miR-455-5p enhances 5-fluorouracil sensitivity in colorectal cancer cells by targeting PIK3R1 and DEPDC1.

Our previous study has demonstrated that miR-455-5p was a tumor suppressor in colorectal cancer (CRC). This study aimed to investigate the role of miR-455-5p in 5-fluorouracil (5-Fu) in CRC. The expression of miR-455-5p, PIK3R1, and DEPDC1 was analyzed in HT-29 cells after treatment with different concentrations (0, 0.5, 2.5, and 12.5 µM) of 5-Fu. The effects of miR-455-5p on cell proliferation and apoptosis were analyzed by CCK-8 and flow cytometry. PIK3R1 and DEPDC1 were overexpressed to measure the mechanism of miR-455-5p on 5-Fu sensitivity. And the direct binding between miR-455-5p and DEPDC1 was detected by a dual-luciferase reporter assay. We found that miR-455-5p decreased, while PIK3R1 and DEPDC1 increased after 5-Fu treatment. miR-455-5p mimic significantly suppressed cell viability and elevated cell apoptosis in 5-Fu-treated HT-29 cells, whereas miR-455-5p inhibitor showed the opposite effects. Overexpression of PIK3R1 and DEPDC1 could attenuate the effects of miR-455-5p mimic on the viability and apoptosis of 5-Fu-treated cells. miR-455-5p could directly bind to DEPDC1 in HT-29 cells. In conclusion, miR-455-5p enhanced 5-Fu sensitivity by targeting PIK3R1 and DEPDC1 in CRC. This study provides a novel role of miR-455-5p in CRC and restoring miR-455-5p might be a therapeutic strategy to enhance chemosensitivity to 5-Fu.

Comparison of efficacy between sequential ventilation and conventional invasive mechanical ventilation in the treatment of pulmonary hypertension complicated with respiratory failure.

OBJECTIVE: Pulmonary hypertension (PAH) is a serious progressive and fatal pulmonary disease characterized by elevated pulmonary artery pressure. Mechanical sequential ventilation has been gradually applied in the treatment of patients with PAH complicated with RF, which can effectively reduce the incidence of VAP and better promote the recovery of respiratory function. This study is aimed to determine the efficacy of sequential ventilation and conventional invasive mechanical ventilation in the treatment of pulmonary hypertension (PAH) complicated with respiratory failure (RF). METHODS: A total of 198 patients with both PAH and RF admitted to our hospital were enrolled. Among them, 102 patients were treated with sequential ventilation as a study group (stu group), and 96 patients were treated with conventional invasive mechanical ventilation as a control group (con group). Then the two groups were compared in efficacy and related indexes before and after treatment. RESULTS: The stu group experienced significantly shorter invasive ventilation time, total mechanical ventilation time, and hospitalization time than the con group (all P<0.05), and showed a significantly lower complication rate than the con group (P<0.05). The reintubation rate, weaning failure rate, and ventilator-associated pneumonia (VAP) rate of the stu group were all significantly lower than those of the con group (all P<0.05), and the stu group showed significantly higher pondus hydrogenii (pH) and arterial partial pressure of oxygen (PaO2) and significantly lower arterial carbondioxide partial pressure (PaCO2) than the con group after treatment (all P<0.05). Additionally, after treatment, the level of brain natriuretic peptide (BNP) and pulmonary artery pressure in both groups declined significantly (P<0.05), and the decline of them in the stu group was more significant than that in the con group (P<0.05). Moreover, after treatment, endothelin (ET) and angiotensin II (Ang II) in both groups declined significantly, and the decline of them in the stu group was also more significant than that in the con group (P<0.05). CONCLUSION: Compared with conventional invasive mechanical ventilation, sequential ventilation can effectively minimize the treatment time of patients with PAH complicated with RF, reduce the incidences of adverse events and complications in them, and significantly improve the blood gas analysis indexes and BNP in them, so it is worthy of clinical promotion.

A-kinase interacting protein 1 as a potential biomarker of advanced tumor features and increased recurrence risk in papillary thyroid carcinoma patients.

BACKGROUND: This study aimed to detect the expression of A-kinase interacting protein 1 (AKIP1) and explore its correlation with clinicopathological features and clinical outcomes in papillary thyroid carcinoma (PTC) patients. METHODS: A total of 245 PTC patients treated by lobectomy or thyroidectomy were analyzed in this retrospective study. AKIP1 expression in tumor and adjacent tissue (from Specimen Room of our hospital) was detected by immunohistochemical (IHC) assay and then categorized as four grades: AKIP1 low (IHC score ≤3), high+ (IHC score 4-6), high++ (IHC score 7-9), and high+++ (IHC score 10-12). RESULTS: A-kinase interacting protein 1 low, high+, high++, and high+++ expression was 101 (41.2%), 101 (41.2%), 32 (13.1%), and 11 (4.5%) in tumor tissues, while was 173 (70.6%), 61 (24.9%), 9 (3.7%), and 2 (0.8%) in adjacent tissues. Further comparison analysis showed increased grade of AKIP1 expression in tumor tissues compared to adjacent tissue. Meanwhile, increased grade of tumor AKIP1 expression was correlated with larger tumor size, extrathyroidal invasion, increased pT stage, and higher pTNM stage. For prognosis, increased grade of tumor AKIP1 expression was correlated with shorter disease-free survival (DFS), while was not correlated with overall survival (OS). Forward stepwise multivariate Cox's regression revealed that higher tumor AKIP1 was an independent factor predicting worse DFS, but not OS. CONCLUSION: AKIP1 is upregulated in tumor tissue, and increased tumor AKIP1 expression correlates with advanced tumor features and increased recurrence risk in PTC patients, which suggest that AKIP1 severs as a potential marker for effective supervision of PTC progression.

Circular RNA CircPRMT5 Accelerates Proliferation and Invasion of Papillary Thyroid Cancer Through Regulation of miR-30c/E2F3 Axis.

BACKGROUND: The role of circular RNA (circRNA) in papillary thyroid cancer (PTC) is largely unknown. This study aims to determine the function and mechanism of circPRMT5 in the regulation of PTC development. METHODS: PTC tissues and cell lines were used to determine circPRMT5 expression via quantitative real-time polymerase chain reaction. Small interfering RNA (siRNA) was utilized to knock down circPRMT5. Proliferation was analyzed through CCK8 and colony formation assays. Transwell assay was performed to determine cell migration and invasion. Luciferase assay and RIP assay were carried out to analyze the interaction between circPRMT5 and miR-30c. RESULTS: CircPRMT5 expression was upregulated in PTC tissues and cell lines. And circPRMT5 level was positively linked with advanced stage and lymph node metastasis. CircPRMT5 knockdown inhibited proliferation, migration and invasion while inducing apoptosis. CircPRMT5 worked as a competing endogenous RNA for miR-30c. By inhibiting miR-30c, circPRMT5 promoted the expression of E2F3. CONCLUSION: Our findings demonstrate that circPRMT5 acts as an oncogenic circRNA to promote PTC progression via regulating miR-30c/E2F3 axis.

LncRNA PART1 facilitates the malignant progression of colorectal cancer via miR-150-5p/LRG1 axis.

Study has shown that long noncoding RNA (lncRNA) prostate androgen-regulated transcript 1 (PART1) was elevated in colorectal cancer tissues and cells, and the proliferation and metastasis of colorectal cancer cells were reduced after its downregulation. The tumor-suppressive role of microRNA-150-5p (miR-150-5p) has been shown in colorectal cancer. In this study, the association between PART1 and miR-150-5p in colorectal cancer was analyzed. Results revealed an increase of PART1, but a decrease of miR-150-5p in 56 colorectal cancer tissues. And there was a strong negative correlation between levels of PART1 and miR-150-5p in these cancer samples. Also, compared with 10 healthy controls, the level of PART1 was increased, whereas miR-150-5p expression was diminished in the serum of 10 colorectal cancer patients. Cell proliferation and migration, along with epithelial-mesenchymal transition, was promoted by PART1 overexpression. However, this lncRNA mitigated apoptosis of colorectal cancer cells. Whereas miR-150-5p mimic abrogated these effects caused by PART1 overexpression. The influences of PART1 knockdown on the above malignant characteristics of colorectal cancer cells were contrary to its overexpression. miR-150-5p inhibitor ablated the effects induced by PART1 knockdown. In xenograft mouse models, silencing of PART1 decreased tumor volume and weight. Our data supported that lncRNA PART1 may regulate leucine-rich α-2-glycoprotein-1 (LRG1) expression through a competing interaction mechanism that hindering miR-150-5p function. In conclusion, PART1 facilitates the malignant progression of colorectal cancer via miR-150-5p/LRG1 pathway. The study further clarified the molecular mechanism of PART1 in colorectal cancer. This study may provide a new approach to diagnose and treat colorectal cancer.

Expression profile and biological function of miR-455-5p in colorectal carcinoma.

Underexpression of microRNA-455-5p (miR-455-5p) in medullary thyroid carcinoma, melanoma, gastric cancer and additional cancer types has been reported, which may be associated with carcinoma development. The present study aimed to evaluate the expression profile and biological role of miR-455-5p in colorectal carcinoma. Carcinoma tissues and adjacent tissue specimens from 40 patients with colorectal cancer were randomly collected. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis was conducted to detect the expression levels of miR-455-5p in colorectal carcinoma and adjacent normal tissues. The biological effects of miR-455-5p on selected colorectal cancer cells were assessed using bromodeoxyuridine assays, wound healing migration assays and flow cytometry. Bioinformatics analysis was implemented to predict the potential target genes of miR-455-5p in colorectal cancer. The expression levels of target genes were further validated by RT-qPCR and western blot analysis of the mRNA and protein levels. The results of the experiments demonstrated that miR-455-5p expression was downregulated in colorectal cancer tissues compared with adjacent normal tissues. In colorectal cancer cells (SW-480, HT-29 and HCT-116), miR-455-5p was observed to inhibit cell proliferation and migration while promoting cell apoptosis. Bioinformatics analysis predicted that the oncogene phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) was one of the top ranked target genes of miR-455-5p in colorectal cancer cells. This association was validated by RT-qPCR and western blotting. In vivo studies revealed that the expression level of miR-455-5p was significantly downregulated in human colorectal cancer. Further in vitro studies suggested that miR-455-5p may prevent the development of colorectal cancer by downregulating the oncogene PIK3R1. It was concluded that miR-455-5p may target and downregulate PIK3R1 in colorectal cancer.

MicroRNA-10a suppresses breast cancer progression via PI3K/Akt/mTOR pathway.

Previous studies have demonstrated that microRNA-10a (miR-10a) regulates various opposing biological functions in breast cancer. The aim of the present study was to investigate the exact functions of miR-10a in the pathogenesis of breast cancer. miR-10a expression was initially detected in two human breast cancer cell lines, MCF-7 and MDA-MB-231 and a normal human mammary epithelial cell line MCF-10A. The proliferation, migration and apoptosis of breast cancer cells were analyzed using MTT assays, Transwell assays and flow cytometry, respectively, following transfection of MCF-7 and MDA-MB-231 cells with an miR-10a mimic or anti-miR-10a. The expression of phosphorylated (p-)protein kinase B (Akt), p-mammalian target of rapamycin (p-mTOR), p-ribosomal protein S6 kinase ß-1 (p-p70S6K), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA), Cytochrome C (Cyt C), B-cell lymphoma 2 (Bcl-2), BCL-2 associated X, apoptosis regulator (Bax), and cleaved caspase-3 were analyzed by western blotting. The migration of MCF-7 cells pretreated with an mTOR inhibitor CCI-779, was detected using a Transwell assay. Relative miR-10a expression was significantly elevated in MDA-MB-231 breast cancer cells and was at its highest levels in MCF-7 cells. Transfection with the miR-10a mimic significantly inhibited proliferation and migration, and promoted the apoptosis of breast cancer cells. Furthermore, upregulation of miR-10a markedly suppressed the levels of p-Akt, p-mTOR, p-p70S6K, and PIK3CA, and increased the expression of Cyt C, cleaved caspase-3, and the ratio of Bax/Bcl-2. Anti-miR-10a had the opposite effects. In addition, CCI-779 reversed the effect of anti-miR-10a on the migration of MCF-7 cells in a dose-dependent manner. In conclusion, miR-10a is downregulated in high aggressive breast cancer cells. miR-10a inhibited the proliferation and migration, and promoted apoptosis of breast cancer cells via phosphoinositide/Akt/mTOR signaling, and the mitochondrial apoptotic pathway.