MiR-21-5p knockdown inhibits epithelial to mesenchymal transition in A549 lung adenocarcinoma cells by upregulating RhoB.

MiR-21-5p is a highly expressed microRNA that plays an important role in various cancer-promoting processes, including anchorage-independent growth, invasion, migration metastasis, and drug resistance in lung cancer. Studies indicate that miR-21-5p may contribute to these processes by promoting epithelial-mesenchymal transition (EMT). Ras homolog gene family member B (RhoB), a gene downregulated by miR-21-5p, has also been linked to EMT in lung cancer. However, the role of the miR-21-5p/RhoB axis in EMT regulation in lung adenocarcinoma remains unclear. In this study, we aimed to investigate the regulatory role of the miR-21-5p/RhoB axis in EMT and related in vitro functional characteristics such as migration, invasion, cisplatin resistance, and the formation of tumor spheroids. A549 cells were transfected with the miR-21-5p inhibitor, RhoB siRNA, and their corresponding negative controls. Wound healing, transwell invasion, Methyl thiazole tetrazolium (MTT), and sphere formation assays were also performed to evaluate the migration, invasion, cisplatin resistance, and anchorage-independent growth of A549 cells. RT-qPCR was used to determine the mRNA expression levels of EMT markers. MiR-21-5p knockdown inhibited migration, invasion, cisplatin resistance, and sphere formation while upregulating E-cadherin and downregulating Slug. Furthermore, RhoB silencing restored EMT and related in vitro functional characteristics in A549 cells. Knockdown of miR-21-5p inhibits EMT and related in vitro functional characteristics by upregulating RhoB, suggesting that miR-21-5p may promote EMT through downregulation of RhoB.

Khair HHA ，Karagöz ID 《-》

The miR-1269a/PCDHGA9/CXCR4/β-catenin pathway promotes colorectal cancer invasion and metastasis.

Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cause of cancer-related death. This research focuses on investigating the impact and underlying molecular mechanisms of protocadherin gamma subfamily A, 9 (PCDHGA9) on the invasion and metastasis of CRC, aiming to identify more precise molecular markers for the diagnosis and prognosis of CRC. PCDHGA9 expression was detected using quantitative real-time quantitative polymerase chain reaction (RT-qPCR) in 63 pairs of colorectal cancer tissues. Differential gene expression from high-throughput sequencing was analyzed using ingenuity pathway analysis (IPA) to explore the biological functions of PCDHGA9 and its potential regulated genes. Bioinformatics tools were employed to explore potential upstream regulatory microRNAs of PCDHGA9. Dual-luciferase assays were performed to demonstrate the regulation between PCDHGA9 and miR-1269a. Protein mass spectrometry suggested an interaction between PCDHGA9 and HOXA1. JASPAR predicted that HOXA1 may act as a transcription factor of CXCR4. Coimmunoprecipitation, dual-luciferase assays, and nuclear-cytoplasmic fractionation experiments confirmed the molecular mechanism involving PCDHGA9, CXCR4, HOXA1, and β-catenin. Transwell, wound healing, and western blot assays were conducted to confirm the impact of PCDHGA9, miR-1269a, and CXCR4 on the invasion, metastasis, and epithelial-mesenchymal transition (EMT) functions of CRC cells in in vitro experiments. A whole-body fluorescence imaging system was used to evaluate the combined impact of miR-1269a and PCDHGA9 on the invasion and metastasis of CRC in in vivo experiments. The expression of PCDHGA9 was found to be lower in CRC tissues compared with their corresponding adjacent tissues. Low expression of PCDHGA9 potentially correlated with worse prognosis and increased chances of invasion and metastasis in CRC. miR-1269a was highly expressed in CRC tissues and acted as a negative regulator for PCDHGA9, promoting invasion, migration, and EMT of CRC cells. PCDHGA9's interaction with HOXA1 downregulated CXCR4, a transcription factor, leading to accumulation of β-catenin and further promoting invasion, migration, and EMT of CRC cells. PCDHGA9, acting as a tumor suppressor, is downregulated by miR-1269a. The low level of PCDHGA9 activates the Wnt/β-catenin pathway by releasing its interaction with HOXA1, promoting the expression of CXCR4, and causing invasion, migration, and EMT in CRC.

Mei H ，Luo Q ，Weng J ，Hao J ，Cai J ，Zhou R ，Bian C ，Ye Y ，Luo S ，Wen Y ... -  《-》

Exosomal miR-20b-5p Induces EMT and Enhances Progression in Non-Small Cell Lung Cancer Via TGFBR2 Downregulation.

The mechanism by which specific miRNAs in NSCLC exosomes regulate NSCLC progression remains unclear. First, exosomes were isolated and identified. Exosomes were labeled with PKH26 for cell tracking studies. Subsequently, BEAS-2B cells and BEAS-2B cell exosomes were transfected with miR-20b-5p mimics or miR-20b-5p inhibitors, and cell proliferation was measured by EdU and CCK-8. cell migration and invasion were detected by wound healing tests and Transwell. The potential target of miR-20b-5p was predicted and verified by luciferase assay. Relative expression levels of miR-20b-5p and TGFBR2 were detected by qRT-PCR. Protein expression level was detected by Western blot. In addition, A549 cell exosomes were injected into mice through the tail vein and the pathological changes of lung tissue were detected by HE staining. Expression levels of E-cadherin and Vimentin in lung tissues were detected by immunohistochemistry. Our results also showed that high levels of miR-20b-5p in exosomes generated from NSCLC cells conceivably enter the cytoplasm of their own cells and by downregulating TGFBR2, accelerate NSCLC invasion, migration and EMT while promoting NSCLC cell proliferation. Exosome analysis using clinical plasma specimens revealed that miR-20b-5p expression was considerably improved in exosomes from NSCLC patients compared with those from healthy controls. In vitro and in vivo, exosomes with high levels of miR-20b-5p were linked to the progression of NSCLC. Our data suggest that exosomes with high levels of miR-20b-5p can increase development and metastasis of NSCLC cells by downregulating TGFBR2, which would serve as a predictive and diagnostic marker for NSCLC.

Ma H ，Jiang B ，Ren Q ，Sun Y ，Wang M ，Xia S ，Wang D ，Zhang W ... -  《-》

MALAT1 promotes epithelial-mesenchymal transition of pancreatic cancer cells through the miR-141-5p-TGF-ß-TGFBR1/TGFBR2 axis.

Li Z ，Yue C ，Hou S ，Huang X ，Wang Z ，Hu W ，Lu H ... -  《-》

LncRNA DLX6-AS1 Contributes to Epithelial-Mesenchymal Transition and Cisplatin Resistance in Triple-negative Breast Cancer via Modulating Mir-199b-5p/Paxillin Axis.

Du C ，Wang Y ，Zhang Y ，Zhang J ，Zhang L ，Li J ... -  《-》