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Kim HR, Lee SJ, Ahn MS, Kim JE, Kang MJ, Hong JY, Lee J, Kim ST. Imatinib in c-KIT-mutated metastatic solid tumors: A multicenter trial of Korean Cancer Study Group (UN18-05 Trial). J Cancer Res Ther 2024; 20:972-978. [PMID: 39023605 DOI: 10.4103/jcrt.jcrt_2698_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Accepted: 01/03/2023] [Indexed: 07/20/2024]
Abstract
INTRODUCTION We conducted an open-label, single-arm, multi-center phase II trial to evaluate the efficacy and safety of imatinib chemotherapy-refractory or metastatic solid tumor patients with c-KIT mutations and/or amplification. METHODS c-KIT mutations and amplification were detected using NGS. Imatinib (400 mg daily) was administered continuously in 28-day cycles until disease progression, unacceptable adverse events, or death by any cause. The primary endpoint was the objective response rate (ORR). RESULT In total, 18 patients were enrolled on this trial. The most common tumor type was melanoma (n = 15, 83.3%), followed by ovarian cancer, breast cancer, and metastasis of unknown origin (MUO) (each n = 1, 5.5%). The total number of evaluable patients was 17, of which one patient had a complete response, six patients had partial response, and two patients had stable disease. The overall response rate (ORR) of 41.2% (95% CI 17.80-64.60) and a disease control rate of 52.9% (95% CI 29.17-76.63). The median progression-free survival was 2.2 months (95% CI 1.29-3.20), and median overall survival was 9.1 months (95% CI 2.10-16.11). The most common adverse events were edema (31.3%), anorexia (25.0%), nausea (18.8%), and skin rash (18.8%). CONCLUSION Imatinib demonstrated modest anti-tumor activity and a manageable safety profile in chemotherapy-refractory solid tumors with c-KIT mutation, especially in melanoma patients.
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Affiliation(s)
- Hye Ryeon Kim
- Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Department of Internal Medicine, Dong-A University College of Medicine, Busan, Korea
| | - Su Jin Lee
- Division of Hematology-Oncology, Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, Korea
| | - Mi Sun Ahn
- Division of Hematology/Oncology, Department of Medicine, Ajou University Medical Center, Suwon, Korea
| | - Jeong Eun Kim
- Department of Oncology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea
| | - Myoung Joo Kang
- Division of Oncology, Department of Internal Medicine, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Korea
| | - Jung Yong Hong
- Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jeeyun Lee
- Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Seung Tae Kim
- Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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2
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Shekhawat RS, Meshram VP, Rao M, Shedge R, Panwar R, Rathore M, Kanchan T. Further explorations into the role of mast cells in deaths associated with fatal asphyxia: an immunohistochemical study utilizing CD 117 marker. Forensic Sci Int 2023; 350:111689. [PMID: 37478731 DOI: 10.1016/j.forsciint.2023.111689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 03/02/2023] [Accepted: 04/11/2023] [Indexed: 07/23/2023]
Abstract
Asphyxia-related deaths have always been a challenging task in the speciality of forensic pathology. Apart from helpful macroscopical signs (e.g., strangulation mark, cyanosis, petechial haemorrhage, and lung oedema), recent literature indicates that prolonged asphyxia is sufficient to induce an increase in mast cells (MC). Inflammatory cells migrate from the bone marrow to the lungs, aiding in the diagnosis of fatal asphyxial deaths. HIF1-α, a key regulator protein, is released from lung tissue capillaries during catastrophic hypoxia circumstances, as previously demonstrated in immunohistochemistry (IHC) research. The present study analyzed lung samples from 164 medico-legal autopsy cases, including 57 asphyxia/hypoxia deaths and 107 controls (non-asphyxial deaths). Peribronchial, perivascular and perialveolar MCs were detected using CD117 antibody, and the average of MCs in each of these locations was noted in each case. The results indicated a statistically significant increase in peribronchial and perialveolar mast cells (MC) in fatal asphyxial deaths, including those caused by hanging, drowning, or postural asphyxia. Peri-bronchial MC in lung sections of asphyxial deaths were in the range of 0.2-5.4 and in non-asphyxial samples were in the range of 0.0-2.2. Peri-alveolar MCs in lung sections of asphyxial deaths were in the range of 0.0-0.6 and in non-asphyxial samples were in the range of 0.0-0.2. Our data suggest that mast cells (MC) play an important role in fatal hypoxia-related mortality and CD 117 may be a reliable marker for detection of mast cells in asphyxial deaths. It could be very beneficial to forensic pathologists tasked with differentiating fatal asphyxia fatalities from other causes of death.
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Affiliation(s)
- Raghvendra Singh Shekhawat
- Department of Forensic Medicine and Toxicology, All India Institute of Medical Sciences, Jodhpur 342005, India.
| | - Vikas P Meshram
- Department of Forensic Medicine and Toxicology, All India Institute of Medical Sciences, Jodhpur, India
| | - Meenakshi Rao
- Department of Pathology and Lab Medicine, All India Institute of Medical Sciences, Jodhpur, India
| | - Rutwik Shedge
- Department of Forensic Science, National Forensic Sciences University, Tripura, India
| | - Rahul Panwar
- Department of Forensic Medicine and Toxicology, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Mohini Rathore
- Department of Biochemistry, All India Institute of Medical Sciences, Jodhpur, Rajasthan, India
| | - Tanuj Kanchan
- Department of Forensic Medicine and Toxicology, All India Institute of Medical Sciences, Jodhpur, India
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3
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Maroni P. Leptin, Adiponectin, and Sam68 in Bone Metastasis from Breast Cancer. Int J Mol Sci 2020; 21:ijms21031051. [PMID: 32033341 PMCID: PMC7037668 DOI: 10.3390/ijms21031051] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/03/2020] [Accepted: 02/04/2020] [Indexed: 12/12/2022] Open
Abstract
The most serious aspect of neoplastic disease is the spread of cancer cells to secondary sites. Skeletal metastases can escape detection long after treatment of the primary tumour and follow-up. Bone tissue is a breeding ground for many types of cancer cells, especially those derived from the breast, prostate, and lung. Despite advances in diagnosis and therapeutic strategies, bone metastases still have a profound impact on quality of life and survival and are often responsible for the fatal outcome of the disease. Bone and the bone marrow environment contain a wide variety of cells. No longer considered a passive filler, bone marrow adipocytes have emerged as critical contributors to cancer progression. Released by adipocytes, adipokines are soluble factors with hormone-like functions and are currently believed to affect tumour development. Src-associated in mitosis of 68 kDa (Sam68), originally discovered as a protein physically associated with and phosphorylated by c-Src during mitosis, is now recognised as an important RNA-binding protein linked to tumour onset and progression of disease. Sam68 also regulates splicing events and recent evidence reports that dysregulation of these events is a key step in neoplastic transformation and tumour progression. The present review reports recent findings on adipokines and Sam68 and their role in breast cancer progression and metastasis.
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Affiliation(s)
- Paola Maroni
- IRCCS Istituto Ortopedico Galeazzi, Via R. Galeazzi 4, 20161 Milano, Italy
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4
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El-Houseini ME, Ismail A, Abdelaal AA, El-Habashy AH, Abdallah ZF, Mohamed MZ, El-Hadidi M, Cho WCS, Ahmed H, Al-Shafie TA. Role of TGF-β1 and C-Kit Mutations in the Development of Hepatocellular Carcinoma in Hepatitis C Virus-Infected Patients: in vitro Study. BIOCHEMISTRY (MOSCOW) 2019; 84:941-953. [PMID: 31522676 DOI: 10.1134/s0006297919080108] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Transforming growth factor beta (TGF-β) acts as a tumor-suppressing cytokine in healthy tissues and non-malignant tumors. Yet, in malignancy, TGF-β can exert the opposite effects that can promote proliferation of cancer cells. C-Kit plays a prominent role in stem cell activation and liver regeneration after injury. However, little is known about the cross-talk between TGF-β and C-Kit and its role in the progression of hepatocellular carcinoma (HCC). Here, we studied the effect of increasing doses of TGF-β1 on CD44+CD90+ liver stem cells (LSCs) and C-Kit gene expression in malignant and adjacent non-malignant liver tissues excised from 32 HCC patients. The percentage of LSCs in malignant tumors was two times higher compared to their counterparts from the non-malignant tissues. When treated with increasing doses of TGF-β1, proliferation of both malignant and non-malignant LSCs was progressively suppressed, but low TGF-β1 dose failed to suppress the growth of malignant LSCs. Moreover, C-Kit exons 9 and 11 were expressed in malignant LSCs, but not in their non-malignant counterparts. Analysis of C-Kit detected mutations in exon 9 (but not in exon 11) in some malignant liver cells resulting in the changes in the amino acid sequence and dysregulation of protein structure and function. Interestingly, in malignant liver cells, mutations in exon 9 were associated with high-viremia hepatitis C virus (HCV), and expression of this exon was not suppressed by the TGF-β1 treatment at all doses. To our knowledge, this is the first report that mutations in the C-Kit gene in HCC patients are associated with high- viremia HCV. Our study emphasizes the need for investigation of the TGF-β1 level and C-Kit mutations in patients with chronic HCV for HCC prevention and better therapy management.
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Affiliation(s)
- M E El-Houseini
- Cairo University, National Cancer Institute, Department of Cancer Biology, Cairo, 11796, Egypt
| | - A Ismail
- Ain Shams University, Faculty of Medicine, Department of Surgery, Cairo, 11566, Egypt
| | - A A Abdelaal
- Ain Shams University, Faculty of Medicine, Department of Surgery, Cairo, 11566, Egypt
| | - A H El-Habashy
- Cairo University, National Cancer Institute, Department of Pathology, Cairo, 11796, Egypt
| | - Z F Abdallah
- Cairo University, National Cancer Institute, Department of Cancer Biology, Cairo, 11796, Egypt
| | - M Z Mohamed
- Medical Center of Egyptian Railways, Department of Medical Laboratory, Cairo, 11669, Egypt
| | - M El-Hadidi
- Nile University, Center of Informatics Science, Giza, 12525, Egypt
| | - W C S Cho
- Queen Elizabeth Hospital, Department of Clinical Oncology, Kowloon, Hong Kong, China
| | - H Ahmed
- GlycoMantra, Inc., Baltimore, MD 21227, USA
| | - T A Al-Shafie
- Cairo University, National Cancer Institute, Department of Cancer Biology, Cairo, 11796, Egypt. .,Pharos University in Alexandria, Faculty of Pharmacy and Drug Manufacturing, Department of Pharmacology and Therapeutics, Alexandria, 21311, Egypt
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5
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Ergün S, Altay DU, Güneş S, Büyükalpelli R, Karahan SC, Tomak L, Abur Ü. Tr-KIT/c-KIT ratio in renal cell carcinoma. Mol Biol Rep 2019; 46:5287-5294. [DOI: 10.1007/s11033-019-04985-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 07/17/2019] [Indexed: 01/08/2023]
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6
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Paratala BS, Chung JH, Williams CB, Yilmazel B, Petrosky W, Williams K, Schrock AB, Gay LM, Lee E, Dolfi SC, Pham K, Lin S, Yao M, Kulkarni A, DiClemente F, Liu C, Rodriguez-Rodriguez L, Ganesan S, Ross JS, Ali SM, Leyland-Jones B, Hirshfield KM. RET rearrangements are actionable alterations in breast cancer. Nat Commun 2018; 9:4821. [PMID: 30446652 PMCID: PMC6240119 DOI: 10.1038/s41467-018-07341-4] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 10/25/2018] [Indexed: 11/23/2022] Open
Abstract
Fusions involving the oncogenic gene RET have been observed in thyroid and lung cancers. Here we report RET gene alterations, including amplification, missense mutations, known fusions, novel fusions, and rearrangements in breast cancer. Their frequency, oncogenic potential, and actionability in breast cancer are described. Two out of eight RET fusions (NCOA4-RET and a novel RASGEF1A-RET fusion) and RET amplification were functionally characterized and shown to activate RET kinase and drive signaling through MAPK and PI3K pathways. These fusions and RET amplification can induce transformation of non-tumorigenic cells, support xenograft tumor formation, and render sensitivity to RET inhibition. An index case of metastatic breast cancer progressing on HER2-targeted therapy was found to have the NCOA4-RET fusion. Subsequent treatment with the RET inhibitor cabozantinib led to a rapid clinical and radiographic response. RET alterations, identified by genomic profiling, are promising therapeutic targets and are present in a subset of breast cancers. Fusions of the gene RET have been described in thyroid and lung cancers. Here, the AUs identify RET gene alterations, including known fusions, novel fusions, and rearrangements in breast cancer (BC) that are involved in the tumorigenic process and show the benefit of RET therapy in a recurrent BC patient carrying the NCOA4-RET fusion.
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Affiliation(s)
- Bhavna S Paratala
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | - Jon H Chung
- Foundation Medicine, Cambridge, MA, 02139, USA
| | - Casey B Williams
- Avera Cancer Institute Center for Precision Oncology, Sioux Falls, SD, 57105, USA
| | | | - Whitney Petrosky
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | - Kirstin Williams
- Avera Cancer Institute Center for Precision Oncology, Sioux Falls, SD, 57105, USA
| | | | | | - Ellen Lee
- University Radiology Group, New Brunswick, NJ, 08901, USA
| | - Sonia C Dolfi
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | - Kien Pham
- Department of Pathology and Laboratory Medicine, Rutgers New Jersey Medical School and Rutgers Robert Wood Johnson Medical School, Newark, NJ, 07103, USA
| | - Stephanie Lin
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | - Ming Yao
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | - Atul Kulkarni
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | - Frances DiClemente
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | - Chen Liu
- Department of Pathology and Laboratory Medicine, Rutgers New Jersey Medical School and Rutgers Robert Wood Johnson Medical School, Newark, NJ, 07103, USA
| | - Lorna Rodriguez-Rodriguez
- Rutgers University, Piscataway, NJ, 08854, USA.,Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA
| | - Shridar Ganesan
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA.,Rutgers University, Piscataway, NJ, 08854, USA
| | | | - Siraj M Ali
- Foundation Medicine, Cambridge, MA, 02139, USA
| | - Brian Leyland-Jones
- Avera Cancer Institute Center for Precision Oncology, Sioux Falls, SD, 57105, USA.
| | - Kim M Hirshfield
- Department of Medicine, Division of Medical Oncology, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, 08901, USA. .,Rutgers University, Piscataway, NJ, 08854, USA.
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7
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Li N, Ngo CTA, Aleynikova O, Beauchemin N, Richard S. The p53 status can influence the role of Sam68 in tumorigenesis. Oncotarget 2018; 7:71651-71659. [PMID: 27690217 PMCID: PMC5342108 DOI: 10.18632/oncotarget.12305] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 09/20/2016] [Indexed: 02/02/2023] Open
Abstract
The expression and activities of RNA binding proteins are frequently dysregulated in human cancer. Their roles, however, appears to be complex, with reports indicating both pro-tumorigenic and tumor suppressive functions. Here we show, using two classical mouse cancer models, that the role of KH-type RNA binding protein, Sam68, in tumor development can be influenced by the status of the p53 tumor suppressor. We demonstrate that in mice expressing wild type p53, Sam68-deficiency resulted in a higher incidence and malignancy of carcinogen-induced tumors, suggesting a tumor suppressive role for Sam68. In marked contrast, Sam68-haploinsufficiency significantly delayed the onset of tumors in mice lacking p53 and prolonged their survival, indicating that Sam68 accelerates the development of p53-deficient tumors. These findings provide considerable insight into a previously unknown relationship between Sam68 and the p53 tumor suppressor in tumorigenesis.
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Affiliation(s)
- Naomi Li
- Terry Fox Molecular Oncology Group and the Bloomfield Center for Research on Aging, Sir Mortimer B Davis Jewish General Hospital, Lady Davis Institute for Medical Research, Montréal, Québec H3T 1E2, Canada.,Department of Medicine and Oncology, McGill University, Montréal, Québec H3A 1A1, Canada
| | - Chau Tuan-Anh Ngo
- Terry Fox Molecular Oncology Group and the Bloomfield Center for Research on Aging, Sir Mortimer B Davis Jewish General Hospital, Lady Davis Institute for Medical Research, Montréal, Québec H3T 1E2, Canada.,Department of Medicine and Oncology, McGill University, Montréal, Québec H3A 1A1, Canada
| | - Olga Aleynikova
- Department of Pathology, Jewish General Hospital, Montréal, Québec H3T 1E2, Canada
| | - Nicole Beauchemin
- Department of Medicine and Oncology, McGill University, Montréal, Québec H3A 1A1, Canada.,Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada.,Rosalind and Morris Goodman Cancer Centre, Montréal, Québec H3A 1A3, Canada
| | - Stéphane Richard
- Terry Fox Molecular Oncology Group and the Bloomfield Center for Research on Aging, Sir Mortimer B Davis Jewish General Hospital, Lady Davis Institute for Medical Research, Montréal, Québec H3T 1E2, Canada.,Department of Medicine and Oncology, McGill University, Montréal, Québec H3A 1A1, Canada
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8
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Figueira MI, Cardoso HJ, Correia S, Maia CJ, Socorro S. The stem cell factor (SCF)/c-KIT system in carcinogenesis of reproductive tissues: What does the hormonal regulation tell us? Cancer Lett 2017; 405:10-21. [DOI: 10.1016/j.canlet.2017.07.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 07/15/2017] [Accepted: 07/17/2017] [Indexed: 12/13/2022]
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9
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The stem cell factor (SCF)/c-KIT signalling in testis and prostate cancer. J Cell Commun Signal 2017; 11:297-307. [PMID: 28656507 DOI: 10.1007/s12079-017-0399-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 06/15/2017] [Indexed: 01/17/2023] Open
Abstract
The stem cell factor (SCF) is a cytokine that specifically binds the tyrosine kinase receptor c-KIT. The SCF/c-KIT interaction leads to receptor dimerization, activation of kinase activity and initiation of several signal transduction pathways that control cell proliferation, apoptosis, differentiation and migration in several tissues. The activity of SCF/c-KIT system is linked with the phosphatidylinositol 3-kinase (PI3-K), the Src, the Janus kinase/signal transducers and activators of transcription (JAK/STAT), the phospholipase-C (PLC-γ) and the mitogen-activated protein kinase (MAPK) pathways. Moreover, it has been reported that cancer cases display an overactivation of c-KIT due to the presence of gain-of-function mutations or receptor overexpression, which renders c-KIT a tempting target for cancer treatment. In the case of male cancers the most documented activated pathways are the PI3-K and Src, both enhancing abnormal cell proliferation. It is also known that the Src activity in prostate cancer cases depends on the presence of tr-KIT, the cytoplasmic truncated variant of c-KIT that is specifically expressed in tumour tissues and, thus, a very interesting target for drug development. The present review provides an overview of the signalling pathways activated by SCF/c-KIT and discusses the potential application of c-KIT inhibitors for treatment of testicular and prostatic cancers.
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10
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Chattopadhyay I, Wang J, Qin M, Gao L, Holtz R, Vessella RL, Leach RW, Gelman IH. Src promotes castration-recurrent prostate cancer through androgen receptor-dependent canonical and non-canonical transcriptional signatures. Oncotarget 2017; 8:10324-10347. [PMID: 28055971 PMCID: PMC5354662 DOI: 10.18632/oncotarget.14401] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Accepted: 12/05/2016] [Indexed: 11/25/2022] Open
Abstract
Progression of prostate cancer (PC) to castration-recurrent growth (CRPC) remains dependent on sustained expression and transcriptional activity of the androgen receptor (AR). A major mechanism contributing to CRPC progression is through the direct phosphorylation and activation of AR by Src-family (SFK) and ACK1 tyrosine kinases. However, the AR-dependent transcriptional networks activated by Src during CRPC progression have not been elucidated. Here, we show that activated Src (Src527F) induces androgen-independent growth in human LNCaP cells, concomitant with its ability to induce proliferation/survival genes normally induced by dihydrotestosterone (DHT) in androgen-dependent LNCaP and VCaP cells. Src induces additional gene signatures unique to CRPC cell lines, LNCaP-C4-2 and CWR22Rv1, and to CRPC LuCaP35.1 xenografts. By comparing the Src-induced AR-cistrome and/or transcriptome in LNCaP to those in CRPC and LuCaP35.1 tumors, we identified an 11-gene Src-regulated CRPC signature consisting of AR-dependent, AR binding site (ARBS)-associated genes whose expression is altered by DHT in LNCaP[Src527F] but not in LNCaP cells. The differential expression of a subset (DPP4, BCAT1, CNTNAP4, CDH3) correlates with earlier PC metastasis onset and poorer survival, with the expression of BCAT1 required for Src-induced androgen-independent proliferation. Lastly, Src enhances AR binding to non-canonical ARBS enriched for FOXO1, TOP2B and ZNF217 binding motifs; cooperative AR/TOP2B binding to a non-canonical ARBS was both Src- and DHT-sensitive and correlated with increased levels of Src-induced phosphotyrosyl-TOP2B. These data suggest that CRPC progression is facilitated via Src-induced sensitization of AR to intracrine androgen levels, resulting in the engagement of canonical and non-canonical ARBS-dependent gene signatures.
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MESH Headings
- Androgen Antagonists/pharmacology
- Binding Sites
- Cell Line, Tumor
- Cell Proliferation
- Dihydrotestosterone/pharmacology
- Disease Progression
- Dose-Response Relationship, Drug
- Drug Resistance, Neoplasm
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Humans
- Male
- Phosphorylation
- Promoter Regions, Genetic
- Prostatic Neoplasms, Castration-Resistant/drug therapy
- Prostatic Neoplasms, Castration-Resistant/enzymology
- Prostatic Neoplasms, Castration-Resistant/genetics
- Prostatic Neoplasms, Castration-Resistant/pathology
- Receptors, Androgen/drug effects
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Signal Transduction
- Time Factors
- Transcription, Genetic/drug effects
- Transcriptome
- Transfection
- src-Family Kinases/genetics
- src-Family Kinases/metabolism
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Affiliation(s)
- Indranil Chattopadhyay
- Department of Life Sciences, School of Basic and Applied Science, Central University of Tamil Nadu, Thiruvarur, Tamil Nadu, India
| | - Jianmin Wang
- Department of Bioinformatics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - Maochun Qin
- Department of Bioinformatics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - Lingqiu Gao
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | - Renae Holtz
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
| | | | - Robert W. Leach
- Lewis-Sigler Institute for Integrative Genomics, Princeton, NJ, USA
| | - Irwin H. Gelman
- Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, NY, USA
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11
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Vazquez-Mellado MJ, Monjaras-Embriz V, Rocha-Zavaleta L. Erythropoietin, Stem Cell Factor, and Cancer Cell Migration. VITAMINS AND HORMONES 2017. [DOI: 10.1016/bs.vh.2017.02.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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12
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Abbaspour Babaei M, Kamalidehghan B, Saleem M, Huri HZ, Ahmadipour F. Receptor tyrosine kinase (c-Kit) inhibitors: a potential therapeutic target in cancer cells. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:2443-59. [PMID: 27536065 PMCID: PMC4975146 DOI: 10.2147/dddt.s89114] [Citation(s) in RCA: 172] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
c-Kit, a receptor tyrosine kinase, is involved in intracellular signaling, and the mutated form of c-Kit plays a crucial role in occurrence of some cancers. The function of c-Kit has led to the concept that inhibiting c-Kit kinase activity can be a target for cancer therapy. The promising results of inhibition of c-Kit for treatment of cancers have been observed in some cancers such as gastrointestinal stromal tumor, acute myeloid leukemia, melanoma, and other tumors, and these results have encouraged attempts toward improvement of using c-Kit as a capable target for cancer therapy. This paper presents the findings of previous studies regarding c-Kit as a receptor tyrosine kinase and an oncogene, as well as its gene targets and signaling pathways in normal and cancer cells. The c-Kit gene location, protein structure, and the role of c-Kit in normal cell have been discussed. Comprehending the molecular mechanism underlying c-Kit-mediated tumorogenesis is consequently essential and may lead to the identification of future novel drug targets. The potential mechanisms by which c-Kit induces cellular transformation have been described. This study aims to elucidate the function of c-Kit for future cancer therapy. In addition, it has c-Kit inhibitor drug properties and their functions have been listed in tables and demonstrated in schematic pictures. This review also has collected previous studies that targeted c-Kit as a novel strategy for cancer therapy. This paper further emphasizes the advantages of this approach, as well as the limitations that must be addressed in the future. Finally, although c-Kit is an attractive target for cancer therapy, based on the outcomes of treatment of patients with c-Kit inhibitors, it is unlikely that Kit inhibitors alone can lead to cure. It seems that c-Kit mutations alone are not sufficient for tumorogenesis, but do play a crucial role in cancer occurrence.
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Affiliation(s)
| | - Behnam Kamalidehghan
- Department of Medical Genetics, National Institute of Genetic Engineering and Biotechnology (NIGEB), Shahrak-e Pajoohesh; Medical Genetics Department, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Saleem
- Department of Urology; Department of Laboratory Medicine and Pathology, Masonic Cancer Center, University of Minnesota; Section of Molecular Therapeutics & Cancer Health Disparity, The Hormel Institute, Austin, MN, USA
| | - Hasniza Zaman Huri
- Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; Clinical Investigation Centre, University Malaya Medical Centre, Lembah Pantai, Kuala Lumpur, Malaysia
| | - Fatemeh Ahmadipour
- Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
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13
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Figueira MI, Correia S, Vaz CV, Cardoso HJ, Gomes IM, Marques R, Maia CJ, Socorro S. Estrogens down-regulate the stem cell factor (SCF)/c-KIT system in prostate cells: Evidence of antiproliferative and proapoptotic effects. Biochem Pharmacol 2015; 99:73-87. [PMID: 26592659 DOI: 10.1016/j.bcp.2015.11.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Accepted: 11/13/2015] [Indexed: 10/22/2022]
Abstract
The development of prostate cancer (PCa) is intimately associated with the hormonal environment, and the sex steroids estrogens have been implicated in prostate malignancy. However, if some studies identified estrogens as causative agents of PCa, others indicated that these steroids have a protective role counteracting prostate overgrowth. The tyrosine kinase receptor c-KIT and its ligand, the stem cell factor (SCF), have been associated with the control of cell proliferation/apoptosis and prostate carcinogenesis, and studies show that estrogens regulate their expression in different tissues, though, in the case of prostate this remains unknown. The present study aims to evaluate the role of 17β-estradiol (E2) in regulating the expression of SCF/c-KIT in human prostate cell lines and rat prostate, and to investigate the consequent effects on prostate cell proliferation and apoptosis. qPCR, Western Blot, and immuno(cito)histochemistry analysis showed that E2-treatment decreased the expression of SCF and c-KIT both in human prostate cells and rat prostate. Furthermore, the diminished expression of SCF/c-KIT was underpinned by the diminished prostate weight and reduced proliferation index. On the other hand, the results of TUNEL labelling, the increased activity of caspase-3, and the augmented expression of caspase-8 and Fas system in the prostate of E2-treated animals indicated augmented apoptosis in response to E2. The obtained results demonstrated that E2 down-regulated the expression of SCF/c-KIT system in prostate cells, which was associated with antiproliferative and proapoptotic effects. Moreover, these findings support the protective role of estrogens in PCa and open new perspectives on the application of estrogen-based therapies.
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Affiliation(s)
- Marília I Figueira
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Sara Correia
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Cátia V Vaz
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Henrique J Cardoso
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Inês M Gomes
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Ricardo Marques
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Cláudio J Maia
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Sílvia Socorro
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal.
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14
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Stockley J, Markert E, Zhou Y, Robson CN, Elliott DJ, Lindberg J, Leung HY, Rajan P. The RNA-binding protein Sam68 regulates expression and transcription function of the androgen receptor splice variant AR-V7. Sci Rep 2015; 5:13426. [PMID: 26310125 PMCID: PMC4550848 DOI: 10.1038/srep13426] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 07/27/2015] [Indexed: 12/02/2022] Open
Abstract
Castration-resistant (CR) prostate cancer (PCa) partly arises due to persistence of androgen receptor (AR) transcriptional activity in the absence of cognate ligand. An emerging mechanism underlying the CRPCa phenotype and predicting response to therapy is the expression of the constitutively-active AR-V7 splice variant generated by AR cryptic exon 3b inclusion. Here, we explore the role of the RNA-binding protein (RBP) Sam68 (encoded by KHDRBS1), which is over-expressed in clinical PCa, on AR-V7 expression and transcription function. Using a minigene reporter, we show that Sam68 controls expression of exon 3b resulting in an increase in endogenous AR-V7 mRNA and protein expression in RNA-binding-dependent manner. We identify a novel protein-protein interaction between Sam68 and AR-V7 mediated by a common domain shared with full-length AR, and observe these proteins in the cell nucleoplasm. Using a luciferase reporter, we demonstrate that Sam68 co-activates ligand-independent AR-V7 transcriptional activity in an RNA-binding-independent manner, and controls expression of the endogenous AR-V7-specific gene target UBE2C. Our data suggest that Sam68 has separable effects on the regulation of AR-V7 expression and transcriptional activity, through its RNA-binding capacity. Sam68 and other RBPs may control expression of AR-V7 and other splice variants as well as their downstream functions in CRPCa.
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MESH Headings
- Adaptor Proteins, Signal Transducing/genetics
- Adaptor Proteins, Signal Transducing/metabolism
- Alternative Splicing/genetics
- Cell Line, Tumor
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Exons/genetics
- Gene Expression Regulation, Neoplastic
- HEK293 Cells
- Humans
- Male
- Models, Biological
- Prostatic Neoplasms/genetics
- Protein Binding
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Receptors, Androgen/chemistry
- Receptors, Androgen/genetics
- Transcription, Genetic
- Ubiquitin-Conjugating Enzymes/genetics
- Ubiquitin-Conjugating Enzymes/metabolism
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Affiliation(s)
| | - Elke Markert
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | - Yan Zhou
- Cancer Research UK Beatson Institute, Glasgow, UK
| | - Craig N. Robson
- Northern Institute for Cancer Research, Newcastle University, Newcastle-upon-Tyne, UK
| | - David J. Elliott
- Institute of Genetic Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Johan Lindberg
- Department of Molecular Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
| | - Hing Y. Leung
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
- Cancer Research UK Beatson Institute, Glasgow, UK
| | - Prabhakar Rajan
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
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15
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SAM68: Signal Transduction and RNA Metabolism in Human Cancer. BIOMED RESEARCH INTERNATIONAL 2015; 2015:528954. [PMID: 26273626 PMCID: PMC4529925 DOI: 10.1155/2015/528954] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 02/24/2015] [Indexed: 12/21/2022]
Abstract
Alterations in expression and/or activity of splicing factors as well as mutations in cis-acting
splicing regulatory sequences contribute to cancer phenotypes. Genome-wide
studies have revealed more than 15,000 tumor-associated splice variants derived from
genes involved in almost every aspect of cancer cell biology, including proliferation,
differentiation, cell cycle control, metabolism, apoptosis, motility, invasion, and
angiogenesis. In the past decades, several RNA binding proteins (RBPs) have been
implicated in tumorigenesis. SAM68 (SRC associated in mitosis of 68 kDa) belongs to
the STAR (signal transduction and activation of RNA metabolism) family of RBPs.
SAM68 is involved in several steps of mRNA metabolism, from transcription to
alternative splicing and then to nuclear export. Moreover, SAM68 participates in signaling
pathways associated with cell response to stimuli, cell cycle transitions, and viral
infections. Recent evidence has linked this RBP to the onset and progression of
different tumors, highlighting misregulation of SAM68-regulated splicing events as a
key step in neoplastic transformation and tumor progression. Here we review recent
studies on the role of SAM68 in splicing regulation and we discuss its contribution to
aberrant pre-mRNA processing in cancer.
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16
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Cardoso HJ, Vaz CV, Correia S, Figueira MI, Marques R, Maia CJ, Socorro S. Paradoxical and contradictory effects of imatinib in two cell line models of hormone-refractory prostate cancer. Prostate 2015; 75:923-35. [PMID: 25786656 DOI: 10.1002/pros.22976] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 01/13/2015] [Indexed: 01/26/2023]
Abstract
BACKGROUND Imatinib mesylate is a chemotherapeutic drug that inhibits the tyrosine kinase activity of c-KIT and has been successfully used to treat leukemias and some solid tumors. However, its application for treatment of hormone-refractory prostate cancer (HRPC) has shown modest effectiveness and did not follow the outcomes in cultured cells or animal models. Moreover, the molecular pathways by which imatinib induces cytotoxicity in prostate cancer cells are poorly characterized. METHODS Two cell line models of HRPC (DU145 and PC3) were exposed to 20 μM of imatinib for 6-72 hr. MTS assay was used to assess cell viability during the course of experiment. Gene expression analysis of c-KIT, cell-cycle and apoptosis regulators, and angiogenic factors was determined by means of real-time PCR, western blot, and/or immunocytochemistry. The enzymatic activity of the apoptosis effector, caspase-3, was determined by a colorimetric assay. RESULTS Imatinib significantly decreased the viability of DU145 cells but paradoxically augmented the viability of PC3 cells. DU145 cells displayed diminished expression of anti-apoptotic Bcl-2 protein and augmented levels of caspase-8 and -9, as well as, increased enzymatic activity of caspase-3 in response to imatinib. No differences existed on the expression levels of apoptosis-related proteins in PC3 cells treated with imatinib, though the activity of caspase-3 was decreased. The mRNA levels of angiogenic factor VEGF were decreased in DU145-treated cells, whereas an opposite effect was seen in PC3. In addition, it was shown that DU145 and PC3 cells present a differential expression of c-KIT protein variants. CONCLUSION DU145 and PC3 cells displayed a contradictory behavior in response to imatinib, which was underpinned by a distinct expression pattern (or activity) of target regulators of cell-cycle, apoptosis, and angiogenesis. The paradoxical effect of imatinib in PC3 cells may be related with the differential expression of c-KIT protein variants. Moreover, the present findings helped to understand the discrepancies in the efficacy of imatinib as therapeutic option in HRPC.
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Affiliation(s)
- Henrique J Cardoso
- CICS-UBI, Health Sciences Research Center, University of Beira Interior, Covilhã, Portugal
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17
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Cardoso HJ, Figueira MI, Correia S, Vaz CV, Socorro S. The SCF/c-KIT system in the male: Survival strategies in fertility and cancer. Mol Reprod Dev 2014; 81:1064-79. [PMID: 25359157 DOI: 10.1002/mrd.22430] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 09/25/2014] [Indexed: 12/18/2022]
Abstract
Maintaining the delicate balance between cell survival and death is of the utmost importance for the proper development of germ cells and subsequent fertility. On the other hand, the fine regulation of tissue homeostasis by mechanisms that control cell fate is a factor that can prevent carcinogenesis. c-KIT is a type III receptor tyrosine kinase activated by its ligand, stem cell factor (SCF). c-KIT signaling plays a crucial role in cell fate decisions, specifically controlling cell proliferation, differentiation, survival, and apoptosis. Indeed, deregulating the SCF/c-KIT system by attenuation or overactivation of its signaling strength is linked to male infertility and cancer, and rebalancing its activity via c-KIT inhibitors has proven beneficial in treating human tumors that contain gain-of-function mutations or overexpress c-KIT. This review addresses the roles of SCF and c-KIT in the male reproductive tract, and discusses the potential application of c-KIT target therapies in disorders of the reproductive system.
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Affiliation(s)
- Henrique J Cardoso
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
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18
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Gelman IH. Androgen receptor activation in castration-recurrent prostate cancer: the role of Src-family and Ack1 tyrosine kinases. Int J Biol Sci 2014; 10:620-6. [PMID: 24948875 PMCID: PMC4062955 DOI: 10.7150/ijbs.8264] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 01/06/2014] [Indexed: 11/13/2022] Open
Abstract
There is growing appreciation that castration-recurrent prostate cancer (CR-CaP) is driven by the continued expression of androgen receptor (AR). AR activation in CR-CaP through various mechanisms, including AR overexpression, expression of AR splice variants or mutants, increased expression of co-regulator proteins, and by post-translational modification, allows for the induction of AR-regulated genes in response to very low levels of tissue-expressed, so-called intracrine androgens, resulting in pathways that mediate CaP proliferation, anti-apoptosis and oncogenic aggressiveness. The current review focuses on the role played by Src-family (SFK) and Ack1 non-receptor tyrosine kinases in activating AR through direct phosphorylation, respectively, on tyrosines 534 or 267, and how these modifications facilitate progression to CR-CaP. The fact that SFK and Ack1 are central mediators for multiple growth factor receptor signaling pathways that become activated in CR-CaP, especially in the context of metastatic growth in the bone, has contributed to recent therapeutic trials using SFK/Ack1 inhibitors in monotherapy or in combination with antagonists of the AR activation axis.
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Affiliation(s)
- Irwin H. Gelman
- Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
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19
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Unlocking Doors without Keys: Activation of Src by Truncated C-terminal Intracellular Receptor Tyrosine Kinases Lacking Tyrosine Kinase Activity. Cells 2014; 3:92-111. [PMID: 24709904 PMCID: PMC3980740 DOI: 10.3390/cells3010092] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 02/07/2014] [Accepted: 02/07/2014] [Indexed: 01/07/2023] Open
Abstract
One of the best examples of the renaissance of Src as an open door to cancer has been the demonstration that just five min of Src activation is sufficient for transformation and also for induction and maintenance of cancer stem cells [1]. Many tyrosine kinase receptors, through the binding of their ligands, become the keys that unlock the structure of Src and activate its oncogenic transduction pathways. Furthermore, intracellular isoforms of these receptors, devoid of any tyrosine kinase activity, still retain the ability to unlock Src. This has been shown with a truncated isoform of KIT (tr-KIT) and a truncated isoform of VEGFR-1 (i21-VEGFR-1), which are intracellular and require no ligand binding, but are nonetheless able to activate Src and induce cell migration and invasion of cancer cells. Expression of the i21-VEGFR-1 is upregulated by the Notch signaling pathway and repressed by miR-200c and retinoic acid in breast cancer cells. Both Notch inhibitors and retinoic acid have been proposed as potential therapies for invasive breast cancer.
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20
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Sánchez-Jiménez F, Sánchez-Margalet V. Role of Sam68 in post-transcriptional gene regulation. Int J Mol Sci 2013; 14:23402-19. [PMID: 24287914 PMCID: PMC3876053 DOI: 10.3390/ijms141223402] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 11/11/2013] [Accepted: 11/13/2013] [Indexed: 01/10/2023] Open
Abstract
The STAR family of proteins links signaling pathways to various aspects of post-transcriptional regulation and processing of RNAs. Sam68 belongs to this class of heteronuclear ribonucleoprotein particle K (hnRNP K) homology (KH) single domain-containing family of RNA-binding proteins that also contains some domains predicted to bind critical components in signal transduction pathways. In response to phosphorylation and other post-transcriptional modifications, Sam68 has been shown to have the ability to link signal transduction pathways to downstream effects regulating RNA metabolism, including transcription, alternative splicing or RNA transport. In addition to its function as a docking protein in some signaling pathways, this prototypic STAR protein has been identified to have a nuclear localization and to take part in the formation of both nuclear and cytosolic multi-molecular complexes such as Sam68 nuclear bodies and stress granules. Coupling with other proteins and RNA targets, Sam68 may play a role in the regulation of differential expression and mRNA processing and translation according to internal and external signals, thus mediating important physiological functions, such as cell death, proliferation or cell differentiation.
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Affiliation(s)
- Flora Sánchez-Jiménez
- Department of Medical Biochemistry and Molecular Biology and Immunology, UGC Clinical Biochemistry, Virgen Macarena University Hospital, Avenue. Sánchez Pizjuan 4, Medical School, University of Seville, Seville 41009, Spain.
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21
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Sette C. Alternative splicing programs in prostate cancer. Int J Cell Biol 2013; 2013:458727. [PMID: 23983695 PMCID: PMC3747374 DOI: 10.1155/2013/458727] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 07/11/2013] [Indexed: 12/31/2022] Open
Abstract
Prostate cancer (PCa) remains one of the most frequent causes of death for cancer in the male population. Although the initial antiandrogenic therapies are efficacious, PCa often evolves into a hormone-resistant, incurable disease. The genetic and phenotypic heterogeneity of this type of cancer renders its diagnosis and cure particularly challenging. Mounting evidence indicates that alternative splicing, the process that allows production of multiple mRNA variants from each gene, contributes to the heterogeneity of the disease. Key genes for the biology of normal and neoplastic prostate cells, such as those encoding for the androgen receptor and cyclin D1, are alternatively spliced to yield protein isoforms with different or even opposing functions. This review illustrates some examples of genes whose alternative splicing regulation is relevant to PCa biology and discusses the possibility to exploit alternative splicing regulation as a novel tool for prognosis, diagnosis, and therapeutic approaches to PCa.
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Affiliation(s)
- Claudio Sette
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata,” 00133 Rome, Italy
- Laboratory of Neuroembryology, Fondazione Santa Lucia IRCCS, 00143 Rome, Italy
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22
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Mazaris E, Tsiotras A. Molecular pathways in prostate cancer. Nephrourol Mon 2013; 5:792-800. [PMID: 24282788 PMCID: PMC3830904 DOI: 10.5812/numonthly.9430] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Accepted: 12/17/2012] [Indexed: 01/02/2023] Open
Abstract
Objectives Prostate cancer is a prevalent disease with a high impact on patients’ morbidity and mortality. Despite efforts to profile prostate cancer, the genetic alterations and biological processes that correlate with disease progression remain partially elusive. The purpose of this study is to review the recent evidence relating to the initiation and progression of prostate cancer in relation to the familial correlation of the disease, the genetic aberrations resulting in prostate cancer and the new molecular biology data regarding prostate cancer. Materials and Methods A Medline database search identified all the existing publications on the molecular events associated with the pathogenesis and evolution of prostate cancer. Particular emphasis was given on the specific genetic phenomena associated with prostate cancer. Results Like other cancers, prostate cancer is caused by an accumulation of genetic alterations in a cell that drives it to malignant growth. Specific genes and gene alterations have been suggested to play a role in its development and progression. Aneuploidy, loss of heterozygosity, gene mutations, hypermethylation and inactivation of specific tumour suppressor genes such as GSTpi, APC, MDR1, GPX3 and others have been detected in prostate cancers, but generally only at a low or moderate frequency. The androgen receptor (AR) signalling pathway may play a crucial role in the early development of prostate cancer, as well as in the development of androgen-independent disease that fails to respond to hormone deprivation therapies. Other alterations linked to the transition to hormone-independence include amplification of MYC and increased expression of ERBB2 and BCL2. Inflammatory changes may also contribute to the development of prostate cancer. Conclusion The identification of specific molecular markers for prostate cancer may lead to its earliest detection and better prediction of its behavior. The better understanding of the molecular events affecting prostate cancer progression may result in the introduction of new drugs to target these events thus providing a potential cure and a tool for prevention of this very common disease.
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Affiliation(s)
| | - Alexios Tsiotras
- Urology Department, Lister Hospital, Stevenage, United Kingdom
- Corresponding author: Alexios Tsiotras, Urology Department, Lister Hospital, Stevenage, United Kingdom. Tel: +44-7580348549, Fax: +44-1438515601, E-mail:
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23
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Ju X, Ertel A, Casimiro MC, Yu Z, Meng H, McCue PA, Walters R, Fortina P, Lisanti MP, Pestell RG. Novel oncogene-induced metastatic prostate cancer cell lines define human prostate cancer progression signatures. Cancer Res 2012. [PMID: 23204233 DOI: 10.1158/0008-5472.can-12-2133] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Herein, murine prostate cancer cell lines, generated via selective transduction with a single oncogene (c-Myc, Ha-Ras, and v-Src), showed oncogene-specific prostate cancer molecular signatures that were recapitulated in human prostate cancer and developed lung metastasis in immune-competent mice. Interrogation of two independent retrospective cohorts of patient samples using the oncogene signature showed an ability to distinguish tumor from normal prostate with a predictive value for prostate cancer of 98% to 99%. In a blinded study, the signature algorithm showed independent substratification of reduced recurrence-free survival by Kaplan-Meier analysis. The generation of new oncogene-specific prostate cancer cell lines that recapitulate human prostate cancer gene expression, which metastasize in immune-competent mice, are a valuable new resource for testing targeted therapy, whereas the molecular signatures identified herein provides further value over current gene signature markers of prediction and outcome.
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Affiliation(s)
- Xiaoming Ju
- Department of Cancer Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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24
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Lennartsson J, Rönnstrand L. Stem Cell Factor Receptor/c-Kit: From Basic Science to Clinical Implications. Physiol Rev 2012; 92:1619-49. [DOI: 10.1152/physrev.00046.2011] [Citation(s) in RCA: 485] [Impact Index Per Article: 40.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Stem cell factor (SCF) is a dimeric molecule that exerts its biological functions by binding to and activating the receptor tyrosine kinase c-Kit. Activation of c-Kit leads to its autophosphorylation and initiation of signal transduction. Signaling proteins are recruited to activated c-Kit by certain interaction domains (e.g., SH2 and PTB) that specifically bind to phosphorylated tyrosine residues in the intracellular region of c-Kit. Activation of c-Kit signaling has been found to mediate cell survival, migration, and proliferation depending on the cell type. Signaling from c-Kit is crucial for normal hematopoiesis, pigmentation, fertility, gut movement, and some aspects of the nervous system. Deregulated c-Kit kinase activity has been found in a number of pathological conditions, including cancer and allergy. The observation that gain-of-function mutations in c-Kit can promote tumor formation and progression has stimulated the development of therapeutics agents targeting this receptor, e.g., the clinically used inhibitor imatinib mesylate. Also other clinically used multiselective kinase inhibitors, for instance, sorafenib and sunitinib, have c-Kit included in their range of targets. Furthermore, loss-of-function mutations in c-Kit have been observed and shown to give rise to a condition called piebaldism. This review provides a summary of our current knowledge regarding structural and functional aspects of c-Kit signaling both under normal and pathological conditions, as well as advances in the development of low-molecular-weight molecules inhibiting c-Kit function.
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Affiliation(s)
- Johan Lennartsson
- Ludwig Institute for Cancer Research, Uppsala University, Uppsala, Sweden; and Experimental Clinical Chemistry, Wallenberg Laboratory, Department of Laboratory Medicine, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Lars Rönnstrand
- Ludwig Institute for Cancer Research, Uppsala University, Uppsala, Sweden; and Experimental Clinical Chemistry, Wallenberg Laboratory, Department of Laboratory Medicine, Lund University, Skåne University Hospital, Malmö, Sweden
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25
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Alternative splicing interference by xenobiotics. Toxicology 2012; 296:1-12. [DOI: 10.1016/j.tox.2012.01.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Revised: 01/21/2012] [Accepted: 01/23/2012] [Indexed: 12/21/2022]
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26
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Merkwitz C, Lochhead P, Tsikolia N, Koch D, Sygnecka K, Sakurai M, Spanel-Borowski K, Ricken AM. Expression of KIT in the ovary, and the role of somatic precursor cells. ACTA ACUST UNITED AC 2011; 46:131-84. [DOI: 10.1016/j.proghi.2011.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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27
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Abstract
Numerous studies
report splicing alterations in a multitude of
cancers by using gene-by-gene analysis. However,
understanding of the role of alternative
splicing in cancer is now reaching a new level,
thanks to the use of novel technologies allowing
the analysis of splicing at a large-scale level.
Genome-wide analyses of alternative splicing
indicate that splicing alterations can affect
the products of gene networks involved in key
cellular programs. In addition, many splicing
variants identified as being misregulated in
cancer are expressed in normal tissues. These
observations suggest that splicing programs
contribute to specific cellular programs that
are altered during cancer initiation and
progression. Supporting this model, recent
studies have identified splicing factors
controlling cancer-associated splicing programs.
The characterization of splicing programs and
their regulation by splicing factors will allow
a better understanding of the genetic mechanisms
involved in cancer initiation and progression
and the development of new therapeutic
targets.
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28
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Di Florio A, Adesso L, Pedrotti S, Capurso G, Pilozzi E, Corbo V, Scarpa A, Geremia R, Delle Fave G, Sette C. Src kinase activity coordinates cell adhesion and spreading with activation of mammalian target of rapamycin in pancreatic endocrine tumour cells. Endocr Relat Cancer 2011; 18:541-54. [PMID: 21712346 DOI: 10.1530/erc-10-0153] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Pancreatic endocrine tumours (PETs) are rare and heterogeneous neoplasms, often diagnosed at metastatic stage, for which no cure is currently available. Recently, activation of two pathways that support proliferation and invasiveness of cancer cells, the Src family kinase (SFK) and mammalian target of rapamycin (mTOR) pathways, was demonstrated in PETs. Since both pathways represent suitable targets for therapeutic intervention, we investigated their possible interaction in PETs. Western blot and immunofluorescence analyses indicated that SFK and mTOR activity correlate in PET cell lines. We also found that SFKs coordinate cell adhesion and spreading with activation of the mTOR pathway in PET cells. Live cell metabolic labelling and biochemical studies demonstrated that SFK activity enhance mTOR-dependent translation initiation. Furthermore, microarray analysis of the mRNAs associated with polyribosomes revealed that SFKs regulate mTOR-dependent translation of specific transcripts, with an enrichment in mRNAs encoding cell cycle proteins. Importantly, a synergic inhibition of proliferation was observed in PET cells concomitantly treated with SFK and mTOR inhibitors, without activation of the phosphatidylinositol 3-kinase/AKT pro-survival pathway. Tissue microarray analysis revealed activation of Src and mTOR in some PET samples, and identified phosphorylation of 4E-BP1 as an independent marker of poor prognosis in PETs. Thus, our work highlights a novel link between the SFK and mTOR pathways, which regulate the translation of mRNAs for cell cycle regulators, and suggest that crosstalk between these pathways promotes PET cell proliferation.
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Affiliation(s)
- Alessia Di Florio
- Department of Public Health and Cell Biology, University of Rome Tor Vergata, Italy
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29
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Rulina AV, Spirin PV, Prassolov VS. Activated leukemic oncogenes AML1-ETO and c-kit: role in development of acute myeloid leukemia and current approaches for their inhibition. BIOCHEMISTRY (MOSCOW) 2011; 75:1650-66. [PMID: 21417999 DOI: 10.1134/s0006297910130092] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Acute myeloid leukemia (AML) is a malignant blood disease caused by different mutations that enhance the proliferative activity and survival of blood cells and affect their differentiation and apoptosis. The most frequent disorders in AML are translocations between chromosomes 21 and 8 leading to production of a chimeric oncogene, AML1-ETO, and hyperexpression of the receptor tyrosine kinase KIT. Mutations in these genes often occur jointly. The presence in cells of two activated oncogenes is likely to trigger their malignization. The current approaches for treatment of oncologic diseases (bone marrow transplantation, radiotherapy, and chemotherapy) have significant shortcomings, and thus many laboratories are intensively developing new approaches against leukemias. Inhibiting expression of activated leukemic oncogenes based on the principle of RNA interference seems to be a promising approach in this field.
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Affiliation(s)
- A V Rulina
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.
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Bielli P, Busà R, Paronetto MP, Sette C. The RNA-binding protein Sam68 is a multifunctional player in human cancer. Endocr Relat Cancer 2011; 18:R91-R102. [PMID: 21565971 DOI: 10.1530/erc-11-0041] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Src associated in mitosis, of 68 kDa (Sam68) is a KH domain RNA-binding protein that belongs to the signal transduction and activation of RNA family. Although ubiquitously expressed, Sam68 plays very specialized roles in different cellular environments. In most cells, Sam68 resides in the nucleus and is involved in several steps of mRNA processing, from transcription, to alternative splicing, to nuclear export. In addition, Sam68 translocates to the cytoplasm upon cell stimulation, cell cycle transitions or viral infections, where it takes part to signaling complexes and associates with the mRNA translation machinery. Recent evidence has linked Sam68 function to the onset and progression of endocrine tumors, such as prostate and breast carcinomas. Notably, all the biochemical activities reported for Sam68 seem to be implicated in carcinogenesis. Herein, we review the recent advancement in the knowledge of Sam68 function and regulation and discuss it in the frame of its participation to neoplastic transformation and tumor progression.
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Affiliation(s)
- Pamela Bielli
- Department of Public Health and Cell Biology, University of Rome Tor Vergata, Italy
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31
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Martens-Uzunova ES, Jalava SE, Dits NF, van Leenders GJLH, Møller S, Trapman J, Bangma CH, Litman T, Visakorpi T, Jenster G. Diagnostic and prognostic signatures from the small non-coding RNA transcriptome in prostate cancer. Oncogene 2011; 31:978-91. [PMID: 21765474 DOI: 10.1038/onc.2011.304] [Citation(s) in RCA: 199] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Prostate cancer (PCa) is the most frequent male malignancy and the second most common cause of cancer-related death in Western countries. Current clinical and pathological methods are limited in the prediction of postoperative outcome. It is becoming increasingly evident that small non-coding RNA (ncRNA) species are associated with the development and progression of this malignancy. To assess the diversity and abundance of small ncRNAs in PCa, we analyzed the composition of the entire small transcriptome by Illumina/Solexa deep sequencing. We further analyzed the microRNA (miRNA) expression signatures of 102 fresh-frozen patient samples during PCa progression by miRNA microarrays. Both platforms were cross-validated by quantitative reverse transcriptase-PCR. Besides the altered expression of several miRNAs, our deep sequencing analyses revealed strong differential expression of small nucleolar RNAs (snoRNAs) and transfer RNAs (tRNAs). From microarray analysis, we derived a miRNA diagnostic classifier that accurately distinguishes normal from cancer samples. Furthermore, we were able to construct a PCa prognostic predictor that independently forecasts postoperative outcome. Importantly, the majority of miRNAs included in the predictor also exhibit high sequence counts and concordant differential expression in Illumina PCa samples, supported by quantitative reverse transcriptase-PCR. Our findings provide miRNA expression signatures that may serve as an accurate tool for the diagnosis and prognosis of PCa.
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Affiliation(s)
- E S Martens-Uzunova
- Department of Urology, Josephine Nefkens Institute, Erasmus MC, Rotterdam, The Netherlands
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32
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Jin JK, Dayyani F, Gallick GE. Steps in prostate cancer progression that lead to bone metastasis. Int J Cancer 2011; 128:2545-61. [PMID: 21365645 PMCID: PMC3082284 DOI: 10.1002/ijc.26024] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 01/28/2011] [Indexed: 12/14/2022]
Abstract
Prostate cancer is a complex disease in which metastasis to the bone is the main cause of death. Initial stages of metastasis are generally similar to those for most solid tumors; however, the mechanisms that underlie the homing of prostate tumor cells to the bone are not completely understood. Prostate cancer bone metastasis is also a microenvironment-driven disease, involving bidirectional interactions between the tumor and the bone microenvironment. In this review, we discuss the current understanding of the biologic processes and regulatory factors involved in the metastasis of prostate cancer cells, and their specific properties that promote growth in bone. Although many of these processes still need to be fully elucidated, a better understanding of the complex tumor/microenvironment interplay is slowly leading to more effective therapies for patients with prostate cancer bone metastases.
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Affiliation(s)
- Jung-Kang Jin
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX
| | - Farshid Dayyani
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Gary E. Gallick
- Department of Genitourinary Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
- The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX
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Abstract
Tyrosine kinases play significant roles in tumor progression and therapy resistance. Inhibitors of tyrosine kinases are on the forefront of targeted therapy. For prostate cancer, tyrosine kinases play an additional role in the development of castration-resistant disease state, the most troubling aspect of prostate cancinogenesis which presently defies any effective treatment. Among the 30 or so tyrosine kinases expressed in a typical prostate cancer cell, nearly one third of them have been implicated in prostate carcinogenesis. Interestingly, most of them channel signals through a trio of non-receptor tyrosine kinases, Src/Etk/FAK, referred here as Src tyrosine kinase complex. This complex has been shown to play a significant role in the aberrant activation of androgen receptor (AR) mediated by growth factors (e.g., epidermal growth factor (EGF)), cytokines (interleukin (IL)-6), chemokines (IL-8), and neurokines (gastrin-releasing peptide). These factors are induced and released from the prostate cancer to the stromal cells upon androgen withdrawal. The Src kinase complex has the ability to phosphorylate androgen receptor, resulting in the nuclear translocation and stabilization of un-liganded androgen receptor. Indeed, tyrosine kinase inhibitors targeting Src can inhibit androgen-independent growth of prostate cancer cells in vitro and in preclinical xenograft model. While effective in inducing growth arrest and inhibiting metastasis of castration-resistant tumors, Src inhibitors rarely induce a significant level of apoptosis. This is also reflected by the general ineffectiveness of tyrosine kinase inhibitors as monotherapy in clinical trials. One of the underlying causes of apoptosis resistance is "autophagy," which is induced by tyrosine kinase inhibitors and by androgen withdrawal. Autophagy is a self-digesting process to regenerate energy by removal of long-lived proteins and retired organelles to provide a survival mechanism to cells encountering stresses. Excessive autophagy, sometimes, could lead to type II programmed cell death. We demonstrated that autophagy blockade sensitizes prostate cancer cells toward Src tyrosine kinase inhibitor. Thus, a combination therapy based on Src tyrosine kinase inhibitor and autophagy modulator deserves further attention as a potential treatment for relapsed prostate cancer.
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Affiliation(s)
- Hsing-Jien Kung
- UC Davis Cancer Center, UCDMC, Res III, Rm. 2400, 4645 2nd Avenue, Sacramento, CA 95817, USA.
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Valacca C, Bonomi S, Buratti E, Pedrotti S, Baralle FE, Sette C, Ghigna C, Biamonti G. Sam68 regulates EMT through alternative splicing-activated nonsense-mediated mRNA decay of the SF2/ASF proto-oncogene. ACTA ACUST UNITED AC 2010; 191:87-99. [PMID: 20876280 PMCID: PMC2953442 DOI: 10.1083/jcb.201001073] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Expression levels of SF2/ASF are controlled by Sam68 mediated activation of splicing-induced mRNA decay. Epithelial-to-mesenchymal transition (EMT) and its reversal (MET) are crucial cell plasticity programs that act during development and tumor metastasis. We have previously shown that the splicing factor and proto-oncogene SF2/ASF impacts EMT/MET through production of a constitutively active splice variant of the Ron proto-oncogene. Using an in vitro model, we now show that SF2/ASF is also regulated during EMT/MET by alternative splicing associated with the nonsense-mediated mRNA decay pathway (AS-NMD). Overexpression and small interfering RNA experiments implicate the splicing regulator Sam68 in AS-NMD of SF2/ASF transcripts and in the choice between EMT/MET programs. Moreover, Sam68 modulation of SF2/ASF splicing appears to be controlled by epithelial cell–derived soluble factors that act through the ERK1/2 signaling pathway to regulate Sam68 phosphorylation. Collectively, our results reveal a hierarchy of splicing factors that integrate splicing decisions into EMT/MET programs in response to extracellular stimuli.
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Affiliation(s)
- Cristina Valacca
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), 27100 Pavia, Italy
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35
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Mezquita B, Mezquita J, Pau M, Mezquita C. A novel intracellular isoform of VEGFR-1 activates Src and promotes cell invasion in MDA-MB-231 breast cancer cells. J Cell Biochem 2010; 110:732-42. [PMID: 20512933 DOI: 10.1002/jcb.22584] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Two types of VEGFR-1 receptors have been characterized: a full-length transmembrane receptor and a truncated extracellular soluble isoform (sVEGFR-1). We report here the characterization, in normal and cancer cells, of a new family of intracellular isoforms of VEGFR-1 resulting from alternative initiation of transcription in intronic sequences of the gene. While the classical isoforms of VEGFR-1 were barely detectable in MDA-MB-231 breast cancer cells, one of the intracellular isoforms transcribed from intron 21 (i(21)VEGFR-1) was the main isoform expressed in these cells. The new transcript encodes for a protein that contains only the phosphotransferase domain and the carboxyterminal tail of VEGFR-1. Treatment of MDA-MB-231 cells with siRNA specific for the tyrosine domain of VEGFR-1 suppressed the expression of i(21)VEGFR-1, downregulated phosphorylation of Src at tyrosine 418, and reduced markedly the invasion capacity of these cells in vitro. Accordingly, overexpression of transfected i(21)VEGFR-1 in MDA-MB-231 cells upregulated the active form of Src and increased invasiveness of MDA-MB-231 cells. The expression of i(21)VEGFR-1 in MDA-MB-231 cells was inhibited by retinoic acid. Both, activation of Src and downregulation by retinoic acid, have been reported in other intracellular members of the Fms/Kit/PDGFR family of tyrosine kinases, particularly in the intracellular isoform of c-kit, analogous structurally to i(21)VEGFR-1 and frequently expressed in cancer cells.
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Affiliation(s)
- Belén Mezquita
- Laboratori de Genètica Molecular, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
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36
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Muciaccia B, Sette C, Paronetto MP, Barchi M, Pensini S, D'Agostino A, Gandini L, Geremia R, Stefanini M, Rossi P. Expression of a truncated form of KIT tyrosine kinase in human spermatozoa correlates with sperm DNA integrity. Hum Reprod 2010; 25:2188-202. [DOI: 10.1093/humrep/deq168] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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37
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Busà R, Sette C. An emerging role for nuclear RNA-mediated responses to genotoxic stress. RNA Biol 2010; 7:390-6. [PMID: 20639695 DOI: 10.4161/rna.7.4.12466] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Defects in the regulation of alternative splicing have strong relevance in the onset and progression of several types of human cancer. Modulation of alternative splicing allows cancer cells to adapt to hostile environments through production of specific mRNA variants. In particular, genotoxic stress exerted by chemotherapeutic drugs or irradiation strongly affects splicing of many genes. A key role in this aberrant regulation is played by the unbalanced expression of several splicing factors in cancer cells. Among them, the RNA-binding protein Sam68, which is overexpressed in various tumors, was shown to accumulate in nuclear foci of active transcription, together with other splicing regulators, and to affect splicing of target mRNAs in response to genotoxic stress. We suggest that subcellular redistribution of splicing factors is guided by changes in chromatin conformation elicited by DNA-damaging drugs. This event might represent an escape mechanism used by cancer cells to survive to genotoxic insults through expression of pro-survival, cancer-specific gene products.
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Affiliation(s)
- Roberta Busà
- Department of Public Health and Cell Biology, University of Rome Tor Vergata, Rome, Italy
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38
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Sette C. Post-translational regulation of star proteins and effects on their biological functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 693:54-66. [PMID: 21189685 DOI: 10.1007/978-1-4419-7005-3_4] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
STAR (Signal Transduction and Activation of RNA) proteins owed their name to the presence in their structure ofa RNA-binding domain and several hallmarks of their involvement in signal transduction pathways. In many members of the family, the STAR RNA-binding domain (also named GSG, an acronym for GRP33/Sam68/ GLD-1) is flanked by regulatory regions containing proline-rich sequences, which serve as docking sites for proteins containing SH3 and WW domains and also a tyrosine-rich region at the C-terminus, which can mediateprotein-protein interactions with partners through SH2 domains. These regulatory regions contain consensus sequences for additional modifications, including serine/threonine phosphorylation, methylation, acetylation and sumoylation. Since their initial description, evidence has been gathered in different cell types and model organisms that STAR proteins can indeed integrate signals from external and internal cues with changes in transcription and processing of target RNAs. The most striking example of the high versatility of STAR proteins is provided by Sam68 (KHDRBS1), whose function, subcellular localization and affinity for RNA are strongly modulated by several signaling pathways through specific modifications. Moreover, the recent development of genetic knockout models has unveiled the physiological function of some STAR proteins, pointing to a crucial role of their post-translational modifications in the biological processes regulated by these RNA-binding proteins. This chapter offers an overview of the most updated literature on the regulation of STAR proteins by post-translational modifications and illustrates examples of how signal transduction pathways can modulate their activity and affect biological processes.
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Affiliation(s)
- Claudio Sette
- Department of Public Health and Cell Biology, University of Rome Tor Vergata, Via Montpellier, 1, 00133, Rome, Italy.
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39
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Alternative splicing modulates autoinhibition and SH3 accessibility in the Src kinase Fyn. Mol Cell Biol 2009; 29:6438-48. [PMID: 19805512 DOI: 10.1128/mcb.00398-09] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Src family kinases are central regulators of a large number of signaling pathways. To adapt to the idiosyncrasies of different cell types, these kinases may need a fine-tuning of their intrinsic molecular control mechanisms. Here, we describe on a molecular level how the Fyn kinase uses alternative splicing to adapt to different cellular environments. Using structural analysis, site-directed mutagenesis, and functional analysis, we show how the inclusion of either exon 7A or 7B affects the autoinhibition of Fyn and how this changes the SH3-dependent interaction and tyrosine phosphorylation of Sam68, with functional consequences for the Sam68-regulated survival of epithelial cells. Our results illustrate a novel mechanism of evolution that may contribute to the complexity of Src kinase regulation.
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40
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Koch D, Sakurai M, Hummitzsch K, Hermsdorf T, Erdmann S, Schwalbe S, Stolzenburg JU, Spanel-Borowski K, Ricken AM. KIT variants in bovine ovarian cells and corpus luteum. Growth Factors 2009; 27:100-13. [PMID: 19225962 DOI: 10.1080/08977190802707571] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We report the presence of KIT variants in granulosa and thecal cells of the follicle and endothelial and steroidogenic cells of the corpus luteum. Transcripts of both full-length splice variants, KIT and KITA, were ubiquitously detected in all cell types, in contrast to transcripts for truncated KIT. RT-PCR with exon-intron-specific primers suggested that KIT transcripts retained intron sequences. We used domain-specific KIT antibodies to identify truncated KIT proteins in cell conditioned media and lysates. These proteins represented soluble KIT and a so far disregarded intracellular KIT fragment, and were ubiquitously present. In contrast, glycosylated variants of full-length KIT were predominantly detected in thecal and endothelial cells. All KIT variants were encountered again in COS-7 cells transfected with a vector containing KITA. Phorbol 12-myristate-13-acetate treatment induced levels of truncated KITs, and this effect was repressed by the metalloproteinase inhibitor TAPI-1. Our findings show that ectodomain cleavage of full-length KIT generates an intracellular KIT. Our experiments suggest that replenishing full-length KIT differs among various ovarian cell types.
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Affiliation(s)
- Daniela Koch
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
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41
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Yang JC, Ok JH, Busby JE, Borowsky AD, Kung HJ, Evans CP. Aberrant activation of androgen receptor in a new neuropeptide-autocrine model of androgen-insensitive prostate cancer. Cancer Res 2009; 69:151-60. [PMID: 19117998 DOI: 10.1158/0008-5472.can-08-0442] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Treatment of advanced prostate cancer with androgen deprivation therapy inevitably renders the tumors castration-resistant and incurable. Under these conditions, neuroendocrine differentiation of prostate cancer (CaP) cells is often detected and neuropeptides released by these cells may facilitate the development of androgen independence. Exemplified by gastrin-releasing peptide (GRP), these neuropeptides transmit their signals through G protein-coupled receptors, which are often overexpressed in prostate cancer, and aberrantly activate androgen receptor (AR) in the absence of androgen. We developed an autocrine neuropeptide model by overexpressing GRP in LNCaP cells and the resultant cell line, LNCaP-GRP, exhibited androgen-independent growth with enhanced motility in vitro. When orthotopically implanted in castrated nude mice, LNCaP-GRP produced aggressive tumors, which express GRP, prostate-specific antigen, and nuclear-localized AR. Chromatin immunoprecipitation studies of LNCaP-GRP clones suggest that GRP activates and recruits AR to the cognate promoter in the absence of androgen. A Src family kinase (SFK) inhibitor, AZD0530, inhibits androgen-independent growth and migration of the GRP-expressing cell lines, and blocks the nuclear translocation of AR, indicating the involvement of SFK in the aberrant activation of AR and demonstrating the potential use of SFK inhibitor in the treatment of castration-resistant CaP. In vivo studies have shown that AZD0530 profoundly inhibits tumor metastasis in severe combined immunodeficient mice implanted with GRP-autocrine LNCaP cells. This xenograft model shows autocrine, neuropeptide- and Src kinase-mediated progression of androgen-independent CaP postcastration, and is potentially useful for testing novel therapeutic agents.
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Affiliation(s)
- Joy C Yang
- Department of Urology and Biological Chemistry, School of Medicine, University of California at Davis, Sacramento, CA 95817, USA
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42
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C-kit and its ligand stem cell factor: potential contribution to prostate cancer bone metastasis. Neoplasia 2009; 10:996-1003. [PMID: 18714401 DOI: 10.1593/neo.08618] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2008] [Revised: 06/16/2008] [Accepted: 06/17/2008] [Indexed: 11/18/2022] Open
Abstract
The tyrosine kinase receptor c-kit and its ligand stem cell factor (SCF) have not been explored in prostate cancer (PC) bone metastasis. Herein, we found that three human PC cell lines and bone marrow stromal cells express a membrane-bound SCF isoform and release a soluble SCF. Bone marrow stromal cells revealed strong expression of c-kit, whereas PC cells showed very low levels of the receptor or did not express it all. Using an experimental model of PC bone metastasis, we found that intraosseous bone tumors formed by otherwise c-kit-negative PC3 cells strongly expressed c-kit, as demonstrated using immunohistochemical and Western blot analyses. Subcutaneous PC3 tumors were, however, c-kit-negative. Both bone and subcutaneous PC3 tumors were positive for SCF. Immunohistochemical analysis of human specimens revealed that the expression frequency of c-kit in epithelial cells was of 5% in benign prostatic hyperplasia, 14% in primary PC, and 40% in PC bone metastases, suggesting an overall trend of increased c-kit expression in clinical PC progression. Stem cell factor expression frequency was more than 80% in all the cases. Our data suggest that the bone microenvironment up-regulates c-kit expression on PC cells, favoring their intraosseous expansion.
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Sonpavde G, Hutson TE, Berry WR, Boehm KA, Asmar L. Phase II Trial of Sunitinib for the Therapy of Progressive Metastatic Castration-Refractory Prostate Cancer After Previous Docetaxel Chemotherapy. Clin Genitourin Cancer 2008; 6:134-7. [DOI: 10.3816/cgc.2008.n.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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44
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Mijatovic T, De Nève N, Gailly P, Mathieu V, Haibe-Kains B, Bontempi G, Lapeira J, Decaestecker C, Facchini V, Kiss R. Nucleolus and c-Myc: potential targets of cardenolide-mediated antitumor activity. Mol Cancer Ther 2008; 7:1285-96. [DOI: 10.1158/1535-7163.mct-07-2241] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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45
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Park SI, Zhang J, Phillips KA, Araujo JC, Najjar AM, Volgin AY, Gelovani JG, Kim SJ, Wang Z, Gallick GE. Targeting SRC family kinases inhibits growth and lymph node metastases of prostate cancer in an orthotopic nude mouse model. Cancer Res 2008; 68:3323-33. [PMID: 18451159 DOI: 10.1158/0008-5472.can-07-2997] [Citation(s) in RCA: 184] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Aberrant expression and/or activity of members of the Src family of nonreceptor protein tyrosine kinases (SFK) are commonly observed in progressive stages of human tumors. In prostate cancer, two SFKs (Src and Lyn) have been specifically implicated in tumor growth and progression. However, there are no data in preclinical models demonstrating potential efficacy of Src inhibitors against prostate cancer growth and/or metastasis. In this study, we used the small molecule SFK/Abl kinase inhibitor dasatinib, currently in clinical trials for solid tumors, to examine in vitro and in vivo effects of inhibiting SFKs in prostate tumor cells. In vitro, dasatinib inhibits both Src and Lyn activity, resulting in decreased cellular proliferation, migration, and invasion. In orthotopic nude mouse models, dasatinib treatment effectively inhibits expression of activated SFKs, resulting in inhibition of both tumor growth and development of lymph node metastases in both androgen-sensitive and androgen-resistant tumors. In primary tumors, SFK inhibition leads to decreased cellular proliferation (determined by immunohistochemistry for proliferating cell nuclear antigen). In vitro, small interfering RNA (siRNA)-mediated inhibition of Lyn affects cellular proliferation; siRNA inhibition of Src affects primarily cellular migration. Therefore, we conclude that SFKs are promising therapeutic targets for treatment of human prostate cancer and that Src and Lyn activities affect different cellular functions required for prostate tumor growth and progression.
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Affiliation(s)
- Serk In Park
- The Program in Cancer Biology, Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, TX 77030, USA
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46
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Multiple oncogenic pathway signatures show coordinate expression patterns in human prostate tumors. PLoS One 2008; 3:e1816. [PMID: 18350153 PMCID: PMC2263127 DOI: 10.1371/journal.pone.0001816] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Accepted: 02/20/2008] [Indexed: 11/19/2022] Open
Abstract
Background Gene transcription patterns associated with activation of oncogenes Myc, c-Src, beta-catenin, E2F3, H-Ras, HER2, EGFR, MEK, Raf, MAPK, Akt, and cyclin D1, as well as of the cell cycle and of androgen signaling have been generated in previous studies using experimental models. It was not clear whether genes in these “oncogenic signatures” would show coordinate expression patterns in human prostate tumors, particularly as most of the signatures were derived from cell types other than prostate. Principal Findings The above oncogenic pathway signatures were examined in four different gene expression profile datasets of human prostate tumors (representing ∼250 patients in all), using both Q1-Q2 and one-sided Fisher's exact enrichment analysis methods. A significant fraction (∼5%) of genes up-regulated experimentally by Myc, c-Src, HER2, Akt, or androgen were co-expressed in human tumors with the oncogene or biomarker corresponding to the pathway signature. Genes down-regulated experimentally, however, did not show anticipated patterns of anti-enrichment in the human tumors. Conclusions Significant subsets of the genes in these experimentally-derived oncogenic signatures are relevant to the study of human prostate cancer. Both molecular biologists and clinical researchers could focus attention on the relatively small number of genes identified here as having coordinate patterns that arise from both the experimental system and the human disease system.
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47
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Lukong KE, Richard S. Targeting the RNA-binding protein Sam68 as a treatment for cancer? Future Oncol 2008; 3:539-44. [PMID: 17927519 DOI: 10.2217/14796694.3.5.539] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The contradictory properties of RNA-binding proteins (RBPs) have mystified their roles in human diseases including cancer. Are certain RBPs oncogenes or tumor suppressors? In the case of the signal transduction activator of RNA metabolism (STAR) family of hnRNP K homology (KH)-domain-containing RBPs, the dominant view with loose experimental evidence is that these proteins are tumor suppressors. However, recent developments support a pro-oncogenic role for archetypical STAR protein Sam68. Sam68-null mice are not prone to cancer, but instead display pronounced defects in mammary gland ductal development, and haploinsufficiency of Sam68 impedes mammary tumor onset and tumor multiplicity in mouse models expressing the mammary-targeted polyoma middle T antigen oncogene. These advances have increased the interest in the role of Sam68 as a positive regulator of cancer progression and position Sam68 as a viable therapeutic target. Retrospective and perspective implications of Sam68 in cancer are discussed.
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Affiliation(s)
- Kiven E Lukong
- Lady Davis Institute, 3755 Côte Ste.-Catherine Road, Montréal, Québec H3T 1E2, Canada.
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48
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Abstract
The Src family kinases (SFKs) are the largest family of nonreceptor protein tyrosine kinases and are responsible for signal transduction during many cellular activities, including differentiation, adhesion, and migration. Aberrant Src/SFK activity has been widely implicated in cancer development. Several lines of evidence indicate a role for SFKs in the development of prostate cancer, e.g. SFK overexpression in prostate cancer cell lines and tissues and reduced cancer cell proliferation, invasion, and migration following Src inhibition. In particular, Src may be involved in androgen-independent growth during advanced stages of disease. Src signaling is also a key pathway during normal and dysregulated bone functioning, and bone metastases are responsible for substantial morbidity in advanced prostate cancer. Src/SFK inhibition therefore represents a potentially useful therapeutic strategy for patients with various stages of prostate cancer. To date, four Src inhibitors have reached clinical trials. Of these, the broadest range of in vitro prostate cancer data are available for dasatinib, which inhibits several SFKs as well as other tyrosine kinases. Src inhibitors may be specifically evaluated in prostate cancer clinical trials in the near future.
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Affiliation(s)
- K Fizazi
- Department of Medicine, Institut Gustave-Roussy, 39 rue Camille Desmoulins, 94800 Villejuif, France.
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49
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Molderings GJ, Kolck UW, Scheurlen C, Brüss M, Homann J, Von Kügelgen I. Multiple novel alterations in Kit tyrosine kinase in patients with gastrointestinally pronounced systemic mast cell activation disorder. Scand J Gastroenterol 2007; 42:1045-53. [PMID: 17710669 DOI: 10.1080/00365520701245744] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Sequencing efforts to discover mutations in the tyrosine kinase Kit related to systemic mast cell disorders have so far been focused mainly on only a few of the 21 exons of the encoding gene c-kit, thus considerably limiting the possibility to quantitatively reveal pathogenetic relationships. The purpose of this study was to analyze and compare the total sequence of Kit tyrosine kinase at the level of the mRNAs obtained from patients with clear systemic signs of a pathologically increased mast cell mediator release and those from healthy volunteers. MATERIAL AND METHODS Kit encoding mRNA isolated from mast cell progenitors in peripheral blood from 17 patients with a mast cell activation disorder and from 5 healthy volunteers as well as from the human mast cell leukemia cell line HMC1 was analyzed for alterations. RESULTS Multiple novel point mutations and six isoforms of Kit which are due to alternative mRNA splicing were detected. One isoform, the insertion of a glutamine residue at amino acid position 252, was found to be a new splice variant expressed in all patients but in none of the healthy volunteers. CONCLUSIONS Systemic mast cell activation disorder was pathogenetically characterized by two or more alterations in the Kit tyrosine kinase providing not only a means of confirming the diagnosis, but also of assessing prognosis and of starting adequate therapeutic interventions. The insertion of Q252 appears to be pathognomic for that disease, providing a novel means for the identification of chronic non-specific gastrointestinal symptoms as manifestations of a systemic mast cell activation disorder.
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50
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Wang Y, Culty M. Identification and distribution of a novel platelet-derived growth factor receptor beta variant: effect of retinoic acid and involvement in cell differentiation. Endocrinology 2007; 148:2233-50. [PMID: 17303670 DOI: 10.1210/en.2006-1206] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
We have shown previously that neonatal testicular gonocytes express platelet-derived growth factor receptors (PDGFR) alpha and beta. We report the expression of a novel PDGFRbeta (V1-PDGFRbeta) transcript in gonocytes of 3-d-old rat testes. V1-PDGFRbeta nucleotide sequence spans from intron 6 to exon 23 of the PDGFRbeta gene, and is predicted to encode a protein lacking part of the extracellular domain. V1-PDGFRbeta transcripts are expressed preferentially in developing gonads. The embryonic teratocarcinoma F9 cells, in which differentiation is driven by retinoic acid (RA), express V1-PDGFRbeta, but not wild-type PDGFRbeta. Green fluorescent protein-tagged V1-PDGFRbeta localized mainly in cytosol of F9, MA-10, and COS-1 cells. FLAG and green fluorescent protein-tagged V1-PDGFRbeta displayed tyrosine kinase activities and contain phosphotyrosine residues, suggesting that V1-PDGFRbeta is a cytosolic tyrosine kinase. Treatment of F9 cells with RA induced V1-PDGFRbeta gene expression, concomitant with changes in morphology and increased mRNA expression of collagen IV and laminin B1, suggesting that V1-PFGRbeta is involved in cell differentiation. Similarly, treatment of postnatal d 3 rat gonocytes with RA induced a dose-dependent increase in V1-PDGFRbeta expression together with an increase in c-kit and Stra8, markers of more differentiated germ cells and a concomitant decrease in GFRalpha1, a marker of spermatogonial stem cells. However, an excess of V1-PDGFRbeta inhibited RA-mediated collagen IV and laminin B1 expression and altered both RA-dependent and RA-independent morphological changes in F9 cells, while increasing cell survival. These results suggest that the expression of V1-PDGFRbeta is tightly regulated during differentiation and that it may play an active role in germ cell differentiation.
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Affiliation(s)
- Yan Wang
- Department of Biochemistry and Molecular and Cellular Biology, Georgetown University Medical Center, Washington, D.C. 20057, USA
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