MicroRNAs in colorectal cancer: translation of molecular biology into clinical application

MicroRNAs (miRNAs) are small non-coding RNAs 18-25 nucleotides in length that downregulate gene expression during various crucial cell processes such as apoptosis, differentiation and development. Changes in the expression profiles of miRNAs have been observed in a variety of human tumors, including colorectal cancer (CRC). Functional studies indicate that miRNAs act as tumor suppressors and oncogenes. These findings significantly extend Vogelstein's model of CRC pathogenesis and have shown great potential for miRNAs as a novel class of therapeutic targets. Several investigations have also described the ability of miRNA expression profiles to predict prognosis and response to selected treatments in CRC patients, and support diagnosis of CRC among cancer of unknown primary site. miRNAs' occurrence has been repeatedly observed also in serum and plasma, and miRNAs as novel minimally invasive biomarkers have indicated reasonable sensitivity for CRC detection and compare favorably with the fecal occult blood test. In this review, we summarize the knowledge regarding miRNAs' functioning in CRC while emphasizing their significance in pathogenetic signaling pathways and their potential to serve as disease biomarkers and novel therapeutic targets

Circulating miR-378 and miR-451 in serum are potential biomarkers for renal cell carcinoma

<p>Abstract</p> <p>Background</p> <p>There is no standard serum biomarker used for diagnosis or early detection of recurrence for renal cell carcinoma (RCC) patients. MicroRNAs (miRNAs) are abundant and highly stable in blood serum, and have been recently described as powerful circulating biomarkers in a wide range of solid cancers. Our aim was to identify miRNA signature that can distinguish the blood serum of RCC patients and matched healthy controls and validate identified miRNAs as potential biomarkers for RCC.</p> <p>Methods</p> <p>In the screening phase of the study, blood serum of 15 RCC patients and 12 matched healthy controls were analyzed by use of the TaqMan Low-Density Arrays enabling parallel identification of expression levels of 667 miRNAs through qRT-PCR-based approach. In the validation phase, identified miRNAs were further evaluated on the independent group of 90 RCC patients and 35 matched healthy controls by use of individual qRT-PCR assays and statistically evaluated.</p> <p>Results</p> <p>We identified 30 miRNAs differentially expressed between serum of RCC patients and healthy controls: 19 miRNAs were up-regulated and 11 miRNAs were down-regulated in RCC patients. MiR-378, miR-451 and miR-150 were further evaluated in the independent group of patients, and two of them were successfully validated: levels of miR-378 were increased (p = 0.0003, AUC = 0.71), miR-451 levels were decreased (p < 0.0001, AUC = 0.77) in serum of RCC patients. Combination of miR-378 and miR-451 enable identification of RCC serum with the sensitivity of 81%, specificity 83% and AUC = 0.86.</p> <p>Conclusions</p> <p>Circulating miRNAs in serum are promising biomarkers in RCC.</p

Epidemiologie, prevence a léčba kolorektálního karcinomu dle dostupných českých a mezinárodních dat

Nádory tlustého střeva a konečníku patří mezi nejčastější onkologické diagnózy. V České republice je každoročně nově diagnostikováno téměř 8 500 pacientů s kolorektálním karcinomem a přibližně 3 900 osob tomuto onemocnění každým rokem podlehne. Celková prevalence přesáhne v roce 2012 hranici 55 000 osob. Společenské, etické i ekonomické důsledky vyplývající z takto vysoké zátěže jsou zřejmé. Publikace „Epidemiologie, prevence a léčba kolorektálního karcinomu dle dostupných českých a mezinárodních dat“ přináší ucelený přehled epidemiologické a léčebné zátěže české populace touto chorobou a věnuje se krátkodobým a dlouhodobým predikcím dalšího vývoje. Situace je rovněž hodnocena v mezinárodním srovnání, neboť v hodnotách incidence a mortality kolorektálního karcinomu obsazuje ČR přední příčky evropských i světových statistik. Z mezinárodních studií však také vyplývá pozitivní poznatek, že většině nádorů tlustého střeva a konečníku lze předejít účinnou prevencí. Kromě primární prevence je zde hlavním nástrojem organizovaný populační screening, který je založen na testech krvácení do stolice a na kolonoskopii. Otázkám prevence a výsledkům screeningu kolorektálního karcinomu jsou v publikaci věnovány zvláštní kapitoly. Ačkoli nejnovější data dokládají rostoucí výkonnost českého screeningu, celkově dosažené pokrytí populace bohužel stále není dostatečné. To platí pro včasný záchyt kolorektálního karcinomu obecně, neboť v ČR je setrvale téměř 50 % nových onemocnění diagnostikováno v pokročilých klinických stadiích, a tedy s výrazně sníženou šancí na vyléčení nebo dlouhodobé přežití pacienta. Publikace rovněž hodnotí přežití dosahované u českých pacientů jakožto zásadní ukazatel výsledků léčebné péče, u kterého v posledních 15 letech zaznamenáváme statisticky významné zlepšení. Pravděpodobnost 5letého relativního přežití je u včasně diagnostikovaného kolorektálního karcinomu v klinickém stadiu i vyšší než 88%. Tato čísla opět potvrzují nutnost účinné prevence a posílení screeningu tohoto preventabilního onemocnění. V tomto směru má publikace ambici informovat odbornou i laickou veřejnost, a proto věnuje značný prostor přehledu dostupných informačních zdrojů.The book aims to inform expert and general public about epidemiology of colorectal carcinoma in the Czech Republic and priorities resulting from high population burden for prevention, diagnostics, and treatment of this severe disease. A number of invited experts assess selected information sources that representatively describe performance and quality of preventive programmes and results of CRC treatment in the Czech Republic

MiR-34b is associated with clinical outcome in triple-negative breast cancer patients

<p>Abstract</p> <p>Background</p> <p>Breast cancer is the most common malignancy with the highest incidence rates among women worldwide. Triple-negative breast cancer (TNBC) represents the major phenotype of basal-like molecular subtype of breast cancer, characterized by higher incidence in young women and a very poor prognosis. MicroRNAs (miRNAs) are small non-coding RNAs playing significant role in the pathogenesis of many cancers including breast cancer. Therefore, miRNAs are also potential prognostic and/or predictive biomarkers in triple-negative breast cancer patients.</p> <p>Methods</p> <p>Thirty-nine TNBC patients with available formalin-fixed paraffin-embedded (FFPE) tissues were enrolled in the study. MiR-34a, miR-34b, and miR-34c were analyzed using qRT-PCR and correlated to clinico-pathological features of TNBC patients.</p> <p>Results</p> <p>Expression levels of miR-34b significantly correlate with disease free survival (DFS) (<it>p </it>= 0.0020, log-rank test) and overall survival (OS) (<it>p </it>= 0.0008, log-rank test) of TNBC patients. No other significant associations between miR-34a, miR-34b, and miR-34c with available clinical pathological data were observed.</p> <p>Conclusions</p> <p>MiR-34b expression negatively correlates with disease free survival and overall survival in TNBC patients. Thus, miR-34b may present a new promising prognostic biomarker in TNBC patients, but independent validations are necessary.</p

Estimating the number of colorectal cancer patients treated with anti-tumour therapy in 2015: the analysis of the Czech National Cancer Registry

<p>Abstract</p> <p>Background</p> <p>Colorectal cancer (CRC) represents a serious health care problem in the Czech Republic, introducing a need for a prospective modelling of the incidence and prevalence rates. The prevalence of patients requiring anti-tumour therapy is also of great importance, as it is directly associated with planning of health care resources.</p> <p>Methods</p> <p>This work proposes a population-based model for the estimation of stage-specific prevalence of CRC patients who will require active anti-tumour therapy in a given year. Its applicability is documented on records of the Czech National Cancer Registry (CNCR), which is used to estimate the number of patients potentially treated with anti-tumour therapy in the Czech Republic in 2015.</p> <p>Results</p> <p>Several scenarios are adopted to cover the plausible development of the incidence and survival rates, and the probability of an anti-tumour therapy initiation. Based on the scenarios, the model predicts an increase in CRC prevalence from 13% to 30% in comparison with the situation in 2008. Moreover, the model predicts that 10,074 to 11,440 CRC patients will be indicated for anti-tumour therapy in the Czech Republic in 2015. Considering all patients with terminal cancer recurrence and all patients primarily diagnosed in stage IV, it is predicted that 3,485 to 4,469 CRC patients will be treated for the metastatic disease in 2015, which accounts for more than one third (34-40%) of all CRC patients treated this year.</p> <p>Conclusions</p> <p>A new model for the estimation of the number of CRC patients requiring active anti-tumour therapy is proposed in this paper. The model respects the clinical stage as the primary stratification factor and utilizes solely the population-based cancer registry data. Thus, no specific hospital data records are needed in the proposed approach. Regarding the short-term prediction of the CRC burden in the Czech Republic, the model confirms a continuous increase in the burden that must be accounted for in the future planning of health care in the Czech Republic.</p