we investigate for the first time, the ability of peroxidases to promote breast cancer development and progression. Using the 4T1 syngeneic murine orthotopic breast cancer model, we examined whether increased levels of peroxidases in developing mammary tumours influences primary tumour growth and metastasis. We showed that MPO and EPO stimulation increased mammary tumour growth and enhanced lung metastases, effects that were associated with reduced tumour necrosis, increased collagen deposition and neo-vascularisation within the primary tumour. In vitro, peroxidase treatment, robustly stimulated human mammary fibroblast migration and collagen type I and type VI secretion. Mechanistically, peroxidases induced the transcription of pro-tumorigenic and metastatic MMP1, MMP3 and COX-2 genes. Taken together, these findings identify peroxidases as key contributors to cancer progression by augmenting pro-tumorigenic collagen production and angiogenesis. Importantly, this identifies inflammatory peroxidases as therapeutic targets in breast cancer therapy.

Firearm suppressor having enhanced thermal management for rapid heat dissipation

DOEpatents

Moss, William C.; Anderson, Andrew T.

2014-08-19

A suppressor is disclosed for use with a weapon having a barrel through which a bullet is fired. The suppressor has an inner portion having a bore extending coaxially therethrough. The inner portion is adapted to be secured to a distal end of the barrel. A plurality of axial flow segments project radially from the inner portion and form axial flow paths through which expanding propellant gasses discharged from the barrel flow through. The axial flow segments have radially extending wall portions that define sections which may be filled with thermally conductive material, which in one example is a thermally conductive foam. The conductive foam helps to dissipate heat deposited within the suppressor during firing of the weapon.

Bilateral multifocal Warthin tumours.

PubMed

Deveer, Mehmet; Sahan, Murat; Sivrioglu, Ali Kemal; Celik, Ozgür Ilhan

2013-05-22

Warthin tumour, also known as papillary cystadenoma lymphomatosum, is the second most frequent benign tumour of the parotid gland after pleomorphic adenoma. A 57-year-old man was referred to our hospital with bilateral buccal masses without pain. He presented with a 1-year history of the condition and stated that growth of the mass has accelerated during the last 6 months. Ultrasonography examination showed two heterogeneous solid masses. Axial contrast-enhanced CT image revealed bilateral heterogeneous solid masses. The masses showed enhancement after contrast administration (95 HU). Fine needle aspiration cytology was recommended for further analysis and typical benign features of Warthin tumour was obtained. Right parotid gland including the masses was resected completely. 5 weeks later superficial parotidectomy was performed to the left parotid gland. Histological examination revealed cystic tumour in the parenchyma of parotid gland, composed of prominent lymphoid stroma and large epithelial cells with oncocytic features covering it consistent with Warthin tumour.

Bilateral multifocal Warthin tumours

PubMed Central

Deveer, Mehmet; Sahan, Murat; Sivrioglu, Ali Kemal; İlhan Celik, Özgür

2013-01-01

Warthin tumour, also known as papillary cystadenoma lymphomatosum, is the second most frequent benign tumour of the parotid gland after pleomorphic adenoma. A 57-year-old man was referred to our hospital with bilateral buccal masses without pain. He presented with a 1-year history of the condition and stated that growth of the mass has accelerated during the last 6 months. Ultrasonography examination showed two heterogeneous solid masses. Axial contrast-enhanced CT image revealed bilateral heterogeneous solid masses. The masses showed enhancement after contrast administration (95 HU). Fine needle aspiration cytology was recommended for further analysis and typical benign features of Warthin tumour was obtained. Right parotid gland including the masses was resected completely. 5 weeks later superficial parotidectomy was performed to the left parotid gland. Histological examination revealed cystic tumour in the parenchyma of parotid gland, composed of prominent lymphoid stroma and large epithelial cells with oncocytic features covering it consistent with Warthin tumour. PMID:23704438

Molecular crosstalk between tumour and brain parenchyma instructs histopathological features in glioblastoma

PubMed Central

Bougnaud, Sébastien; Golebiewska, Anna; Oudin, Anaïs; Keunen, Olivier; Harter, Patrick N.; Mäder, Lisa; Azuaje, Francisco; Fritah, Sabrina; Stieber, Daniel; Kaoma, Tony; Vallar, Laurent; Brons, Nicolaas H.C.; Daubon, Thomas; Miletic, Hrvoje; Sundstrøm, Terje; Herold-Mende, Christel; Mittelbronn, Michel; Bjerkvig, Rolf; Niclou, Simone P.

2016-01-01

The histopathological and molecular heterogeneity of glioblastomas represents a major obstacle for effective therapies. Glioblastomas do not develop autonomously, but evolve in a unique environment that adapts to the growing tumour mass and contributes to the malignancy of these neoplasms. Here, we show that patient-derived glioblastoma xenografts generated in the mouse brain from organotypic spheroids reproducibly give rise to three different histological phenotypes: (i) a highly invasive phenotype with an apparent normal brain vasculature, (ii) a highly angiogenic phenotype displaying microvascular proliferation and necrosis and (iii) an intermediate phenotype combining features of invasion and vessel abnormalities. These phenotypic differences were visible during early phases of tumour development suggesting an early instructive role of tumour cells on the brain parenchyma. Conversely, we found that tumour-instructed stromal cells differentially influenced tumour cell proliferation and migration in vitro, indicating a reciprocal crosstalk between neoplastic and non-neoplastic cells. We did not detect any transdifferentiation of tumour cells into endothelial cells. Cell type-specific transcriptomic analysis of tumour and endothelial cells revealed a strong phenotype-specific molecular conversion between the two cell types, suggesting co-evolution of tumour and endothelial cells. Integrative bioinformatic analysis confirmed the reciprocal crosstalk between tumour and microenvironment and suggested a key role for TGFβ1 and extracellular matrix proteins as major interaction modules that shape glioblastoma progression. These data provide novel insight into tumour-host interactions and identify novel stroma-specific targets that may play a role in combinatorial treatment strategies against glioblastoma. PMID:27049916

Ciliated muconodular papillary tumour of the lung: a newly defined low-grade malignant tumour.

PubMed

Sato, Shuichi; Koike, Teruaki; Homma, Keiichi; Yokoyama, Akira

2010-11-01

We present two cases of ciliated muconodular papillary tumour (CMPT) in this report. CMPT is a newly defined low-grade malignant tumour with ciliated columnar epithelial cells, occurring in the peripheral lung. Both patients underwent pulmonary resection due to an enlarged solitary pulmonary nodule. Pathological findings in both cases confirmed a papillary tumour with a mixture of ciliated columnar and goblet cells. The tumours were rich in mucous and had spread along the alveolar walls, as observed in bronchioloalveolar carcinoma. Nuclear atypia was mild, and no mitotic activity was observed. Immunohistochemically, tumour cells stained positive for carcinoembryonic antigen, thyroid transcription factor-1 and cytokeratin 7 but not for cytokeratin 20. The immunohistochemical staining patterns were almost identical to those of pulmonary adenocarcinoma. We definitively diagnosed as CMPT. Both patients remained relapse-free.

Reciprocal relationship of T regulatory cells and monocytic myeloid-derived suppressor cells in LP-BM5 murine retrovirus-induced immunodeficiency.

PubMed

O'Connor, Megan A; Vella, Jennifer L; Green, William R

2016-02-01

Immunomodulatory cellular subsets, including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (Tregs), contribute to the immunosuppressive tumour microenvironment and are targets of immunotherapy, but their role in retroviral-associated immunosuppression is less well understood. Due to known crosstalk between Tregs and MDSCs in the tumour microenvironment, and also their hypothesized involvement during human immunodeficiency virus/simian immunodeficiency virus infection, studying the interplay between these immune cells during LP-BM5 retrovirus-induced murine AIDS is of interest. IL-10-producing FoxP3+ Tregs expanded after LP-BM5 infection. Following in vivo adoptive transfer of natural Treg (nTreg)-depleted CD4+T-cells, and subsequent LP-BM5 retroviral infection, enriched monocytic MDSCs (M-MDSCs) from these nTreg-depleted mice displayed altered phenotypic subsets. In addition, M-MDSCs from LP-BM5-infected nTreg-depleted mice exhibited increased suppression of T-cell, but not B-cell, responses, compared with M-MDSCs derived from non-depleted LP-BM5-infected controls. Additionally, LP-BM5-induced M-MDSCs modulated the production of IL-10 by FoxP3+ Tregs in vitro. These collective data highlight in vitro and for the first time, to the best of our knowledge, in vivo reciprocal modulation between retroviral-induced M-MDSCs and Tregs, and may provide insight into the immunotherapeutic targeting of such regulatory cells during retroviral infection.

Tumour seeding after percutaneous cryoablation for hepatocellular carcinoma

PubMed Central

Wang, Chun-Ping; Wang, Hong; Qu, Jian-Hui; Lu, Yin-Ying; Bai, Wen-Lin; Dong, Zheng; Gao, Xu-Dong; Rong, Guang-Hua; Zeng, Zhen; Yang, Yong-Ping

2012-01-01

AIM: To assess the rate and risk factors for tumour seeding in a large cohort of patients. METHODS: Over an 8-year period, 1436 hepatocellular carcinoma (HCC) patients with 2423 tumour nodules underwent 3015 image-guided percutaneous cryoablation sessions [1215 guided by ultrasonography and 221 by spiral computed tomography (CT)]. Follow-up CT or magnetic resonance imaging was performed every 3 mo. The detailed clinical data were recorded to analyse the risk factors for seeding. RESULTS: The median follow-up time was 18 (range 1-90) mo. Seeding was detected in 11 patients (0.76%) at 1-24 (median 6.0) mo after cryoablation. Seeding occurred along the needle tract in 10 patients and at a distant location in 1 patient. Seeded tumours usually showed similar imaging and histopathological features to the primary HCCs. Univariate analyses identified subcapsular tumour location and direct subcapsular needle insertion as risk factors for seeding. Multivariate analysis showed that only direct subcapsular needle insertion was an independent risk factor for seeding (P = 0.017; odds ratio 2.57; 95%CI: 1.47-3.65). Seeding after cryoablation occurred earlier in patients with poorly differentiated HCC than those with well or moderately differentiated HCC [1.33 ± 0.577 mo vs 11.12 ± 6.896 mo; P = 0.042; 95%CI: (-19.115)-(-0.468)]. CONCLUSION: The risk of seeding after cryoablation for HCC is small. Direct puncture of subcapsular tumours should be avoided to minimise seeding. PMID:23236233

DNA methylation profiling of phyllodes and fibroadenoma tumours of the breast.

PubMed

Huang, Katie T; Dobrovic, Alexander; Yan, Max; Karim, Rooshdiya Z; Lee, C Soon; Lakhani, Sunil R; Fox, Stephen B

2010-11-01

Phyllodes tumours and cellular fibroadenomas are both fibroepithelial tumours of the breast. Phyllodes tumours, unlike fibroadenomas, have the ability to recur and metastasise. Although these lesions can be distinguished by their stromal cellularity, mitotic index, presence or absence of stromal overgrowth and cellular atypia, there is overlap and not infrequently a definitive diagnosis cannot be made, particularly on biopsy. We sought to evaluate whether DNA promoter methylation profiling using selected genes known to be methylated in cancer would allow us to learn more about the biology of these tumours, and whether it could identify methylation markers that could differentiate phyllodes tumours from fibroadenomas and/or distinguish phyllodes tumours of different grades. Methylation-sensitive high resolution melting (MS-HRM) was used to screen promoter DNA methylation changes in 86 phyllodes tumours (15 benign, 28 borderline, 43 malignant) and 26 fibroadenomas. A panel of 11 genes (RASSF1A, TWIST1, APC, WIF1, MGMT, MAL, RARβ, CDKN2A, CDH1, TP73 and MLH1) was tested. Methylation status was correlated with histology and with clinicopathological parameters. Five of the gene promoters showed some methylation in a proportion of phyllodes tumours; RASSF1A, 45.3%; TWIST1, 10.7%; APC, 4.1%; WIF1, 2.9% and MGMT, 1.3%. Only two genes showed any methylation in fibroadenomas usually at background levels; RASSF1A, 53.8% and MGMT, 8.3%. No CDKN2A methylation was observed in either tumour type, contrary to previous reports. Overall, the methylation patterns differed little from that which might be seen in normal cells. However, significant levels of methylation of RASSF1A (24.4%) and TWIST1 (7.1%) was observed in some phyllodes tumours. Elevated RASSF1A and/or TWIST1 methylation was significantly associated with phyllodes tumours compared with fibroadenomas (P = 0.02), TWIST1 methylation correlated with increasing malignancy in phyllodes tumours (P < 0.001). In conclusion

Multidisciplinary team working across different tumour types: analysis of a national survey.

PubMed

Lamb, B W; Sevdalis, N; Taylor, C; Vincent, C; Green, J S A

2012-05-01

Using data from a national survey, this study aimed to address whether the current model for multidisciplinary team (MDT) working is appropriate for all tumour types. Responses to the 2009 National Cancer Action Team national survey were analysed by tumour type. Differences indicate lack of consensus between MDT members in different tumour types. One thousand one hundred and forty-one respondents from breast, gynaecological, colorectal, upper gastrointestinal, urological, head and neck, haematological and lung MDTs were included. One hundred and sixteen of 136 statements demonstrated consensus between respondents in different tumour types. There were no differences regarding the infrastructure for meetings and team governance. Significant consensus was seen for team characteristics, and respondents disagreed regarding certain aspects of meeting organisations and logistics, and patient-centred decision making. Haematology MDT members were outliers in relation to the clinical decision-making process, and lung MDT members disagreed with other tumour types regarding treating patients with advanced disease. This analysis reveals strong consensus between MDT members from different tumour types, while also identifying areas that require a more tailored approach, such as the clinical decision-making process, and preparation for and the organisation of MDT meetings. Policymakers should remain sensitive to the needs of health care teams working in individual tumour types.

Three distinct suppressors of RNA silencing encoded by a 20-kb viral RNA genome

NASA Astrophysics Data System (ADS)

Lu, Rui; Folimonov, Alexey; Shintaku, Michael; Li, Wan-Xiang; Falk, Bryce W.; Dawson, William O.; Ding, Shou-Wei

2004-11-01

Viral infection in both plant and invertebrate hosts requires a virus-encoded function to block the RNA silencing antiviral defense. Here, we report the identification and characterization of three distinct suppressors of RNA silencing encoded by the 20-kb plus-strand RNA genome of citrus tristeza virus (CTV). When introduced by genetic crosses into plants carrying a silencing transgene, both p20 and p23, but not coat protein (CP), restored expression of the transgene. Although none of the CTV proteins prevented DNA methylation of the transgene, export of the silencing signal (capable of mediating intercellular silencing spread) was detected only from the F1 plants expressing p23 and not from the CP- or p20-expressing F1 plants, demonstrating suppression of intercellular silencing by CP and p20 but not by p23. Thus, intracellular and intercellular silencing are each targeted by a CTV protein, whereas the third, p20, inhibits silencing at both levels. Notably, CP suppresses intercellular silencing without interfering with intracellular silencing. The novel property of CP suggests a mechanism distinct to p20 and all of the other viral suppressors known to interfere with intercellular silencing and that this class of viral suppressors may not be consistently identified by Agrobacterium coinfiltration because it also induces RNA silencing against the infiltrated suppressor transgene. Our analyses reveal a sophisticated viral counter-defense strategy that targets the silencing antiviral pathway at multiple steps and may be essential for protecting CTV with such a large RNA genome from antiviral silencing in the perennial tree host. RNA interference | citrus tristeza virus | virus synergy | antiviral immunity

Cell-free circulating tumour DNA as a liquid biopsy in breast cancer.

PubMed

De Mattos-Arruda, Leticia; Caldas, Carlos

2016-03-01

Recent developments in massively parallel sequencing and digital genomic techniques support the clinical validity of cell-free circulating tumour DNA (ctDNA) as a 'liquid biopsy' in human cancer. In breast cancer, ctDNA detected in plasma can be used to non-invasively scan tumour genomes and quantify tumour burden. The applications for ctDNA in plasma include identifying actionable genomic alterations, monitoring treatment responses, unravelling therapeutic resistance, and potentially detecting disease progression before clinical and radiological confirmation. ctDNA may be used to characterise tumour heterogeneity and metastasis-specific mutations providing information to adapt the therapeutic management of patients. In this article, we review the current status of ctDNA as a 'liquid biopsy' in breast cancer. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Flow cytometric techniques for detection of candidate cancer stem cell subpopulations in canine tumour models.

PubMed

Blacking, T M; Waterfall, M; Samuel, K; Argyle, D J

2012-12-01

The cancer stem cell (CSC) hypothesis proposes that tumour growth is maintained by a distinct subpopulation of 'CSC'. This study applied flow cytometric methods, reported to detect CSC in both primary and cultured cancer cells of other species, to identify candidate canine subpopulations. Cell lines representing diverse canine malignancies, and cells derived from spontaneous canine tumours, were evaluated for expression of stem cell-associated surface markers (CD34, CD44, CD117 and CD133) and functional properties [Hoecsht 33342 efflux, aldehyde dehydrogenase (ALDH) activity]. No discrete marker-defined subsets were identified within established cell lines; cells derived directly from spontaneous tumours demonstrated more heterogeneity, although this diminished upon in vitro culture. Functional assays produced variable results, suggesting context-dependency. Flow cytometric methods may be adopted to identify putative canine CSC. Whilst cell lines are valuable in assay development, primary cells may provide a more rewarding model for studying tumour heterogeneity in the context of CSC. However, it will be essential to fully characterize any candidate subpopulations to ensure that they meet CSC criteria. © 2011 Blackwell Publishing Ltd.

Suppressor Mutation Analysis of the Sensory Rhodopsin I-Transducer Complex: Insights into the Color-Sensing Mechanism

PubMed Central

Jung, Kwang-Hwan; Spudich, John L.

1998-01-01

The molecular complex containing the phototaxis receptor sensory rhodopsin I (SRI) and transducer protein HtrI (halobacterial transducer for SRI) mediates color-sensitive phototaxis responses in the archaeon Halobacterium salinarum. One-photon excitation of the complex by orange light elicits attractant responses, while two-photon excitation (orange followed by near-UV light) elicits repellent responses in swimming cells. Several mutations in SRI and HtrI cause an unusual mutant phenotype, called orange-light-inverted signaling, in which the cell produces a repellent response to normally attractant light. We applied a selection procedure for intragenic and extragenic suppressors of orange-light-inverted mutants and identified 15 distinct second-site mutations that restore the attractant response. Two of the 3 suppressor mutations in SRI are positioned at the cytoplasmic ends of helices F and G, and 12 suppressor mutations in HtrI cluster at the cytoplasmic end of the second HtrI transmembrane helix (TM2). Nearly all suppressors invert the normally repellent response to two-photon stimulation to an attractant response when they are expressed with their suppressible mutant alleles or in an otherwise wild-type strain. The results lead to a model for control of flagellar reversal by the SRI-HtrI complex. The model invokes an equilibrium between the A (reversal-inhibiting) and R (reversal-stimulating) conformers of the signaling complex. Attractant light and repellent light shift the equilibrium toward the A and R conformers, respectively, and mutations are proposed to cause intrinsic shifts in the equilibrium in the dark form of the complex. Differences in the strength of the two-photon signal inversion and in the allele specificity of suppression are correlated, and this correlation can be explained in terms of different values of the equilibrium constant (Keq) for the conformational transition in different mutants and mutant-suppressor pairs. PMID:9555883

Primary osseous tumours of the elbow: 60 years of registry experience

PubMed Central

Halai, Mansur; Gupta, Sanjay; Wallace, David; Rymaszewski, Lech; Mahendra, Ashish

2015-01-01

Background We present the largest series of surgically treated primary bone tumours of the elbow in the English literature (75 cases). We sought to identify characteristics specific to these lesions and recommend an investigatory protocol. Methods The national registry and case notes were reviewed between 1954-2014. Tumours were classified according to Enneking's spectrum. Results There were no benign latent cases in this series as these were managed locally. All patients presented with persistent rest pain, with or without swelling. The distal humerus, in contrast to the proximal radius and ulna, was responsible for the majority and the more aggressive cases. Misdiagnosis was evident in 13% of cases; most of which were attributed to simple bone cysts. All patients that were referred required surgical intervention to either establish the diagnosis or for treatment. Benign tumours had a 19% recurrence rate, with giant cell tumour the most aggressive. Malignant tumours carried 39% local recurrence rate and a 5-year mortality of 61%. Conclusions The suspicion of a tumour should be raised in the patient with unremitting, unexplained, non-mechanical bony elbow pain. These echo the NICE recommendations and we recommend prompt specialist referral. With high rates of local recurrence, we recommend close postoperative monitoring. PMID:27582988

Breast tumour visualization using 3D quantitative ultrasound methods

NASA Astrophysics Data System (ADS)

Gangeh, Mehrdad J.; Raheem, Abdul; Tadayyon, Hadi; Liu, Simon; Hadizad, Farnoosh; Czarnota, Gregory J.

2016-04-01

Breast cancer is one of the most common cancer types accounting for 29% of all cancer cases. Early detection and treatment has a crucial impact on improving the survival of affected patients. Ultrasound (US) is non-ionizing, portable, inexpensive, and real-time imaging modality for screening and quantifying breast cancer. Due to these attractive attributes, the last decade has witnessed many studies on using quantitative ultrasound (QUS) methods in tissue characterization. However, these studies have mainly been limited to 2-D QUS methods using hand-held US (HHUS) scanners. With the availability of automated breast ultrasound (ABUS) technology, this study is the first to develop 3-D QUS methods for the ABUS visualization of breast tumours. Using an ABUS system, unlike the manual 2-D HHUS device, the whole patient's breast was scanned in an automated manner. The acquired frames were subsequently examined and a region of interest (ROI) was selected in each frame where tumour was identified. Standard 2-D QUS methods were used to compute spectral and backscatter coefficient (BSC) parametric maps on the selected ROIs. Next, the computed 2-D parameters were mapped to a Cartesian 3-D space, interpolated, and rendered to provide a transparent color-coded visualization of the entire breast tumour. Such 3-D visualization can potentially be used for further analysis of the breast tumours in terms of their size and extension. Moreover, the 3-D volumetric scans can be used for tissue characterization and the categorization of breast tumours as benign or malignant by quantifying the computed parametric maps over the whole tumour volume.

Antiangiogenic and tumour inhibitory effects of downregulating tumour endothelial FABP4

PubMed Central

Harjes, U; Bridges, E; Gharpure, K M; Roxanis, I; Sheldon, H; Miranda, F; Mangala, L S; Pradeep, S; Lopez-Berestein, G; Ahmed, A; Fielding, B; Sood, A K; Harris, A L

2017-01-01

Fatty acid binding protein 4 (FABP4) is a fatty acid chaperone, which is induced during adipocyte differentiation. Previously we have shown that FABP4 in endothelial cells is induced by the NOTCH1 signalling pathway, the latter of which is involved in mechanisms of resistance to antiangiogenic tumour therapy. Here, we investigated the role of FABP4 in endothelial fatty acid metabolism and tumour angiogenesis. We analysed the effect of transient FABP4 knockdown in human umbilical vein endothelial cells on fatty acid metabolism, viability and angiogenesis. Through therapeutic delivery of siRNA targeting mouse FABP4, we investigated the effect of endothelial FABP4 knockdown on tumour growth and blood vessel formation. In vitro, siRNA-mediated FABP4 knockdown in endothelial cells led to a marked increase of endothelial fatty acid oxidation, an increase of reactive oxygen species and decreased angiogenesis. In vivo, we found that increased NOTCH1 signalling in tumour xenografts led to increased expression of endothelial FABP4 that decreased when NOTCH1 and VEGFA inhibitors were used in combination. Angiogenesis, growth and metastasis in ovarian tumour xenografts were markedly inhibited by therapeutic siRNA delivery targeting mouse endothelial FABP4. Therapeutic targeting of endothelial FABP4 by siRNA in vivo has antiangiogenic and antitumour effects with minimal toxicity and should be investigated further. PMID:27568980

Antiangiogenic and tumour inhibitory effects of downregulating tumour endothelial FABP4.

PubMed

Harjes, U; Bridges, E; Gharpure, K M; Roxanis, I; Sheldon, H; Miranda, F; Mangala, L S; Pradeep, S; Lopez-Berestein, G; Ahmed, A; Fielding, B; Sood, A K; Harris, A L

2017-02-16

Fatty acid binding protein 4 (FABP4) is a fatty acid chaperone, which is induced during adipocyte differentiation. Previously we have shown that FABP4 in endothelial cells is induced by the NOTCH1 signalling pathway, the latter of which is involved in mechanisms of resistance to antiangiogenic tumour therapy. Here, we investigated the role of FABP4 in endothelial fatty acid metabolism and tumour angiogenesis. We analysed the effect of transient FABP4 knockdown in human umbilical vein endothelial cells on fatty acid metabolism, viability and angiogenesis. Through therapeutic delivery of siRNA targeting mouse FABP4, we investigated the effect of endothelial FABP4 knockdown on tumour growth and blood vessel formation. In vitro, siRNA-mediated FABP4 knockdown in endothelial cells led to a marked increase of endothelial fatty acid oxidation, an increase of reactive oxygen species and decreased angiogenesis. In vivo, we found that increased NOTCH1 signalling in tumour xenografts led to increased expression of endothelial FABP4 that decreased when NOTCH1 and VEGFA inhibitors were used in combination. Angiogenesis, growth and metastasis in ovarian tumour xenografts were markedly inhibited by therapeutic siRNA delivery targeting mouse endothelial FABP4. Therapeutic targeting of endothelial FABP4 by siRNA in vivo has antiangiogenic and antitumour effects with minimal toxicity and should be investigated further.

Tumours of the upper alimentary tract

PubMed Central

Head, K. W.

1976-01-01

Tumours of the oropharynx of domestic animals are common in most parts of the world, but squamous cell carcinoma of the upper alimentary tract shows differences in prevalence in different geographical areas and occurs at different sites in the various species. Oral tumours of the melanogenic system are more common in dogs than in man. The following main histological categories, which broadly correspond to those used in the classification of tumours of man, are described: papilloma; squamous cell carcinoma; salivary gland tumours; malignant melanoma; tumours of soft (mesenchymal) tissues; tumours of the facial bones; tumours of haematopoietic and related tissues; and odontogenic tumours and jaw cysts. Papilloma, squamous cell carcinoma, malignant melanoma, fibroma, and fibrosarcoma account for about 80% of the tumours that occur in the upper alimentary tract of domestic animals. ImagesFig. 6Fig. 7Fig. 8Fig. 9Fig. 34Fig. 35Fig. 36Fig. 37Fig. 2Fig. 3Fig. 4Fig. 5Fig. 22Fig. 23Fig. 24Fig. 25Fig. 26Fig. 27Fig. 28Fig. 29Fig. 14Fig. 15Fig. 16Fig. 17Fig. 30Fig. 31Fig. 32Fig. 33Fig. 18Fig. 19Fig. 20Fig. 21Fig. 10Fig. 11Fig. 12Fig. 13Fig. 1 PMID:1086147

Can cell kinetic parameters predict the response of tumours to radiotherapy?

PubMed

McNally, N J

1989-11-01

Three potential predictive assays of the repopulation component in tumour response to therapy are considered. (1) The DNA index can easily be measured. It is of prognostic value for cancers of certain sites, aneuploidy being a bad prognostic indicator. It is not strictly an indicator of cell proliferation. (2) The in vitro labelling index is of predictive value in early stage operable breast cancer and in head and neck cancer. In the former a high pretreatment labelling index can identify patients who could benefit from adjuvant chemotherapy. (3) The tumour potential doubling time (Tpot) can be measured rapidly following in vivo labelling with bromodeoxyuridine or iododeoxyuridine. We have measured Tpot in over 100 solid tumours with a success rate of about 75 per cent. Nearly 50 per cent of the tumours have a pre-treatment potential doubling time of 5 days or less. These would be suitable candidates for accelerated fractionation.

Canonical WNT signalling determines lineage specificity in Wilms tumour.

PubMed

Fukuzawa, R; Anaka, M R; Weeks, R J; Morison, I M; Reeve, A E

2009-02-26

Wilms tumours (WTs) have two distinct types of histology with or without ectopic mesenchymal elements, suggesting that WTs arise from either the mesenchymal or epithelial nephrogenic lineages. Regardless of the presence or absence of CTNNB1 mutations, nuclear accumulation of beta-catenin is often observed in WTs with ectopic mesenchymal elements. Here, we addressed the relationship between the WNT-signalling pathway and lineage in WTs by examining CTNNB1 and WT1 mutations, nuclear accumulation of beta-catenin, tumour histology and gene expression profiles. In addition, we screened for mutations in WTX, which has been proposed to be a negative regulator of the canonical WNT-signalling pathway. Unsupervised clustering analysis identified two classes of tumours: mesenchymal lineage WNT-dependent tumours, and epithelial lineage WNT-independent tumours. In contrast to the mesenchymal lineage specificity of CTNNB1 mutations, WTX mutations were surprisingly observed in both lineages. WTX-mutant WTs with ectopic mesenchymal elements had nuclear accumulation of beta-catenin, upregulation of WNT target genes and an association with CTNNB1 mutations in exon 7 or 8. However, epithelial lineage WTs with WTX mutations had no indications of active WNT signalling, suggesting that the involvement of WTX in the WNT-signalling pathway may be lineage dependent, and that WTX may have an alternative function to its role in the canonical WNT-signalling pathway.

Raf Kinase Inhibitory Protein (RKIP) as a Metastasis Suppressor: Regulation of Signaling Networks in Cancer

PubMed Central

Yesilkanal, Ali E.; Rosner, Marsha R.

2015-01-01

Cancer is one of the deadliest diseases worldwide, accounting for about 8 million deaths a year. For solid tumors, cancer patients die as a result of the metastatic spread of the tumor to the rest of the body. Therefore, there is a clinical need for understanding the molecular and cellular basis of metastasis, identifying patients whose tumors are more likely to metastasize, and developing effective therapies against metastatic progression. Over the years, Raf kinase inhibitory protein (RKIP) has emerged as a natural suppressor of the metastatic process, constituting a tool for studying metastasis and its clinical outcomes. Here, we review RKIP’s role as a metastasis suppressor and the signaling networks and genes regulated by RKIP in metastatic, triple-negative breast cancer. We also highlight the clinical implications and power of building gene signatures based on RKIP-regulated signaling modules in identifying cancer patients that are at higher risk for metastases. Finally, we highlight the potential of RKIP as a tool for developing new therapeutic strategies in cancer treatment. PMID:25597354

A 22-Year Northern Irish Experience of Carotid Body Tumours

PubMed Central

O'Neill, Stephen; O'Donnell, Mark; Harkin, Denis; Loughrey, Maurice; Lee, Bernard; Blair, Paul

2011-01-01

Objectives Carotid body tumours (CBTs) are rare vascular neoplasms originating in paraganglionic cells of the carotid bifurcation. The aim of this study was to review all patients diagnosed with CBTs in Northern Ireland. Methods A retrospective review was performed of all patients who had CBTs treated at our institutions between 1987 and 2009. Patient demographics, clinical symptomatology, investigative modality, therapeutic intervention, pathological analysis and long-term outcomes were assessed. Results Twenty-nine patients were identified with 33 CBTs and three glomus intravagale tumours (GITs). Six patients had bilateral CBTs (21%), one of whom had a synchronous GIT. Twenty-six patients underwent a total of 30 operative procedures for the resection of 28 CBTs and 3 GITs. Conventional operative treatment included subadventitial tumour excision. A vascular shunt facilitated arterial reconstruction following the removal of seven (23%) tumours and on six of these occasions (19%) continuity was restored with an interposition vein graft. For access the external carotid artery was ligated during the removal of four tumours (13%). Two tumours were considered malignant. No peri-operative mortalities were recorded. Immediate complications included peri-operative stroke secondary to an occluded vein graft (n=1), requirement of tracheostomy (n=2), emergency haematoma drainage (n=2) and transient cranial nerve damage (n=8). Late complications included pseudoaneurysm of vein graft with subsequent stoke (n=1), permanent cranial nerve damage (n=9), Horner’s syndrome (n=1) and an asymptomatic vein graft occlusion (n=1). One patient had tumour recurrence two years post-operatively and died due to pulmonary metastases. Two other patients died of unrelated causes. All other patients remain well with no evidence of tumour recurrence at mean followup of 1801 days (range 159-9208 days). Conclusion Our long-term experience is comparable with other reported case series where surgical

A 22-year Northern Irish experience of carotid body tumours.

PubMed

O'Neill, Stephen; O'Donnell, Mark; Harkin, Denis; Loughrey, Maurice; Lee, Bernard; Blair, Paul

2011-09-01

Carotid body tumours (CBTs) are rare vascular neoplasms originating in paraganglionic cells of the carotid bifurcation. The aim of this study was to review all patients diagnosed with CBTs in Northern Ireland. A retrospective review was performed of all patients who had CBTs treated at our institutions between 1987 and 2009. Patient demographics, clinical symptomatology, investigative modality, therapeutic intervention, pathological analysis and long-term outcomes were assessed. Twenty-nine patients were identified with 33 CBTs and three glomus intravagale tumours (GITs). Six patients had bilateral CBTs (21%), one of whom had a synchronous GIT. Twenty-six patients underwent a total of 30 operative procedures for the resection of 28 CBTs and 3 GITs. Conventional operative treatment included subadventitial tumour excision. A vascular shunt facilitated arterial reconstruction following the removal of seven (23%) tumours and on six of these occasions (19%) continuity was restored with an interposition vein graft. For access the external carotid artery was ligated during the removal of four tumours (13%). Two tumours were considered malignant. No peri-operative mortalities were recorded. Immediate complications included peri-operative stroke secondary to an occluded vein graft (n=1), requirement of tracheostomy (n=2), emergency haematoma drainage (n=2) and transient cranial nerve damage (n=8). Late complications included pseudoaneurysm of vein graft with subsequent stoke (n=1), permanent cranial nerve damage (n=9), Horner's syndrome (n=1) and an asymptomatic vein graft occlusion (n=1). One patient had tumour recurrence two years post-operatively and died due to pulmonary metastases. Two other patients died of unrelated causes. All other patients remain well with no evidence of tumour recurrence at mean followup of 1801 days (range 159-9208 days). Our long-term experience is comparable with other reported case series where surgical intervention conferred a long

Enhancing the performance of gastrointestinal tumour board by improving documentation.

PubMed

Alsuhaibani, Roaa Saleh; Alzahrani, Hajer; Algwaiz, Ghada; Alfarhan, Haneen; Alolayan, Ashwaq; Abdelhafiz, Nafisa; Ali, Yosra; Jazieh, Abdul Rahman

2018-01-01

Tumour board contributes to providing better patient care by using a multidisciplinary team approach. In the efforts of evaluating the performance of the gastrointestinal tumour board at our institution, it was difficult to assess past performance due to lack of proper use of standardised documentation tool. This project aimed at improving adherence to the documentation tool and its recommendations in order to obtain performance measures for the tumour board. A multidisciplinary team and a plan were developed to improve documentation. Four rapid improvement cycles, Plan-Do-Study-Act (PDSA) cycles, were conducted. The first cycle focused on updating the case discussion summary form (CDSF) based on experts' input and previous identified deficiencies to enhance documentation and improve performance. The second PDSA cycle aimed at incorporating the CDSF into the electronic medical records system and assessing its functionality. The third cycle was to orient and train staff on using the form and launching it. The fourth PDSA cycle aimed at assessing the ability to obtain tumour board performance measures. Adherence to completion of the CDSF improved from 82% (baseline) to 94% after the fourth PDSA cycle. Over 104 consecutive cases discussed in the tumour board between January and July 2016 and 76 cases discussed in 2015, results were as follows: adherence to National Comprehensive Cancer Network guidelines in 2016 was observed in 141 (95%) recommendations, while it was observed in 90 (92%) recommendations in 2015. Changes in the management plans were observed in 37 (36%) cases in 2016 and in 6 (8%) cases in 2015. Regarding tumour board recommendations, 87% were done within 3 months of tumour board discussion in 2016, while 69% were done in 2015. Implementing electronic standardised documentation tool improved communication among the team and enabled getting accurate data about performance measures of the tumour board with positive impact on healthcare process and

Enhancing the performance of gastrointestinal tumour board by improving documentation

PubMed Central

Alsuhaibani, Roaa Saleh; Alzahrani, Hajer; Algwaiz, Ghada; Alfarhan, Haneen; Alolayan, Ashwaq; Abdelhafiz, Nafisa; Ali, Yosra; Jazieh, Abdul Rahman

2018-01-01

Tumour board contributes to providing better patient care by using a multidisciplinary team approach. In the efforts of evaluating the performance of the gastrointestinal tumour board at our institution, it was difficult to assess past performance due to lack of proper use of standardised documentation tool. This project aimed at improving adherence to the documentation tool and its recommendations in order to obtain performance measures for the tumour board. A multidisciplinary team and a plan were developed to improve documentation. Four rapid improvement cycles, Plan–Do–Study–Act (PDSA) cycles, were conducted. The first cycle focused on updating the case discussion summary form (CDSF) based on experts’ input and previous identified deficiencies to enhance documentation and improve performance. The second PDSA cycle aimed at incorporating the CDSF into the electronic medical records system and assessing its functionality. The third cycle was to orient and train staff on using the form and launching it. The fourth PDSA cycle aimed at assessing the ability to obtain tumour board performance measures. Adherence to completion of the CDSF improved from 82% (baseline) to 94% after the fourth PDSA cycle. Over 104 consecutive cases discussed in the tumour board between January and July 2016 and 76 cases discussed in 2015, results were as follows: adherence to National Comprehensive Cancer Network guidelines in 2016 was observed in 141 (95%) recommendations, while it was observed in 90 (92%) recommendations in 2015. Changes in the management plans were observed in 37 (36%) cases in 2016 and in 6 (8%) cases in 2015. Regarding tumour board recommendations, 87% were done within 3 months of tumour board discussion in 2016, while 69% were done in 2015. Implementing electronic standardised documentation tool improved communication among the team and enabled getting accurate data about performance measures of the tumour board with positive impact on healthcare process

Metastasis Suppressor Genes: At the Interface Between the Environment and Tumor Cell Growth

PubMed Central

Hurst, Douglas R.; Welch, Danny R.

2013-01-01

The molecular mechanisms and genetic programs required for cancer metastasis are sometimes overlapping, but components are clearly distinct from those promoting growth of a primary tumor. Every sequential, rate-limiting step in the sequence of events leading to metastasis requires coordinated expression of multiple genes, necessary signaling events, and favorable environmental conditions or the ability to escape negative selection pressures. Metastasis suppressors are molecules that inhibit the process of metastasis without preventing growth of the primary tumor. The cellular processes regulated by metastasis suppressors are diverse and function at every step in the metastatic cascade. As we gain knowledge into the molecular mechanisms of metastasis suppressors and cofactors with which they interact, we learn more about the process, including appreciation that some are potential targets for therapy of metastasis, the most lethal aspect of cancer. Until now, metastasis suppressors have been described largely by their function. With greater appreciation of their biochemical mechanisms of action, the importance of context is increasingly recognized especially since tumor cells exist in myriad microenvironments. In this review, we assemble the evidence that selected molecules are indeed suppressors of metastasis, collate the data defining the biochemical mechanisms of action, and glean insights regarding how metastasis suppressors regulate tumor cell communication to–from microenvironments. PMID:21199781

CD34 + tumours of the orbit including solitary fibrous tumours: a six-case series.

PubMed

Jung, Su Kyung; Paik, Ji Sun; Park, Gyeong Sin; Yang, Suk-Woo

2017-04-27

To report six cases of CD34+ fibroblastic mesenchymal tumours, which are uncommon neoplasms in the orbit. Six patients presenting with proptosis and palpable mass who were later diagnosed with fibrous solitary tumours, fibrous histocytoma or haemangiopericytoma in the orbit were included. All patients received radiologic examinations and surgical excision for histopathology and immunohistochemistry examinations. Five patients had no recurrence after a minimum follow-up of 12 months. One patient (case 6) experienced recurrence twice, and had debulking surgeries each time. At present, the patient still has remnant tumour in the orbit, but no growth has been detected during the past two years. The tumour size will be closely monitored. Even though fibroblastic tumours are rarely found in the orbit, they can present as a palpable mass with proptosis. Complete surgical excision is important for long-term prognosis, and immunohistochemical study is helpful for confirming pathologic diagnosis.

Presence of a tumour-inhibiting factor (TIF) in sera from normal but not tumour-bearing mice.

PubMed

Kim, B S; Chin, D K

1980-10-01

Some plasmacytomas produce myeloma proteins with known antibody specificities and the secretion of these proteins by individual tumour cells can be determined using haemolytic plaque assay. After a 3 day culture of mouse plasmacytoma cells in medium containing 10% normal mouse serum, the number of plaques was reduced to less than 10% when compared to that of tumour cells incubated with either foetal calf serum or normal rabbit serum. However, tumour cells incubated with sera from mice bearing TEPC-15, McPC-603, or MOPC-315 plasmacytomas displayed control levels of plaques. The production of plaques paralleled the viability of tumour cells suggesting that the reduction of plaque formation is due to the decreased viable cell number. The tumour-inhibiting activity was recovered from the fraction of apparent molecular weight of 300,000-400,000 after a partial purification using an agarose (A 0.5 M) column. This fraction, however, did not suppress in vitro induction of antibody production. Kinetic experiments using sera obtained sequentially from individual mice receiving either TEPC-15 or MOPC-315 plasmacytomas further indicated that the tumour-inhibiting activity is severely reduced during a 2 week period after tumour inoculation. The inhibition of tumour cells did not appear to be specific since tumour cells of three plasmacytomas (TEPC-15, MOPC-167 and MOPC-315), a mastocytoma (P815) and a lymphoma (EL-4) displayed a similar susceptibility to normal serum.

Tumours of the soft (mesenchymal) tissues.

PubMed

Weiss, E

1974-01-01

This is a classification of tumours of fibrous tissue, fat, muscle, blood and lymph vessels, and mast cells, irrespective of the region of the body in which they arise. Tumours of fibrous tissue are divided into fibroma, fibrosarcoma (including "canine haemangiopericytoma"), other sarcomas, equine sarcoid, and various tumour-like lesions. The histological appearance of the tumours is described and illustrated with photographs.

A Novel NHERF1 Mutation in Human Breast Cancer and Effects on Malignant Progression.

PubMed

Yang, Xiaomei; Du, Guifang; Yu, Zhen; Si, Yang; Martin, Tracey A; He, Junqi; Cheng, Shan; Jiang, Wen G

2017-01-01

Na + /H + exchanger regulatory factor 1 (NHERF1) has been reported to interact with post-synaptic density protein/Drosophila disc large tumour suppressor/zonula occludens 1 protein (PDZ) binding proteins by its two PDZ domains. These associations have effects on cellular signal transductions. NHERF1 has also been indicated as a cancer-related gene in several solid tumour types. We identified a novel mutation (A190D), of the PDZ2 domain of NHERF1 in breast cancer tissues. NHERF1 A190D mutation abolished NHERF1 modulation of proliferation and migration. In this study, we found that NHERF1 A190D mutation increased nuclear localisation of the protein compared to wild-type NHERF1. It has been reported that YES-associated protein (YAP) interacts with NHERF1. Here we found that NHERF1 A190D mutation increased the binding affinity between NHERF1 and YAP, which inhibited the phosphorylation of YAP. These data suggest that wild-type NHERF1 acts as a tumour suppressor, while NHERF1 A190D mutation abolishes the tumour-suppressive effect in cancer cells, due to A190D mutation-mediated nuclear NHERF1 translocation and induction of YAP phosphorylation. Copyright© 2017 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Selective activation of p53-mediated tumour suppression in high-grade tumours.

PubMed

Junttila, Melissa R; Karnezis, Anthony N; Garcia, Daniel; Madriles, Francesc; Kortlever, Roderik M; Rostker, Fanya; Brown Swigart, Lamorna; Pham, David M; Seo, Youngho; Evan, Gerard I; Martins, Carla P

2010-11-25

Non-small cell lung carcinoma (NSCLC) is the leading cause of cancer-related death worldwide, with an overall 5-year survival rate of only 10-15%. Deregulation of the Ras pathway is a frequent hallmark of NSCLC, often through mutations that directly activate Kras. p53 is also frequently inactivated in NSCLC and, because oncogenic Ras can be a potent trigger of p53 (ref. 3), it seems likely that oncogenic Ras signalling has a major and persistent role in driving the selection against p53. Hence, pharmacological restoration of p53 is an appealing therapeutic strategy for treating this disease. Here we model the probable therapeutic impact of p53 restoration in a spontaneously evolving mouse model of NSCLC initiated by sporadic oncogenic activation of endogenous Kras. Surprisingly, p53 restoration failed to induce significant regression of established tumours, although it did result in a significant decrease in the relative proportion of high-grade tumours. This is due to selective activation of p53 only in the more aggressive tumour cells within each tumour. Such selective activation of p53 correlates with marked upregulation in Ras signal intensity and induction of the oncogenic signalling sensor p19(ARF)( )(ref. 6). Our data indicate that p53-mediated tumour suppression is triggered only when oncogenic Ras signal flux exceeds a critical threshold. Importantly, the failure of low-level oncogenic Kras to engage p53 reveals inherent limits in the capacity of p53 to restrain early tumour evolution and in the efficacy of therapeutic p53 restoration to eradicate cancers.

Notch signaling: switching an oncogene to a tumor suppressor

PubMed Central

Lobry, Camille; Oh, Philmo; Mansour, Marc R.; Look, A. Thomas

2014-01-01

The Notch signaling pathway is a regulator of self-renewal and differentiation in several tissues and cell types. Notch is a binary cell-fate determinant, and its hyperactivation has been implicated as oncogenic in several cancers including breast cancer and T-cell acute lymphoblastic leukemia (T-ALL). Recently, several studies also unraveled tumor-suppressor roles for Notch signaling in different tissues, including tissues where it was before recognized as an oncogene in specific lineages. Whereas involvement of Notch as an oncogene in several lymphoid malignancies (T-ALL, B-chronic lymphocytic leukemia, splenic marginal zone lymphoma) is well characterized, there is growing evidence involving Notch signaling as a tumor suppressor in myeloid malignancies. It therefore appears that Notch signaling pathway’s oncogenic or tumor-suppressor abilities are highly context dependent. In this review, we summarize and discuss latest advances in the understanding of this dual role in hematopoiesis and the possible consequences for the treatment of hematologic malignancies. PMID:24608975

Peculiarities of hyperlipidaemia in tumour patients.

PubMed Central

Dilman, V. M.; Berstein, L. M.; Ostroumova, M. N.; Tsyrlina, Y. V.; Golubev, A. G.

1981-01-01

The study group included 684 cases: 258 patients with breast carcinoma, 113 males with lung cancer, 42 patients with rectal tumours, 42 patients with stomach tumours, 59 patients with fibroadenomatosis, and 170 healthy subjects of varying age (male and female). A relatively high blood triglyceride level was found in patients with breast, lung, rectal (females), and stomach (female) tumours. The blood concentration of high-density lipoprotein-cholesterol in patients with breast, lung, and stomach (female) tumours was relatively low. The elimination of tumour (breast carcinoma) did not lead to significant changes in lipid metabolism. There was no correlation between degree of lipidaemia and stage of tumour progression except in the cases of rectal cancer. Preliminary results are presented on the tentative classification of hyperlipoproteinaemia in tumour patients, using the lipid concentration threshold values advocated by Carlson et al. (1977); an increased frequency of Type IV hyperlipoproteinaemia proved to be the most characteristic feature of tumour patients. The results are discussed in terms of the concept of the importance of lipid metabolic disturbances, primarily those due to ageing, in the genesis of the syndrome of "cancerophilia" (predisposition to cancer). PMID:7248149

Peculiarities of hyperlipidaemia in tumour patients.

PubMed

Dilman, V M; Berstein, L M; Ostroumova, M N; Tsyrlina, Y V; Golubev, A G

1981-05-01

The study group included 684 cases: 258 patients with breast carcinoma, 113 males with lung cancer, 42 patients with rectal tumours, 42 patients with stomach tumours, 59 patients with fibroadenomatosis, and 170 healthy subjects of varying age (male and female). A relatively high blood triglyceride level was found in patients with breast, lung, rectal (females), and stomach (female) tumours. The blood concentration of high-density lipoprotein-cholesterol in patients with breast, lung, and stomach (female) tumours was relatively low. The elimination of tumour (breast carcinoma) did not lead to significant changes in lipid metabolism. There was no correlation between degree of lipidaemia and stage of tumour progression except in the cases of rectal cancer. Preliminary results are presented on the tentative classification of hyperlipoproteinaemia in tumour patients, using the lipid concentration threshold values advocated by Carlson et al. (1977); an increased frequency of Type IV hyperlipoproteinaemia proved to be the most characteristic feature of tumour patients. The results are discussed in terms of the concept of the importance of lipid metabolic disturbances, primarily those due to ageing, in the genesis of the syndrome of "cancerophilia" (predisposition to cancer).

Metastasising pilar tumour of scalp.

PubMed Central

Batman, P A; Evans, H J

1986-01-01

A case of pilar tumour of the scalp, treated by local excision and radiotherapy, later metastasised to the neck. The variable histological growth patterns of the primary tumour and its metastases are described. It is concluded that the pilar tumour is a genuine neoplasm of the hair follicle that is occasionally capable of malignant behaviour. Images PMID:3734112

Mouse mammary tumour virus (MMTV) and human breast cancer with neuroendocrine differentiation.

PubMed

Js, Lawson; Cc, Ngan; Wk, Glenn; Dd, Tran

2017-01-01

Mouse mammary tumour viruses (MMTVs) may have a role in a subset of human breast cancers. MMTV positive human breast cancers have similar histological characteristics to neuroendocrine breast cancers and to MMTV positive mouse mammary tumours. The purpose of this study was to investigate the expression of neuroendocrine biomarkers - synaptophysin and chromogranin, to determine if these histological characteristics and biomarker expression were due to the influences of MMTV. Immunohistochemistry analyses to identify synaptophysin and chromogranin were conducted on a series of human breast cancers in which (i) MMTV had been previously identified and had similar histological characteristics to MMTV positive mouse mammary tumours and (ii) MMTV positive mouse mammary tumours. The expression of synaptophysin and chromogranin in MMTV positive mouse mammary tumors were all positive (7 of 7 specimens - 100% positive). The expression of synaptophysin and chromogranin in MMTV positive human breast cancers was much less prevalent (3 of 22 - 14%). There was no expression of synaptophysin and chromogranin in the normal breast tissue control specimens. It is not possible to draw any firm conclusions from these observations. However, despite the small numbers of MMTV positive mouse mammary tumours in this study, the universal expression in these specimens of synaptophysin and chromogranin proteins is striking. This pattern of synaptophysin and chromogranin expression is very different from their expression in MMTV positive human breast cancers. The reason for these differences is not known. The high prevalence of positive expression of synaptophysin and chromogranin in MMTV positive mouse mammary tumours and low expression of synaptophysin and chromogranin in MMTV positive human breast cancers indicates that MMTV is not usually associated with neuroendocrine human breast cancers.

Maximizing tumour exposure to anti-neuropilin-1 antibody requires saturation of non-tumour tissue antigenic sinks in mice

PubMed Central

Bumbaca, Daniela; Xiang, Hong; Boswell, C Andrew; Port, Ruediger E; Stainton, Shannon L; Mundo, Eduardo E; Ulufatu, Sheila; Bagri, Anil; Theil, Frank-Peter; Fielder, Paul J; Khawli, Leslie A; Shen, Ben-Quan

2012-01-01

BACKGROUND AND PURPOSE Neuropilin-1 (NRP1) is a VEGF receptor that is widely expressed in normal tissues and is involved in tumour angiogenesis. MNRP1685A is a rodent and primate cross-binding human monoclonal antibody against NRP1 that exhibits inhibition of tumour growth in NPR1-expressing preclinical models. However, widespread NRP1 expression in normal tissues may affect MNRP1685A tumour uptake. The objective of this study was to assess MNRP1685A biodistribution in tumour-bearing mice to understand the relationships between dose, non-tumour tissue uptake and tumour uptake. EXPERIMENTAL APPROACH Non-tumour-bearing mice were given unlabelled MNRP1685A at 10 mg·kg−1. Tumour-bearing mice were given 111In-labelled MNRP1685A along with increasing amounts of unlabelled antibody. Blood and tissues were collected from all animals to determine drug concentration (unlabelled) or radioactivity level (radiolabelled). Some animals were imaged using single photon emission computed tomography – X-ray computed tomography. KEY RESULTS MNRP1685A displayed faster serum clearance than pertuzumab, indicating that target binding affected MNRP1685A clearance. I.v. administration of 111In-labelled MNRP1685A to tumour-bearing mice yielded minimal radioactivity in the plasma and tumour, but high levels in the lungs and liver. Co-administration of unlabelled MNRP1685A with the radiolabelled antibody was able to competitively block lungs and liver radioactivity uptake in a dose-dependent manner while augmenting plasma and tumour radioactivity levels. CONCLUSIONS AND IMPLICATIONS These results indicate that saturation of non-tumour tissue uptake is required in order to achieve tumour uptake and acceptable exposure to antibody. Utilization of a rodent and primate cross-binding antibody allows for translation of these results to clinical settings. PMID:22074316

Maximizing tumour exposure to anti-neuropilin-1 antibody requires saturation of non-tumour tissue antigenic sinks in mice.

PubMed

Bumbaca, Daniela; Xiang, Hong; Boswell, C Andrew; Port, Ruediger E; Stainton, Shannon L; Mundo, Eduardo E; Ulufatu, Sheila; Bagri, Anil; Theil, Frank-Peter; Fielder, Paul J; Khawli, Leslie A; Shen, Ben-Quan

2012-05-01

Neuropilin-1 (NRP1) is a VEGF receptor that is widely expressed in normal tissues and is involved in tumour angiogenesis. MNRP1685A is a rodent and primate cross-binding human monoclonal antibody against NRP1 that exhibits inhibition of tumour growth in NPR1-expressing preclinical models. However, widespread NRP1 expression in normal tissues may affect MNRP1685A tumour uptake. The objective of this study was to assess MNRP1685A biodistribution in tumour-bearing mice to understand the relationships between dose, non-tumour tissue uptake and tumour uptake. Non-tumour-bearing mice were given unlabelled MNRP1685A at 10 mg·kg(-1) . Tumour-bearing mice were given (111) In-labelled MNRP1685A along with increasing amounts of unlabelled antibody. Blood and tissues were collected from all animals to determine drug concentration (unlabelled) or radioactivity level (radiolabelled). Some animals were imaged using single photon emission computed tomography - X-ray computed tomography. MNRP1685A displayed faster serum clearance than pertuzumab, indicating that target binding affected MNRP1685A clearance. I.v. administration of (111) In-labelled MNRP1685A to tumour-bearing mice yielded minimal radioactivity in the plasma and tumour, but high levels in the lungs and liver. Co-administration of unlabelled MNRP1685A with the radiolabelled antibody was able to competitively block lungs and liver radioactivity uptake in a dose-dependent manner while augmenting plasma and tumour radioactivity levels. These results indicate that saturation of non-tumour tissue uptake is required in order to achieve tumour uptake and acceptable exposure to antibody. Utilization of a rodent and primate cross-binding antibody allows for translation of these results to clinical settings. © 2011 Genentech Inc. British Journal of Pharmacology © 2011 The British Pharmacological Society.

Modulating glioma-mediated myeloid-derived suppressor cell development with sulforaphane

PubMed Central

Kumar, Ravi; de Mooij, Tristan; Peterson, Timothy E.; Kaptzan, Tatiana; Johnson, Aaron J.; Daniels, David J.; Parney, Ian F.

2017-01-01

Glioblastoma is the most common primary tumor of the brain and has few long-term survivors. The local and systemic immunosuppressive environment created by glioblastoma allows it to evade immunosurveillance. Myeloid-derived suppressor cells (MDSCs) are a critical component of this immunosuppression. Understanding mechanisms of MDSC formation and function are key to developing effective immunotherapies. In this study, we developed a novel model to reliably generate human MDSCs from healthy-donor CD14+ monocytes by culture in human glioma-conditioned media. Monocytic MDSC frequency was assessed by flow cytometry and confocal microscopy. The resulting MDSCs robustly inhibited T cell proliferation. A cytokine array identified multiple components of the GCM potentially contributing to MDSC generation, including Monocyte Chemoattractive Protein-1, interleukin-6, interleukin-8, and Macrophage Migration Inhibitory Factor (MIF). Of these, Macrophage Migration Inhibitory Factor is a particularly attractive therapeutic target as sulforaphane, a naturally occurring MIF inhibitor derived from broccoli sprouts, has excellent oral bioavailability. Sulforaphane inhibits the transformation of normal monocytes to MDSCs by glioma-conditioned media in vitro at pharmacologically relevant concentrations that are non-toxic to normal leukocytes. This is associated with a corresponding increase in mature dendritic cells. Interestingly, sulforaphane treatment had similar pro-inflammatory effects on normal monocytes in fresh media but specifically increased immature dendritic cells. Thus, we have used a simple in vitro model system to identify a novel contributor to glioblastoma immunosuppression for which a natural inhibitor exists that increases mature dendritic cell development at the expense of myeloid-derived suppressor cells when normal monocytes are exposed to glioma conditioned media. PMID:28666020

A forgotten facial nerve tumour: granular cell tumour of the parotid and its implications for treatment.

PubMed

Lerut, B; Vosbeck, J; Linder, T E

2011-04-01

We present a rare case of a facial nerve granular cell tumour in the right parotid gland, in a 10-year-old boy. A parotid or neurogenic tumour was suspected, based on magnetic resonance imaging. Intra-operatively, strong adhesions to surrounding structures were found, and a midfacial nerve branch had to be sacrificed for complete tumour removal. Recent reports verify that granular cell tumours arise from Schwann cells of peripheral nerve branches. The rarity of this tumour within the parotid gland, its origin from peripheral nerves, its sometimes misleading imaging characteristics, and its rare presentation with facial weakness and pain all have considerable implications on the surgical strategy and pre-operative counselling. Fine needle aspiration cytology may confirm the neurogenic origin of this lesion. When resecting the tumour, the surgeon must anticipate strong adherence to the facial nerve and be prepared to graft, or sacrifice, certain branches of this nerve.

Expression of podoplanin in Warthin tumours.

PubMed

Hansen, Torsten; Kirkpatrick, C James

2010-12-01

Warthin tumour is the second most common benign tumour of the parotid gland. This study was designed to investigate the lymphatic vessels in Warthin tumours in an effort to understand better its pathogenesis. Tissue specimens of 31 patients (19 men and 11 women; mean age 57 years, median size of the tumours 2.86 cm) were analysed by means of immunohistochemistry applying the monoclonal antibody D2-40. We found numerous D2-40-positive sinus-like vessels particularly at the inner layer of the capsule. Since subcapsular sinuses are a major morphological feature of lymph nodes in general, the finding of podoplanin expression in the large majority of subcapsular vessels in Warthin tumours confirms the view that this tumour has its origin in regional lymph nodes.

Deep tissue volume imaging of birefringence through fibre-optic needle probes for the delineation of breast tumour

NASA Astrophysics Data System (ADS)

Villiger, Martin; Lorenser, Dirk; McLaughlin, Robert A.; Quirk, Bryden C.; Kirk, Rodney W.; Bouma, Brett E.; Sampson, David D.

2016-07-01

Identifying tumour margins during breast-conserving surgeries is a persistent challenge. We have previously developed miniature needle probes that could enable intraoperative volume imaging with optical coherence tomography. In many situations, however, scattering contrast alone is insufficient to clearly identify and delineate malignant regions. Additional polarization-sensitive measurements provide the means to assess birefringence, which is elevated in oriented collagen fibres and may offer an intrinsic biomarker to differentiate tumour from benign tissue. Here, we performed polarization-sensitive optical coherence tomography through miniature imaging needles and developed an algorithm to efficiently reconstruct images of the depth-resolved tissue birefringence free of artefacts. First ex vivo imaging of breast tumour samples revealed excellent contrast between lowly birefringent malignant regions, and stromal tissue, which is rich in oriented collagen and exhibits higher birefringence, as confirmed with co-located histology. The ability to clearly differentiate between tumour and uninvolved stroma based on intrinsic contrast could prove decisive for the intraoperative assessment of tumour margins.

Residential Radon and Brain Tumour Incidence in a Danish Cohort

PubMed Central

Bräuner, Elvira V.; Andersen, Zorana J.; Andersen, Claus E.; Pedersen, Camilla; Gravesen, Peter; Ulbak, Kaare; Hertel, Ole; Loft, Steffen; Raaschou-Nielsen, Ole

2013-01-01

Background Increased brain tumour incidence over recent decades may reflect improved diagnostic methods and clinical practice, but remain unexplained. Although estimated doses are low a relationship between radon and brain tumours may exist. Objective To investigate the long-term effect of exposure to residential radon on the risk of primary brain tumour in a prospective Danish cohort. Methods During 1993–1997 we recruited 57,053 persons. We followed each cohort member for cancer occurrence from enrolment until 31 December 2009, identifying 121 primary brain tumour cases. We traced residential addresses from 1 January 1971 until 31 December 2009 and calculated radon concentrations at each address using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate-ratios (IRR) and 95% confidence intervals (CI) for the risk of primary brain tumours associated with residential radon exposure with adjustment for age, sex, occupation, fruit and vegetable consumption and traffic-related air pollution. Effect modification by air pollution was assessed. Results Median estimated radon was 40.5 Bq/m3. The adjusted IRR for primary brain tumour associated with each 100 Bq/m3 increment in average residential radon levels was 1.96 (95% CI: 1.07; 3.58) and this was exposure-dependently higher over the four radon exposure quartiles. This association was not modified by air pollution. Conclusions We found significant associations and exposure-response patterns between long-term residential radon exposure radon in a general population and risk of primary brain tumours, adding new knowledge to this field. This finding could be chance and needs to be challenged in future studies. PMID:24066143

MITOSTATIN, a putative tumor suppressor on chromosome 12q24.1, is downregulated in human bladder and breast cancer.

PubMed

Vecchione, A; Fassan, M; Anesti, V; Morrione, A; Goldoni, S; Baldassarre, G; Byrne, D; D'Arca, D; Palazzo, J P; Lloyd, J; Scorrano, L; Gomella, L G; Iozzo, R V; Baffa, R

2009-01-15

Allelic deletions on human chromosome 12q24 are frequently reported in a variety of malignant neoplasms, indicating the presence of a tumor suppressor gene(s) in this chromosomal region. However, no reasonable candidate has been identified so far. In this study, we report the cloning and functional characterization of a novel mitochondrial protein with tumor suppressor activity, henceforth designated MITOSTATIN. Human MITOSTATIN was found within a 3.2-kb transcript, which encoded a approximately 62 kDa, ubiquitously expressed protein with little homology to any known protein. We found homozygous deletions and mutations of MITOSTATIN gene in approximately 5 and approximately 11% of various cancer-derived cells and solid tumors, respectively. When transiently overexpressed, MITOSTATIN inhibited colony formation, tumor cell growth and was proapoptotic, all features shared by established tumor suppressor genes. We discovered a specific link between MITOSTATIN overexpression and downregulation of Hsp27. Conversely, MITOSTATIN knockdown cells showed an increase in cell growth and cell survival rates. Finally, MITOSTATIN expression was significantly reduced in primary bladder and breast tumors, and its reduction was associated with advanced tumor stages. Our findings support the hypothesis that MITOSTATIN has many hallmarks of a classical tumor suppressor in solid tumors and may play an important role in cancer development and progression.

The human ARF tumor suppressor senses blastema activity and suppresses epimorphic tissue regeneration

PubMed Central

Hesse, Robert G; Kouklis, Gayle K; Ahituv, Nadav; Pomerantz, Jason H

2015-01-01

The control of proliferation and differentiation by tumor suppressor genes suggests that evolution of divergent tumor suppressor repertoires could influence species’ regenerative capacity. To directly test that premise, we humanized the zebrafish p53 pathway by introducing regulatory and coding sequences of the human tumor suppressor ARF into the zebrafish genome. ARF was dormant during development, in uninjured adult fins, and during wound healing, but was highly expressed in the blastema during epimorphic fin regeneration after amputation. Regenerative, but not developmental signals resulted in binding of zebrafish E2f to the human ARF promoter and activated conserved ARF-dependent Tp53 functions. The context-dependent activation of ARF did not affect growth and development but inhibited regeneration, an unexpected distinct tumor suppressor response to regenerative versus developmental environments. The antagonistic pleiotropic characteristics of ARF as both tumor and regeneration suppressor imply that inducing epimorphic regeneration clinically would require modulation of ARF –p53 axis activation. DOI: http://dx.doi.org/10.7554/eLife.07702.001 PMID:26575287

Spinal intradural primary germ cell tumour--review of literature and case report.

PubMed

Biswas, Ahitagni; Puri, Tarun; Goyal, Shikha; Gupta, Ruchika; Eesa, Muneer; Julka, Pramod Kumar; Rath, Goura Kishor

2009-03-01

Primary spinal cord germ cell tumour is a rare tumour. We herein review the tumour characteristics, associated risk factors, treatment policy, and patterns of failure of primary intradural germ cell tumour. We conducted a PUBMED search using a combination of keywords such as "spinal germ cell tumor," "germinoma," "extradural," "intradural," "intramedullary," "extramedullary," and identified 19 cases of primary spinal germ cell tumour. Clinical features, pathologic characteristics, and treatment details of these patients including status at follow-up were noted from respective case reports. We also describe a case of a young Indian patient of intradural extramedullary germ cell tumour treated with a combination of surgery, chemotherapy, and radiotherapy. The median age at presentation was 24 years. The most common location of the tumour was thoracic (40%). Beta-HCG overproduction was noted in 40% of the patients. Most patients were treated with a combination of surgery, radiation therapy, and systemic chemotherapy. Median follow-up was 16.5 months. Recurrence was observed in 10% of the patients, all in beta-HCG over-producing tumours. The illustrative case was a 28-year male, presenting with pain in lower back and both lower limbs for 2 months. Magnetic resonance imaging spine showed an inhomogeneous hyperintense soft tissue mass at L(2)-L(4) spinal level. He was treated with complete surgical excision and four cycles of chemotherapy with BEP regimen following a histological diagnosis of non-seminomatous germ cell tumour. Palliative irradiation to the lumbar spine was given on progression at 3 months. The patient eventually succumbed to his condition, due to compressive transverse myelitis possibly due to cervical cord metastasis. Limited surgery followed by upfront radiation therapy and adjuvant chemotherapy is the optimal management of this rare group of tumour. Omission of radiation therapy from the treatment armamentarium might engender local recurrence and

Canine transmissible venereal tumour: a morphological and immunohistochemical study of 11 tumours in growth phase and during regression after chemotherapy.

PubMed

Gonzalez, C M; Griffey, S M; Naydan, D K; Flores, E; Cepeda, R; Cattaneo, G; Madewell, B R

2000-05-01

Eleven dogs with canine transmissible venereal tumour (CTVT) were given vincristine sulphate chemotherapy to induce tumour regression. Biopsy specimens were collected from tumours during the growth phase, before chemotherapy, and again from the same dogs during the regression induced by chemotherapy. Laboratory assessment included cytology, histology, the number of tumour cells in relation to the number of intratumoral leucocytes, proliferative and apoptotic fractions of tumour cells, intratumoral vessel density, and fibrosis. The results revealed that during regression, tumour cell proliferation ceased, apoptosis increased, leucocytes increased (with increased proportion of T lymphocytes), tumour parenchyma collapsed around intratumoral vessels, and fibrosis increased. These results, which were similar to findings in dogs with spontaneous regression of CTVT, suggest that tumour immunity plays a role in tumour regression after modest chemotherapy. Copyright 2000 Harcourt Publishers Ltd.

Regulators of pseudohyphal differentiation in Saccharomyces cerevisiae identified through multicopy suppressor analysis in ammonium permease mutant strains.

PubMed Central

Lorenz, M C; Heitman, J

1998-01-01

Nitrogen-starved diploid cells of the yeast Saccharomyces cerevisiae differentiate into a filamentous, pseudohyphal growth form. Recognition of nitrogen starvation is mediated, at least in part, by the ammonium permease Mep2p and the Galpha subunit Gpa2p. Genetic activation of the pheromone-responsive MAP kinase cascade, which is also required for filamentous growth, only weakly suppresses the filamentation defect of Deltamep2/Deltamep2 and Deltagpa2/Deltagpa2 strain. Surprisingly, deletion of Mep1p, an ammonium permease not previously thought to regulate differentiation, significantly enhances the potency of MAP kinase activation, such that the STE11-4 allele induces filamentation to near wild-type levels in Deltamep1/Deltamep1 Deltamep2/Deltamep2 and Deltamep1/Deltamep1 Deltagpa2/Deltagpa2 strains. To identify additional regulatory components, we isolated high-copy suppressors of the filamentation defect of the Deltamep1/Deltamep1 Deltamep2/Deltamep2 mutant. Multicopy expression of TEC1, PHD1, PHD2 (MSS10/MSN1/FUP4), MSN5, CDC6, MSS11, MGA1, SKN7, DOT6, HMS1, HMS2, or MEP2 each restored filamentation in a Deltamep1/Deltamep1 Deltamep2/Deltamep2 strain. Overexpression of SRK1 (SSD1), URE2, DAL80, MEP1, or MEP3 suppressed only the growth defect of the Deltamep1/Deltamep1 Deltamep2/Deltamep2 mutant strain. Characterization of these genes through deletion analysis and epistasis underscores the complexity of this developmental pathway and suggests that stress conditions other than nitrogen deprivation may also promote filamentous growth. PMID:9832522

RNA-Seq Differentiates Tumour and Host mRNA Expression Changes Induced by Treatment of Human Tumour Xenografts with the VEGFR Tyrosine Kinase Inhibitor Cediranib

PubMed Central

Bradford, James R.; Farren, Matthew; Powell, Steve J.; Runswick, Sarah; Weston, Susie L.; Brown, Helen; Delpuech, Oona; Wappett, Mark; Smith, Neil R.; Carr, T. Hedley; Dry, Jonathan R.; Gibson, Neil J.; Barry, Simon T.

2013-01-01

Pre-clinical models of tumour biology often rely on propagating human tumour cells in a mouse. In order to gain insight into the alignment of these models to human disease segments or investigate the effects of different therapeutics, approaches such as PCR or array based expression profiling are often employed despite suffering from biased transcript coverage, and a requirement for specialist experimental protocols to separate tumour and host signals. Here, we describe a computational strategy to profile transcript expression in both the tumour and host compartments of pre-clinical xenograft models from the same RNA sample using RNA-Seq. Key to this strategy is a species-specific mapping approach that removes the need for manipulation of the RNA population, customised sequencing protocols, or prior knowledge of the species component ratio. The method demonstrates comparable performance to species-specific RT-qPCR and a standard microarray platform, and allowed us to quantify gene expression changes in both the tumour and host tissue following treatment with cediranib, a potent vascular endothelial growth factor receptor tyrosine kinase inhibitor, including the reduction of multiple murine transcripts associated with endothelium or vessels, and an increase in genes associated with the inflammatory response in response to cediranib. In the human compartment, we observed a robust induction of hypoxia genes and a reduction in cell cycle associated transcripts. In conclusion, the study establishes that RNA-Seq can be applied to pre-clinical models to gain deeper understanding of model characteristics and compound mechanism of action, and to identify both tumour and host biomarkers. PMID:23840389

MicroRNA-211-5p suppresses tumour cell proliferation, invasion, migration and metastasis in triple-negative breast cancer by directly targeting SETBP1.

PubMed

Chen, Liang-Liang; Zhang, Zhou-Jing; Yi, Zhan-Bo; Li, Jian-Jun

2017-06-27

Triple-negative breast cancer (TNBC) accounts for 15-20% of all breast cancer in women globally. This subtype often has early and high recurrence rates, resulting in poor survival, partially due to lack of targeted therapies. To date, the detailed molecular mechanisms underlying TNBC progression are unclear. Given the crucial role of microRNAs (miRNAs) in cancer metastasis, we aimed to analyse the expression and function of a metastasis-associated miRNA named miR-211-5p in TNBC. MiRNA array analysis was performed to search for metastasis-associated miRNAs in TNBC. The miR-211-5p expression in tumour tissues, adjacent non-tumourous breast tissues of TNBC patients and cell lines were evaluated by real-time PCR. The protein expression levels were analysed by western blot, immunohistochemistry and in situ hybridisation. Luciferase reporter assays were employed to validate the target of miR-211-5p. The effect of miR-211-5p on TNBC progression was investigated in vitro and in vivo. MiR-211-5p was significantly downregulated in TNBC, and its expression level was associated with overall survival in TNBC. The expression of miR-211-5p suppressed TNBC cell proliferation, invasion, migration and metastasis in vitro and in vivo. Furthermore, SETBP1 was identified as a target of miR-211-5p. Through gain-of-function and loss-of-function studies, SETBP1 was shown to significantly affect colony and cell number in vitro. Enforced expression of miR-211-5p inhibited the expression of SETBP1 significantly and the restoration of SETBP1 expression reversed the inhibitory effects of miR-211-5p on TNBC cell proliferation and metastasis. These findings collectively demonstrate a tumour suppressor role of miR-211-5p in TNBC progression by targeting SETBP1, suggesting that miR-211-5p could serve as a potential prognostic biomarker and therapeutic target for TNBC.

Size Matters: Developing Design Rules to Engineer Nanoparticles for Solid Tumour Targeting

NASA Astrophysics Data System (ADS)

Sykes, Edward Alexander

Nanotechnology enables the design of highly customizable platforms for producing minimally invasive and programmable strategies for cancer diagnosis and treatment. Advances in this field have demonstrated that nanoparticles can enhance specificity of anti-cancer agents, respond to tumour-specific cues, and direct the visualization of biological targets in vivo. . Nanoparticles can be synthesized within the 1 to 100 nm range to achieve different electromagnetic properties and specifically interact with biological tissues by tuning their size, shape, and surface chemistry. However, it remains unclear which physicochemical parameters are critical for delivering nanomaterials to the tumour site. With less than 5% of administered nanoparticles reaching the tumour, engineering of nanoparticles for effective delivery to solid tumours remains a critical challenge to cancer nanomedicine. A more comprehensive understanding of the interplay between the nanomaterial physicochemical properties and biological systems is necessary to enhance the efficacy of nanoparticle tumour targeting. This thesis explores how nanoparticle size and functionalization with cancer cell specific agents impact nanoparticle delivery to tumours. Furthermore, this doctoral work (i) discusses how tumour structure evolves with growth, (ii) elucidates how such changes modulate nanoparticle accumulation, and (iii) identifies how the skin serves as a significant off-target site for nanoparticle uptake. This thesis also demonstrates the utility of empirically-derived parametric models, Monte Carlo simulations, and decision matrices for mechanistically understanding and predicting the impact of nanomaterial features and tumour biology on nanoparticle fate in vivo. These topics establish key design considerations to tailor nanoparticles for enhanced tumour targeting. Collectively, the concepts presented herein form a fundamental framework for the development of personalized nanomedicine and nano

Investigating intracranial tumour growth patterns with multiparametric MRI incorporating Gd‐DTPA and USPIO‐enhanced imaging

PubMed Central

Borri, Marco; Jury, Alexa; Popov, Sergey; Box, Gary; Perryman, Lara; Eccles, Suzanne A.; Jones, Chris; Robinson, Simon P.

2016-01-01

Abstract High grade and metastatic brain tumours exhibit considerable spatial variations in proliferation, angiogenesis, invasion, necrosis and oedema. Vascular heterogeneity arising from vascular co‐option in regions of invasive growth (in which the blood–brain barrier remains intact) and neoangiogenesis is a major challenge faced in the assessment of brain tumours by conventional MRI. A multiparametric MRI approach, incorporating native measurements and both Gd‐DTPA (Magnevist) and ultrasmall superparamagnetic iron oxide (P904)‐enhanced imaging, was used in combination with histogram and unsupervised cluster analysis using a k‐means algorithm to examine the spatial distribution of vascular parameters, water diffusion characteristics and invasion in intracranially propagated rat RG2 gliomas and human MDA‐MB‐231 LM2–4 breast adenocarcinomas in mice. Both tumour models presented with higher ΔR 1 (the change in transverse relaxation rate R 1 induced by Gd‐DTPA), fractional blood volume (fBV) and apparent diffusion coefficient than uninvolved regions of the brain. MDA‐MB‐231 LM2–4 tumours were less densely cellular than RG2 tumours and exhibited substantial local invasion, associated with oedema, whereas invasion in RG2 tumours was minimal. These additional features were reflected in the more heterogeneous appearance of MDA‐MB‐231 LM2–4 tumours on T 2‐weighted images and maps of functional MRI parameters. Unsupervised cluster analysis separated subregions with distinct functional properties; areas with a low fBV and relatively impermeable blood vessels (low ΔR 1) were predominantly located at the tumour margins, regions of MDA‐MB‐231 LM2–4 tumours with relatively high levels of water diffusion and low vascular permeability and/or fBV corresponded to histologically identified regions of invasion and oedema, and areas of mismatch between vascular permeability and blood volume were identified. We demonstrate that dual contrast MRI

[Contact shot from infantry weapons with a flash-suppressor].

PubMed

Perdekamp, Markus Grosse; Braunwarth, Roland; Schmidt, Ulrike; Schmidt, Wolfgang; Pollak, Stefan

2003-01-01

The number of reports on contact shots from firearms with a flash suppressor attached to the muzzle is small. On the basis of a case report (suicidal shot to the forehead with a Kalschnikow AKMS 47 assault rifle) the morphological peculiarities (characteristics soot pattern, relatively small powder cavity and only minor skin tears in the presence of a bony support) are presented and the conclusions to be drawn from the findings regarding the flash-suppressor, the shot distance, the angle of the shot and the way of holding the weapon are discussed.

Update on testis tumours.

PubMed

Berney, Daniel M

2012-08-01

The range of testicular tumours is so large that many pathologists may encounter the rarer variants only a few times, if at all, in their career. This rarity and complexity results in immense challenges for pathologists. For clinicians, due to their rarity and the high cure rate, the difficulty in conducting randomised trials in this area, even in the more common germ cell tumours, means that progress is slow and it is difficult to accumulate evidence for the relevance of the various histopathological risk factors for recurrence. A number of recent trials and retrospective analyses have suggested that some histopathological features suggestive of recurrence are more important than others. This has implications both in how testicular tumours are examined macroscopically and microscopically. New clinically important entities will also be described, as well as some pitfalls in the diagnosis of testicular tumours and how to avoid them.

A mathematical model of tumour and blood pHe regulation: The HCO3-/CO2 buffering system.

PubMed

Martin, Natasha K; Gaffney, Eamonn A; Gatenby, Robert A; Gillies, Robert J; Robey, Ian F; Maini, Philip K

2011-03-01

Malignant tumours are characterised by a low, acidic extracellular pH (pHe) which facilitates invasion and metastasis. Previous research has proposed the potential benefits of manipulating systemic pHe, and recent experiments have highlighted the potential for buffer therapy to raise tumour pHe, prevent metastases, and prolong survival in laboratory mice. To examine the physiological regulation of tumour buffering and investigate how perturbations of the buffering system (via metabolic/respiratory disorders or changes in parameters) can alter tumour and blood pHe, we develop a simple compartmentalised ordinary differential equation model of pHe regulation by the HCO3-/CO2 buffering system. An approximate analytical solution is constructed and used to carry out a sensitivity analysis, where we identify key parameters that regulate tumour pHe in both humans and mice. From this analysis, we suggest promising alternative and combination therapies, and identify specific patient groups which may show an enhanced response to buffer therapy. In addition, numerical simulations are performed, validating the model against well-known metabolic/respiratory disorders and predicting how these disorders could change tumour pHe. Copyright © 2010 Elsevier Inc. All rights reserved.

LARG at chromosome 11q23 has functional characteristics of a tumor suppressor in human breast cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ong, Danny C.T.; Rudduck, Christina; Chin, Koei

2008-05-06

Deletion of 11q23-q24 is frequent in a diverse variety of malignancies, including breast and colorectal carcinoma, implicating the presence of a tumor suppressor gene at that chromosomal region. We show here that LARG, from 11q23, has functional characteristics of a tumor suppressor. We examined a 6-Mb region on 11q23 by high-resolution deletion mapping, utilizing both loss of heterozygosity (LOH) analysis and microarray comparative genomic hybridization (CGH). LARG (also called ARHGEF12), identified from the analyzed region, was underexpressed in 34% of primary breast carcinomas and 80% of breast cancer cell lines including the MCF-7 line. Multiplex ligation-dependent probe amplification on 30more » primary breast cancers and six breast cancer cell lines showed that LARG had the highest frequency of deletion compared to the BCSC-1 and TSLC1 genes, two known candidate tumor suppressor genes from 11q. In vitro analysis of breast cancer cell lines that underexpress LARG showed that LARG could be reactivated by trichostatin A, a histone deacetylase inhibitor, but not by 5-Aza-2{prime}-deoxycytidine, a demethylating agent. Bisulfite sequencing and quantitative high-throughput analysis of DNA methylation confirmed the lack of CpG island methylation in LARG in breast cancer. Restoration of LARG expression in MCF-7 cells by stable transfection resulted in reduced proliferation and colony formation, suggesting that LARG has functional characteristics of a tumor suppressor gene.« less

Small RNA binding is a common strategy to suppress RNA silencing by several viral suppressors

PubMed Central

Lakatos, Lóránt; Csorba, Tibor; Pantaleo, Vitantonio; Chapman, Elisabeth J; Carrington, James C; Liu, Yu-Ping; Dolja, Valerian V; Calvino, Lourdes Fernández; López-Moya, Juan José; Burgyán, József

2006-01-01

RNA silencing is an evolutionarily conserved system that functions as an antiviral mechanism in higher plants and insects. To counteract RNA silencing, viruses express silencing suppressors that interfere with both siRNA- and microRNA-guided silencing pathways. We used comparative in vitro and in vivo approaches to analyse the molecular mechanism of suppression by three well-studied silencing suppressors. We found that silencing suppressors p19, p21 and HC-Pro each inhibit the intermediate step of RNA silencing via binding to siRNAs, although the molecular features required for duplex siRNA binding differ among the three proteins. None of the suppressors affected the activity of preassembled RISC complexes. In contrast, each suppressor uniformly inhibited the siRNA-initiated RISC assembly pathway by preventing RNA silencing initiator complex formation. PMID:16724105

[Bellini tumours].

PubMed

Teghom, Corine; Gachet, Julie; Scotté, Florian; Elaidi, Reza; Oudard, Stéphane

2011-10-01

In Europe, renal tumours are 7th in frequency of men cancers. They are rare tumours in 10 to 15% of cases. Collecting ducts carcinomas or Bellini tumours, described for the first time in 1949, are a distinct clinical and pathological entity. They represented 1% of epithelial cancers. Nephrectomy is the treatment of localised cancer. Because of lack of recommendations, usually in clinical practice, treatment is similar to urothelial carcinomas treatments (gemcitabine plus platinium). A 72% of response rate of urothelial carcinoma to association of bevacizumab with platinium and gemcitabine 1st line chemotherapy in metastatic setting was reported. More, cases of responses of metastatic Bellini cancers to antiangiogenic treatments associated to chemotherapy were reported these last years. Bellini cancers have a poor prognostic. Unless the fact that this cancer is aggressive, after nephrectomy, cancer specific survival seems not to be different to those of patients with clear cells renal carcinoma and could be related to latest stage of disease in patients. The evaluation of efficacy of association of bevacizumab to chemotherapy is still going on in this association.

Tetramer formation of tumor suppressor protein p53: Structure, function, and applications.

PubMed

Kamada, Rui; Toguchi, Yu; Nomura, Takao; Imagawa, Toshiaki; Sakaguchi, Kazuyasu

2016-11-04

Tetramer formation of p53 is essential for its tumor suppressor function. p53 not only acts as a tumor suppressor protein by inducing cell cycle arrest and apoptosis in response to genotoxic stress, but it also regulates other cellular processes, including autophagy, stem cell self-renewal, and reprogramming of differentiated cells into stem cells, immune system, and metastasis. More than 50% of human tumors have TP53 gene mutations, and most of them are missense mutations that presumably reduce tumor suppressor activity of p53. This review focuses on the role of the tetramerization (oligomerization), which is modulated by the protein concentration of p53, posttranslational modifications, and/or interactions with its binding proteins, in regulating the tumor suppressor function of p53. Functional control of p53 by stabilizing or inhibiting oligomer formation and its bio-applications are also discussed. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 598-612, 2016. © 2015 Wiley Periodicals, Inc.

Targeting LKB1 in cancer – exposing and exploiting vulnerabilities

PubMed Central

Momcilovic, M; Shackelford, D B

2015-01-01

The LKB1 tumour suppressor is a serine/threonine kinase that functions as master regulator of cell growth, metabolism, survival and polarity. LKB1 is frequently mutated in human cancers and research spanning the last two decades have begun decoding the cellular pathways deregulated following LKB1 inactivation. This work has led to the identification of vulnerabilities present in LKB1-deficient tumour cells. Pre-clinical studies have now identified therapeutic strategies targeting this subset of tumours that promise to benefit this large patient population harbouring LKB1 mutations. Here, we review the current efforts that are underway to translate pre-clinical discovery of therapeutic strategies targeting LKB1 mutant cancers into clinical practice. PMID:26196184

Enhanced Transgene Expression in Sugarcane by Co-Expression of Virus-Encoded RNA Silencing Suppressors

PubMed Central

Park, Jong-Won; Beyene, Getu; Buenrostro-Nava, Marco T.; Molina, Joe; Wang, Xiaofeng; Ciomperlik, Jessica J.; Manabayeva, Shuga A.; Alvarado, Veria Y.; Rathore, Keerti S.; Scholthof, Herman B.; Mirkov, T. Erik

2013-01-01

Post-transcriptional gene silencing is commonly observed in polyploid species and often poses a major limitation to plant improvement via biotechnology. Five plant viral suppressors of RNA silencing were evaluated for their ability to counteract gene silencing and enhance the expression of the Enhanced Yellow Fluorescent Protein (EYFP) or the β-glucuronidase (GUS) reporter gene in sugarcane, a major sugar and biomass producing polyploid. Functionality of these suppressors was first verified in Nicotiana benthamiana and onion epidermal cells, and later tested by transient expression in sugarcane young leaf segments and protoplasts. In young leaf segments co-expressing a suppressor, EYFP reached its maximum expression at 48–96 h post-DNA introduction and maintained its peak expression for a longer time compared with that in the absence of a suppressor. Among the five suppressors, Tomato bushy stunt virus-encoded P19 and Barley stripe mosaic virus-encoded γb were the most efficient. Co-expression with P19 and γb enhanced EYFP expression 4.6-fold and 3.6-fold in young leaf segments, and GUS activity 2.3-fold and 2.4-fold in protoplasts compared with those in the absence of a suppressor, respectively. In transgenic sugarcane, co-expression of GUS and P19 suppressor showed the highest accumulation of GUS levels with an average of 2.7-fold more than when GUS was expressed alone, with no detrimental phenotypic effects. The two established transient expression assays, based on young leaf segments and protoplasts, and confirmed by stable transgene expression, offer a rapid versatile system to verify the efficiency of RNA silencing suppressors that proved to be valuable in enhancing and stabilizing transgene expression in sugarcane. PMID:23799071

Overcoming resistance to molecularly targeted anticancer therapies: Rational drug combinations based on EGFR and MAPK inhibition for solid tumours and haematologic malignancies.

PubMed

Tortora, Giampaolo; Bianco, Roberto; Daniele, Gennaro; Ciardiello, Fortunato; McCubrey, James A; Ricciardi, Maria Rosaria; Ciuffreda, Ludovica; Cognetti, Francesco; Tafuri, Agostino; Milella, Michele

2007-06-01

Accumulating evidence suggests that cancer can be envisioned as a "signaling disease", in which alterations in the cellular genome affect the expression and/or function of oncogenes and tumour suppressor genes. This ultimately disrupts the physiologic transmission of biochemical signals that normally regulate cell growth, differentiation and programmed cell death (apoptosis). From a clinical standpoint, signal transduction inhibition as a therapeutic strategy for human malignancies has recently achieved remarkable success. However, as additional drugs move forward into the clinical arena, intrinsic and acquired resistance to "targeted" agents becomes an issue for their clinical utility. One way to overcome resistance to targeted agents is to identify genetic and epigenetic aberrations underlying sensitivity/resistance, thus enabling the selection of patients that will most likely benefit from a specific therapy. Since resistance often ensues as a result of the concomitant activation of multiple, often overlapping, signaling pathways, another possibility is to interfere with multiple, cross-talking pathways involved in growth and survival control in a rational, mechanism-based, fashion. These concepts may be usefully applied, among others, to agents that target two major signal transduction pathways: the one initiated by epidermal growth factor receptor (EGFR) signaling and the one converging on mitogen-activated protein kinase (MAPK) activation. Here, we review the molecular mechanisms of sensitivity/resistance to EGFR inhibitors, as well as the rationale for combining them with other targeted agents, in an attempt to overcome resistance. In the second part of the paper, we review MAPK-targeted agents, focusing on their therapeutic potential in haematologic malignancies, and examine the prospects for combinations of MAPK inhibitors with cytotoxic agents or other signal transduction-targeted agents to obtain synergistic anti-tumour effects.

Metabolite profiling in retinoblastoma identifies novel clinicopathological subgroups

PubMed Central

Kohe, Sarah; Brundler, Marie-Anne; Jenkinson, Helen; Parulekar, Manoj; Wilson, Martin; Peet, Andrew C; McConville, Carmel M

2015-01-01

Background: Tumour classification, based on histopathology or molecular pathology, is of value to predict tumour behaviour and to select appropriate treatment. In retinoblastoma, pathology information is not available at diagnosis and only exists for enucleated tumours. Alternative methods of tumour classification, using noninvasive techniques such as magnetic resonance spectroscopy, are urgently required to guide treatment decisions at the time of diagnosis. Methods: High-resolution magic-angle spinning magnetic resonance spectroscopy (HR-MAS MRS) was undertaken on enucleated retinoblastomas. Principal component analysis and cluster analysis of the HR-MAS MRS data was used to identify tumour subgroups. Individual metabolite concentrations were determined and were correlated with histopathological risk factors for each group. Results: Multivariate analysis identified three metabolic subgroups of retinoblastoma, with the most discriminatory metabolites being taurine, hypotaurine, total-choline and creatine. Metabolite concentrations correlated with specific histopathological features: taurine was correlated with differentiation, total-choline and phosphocholine with retrolaminar optic nerve invasion, and total lipids with necrosis. Conclusions: We have demonstrated that a metabolite-based classification of retinoblastoma can be obtained using ex vivo magnetic resonance spectroscopy, and that the subgroups identified correlate with histopathological features. This result justifies future studies to validate the clinical relevance of these subgroups and highlights the potential of in vivo MRS as a noninvasive diagnostic tool for retinoblastoma patient stratification. PMID:26348444

Differential Patterns of Vasculature to Liver Tumours

PubMed Central

Assa, J.

1970-01-01

An angiographic study of the vasculature of Vx2 tumour deposits in the rabbit's liver is described. Tumours transplanted from donor rabbits within less than 2 weeks incubation, developed into an amorphic infiltrating tumour, characterized by a rich arterial network. Tumours harvested after 3 weeks growth in donors, became cystic and had a scanty arterial supply. In both groups there was no portal circulation to the tumours' deposits. It is suggested that prior to intra-arterial treatment of cancer in the liver, the morphology of the tumour should be assessed. ImagesFigs. 3-4Figs. 5-6Figs. 7-8Figs. 1-2 PMID:5451574

Pitfalls in colour photography of choroidal tumours

PubMed Central

Schalenbourg, A; Zografos, L

2013-01-01

Colour imaging of fundus tumours has been transformed by the development of digital and confocal scanning laser photography. These advances provide numerous benefits, such as panoramic images, increased contrast, non-contact wide-angle imaging, non-mydriatic photography, and simultaneous angiography. False tumour colour representation can, however, cause serious diagnostic errors. Large choroidal tumours can be totally invisible on angiography. Pseudogrowth can occur because of artefacts caused by different methods of fundus illumination, movement of reference blood vessels, and flattening of Bruch's membrane and sclera when tumour regression occurs. Awareness of these pitfalls should prevent the clinician from misdiagnosing tumours and wrongfully concluding that a tumour has grown. PMID:23238442

Pitfalls in colour photography of choroidal tumours.

PubMed

Schalenbourg, A; Zografos, L

2013-02-01

Colour imaging of fundus tumours has been transformed by the development of digital and confocal scanning laser photography. These advances provide numerous benefits, such as panoramic images, increased contrast, non-contact wide-angle imaging, non-mydriatic photography, and simultaneous angiography. False tumour colour representation can, however, cause serious diagnostic errors. Large choroidal tumours can be totally invisible on angiography. Pseudogrowth can occur because of artefacts caused by different methods of fundus illumination, movement of reference blood vessels, and flattening of Bruch's membrane and sclera when tumour regression occurs. Awareness of these pitfalls should prevent the clinician from misdiagnosing tumours and wrongfully concluding that a tumour has grown.

Circulating tumour DNA and CT monitoring in patients with untreated diffuse large B-cell lymphoma: a correlative biomarker study.

PubMed

Roschewski, Mark; Dunleavy, Kieron; Pittaluga, Stefania; Moorhead, Martin; Pepin, Francois; Kong, Katherine; Shovlin, Margaret; Jaffe, Elaine S; Staudt, Louis M; Lai, Catherine; Steinberg, Seth M; Chen, Clara C; Zheng, Jianbiao; Willis, Thomas D; Faham, Malek; Wilson, Wyndham H

2015-05-01

Diffuse large-B-cell lymphoma is curable, but when treatment fails, outcome is poor. Although imaging can help to identify patients at risk of treatment failure, they are often imprecise, and radiation exposure is a potential health risk. We aimed to assess whether circulating tumour DNA encoding the clonal immunoglobulin gene sequence could be detected in the serum of patients with diffuse large-B-cell lymphoma and used to predict clinical disease recurrence after frontline treatment. We used next-generation DNA sequencing to retrospectively analyse cell-free circulating tumour DNA in patients assigned to one of three treatment protocols between May 8, 1993, and June 6, 2013. Eligible patients had diffuse large-B-cell lymphoma, no evidence of indolent lymphoma, and were previously untreated. We obtained serial serum samples and concurrent CT scans at specified times during most treatment cycles and up to 5 years of follow-up. VDJ gene segments of the rearranged immunoglobulin receptor genes were amplified and sequenced from pretreatment specimens and serum circulating tumour DNA encoding the VDJ rearrangements was quantitated. Tumour clonotypes were identified in pretreatment specimens from 126 patients who were followed up for a median of 11 years (IQR 6·8-14·2). Interim monitoring of circulating tumour DNA at the end of two treatment cycles in 108 patients showed a 5-year time to progression of 41·7% (95% CI 22·2-60·1) in patients with detectable circulating tumour DNA and 80·2% (69·6-87·3) in those without detectable circulating tumour DNA (p<0·0001). Detectable interim circulating tumour DNA had a positive predictive value of 62·5% (95% CI 40·6-81·2) and a negative predictive value of 79·8% (69·6-87·8). Surveillance monitoring of circulating tumour DNA was done in 107 patients who achieved complete remission. A Cox proportional hazards model showed that the hazard ratio for clinical disease progression was 228 (95% CI 51-1022) for patients who

Multicystic dedifferentiated retroperitoneal liposarcoma: tumour cyst fluid analysis and implications for management

PubMed Central

Khoury, Mitri; Sim, Geok Choo; Harao, Michiko; Radvanyi, Laszlo; Amini, Behrang; Benjamin, Robert S; Pisters, Peter W T; Pollock, Raphael E; Tseng, William W

2015-01-01

Liposarcomas are soft tissue sarcomas of adipocyte origin. We describe a case of a dedifferentiated retroperitoneal liposarcoma with an unusual presentation on recurrence as a large, multicystic tumour. The patient was a 72-year-old woman who had undergone multiple treatments including two prior resections. For her most recent locoregional disease recurrence, the patient was offered surgical debulking for symptom palliation. At this operation, performed after two cycles of chemotherapy, the tumour cyst fluid was analysed and found to have a predominance of immune cells with no identifiable malignant cells. This case and the results of our tumour cyst fluid analysis raise several interesting considerations for the management of this unique situation in a rare disease. PMID:26156843

A case of cetuximab-related tumour lysis syndrome in metastatic rectal carcinoma

PubMed Central

Haroon, Muhammad; Kwong, Whye Yan; Cantwell, Brian; Walker, Frank

2010-01-01

A 60-year-old man was diagnosed with a moderately differentiated adenocarcinoma in November 2006. The computed tomography (CT), magnetic resonance imaging (MRI) and whole-body positron emission tomography–CT (PET–CT) scan showed the presence of multiple liver metastases which were confined to its right lobe. He had the first session of a combined therapy with cetuximab and 5-fluorouracil (5-FU) in March 2009; however, soon afterwards, he presented with the symptoms, signs and biochemistry suggestive of tumour lysis syndrome. Our unusual case highlights that tumour lysis syndrome can also develop in ‘low risk’ category tumours, and that clinicians should be vigilant in identifying at-risk patients. PMID:28657052

Histopathology of malignant salivary gland tumours.

PubMed

Seifert, G

1992-07-01

This report is based upon the Salivary Gland Register in Hamburg and on the second revised edition of the WHO Histological Typing of Salivary Gland Tumours. The group of malignant salivary gland tumours contains carcinomas, malignant non-epithelial tumours, malignant lymphomas and secondary tumours. The various carcinomas are classified in a continuous separate listing because the different types are distinguished not only by histopathology, but also by differences in prognosis and treatment. The term "tumour" is replaced by "carcinoma" in two entities: acinic cell carcinoma and mucoepidermoid carcinoma. New entities are: polymorphous low-grade adenocarcinoma, basal cell adenocarcinoma, salivary duct carcinoma and malignant myoepithelioma. Carcinoma in pleomorphic adenoma can be distinguished as non-invasive and invasive carcinoma, and carcinosarcoma. Malignant non-epithelial tumours are mostly malignant fibrous histiocytoma, malignant schwannoma and rhabdomyosarcoma. The large majority of malignant lymphomas are non-Hodgkin-lymphomas with high differentiation. Many lymphomas are associated with chronic immunosialadenitis (Sjögren's syndrome). Secondary tumours are mostly metastases from primary squamous cell carcinomas or from melanomas of the skin (head and neck area). Haematogeneous metastases are very rare (mainly from lung, kidney or breast).

The Enamovirus P0 protein is a silencing suppressor which inhibits local and systemic RNA silencing through AGO1 degradation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fusaro, Adriana F.; CSIRO Plant Industry, Canberra, P.O. Box 1600, ACT 2601; Correa, Regis L.

The P0 protein of poleroviruses and P1 protein of sobemoviruses suppress the plant's RNA silencing machinery. Here we identified a silencing suppressor protein (SSP), P0{sup PE}, in the Enamovirus Pea enation mosaic virus-1 (PEMV-1) and showed that it and the P0s of poleroviruses Potato leaf roll virus and Cereal yellow dwarf virus have strong local and systemic SSP activity, while the P1 of Sobemovirus Southern bean mosaic virus supresses systemic silencing. The nuclear localized P0{sup PE} has no discernable sequence conservation with known SSPs, but proved to be a strong suppressor of local silencing and a moderate suppressor of systemicmore » silencing. Like the P0s from poleroviruses, P0{sup PE} destabilizes AGO1 and this action is mediated by an F-box-like domain. Therefore, despite the lack of any sequence similarity, the poleroviral and enamoviral SSPs have a conserved mode of action upon the RNA silencing machinery.« less

Integrated analysis identifies microRNA-195 as a suppressor of Hippo-YAP pathway in colorectal cancer.

PubMed

Sun, Min; Song, Haibin; Wang, Shuyi; Zhang, Chunxiao; Zheng, Liang; Chen, Fangfang; Shi, Dongdong; Chen, Yuanyuan; Yang, Chaogang; Xiang, Zhenxian; Liu, Qing; Wei, Chen; Xiong, Bin

2017-03-29

With persistent inconsistencies in colorectal cancer (CRC) miRNAs expression data, it is crucial to shift toward inclusion of a "pre-laboratory" integrated analysis to expedite effective precision medicine and translational research. Aberrant expression of hsa-miRNA-195 (miR-195) which is distinguished as a clinically noteworthy miRNA has previously been observed in multiple cancers, yet its role in CRC remains unclear. In this study, we performed an integrated analysis of seven CRC miRNAs expression datasets. The expression of miR-195 was validated in The Cancer Genome Atlas (TCGA) datasets, and an independent validation sample cohort. Colon cancer cells were transfected with miR-195 mimic and inhibitor, after which cell proliferation, colony formation, migration, invasion, and dual luciferase reporter were assayed. Xenograft mouse models were used to determine the role of miR-195 in CRC tumorigenicity in vivo. Four downregulated miRNAs (hsa-let-7a, hsa-miR-125b, hsa-miR-145, and hsa-miR-195) were demonstrated to be potentially useful diagnostic markers in the clinical setting. CRC patients with a decreased level of miR-195-5p in tumor tissues had significantly shortened survival as revealed by the TCGA colon adenocarcinoma (COAD) dataset and our CRC cohort. Overexpression of miR-195-5p in DLD1 and HCT116 cells repressed cell growth, colony formation, invasion, and migration. Inhibition of miR-195-5p function contributed to aberrant cell proliferation, migration, invasion, and epithelial mesenchymal transition (EMT). We identified miR-195-5p binding sites within the 3'-untranslated region (3'-UTR) of the human yes-associated protein (YAP) mRNA. YAP1 expression was downregulated after miR-195-5p treatment by qRT-PCR analysis and western blot. Four downregulated miRNAs were shown to be prime candidates for a panel of biomarkers with sufficient diagnostic accuracy for CRC in a clinical setting. Our integrated microRNA profiling approach identified miR-195-5p

Wilms tumour histology is determined by distinct types of precursor lesions and not epigenetic changes.

PubMed

Fukuzawa, R; Anaka, M R; Heathcott, R W; McNoe, L A; Morison, I M; Perlman, E J; Reeve, A E

2008-08-01

Current models of Wilms tumour development propose that histological features of the tumours are programmed by the underlying molecular aberrations. For example, tumours associated with WT1 mutations arise from intralobar nephrogenic rests (ILNR), concur with CTNNB1 mutations and have distinct histology, whereas tumours with IGF2 loss of imprinting (LOI) often arise from perilobar nephrogenic rests (PLNR). Intriguingly, ILNR and PLNR are found simultaneously in Wilms tumours in children with overgrowth who have constitutional IGF2 LOI. We therefore examined whether the precursor lesions or early epigenetic changes are the primary determinant of Wilms tumour histology. We examined the histological features and gene expression profiles of IGF2 LOI tumours and WT1-mutant tumours which are associated with PLNR and/or ILNR. Two distinct types of IGF2 LOI tumours were identified: the first type had a blastemal-predominant histology associated with PLNR, while the second subtype had a myogenic histology, increased expression of mesenchymal lineage genes and an association with ILNR, similar to WT1-mutant tumours. These ILNR-associated IGF2 LOI tumours also showed signatures of activation of the WNT signalling pathway: differential expression of beta-catenin targets (MMP2, RARG, DKK1) and WNT antagonist genes (DKK1, WIF1, SFRP4). Unexpectedly, the majority of these tumours had CTNNB1 mutations, which are normally only seen in WT1-mutant tumours. The absence of WT1 mutations in tumours with IGF2 LOI indicated that CTNNB1 mutations occur predominantly in tumours arising from ILNR independent of the presence or absence of WT1 mutations. Thus, even though these two classes of tumours with IGF2 LOI have the same underlying predisposing epigenetic error, the tumour histology and the gene expression profiles are determined by the nature of the precursor cells within the nephrogenic rests and subsequent CTNNB1 mutations. Copyright (c) 2008 Pathological Society of Great Britain and

Solitary fibrous tumour of the cheek: An unusual presentation of a rare soft tissue tumour

PubMed Central

Jones, JL; Jones, AV; Drage, NA; Bhatia, S; Hourihan, MD

2014-01-01

This case report discusses the unusual presentation and ultrasound features of a solitary fibrous tumour of the face. Solitary fibrous tumour is an uncommon form of soft tissue tumour which, although seen predominantly within the lung pleura, can occur throughout the body in sites such as the peritoneum, mediastinum and head and neck. Ultrasound is an excellent imaging modality in the assessment of soft tissue masses in the head and neck. The ultrasound features demonstrated by this example of solitary fibrous tumour are reviewed. This report also highlights that ultrasound alone is ultimately limited in reaching a definitive diagnosis. The roles of other investigations such as ultrasound-guided biopsy and cross-sectional imaging are discussed. PMID:27433225

Intronic splicing mutations in PTCH1 cause Gorlin syndrome.

PubMed

Bholah, Zaynab; Smith, Miriam J; Byers, Helen J; Miles, Emma K; Evans, D Gareth; Newman, William G

2014-09-01

Gorlin syndrome is an autosomal dominant disorder characterized by multiple early-onset basal cell carcinoma, odontogenic keratocysts and skeletal abnormalities. It is caused by heterozygous mutations in the tumour suppressor PTCH1. Routine clinical genetic testing, by Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA) to confirm a clinical diagnosis of Gorlin syndrome, identifies a mutation in 60-90 % of cases. We undertook RNA analysis on lymphocytes from ten individuals diagnosed with Gorlin syndrome, but without known PTCH1 mutations by exonic sequencing or MLPA. Two altered PTCH1 transcripts were identified. Genomic DNA sequence analysis identified an intron 7 mutation c.1068-10T>A, which created a strong cryptic splice acceptor site, leading to an intronic insertion of eight bases; this is predicted to create a frameshift p.(His358Alafs*12). Secondly, a deep intronic mutation c.2561-2057A>G caused an inframe insertion of 78 intronic bases in the cDNA transcript, leading to a premature stop codon p.(Gly854fs*3). The mutations are predicted to cause loss of function of PTCH1, consistent with its tumour suppressor function. The findings indicate the importance of RNA analysis to detect intronic mutations in PTCH1 not identified by routine screening techniques.

Effects of nandrolone decanoate on the toxicity and anti-tumour action of CCNU and FU in murine tumours.

PubMed Central

Bibby, M. C.; Double, J. A.; Mughal, M. A.

1981-01-01

Pre-treatment with the anabolic steroid nandrolone decanoate (ND) increases the LD50 of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) and 5-Fluorouracil (FU) in NMRI mice. Administration of ND did not affect the anti-tumour action of CCNU against a transplantable mouse adenocarcinoma of the colon (MAC 13) or the anti-tumour action of FU against MAC 26. In both tumour lines ND had no significant effect on tumour growth. These data suggest that an increase in the anti-tumour selectivity of these agents may be produced by pre-treatment with ND. PMID:7295514

Equine nasal and paranasal sinus tumours: part 2: a contribution of 28 case reports.

PubMed

Dixon, P M; Head, K W

1999-05-01

The clinical and pathological findings of 28 cases (27 horses, 1 donkey) of equid sinonasal tumours examined at the Edinburgh Veterinary School are presented and include: seven cases of squamous cell carcinoma (SCC); five adenocarcinomas; three undifferentiated carcinomas; two adenomas; five fibro-osseous and bone tumours; and single cases of ameloblastoma, fibroma, fibrosarcoma, undifferentiated sarcoma, melanoma and lymphosarcoma. The median ages of animals affected with epithelial, and fibro-osseous/bone tumours were 14 and 4 years, respectively. Unilateral purulent or mucopurulent nasal discharge (81% of cases) and gross facial swellings (82% of cases) were the most common presenting signs with sinonasal tumours, with epistaxis recorded in just 23% of cases. Radiology and endoscopy were the most useful ancillary diagnostic techniques. The maxillary area was the most common site of tumour origin, and only three cases were definitively identified as originating in the nasal cavity. Four of the maxillary SCC lesions originated within the nasal cavities or maxillary sinuses, while two originated in the oral cavity. Fourteen of 15 carcinomas, but only two of the 13 remaining tumours, spread to other sites in the head. Only three cases of sinonasal tumour had lymph node metastases, and none had distant metastases. In the long term, surgical treatment with seven malignant tumours was unsuccessful (6 months median survival post-operatively), but was successful with four out of five benign tumours (no regrowth at a median of 4 years post-operatively).

Naturally occurring tumours in the basal metazoan Hydra.

PubMed

Domazet-Lošo, Tomislav; Klimovich, Alexander; Anokhin, Boris; Anton-Erxleben, Friederike; Hamm, Mailin J; Lange, Christina; Bosch, Thomas C G

2014-06-24

The molecular nature of tumours is well studied in vertebrates, although their evolutionary origin remains unknown. In particular, there is no evidence for naturally occurring tumours in pre-bilaterian animals, such as sponges and cnidarians. This is somewhat surprising given that recent computational studies have predicted that most metazoans might be prone to develop tumours. Here we provide first evidence for naturally occurring tumours in two species of Hydra. Histological, cellular and molecular data reveal that these tumours are transplantable and might originate by differentiation arrest of female gametes. Growth of tumour cells is independent from the cellular environment. Tumour-bearing polyps have significantly reduced fitness. In addition, Hydra tumours show a greatly altered transcriptome that mimics expression shifts in vertebrate cancers. Therefore, this study shows that spontaneous tumours have deep evolutionary roots and that early branching animals may be informative in revealing the fundamental mechanisms of tumorigenesis.

CNS embryonal tumours: WHO 2016 and beyond.

PubMed

Pickles, J C; Hawkins, C; Pietsch, T; Jacques, T S

2018-02-01

Embryonal tumours of the central nervous system (CNS) present a significant clinical challenge. Many of these neoplasms affect young children, have a very high mortality and therapeutic strategies are often aggressive with poor long-term outcomes. There is a great need to accurately diagnose embryonal tumours, predict their outcome and adapt therapy to the individual patient's risk. For the first time in 2016, the WHO classification took into account molecular characteristics for the diagnosis of CNS tumours. This integration of histological features with genetic information has significantly changed the diagnostic work-up and reporting of tumours of the CNS. However, this remains challenging in embryonal tumours due to their previously unaccounted tumour heterogeneity. We describe the recent revisions made to the 4th edition of the WHO classification of CNS tumours and review the main changes, while highlighting some of the more common diagnostic testing strategies. © 2017 British Neuropathological Society.

Interstitial ultrasound ablation of vertebral and paraspinal tumours: Parametric and patient-specific simulations

PubMed Central

Scott, Serena J.; Salgaonkar, Vasant; Prakash, Punit; Burdette, E. Clif; Diederich, Chris J.

2015-01-01

Purpose Theoretical parametric and patient-specific models are applied to assess the feasibility of interstitial ultrasound ablation of tumours in and near the spine and to identify potential treatment delivery strategies. Methods 3D patient-specific finite element models (n=11) of interstitial ultrasound ablation of tumours associated with spine were generated. Gaseous nerve insulation and various applicator configurations, frequencies (3 and 7 MHz), placement trajectories, and tumour locations were simulated. Parametric studies with multilayered models investigated the impacts of tumour attenuation, tumour dimension, and the thickness of bone insulating critical structures. Temperature and thermal dose were calculated to define ablation (>240 equivalent minutes at 43°C (EM43°C)) and safety margins (<45°C & <6 EM43°C), and to determine performance and required delivery parameters. Results Osteolytic tumours (≤44 mm) encapsulated by bone could be successfully ablated with 7 MHz interstitial ultrasound (8.1-16.6 W/cm2, 120-5900 J, 0.4-15 min). Ablation of tumours (94.6-100% volumetric) 0-14.5 mm from the spinal canal was achieved within 3-15 min without damaging critical nerves. 3 MHz devices provided faster ablation (390 versus 930 s) of an 18 mm diameter osteoblastic (high bone content) volume than 7 MHz devices. Critical anatomy in proximity to the tumour could be protected by selection of appropriate applicator configurations, active sectors, and applied power schemas, and through gaseous insulation. Preferential ultrasound absorption at bone surfaces facilitated faster, more effective ablations in osteolytic tumours and provided isolation of ablative energies and temperatures. Conclusions Parametric and patient-specific studies demonstrated the feasibility and potential advantages of interstitial ultrasound ablation treatment of paraspinal and osteolytic vertebral tumours. PMID:25017322

Prevalence of exon 11 internal tandem duplications in the C-KIT proto-oncogene in Australian canine mast cell tumours.

PubMed

Tamlin, V S; Kessell, A E; Mccoy, R J; Dobson, E C; Smith, T S; Hebart, M; Brown, L; Mitrovic, D; Peaston, A E

2017-10-01

To measure the prevalence of internal tandem duplications (ITDs) in exon 11 of the proto-oncogene C-KIT in a sample of Australian cutaneous canine mast cell tumours (MCTs) drawn from general practice and to evaluate relationships between tumour mutation status and prognostic factors including signalment, tumour histological grade, tumour anatomical location and tumour size. C-KIT exon 11 ITDs were detected by PCR in DNA extracted from formalin-fixed, paraffin-embedded canine MCTs sourced from three veterinary diagnostic laboratories in Adelaide and Melbourne. Tumours were graded according to two different systems (Patnaik and Kiupel systems) by board-certified anatomical pathologists blinded to the PCR results. Relationships between tumour mutation status and prognostic factors were evaluated using a generalised binary logistic regression analysis. ITDs were identified in 13 of 74 cutaneous canine MCT samples, giving an overall prevalence of 17.6% (95% confidence interval: 8.9-26.2%). ITDs were detected in 10 of 18 Patnaik grade III MCTs (55.6%) and 11 of 22 Kiupel high-grade MCTs (50%). Wald chi-square analysis revealed that detection of tumour ITDs was significantly associated with both Patnaik's and Kiupel's histologic grading systems (each: P < 0.001). The presence of the ITDs in MCTs was not associated with signalment, tumour anatomical location or tumour size. The prevalence of C-KIT exon 11 ITDs in Australian canine MCTs is similar to the prevalence in overseas canine populations (overall prevalence in Australia approximately 18%). ITDs were more frequently identified in higher grade MCTs. © 2017 Australian Veterinary Association.

Management approach and surgical strategies for retrorectal tumours: a systematic review.

PubMed

Toh, J W T; Morgan, M

2016-04-01

The management strategy for retrorectal tumours is complex. Due to their rarity, few surgeons have expertise in management. A systematic literature review was conducted using the PubMed database. English language publications in the years 2011-2015 that assessed preoperative management, surgical strategies and chemoradiotherapy for presacral tumours were included. Two hundred and fifty-one abstracts were screened of which 88 met the inclusion criteria. After review of the full text, this resulted in a final list of 42 studies eligible for review. In all, 932 patients (63.2% female, 36.8% male; P < 0.01) with a retrorectal tumour were identified. Most were benign (65.9% vs. 33.7%, P < 0.01). Imaging distinguished benign from malignant lesions in 88.1% of cases; preoperative biopsy was superior to imaging in providing an accurate definitive diagnosis (91.3% vs. 61.4%, P < 0.05) with negligible seeding risk. Biopsy should be performed in solid tumours. It is useful in guiding neoadjuvant therapy for gastrointestinal stromal tumours, sarcomas and desmoid type fibromatosis and may alter the management strategy in cases of diffuse large B-cell lymphoma and metastases. Biopsies for cystic lesions are not recommended. The gold standard in imaging is MRI. The posterior Kraske procedure is the most common surgical approach. Overall, the reported recurrence rate was 19.7%. This review evaluated the management strategies for retrorectal tumours. A preoperative biopsy should be performed for solid tumours. MRI is the most useful imaging modality. Surgery is the mainstay of treatment. There is limited information on robotic surgery, single-port surgery, transanal endoscopic microsurgery, chemoradiotherapy and reconstruction. Colorectal Disease © 2015 The Association of Coloproctology of Great Britain and Ireland.

Optimising the combination dosing strategy of abemaciclib and vemurafenib in BRAF-mutated melanoma xenograft tumours.

PubMed

Tate, Sonya C; Burke, Teresa F; Hartman, Daisy; Kulanthaivel, Palaniappan; Beckmann, Richard P; Cronier, Damien M

2016-03-15

Resistance to BRAF inhibition is a major cause of treatment failure for BRAF-mutated metastatic melanoma patients. Abemaciclib, a cyclin-dependent kinase 4 and 6 inhibitor, overcomes this resistance in xenograft tumours and offers a promising drug combination. The present work aims to characterise the quantitative pharmacology of the abemaciclib/vemurafenib combination using a semimechanistic pharmacokinetic/pharmacodynamic modelling approach and to identify an optimum dosing regimen for potential clinical evaluation. A PK/biomarker model was developed to connect abemaciclib/vemurafenib concentrations to changes in MAPK and cell cycle pathway biomarkers in A375 BRAF-mutated melanoma xenografts. Resultant tumour growth inhibition was described by relating (i) MAPK pathway inhibition to apoptosis, (ii) mitotic cell density to tumour growth and, under resistant conditions, (iii) retinoblastoma protein inhibition to cell survival. The model successfully described vemurafenib/abemaciclib-mediated changes in MAPK pathway and cell cycle biomarkers. Initial tumour shrinkage by vemurafenib, acquisition of resistance and subsequent abemaciclib-mediated efficacy were successfully captured and externally validated. Model simulations illustrate the benefit of intermittent vemurafenib therapy over continuous treatment, and indicate that continuous abemaciclib in combination with intermittent vemurafenib offers the potential for considerable tumour regression. The quantitative pharmacology of the abemaciclib/vemurafenib combination was successfully characterised and an optimised, clinically-relevant dosing strategy was identified.

Suppressor Analysis Reveals a Role for SecY in the SecA2-Dependent Protein Export Pathway of Mycobacteria

PubMed Central

Ligon, Lauren S.; Rigel, Nathan W.; Romanchuk, Artur; Jones, Corbin D.

2013-01-01

All bacteria use the conserved Sec pathway to transport proteins across the cytoplasmic membrane, with the SecA ATPase playing a central role in the process. Mycobacteria are part of a small group of bacteria that have two SecA proteins: the canonical SecA (SecA1) and a second, specialized SecA (SecA2). The SecA2-dependent pathway exports a small subset of proteins and is required for Mycobacterium tuberculosis virulence. The mechanism by which SecA2 drives export of proteins across the cytoplasmic membrane remains poorly understood. Here we performed suppressor analysis on a dominant negative secA2 mutant (secA2 K129R) of the model mycobacterium Mycobacterium smegmatis to better understand the pathway used by SecA2 to export proteins. Two extragenic suppressor mutations were identified as mapping to the promoter region of secY, which encodes the central component of the canonical Sec export channel. These suppressor mutations increased secY expression, and this effect was sufficient to alleviate the secA2 K129R phenotype. We also discovered that the level of SecY protein was greatly diminished in the secA2 K129R mutant, but at least partially restored in the suppressors. Furthermore, the level of SecY in a suppressor strongly correlated with the degree of suppression. Our findings reveal a detrimental effect of SecA2 K129R on SecY, arguing for an integrated system in which SecA2 works with SecY and the canonical Sec translocase to export proteins. PMID:23913320

Relationship of serum CEA levels to tumour size and CEA content in nude mice bearing colonic-tumour xenografts.

PubMed Central

Lewis, J. C.; Keep, P. A.

1981-01-01

The relationship of serum carcinoembryonic antigen (CEA) levels to tumour size and antigen content was studied in nude mice bearing well differentiated, mucinous human colonic-tumour xenografts. Blood samples were taken from normal nude mice and others bearing xenografts, whose size had been calculated from in vivo measurements; saline and KCl extracts were made of a proportion of these tumours. Sera and tissue extracts were assayed for CEA activity by double-antibody radioimmunoassay. Extracts were also made from the livers and spleens of tumour-bearing and normal nude mice. All normal sera and 78% of sera from tumour-bearing animals had CEA values less than 11.4 ng/ml. No clear correlation was found between serum CEA levels greater than 11.4 ng/ml and tumour size or weight, or between serum CEA and tumour CEA concentrations or total CEA burden. The concentration of CEA in those tumours tested varied from 1 to 22 microgram/g. Our results confirm and extend the conclusions reached by others (Stragand et al., 1980) studying the significance of serum CEA levels with xenograft model systems. The complexity of factors contributing to circulating CEA is discussed in the light of our findings. Images Fig. 1 PMID:7284235

Analysis of the structure of fish lymphocystis disease virions from skin tumours of pleuronectes.

PubMed

Samalecos, C P

1986-01-01

Virions of fish lymphocystis disease (FLDV) from tumour-carrying-fishes (flounder, dab, plaice and gurnard) collected in the North Sea were isolated directly from the tumours and purified by sucrose and subsequent caesium chloride gradient centrifugation. They were studied by electron microscopy using embedding methods, negative staining and using metal shadowing methods. Tumours of dermal connective fish tissue showed particles with hexagonal outlines. Occasionally, an "empty structure" was observed. Subunits of the virus membrane were identified after 3 per cent phosphotungstic acid (PTA) or 0.2 per cent Ruthenium red (RR) staining. FLDV measures 199-227 nm in diameter.

Tropomyosin Receptor Antagonism in Cylindromatosis (TRAC), an early phase trial of a topical tropomyosin kinase inhibitor as a treatment for inherited CYLD defective skin tumours: study protocol for a randomised controlled trial.

PubMed

Cranston, Amy; Stocken, Deborah D; Stamp, Elaine; Roblin, David; Hamlin, Julia; Langtry, James; Plummer, Ruth; Ashworth, Alan; Burn, John; Rajan, Neil

2017-03-07

Patients with germline mutations in a tumour suppressor gene called CYLD develop multiple, disfiguring, hair follicle tumours on the head and neck. The prognosis is poor, with up to one in four mutation carriers requiring complete surgical removal of the scalp. There are no effective medical alternatives to treat this condition. Whole genome molecular profiling experiments led to the discovery of an attractive molecular target in these skin tumour cells, named tropomyosin receptor kinase (TRK), upon which these cells demonstrate an oncogenic dependency in preclinical studies. Recently, the development of an ointment containing a TRK inhibitor (pegcantratinib - previously CT327 - from Creabilis SA) allowed for the assessment of TRK inhibition in tumours from patients with inherited CYLD mutations. Tropomysin Receptor Antagonism in Cylindromatosis (TRAC) is a two-part, exploratory, early phase, single-centre trial. Cohort 1 is a phase 1b open-labelled trial, and cohort 2 is a phase 2a randomised double-blinded exploratory placebo-controlled trial. Cohort 1 will determine the safety and acceptability of applying pegcantratinib for 4 weeks to a single tumour on a CYLD mutation carrier that is scheduled for a routine lesion excision (n = 8 patients). Cohort 2 will investigate if CYLD defective tumours respond following 12 weeks of treatment with pegcantratinib. As patients have multiple tumours, we intend to treat 10 tumours in each patient, 5 with active treatment and 5 with placebo. Patients will be allocated both active and placebo treatments to be applied randomly to tumours on the left or right side. The target is to treat 150 tumours in a maximum of 20 patients. Tumour volume will be measured at baseline and at 4 and 12 weeks. The primary outcome measure is the proportion of tumours responding to treatment by 12 weeks, based on change in tumour volume, with secondary measures based on adverse event profile, treatment compliance and acceptability, changes

The retinoblastoma gene is frequently altered leading to loss of expression in primary breast tumours.

PubMed

Varley, J M; Armour, J; Swallow, J E; Jeffreys, A J; Ponder, B A; T'Ang, A; Fung, Y K; Brammar, W J; Walker, R A

1989-06-01

We have analysed the organisation of the retinoblastoma (RB1) gene in 77 primary breast carcinomas, in metastatic tissue derived from 16 of those primary tumours, and in a variety of benign breast lesions. Expression of RB1 was also assessed in most samples by immunohistochemical detection of the RB1 protein in tissue sections. Structural abnormalities to RB1 were detected in DNA from 15/77 (19%) of primary breast carcinomas examined. Where DNA was available from metastatic tissue derived from such primary tumours, the same aberration could be detected. No alterations were seen in benign breast lesions. 16/56 (29%) of tumours examined for expression by immunohistochemical methods showed a proportion of tumour cells to be completely negative for the RB1 protein. All tumours in which a structural alteration to RB1 was detected had a proportion of negative cells, except for one case where all cells were positive. Several primary tumour samples were identified where there was no detectable structural change to the gene, but there was loss of expression in some tumour cells. The data presented here demonstrate that changes to the RB1 gene leading to loss of expression of both alleles are frequent in primary human breast tumours.

Pancreatic tumours produce neurotensin.

PubMed

Blackburn, A M; Bryant, M G; Adrian, T E; Bloom, S R

1981-04-01

Tumour tissue may secrete substances which are not normally secreted by the original tissue. We have found that 6 out of 21 pancreatic tumours producing vasoactive intestinal peptide also produce neurotensin-like peptides. These are sometimes secreted and very high plasma levels of neurotensin-like immunoreactivity may be found in the circulation.

Tumour-derived SPARC drives vascular permeability and extravasation through endothelial VCAM1 signalling to promote metastasis.

PubMed

Tichet, Mélanie; Prod'Homme, Virginie; Fenouille, Nina; Ambrosetti, Damien; Mallavialle, Aude; Cerezo, Michael; Ohanna, Mickaël; Audebert, Stéphane; Rocchi, Stéphane; Giacchero, Damien; Boukari, Fériel; Allegra, Maryline; Chambard, Jean-Claude; Lacour, Jean-Philippe; Michiels, Jean-François; Borg, Jean-Paul; Deckert, Marcel; Tartare-Deckert, Sophie

2015-04-30

Disruption of the endothelial barrier by tumour-derived secreted factors is a critical step in cancer cell extravasation and metastasis. Here, by comparative proteomic analysis of melanoma secretomes, we identify the matricellular protein SPARC as a novel tumour-derived vascular permeability factor. SPARC deficiency abrogates tumour-initiated permeability of lung capillaries and prevents extravasation, whereas SPARC overexpression enhances vascular leakiness, extravasation and lung metastasis. SPARC-induced paracellular permeability is dependent on the endothelial VCAM1 receptor and p38 MAPK signalling. Blocking VCAM1 impedes melanoma-induced endothelial permeability and extravasation. The clinical relevance of our findings is highlighted by high levels of SPARC detected in tumour from human pulmonary melanoma lesions. Our study establishes tumour-produced SPARC and VCAM1 as regulators of cancer extravasation, revealing a novel targetable interaction for prevention of metastasis.

Tumours of the lower alimentary tract

PubMed Central

Head, K. W.

1976-01-01

This classification is presented in two parts: (a) tumours of the gastrointestinal tract; and (b) tumours of the anal canal and margin. In the gastrointestinal tract the tumours are classified as adenoma, adenocarcinoma, and undifferentiated carcinoma, with several subtypes. Most polyps prove to be non-neoplastic, hyperplastic, or regenerative rather than adenomatous. Carcinoma of the stomach occurs mainly in dogs, but is a rare tumour in all parts of the world. Moderately differentiated, tubular adenocarcinoma of the small intestine with excessive fibrosis occurs in all six species; in some geographical locations it may occur frequently in sheep and cattle. The adenoma/carcinoma sequence in the rectum of the dog is similar to that in man but is encountered less often. Carcinoid tumours are very rare in domestic animals. Among the soft tissue tumours, those of smooth muscle and adipose tissue are found fairly frequently and congenital mesothelioma in the peritoneum of calves occurs occasionally. Tumours of the haematopoietic and related tissues are the most common gastrointestinal neoplasms in all species and most belong to the lymphosarcoma group. Tumours of the anal canal and margin are common in the dog and 90% of these are tumours of the hepatoid (perianal) glands. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 29Fig. 30Fig. 31Fig. 32Fig. 33Fig. 34Fig. 35Fig. 36Fig. 13Fig. 14Fig. 15Fig. 16Fig. 9Fig. 10Fig. 11Fig. 12Fig. 5Fig. 6Fig. 7Fig. 8Fig. 37Fig. 38Fig. 39Fig. 40Fig. 25Fig. 26Fig. 27Fig. 28Fig. 17Fig. 18Fig. 19Fig. 20Fig. 21Fig. 22Fig. 23Fig. 24 PMID:1086148

Renal and adrenal tumours in children

PubMed Central

2007-01-01

The differential diagnosis of renal and supra-renal masses firstly depends on the age of the child. Neuroblastoma (NBL) may be seen antenatally or in the newborn period; this tumour has a good prognosis unlike NBL seen in older children (particularly NBL in those aged 2–4 years). Benign renal masses predominate in early infancy but beyond the first year of life Wilms' tumour is the most common renal malignancy, until adolescence when renal cell carcinoma has similar or increased frequency as children get older. Adrenal adenomas and carcinomas also occur in childhood; these tumours are indistinguishable on imaging but criteria for the diagnosis of adrenal carcinoma include size larger than 5 cm, a tendency to invade the inferior vena cava and to metastasise. The most topical dilemmas in the radiological assessment of renal and adrenal tumours are presented. Topics covered include a proposed revision to the staging of NBL, the problems inherent in distinguishing nephrogenic rests from Wilms' tumour and the current recently altered approach regarding small lung nodules in children with Wilms' tumour. PMID:17339140

Switching on RNA Silencing Suppressor Activity by Restoring Argonaute Binding to a Viral Protein

PubMed Central

Szabó, Edit Z.; Manczinger, Máté; Göblös, Anikó; Kemény, Lajos

2012-01-01

We found that Sweet potato feathery mottle virus (SPFMV) P1, a close homologue of Sweet potato mild mottle virus P1, did not have any silencing suppressor activity. Remodeling the Argonaute (AGO) binding domain of SPFMV P1 by the introduction of two additional WG/GW motifs converted it to a silencing suppressor with AGO binding capacity. To our knowledge, this is the first instance of the transformation of a viral protein of unknown function to a functional silencing suppressor. PMID:22623784

Functional analysis of a weak viral RNA silencing suppressor using two GFP variants as silencing inducers.

PubMed

Mann, Krin S; Dietzgen, Ralf G

2017-01-01

RNA silencing in plants can be triggered by the introduction of an exogenous gene. Green fluorescent protein (GFP) has been widely used as a visual reporter to study RNA silencing and viral-mediated suppression of RNA silencing in the model plant Nicotiana benthamiana. In transgenic N. benthamiana plants expressing an endoplasmic reticulum targeted GFP variant (16c) known as mGFP5, RNA silencing can be induced by ectopic over-expression of mGFP5. However, other GFP variants can also be used to induce GFP silencing in these plants. We compared the efficiency to induce local and systemic silencing of two commonly used GFP variants: enhanced GFP (eGFP) and mGFP5. Using lettuce necrotic yellows virus (LNYV) P protein to suppress GFP silencing, we demonstrate that eGFP gene, which is 76% identical at the nucleotide level to the endogenously expressed mGFP5 in 16c plants, triggers silencing more slowly and concurrently prolongs detectable silencing suppressor activity of the weak LNYV P suppressor, compared to the homologous mGFP5 gene. The use of eGFP as RNA silencing inducer in wild type or 16c plants appears to be a useful tool in identifying and analysing weak viral RNA silencing suppressor proteins whose activity might otherwise have been masked when challenged by a stronger RNA silencing response. We also show that reducing the dosage of strong dsRNA silencing inducers in conjunction with their homologous GFP targets facilitates the discovery and analysis of "weaker" RNA silencing suppressor activities. Copyright © 2016 Elsevier B.V. All rights reserved.

Morphology and genomic hallmarks of breast tumours developed by ATM deleterious variant carriers.

PubMed

Renault, Anne-Laure; Mebirouk, Noura; Fuhrmann, Laetitia; Bataillon, Guillaume; Cavaciuti, Eve; Le Gal, Dorothée; Girard, Elodie; Popova, Tatiana; La Rosa, Philippe; Beauvallet, Juana; Eon-Marchais, Séverine; Dondon, Marie-Gabrielle; d'Enghien, Catherine Dubois; Laugé, Anthony; Chemlali, Walid; Raynal, Virginie; Labbé, Martine; Bièche, Ivan; Baulande, Sylvain; Bay, Jacques-Olivier; Berthet, Pascaline; Caron, Olivier; Buecher, Bruno; Faivre, Laurence; Fresnay, Marc; Gauthier-Villars, Marion; Gesta, Paul; Janin, Nicolas; Lejeune, Sophie; Maugard, Christine; Moutton, Sébastien; Venat-Bouvet, Laurence; Zattara, Hélène; Fricker, Jean-Pierre; Gladieff, Laurence; Coupier, Isabelle; Chenevix-Trench, Georgia; Hall, Janet; Vincent-Salomon, Anne; Stoppa-Lyonnet, Dominique; Andrieu, Nadine; Lesueur, Fabienne

2018-04-17

characteristics and genomic alterations, and they are also distinguishable from sporadic breast tumours, thus opening up the possibility to identify ATM variant carriers outside the ataxia-telangiectasia disorder and direct them towards effective cancer risk management and therapeutic strategies.

Multicystic dedifferentiated retroperitoneal liposarcoma: tumour cyst fluid analysis and implications for management.

PubMed

Khoury, Mitri; Sim, Geok Choo; Harao, Michiko; Radvanyi, Laszlo; Amini, Behrang; Benjamin, Robert S; Pisters, Peter W T; Pollock, Raphael E; Tseng, William W

2015-07-08

Liposarcomas are soft tissue sarcomas of adipocyte origin. We describe a case of a dedifferentiated retroperitoneal liposarcoma with an unusual presentation on recurrence as a large, multicystic tumour. The patient was a 72-year-old woman who had undergone multiple treatments including two prior resections. For her most recent locoregional disease recurrence, the patient was offered surgical debulking for symptom palliation. At this operation, performed after two cycles of chemotherapy, the tumour cyst fluid was analysed and found to have a predominance of immune cells with no identifiable malignant cells. This case and the results of our tumour cyst fluid analysis raise several interesting considerations for the management of this unique situation in a rare disease. 2015 BMJ Publishing Group Ltd.

Investigating intracranial tumour growth patterns with multiparametric MRI incorporating Gd-DTPA and USPIO-enhanced imaging.

PubMed

Boult, Jessica K R; Borri, Marco; Jury, Alexa; Popov, Sergey; Box, Gary; Perryman, Lara; Eccles, Suzanne A; Jones, Chris; Robinson, Simon P

2016-11-01

High grade and metastatic brain tumours exhibit considerable spatial variations in proliferation, angiogenesis, invasion, necrosis and oedema. Vascular heterogeneity arising from vascular co-option in regions of invasive growth (in which the blood-brain barrier remains intact) and neoangiogenesis is a major challenge faced in the assessment of brain tumours by conventional MRI. A multiparametric MRI approach, incorporating native measurements and both Gd-DTPA (Magnevist) and ultrasmall superparamagnetic iron oxide (P904)-enhanced imaging, was used in combination with histogram and unsupervised cluster analysis using a k-means algorithm to examine the spatial distribution of vascular parameters, water diffusion characteristics and invasion in intracranially propagated rat RG2 gliomas and human MDA-MB-231 LM2-4 breast adenocarcinomas in mice. Both tumour models presented with higher ΔR 1 (the change in transverse relaxation rate R 1 induced by Gd-DTPA), fractional blood volume (fBV) and apparent diffusion coefficient than uninvolved regions of the brain. MDA-MB-231 LM2-4 tumours were less densely cellular than RG2 tumours and exhibited substantial local invasion, associated with oedema, whereas invasion in RG2 tumours was minimal. These additional features were reflected in the more heterogeneous appearance of MDA-MB-231 LM2-4 tumours on T 2 -weighted images and maps of functional MRI parameters. Unsupervised cluster analysis separated subregions with distinct functional properties; areas with a low fBV and relatively impermeable blood vessels (low ΔR 1 ) were predominantly located at the tumour margins, regions of MDA-MB-231 LM2-4 tumours with relatively high levels of water diffusion and low vascular permeability and/or fBV corresponded to histologically identified regions of invasion and oedema, and areas of mismatch between vascular permeability and blood volume were identified. We demonstrate that dual contrast MRI and evaluation of tissue diffusion properties

Optic nerve gliomas: role of Ki-67 staining of tumour and margins in predicting long-term outcome.

PubMed

Yeung, Sonia N; White, Valerie A; Nimmo, Michael; Rootman, Jack

2011-08-01

Although optic nerve gliomas (ONGs) are generally slow-growing with a good prognosis, factors for identifying cases that may pursue a more aggressive course are not well established. The authors investigated cell proliferation markers for prognostic significance in a series of resected ONGs. Twelve cases of resected ONG were identified out of a total of 38 examined at the authors' institution between 1981 and 2008. Clinical data were reviewed. Ki-67 and p53 immunohistochemical staining was performed on the tumour mass and the proximal resection margin. All of the tumours were low-grade pilocytic astrocytomas. Six patients were suspected to have histologically positive proximal resection margins. Ki-67 labelling indices (LI) ranged from 0.3% to 5.9% (mean 2.4%) for the tumour mass and from 0 to 2.1% (mean 0.9%) for the proximal resection margins. One patient had evidence of progression 25 months after subtotal surgical resection. The Ki-67 LI of the proximal resection margin in this case was similar to the main tumour value. The other six patients with histologically negative proximal resection margins all had lower relative proliferation indices at the resection margin when compared with the tumour mass and are currently stable with no evidence of progression. Routine histological examination of resection margins may be difficult to interpret in the setting of reactive gliosis. A resection margin with a Ki-67 LI similar to the tumour bulk value may have an adjunctive role in identifying cases with the potential for growth thereby facilitating the decision-making process for future management and surveillance.

Targeting of the tumor suppressor GRHL3 by a miR-21-dependent proto-oncogenic network results in PTEN loss and tumorigenesis.

PubMed

Darido, Charbel; Georgy, Smitha R; Wilanowski, Tomasz; Dworkin, Sebastian; Auden, Alana; Zhao, Quan; Rank, Gerhard; Srivastava, Seema; Finlay, Moira J; Papenfuss, Anthony T; Pandolfi, Pier Paolo; Pearson, Richard B; Jane, Stephen M

2011-11-15

Despite its prevalence, the molecular basis of squamous cell carcinoma (SCC) remains poorly understood. Here, we identify the developmental transcription factor Grhl3 as a potent tumor suppressor of SCC in mice, and demonstrate that targeting of Grhl3 by a miR-21-dependent proto-oncogenic network underpins SCC in humans. Deletion of Grhl3 in adult epidermis evokes loss of expression of PTEN, a direct GRHL3 target, resulting in aggressive SCC induced by activation of PI3K/AKT/mTOR signaling. Restoration of Pten expression completely abrogates SCC formation. Reduced levels of GRHL3 and PTEN are evident in human skin, and head and neck SCC, associated with increased expression of miR-21, which targets both tumor suppressors. Our data define the GRHL3-PTEN axis as a critical tumor suppressor pathway in SCC. 2011 Elsevier Inc. All rights reserved.

The Polerovirus silencing suppressor P0 targets ARGONAUTE proteins for degradation.

PubMed

Baumberger, Nicolas; Tsai, Ching-Hsui; Lie, Miranda; Havecker, Ericka; Baulcombe, David C

2007-09-18

Plant and animal viruses encode suppressor proteins of an adaptive immunity mechanism in which viral double-stranded RNA is processed into 21-25 nt short interfering (si)RNAs. The siRNAs guide ARGONAUTE (AGO) proteins so that they target viral RNA. Most viral suppressors bind long dsRNA or siRNAs and thereby prevent production of siRNA or binding of siRNA to AGO. The one exception is the 2b suppressor of Cucumoviruses that binds to and inhibits AGO1. Here we describe a novel suppressor mechanism in which a Polerovirus-encoded F box protein (P0) targets the PAZ motif and its adjacent upstream sequence in AGO1 and mediates its degradation. F box proteins are components of E3 ubiquitin ligase complexes that add polyubiquitin tracts on selected lysine residues and thereby mark a protein for proteasome-mediated degradation. With P0, however, the targeted degradation of AGO is insensitive to inhibition of the proteasome, indicating that the proteasome is not involved. We also show that P0 does not block a mobile signal of silencing, indicating that the signal molecule does not have AGO protein components. The ability of P0 to block silencing without affecting signal movement may contribute to the phloem restriction of viruses in the Polerovirus group.

A pH-activatable nanoparticle with signal-amplification capabilities for non-invasive imaging of tumour malignancy.

PubMed

Mi, Peng; Kokuryo, Daisuke; Cabral, Horacio; Wu, Hailiang; Terada, Yasuko; Saga, Tsuneo; Aoki, Ichio; Nishiyama, Nobuhiro; Kataoka, Kazunori

2016-08-01

Engineered nanoparticles that respond to pathophysiological parameters, such as pH or redox potential, have been developed as contrast agents for the magnetic resonance imaging (MRI) of tumours. However, beyond anatomic assessment, contrast agents that can sense these pathological parameters and rapidly amplify their magnetic resonance signals are desirable because they could potentially be used to monitor the biological processes of tumours and improve cancer diagnosis. Here, we report an MRI contrast agent that rapidly amplifies magnetic resonance signals in response to pH. We confined Mn(2+) within pH-sensitive calcium phosphate (CaP) nanoparticles comprising a poly(ethylene glycol) shell. At a low pH, such as in solid tumours, the CaP disintegrates and releases Mn(2+) ions. Binding to proteins increases the relaxivity of Mn(2+) and enhances the contrast. We show that these nanoparticles could rapidly and selectively brighten solid tumours, identify hypoxic regions within the tumour mass and detect invisible millimetre-sized metastatic tumours in the liver.

A pH-activatable nanoparticle with signal-amplification capabilities for non-invasive imaging of tumour malignancy

NASA Astrophysics Data System (ADS)

Mi, Peng; Kokuryo, Daisuke; Cabral, Horacio; Wu, Hailiang; Terada, Yasuko; Saga, Tsuneo; Aoki, Ichio; Nishiyama, Nobuhiro; Kataoka, Kazunori

2016-08-01

Engineered nanoparticles that respond to pathophysiological parameters, such as pH or redox potential, have been developed as contrast agents for the magnetic resonance imaging (MRI) of tumours. However, beyond anatomic assessment, contrast agents that can sense these pathological parameters and rapidly amplify their magnetic resonance signals are desirable because they could potentially be used to monitor the biological processes of tumours and improve cancer diagnosis. Here, we report an MRI contrast agent that rapidly amplifies magnetic resonance signals in response to pH. We confined Mn2+ within pH-sensitive calcium phosphate (CaP) nanoparticles comprising a poly(ethylene glycol) shell. At a low pH, such as in solid tumours, the CaP disintegrates and releases Mn2+ ions. Binding to proteins increases the relaxivity of Mn2+ and enhances the contrast. We show that these nanoparticles could rapidly and selectively brighten solid tumours, identify hypoxic regions within the tumour mass and detect invisible millimetre-sized metastatic tumours in the liver.

Metformin treatment modulates the tumour-induced wasting effects in muscle protein metabolism minimising the cachexia in tumour-bearing rats.

PubMed

Oliveira, André G; Gomes-Marcondes, Maria Cristina C

2016-07-07

Cancer-cachexia state frequently induces both fat and protein wasting, leading to death. In this way, the knowledge of the mechanism of drugs and their side effects can be a new feature to treat and to have success, contributing to a better life quality for these patients. Metformin is an oral drug used in type 2 diabetes mellitus, showing inhibitory effect on proliferation in some neoplastic cells. For this reason, we evaluated its modulatory effect on Walker-256 tumour evolution and also on protein metabolism in gastrocnemius muscle and body composition. Wistar rats received or not tumour implant and metformin treatment and were distributed into four groups, as followed: control (C), Walker 256 tumour-bearing (W), metformin-treated (M) and tumour-bearing treated with metformin (WM). Animals were weighed three times a week, and after cachexia state has been detected, the rats were euthanised and muscle and tumour excised and analysed by biochemical and molecular assays. Tumour growth promoted some deleterious effects on chemical body composition, increasing water and decreasing fat percentage, and reducing lean body mass. In muscle tissue, tumour led to a decreased protein synthesis and an increased proteolysis, showing the higher activity of the ubiquitin-proteasome pathway. On the other hand, the metformin treatment likely minimised the tumour-induced wasting state; in this way, this treatment ameliorated chemical body composition, reduced the higher activities of proteolytic enzymes and decreased the protein waste. Metformin treatment not only decreases the tumour growth but also improves the protein metabolism in gastrocnemius muscle in tumour-bearing rats.

NNMT silencing activates tumor suppressor PP2A, inactivates oncogenic STKs and inhibits tumor forming ability

PubMed Central

Palanichamy, Kamalakannan; Kanji, Suman; Gordon, Nicolaus; Thirumoorthy, Krishnan; Jacob, John R.; Litzenberg, Kevin T.; Patel, Disha; Chakravarti, Arnab

2016-01-01

Purpose To identify potential molecular hubs that regulate oncogenic kinases and target them to improve treatment outcomes for glioblastoma (GBM) patients. Experimental Design Data mining of The Cancer Genome Atlas (TCGA) datasets identified Nicotinamide-N-methyl transferase (NNMT) as a prognostic marker for GBM, an enzyme linked to the reorganization of the methylome. We tested our hypothesis that NNMT plays a crucial role by modulating protein methylation leading to inactivation of tumor suppressors and activation of oncogenes. Further experiments were performed to understand the underlying biochemical mechanisms using GBM patient samples, established, primary, and isogenic cells. Results We demonstrate that NNMT outcompetes leucine carboxyl methyl transferase 1 (LCMT1) for methyl transfer from principal methyl donor SAM in biological systems. Inhibiting NNMT increased the availability of methyl groups for LCMT1 to methylate PP2A, resulting in the inhibition of oncogenic serine/threonine kinases (STKs). Further, NNMT inhibition retained the radiosensitizer nicotinamide and enhanced radiation sensitivity. We have provided the biochemical rationale of how NNMT plays a vital role in inhibiting tumor suppressor PP2A while concomitantly activating STKs. Conclusion We report the intricate novel mechanism in which NNMT inhibits tumor suppressor PP2A by reorganizing the methylome both at epigenome and proteome levels and concomitantly activating pro-survival STKs. In GBM tumors with NNMT expression, activation of PP2A can be accomplished by FDA approved perphenazine (PPZ) which is currently used to treat mood disorders such as schizophrenia, bipolar disorder, etc. This study forms a foundation for further GBM clinical trials using PPZ with standard of care treatment. PMID:27810903

ERF is a Potential ERK Modulated Tumor Suppressor in Prostate Cancer

DTIC Science & Technology

2016-10-01

6/27/2016 - 6/27/2019 1.20 calendar Prostate Cancer Foundation (formerly CaP CURE) $ 75,000 Epigenetic ...AWARD NUMBER: W81XWH-15-1-0277 TITLE: ERF is a Potential ERK-Modulated Tumor Suppressor in Prostate Cancer PRINCIPAL INVESTIGATOR: Dr. Rohit...4. TITLE AND SUBTITLE ERF is a Potential ERK-Modulated Tumor Suppressor in Prostate Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-1-0277

Endometrial endometrioid adenocarcinoma associated with primitive neuroectodermal tumour of the uterus: a poor prognostic subtype of uterine tumours.

PubMed

Bartosch, Carla; Vieira, Joana; Teixeira, Manuel R; Lopes, José Manuel

2011-12-01

Uterine primitive neuroectodermal tumours are extremely rare tumours. They can occur in pure form or combined with another component including endometrioid adenocarcinoma. We aimed to review the clinical impact of neuroectodermal phenotype in uterine tumours, after we recently diagnosed one such case. A 58-year-old female presented with irregular vaginal bleeding. Ultrasonography and CT showed the presence of a large uterine mass with irregular contours. At laparotomy it was found to extend to the right ureter, sigmoid colon and some small intestinal loops. Microscopic examination revealed that the tumour consisted of an endometrioid adenocarcinoma component merging with an extensive neuroectodermal component. No EWSR1 or FUS rearrangement was found in the two tumour components. The patient received two courses of chemotherapy but died 11 months after the initial diagnosis. We reviewed the morphological and molecular criteria for the diagnosis of uterine primitive neuroectodermal tumours published in the literature. We conclude that regardless of the detection of an EWSR1 rearrangement, the presence of a neuroectodermal differentiation component in these rare uterine tumours is a marker of aggressive behaviour, and its presence should be highlighted in the diagnosis.

Surgical approach to pineal tumours.

PubMed

Pluchino, F; Broggi, G; Fornari, M; Franzini, A; Solero, C L; Allegranza, A

1989-01-01

During a period of 10 years (1977-1986) 40 cases of tumour of the pineal region have been treated at the Istituto Neurologico "C. Besta"-of Milan. Out of these 40 cases, 27 (67.5%) were in the paediatric (10-15 years) or juvenile (15-20 years) age at the time of operation. Since 1983 a specific diagnostic and therapeutic protocol has been adopted and thereafter direct surgical removal of the tumour was performed only when the neuroradiological investigations were highly suggestive of a benign extrinsic lesion. Sixteen cases in this series underwent direct surgical removal; in the remaining 24 cases stereotactic biopsy of the tumour was performed in the first instance. On the basis of the histological diagnosis obtained by this procedure surgical excision of the tumour (9 cases) or radiotherapy (15 cases) was then performed. 25 cases underwent surgical removal of the lesion. In all the cases the infratentorial supracerebellar approach as introduced by Krause and then modified by Stein was adopted. On analysis of the data of this series it was observed that in 25% of the cases completely benign resectable tumours were found; in 25% of the cases astrocytoma (grade I-II) which could be treated at least by partial removal were present; in 30% of the cases radiosensitive lesions were encountered. In the remaining 20% of the cases highly malignant tumours were found which should be treated only by radiotherapy and/or chemotherapy.

Synchronous tumours of the female reproductive tract.

PubMed

Gilks, C Blake; Kommoss, Friedrich

2018-02-01

Many ovarian endometrioid carcinomas present with concurrent endometrial carcinoma, and these organ-confined, low-grade synchronous endometrial and ovarian tumours consistently behave as independent primary tumours, rather than a single advanced-stage carcinoma; they are associated with a very favourable prognosis and there is no need for adjuvant treatment. This phenomenon of synchronous tumours involving two or more sites within the female reproductive tract is well recognised, occurring in 1-2% of cases. Although some tumours can be recognised as metastasis, in many the relationship between the synchronous tumours is uncertain. Recently, application of next generation sequencing to synchronous endometrial and ovarian carcinomas has shed light on the relationship between these tumours, but raised more questions about the biology of this curious phenomenon. Herein, we review synchronous tumours involving more than one site in the female genital tract, discuss the pathogenesis, and offer guidelines for how to handle in routine practice. Copyright © 2017 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.

Radiological and pathological features associated with IDH1-R132H mutation status and early mortality in newly diagnosed anaplastic astrocytic tumours.

PubMed

Wasserman, Jason K; Nicholas, Garth; Yaworski, Rebecca; Wasserman, Anne-Marie; Woulfe, John M; Jansen, Gerard H; Chakraborty, Santanu; Nguyen, Thanh B

2015-01-01

Glioblastoma can occur either de novo or by the transformation of a low grade tumour; the majority of which harbor a mutation in isocitrate dehydrogenase (IDH1). Anaplastic tumours are high-grade gliomas that may represent the final step in the evolution of a secondary glioblastoma or the initial presentation of an early primary glioblastoma. We sought to determine whether pathological and/or radiological variables exist that can reliably distinguish IDH1-R132H-positive from IDH1-R132H-negative tumours and to identify variables associated with early mortality. Patients diagnosed with anaplastic astrocytic tumours were included. Magnetic resonance imaging was performed and immunohistochemistry was used to identify tumours with the IDH1-R132H mutation. Survival was assessed 12 months after diagnosis. Variables associated with IDH1-R132H status were identified by univariate and ROC analysis. 37 gliomas were studied; 18 were positive for the IDH1-R132H mutation. No tumours demonstrated a combined loss of chromosomes 1p/19q. Patients with IDH1-R132H-positive tumours were less likely to die within 12 months of diagnosis (17% vs. 47%; p=0.046), more likely to have tumours located in the frontal lobe (55% vs. 16%; p=0.015), and have a higher minimum apparent diffusion coefficient (1.115 x 10-3 mm2/sec vs. 0.838 x 10-3 mm2/sec; p=0.016), however, these variables demonstrated only moderate strength for predicting the IDH1-R132H mutation status (AUC=0.735 and 0.711, respectively). The Ki-67 index was significantly lower in IDH1-R132H-positive tumours (0.13 vs. 0.21; p=0.034). An increased risk of death was associated with contrast-enhancement ≥ 5 cm3 in patients with IDH1-R132H-positive tumours while edema ≥ 1 cm beyond the tumour margin and < 5 mitoses/mm2 were associated with an increased risk of death in patients with IDH1-R132H-negative tumours. IDH1-R132H-positive and -negative anaplastic tumours demonstrate unique features. Factors associated with early mortality

Radiological and Pathological Features Associated with IDH1-R132H Mutation Status and Early Mortality in Newly Diagnosed Anaplastic Astrocytic Tumours

PubMed Central

Wasserman, Jason K.; Nicholas, Garth; Yaworski, Rebecca; Wasserman, Anne-Marie; Woulfe, John M.; Jansen, Gerard H.; Chakraborty, Santanu; Nguyen, Thanh B.

2015-01-01

Background Glioblastoma can occur either de novo or by the transformation of a low grade tumour; the majority of which harbor a mutation in isocitrate dehydrogenase (IDH1). Anaplastic tumours are high-grade gliomas that may represent the final step in the evolution of a secondary glioblastoma or the initial presentation of an early primary glioblastoma. We sought to determine whether pathological and/or radiological variables exist that can reliably distinguish IDH1-R132H-positive from IDH1-R132H-negative tumours and to identify variables associated with early mortality. Methods Patients diagnosed with anaplastic astrocytic tumours were included. Magnetic resonance imaging was performed and immunohistochemistry was used to identify tumours with the IDH1-R132H mutation. Survival was assessed 12 months after diagnosis. Variables associated with IDH1-R132H status were identified by univariate and ROC analysis. Results 37 gliomas were studied; 18 were positive for the IDH1-R132H mutation. No tumours demonstrated a combined loss of chromosomes 1p/19q. Patients with IDH1-R132H-positive tumours were less likely to die within 12 months of diagnosis (17% vs. 47%; p=0.046), more likely to have tumours located in the frontal lobe (55% vs. 16%; p=0.015), and have a higher minimum apparent diffusion coefficient (1.115 x 10-3 mm2/sec vs. 0.838 x 10-3 mm2/sec; p=0.016), however, these variables demonstrated only moderate strength for predicting the IDH1-R132H mutation status (AUC=0.735 and 0.711, respectively). The Ki-67 index was significantly lower in IDH1-R132H-positive tumours (0.13 vs. 0.21; p=0.034). An increased risk of death was associated with contrast-enhancement ≥ 5 cm3 in patients with IDH1-R132H-positive tumours while edema ≥ 1 cm beyond the tumour margin and < 5 mitoses/mm2 were associated with an increased risk of death in patients with IDH1-R132H-negative tumours. Conclusions IDH1-R132H-positive and -negative anaplastic tumours demonstrate unique features

Targeting renal cell carcinoma with a HIF-2 antagonist.

PubMed

Chen, Wenfang; Hill, Haley; Christie, Alana; Kim, Min Soo; Holloman, Eboni; Pavia-Jimenez, Andrea; Homayoun, Farrah; Ma, Yuanqing; Patel, Nirav; Yell, Paul; Hao, Guiyang; Yousuf, Qurratulain; Joyce, Allison; Pedrosa, Ivan; Geiger, Heather; Zhang, He; Chang, Jenny; Gardner, Kevin H; Bruick, Richard K; Reeves, Catherine; Hwang, Tae Hyun; Courtney, Kevin; Frenkel, Eugene; Sun, Xiankai; Zojwalla, Naseem; Wong, Tai; Rizzi, James P; Wallace, Eli M; Josey, John A; Xie, Yang; Xie, Xian-Jin; Kapur, Payal; McKay, Renée M; Brugarolas, James

2016-11-03

Clear cell renal cell carcinoma (ccRCC) is characterized by inactivation of the von Hippel-Lindau tumour suppressor gene (VHL). Because no other gene is mutated as frequently in ccRCC and VHL mutations are truncal, VHL inactivation is regarded as the governing event. VHL loss activates the HIF-2 transcription factor, and constitutive HIF-2 activity restores tumorigenesis in VHL-reconstituted ccRCC cells. HIF-2 has been implicated in angiogenesis and multiple other processes, but angiogenesis is the main target of drugs such as the tyrosine kinase inhibitor sunitinib. HIF-2 has been regarded as undruggable. Here we use a tumourgraft/patient-derived xenograft platform to evaluate PT2399, a selective HIF-2 antagonist that was identified using a structure-based design approach. PT2399 dissociated HIF-2 (an obligatory heterodimer of HIF-2α-HIF-1β) in human ccRCC cells and suppressed tumorigenesis in 56% (10 out of 18) of such lines. PT2399 had greater activity than sunitinib, was active in sunitinib-progressing tumours, and was better tolerated. Unexpectedly, some VHL-mutant ccRCCs were resistant to PT2399. Resistance occurred despite HIF-2 dissociation in tumours and evidence of Hif-2 inhibition in the mouse, as determined by suppression of circulating erythropoietin, a HIF-2 target and possible pharmacodynamic marker. We identified a HIF-2-dependent gene signature in sensitive tumours. Gene expression was largely unaffected by PT2399 in resistant tumours, illustrating the specificity of the drug. Sensitive tumours exhibited a distinguishing gene expression signature and generally higher levels of HIF-2α. Prolonged PT2399 treatment led to resistance. We identified binding site and second site suppressor mutations in HIF-2α and HIF-1β, respectively. Both mutations preserved HIF-2 dimers despite treatment with PT2399. Finally, an extensively pretreated patient whose tumour had given rise to a sensitive tumourgraft showed disease control for more than 11 months when

Electrolytic treatment of colorectal liver tumour deposits in a rat model: a technique with potential for patients with unresectable liver tumours.

PubMed

Wemyss-Holden, S A; Robertson, G S; Hall, P D; Dennison, A R; Maddern, G J

2000-01-01

Patients with unresectable malignant liver tumours have a poor prognosis. A technique is needed which improves long-term survival. Previous studies in the rat have shown that electrolysis is a safe, predictable and reproducible method for creating areas of necrosis in the normal rat liver. This study examined the effects of electrolysis on colorectal liver 'metastases' in the rat. Tumours of colorectal origin were implanted into the livers of Wistar-WAG rats. Two weeks after implantation the tumours were treated with electrolysis. A direct current generator, connected to 2 platinum intrahepatic electrodes was used to examine the effects of various electrode configurations on the extent of tumour necrosis. Significant (p<0.001) tumour ablation was achieved with all electrode configurations. Tumour necrosis was more complete (p<0.05) with the electrodes positioned on either side of the tumour than with both electrodes placed in the centre of the tumour. Liver enzymes (AST and ALT) were significantly (p<0.001) elevated after treatment, but returned towards normal by 2 days. This study has shown that colorectal liver 'metastasis' can be ablated by electrolysis in a rat model. Two separate mechanisms of tumour ablation were observed: With the electrodes directly in or adjacent to the tumour, necrosis resulted from the action of cytotoxic electrode products, whereas by positioning the electrodes proximal to the tumour, necrosis was induced by a 'secondary' ischaemic effect. The findings confirm the view that electrolysis has great potential for treating patients with unresectable malignant liver tumours.

Tumours of the soft (mesenchymal) tissues

PubMed Central

Weiss, E.

1974-01-01

This is a classification of tumours of fibrous tissue, fat, muscle, blood and lymph vessels, and mast cells, irrespective of the region of the body in which they arise. Tumours of fibrous tissue are divided into fibroma, fibrosarcoma (including “canine haemangiopericytoma”), other sarcomas, equine sarcoid, and various tumour-like lesions. The histological appearance of the tumours is described and illustrated with photographs. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 9Fig. 10Fig. 11Fig. 12Fig. 17Fig. 18Fig. 19Fig. 20Fig. 5Fig. 6Fig. 7Fig. 8Fig. 13Fig. 14Fig. 15Fig. 16 PMID:4371740

The role of polyamine catabolism in anti-tumour drug response.

PubMed

Casero, R A; Wang, Y; Stewart, T M; Devereux, W; Hacker, A; Wang, Y; Smith, R; Woster, P M

2003-04-01

Interest in polyamine catabolism has increased since it has been directly associated with the cytotoxic response of multiple tumour types to exposure to specific anti-tumour polyamine analogues. Human polyamine catabolism was considered to be a two-step pathway regulated by the rate-limiting enzyme spermidine/spermine N(1)-acetyltransferase (SSAT) that provides substrate for an acetylpolyamine oxidase (APAO). Further, the super-induction of SSAT by several anti-tumour polyamine analogues has been implicated in the cytotoxic response of specific solid-tumour phenotypes to these agents. This high induction of SSAT has been correlated with cellular response to the anti-tumour polyamine analogues in several systems and considerable progress has been made in understanding the molecular mechanisms that regulate the analogue-induced expression of SSAT. A polyamine response element has been identified and the transacting transcription factors that bind and stimulate transcription of SSAT have been cloned and characterized. The link between SSAT activity and cellular toxicity is thought to be based on the production of H(2)O(2) by the activity of the constitutive APAO that uses the SSAT-produced acetylated polyamines. The high induction of SSAT and the subsequent activity of APAO are linked to the cytotoxic response of some tumour cell types to specific polyamine analogues. However, we have recently cloned a variably spliced human polyamine oxidase (PAOh1) that is inducible by specific polyamine analogues, efficiently uses unacetylated spermine as a substrate, and also produces toxic H(2)O(2) as a product. The results of studies with PAOh1 suggest that it is an additional enzyme in polyamine catabolism that has the potential to significantly contribute to polyamine homoeostasis and drug response. Most importantly, PAOh1 is induced by specific polyamine analogues in a tumour-phenotype-specific manner in cell lines representative of the major forms of solid tumours, including

Genomic analyses identify molecular subtypes of pancreatic cancer.

PubMed

Bailey, Peter; Chang, David K; Nones, Katia; Johns, Amber L; Patch, Ann-Marie; Gingras, Marie-Claude; Miller, David K; Christ, Angelika N; Bruxner, Tim J C; Quinn, Michael C; Nourse, Craig; Murtaugh, L Charles; Harliwong, Ivon; Idrisoglu, Senel; Manning, Suzanne; Nourbakhsh, Ehsan; Wani, Shivangi; Fink, Lynn; Holmes, Oliver; Chin, Venessa; Anderson, Matthew J; Kazakoff, Stephen; Leonard, Conrad; Newell, Felicity; Waddell, Nick; Wood, Scott; Xu, Qinying; Wilson, Peter J; Cloonan, Nicole; Kassahn, Karin S; Taylor, Darrin; Quek, Kelly; Robertson, Alan; Pantano, Lorena; Mincarelli, Laura; Sanchez, Luis N; Evers, Lisa; Wu, Jianmin; Pinese, Mark; Cowley, Mark J; Jones, Marc D; Colvin, Emily K; Nagrial, Adnan M; Humphrey, Emily S; Chantrill, Lorraine A; Mawson, Amanda; Humphris, Jeremy; Chou, Angela; Pajic, Marina; Scarlett, Christopher J; Pinho, Andreia V; Giry-Laterriere, Marc; Rooman, Ilse; Samra, Jaswinder S; Kench, James G; Lovell, Jessica A; Merrett, Neil D; Toon, Christopher W; Epari, Krishna; Nguyen, Nam Q; Barbour, Andrew; Zeps, Nikolajs; Moran-Jones, Kim; Jamieson, Nigel B; Graham, Janet S; Duthie, Fraser; Oien, Karin; Hair, Jane; Grützmann, Robert; Maitra, Anirban; Iacobuzio-Donahue, Christine A; Wolfgang, Christopher L; Morgan, Richard A; Lawlor, Rita T; Corbo, Vincenzo; Bassi, Claudio; Rusev, Borislav; Capelli, Paola; Salvia, Roberto; Tortora, Giampaolo; Mukhopadhyay, Debabrata; Petersen, Gloria M; Munzy, Donna M; Fisher, William E; Karim, Saadia A; Eshleman, James R; Hruban, Ralph H; Pilarsky, Christian; Morton, Jennifer P; Sansom, Owen J; Scarpa, Aldo; Musgrove, Elizabeth A; Bailey, Ulla-Maja Hagbo; Hofmann, Oliver; Sutherland, Robert L; Wheeler, David A; Gill, Anthony J; Gibbs, Richard A; Pearson, John V; Waddell, Nicola; Biankin, Andrew V; Grimmond, Sean M

2016-03-03

Integrated genomic analysis of 456 pancreatic ductal adenocarcinomas identified 32 recurrently mutated genes that aggregate into 10 pathways: KRAS, TGF-β, WNT, NOTCH, ROBO/SLIT signalling, G1/S transition, SWI-SNF, chromatin modification, DNA repair and RNA processing. Expression analysis defined 4 subtypes: (1) squamous; (2) pancreatic progenitor; (3) immunogenic; and (4) aberrantly differentiated endocrine exocrine (ADEX) that correlate with histopathological characteristics. Squamous tumours are enriched for TP53 and KDM6A mutations, upregulation of the TP63∆N transcriptional network, hypermethylation of pancreatic endodermal cell-fate determining genes and have a poor prognosis. Pancreatic progenitor tumours preferentially express genes involved in early pancreatic development (FOXA2/3, PDX1 and MNX1). ADEX tumours displayed upregulation of genes that regulate networks involved in KRAS activation, exocrine (NR5A2 and RBPJL), and endocrine differentiation (NEUROD1 and NKX2-2). Immunogenic tumours contained upregulated immune networks including pathways involved in acquired immune suppression. These data infer differences in the molecular evolution of pancreatic cancer subtypes and identify opportunities for therapeutic development.

Concomitant endometriosis in malignant and borderline ovarian tumours.

PubMed

Oral, Engin; Aydin, Ovgu; Kumbak, Banu Aygun; İlvan, Sennur; Yilmaz, Handan; Tustas, Esra; Bese, Tugan; Demirkiran, Fuat; Arvas, Macit

2018-06-08

The aim of the study was to reveal the prevalence of concomitant endometriosis in malignant and borderline ovarian tumours. A retrospective analysis was performed of 530 patients with malignant ovarian tumours and 131 with borderline ovarian tumours, who underwent surgery in our hospital between 1995 and 2011. Forty-eight (7.3%) of 661 patients with malignant and borderline ovarian tumours were associated with endometriosis. Of the 48 endometriosis cases, 73% of those were atypical. Infertility was noted in 38% of patients with endometriosis-associated ovarian tumours. The most frequently endometriosis-associated subtypes were endometrioid (33%) and clear cell (18%) histologies. Of endometriosis-associated endometrioid and clear cell ovarian tumours, 70% were early stage and 60% were premenopausal. The prevalence of concomitant endometriosis in borderline tumours (12%) was found to be significantly higher than that found in the malignant ones (6%; p = .02). Of 32 endometriosis-associated malignant ovarian tumours, 69% were FIGO stages I and II. In conclusion, ovarian endometriosis is seen with both malignant and borderline ovarian tumours, the association being significant with borderline tumours. Fortunately, the endometriosis-associated malignant ovarian tumours are mostly early stage. Impact statement What is already known on this subject? Epidemiologic data suggest that endometriosis has malignant potential. However, a subgroup of women with endometriosis at a high risk for ovarian cancer is yet to be clarified. Currently, endometriosis and ovarian cancer association does not seem to have a clinical implication. What do the results of this study add? The findings of this study revealed that nearly 75% of endometriosis-associated ovarian tumours were of atypical endometriosis. Half of endometriosis-associated ovarian tumour cases were of endometrioid/clear cell histology and 70% were early-stage. Endometriosis was significantly associated with borderline

Multiscale modelling and nonlinear simulation of vascular tumour growth

PubMed Central

Macklin, Paul; Anderson, Alexander R. A.; Chaplain, Mark A. J.; Cristini, Vittorio

2011-01-01

In this article, we present a new multiscale mathematical model for solid tumour growth which couples an improved model of tumour invasion with a model of tumour-induced angiogenesis. We perform nonlinear simulations of the multi-scale model that demonstrate the importance of the coupling between the development and remodeling of the vascular network, the blood flow through the network and the tumour progression. Consistent with clinical observations, the hydrostatic stress generated by tumour cell proliferation shuts down large portions of the vascular network dramatically affecting the flow, the subsequent network remodeling, the delivery of nutrients to the tumour and the subsequent tumour progression. In addition, extracellular matrix degradation by tumour cells is seen to have a dramatic affect on both the development of the vascular network and the growth response of the tumour. In particular, the newly developing vessels tend to encapsulate, rather than penetrate, the tumour and are thus less effective in delivering nutrients. PMID:18781303

The Clinical Significance of Occult Gastrointestinal Primary Tumours in Metastatic Cancer: A Population Retrospective Cohort Study.

PubMed

Hannouf, Malek B; Winquist, Eric; Mahmud, Salaheddin M; Brackstone, Muriel; Sarma, Sisira; Rodrigues, George; Rogan, Peter K; Hoch, Jeffrey S; Zaric, Gregory S

2018-01-01

The purpose of this study was to estimate the incidence of occult gastrointestinal (GI) primary tumours in patients with metastatic cancer of uncertain primary origin and evaluate their influence on treatments and overall survival (OS). We used population heath data from Manitoba, Canada to identify all patients initially diagnosed with metastatic cancer between 2002 and 2011. We defined patients to have "occult" primary tumour if the primary was found at least 6 months after initial diagnosis. Otherwise, we considered primary tumours as "obvious." We used propensity-score methods to match each patient with occult GI tumour to four patients with obvious GI tumour on all known clinicopathologic features. We compared treatments and 2-year survival data between the two patient groups and assessed treatment effect on OS using Cox regression adjustment. Eighty-three patients had occult GI primary tumours, accounting for 17.6% of men and 14% of women with metastatic cancer of uncertain primary. A 1:4 matching created a matched group of 332 patients with obvious GI primary tumour. Occult cases compared to the matched group were less likely to receive surgical interventions and targeted biological therapy, and more likely to receive cytotoxic empiric chemotherapeutic agents. Having an occult GI tumour was associated with reduced OS and appeared to be a nonsignificant independent predictor of OS when adjusting for treatment differences. GI tumours are the most common occult primary tumours in men and the second most common in women. Patients with occult GI primary tumours are potentially being undertreated with available GI site-specific and targeted therapies.

Optimising the combination dosing strategy of abemaciclib and vemurafenib in BRAF-mutated melanoma xenograft tumours

PubMed Central

Tate, Sonya C; Burke, Teresa F; Hartman, Daisy; Kulanthaivel, Palaniappan; Beckmann, Richard P; Cronier, Damien M

2016-01-01

Background: Resistance to BRAF inhibition is a major cause of treatment failure for BRAF-mutated metastatic melanoma patients. Abemaciclib, a cyclin-dependent kinase 4 and 6 inhibitor, overcomes this resistance in xenograft tumours and offers a promising drug combination. The present work aims to characterise the quantitative pharmacology of the abemaciclib/vemurafenib combination using a semimechanistic pharmacokinetic/pharmacodynamic modelling approach and to identify an optimum dosing regimen for potential clinical evaluation. Methods: A PK/biomarker model was developed to connect abemaciclib/vemurafenib concentrations to changes in MAPK and cell cycle pathway biomarkers in A375 BRAF-mutated melanoma xenografts. Resultant tumour growth inhibition was described by relating (i) MAPK pathway inhibition to apoptosis, (ii) mitotic cell density to tumour growth and, under resistant conditions, (iii) retinoblastoma protein inhibition to cell survival. Results: The model successfully described vemurafenib/abemaciclib-mediated changes in MAPK pathway and cell cycle biomarkers. Initial tumour shrinkage by vemurafenib, acquisition of resistance and subsequent abemaciclib-mediated efficacy were successfully captured and externally validated. Model simulations illustrate the benefit of intermittent vemurafenib therapy over continuous treatment, and indicate that continuous abemaciclib in combination with intermittent vemurafenib offers the potential for considerable tumour regression. Conclusions: The quantitative pharmacology of the abemaciclib/vemurafenib combination was successfully characterised and an optimised, clinically-relevant dosing strategy was identified. PMID:26978007

Tumour-induced osteomalacia: An emergent paraneoplastic syndrome.

PubMed

Alonso, Guillermo; Varsavsky, Mariela

2016-04-01

Endocrine paraneoplastic syndromes are distant manifestations of some tumours. An uncommon but increasingly reported form is tumour-induced osteomalacia, a hypophosphatemic disorder associated to fibroblast growth factor 23 (FGF-23) secretion by tumours. The main biochemical manifestations of this disorder include hypophosphatemia, inappropriately low or normal tubular reabsorption of phosphate, low serum calcitriol levels, increased serum alkaline phosphatase levels, and elevated or normal serum FGF-23 levels. These tumours, usually small, benign, slow growing and difficult to discover, are mainly localized in soft tissues of the limbs. Histologically, phosphaturic mesenchymal tumours of the mixed connective tissue type are most common. Various imaging techniques have been suggested with variable results. Treatment of choice is total surgical resection of the tumour. Medical treatment includes oral phosphorus and calcitriol supplements, octreotide, cinacalcet, and monoclonal antibodies. Copyright © 2015 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

Identification of genes involved in the biology of atypical teratoid/rhabdoid tumours using Drosophila melanogaster

NASA Astrophysics Data System (ADS)

Jeibmann, Astrid; Eikmeier, Kristin; Linge, Anna; Kool, Marcel; Koos, Björn; Schulz, Jacqueline; Albrecht, Stefanie; Bartelheim, Kerstin; Frühwald, Michael C.; Pfister, Stefan M.; Paulus, Werner; Hasselblatt, Martin

2014-06-01

Atypical teratoid/rhabdoid tumours (AT/RT) are malignant brain tumours. Unlike most other human brain tumours, AT/RT are characterized by inactivation of one single gene, SMARCB1. SMARCB1 is a member of the evolutionarily conserved SWI/SNF chromatin remodelling complex, which has an important role in the control of cell differentiation and proliferation. Little is known, however, about the pathways involved in the oncogenic effects of SMARCB1 inactivation, which might also represent targets for treatment. Here we report a comprehensive genetic screen in the fruit fly that revealed several genes not yet associated with loss of snr1, the Drosophila homologue of SMARCB1. We confirm the functional role of identified genes (including merlin, kibra and expanded, known to regulate hippo signalling pathway activity) in human rhabdoid tumour cell lines and AT/RT tumour samples. These results demonstrate that fly models can be employed for the identification of clinically relevant pathways in human cancer.

A novel pipeline for adrenal tumour segmentation.

PubMed

Koyuncu, Hasan; Ceylan, Rahime; Erdogan, Hasan; Sivri, Mesut

2018-06-01

Adrenal tumours occur on adrenal glands surrounded by organs and osteoid. These tumours can be categorized as either functional, non-functional, malign, or benign. Depending on their appearance in the abdomen, adrenal tumours can arise from one adrenal gland (unilateral) or from both adrenal glands (bilateral) and can connect with other organs, including the liver, spleen, pancreas, etc. This connection phenomenon constitutes the most important handicap against adrenal tumour segmentation. Size change, variety of shape, diverse location, and low contrast (similar grey values between the various tissues) are other disadvantages compounding segmentation difficulty. Few studies have considered adrenal tumour segmentation, and no significant improvement has been achieved for unilateral, bilateral, adherent, or noncohesive tumour segmentation. There is also no recognised segmentation pipeline or method for adrenal tumours including different shape, size, or location information. This study proposes an adrenal tumour segmentation (ATUS) pipeline designed to eliminate the above disadvantages for adrenal tumour segmentation. ATUS incorporates a number of image methods, including contrast limited adaptive histogram equalization, split and merge based on quadtree decomposition, mean shift segmentation, large grey level eliminator, and region growing. Performance assessment of ATUS was realised on 32 arterial and portal phase computed tomography images using six metrics: dice, jaccard, sensitivity, specificity, accuracy, and structural similarity index. ATUS achieved remarkable segmentation performance, and was not affected by the discussed handicaps, on particularly adherence to other organs, with success rates of 83.06%, 71.44%, 86.44%, 99.66%, 99.43%, and 98.51% for the metrics, respectively, for images including sufficient contrast uptake. The proposed ATUS system realises detailed adrenal tumour segmentation, and avoids known disadvantages preventing accurate

Transurethral resection and degeneration of bladder tumour

PubMed Central

Li, Aihua; Fang, Wei; Zhang, Feng; Li, Weiwu; Lu, Honghai; Liu, Sikuan; Wang, Hui; Zhang, Binghui

2013-01-01

Introduction: We evaluate the efficacy and safety of transurethral resection and degeneration of bladder tumour (TURD-Bt). Methods: In total, 56 patients with bladder tumour were treated by TURD-Bt. The results in these patients were compared with 32 patients treated by current transurethral resection of bladder tumour (TUR-Bt). Patients with or without disease progressive factors were respectively compared between the 2 groups. The factors included recurrent tumour, multiple tumours, tumour ≥3 cm in diameter, clinical stage T2, histological grade 3, adenocarcinoma, and ureteral obstruction or hydronephrosis. Results: Follow-up time was 48.55 ± 23.74 months in TURD-Bt group and 56.28 ± 17.61 months in the TUR-Bt group (p > 0.05). In patients without progressive factors, no tumour recurrence was found and overall survival was 14 (100%) in the TURD-Bt group; 3 (37.50%) patients had recurrence and overall survival was 5 (62.5%) in the TUR-Bt group. In patients with progressive factors, 8 (19.05%) patients had tumour recurrence, overall survival was 32 (76.19%) and cancer death was 3 (7.14%) in TURD-Bt group; 18 (75.00%) patients had tumour recurrence (p < 0.05), overall survival was 12 (50.00%) (p < 0.01) and cancer death was 8 (33.33%) (p < 0.05) in TUR-Bt group. No significant complication was found in TURD-Bt group. Conclusion: This study suggests that complete resection and degeneration of bladder tumour can be expected by TURD-Bt. The surgical procedure is safe and efficacious, and could be predictable and controllable before and during surgery. We would conclude that for bladder cancers without lymph node metastasis and distal metastasis, TURD-Bt could be performed to replace radical TUR-Bt and preserve the bladder. PMID:24475002

Overcoming resistance to molecularly targeted anticancer therapies: rational drug combinations based on EGFR and MAPK inhibition for solid tumours and haematologic malignancies

PubMed Central

Tortora, Giampaolo; Bianco, Roberto; Daniele, Gennaro; Ciardiello, Fortunato; McCubrey, James A; Ricciardi, Maria Rosaria; Ciuffreda, Ludovica; Cognetti, Francesco; Tafuri, Agostino; Milella, Michele

2007-01-01

Accumulating evidence suggests that cancer can be envisioned as a “signaling disease”, in which alterations in the cellular genome affect the expression and/or function of oncogenes and tumour suppressor genes. This ultimately disrupts the physiologic transmission of biochemical signals that normally regulate cell growth, differentiation and programmed cell death (apoptosis). From a clinical standpoint, signal transduction inhibition as a therapeutic strategy for human malignancies has recently achieved remarkable success. However, as additional drugs move forward into the clinical arena, intrinsic and acquired resistance to “targeted” agents becomes an issue for their clinical utility. One way to overcome resistance to targeted agents is to identify genetic and epigenetic aberrations underlying sensitivity/resistance, thus enabling the selection of patients that will most likely benefit from a specific therapy. Since resistance often ensues as a result of the concomitant activation of multiple, often overlapping, signaling pathways, another possibility is to interfere with multiple, cross-talking pathways involved in growth and survival control in a rational, mechanism-based, fashion. These concepts may be usefully applied, among others, to agents that target two major signal transduction pathways: the one initiated by epidermal growth factor receptor (EGFR) signaling and the one converging on mitogen-activated protein kinase (MAPK) activation. Here we review the molecular mechanisms of sensitivity/resistance to EGFR inhibitors, as well as the rationale for combining them with other targeted agents, in an attempt to overcome resistance. In the second part of the paper, we review MAPK-targeted agents, focusing on their therapeutic potential in hematologic malignancies, and examine the prospects for combinations of MAPK inhibitors with cytotoxic agents or other signal transduction-targeted agents to obtain synergistic anti-tumour effects. PMID:17482503

Multielement suppressor nozzles for thrust augmentation systems.

NASA Technical Reports Server (NTRS)

Lawrence, R. L.; O'Keefe, J. V.; Tate, R. B.

1972-01-01

The noise reduction and nozzle performance characteristics of large-scale, high-aspect-ratio multielement nozzle arrays operated at low velocities were determined by test. The nozzles are selected for application to high-aspect-ratio augmentor suppressors to be used for augmentor wing airplanes. Significant improvements in noise characteristics for multielement nozzles over those of round or high-aspect-ratio slot nozzles are obtained. Elliptical noise patterns typical of slot nozzles are presented for high-aspect-ratio multielement nozzle arrays. Additional advantages are available in OASPL noise reduction from the element size and spacing. Augmentor-suppressor systems can be designed for maximum beam pattern directivity and frequency spectrum shaping advantages. Measurements of the nozzle wakes show a correlation with noise level data and frequency spectrum peaks. The noise and jet wake results are compared with existing prediction procedures based on empirical jet flow equations, Lighthill relationships, Strouhal number, and empirical shock-induced screech noise effects.

In vivo electrical conductivity of hepatic tumours.

PubMed

Haemmerich, Dieter; Staelin, S T; Tsai, J Z; Tungjitkusolmun, S; Mahvi, D M; Webster, J G

2003-05-01

Knowledge of electrical tissue conductivity is necessary to determine deposition of electromagnetic energy and can further be used to diagnostically differentiate between normal and neoplastic tissue. We measured 17 rats with a total of 24 tumours of the K12/TRb rat colon cancer cell line. In each animal we measured in vivo hepatic tumour and normal tissue conductivity at seven frequencies from 10 Hz to 1 MHz, at different tumour stages between 6 and 12 weeks after induction. Conductivity of normal liver tissue was 1.26 +/- 0.15 mS cm(-1) at 10 Hz, and 4.61 +/- 0.42 mS cm(-1) at 1 MHz. Conductivity of tumour was 2.69 +/- 0.91 mS cm(-1) at 10 Hz, and 5.23 +/- 0.82 mS cm(-1) at 1 MHz. Conductivity was significantly different between normal and tumour tissue (p < 0.05). We determined the percentage of necrosis and fibrosis at the measurement site. We fitted the conductivity data to the Cole-Cole model. For the tumour data we determined Spearman's correlation coefficients between the Cole-Cole parameters and age, necrosis, fibrosis and tumour volume and found significant correlation between necrosis and the Cole-Cole parameters (p < 0.05). We conclude that necrosis within the tumour and the associated membrane breakdown is likely responsible for the observed change in conductivity.

Congenital portosystemic shunts associated with liver tumours.

PubMed

Pupulim, L F; Vullierme, M-P; Paradis, V; Valla, D; Terraz, S; Vilgrain, V

2013-07-01

To evaluate the diagnosis and presentation of liver tumours in patients with congenital portosystemic shunts (CPS). Eight patients were diagnosed in Hôpital Beaujon as having CPS. All patients underwent Doppler ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and histological examination of liver tumours. CPS were classified according to anatomy and the amount of portal flow deviated to the systemic circulation as: total, subtotal, or partial. Liver tumours were diagnosed by needle core biopsy (n = 5) or surgery (n = 3). Clinical follow-up was available in all patients but one (mean follow-up 36 months; range 1-5 years). Six patients had total CPS, one patient had a subtotal CPS, and the last had a partial CPS. All patients presented with multiple liver nodules (range four to >15). The tumours were characterized as focal nodular hyperplasia (FNH; n = 4), FNH with hepatocellular adenoma (n = 2), and regenerative nodular hyperplasia (n = 2). In four of seven patients (57%) that had follow-up, tumours showed enlargement or new lesions appeared. In this series of CPS patients, tumours were all benign, multiple, and of hepatocellular origin, and different tumours were present simultaneously in two patients. Tumour enlargement or new nodules were common during follow-up. Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

OPCML is a broad tumor suppressor for multiple carcinomas and lymphomas with frequently epigenetic inactivation.

PubMed

Cui, Yan; Ying, Ying; van Hasselt, Andrew; Ng, Ka Man; Yu, Jun; Zhang, Qian; Jin, Jie; Liu, Dingxie; Rhim, Johng S; Rha, Sun Young; Loyo, Myriam; Chan, Anthony T C; Srivastava, Gopesh; Tsao, George S W; Sellar, Grant C; Sung, Joseph J Y; Sidransky, David; Tao, Qian

2008-08-20

Identification of tumor suppressor genes (TSGs) silenced by CpG methylation uncovers the molecular mechanism of tumorigenesis and potential tumor biomarkers. Loss of heterozygosity at 11q25 is common in multiple tumors including nasopharyngeal carcinoma (NPC). OPCML, located at 11q25, is one of the downregulated genes we identified through digital expression subtraction. Semi-quantitative RT-PCR showed frequent OPCML silencing in NPC and other common tumors, with no homozygous deletion detected by multiplex differential DNA-PCR. Instead, promoter methylation of OPCML was frequently detected in multiple carcinoma cell lines (nasopharyngeal, esophageal, lung, gastric, colon, liver, breast, cervix, prostate), lymphoma cell lines (non-Hodgkin and Hodgkin lymphoma, nasal NK/T-cell lymphoma) and primary tumors, but not in any non-tumor cell line and seldom weakly methylated in normal epithelial tissues. Pharmacological and genetic demethylation restored OPCML expression, indicating a direct epigenetic silencing. We further found that OPCML is stress-responsive, but this response is epigenetically impaired when its promoter becomes methylated. Ecotopic expression of OPCML led to significant inhibition of both anchorage-dependent and -independent growth of carcinoma cells with endogenous silencing. Thus, through functional epigenetics, we identified OPCML as a broad tumor suppressor, which is frequently inactivated by methylation in multiple malignancies.

Canine transmissible venereal tumour: a review.

PubMed

Ganguly, B; Das, U; Das, A K

2016-03-01

Canine transmissible venereal tumour (CTVT) is a contagious venereal tumour of dogs, commonly observed in dogs that are in close contact with one another, or in stray and wild dogs that exhibit unrestrained sexual activity. CTVT represents a unique, naturally transmissible, contagious tumour, where the mutated tumour cell itself is the causative agent and perpetuates as a parasitic allograft in the host. Clinical history, signalment and cytological features are often obvious for establishing a diagnosis though biopsy and histological examination may be needed in atypical cases. Most cases are curable with three intravenous injections of vincristine sulphate at weekly intervals. The role of stray and wild dogs makes the disease difficult to control and necessitates sustained animal birth control in stray dogs along with prompt therapy of the affected dogs. This review captures the manifold developments in different areas embracing this fascinating tumour, including its biology, diagnosis and therapeutic alternatives. © 2013 John Wiley & Sons Ltd.

Extragonadal germ cell tumour with the "burned out" phenomenon mimicking a retroperitioneal tumour of neurogenic origin.

PubMed

González, Rocío; Montoto Santomé, Paula; Iglesias Porto, Eva; Pérez Moreiras, M Isabel; Salem Ali, Mohammed; Mateo Cambón, Luis A; Bal Nieves, Fernando; Arija Val, J Felix

2012-12-01

To describe a case of retroperitoneal metastasis of a gonadal germ cell tumour with the "burned-out" phenomenon in a 35 year old patient with a suspected diagnosis of retroperitoneal tumour of neurogenic origin. With the clinical and radiological suspicion of retroperitoneal tumour of neurogenic origin the tumour was removed, via the retroperitoneal space. Pathology showed classic seminoma with foci of atypical or anaplastic seminoma, confined to the tissue sample. After a genital examination showing no alterations, a scrotal ultrasound was requested. This revealed a badly delimited hypoechogenic mass with microcalcifications in the left testis and a heterogeneous echostructure in the right testis, with hypoechogenic areas and some microcalcification. Bilateral orchiectomy was performed, with a pathological study compatible with residual scar tissue in the left testicle and focal findings of germ cell neoplasia, with no intratubular seminoma in the right testis. The suspicion of an extragonadal germ cell tumour with the "burned-out" phenomenon modifies the therapeutic attitude, which should begin with orchiectomy, followed by systemic chemotherapy and the surgery kept in reserve for those cases where residual malignant tissue persists.

Phase congruency map driven brain tumour segmentation

NASA Astrophysics Data System (ADS)

Szilágyi, Tünde; Brady, Michael; Berényi, Ervin

2015-03-01

Computer Aided Diagnostic (CAD) systems are already of proven value in healthcare, especially for surgical planning, nevertheless much remains to be done. Gliomas are the most common brain tumours (70%) in adults, with a survival time of just 2-3 months if detected at WHO grades III or higher. Such tumours are extremely variable, necessitating multi-modal Magnetic Resonance Images (MRI). The use of Gadolinium-based contrast agents is only relevant at later stages of the disease where it highlights the enhancing rim of the tumour. Currently, there is no single accepted method that can be used as a reference. There are three main challenges with such images: to decide whether there is tumour present and is so localize it; to construct a mask that separates healthy and diseased tissue; and to differentiate between the tumour core and the surrounding oedema. This paper presents two contributions. First, we develop tumour seed selection based on multiscale multi-modal texture feature vectors. Second, we develop a method based on a local phase congruency based feature map to drive level-set segmentation. The segmentations achieved with our method are more accurate than previously presented methods, particularly for challenging low grade tumours.

Genomic evolution and chemoresistance in germ-cell tumours.

PubMed

Taylor-Weiner, Amaro; Zack, Travis; O'Donnell, Elizabeth; Guerriero, Jennifer L; Bernard, Brandon; Reddy, Anita; Han, G Celine; AlDubayan, Saud; Amin-Mansour, Ali; Schumacher, Steven E; Litchfield, Kevin; Turnbull, Clare; Gabriel, Stacey; Beroukhim, Rameen; Getz, Gad; Carter, Scott L; Hirsch, Michelle S; Letai, Anthony; Sweeney, Christopher; Van Allen, Eliezer M

2016-11-30

Germ-cell tumours (GCTs) are derived from germ cells and occur most frequently in the testes. GCTs are histologically heterogeneous and distinctly curable with chemotherapy. Gains of chromosome arm 12p and aneuploidy are nearly universal in GCTs, but specific somatic genomic features driving tumour initiation, chemosensitivity and progression are incompletely characterized. Here, using clinical whole-exome and transcriptome sequencing of precursor, primary (testicular and mediastinal) and chemoresistant metastatic human GCTs, we show that the primary somatic feature of GCTs is highly recurrent chromosome arm level amplifications and reciprocal deletions (reciprocal loss of heterozygosity), variations that are significantly enriched in GCTs compared to 19 other cancer types. These tumours also acquire KRAS mutations during the development from precursor to primary disease, and primary testicular GCTs (TGCTs) are uniformly wild type for TP53. In addition, by functional measurement of apoptotic signalling (BH3 profiling) of fresh tumour and adjacent tissue, we find that primary TGCTs have high mitochondrial priming that facilitates chemotherapy-induced apoptosis. Finally, by phylogenetic analysis of serial TGCTs that emerge with chemotherapy resistance, we show how TGCTs gain additional reciprocal loss of heterozygosity and that this is associated with loss of pluripotency markers (NANOG and POU5F1) in chemoresistant teratomas or transformed carcinomas. Our results demonstrate the distinct genomic features underlying the origins of this disease and associated with the chemosensitivity phenotype, as well as the rare progression to chemoresistance. These results identify the convergence of cancer genomics, mitochondrial priming and GCT evolution, and may provide insights into chemosensitivity and resistance in other cancers.

THE HISTONE DEACETYLASE SIRT6 IS A NOVEL TUMOR SUPPRESSOR THAT CONTROLS CANCER METABOLISM

PubMed Central

Sebastián, Carlos; Zwaans, Bernardette M. M.; Silberman, Dafne M.; Gymrek, Melissa; Goren, Alon; Zhong, Lei; Ram, Oren; Truelove, Jessica; Guimaraes, Alexander R.; Toiber, Debra; Cosentino, Claudia; Greenson, Joel K.; Mac Donald, Alasdair I; McGlynn, Liane; Maxwell, Fraser; Edwards, Joanne; Giacosa, Sofia; Guccione, Ernesto; Weissleder, Ralph; Bernstein, Bradley E.; Regev, Aviv; Shiels, Paul G.; Lombard, David B.; Mostoslavsky, Raul

2012-01-01

Reprogramming of cellular metabolism is a key event during tumorigenesis. Despite being known for decades (Warburg effect), the molecular mechanisms regulating this switch remained unexplored. Here, we identify SIRT6 as a novel tumor suppressor that regulates aerobic glycolysis in cancer cells. Importantly, loss of SIRT6 leads to tumor formation without activation of known oncogenes, while transformed SIRT6-deficient cells display increased glycolysis and tumor growth, suggesting that SIRT6 plays a role in both establishment and maintenance of cancer. Using a conditional SIRT6 allele, we show that SIRT6 deletion in vivo increases the number, size and aggressiveness of tumors. SIRT6 also functions as a novel regulator of ribosome metabolism by co-repressing MYC transcriptional activity. Lastly, SIRT6 is selectively downregulated in several human cancers, and expression levels of SIRT6 predict prognosis and tumor-free survival rates, highlighting SIRT6 as a critical modulator of cancer metabolism. Our studies reveal SIRT6 to be a potent tumor suppressor acting to suppress cancer metabolism. PMID:23217706

Tumours can act as adjuvants for humoral immunity

PubMed Central

Brown, D M; Fisher, T L; Wei, C; Frelinger, J G; Lord, E M

2001-01-01

Tumour cells transfected with cDNAs encoding non-self proteins were used to investigate the ability of the immune system to respond to immunogenic antigens expressed by tumours. Secreted, intracellular and surface proteins were used as model antigens, as these reflect the potential forms of tumour antigens. Syngeneic BALB/c mice injected with viable line 1 lung carcinoma or EMT6 mammary tumour cells secreting ovalbumin (OVA) or prostate-specific antigen (PSA) produced very high immunoglobulin G (IgG) antibody titres, equivalent to those of mice injected with protein in Freund's complete adjuvant (FCA). Secretion of the antigens was not necessary as tumour cells expressing a cell-surface antigen (HER-2/Neu) or an intracellular antigen – green fluorescence protein (GFP) – also generated high-titre antigen-specific IgG antibodies. In interleukin-4 (IL-4)-deficient mice, both IgG1 and IgG2a were produced in response to OVA administered in FCA, whereas in response to tumour-produced antigen, the antibodies switched from predominantly IgG1 to IgG2a, indicating that the mechanisms responsible for antibody induction differed between these forms of immunization. In contrast to the line 1 and EMT6 tumours, which are of BALB/c origin, OVA- or PSA-producing B16 melanoma cells, which are of C57BL/6 origin, failed to elicit antibody production. This was not the result of strain differences, as a similar finding was observed when the tumours were grown in (BALB/c × C57BL/6)F1 mice, but appeared to be caused by intrinsic differences in the tumours. Furthermore, co-injection of both B16/OVA and line 1 tumours resulted in production of anti-OVA antibody, indicating that B16 tumours were not immunosuppressive, but instead line 1 tumours appear to exert an adjuvant effect. PMID:11328383

Review article: the investigation and management of gastric neuroendocrine tumours.

PubMed

Basuroy, R; Srirajaskanthan, R; Prachalias, A; Quaglia, A; Ramage, J K

2014-05-01

Gastric carcinoids (GCs) or neuroendocrine tumours (NETs) are increasingly identified at endoscopy, and account for 0.6-2% of all gastric polyps identified. The SEER database in the US has demonstrated a rising incidence of gastric NETs amongst all NETs; from 2.2% between 1950 and 1969 to 6.0% between 2000 and 2007. To review the literature and assist clinicians in managing patients with GCs. A literature search was conducted through MEDLINE using search terms: gastric, carcinoid, neuroendocrine tumour, therapy, endoscopy, mucosal resection, submucosal dissection. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles. There are three types of GCs with important epidemiological, pathophysiological, histological and endoscopic differences that affect prognosis and management. Type 1 and 2 GCs develop in the context of hypergastrinaemia that originates from achlorhydria in atrophic gastritis and a gastrinoma, respectively. Type 3 GCs occur sporadically and independent of gastrin. The histological type, grade and Ki67 index are used to determine prognosis and direct clinical management. Type 1 GCs >1 cm in size and type 2 GCs should be assessed for invasion beyond the submucosa with EUS prior to endoscopic resection with EMR or ESD. Type 3 GCs should be managed as per recommendations for gastric adenocarcinoma. The treatment of advanced disease is multimodal. Patients with gastric carcinoids should be discussed in a specialist neuroendocrine tumour multidisciplinary meeting to ensure all treatment options are explored in localised and advanced disease. Areas of controversy exist that need further research. © 2014 John Wiley & Sons Ltd.

Chemical suppressors of mlo-mediated powdery mildew resistance

PubMed Central

Wu, Hongpo; Kwaaitaal, Mark; Strugala, Roxana; Schaffrath, Ulrich; Bednarek, Paweł

2017-01-01

Loss-of-function of barley mildew locus o (Mlo) confers durable broad-spectrum penetration resistance to the barley powdery mildew pathogen, Blumeria graminis f. sp. hordei (Bgh). Given the importance of mlo mutants in agriculture, surprisingly few molecular components have been identified to be required for this type of resistance in barley. With the aim to identify novel cellular factors contributing to mlo-based resistance, we devised a pharmacological inhibitor screen. Of the 41 rationally chosen compounds tested, five caused a partial suppression of mlo resistance in barley, indicated by increased levels of Bgh host cell entry. These chemicals comprise brefeldin A (BFA), 2′,3′-dideoxyadenosine (DDA), 2-deoxy-d-glucose, spermidine, and 1-aminobenzotriazole. Further inhibitor analysis corroborated a key role for both anterograde and retrograde endomembrane trafficking in mlo resistance. In addition, all four ribonucleosides, some ribonucleoside derivatives, two of the five nucleobases (guanine and uracil), some guanine derivatives as well as various polyamines partially suppress mlo resistance in barley via yet unknown mechanisms. Most of the chemicals identified to be effective in partially relieving mlo resistance in barley also to some extent compromised powdery mildew resistance in an Arabidopsis mlo2 mlo6 double mutant. In summary, our study identified novel suppressors of mlo resistance that may serve as valuable probes to unravel further the molecular processes underlying this unusual type of disease resistance. PMID:29127104

The Heterologous Expression of the p22 RNA Silencing Suppressor of the Crinivirus Tomato Chlorosis Virus from Tobacco Rattle Virus and Potato Virus X Enhances Disease Severity but Does Not Complement Suppressor-Defective Mutant Viruses.

PubMed

Landeo-Ríos, Yazmín; Navas-Castillo, Jesús; Moriones, Enrique; Cañizares, M. Carmen

2017-11-24

To counteract host antiviral RNA silencing, plant viruses express suppressor proteins that function as pathogenicity enhancers. The genome of the Tomato chlorosis virus (ToCV) (genus Crinivirus , family Closteroviridae ) encodes an RNA silencing suppressor, the protein p22, that has been described as having one of the longest lasting local suppressor activities when assayed in Nicotiana benthamiana . Since suppression of RNA silencing and the ability to enhance disease severity are closely associated, we analyzed the effect of expressing p22 in heterologous viral contexts. Thus, we studied the effect of the expression of ToCV p22 from viral vectors Tobacco rattle virus (TRV) and Potato virus X (PVX), and from attenuated suppressor mutants in N. benthamiana plants. Our results show that although an exacerbation of disease symptoms leading to plant death was observed in the heterologous expression of ToCV p22 from both viruses, only in the case of TRV did increased viral accumulation occur. The heterologous expression of ToCV p22 could not complement suppressor-defective mutant viruses.

Tumours of the nasal cavity*

PubMed Central

Stünzi, H.; Hauser, B.

1976-01-01

Tumours of the nasal cavity are rare in domestic animals, most cases occurring in the dog. Epithelial tumours are the most common type in carnivores (dogs and cats). In general, the same types of tumour occur in domestic animals as occur in man. There was no significant predisposition for breed in dogs, but in both dogs and cats far more males than females were affected. Metastases occurred only rarely. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 9Fig. 10Fig. 11Fig. 12Fig. 5Fig. 6Fig. 7Fig. 8 PMID:1086156

Challenges in surgical pathology of adrenocortical tumours.

PubMed

Erickson, Lori A

2018-01-01

Adrenocortical carcinomas are rare tumours that can be diagnostically challenging. Numerous multiparametric scoring systems and diagnostic algorithms have been proposed to differentiate adrenocortical adenoma from adrenocortical carcinoma. Adrenocortical neoplasms must also be differentiated from other primary adrenal tumours, such as phaeochromocytoma and unusual primary adrenal tumours, as well as metastases to the adrenal gland. Myxoid, oncocytic and sarcomatoid variants of adrenocortical tumours must be recognized so that they are not confused with other tumours. The diagnostic criteria for oncocytic adrenocortical carcinoma are different from those for conventional adrenocortical carcinomas. Adrenocortical neoplasms in children are particularly challenging to diagnose, as histological features of malignancy in adrenocortical neoplasms in adults may not be associated with aggressive disease in the tumours of children. Recent histological and immunohistochemical studies and more comprehensive and integrated genomic characterizations continue to advance our understanding of the tumorigenesis of these aggressive neoplasms, and may provide additional diagnostic and prognostic utility and guide the development of therapeutic targets. © 2017 John Wiley & Sons Ltd.

Fertility sparing treatment in borderline ovarian tumours

PubMed Central

Alvarez, Rosa Maria; Vazquez-Vicente, Daniel

2015-01-01

Borderline ovarian tumours are low malignant potential tumours. They represent 10–15% of all epithelial ovarian malignancies. Patients with this type of tumour are younger at the time of diagnosis than patients with invasive ovarian cancer. Most of them are diagnosed in the early stages and have an excellent prognosis. It has been quite clearly established that the majority of borderline ovarian tumours should be managed with surgery alone. Because a high proportion of women with this malignancy are young and the prognosis is excellent, the preservation of fertility is an important issue in the management of these tumours. In this systemic review of the literature, we have evaluated in-depth oncological safety and reproductive outcomes in women with borderline ovarian tumours treated with fertility-sparing surgery, reviewing the indications, benefits, and disadvantages of each type of conservative surgery, as well as new alternative options to surgery to preserve fertility. PMID:25729420

Peptidomic analysis of endogenous plasma peptides from patients with pancreatic neuroendocrine tumours.

PubMed

Kay, Richard G; Challis, Benjamin G; Casey, Ruth T; Roberts, Geoffrey P; Meek, Claire L; Reimann, Frank; Gribble, Fiona M

2018-06-01

Diagnosis of pancreatic neuroendocrine tumours requires the study of patient plasma with multiple immunoassays, using multiple aliquots of plasma. The application of mass spectrometry based techniques could reduce the cost and amount of plasma required for diagnosis. Plasma samples from two patients with pancreatic neuroendocrine tumours were extracted using an established acetonitrile based plasma peptide enrichment strategy. The circulating peptidome was characterised using nano and high flow rate LC/MS analyses. To assess the diagnostic potential of the analytical approach, a large sample batch (68 plasmas) from control subjects, and aliquots from subjects harbouring two different types of pancreatic neuroendocrine tumour (insulinoma and glucagonoma) were analysed using a 10-minute LC/MS peptide screen. The untargeted plasma peptidomics approach identified peptides derived from the glucagon prohormone, chromogranin A, chromogranin B and other peptide hormones and proteins related to control of peptide secretion. The glucagon prohormone derived peptides that were detected were compared against putative peptides that were identified using multiple antibody pairs against glucagon peptides. Comparison of the plasma samples for relative levels of selected peptides showed clear separation between the glucagonoma and the insulinoma and control samples. The combination of the organic solvent extraction methodology with high flow rate analysis could potentially be used to aid diagnosis and monitor treatment of patients with functioning pancreatic neuroendocrine tumours. However, significant validation will be required before this approach can be clinically applied. This article is protected by copyright. All rights reserved.

A chemotactic signaling surface on CheY defined by suppressors of flagellar switch mutations.

PubMed Central

Roman, S J; Meyers, M; Volz, K; Matsumura, P

1992-01-01

CheY is the response regulator protein that interacts with the flagellar switch apparatus to modulate flagellar rotation during chemotactic signaling. CheY can be phosphorylated and dephosphorylated in vitro, and evidence indicates that CheY-P is the activated form that induces clockwise flagellar rotation, resulting in a tumble in the cell's swimming pattern. The flagellar switch apparatus is a complex macromolecular structure composed of at least three gene products, FliG, FliM, and FliN. Genetic analysis of Escherichia coli has identified fliG and fliM as genes in which mutations occur that allele specifically suppress cheY mutations, indicating interactions among these gene products. We have generated a class of cheY mutations selected for dominant suppression of fliG mutations. Interestingly, these cheY mutations dominantly suppressed both fliG and fliM mutations; this is consistent with the idea that the CheY protein interacts with both switch gene products during signaling. Biochemical characterization of wild-type and suppressor CheY proteins did not reveal altered phosphorylation properties or evidence for phosphorylation-dependent CheY multimerization. These data indicate that suppressor CheY proteins are specifically altered in the ability to transduce chemotactic signals to the switch at some point subsequent to phosphorylation. Physical mapping of suppressor amino acid substitutions on the crystal structure of CheY revealed a high degree of spatial clustering, suggesting that this region of CheY is a signaling surface that transduces chemotactic signals to the switch. Images PMID:1400175

Downregulation of TLX induces TET3 expression and inhibits glioblastoma stem cell self-renewal and tumorigenesis.

PubMed

Cui, Qi; Yang, Su; Ye, Peng; Tian, E; Sun, Guoqiang; Zhou, Jiehua; Sun, Guihua; Liu, Xiaoxuan; Chen, Chao; Murai, Kiyohito; Zhao, Chunnian; Azizian, Krist T; Yang, Lu; Warden, Charles; Wu, Xiwei; D'Apuzzo, Massimo; Brown, Christine; Badie, Behnam; Peng, Ling; Riggs, Arthur D; Rossi, John J; Shi, Yanhong

2016-02-03

Glioblastomas have been proposed to be maintained by highly tumorigenic glioblastoma stem cells (GSCs) that are resistant to current therapy. Therefore, targeting GSCs is critical for developing effective therapies for glioblastoma. In this study, we identify the regulatory cascade of the nuclear receptor TLX and the DNA hydroxylase Ten eleven translocation 3 (TET3) as a target for human GSCs. We show that knockdown of TLX expression inhibits human GSC tumorigenicity in mice. Treatment of human GSC-grafted mice with viral vector-delivered TLX shRNA or nanovector-delivered TLX siRNA inhibits tumour development and prolongs survival. Moreover, we identify TET3 as a potent tumour suppressor downstream of TLX to regulate the growth and self-renewal in GSCs. This study identifies the TLX-TET3 axis as a potential therapeutic target for glioblastoma.

Soft Tissue Tumours of the Retroperitoneum

PubMed Central

Van Roggen, J. Frans Graadt

2000-01-01

Purpose. This review summarizes the more prevalent soft tissue tumours arising in the retroperitoneum and highlights some recent fundamental and diagnostic developments relevant to mesenchymal tumours. Discussion. The retroperitoneum is an underestimated site for benign and malignant neoplastic disease, and represents the second most common site of origin of primary malignant soft tissue tumours (sarcomas) after the deep tissues of the lower extremity. In contrast to the predominance of benign soft tissue lesions over malignant sarcomas elsewhere, retroperitoneal mesenchymal lesions are far more likely to be malignant. The differential diagnosis is primarily with the more common lymphoproliferative and parenchymatous epithelial lesions arising in this area, and with metastatic disease from known or unknown primary sites elsewhere.The most prevalent mesenchymal tumours at this site are of a lipomatous, myogenic or neural nature.Their generally late clinical presentation and poorly accessible location provides numerous clinical challenges; optimal radiological imaging and a properly performed biopsy are essential cogs in the management route. Histopathological diagnosis may be complicated, but has been aided by developments in the fields of immunohistochemistry and tumour (cyto)genetics. Despite significant advances in oncological management protocols, the prognosis remains generally less favourable than for similar tumours at more accessible sites. PMID:18521430

Myeloid-derived suppressor cells

PubMed Central

Chandra, Dinesh; Gravekamp, Claudia

2013-01-01

While conventional anticancer therapies, including surgical resection, radiotherapy, and/or chemotherapy, are relatively efficient at eliminating primary tumors, these treatment modalities are largely ineffective against metastases. At least in part, this reflects the rather inefficient delivery of conventional anticancer agents to metastatic lesions. We have recently demonstrated that myeloid-derived suppressor cells (MDSCs) can be used as cellular missiles to selectively deliver a radioisotope-coupled attenuated variant of Listeria monocytogenes to both primary and metastatic neoplastic lesions in mice with pancreatic cancer. This novel immunotherapeutic intervention robustly inhibited tumor growth while promoting a dramatic decrease in the number of metastases. PMID:24427545

Mechanisms of the HRSL3 tumor suppressor function in ovarian carcinoma cells.

PubMed

Nazarenko, Irina; Schäfer, Reinhold; Sers, Christine

2007-04-15

HRSL3 (also known as H-REV107-1) belongs to a class II tumor suppressor gene family and is downregulated in several human tumors including ovarian carcinomas. To unravel the mechanism of HRSL3 tumor suppressor action, we performed a yeast two-hybrid screen and identified the alpha-isoform of the regulatory subunit A of protein phosphatase 2A (PR65alpha) as a new interaction partner of HRSL3. Interaction between HRSL3 and PR65alpha was confirmed in vitro and by co-immunoprecipitation in mammalian cells. We demonstrate that HRSL3 binds to the endogenous PR65alpha, thereby partially sequestering the catalytic subunit PR36 from the PR65 protein complex, and inhibiting PP2A catalytic activity. Furthermore, binding of HRSL3 to PR65 induces apoptosis in ovarian carcinoma cells in a caspase-dependent manner. Using several mutant HRSL3 constructs, we identified the N-terminal proline-rich region within the HRSL3 protein as the domain that is relevant for both binding of PR65alpha and induction of programmed cell death. This suggests that the negative impact of HRSL3 onto PP2A activity is important for the HRSL3 pro-apoptotic function and indicates a role of PP2A in survival of human ovarian carcinomas. The analysis of distinct PP2A target molecules revealed PKCzeta as being involved in HRSL3 action. These data implicate HRSL3 as a signaling regulatory molecule, which is functionally involved in the oncogenic network mediating growth and survival of ovarian cancer cells.

Multicellular Streaming in Solid Tumours

NASA Astrophysics Data System (ADS)

Kas, Josef

As early as 400 BCE, the Roman medical encyclopaedist Celsus recognized that solid tumours are stiffer than surrounding tissue. However, cancer cell lines are softer, and softer cells facilitate invasion. This paradox raises several questions: Does softness emerge from adaptation to mechanical and chemical cues in the external microenvironment, or are soft cells already present inside a primary solid tumour? If the latter, how can a more rigid tissue contain more soft cells? Here we show that in primary tumour samples from patients with mammary and cervix carcinomas, cells do exhibit a broad distribution of rigidities, with a higher fraction of softer and more contractile cells compared to normal tissue. Mechanical modelling based on patient data reveals that, surprisingly, tumours with a significant fraction of very soft cells can still remain rigid. Moreover, in tissues with the observed distributions of cell stiffnesses, softer cells spontaneously self-organize into lines or streams, possibly facilitating cancer metastasis.

A viral suppressor of RNA silencing inhibits ARGONAUTE 1 function by precluding target RNA binding to pre-assembled RISC

PubMed Central

Kenesi, Erzsébet; Lózsa, Rita

2017-01-01

Abstract In most eukaryotes, RNA silencing is an adaptive immune system regulating key biological processes including antiviral defense. To evade this response, viruses of plants, worms and insects have evolved viral suppressors of RNA silencing proteins (VSRs). Various VSRs, such as P1 from Sweet potato mild mottle virus (SPMMV), inhibit the activity of RNA-induced silencing complexes (RISCs) including an ARGONAUTE (AGO) protein loaded with a small RNA. However, the specific mechanisms explaining this class of inhibition are unknown. Here, we show that SPMMV P1 interacts with AGO1 and AGO2 from Arabidopsis thaliana, but solely interferes with AGO1 function. Moreover, a mutational analysis of a newly identified zinc finger domain in P1 revealed that this domain could represent an effector domain as it is required for P1 suppressor activity but not for AGO1 binding. Finally, a comparative analysis of the target RNA binding capacity of AGO1 in the presence of wild-type or suppressor-defective P1 forms revealed that P1 blocks target RNA binding to AGO1. Our results describe the negative regulation of RISC, the small RNA containing molecular machine. PMID:28499009

Anti-tumour therapeutic efficacy of OX40L in murine tumour model.

PubMed

Ali, Selman A; Ahmad, Murrium; Lynam, June; McLean, Cornelia S; Entwisle, Claire; Loudon, Peter; Choolun, Esther; McArdle, Stephanie E B; Li, Geng; Mian, Shahid; Rees, Robert C

2004-09-09

OX40 ligand (OX40L), a member of TNF superfamily, is a co-stimulatory molecule involved in T cell activation. Systemic administration of mOX40L fusion protein significantly inhibited the growth of experimental lung metastasis and subcutaneous (s.c.) established colon (CT26) and breast (4T1) carcinomas. Vaccination with OX40L was significantly enhanced by combination treatment with intra-tumour injection of a disabled infectious single cycle-herpes simplex virus (DISC-HSV) vector encoding murine granulocyte macrophage-colony stimulating factor (mGM-CSF). Tumour rejection in response to OX40L therapy required functional CD4+ and CD8+ T cells and correlated with splenocyte cytotoxic T lymphocytes (CTLs) activity against the AH-1 gp70 peptide of the tumour associated antigen expressed by CT26 cells. These results demonstrate the potential role of the OX40L in cancer immunotherapy.

Suppressor Mutations for Presenilin 1 Familial Alzheimer Disease Mutants Modulate γ-Secretase Activities.

PubMed

Futai, Eugene; Osawa, Satoko; Cai, Tetsuo; Fujisawa, Tomoya; Ishiura, Shoichi; Tomita, Taisuke

2016-01-01

γ-Secretase is a multisubunit membrane protein complex containing presenilin (PS1) as a catalytic subunit. Familial Alzheimer disease (FAD) mutations within PS1 were analyzed in yeast cells artificially expressing membrane-bound substrate, amyloid precursor protein, or Notch fused to Gal4 transcriptional activator. The FAD mutations, L166P and G384A (Leu-166 to Pro and Gly-384 to Ala substitution, respectively), were loss-of-function in yeast. We identified five amino acid substitutions that suppress the FAD mutations. The cleavage of amyloid precursor protein or Notch was recovered by the secondary mutations. We also found that secondary mutations alone activated the γ-secretase activity. FAD mutants with suppressor mutations, L432M or S438P within TMD9 together with a missense mutation in the second or sixth loops, regained γ-secretase activity when introduced into presenilin null mouse fibroblasts. Notably, the cells with suppressor mutants produced a decreased amount of Aβ42, which is responsible for Alzheimer disease. These results indicate that the yeast system is useful to screen for mutations and chemicals that modulate γ-secretase activity. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Suppressor Effects of Positive and Negative Religious Coping on Academic Burnout Among Korean Middle School Students.

PubMed

Noh, Hyunkyung; Chang, Eunbi; Jang, Yoojin; Lee, Ji Hae; Lee, Sang Min

2016-02-01

Statistical suppressor effects in prediction models can provide evidence of the interdependent relationship of independent variables. In this study, the suppressor effects of positive and negative religious coping on academic burnout were examined using longitudinal data. First, 388 middle school students reported their type of religion and use of positive and negative religious coping strategies. Four months later, they also reported their level of academic burnout. From structural equation modeling, significant suppressor effects were found among religious students. That is, the coefficients became larger when both positive and negative religious coping predicted academic burnout simultaneously, compared to when each religious coping predicted academic burnout alone. However, suppressor effects were not found among non-religious students.

Granular Media-Based Tunable Passive Vibration Suppressor

NASA Technical Reports Server (NTRS)

Dillon, Robert P.; Davis, Gregory L.; Shapiro, Andrew A.; Borgonia, John Paul C.; Kahn, Daniel L.; Boechler, Nicholas; Boechler,, Chiara

2013-01-01

isolation (Figure 1). This configuration is referred to as a single-axis vibration suppressor. This invention also includes further designs for the integration of the single-axis vibration suppressor into a six-degree-of-freedom hexapod "Stewart"mounting configuration (Figure 2). By integrating each singleaxis vibration suppressor into a hexapod formation, a payload will be protected in all six degrees of freedom from shock and/or vibration. Additionally, to further enable the application of this device to multiple operational scenarios, particularly in the case of high loads, the vibration suppressor devices can be used in parallel in any array configuration.

Breast carcinoma metastasis suppressor gene 1 (BRMS1): update on its role as the suppressor of cancer metastases.

PubMed

Kodura, Magdalena Anna; Souchelnytskyi, Serhiy

2015-12-01

BRMS1 was discovered over a decade ago as a potential tumor suppressor gene. In this review, we summarize the recent findings about the structure of BRMS1, mechanisms of its action and a role of BRMS1 in the cancer progression. As a suppressor of metastasis, BRMS1 has demonstrated a variety of ways to act on the cell functions, such as cell migration, invasiveness, angiogenesis, cell survival, cytoskeleton rearrangements, cell adhesion, and immune recognition. This variety of effects is a likely reason behind the robustness of anti-metastatic influence of BRMS1. Intracellular signaling mechanisms employed by BRMS1 include regulation of transcription, EGF/HER2 signaling, and expression of NF-kB, fascin, osteopontin, and IL-6. Recently reported clinical studies confirm that BRMS1 can indeed be used as a prognostic marker. Approaches to employ BRMS1 in a development of anti-cancer treatment have also been made. The studies reviewed here with respect to BRMS1 structure, cellular effects, intracellular signaling, and clinical value consolidate the importance of BRMS1 in the development of metastasis.

Continuation of surge life of transient voltage suppressor

NASA Technical Reports Server (NTRS)

Clark, O. M.

1977-01-01

Efforts expended in testing, analyzing and the development of a meaningful definition of the mean number of peak pulses before failure (mp2bf) levels of a family of transient voltage suppressor devices were documented. Tests were done to determine the ability of the transient suppressor to effectively and reliably protect against severe short term, millisecond range, and transient voltages of the types resulting from inductive load switching and induced lightning. Existing pulse testing instrumentation was utilized, interfaced to an automatic sequencing test rack accommodating up to 50 devices. Tests were performed in step stress increments of 25% beginning at 25% and extending thru 100% rated I(pp) for each voltage category. The four voltage types test were the 6.8V, 33V, 91V, and 190V. Engineering efforts addressed the problem of improving the reliability of the 190V types.

T cell chronic lymphocytic leukaemia with suppressor phenotype.

PubMed Central

Hofman, F M; Smith, D; Hocking, W

1982-01-01

The peripheral blood cells from a patient with T cell chronic lymphocytic leukaemia were examined for surface marker and functional characteristics. Eighty-91% of the peripheral blood cells formed SRBC rosettes and 22-49% possessed Fc receptors; 73% of the peripheral blood cells were reactive with the OKT8 antiserum and 61% expressed DR antigens. Response to PHA stimulation was markedly reduced, whereas allogeneic responsiveness in mixed leucocyte culture was intact. The ability of Con A-stimulated peripheral blood cells to generate suppressor activity in a mixed leucocyte reaction was deficient, whereas suppression of in vitro immunoglobulin synthesis was greater than normal. The leukaemic peripheral blood cell population expressed a T suppressor phenotype. Functional studies suggest that these cells were derived from the subset of T lymphocytes with regulatory activity for immunoglobulin synthesis as opposed to mitogenic responsiveness. PMID:6215199

SST Technology Follow-On Program - Phase 2. Noise Suppressor/Nozzle Development. Volume 9. Performance Technology - Analysis of the Low Speed Performance of Multitube Suppressor/Ejector Nozzles (0-167 kn)

DTIC Science & Technology

1975-03-01

Layer Suction 18 Temperature and Pressure Profile at Charging Station |9 Roiind-Corivergent Reference Nozzle 20 Elliptical Ramps 21 37-Tube...between plumes of the jets in the outer row of a suppressor Homulary layer Discharge coelticient, accounting for temperature induced no/./Ie area...tunnel floor. The suppressor air tlow rate was measured with an A.S.M.H. long-radius flow nozzle. The boundary layer ihickness at the ejector inlet

Systemic Effects of Non-Endocrine Tumours

PubMed Central

Sullivan, James D.; Rona, George

1964-01-01

Tumours of non-endocrine origin may exert deleterious effects by elaborating active principles which disturb body regulation. Systemic manifestations are fairly common with neoplasms of the lung, kidney, gastro-intestinal tract and thymus. The secretion of these tumours may have a known chemical structure (serotonin), may present hormone-like action (parathormone, antidiuretic hormone, insulinoid), or have well-defined biological properties (erythropoietin, gastrin-like principle). Tumours may stimulate endocrine glands by an unknown mechanism, producing disorders such as Cushing's syndrome, hypercalcemia, gynecomastia and hypoglycemia. Thymomas may be associated with autoimmune diseases. Tumours may extensively utilize or excrete some metabolite (glucose) or electrolyte (Na or K). Awareness of the systemic effects of various neoplasms may lead to an early diagnosis and proper treatment of these manifestations. PMID:14204555

Molecular chaperone Hsp27 regulates the Hippo tumor suppressor pathway in cancer.

PubMed

Vahid, Sepideh; Thaper, Daksh; Gibson, Kate F; Bishop, Jennifer L; Zoubeidi, Amina

2016-08-24

Heat shock protein 27 (Hsp27) is a molecular chaperone highly expressed in aggressive cancers, where it is involved in numerous pro-tumorigenic signaling pathways. Using functional genomics we identified for the first time that Hsp27 regulates the gene signature of transcriptional co-activators YAP and TAZ, which are negatively regulated by the Hippo Tumor Suppressor pathway. The Hippo pathway inactivates YAP by phosphorylating and increasing its cytoplasmic retention with the 14.3.3 proteins. Gain and loss of function experiments in prostate, breast and lung cancer cells showed that Hsp27 knockdown induced YAP phosphorylation and cytoplasmic localization while overexpression of Hsp27 displayed opposite results. Mechanistically, Hsp27 regulates the Hippo pathway by accelerating the proteasomal degradation of ubiquitinated MST1, the core Hippo kinase, resulting in reduced phosphorylation/activity of LATS1 and MOB1, its downstream effectors. Importantly, our in vitro results were supported by data from human tumors; clinically, high expression of Hsp27 in prostate tumors is correlated with increased expression of YAP gene signature and reduced phosphorylation of YAP in lung and invasive breast cancer clinical samples. This study reveals for the first time a link between Hsp27 and the Hippo cascade, providing a novel mechanism of deregulation of this tumor suppressor pathway across multiple cancers.

Prognostic markers and tumour growth kinetics in melanoma patients progressing on vemurafenib.

PubMed

Seifert, Heike; Fisher, Rosalie; Martin-Liberal, Juan; Edmonds, Kim; Hughes, Peta; Khabra, Komel; Gore, Martin; Larkin, James

2016-04-01

The BRAF inhibitor vemurafenib is an effective drug in patients with BRAF mutant metastatic melanoma, but resistance occurs after a median of 6 months. The anti-CTLA4-antibody, ipilimumab, is a standard first-line and second-line treatment option in Europe, with a median time to response of 2-3 months, but some patients show rapid clinical deterioration before that. The aim of this analysis was to identify prognostic markers for survival after failure of vemurafenib treatment to identify patients who have a sufficient life expectancy to respond to new immunotherapy treatments. We retrospectively analysed 101 consecutive unselected patients treated with vemurafenib for metastatic melanoma at a single institution. The association between clinical parameters and death within 3 months after cessation of vemurafenib (n=69) was assessed by binary logistic and Cox regression. Of the patients, 45% died within 3 months of progression on vemurafenib. Elevated baseline serum lactate dehydrogenase, absence of normalization of serum lactate dehydrogenase on vemurafenib therapy, performance status of at least 2 at progression and time from primary tumour to metastatic disease less than 5 years were identified as poor prognostic markers. In an exploratory tumour growth kinetics analysis (n=16), we found that following cessation of vemurafenib, approximately a third each showed a stable, decelerated or accelerated rate of tumour growth. Patients with these poor prognostic markers are unlikely to have sufficient life expectancy to complete ipilimumab treatment after failure with vemurafenib. Consideration needs to be given to the elective use of immunotherapy before patients become resistant to vemurafenib. This requires prospective randomized evaluation. Our tumour growth kinetics analysis requires confirmation; however, it may suggest that intermittent vemurafenib treatment should be investigated in clinical trials.