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1.
J Pathol ; 244(1): 11-24, 2018 01.
Article in English | MEDLINE | ID: mdl-28888037

ABSTRACT

Telomerase consists of at least two essential elements, an RNA component hTR or TERC that contains the template for telomere DNA addition and a catalytic reverse transcriptase (TERT). While expression of TERT has been considered the key rate-limiting component for telomerase activity, increasing evidence suggests an important role for the regulation of TERC in telomere maintenance and perhaps other functions in human cancer. By using three orthogonal methods including RNAseq, RT-qPCR, and an analytically validated chromogenic RNA in situ hybridization assay, we report consistent overexpression of TERC in prostate cancer. This overexpression occurs at the precursor stage (e.g. high-grade prostatic intraepithelial neoplasia or PIN) and persists throughout all stages of disease progression. Levels of TERC correlate with levels of MYC (a known driver of prostate cancer) in clinical samples and we also show the following: forced reductions of MYC result in decreased TERC levels in eight cancer cell lines (prostate, lung, breast, and colorectal); forced overexpression of MYC in PCa cell lines, and in the mouse prostate, results in increased TERC levels; human TERC promoter activity is decreased after MYC silencing; and MYC occupies the TERC locus as assessed by chromatin immunoprecipitation (ChIP). Finally, we show that knockdown of TERC by siRNA results in reduced proliferation of prostate cancer cell lines. These studies indicate that TERC is consistently overexpressed in all stages of prostatic adenocarcinoma and that its expression is regulated by MYC. These findings nominate TERC as a novel prostate cancer biomarker and therapeutic target. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Subject(s)
Gene Expression Regulation, Neoplastic , Prostatic Intraepithelial Neoplasia/genetics , Prostatic Neoplasms/genetics , Proto-Oncogene Proteins c-myc/genetics , RNA, Small Interfering/genetics , RNA/genetics , Telomerase/genetics , Adult , Aged , Animals , Cell Proliferation , Genes, Reporter , Humans , In Situ Hybridization , Male , Mice , Mice, Transgenic , Middle Aged , Prostate/pathology , Prostatic Intraepithelial Neoplasia/pathology , Prostatic Neoplasms/pathology , Sequence Analysis, RNA , Telomere/genetics
2.
Clin Cancer Res ; 14(12): 3699-705, 2008 Jun 15.
Article in English | MEDLINE | ID: mdl-18559586

ABSTRACT

The past several years have seen unprecedented advances in the application of various therapeutic strategies for the treatment of patients with renal cancer. The availability of active immunotherapy, antiangiogenic therapy, and targeted therapy for this disease has brought front and center issues related to choosing the appropriate treatment for particular patient populations. It is increasingly evident that the most promising treatment selection strategies will incorporate identifying specific features of the tumor itself. To facilitate this move toward personalized medicine, it is critically important to establish some standard principles for renal cancer tissue collection, preparation, and analysis for translational research studies. In this article, we identify and discuss some critical issues related to tissue-based kidney cancer research. We focus on five major areas as follows: (a) surgical and image-guided techniques for tissue collection; (b) quality control of specimen collection, processing, storage, and review; (c) issues related to analysis of paraffin embedded tissues; (d) genomic studies; and (e) assessment of reproducibility of assays across institutions. In addition, some practical implementation strategies are proposed. Although many of the topics discussed are specific for renal cancer, several are also relevant to tissue based biomarker investigations in a broad array of malignancies.


Subject(s)
Carcinoma, Renal Cell/pathology , Drug Evaluation, Preclinical/methods , Drug Evaluation, Preclinical/trends , Kidney Neoplasms/pathology , Tissue and Organ Harvesting/methods , Tissue and Organ Harvesting/trends , Algorithms , Biomarkers, Tumor/analysis , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/surgery , Genomics/methods , Humans , Kidney Neoplasms/genetics , Kidney Neoplasms/surgery , Models, Biological , Paraffin Embedding/methods , Quality Control , Research Design , Surgery, Computer-Assisted/methods , Tissue Banks
3.
Clin Cancer Res ; 25(23): 6916-6924, 2019 12 01.
Article in English | MEDLINE | ID: mdl-31363002

ABSTRACT

Lineage plasticity has emerged as an important mechanism of treatment resistance in prostate cancer. Treatment-refractory prostate cancers are increasingly associated with loss of luminal prostate markers, and in many cases induction of developmental programs, stem cell-like phenotypes, and neuroendocrine/neuronal features. Clinically, lineage plasticity may manifest as low PSA progression, resistance to androgen receptor (AR) pathway inhibitors, and sometimes small cell/neuroendocrine pathologic features observed on metastatic biopsy. This mechanism is not restricted to prostate cancer as other malignancies also demonstrate lineage plasticity during resistance to targeted therapies. At present, there is no established therapeutic approach for patients with advanced prostate cancer developing lineage plasticity or small cell neuroendocrine prostate cancer (NEPC) due to knowledge gaps in the underlying biology. Few clinical trials address questions in this space, and the outlook for patients remains poor. To move forward, urgently needed are: (i) a fundamental understanding of how lineage plasticity occurs and how it can best be defined; (ii) the temporal contribution and cooperation of emerging drivers; (iii) preclinical models that recapitulate biology of the disease and the recognized phenotypes; (iv) identification of therapeutic targets; and (v) novel trial designs dedicated to the entity as it is defined. This Perspective represents a consensus arising from the NCI Workshop on Lineage Plasticity and Androgen Receptor-Independent Prostate Cancer. We focus on the critical questions underlying lineage plasticity and AR-independent prostate cancer, outline knowledge and resource gaps, and identify strategies to facilitate future collaborative clinical translational and basic studies in this space.


Subject(s)
Androgen Receptor Antagonists/therapeutic use , Carcinoma, Small Cell/pathology , Cell Lineage , Cell Plasticity , Drug Resistance, Neoplasm , Prostatic Neoplasms/pathology , Receptors, Androgen/chemistry , Carcinoma, Small Cell/drug therapy , Humans , Male , Prostatic Neoplasms/drug therapy
4.
Clin Cancer Res ; 11(17): 6103-8, 2005 Sep 01.
Article in English | MEDLINE | ID: mdl-16144908

ABSTRACT

A group of investigators met at a Specialized Programs of Research Excellence Workshop to discuss key issues in the translation of biomarker discovery to the development of useful laboratory tests for cancer care. Development and approval of several new markers and technologies have provided informative examples that include more specific markers for prostate cancer, more sensitive tests for ovarian cancer, more objective analysis of tissue architecture and an earlier indication of response to treatment in breast cancer. Although there is no clear paradigm for biomarker development, several principles are clear. Marker development should be driven by clinical needs, including early cancer detection, accurate pretreatment staging, and prediction of response to treatment, as well as monitoring disease progression and response to therapy. Development of a national repository that uses carefully preserved, well-annotated tissue specimens will facilitate new marker development. Reference standards will be an essential component of this process. Both hospital-based and commercial laboratories can play a role in developing biomarkers from discovery to test validation. Partnering of academe and industry should occur throughout the process of biomarker development. The National Cancer Institute is in a unique position to bring together academe, industry, and the Food and Drug Administration to (a) define clinical needs for biomarkers by tumor type, (b) establish analytic and clinical paradigms for biomarker development, (c) discuss ways in which markers from different companies might be evaluated in combination, (d) establish computational methods to combine data from multiple biomarkers, (e) share information regarding promising markers developed in National Cancer Institute-supported programs, and (f) exchange data regarding new platforms and techniques that can accelerate marker development.


Subject(s)
Biomarkers, Tumor/analysis , Neoplasms/chemistry , Antineoplastic Agents/therapeutic use , Humans , Neoplasms/drug therapy
5.
Urol Oncol ; 32(8): 1108-15, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25443274

ABSTRACT

OBJECTIVE: To bridge gaps in translational science and develop the concepts for 2 novel biomarker-driven clinical trials: one in the presurgical setting and the other in the setting of bladder preservation with chemoradiation. METHODS AND MATERIALS: The National Cancer Institute sponsored a forum, "Novel Neoadjuvant Therapy for Bladder Cancer," which brought leading clinical and laboratory-based scientists together with the advocacy community. RESULTS: The group designed a neoadjuvant clinical trial to compare the clinical efficacy of the two frontline chemotherapy regimens (gemcitabine plus cisplatin versus MVAC) and the ability of a gene expression profiling-based algorithm (CoXEN) to predict complete pathological response. The trial was recently opened under the leadership of the Southwest Oncology Group (SWOG, S1314), receiving support for the biomarker studies from the NCI's BISQFP resource. A second clinical trial was planned that will examine the relationship between expression of the DNA repair protein MRE11 and complete response in patients treated with concurrent 5-fluorouracil/mitomycin C plus radiation. CONCLUSION: The meeting provided a unique opportunity to launch a collective effort to establish molecular-based therapies for muscle-invasive urothelial cancer. The goal is to use this framework to develop comparable trials with immunotherapy in non-muscle invasive cancers and to exploit the neoadjuvant platform to develop targeted therapy in muscle-invasive disease.


Subject(s)
Clinical Trials as Topic/methods , Urinary Bladder Neoplasms/therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chemoradiotherapy, Adjuvant/methods , Humans , National Cancer Institute (U.S.) , Neoadjuvant Therapy/methods , United States , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/radiotherapy
7.
Clin Cancer Res ; 16(6): 1745-55, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-20215558

ABSTRACT

The National Cancer Institute (NCI) Investigational Drug Steering Committee (IDSC) charged the Biomarker Task Force to develop recommendations to improve the decisions about incorporation of biomarker studies in early investigational drug trials. The Task Force members reviewed biomarker trials, the peer-reviewed literature, NCI and U.S. Food and Drug Administration (FDA) guidance documents, and conducted a survey of investigators to determine practices and challenges to executing biomarker studies in clinical trials of new drugs in early development. This document provides standard definitions and categories of biomarkers, and lists recommendations to sponsors and investigators for biomarker incorporation into such trials. Our recommendations for sponsors focus on the identification and prioritization of biomarkers and assays, the coordination of activities for the development and use of assays, and for operational activities. We also provide recommendations for investigators developing clinical trials with biomarker studies for scientific rationale, assay criteria, trial design, and analysis. The incorporation of biomarker studies into early drug trials is complex. Thus the decision to proceed with studies of biomarkers should be based on balancing the strength of science, assay robustness, feasibility, and resources with the burden of proper sample collection on the patient and potential impact of the results on drug development. The Task Force provides these guidelines in the hopes that improvements in biomarker studies will enhance the efficiency of investigational drug development.


Subject(s)
Biomarkers, Tumor/analysis , Clinical Trials as Topic/methods , Clinical Trials as Topic/standards , Drugs, Investigational/standards , Neoplasms/drug therapy , Pharmacy and Therapeutics Committee/organization & administration , Research Design , Endpoint Determination , Humans , National Cancer Institute (U.S.) , Neoplasms/chemistry , Safety , United States
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