Expression levels of microRNA-375 in colorectal carcinoma

Abstract

Abstract. MicroRNAs are small, non-coding RNAs of endogenous origin. They have been increasingly shown to have altered expressions in many cancer types. The expression levels of miR-375 have not been comprehensively investigated in colorectal cancer. In this study, total RNA was extracted from 95 pairs of colorectal cancer tissues and non-tumor adjacent tissues, as well as from three colorectal cancer cell lines (HT-29, HCT-116 and SW-620). After polyadenylation and reverse transcription, we determined the expression levels of miR-375 by real-time PCR and calculated the difference in expression using the 2 -∆∆Ct method. We assessed the correlation between the expression levels of miR-375 and clini copathological characteristics of colorectal cancer. miR-375 expression was frequently downregulated in the colorectal cancer tissues compared to the non-tumor counterparts (p<0.001; paired t-test). Moreover, a significantly low expression of miR-375 was also found in the colorectal cancer cell lines (HT-29, p=0.002; HCT-116, p<0.001; SW-620, p=0.004; paired t-test). However, there were no significant correlations between the low expression of miR-375 and tumor size, histological grade, pT stage, pN stage and pTNM stage (all P>0.05, non-parametric test; Mann-Whitney U test between two groups and Kruskal-Wallis H test for three or more groups). miR-375 may be involved in the carcinogenesis of colorectal cancers and may be a potential biomarker for colorectal cancers.

Exosome-Carried microRNA-375 Inhibits Cell Progression and Dissemination via Bcl-2 Blocking in Colon Cancer

“…In CRC, only recent and few studies have tried to identify the role played by miR-375. In this direction, miR-375 has been found to be significantly under-expressed, without any correlation to tumor size, histological grade, pT stage, pN stage and pTNM stage [56,57], and that in vitro and in vivo experiments proved that overexpression of miR-375 may facilitate a direct and targeted growth inhibition for CRC cells either by targeting PI3K/Akt signaling pathway or by stimulating apoptosis via targeting BIRC5 and BCL2L1 [58].…”

“…In most CRC tumors (90%) a regulatory factor of the Wnt/β-catenin signaling pathway is mutated [the Wnt ligand which initiates signaling through the Frizzled (FZD) receptor is one of the known targets of miR-375] [15,19]. Several studies identified miR-375 to be down-regulated in CRC, without mentioning its role for liver metastasis progression [22,23], but underlying its capacity to inhibit primary tumor growth by targeting PI3K/Akt signaling pathway [24] and by stimulating apoptosis by targeting YAP1 [25]. To summarize, more and more data show that a down-regulated miR-375, either found in primary tumor specimens or via exosomes in circulating fluids, may subclinically identify the presence or the persistence of cancer, underlining a poor prognosis in many solid tumors [26,27].…”

“…Several studies identified miR-375 to be down-regulated in CRC, without mentioning its role for liver metastasis progression [22,23], but underlying its capacity to inhibit primary tumor growth by targeting PI3K/Akt signaling pathway [24] and by stimulating apoptosis by targeting YAP1 [25]. To summarize, more and more data show that a down-regulated miR-375, either found in primary tumor specimens or via exosomes in circulating fluids, may subclinically identify the presence or the persistence of cancer, underlining a poor prognosis in many solid tumors [26,27]. No data was found in relation to miR-375 and Bcl-2 blocking, responsible for tumoral progression and dissemination.…”

MicroRNA-375 suppresses human colorectal cancer metastasis by targeting Frizzled 8

“…Several in vitro and in vivo studies have shown that pancreatic miRNA-375 directly targets PDK1, plays key roles in the glucose regulation of insulin gene expression and β-cell growth and is down-regulated in pancreatic carcinoma [15]. Recently, Dai et al reported that miR-375 expression is frequently down-regulated in colorectal cancer tissues compared with the non-tumor counterparts [36]. We also demonstrated that the level of miR-375 was significantly decreased in the plasma of CRC patients and correlated well with the expression observed in tissue samples, suggesting that miR-375 may serve an alternative biomarker of minimally invasive CRC [17].…”

Molecular binary classification of NSCLC: miR-375 is a potential biomarker to differentiate SQCC from ADCC in Indian NSCLC patients

“…Growing evidence suggested that it was down-regulated in esophageal SQCC, Barrett's carcinoma, glioma, colorectal cancer, hepatocellular carcinoma, lung cancer, and associated with advanced-stage metastasis and unfavorable treatment outcome [14][15][16][17]. Also, evidence from the previous study suggested that miR-375 plays a dual role in NSCLC as it was over-expressed in ADCC and suppressed in SQCC, proving the oncogenic nature in ADCC and tumor suppressor in SQCC [18].…”