BACKGROUND/AIM: The monoclonal antibody bevacizumab is a standard drug used in combination with oxaliplatin (FOLFOX) or irinotecan (FOLFIRI) based chemotherapy in the first or second-line treatment of metastatic colorectal cancer (mCRC). Our previous study identified and subsequently validated 4 microRNAs in a small group of patients as predictors of the therapeutic response to bevacizumab combined with chemotherapy. The aim of this follow-up study is to confirm the predictive ability of these tissue miRNAs in a larger independent cohort of mCRC patients. PATIENTS AND METHODS: The retrospective study included 92 patients with generalized-radically inoperable tumors treated with the combined therapy of bevacizumab/FOLFOX in a standard regimen. RESULTS: Expression levels of candidate miRNA biomarkers (miR-92b-3p, miR-3156-5p, miR-10a-5p and miR-125a-5p) were determined in tumor tissue specimens and statistically evaluated. MiR-92b-3p and miR-125a-5p were confirmed to be associated with radiological response according to RECIST criteria (p=0.005 and 0.05, respectively) and to be up-regulated in responders to bevacizumab/FOLFOX therapy. Higher levels of miR-92b-3p were also significantly associated with extended progression-free survival (p=0.024). CONCLUSION: We have successfully confirmed miR-92b-3p to be up-regulated in tumor tissue of mCRC patients with good response to bevacizumab/FOLFOX therapy.

• Keywords
• Bevacizumab, metastatic colorectal cancer, microRNA, predictive biomarker, progression-free survival, validation,
• MeSH
• Bevacizumab therapeutic use   MeSH
• Biomarkers MeSH
• Fluorouracil MeSH
• Colorectal Neoplasms * drug therapy   genetics   MeSH
• Humans MeSH
• MicroRNAs * genetics   MeSH
• Follow-Up Studies MeSH
• Antineoplastic Combined Chemotherapy Protocols therapeutic use   MeSH
• Retrospective Studies MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Bevacizumab MeSH
• Biomarkers MeSH
• Fluorouracil MeSH
• MicroRNAs * MeSH

MicroRNAs (miRNAs) regulate gene expression in a tissue-specific manner. However, little is known about the miRNA expression changes induced by the therapy in rectal cancer (RC) patients. We evaluated miRNA expression levels before and after therapy and identified specific miRNA signatures reflecting disease course and treatment responses of RC patients. First, miRNA expression levels were assessed by next-generation sequencing in two plasma samplings (at the time of diagnosis and a year after) from 20 RC patients. MiR-122-5p and miR-142-5p were classified for subsequent validation in plasma and plasma extracellular vesicles (EVs) on an independent group of RC patients (n=107). Due to the intrinsic high differences in miRNA expression levels between samplings, cancer-free individuals (n=51) were included in the validation phase to determine the baseline expression levels of the selected miRNAs. Expression levels of these miRNAs were significantly different between RC patients and controls (for all p <0.001). A year after diagnosis, miRNA expression profiles were significantly modified in patients responding to treatment and were no longer different from those measured in cancer-free individuals. On the other hand, patients not responding to therapy maintained low expression levels in their second sampling (miR-122-5p: plasma: p=0.05, EVs: p=0.007; miR-142-5p: plasma: p=0.008). Besides, overexpression of miR-122-5p and miR-142-5p in RC cell lines inhibited cell growth and survival. This study provides novel evidence that circulating miR-122-5p and miR-142-5p have a high potential for RC screening and early detection as well as for the assessment of patients' outcomes and the effectiveness of treatment schedule.

• Keywords
• biomarker, liquid biopsy, miR-122-5p, miR-142-5p, microRNA, plasma, rectal cancer,
• Publication type
• Journal Article MeSH

Growing evidence suggests that microRNAs are involved in the development and progression of colorectal cancer (CRC). In the present study, deregulation and functioning of tumor-suppressive miR-215-5p was evaluated in CRC. In total, 448 tumor tissues and 325 paired adjacent healthy tissues collected from Czech and Spain cohorts of CRC patients have been used for miR-215-5p expression analyses. A series of in vitro experiments have been performed using transient transfection of miR-215-5p mimics into four CRC cell lines to identify specific cellular processes affected by miR-215-5p. Further, the effects of miR-215-5p on tumor growth were evaluated in vivo using NSG mice and stable cell line overexpressing miR-215-5p. Target mRNAs of miR-215-5p were tested using luciferase assay and western blot analyses. We found that miR-215-5p is significantly downregulated in tumor tissues compared with non-tumor adjacent tissues and its decreased levels correlate with the presence of lymph node metastases, tumor stage, and shorter overall survival in CRC patients. Overexpression of miR-215-5p significantly reduced proliferation, clonogenicity, and migration of CRC cells, lead to cell cycle arrest in G2/M phase and p53-dependent induction of apoptosis. The ability of miR-215-5p to inhibit tumor growth was confirmed in vivo. Finally, we confirmed epiregulin and HOXB9 to be the direct targets of miR-215-5p. As epiregulin is EGFR ligand and HOXB9 is its transcriptional inducer, we suggest that the main molecular link between miR-215-5p and CRC cells phenotypes presents the EGFR signaling pathway, which is one of the canonical pathogenic pathways in CRC.

• Publication type
• Journal Article MeSH

Colorectal cancer has been a leading cause of cancer-related morbidity and mortality. For the research and individualization of therapy, primary cell lines of the colorectal cancer appear to be still an invaluable tool. We evaluated the differences in metastatic potential between four isolated primary colon cancer cells and cells derived from their lymph node metastasis. These results were compared with correspond immortalized cells-SW480 and SW620, respectively. The ability to migrate was tested using real-time measurement in xCELLigence system. Expressions of molecules involved in adhesion and invasion processes were examined using RT-PCR and western blot analysis. Furthermore, impact of cytotoxic effect of selected chemotherapeutics (irinotecan, oxaliplatin) and biological therapy (bevacizumab, cetuximab, panitumumab) was assessed by the WST assay. As expected, cell lines derived from lymph node migrated more aggressively and higher expression of adhesion molecules ICAM-1, EpCAM, and N-cadherin was detected. The expression of MMP-2 and -9 was elevated, on the other hand, in cell lines derived from primary tumor cancer cells as well as the expression of miR-21, miR-29a, and miR-200a. The most pronounced cytotoxic effect has been recorded with oxaliplatin and irinotecan (IC50 = 48.23 resp. 0.11 μg/ml), especially in cells originating from lymph node metastases. In total, comparison of isolated cell lines and immortalized cell lines has shown many similarities, as well as several differences. Adhesion/invasion molecules and several miRNAs, which play an important role in tumor development and the invasive and migratory behavior, could be a useful therapeutic target in malignant colorectal cancer.

• Keywords
• Anticancer therapy, Colorectal carcinoma, Lymph node metastasis, Tumor progression, microRNA,
• MeSH
• Cell Adhesion genetics   MeSH
• Colorectal Neoplasms drug therapy   genetics   pathology   MeSH
• Humans MeSH
• Lymphatic Metastasis pathology   MeSH
• Lymph Nodes pathology   MeSH
• Matrix Metalloproteinase 2 genetics   MeSH
• Matrix Metalloproteinase 9 genetics   MeSH
• MicroRNAs genetics   MeSH
• Cell Adhesion Molecules genetics   MeSH
• Cell Line, Tumor MeSH
• Cell Movement genetics   MeSH
• Disease Progression MeSH
• Antineoplastic Agents pharmacology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH
• Names of Substances
• Matrix Metalloproteinase 2 MeSH
• Matrix Metalloproteinase 9 MeSH
• MicroRNAs MeSH
• Cell Adhesion Molecules MeSH
• Antineoplastic Agents MeSH

Renal cell carcinoma (RCC) is the most common neoplasm of adult kidney accounting for about 3 % of adult malignancies. MicroRNAs (miRNAs) are a class of naturally occurring, short non-coding RNAs that regulate gene expression at the post-transcriptional level. We determined global miRNA expression profiles of RCC and parallel renal parenchyma tissues by using quantitative reverse transcriptase-polymerase chain reaction-based TaqMan low-density arrays. Afterward, we validated the difference in miR-210 expression levels on the larger group of RCC patients (35 RCC versus 10 non-tumorous parenchyma samples). Functional in vitro experiments were performed on ACHN and CAKI-2 RCC cell lines transfected with miRNA-210 inhibitor. Cell viability, apoptosis, cell cycle, scratch wound migration assay, and invasion assay (xCELLigence) were performed. We have identified original ccRCC-specific miRNA signature in clinical samples (73 miRNAs were significantly downregulated and five miRNAs upregulated (P < 0.003)). Increased expression levels of miR-210 in RCC tumor tissue were independently validated. We observed decreased viability of ACHN and CAKI-2 cells and accumulation of CAKI-2 in G2 phase of cell cycle after silencing of miR-210 expression. Downregulation of miR-210 also reduced the migratory and invasive potential of ACHN metastatic RCC cells. Moreover, we showed downregulation of HIF1a protein in both cell lines after miR-210 silencing indicating participation of miR-210 in hypoxic processes of RCC not only through regulation of its target mRNAs but also by indirect regulation of HIF1a. To our knowledge, this is the first report to show miR-210 regulatory effects on cell migration, invasive potential, and HIF1a protein in RCC cells.

• MeSH
• Apoptosis MeSH
• Cell Cycle MeSH
• Adult MeSH
• Down-Regulation MeSH
• Hypoxia-Inducible Factor 1, alpha Subunit metabolism   MeSH
• Neoplasm Invasiveness MeSH
• Carcinoma, Renal Cell genetics   metabolism   pathology   MeSH
• Cell Cycle Checkpoints MeSH
• Middle Aged MeSH
• Humans MeSH
• RNA, Messenger genetics   metabolism   MeSH
• MicroRNAs biosynthesis   genetics   MeSH
• Biomarkers, Tumor genetics   metabolism   MeSH
• Cell Line, Tumor MeSH
• Kidney Neoplasms genetics   metabolism   pathology   MeSH
• Cell Movement MeSH
• Gene Expression Regulation, Neoplastic MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Gene Expression Profiling MeSH
• Gene Silencing MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Hypoxia-Inducible Factor 1, alpha Subunit MeSH
• HIF1A protein, human MeSH Browser
• RNA, Messenger MeSH
• MicroRNAs MeSH
• MIRN210 microRNA, human MeSH Browser
• Biomarkers, Tumor MeSH

BACKGROUND: Rectal cancer accounts for approximately one third of all colorectal cancers (CRC), which belong among leading causes of cancer deaths worldwide. Standard treatment for locally advanced rectal cancer (cT3/4 and/or cN+) includes neoadjuvant chemoradiotherapy with fluoropyrimidines (capecitabine or 5-fluorouracil) followed by radical surgical resection. Unfortunately, a significant proportion of tumors do not respond enough to the neoadjuvant treatment and these patients are at risk of relapse. MicroRNAs (miRNAs) are small non-coding RNAs playing significant roles in the pathogenesis of many cancers including rectal cancer. MiRNAs could present the new predictive biomarkers for rectal cancer patients. METHODS: We selected 20 patients who underwent neoadjuvant chemoradiotherapy for advanced rectal cancer and whose tumors were classified as most sensitive or resistant to the treatment. These two groups were compared using large-scale miRNA expression profiling. RESULTS: Expression levels of 8 miRNAs significantly differed between two groups. MiR-215, miR-190b and miR-29b-2* have been overexpressed in non-responders, and let-7e, miR-196b, miR-450a, miR-450b-5p and miR-99a* have shown higher expression levels in responders. Using these miRNAs 9 of 10 responders and 9 of 10 non-responders (p < 0.05) have been correctly classified. CONCLUSIONS: Our pilot study suggests that miRNAs are part of the mechanisms that are involved in response of rectal cancer to the chemoradiotherapy and that miRNAs may be promising predictive biomarkers for such patients. In most miRNAs we identified (miR-215, miR-99a*, miR-196b, miR-450b-5p and let-7e), the connection between their expression and radioresistance or chemoresistance to inhibitors of thymidylate synthetase was already established.

• MeSH
• Adenocarcinoma genetics   metabolism   pathology   surgery   therapy   MeSH
• Capecitabine MeSH
• Chemoradiotherapy * MeSH
• Drug Resistance, Neoplasm genetics   MeSH
• Deoxycytidine analogs & derivatives   pharmacology   therapeutic use   MeSH
• Adult MeSH
• Fluorouracil analogs & derivatives   pharmacology   therapeutic use   MeSH
• Combined Modality Therapy MeSH
• Middle Aged MeSH
• Humans MeSH
• MicroRNAs biosynthesis   genetics   MeSH
• Neoplasm Proteins antagonists & inhibitors   physiology   MeSH
• Rectal Neoplasms genetics   metabolism   pathology   surgery   therapy   MeSH
• Neoadjuvant Therapy * MeSH
• Pilot Projects MeSH
• Antimetabolites, Antineoplastic pharmacology   therapeutic use   MeSH
• Gene Expression Regulation, Neoplastic * MeSH
• Retrospective Studies MeSH
• RNA, Neoplasm biosynthesis   genetics   MeSH
• Aged MeSH
• Gene Expression Profiling MeSH
• Thymidylate Synthase antagonists & inhibitors   physiology   MeSH
• Radiation Tolerance genetics   MeSH
• Treatment Outcome MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH
• Names of Substances
• Capecitabine MeSH
• Deoxycytidine MeSH
• Fluorouracil MeSH
• MicroRNAs MeSH
• Neoplasm Proteins MeSH
• Antimetabolites, Antineoplastic MeSH
• RNA, Neoplasm MeSH
• Thymidylate Synthase MeSH

PURPOSE: MicroRNA-21 (miR-21) is one of the miRNAs that are frequently and highly overexpressed in tumor tissue of colorectal cancer (CRC) patients; however, only a little is known about its functional role in CRC. METHODS: We examined the expression level of miR-21 in 44 paired samples of tumoral and non-tumoral colon tissues diagnosed for CRC using TaqMan real-time PCR method. Furthermore, we used miR-21 inhibitor (anti-miR-21) to transient knockdown of miR-21 in DLD-1 colon cancer cells and examined the effects of miR-21 silencing on viability, apoptosis, chemosensitivity, cell cycle, and migration of DLD1 cells. RESULTS: The expression levels of miR-21 were significantly increased in CRC tumor tissue (P < 0.0001). Significant differences in miR-21 levels were observed also between CRC tissues of patients with CRC in different clinical stages: I vs. II (P = 0.033) and I vs. IV (P = 0.021). Kaplan-Meier analysis proved that the miR-21 expression levels are correlated to shorter overall survival of CRC patients (P = 0.0341). MiR-21 silencing in DLD1 cell line had no effect on the cell viability; however, when combined with chemotherapeutics (5-FU, L-OHP, and SN38), it contributed to the decrease of cell viability. Suppression of miR-21 decreased cell migration ability of DLD-1 cells by nearly 30 % (P = 0.016). CONCLUSION: We have confirmed the overexpression of miR-21 in CRC samples and its correlation with advanced disease and shorter overall survival. These findings could be described in part by the fact that CRC cells with increased expression of miR-21 have higher migration ability.

• MeSH
• Apoptosis drug effects   genetics   MeSH
• Cell Cycle drug effects   genetics   MeSH
• Kaplan-Meier Estimate MeSH
• Colorectal Neoplasms drug therapy   genetics   pathology   MeSH
• Middle Aged MeSH
• Humans MeSH
• MicroRNAs antagonists & inhibitors   genetics   metabolism   MeSH
• Cell Line, Tumor MeSH
• Colonic Neoplasms genetics   pathology   MeSH
• Cell Movement drug effects   genetics   MeSH
• Antineoplastic Agents pharmacology   therapeutic use   MeSH
• Gene Expression Regulation, Neoplastic drug effects   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Cell Survival drug effects   genetics   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• MicroRNAs MeSH
• MIRN21 microRNA, human MeSH Browser
• Antineoplastic Agents MeSH

MicroRNAs (miRNAs) constitute a robust regulatory network with post-transcriptional regulatory efficiency for almost one half of human coding genes, including oncogenes and tumour suppressors. We determined the expression profile of 667 miRNAs in colorectal cancer (CRC) tissues and paired non-tumoural tissues and identified 42 differentially expressed miRNAs. We chose miR-215, miR-375, miR-378, miR-422a and miR-135b for further validation on an independent cohort of 125 clinically characterized CRC patients and for in vitro analyses. MiR-215, miR-375, miR-378 and miR-422a were significantly decreased, whereas miR-135b was increased in CRC tumour tissues. Levels of miR-215 and miR-422a correlated with clinical stage. MiR-135b was associated with higher pre-operative serum levels of CEA and CA19-9. In vitro analyses showed that ectopic expression of miR-215 decreases viability and migration, increases apoptosis and promotes cell cycle arrest in DLD-1 and HCT-116 colon cancer cell lines. Similarly, overexpression of miR-375 and inhibition of miR-135b led to decreased viability. Finally, restoration of miR-378, miR-422a and miR-375 inhibited G1/S transition. These findings indicate that miR-378, miR-375, miR-422a and miR-215 play an important role in CRC as tumour suppressors, whereas miR-135b functions as an oncogene; both groups of miRNA contribute to CRC pathogenesis.

• MeSH
• Apoptosis genetics   MeSH
• Adult MeSH
• Colorectal Neoplasms genetics   pathology   MeSH
• Cell Cycle Checkpoints genetics   MeSH
• Middle Aged MeSH
• Humans MeSH
• MicroRNAs genetics   MeSH
• Cell Line, Tumor MeSH
• Cell Movement genetics   MeSH
• Gene Expression Regulation, Neoplastic * MeSH
• Reproducibility of Results MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Genes, Tumor Suppressor MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• MicroRNAs MeSH
• MIRN135 microRNA, human MeSH Browser
• MIRN215 microRNA, human MeSH Browser
• MIRN375 microRNA, human MeSH Browser
• MIRN378 microRNA, human MeSH Browser
• MIRN422 microRNA, human MeSH Browser

AIM: To investigate whether selected single nucleotide polymorphisms (SNPs) in miR-196a2, miR-27a and miR-146a genes are associated with sporadic colorectal cancer (CRC). METHODS: In order to investigate the effect of these SNPs in CRC, we performed a case-control study of 197 cases of sporadic CRC and 212 cancer-free controls originating from the Central-European Caucasian population using TaqMan Real-Time polymerase chain reaction and allelic discrimination analysis. RESULTS: The genotype and allele frequencies of SNPs were compared between the cases and the controls. None of the performed analysis showed any statistically significant results. CONCLUSION: Our data suggest a lack of association between rs11614913, rs895819 and rs2910164 and colorectal cancer risk in the Central-European Caucasian population, a population with an extremely high incidence of sporadic colorectal cancer.

• Keywords
• Association study, Colorectal cancer, MicroRNA, Single nucleotide polymorphism,
• MeSH
• Adenocarcinoma ethnology   genetics   pathology   MeSH
• White People genetics   MeSH
• Gene Frequency MeSH
• Genetic Predisposition to Disease MeSH
• Risk Assessment MeSH
• Incidence MeSH
• Polymorphism, Single Nucleotide * MeSH
• Colorectal Neoplasms ethnology   genetics   pathology   MeSH
• Real-Time Polymerase Chain Reaction MeSH
• Middle Aged MeSH
• Humans MeSH
• Logistic Models MeSH
• MicroRNAs genetics   MeSH
• Odds Ratio MeSH
• Risk Factors MeSH
• Chi-Square Distribution MeSH
• Aged MeSH
• Case-Control Studies MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic epidemiology   MeSH
• Names of Substances
• MicroRNAs MeSH
• MIRN146 microRNA, human MeSH Browser
• MIRN196 microRNA, human MeSH Browser
• MIRN27 microRNA, human MeSH Browser

For the many years, the central dogma of molecular biology has been that RNA functions mainly as an informational intermediate between a DNA sequence and its encoded protein. But one of the great surprises of modern biology was the discovery that protein-coding genes represent less than 2% of the total genome sequence, and subsequently the fact that at least 90% of the human genome is actively transcribed. Thus, the human transcriptome was found to be more complex than a collection of protein-coding genes and their splice variants. Although initially argued to be spurious transcriptional noise or accumulated evolutionary debris arising from the early assembly of genes and/or the insertion of mobile genetic elements, recent evidence suggests that the non-coding RNAs (ncRNAs) may play major biological roles in cellular development, physiology and pathologies. NcRNAs could be grouped into two major classes based on the transcript size; small ncRNAs and long ncRNAs. Each of these classes can be further divided, whereas novel subclasses are still being discovered and characterized. Although, in the last years, small ncRNAs called microRNAs were studied most frequently with more than ten thousand hits at PubMed database, recently, evidence has begun to accumulate describing the molecular mechanisms by which a wide range of novel RNA species function, providing insight into their functional roles in cellular biology and in human disease. In this review, we summarize newly discovered classes of ncRNAs, and highlight their functioning in cancer biology and potential usage as biomarkers or therapeutic targets.

• MeSH
• Humans MeSH
• Neoplasms genetics   MeSH
• RNA, Untranslated genetics   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• RNA, Untranslated MeSH