1
|
Characterization and clinical relevance of PDGFRA pathway copy number variation gains across human cancers. Mol Genet Genomics 2022; 297:561-571. [PMID: 35212838 PMCID: PMC8960564 DOI: 10.1007/s00438-022-01860-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/22/2022] [Indexed: 12/04/2022]
Abstract
We investigated the copy number variation (CNV) of PDGFRA pathway across all common cancer types as well as its clinical relevance. This study included a total of 10,678 patients with pan-cancerous species involving 33 types of cancers and patient information was obtained from The Cancer Genome Atlas. According to the PDGFRA pathway CNV, all samples were divided into copy number gain (CN gain) group and No CN gain group. The analysis of loss of heterozygosity (LOH) fraction, CNV burden, tumor mutation burden (TMB), and the number of immunogenic mutations were performed, as well as the correlation analysis of PDGFRA pathway CN gain with tumor-related signaling pathways and tumor-infiltrating immune cell subpopulations. The results showed that CN gain of PDGFRA pathway in the cancer patients was associated with significantly shorter overall survival. The CN gain of PDGFRA pathway was identified as a prognostic risk factor for some tumors. CN gain was accompanied by an altered percentage of LOH, CNV burden, TMB, the number of immunogenic mutations were increased and tumor-infiltrating immune cell subpopulations were less. While certain tumor-related signaling pathways, such as hypoxia, cell cycle, DNA repair, and epithelial-mesenchymal transition were more enriched in the CN gain group, quiescence, and inflammation pathways were more enriched in the No CN gain group. In conclusion, PDGFRA pathway CNV gain may be a poor prognostic factor in cancer patients.
Collapse
|
2
|
Global management of brain metastasis from renal cell carcinoma. Crit Rev Oncol Hematol 2022; 171:103600. [DOI: 10.1016/j.critrevonc.2022.103600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Revised: 12/28/2021] [Accepted: 01/17/2022] [Indexed: 11/20/2022] Open
|
3
|
Fu J, Su X, Li Z, Deng L, Liu X, Feng X, Peng J. HGF/c-MET pathway in cancer: from molecular characterization to clinical evidence. Oncogene 2021; 40:4625-4651. [PMID: 34145400 DOI: 10.1038/s41388-021-01863-w] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/17/2021] [Accepted: 05/24/2021] [Indexed: 02/07/2023]
Abstract
This review provides a comprehensive landscape of HGF/c-MET (hepatocyte growth factor (HGF) /mesenchymal-epithelial transition factor (c-MET)) signaling pathway in cancers. First, we generalize the compelling influence of HGF/c-MET pathway on multiple cellular processes. Then, we present the genomic characterization of HGF/c-MET pathway in carcinogenesis. Furthermore, we extensively illustrate the malignant biological behaviors of HGF/c-MET pathway in cancers, in which hyperactive HGF/c-MET signaling is considered as a hallmark. In addition, we investigate the current clinical trials of HGF/c-MET-targeted therapy in cancers. We find that although HGF/c-MET-targeted therapy has led to breakthroughs in certain cancers, monotherapy of targeting HGF/c-MET has failed to demonstrate significant clinical efficacy in most cancers. With the advantage of the combinations of HGF/c-MET-targeted therapy, the exploration of more options of combinational targeted therapy in cancers may be the major challenge in the future.
Collapse
Affiliation(s)
- Jianjiang Fu
- Department of Pathology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,The Third Clinical School of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, China
| | - Xiaorui Su
- Department of Pathology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,The Third Clinical School of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, China
| | - Zhihua Li
- The Third Clinical School of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, China.,Department of Fetal Medicine and Prenatal Diagnosis, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Ling Deng
- Department of Molecular Diagnostics, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Xiawei Liu
- Department of Pathology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.,The Third Clinical School of Guangzhou Medical University, Guangzhou, China.,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, China
| | - Xuancheng Feng
- Department of Pathology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. .,The Third Clinical School of Guangzhou Medical University, Guangzhou, China. .,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, China.
| | - Juan Peng
- Department of Pathology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. .,The Third Clinical School of Guangzhou Medical University, Guangzhou, China. .,Key Laboratory of Reproduction and Genetics of Guangdong Higher Education Institutes, Guangzhou, China.
| |
Collapse
|
4
|
Li R, Luo S, Zhang D. Circular RNA hsa_circ_0054537 sponges miR-130a-3p to promote the progression of renal cell carcinoma through regulating cMet pathway. Gene 2020; 754:144811. [PMID: 32464246 DOI: 10.1016/j.gene.2020.144811] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 05/10/2020] [Accepted: 05/22/2020] [Indexed: 02/07/2023]
Abstract
Renal cell carcinoma (RCC) is one of the most common tumors of the urinary system, seriously impacting public health. CircRNAs have been indicated as potentially critical mediators in tumorigenesis and cancer progression. However, their specific role in the metastasis of RCC remains unclear. In present study, we identified that miR-130a-3p presented aberrantly low-level in RCC cells. Furthermore, it was demonstrated that upregulated miR-130a-3p suppressed the proliferation and migration of cell and promoted cell apoptosis in RCC. Then we predicted the underlyingly upstream modulator of miR-130a-3p was a novel circRNA hsa_circ_0054537, which exhibited dysregulated in RCC cells. Subsequently, we confirmed the direct interaction between hsa_circ_0054537 and miR-130a-3p by RNA pulldown assay. Additionally, luciferase assay confirmed the correlation between hsa_circ_0054537 and miR-130a-3p at the transcriptional level. We also found hsa_circ_0054537 could affect the tumorigenesis through binding to miR-130a-3p competitively. In addition, we identified the target of miR-130a-3p was oncogene cMet, which could be co-controlled by hsa_circ_0054537 and miR-130a-3p. In conclusion, we demonstrated that circRNA hsa_circ_0054537 functioned as a competitive endogenous RNA to regulate cMet expression via sponging miR-130a-3p in renal cancer.
Collapse
Affiliation(s)
- Rui Li
- Department of Urology, Xiangyang No.1 People's Hospital, Hubei University of Medicine, Xiangyang, China
| | - Sheng Luo
- Department of Urology, Xiangyang No.1 People's Hospital, Hubei University of Medicine, Xiangyang, China
| | - Dahu Zhang
- Department of Urology, Xiangyang No.1 People's Hospital, Hubei University of Medicine, Xiangyang, China.
| |
Collapse
|
5
|
Moosavi F, Giovannetti E, Saso L, Firuzi O. HGF/MET pathway aberrations as diagnostic, prognostic, and predictive biomarkers in human cancers. Crit Rev Clin Lab Sci 2019; 56:533-566. [PMID: 31512514 DOI: 10.1080/10408363.2019.1653821] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cancer is a major cause of death worldwide. MET tyrosine kinase receptor [MET, c-MET, hepatocyte growth factor (HGF) receptor] pathway activation is associated with the appearance of several hallmarks of cancer. The HGF/MET pathway has emerged as an important actionable target across many solid tumors; therefore, biomarker discovery becomes essential in order to guide clinical intervention and patient stratification with the aim of moving towards personalized medicine. The focus of this review is on how the aberrant activation of the HGF/MET pathway in tumor tissue or the circulation can provide diagnostic and prognostic biomarkers and predictive biomarkers of drug response. Many meta-analyses have shown that aberrant activation of the MET pathway in tumor tissue, including MET gene overexpression, gene amplification, exon 14 skipping and other activating mutations, is almost invariably associated with shorter survival and poor prognosis. Most meta-analyses have been performed in non-small cell lung cancer (NSCLC), breast, head and neck cancers as well as colorectal, gastric, pancreatic and other gastrointestinal cancers. Furthermore, several studies have shown the predictive value of MET biomarkers in the identification of patients who gain the most benefit from HGF/MET targeted therapies administered as single or combination therapies. The highest predictive values have been observed for response to foretinib and savolitinib in renal cancer, as well as tivantinib in NSCLC and colorectal cancer. However, some studies, especially those based on MET expression, have failed to show much value in these stratifications. This may be rooted in lack of standardization of methodologies, in particular in scoring systems applied in immunohistochemistry determinations or absence of oncogenic addiction of cancer cells to the MET pathway, despite detection of overexpression. Measurements of amplification and mutation aberrations are less likely to suffer from these pitfalls. Increased levels of MET soluble ectodomain (sMET) in circulation have also been associated with poor prognosis; however, the evidence is not as strong as it is with tissue-based biomarkers. As a diagnostic biomarker, sMET has shown its value in distinguishing cancer patients from healthy individuals in prostate and bladder cancers and in melanoma. On the other hand, increased circulating HGF has also been presented as a valuable prognostic and diagnostic biomarker in many cancers; however, there is controversy on the predictive value of HGF as a biomarker. Other biomarkers such as circulating tumor DNA (ctDNA) and tumor HGF levels have also been briefly covered. In conclusion, HGF/MET aberrations can provide valuable diagnostic, prognostic and predictive biomarkers and represent vital assets for personalized cancer therapy.
Collapse
Affiliation(s)
- Fatemeh Moosavi
- Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences , Shiraz , Iran
| | - Elisa Giovannetti
- Department of Medical Oncology, Cancer Center Amsterdam, Amsterdam UMC, VU University Medical Center (VUmc) , Amsterdam , The Netherlands.,Cancer Pharmacology Lab, AIRC Start Up Unit, Fondazione Pisana per la Scienza Onlus , Pisa , Italy
| | - Luciano Saso
- Department of Physiology and Pharmacology, "Vittorio Erspamer," Sapienza University , Rome , Italy
| | - Omidreza Firuzi
- Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences , Shiraz , Iran
| |
Collapse
|
6
|
Négrier S, Moriceau G, Attignon V, Haddad V, Pissaloux D, Guerin N, Carrie C. Activity of cabozantinib in radioresistant brain metastases from renal cell carcinoma: two case reports. J Med Case Rep 2018; 12:351. [PMID: 30474572 PMCID: PMC6260776 DOI: 10.1186/s13256-018-1875-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 10/08/2018] [Indexed: 02/05/2023] Open
Abstract
Background Renal cell carcinoma represents 3–5% of adult malignant tumors. Metastases are found in 30–40% of patients and brain metastases occurred in more than 10% of them. Despite significant progress in medical treatment, patients with brain metastases still have a limited survival. Cabozantinib, a tyrosine kinase inhibitor directed against vascular endothelial growth factor receptors, was recently registered for the treatment of metastatic renal cell carcinoma. Almost no data are, however, available on patients with brain metastases. Case presentation Case 1 is a 51-year-old man of North African origin; Case 2 is a 55-year-old European man. Case 1 and Case 2 had metastases of renal carcinoma at initial diagnosis and were treated with vascular endothelial growth factor receptors tyrosine kinase inhibitors. Case 1 had clear cell renal carcinoma and underwent nephrectomy; he then received several lines of tyrosine kinase inhibitor directed against vascular endothelial growth factor receptors and the mTor complex. During the second treatment a brain metastasis was diagnosed and treated with radiosurgery with rapid efficacy. Two years later he received nivolumab, an antibody directed against the programmed death-1 and programmed death-ligand 1 complex, but disease progression was observed with the reappearance of the brain metastasis together with neurologic symptoms. Cabozantinib was administered and induced a rapid clinical improvement as well as tumor regression in all sites including his brain. Sequencing of his tumor evidenced a mutation of the MET gene. Case 2 had a papillary renal carcinoma with brain metastases at time of diagnosis. After radiation of the brain tumors, a vascular endothelial growth factor receptor tyrosine kinase inhibitor was administered for 3 years. The disease was under control in all sites except in his brain; several new brain metastases requiring new radiation treatments developed. The disease finally progressed at all metastatic sites including his brain and he had several neurological symptoms. Cabozantinib was administered and rapidly induced a clinical improvement; a further computed tomography scan and brain magnetic resonance imaging showed significant tumor regressions. No MET gene mutation or amplification was observed in the tumor analysis. Conclusions These case reports indicate that cabozantinib was able, first, to reach brain tumors and second, to induce significant regressions in renal carcinoma brain metastases that were resistant to radiation as well as to previous systemic vascular endothelial growth factor receptor tyrosine kinase inhibitors.
Collapse
Affiliation(s)
- Sylvie Négrier
- Univ Lyon, Université Claude Bernard Lyon 1, Lyon, France. .,Department of Medical Oncology, Centre Léon Bérard, Lyon, France.
| | | | - Valéry Attignon
- Department of Translational Research and Innovation, Centre Léon Bérard, Lyon, France
| | | | | | - Nicole Guerin
- Department of Radiology, Centre Léon Bérard, Lyon, France
| | - Christian Carrie
- Department of Radiation Therapy, Centre Léon Bérard, Lyon, France
| |
Collapse
|
7
|
Dufies M, Giuliano S, Ambrosetti D, Claren A, Ndiaye PD, Mastri M, Moghrabi W, Cooley LS, Ettaiche M, Chamorey E, Parola J, Vial V, Lupu-Plesu M, Bernhard JC, Ravaud A, Borchiellini D, Ferrero JM, Bikfalvi A, Ebos JM, Khabar KS, Grépin R, Pagès G. Sunitinib Stimulates Expression of VEGFC by Tumor Cells and Promotes Lymphangiogenesis in Clear Cell Renal Cell Carcinomas. Cancer Res 2017; 77:1212-1226. [PMID: 28087600 DOI: 10.1158/0008-5472.can-16-3088] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 12/07/2016] [Accepted: 12/08/2016] [Indexed: 11/16/2022]
Abstract
Sunitinib is an antiangiogenic therapy given as a first-line treatment for renal cell carcinoma (RCC). While treatment improves progression-free survival, most patients relapse. We hypothesized that patient relapse can stem from the development of a lymphatic network driven by the production of the main growth factor for lymphatic endothelial cells, VEGFC. In this study, we found that sunitinib can stimulate vegfc gene transcription and increase VEGFC mRNA half-life. In addition, sunitinib activated p38 MAPK, which resulted in the upregulation/activity of HuR and inactivation of tristetraprolin, two AU-rich element-binding proteins. Sunitinib stimulated a VEGFC-dependent development of lymphatic vessels in experimental tumors. This may explain our findings of increased lymph node invasion and new metastatic sites in 30% of sunitinib-treated patients and increased lymphatic vessels found in 70% of neoadjuvant treated patients. In summary, a therapy dedicated to destroying tumor blood vessels induced the development of lymphatic vessels, which may have contributed to the treatment failure. Cancer Res; 77(5); 1212-26. ©2017 AACR.
Collapse
Affiliation(s)
- Maeva Dufies
- University of Nice Sophia Antipolis, Institute for Research on Cancer and Aging of Nice, CNRS UMR 7284, INSERM U1081, Centre Antoine Lacassagne, Nice, France
| | - Sandy Giuliano
- University of Nice Sophia Antipolis, Institute for Research on Cancer and Aging of Nice, CNRS UMR 7284, INSERM U1081, Centre Antoine Lacassagne, Nice, France
- Biomedical Department, Centre Scientifique de Monaco, Monaco, Principality of Monaco
| | - Damien Ambrosetti
- Central Laboratory of Pathology, Centre Hospitalier Universitaire (CHU) de Nice, Hôpital Pasteur, Nice, France
| | - Audrey Claren
- University of Nice Sophia Antipolis, Institute for Research on Cancer and Aging of Nice, CNRS UMR 7284, INSERM U1081, Centre Antoine Lacassagne, Nice, France
- Radiotherapy Department, Centre Antoine Lacassagne, Nice, France
| | - Papa Diogop Ndiaye
- University of Nice Sophia Antipolis, Institute for Research on Cancer and Aging of Nice, CNRS UMR 7284, INSERM U1081, Centre Antoine Lacassagne, Nice, France
| | - Michalis Mastri
- Center for Genetics and Pharmacology, Roswell Park Cancer Institute, Buffalo, New York
| | - Walid Moghrabi
- King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | | | - Marc Ettaiche
- Statistics Department, Centre Antoine Lacassagne, Nice, France
| | | | - Julien Parola
- University of Nice Sophia Antipolis, Institute for Research on Cancer and Aging of Nice, CNRS UMR 7284, INSERM U1081, Centre Antoine Lacassagne, Nice, France
| | - Valerie Vial
- Biomedical Department, Centre Scientifique de Monaco, Monaco, Principality of Monaco
| | - Marilena Lupu-Plesu
- University of Nice Sophia Antipolis, Institute for Research on Cancer and Aging of Nice, CNRS UMR 7284, INSERM U1081, Centre Antoine Lacassagne, Nice, France
| | | | - Alain Ravaud
- Service d'Oncologie Médicale, Centre Hospitalier Universitaire (CHU) de Bordeaux, Bordeaux, France
| | | | | | | | - John M Ebos
- Center for Genetics and Pharmacology, Roswell Park Cancer Institute, Buffalo, New York
| | - Khalid Saad Khabar
- King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
| | - Renaud Grépin
- Biomedical Department, Centre Scientifique de Monaco, Monaco, Principality of Monaco
| | - Gilles Pagès
- University of Nice Sophia Antipolis, Institute for Research on Cancer and Aging of Nice, CNRS UMR 7284, INSERM U1081, Centre Antoine Lacassagne, Nice, France.
| |
Collapse
|
8
|
Macher-Goeppinger S, Keith M, Endris V, Penzel R, Tagscherer KE, Pahernik S, Hohenfellner M, Gardner H, Grüllich C, Schirmacher P, Roth W. MET expression and copy number status in clear-cell renal cell carcinoma: prognostic value and potential predictive marker. Oncotarget 2017; 8:1046-1057. [PMID: 27894094 PMCID: PMC5352033 DOI: 10.18632/oncotarget.13540] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 11/07/2016] [Indexed: 12/12/2022] Open
Abstract
Multiple targeted therapy for advanced clear-cell renal cell carcinoma (RCC) has substantially improved patient outcome, but complete remission is uncommon and many tumors eventually develop resistance. Mechanistic, preclinical, and early clinical data highlight c-Met / hepatocyte growth factor receptor as a promising target for RCC therapeutic agents.We have examined MET expression, frequency of MET gene copy gains and MET gene mutation in a large, hospital-based series of renal cell carcinomas with long-term follow-up information.Out of a total of 572 clear-cell RCC, only 17% were negative for MET expression whereas 32% showed high protein levels. High MET expression and MET copy number gains were associated with an aggressive phenotype and an unfavorable patient outcome. Elevated protein levels in absence of gene amplification were not attributed to mutations, based on results of targeted next-generation sequencing.Our data reveal that clear-cell RCC with MET upregulation show an aggressive behavior and MET copy number increase is evident in a substantial percentage of patients with high-grade carcinomas and metastatic disease. Diagnostic assessment of MET expression and amplification may be of predictive value to guide targeted therapy against MET signaling in patients with clear-cell RCC.
Collapse
Affiliation(s)
- Stephan Macher-Goeppinger
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
- Molecular Tumor Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Institute of Pathology, University Medical Center Mainz, Mainz, Germany
| | - Martina Keith
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
- Molecular Tumor Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Volker Endris
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
| | - Roland Penzel
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
| | - Katrin E. Tagscherer
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
- Molecular Tumor Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Sascha Pahernik
- Department of Urology, University Hospital Heidelberg, Heidelberg, Germany
| | | | - Humphrey Gardner
- Translational Medicine, Early Clinical Development, AstraZeneca, Gatehouse Park, Waltham, MA, USA
| | - Carsten Grüllich
- Department of Medical Oncology, National Center for Tumor Diseases Heidelberg, University Hospital Heidelberg, Heidelberg, Germany
| | - Peter Schirmacher
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
| | - Wilfried Roth
- Institute of Pathology, University Hospital Heidelberg, Heidelberg, Germany
- Molecular Tumor Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Institute of Pathology, University Medical Center Mainz, Mainz, Germany
| |
Collapse
|
9
|
Profiling of cMET and HER Family Receptor Expression in Pancreatic Ductal Adenocarcinomas and Corresponding Lymph Node Metastasis to Assess Relevant Pathways for Targeted Therapies: Looking at the Soil Before Planting the Seed. Pancreas 2016; 45:1167-74. [PMID: 26825865 DOI: 10.1097/mpa.0000000000000604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVES Comprehensive assessment of cMET and HER family receptor tyrosine kinases expression, changes of expression during metastatic progression, amplification status of the MET gene, and correlations with patient characteristics in pancreatic ductal adenocarcinoma (PDAC) was conducted. METHODS We investigated 56 PDACs and corresponding lymph node metastases for HER1 to HER4 and cMET expression by immunohistochemistry, as well as cMET gene copy numbers by chromogenic in situ hybridization. RESULTS Of all receptor tyrosine kinases evaluated, cMET expression was highest with 46.5% of tumors showing moderate or strong expression and a weak correlation with gene copy number status (P = 0.04; Spearman ρ = 0.28). cMET expression was increased in metastases. In contrast, expression levels of HER family receptors were generally low both in primaries and metastases. A weak yet significant correlation of HER1 and cMET expression levels was observed (P < 0.001; Spearman ρ = 0.44) and HER1 was often present in poorly differentiated tumors (G3, P = 0.049). CONCLUSIONS Our data suggest that cMET might constitute an interesting molecule for combining targeted and chemotherapeutic approaches in PDAC, because expression is frequent and increased during metastatic progression. In PDAC, cMET protein expression might be a more useful stratification biomarker than cMET gene amplification, which does not seem to be its primary regulator.
Collapse
|