Long non-coding RNA breast cancer-associated transcript 54 sponges microRNA-1269b to suppress the proliferation of hemangioma-derived endothelial cells

Long non-coding RNA (lncRNA) breast cancer-associated transcript 54 (BRCAT54) and microRNA-1269b (miR-1269b) are two critical ncRNAs in cancer biology, while their roles in hemangioma are unknown. Our preliminary sequencing data revealed their altered expression in hemangioma and predicted they could interact with each other. This study was therefore carried out to investigate the roles of BRCAT54 and miR-1269b in hemangioma, with a focus on their interaction. In this study, hemangioma samples donated by 20 infantile hemangioma patients at proliferating-phase and 20 infantile hemangioma patients at involuting-phase were used. The expression of BRCAT54 and miR-1269b in hemangioma samples, as well as hemangioma-derived endothelial cells (HDECs) and human umbilical vein endothelial cells (HUVECs) were detected by RT-qPCR. IntaRNA 2.0 was applied to predict the interaction between BRCAT54 and miR-1269b, which was then confirmed by RNA-RNA pulldown assay. Accumulation of BRCAT54 in the subcellular location of HDECs was detected by subcellular fractionation assay. The role of BRCAT54 and miR-1269b in cell proliferation has been explored by the BrdU assay. Compared to proliferating-phase tissues, involuting-phase tissues exhibited decreased expression levels of BRCAT54 and increased expression levels of miR-1269b. HDECs had decreased expression levels of BRCAT54 and increased expression levels of miR-1269b compared to that of HUVECs. In HDECs, BRCAT54, which was detected in both nuclear and cytoplasm fractions, directly interacted with miR-1269b. BRCAT54 and miR-1269b did not affect the expression of each other, while BRCAT54 suppressed the role of miR-1269b in enhancing the proliferation of HDECs. BRCAT54 may sponge miR-1269b to suppress the proliferation of HDECs.

MicroRNA-1269b inhibits gastric cancer development through regulating methyltransferase-like 3 (METTL3)

The dysregulation of microRNAs (miRNAs) expression is relevant to the progression of many tumors. As reported, the abnormal expression of miR-1269b is pivotal in certain cancers’ progression. This work was designed to study the role and hidden mechanism of miR-1269b in gastric cancer (GC) progression. In this work, we proved that miR-1269b was lowly expressed in GC tissues and cell lines, which was associated with larger tumor size and lymph node metastasis. MiR-1269b overexpression repressed the multiplication, migration and invasion of GC cells while miR-1269b inhibition had the opposite effects. Methyltransferase-like 3 (METTL3) was identified as the direct target of miR-1269b in GC cells, and its overexpression reversed the inhibitory effect of transfection of miR-1269b mimics on GC cell viability, migration and invasion. On all accounts, these data indicated that miR-1269b inhibits GC progression via targeting METTL3.

miR-1269b Drives Cisplatin Resistance of Human Non-Small Cell Lung Cancer via Modulating the PTEN/PI3K/AKT Signaling Pathway

Background

MiRNAs have been reported to induce certain drug resistance in multiple solid tumors via various mechanisms. Our study aimed to investigate whether miRNA-1269b was involved in the chemoresistance and the progression of non-small cell lung cancer (NSCLC).

Methods

MTT and colony formation assay were conducted to determine cell proliferation and cell apoptosis was analyzed by flow cytometry with annexin V/PI. Luciferase reporter assay was performed to validate miRNA-targeting sequences. The function of miR-1269b in cisplatin-resistant was evaluated in vivo in a mouse tumor model.

Results

We found that miR-1269b expression was up-regulated in cisplatin-resistant NSCLC specimens and NSCLC cell lines, which resulted in the promotion of chemoresistance and tumorigenicity. miR-1269b overexpression enhanced drug resistance and promoted cell proliferation in vitro and tumor growth in vivo, with reduced apoptosis rate of A549 cells inin vitro cell culture. Mechanistically, we identified PTEN as the direct target of miR-1269b, and the PTEN level was negatively correlated with miR-1269b in NSCLC specimens. Further study demonstrated that miR-1269b targeted PTEN to modulate PI3K/AKT signaling pathway.

Conclusion

In conclusion, these findings suggest that the miR-1269b/PTEN/PI3K/AKT-mediated network might promote cisplatin resistance in NSCLC, and that miR-1269b can be a potential therapeutic target for chemoresistance in NSCLC patients.

Genetic variants in microRNA-146a (C>G) and microRNA-1269b (G>C) are associated with the decreased risk of oral premalignant lesions, oral cancer, and pharyngeal cancer

OBJECTIVE

To investigate the relationships between two single-nucleotide polymorphisms at miR-146a C>G (rs2910164) and miR-1269b G>C (rs7210937) and the risk of developing oral premalignant lesions (OPLs), oral squamous cell carcinoma (OSCC), pharyngeal SCC (PSCC), and oral and pharyngeal SCC (OPSCC).

DESIGN

Genotyping of miR-146a C>G and miR-1269b G>C was performed in two case-control studies using the TaqMan assay. A total of 197 healthy control subjects, 241 OPLs patients, and 188 OPSCC patients who habitually chewed betel quid (BQ) were recruited into one case-control study. Additionally, 668 cancer-free control subjects and 658 OPSCC patients were recruited into the other case-control study.

RESULTS

The G/G genotype at miR-146a C>G was associated with the decreased risk of OSCC [adjusted odds ratio (AOR)=0.66, P=0.040], PSCC (AOR=0.42, P=0.013), and OPSCC (AOR=0.63, P=0.020). Additionally, the C allelic type and C/C genotype at miR-1269b G>C decreased the risk of BQ-related oral leukoplakia (C vs. G: AOR=0.68, P=0.012;C/C vs. G/G: AOR=0.43, P=0.009), BQ-related OPLs (C vs. G: AOR=0.69, P=0.008;C/C vs. G/G: AOR=0.44, P=0.005), and BQ-related OPSCC (C vs. G: AOR=0.65, P=0.003;C/C vs. G/G: AOR=0.47, P=0.011). In OPSCC patients, the G/G genotype of miR-146a was correlated with well-differentiated cells (P=0.041), and the G/C and C/C genotypes of miR-1269b were correlated with the absence of lymph node involvement (P=0.031), especially in OSCC patients (P=0.038 and P=0.007, respectively).

CONCLUSION

The genetic variants of miR-146a and miR-1269b are biomarkers against the development of OPLs and OPSCC.

HBx-induced MiR-1269b in NF-κB dependent manner upregulates cell division cycle 40 homolog (CDC40) to promote proliferation and migration in hepatoma cells

BACKGROUND

Occurrence and progression of hepatocellular carcinoma (HCC) are associated with hepatitis B virus (HBV) infection. miR-1269b is up-regulated in HCC cells and tissues. However, the regulation of miR-1269b expression by HBV and the mechanism underlying the oncogenic activity of miR-1269b in HCC are unclear.

METHODS

Reverse transcription quantitative PCR (RT-qPCR) was used to measure the expression of miR-1269b and target genes in HCC tissues and cell lines. Western blot analysis was used to assess the expression of miR-1269b target genes and related proteins. Using luciferase reporter assays and EMSA, we identified the factors regulating the transcriptional level of miR-1269b. Colony formation, flow cytometry and cell migration assays were performed to evaluate the phenotypic changes caused by miR-1269b and its target in HCC cells.

RESULTS

We demonstrated that the expression levels of pre-miR-1269b and miR-1269b in HBV-positive HepG2.2.15 cells were dramatically increased compared with HBV-negative HepG2 cells. HBx was shown to facilitate translocation of NF-κB from the cytoplasm to the nucleus, and NF-κB binds to the promoter of miR-1269b to enhance its transcription. miR-1269b targets and up-regulates CDC40, a cell division cycle 40 homolog. CDC40 increases cell cycle progression, cell proliferation and migration. Rescue experiment indicated that CDC40 promotes malignancy induced by miR-1269b in HCC cells.

CONCLUSION

We found that HBx activates NF-κB to promote the expression of miR1269b, which augments CDC40 expression, contributing to malignancy in HCC. Our findings provide insights into the mechanisms underlying HBV-induced hepatocarcinogenesis.