Objective MicroRNA (miRNA) expression profile can be used as prognostic marker for human cancers. We aim to explore the significance of miRNAs in colorectal cancer (CRC) metastasis. Design We performed miRNA microarrays using primary CRC tissues from patients with and without metastasis, and validated selected candidates in 85 CRC samples by qRT-PCR. We tested metastatic activity of selected miRNAs, and identified miRNA targets by prediction algorithms, qRT-PCR, western blot and luciferase assays. Clinical outcomes were analyzed in six sets of CRC cases (n=449) including The Cancer Genome Atlas consortium and correlated with miR-224 status. We used the Kaplan-Meier method and log-rank test to assess the difference in survival between patients with low or high levels of miR-224 expression. Results MiR-224 expression increases consistently with tumor burden and microsatellite stable (MSS) status, and miR-224 enhances CRC metastasis in vitro and in vivo. We identified SMAD4 as a miR-224 target, and observed negative correlation (Spearman Rs=−0.44, p<0.0001) between SMAD4 and miR-224 expression in clinical samples. Patients with high miR-224 levels display shorter overall survival in multiple CRC cohorts (p=0.0259, 0.0137, 0.0207, 0.0181, 0.0331 and 0.0037 respectively), and shorter metastasis-free survival (hazard ratio 6.51, 95% CI 1.97-21.51, p=0.0008). In the TCGA set, combined analysis of miR-224 with SMAD4 expression enhanced correlation with survival (hazard ratio 4.12, 95% CI 1.1-15.41, p=0.0175). Conclusion MiR-224 promotes CRC metastasis, at least in part, through the regulation of SMAD4. MiR-224 expression in primary CRC, alone or combined with its targets, may have prognostic value for CRC patient survival.

The cancer-risk-associated rs6983267 single nucleotide polymorphism (SNP) and the accompanying long noncoding RNA in the highly amplified 8q24.21 region have been implicated in cancer predisposition, although causality has not been established. Here, using allele-specific transgenic mice, we demonstrate that overexpression leads to spontaneous myeloid malignancies. We further identified that is overexpressed in bone marrow and peripheral blood of myelodysplastic/myeloproliferative neoplasms (MDS/MPN) patients. induces global deregulation of gene expression by down-regulating EZH2 in vitro and in vivo in an allele-specific manner. We also identified a novel non-APOBEC, non-ADAR, RNA editing at the SNP locus in MDS/MPN patients and-transgenic mice. The RNA transcribed from the SNP locus in malignant hematopoietic cells have different allelic composition from the corresponding genomic DNA, a phenomenon rarely observed in normal cells. Our findings provide fundamental insights into the functional role of rs6983267 SNP and in myeloid malignancies.

The present study brings to the forefront new data that suggest miR-375 as a new player in controlling the pathways responsible for inhibiting the natural history of CRC tumor cells, via the Bcl-2 pathway.

MicroRNAs or miRNAs are small non-coding RNAs that regulate gene expression. Their discovery has brought new knowledge in biological processes of cancer. Involvement of miRNAs in cancer development includes several major pathways from cell transformation to tumor cell development, metastasis and resistance to treatment. The first part of this review discusses miRNAs function in the intrinsic and extrinsic pathways of apoptosis. Due to the fact that many miRNAs that regulate apoptosis have been shown to play a major role in tumor cell resistance to treatment, in the second part of the review we aim at discussing miRNAs potential in becoming curative molecules.

BackgroundBreast cancer is a highly heterogeneous pathology, exhibiting a number of subtypes commonly associated with a poor outcome. Due to their high stability, microRNAs are often regarded as non-invasive cancer biomarkers, having an expression pattern specific for their ‘cell of origin’.MethodTriple negative breast cancer (TNBC: ER-, PR-, Her-2-) and double positive breast cancer (DPBC: ER+, PR+, Her-2) miRNA expression patterns were obtained by analysis of the TCGA (The Cancer Genome Atlas) data, followed by PCR-array analysis on plasma samples from 20 TNBC patients, 14 DPBC patients and 11 controls.ResultsThree downregulated and nine upregulated miRNAs were obtained from the TNBC analysis. Five overexpressed miRNAs were identified in the DPBC group. Four of the dysregulated miRNAs (miR-10a, miR-125b, miR-210 and miR-489) were common for both groups. The cluster miR-17-92 (miR-17, miR-20a, miR-20b, and miR-93), along with miR-130, miR-22 and miR-29a/c, were found to differentiate between TNBC and DPBC. A panel of five transcripts (miR-10a, miR-125, miR-193b, miR-200b and miR-489) was validated in a new set of plasma samples. The overlapping of TCGA and plasma profiling data revealed miR-200b, miR-200c, miR-210 and miR-29c as common signature. MiR-200b was validated on additional normal and tumor tissue samples. The expression level of this transcript from the TCGA data was correlated with lung and bone metastatic genes.ConclusionThe miR-200b presents a great potential for the future advancements in the diagnostic/prognostic and therapeutic approach of TNBC, along with other coding or non-coding transcripts. However, this needs to be further integrated in a regulatory network that acts in conjunction with other markers that affect the patients’ prognosis or response to therapy.Electronic supplementary materialThe online version of this article (10.1186/s13046-018-0920-2) contains supplementary material, which is available to authorized users.

New and known arylidene-hydrazinyl-thiazole derivatives have been synthesized by a convenient Hantzsch condensation. All compounds were evaluated for their in vitro cytotoxicity on two carcinoma cell lines, MDA-MB231 and HeLa. Significant antiproliferative activity for 2-(2-benzyliden-hydrazinyl)-4-methylthiazole on both MDA-MB-231 (IC50: 3.92 µg/mL) and HeLa (IC50: 11.4 µg/mL) cell lines, and for 2-[2-(4-methoxybenzylidene) hydrazinyl]-4-phenylthiazole on HeLa (IC50: 11.1 µg/mL) cell line is reported. Electrophoresis experiments showed no plasmid DNA (pTZ57R) cleavage in the presence of the investigated thiazoles.

Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine involved in the promotion and progression of cancer, including triple negative breast cancer cells. Thus, there is significant interest in understanding the molecular signaling pathways that connect TNF-α with the survival of tumor cells. In our experiments, we used as an in vitro model for triple negative breast cancer the cell line Hs578T. The purpose of this study is to determine the gene expression profiling of apoptotic signaling networks after blocking TNF-α formation by using specially designed siRNA molecules to target TNF-α messenger RNA. Knockdown of TNF-α gene was associated with cell proliferation inhibition and apoptosis, as observed by monitoring the cell index using the xCELLigence RTCA System and flow cytometry. PCR array technology was used to examine the transcript levels of 84 genes involved in apoptosis. 15 genes were found to be relevant after comparing the treated group with the untreated one of which 3 were down-regulated and 12 up-regulated. The down-regulated genes are all involved in cell survival, whereas the up-regulated ones are involved in and interact with pro-apoptotic pathways. The results described here indicate that the direct target of TNF-α in the Hs578T breast cancer cell line increases the level of certain pro-apoptotic factors that modulate different cellular networks that direct the cells towards death.

p53 protein is probably the best known tumor suppressor. Earlier reports proved that human breast cancer cells expressing mutant p53 displayed resistance to apoptosis. This study is intended to investigate, the potential applications of RNA interference (RNAi) to block p53 expression, as well as its subsequent effect on cell growth, apoptosis and migration on a triple negative human breast cancer cell line (Hs578T). p53siRNA significantly reduced cell index (CI) compared to the control and we observed an inhibition of cellular migration in the interval of time between 0 and 30 h, as shown in the data obtained by dynamic evaluation using the xCELLigence System. Also, by using PCR-array technology, a panel of 84 key genes involved in apoptosis was investigated. Our studies indicate that the knockdown of p53 expression by siRNA modulates several genes involved in cell death pathways and apoptosis, showing statistically significant gene expression differences for 22 genes, from which 18 were upregulated and 4 were downregulated. The present research also emphasizes the important role of BCL-2 pro-apoptotic family of genes (Bim, Bak, and Bax) in activating apoptosis and reducing cell proliferation by p53siRNA treatment. Death receptors cooperate with BCL-2 pro-apoptotic genes in reducing cell proliferation. The limited success may be due to the activation of the antiapoptotic gene Mcl-1, and it may be associated with the resistance of triple negative breast cancer cells to cancer treatment. Thus, targeting p53siRNA pathways using siRNA may serve as a promising therapeutic strategy for the treatment of breast cancers.