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 ... -  《-》

Reduced Proline-Rich Tyrosine Kinase 2 Promotes Tumor Metastasis by Activating Epithelial-Mesenchymal Transition in Colorectal Cancer.

Proline-rich tyrosine kinase 2 (PYK2) is involved in the occurrence, proliferation, migration, and invasion of various tumors. However, few studies have reported the role of PYK2 in colorectal cancer (CRC). To explore the effects of PYK2 on CRC metastasis and elucidate the detailed molecular mechanisms involved. The expression and prognosis value of PYK2 in CRC prognosis were analyzed using data from The Cancer Genome Atlas (TCGA). PYK2 was knocked down or overexpressed in human CRC cell line, HCT116. Cell proliferation, migration, invasion, and cycle changes were analyzed using CCK-8, Transwell, and flow cytometry assays. Western blotting and quantitative real-time PCR were performed to detect the mRNA and protein levels of cell proliferation and epithelial-mesenchymal transition (EMT) indicators. Fluorescence staining was performed to examine the cytoskeleton. Lower expression of PYK2 was observed in CRC tissues and associated with poor prognosis and metastasis in patients with CRC in TCGA database. PYK2 knockdown significantly induced the migration and invasion of CRC cells but did not affect cell proliferation or cycle. Immunofluorescence staining of phalloidin showed that the downregulation of PYK2 increased the cytoskeleton in CRC cells. Moreover, low expression of PYK2 induced the downregulation of E-cadherin and upregulation of snail and vimentin by activating Wnt/β-catenin signaling, thus promoting EMT in CRC cells. Low PYK2 expression was found in tumor tissues, especially metastases, and significantly correlated with patient prognosis. Moreover, decreased PYK2 induces EMT by activating Wnt/β-catenin signaling, which is the potential mechanism of CRC metastasis. Regulating the expression of PYK2 to suppress tumor cell metastasis may represent a promising therapeutic strategy for metastatic CRC.

Wu F ，Zhang K ，Song Z ，Zhou Q ，Sun H ，Tan Z ，Huang Z ，Wang F ，Wang Z ，Yang R ，Huang Y ... -  《-》

Hypoxic BMSC-derived exosomal miR-210-3p promotes progression of triple-negative breast cancer cells via NFIX-Wnt/β-catenin signaling axis.

Bone marrow mesenchymal stem cells (BMSCs) are a crucial component of the tumor microenvironment (TME), with hypoxic conditions promoting their migration to tumors. Exosomes play a vital role in cell-to-cell communication within the TME. Hypoxic TME have a great impact on the release, uptake and biofunctions of exosomes. This study aims to elucidate the communication between BMSC-derived exosomal miRNA and triple-negative breast cancer (TNBC) in a hypoxic environment. Exosomes were isolated via ultracentrifugation and identified using scanning electron microscopy (SEM), nanoparticle tracking analysis (NTA) and western blot. A range of bioinformatics approaches were used to screen exosomal miRNAs and the target mRNAs of miRNAs and predict the possible signaling pathways. Expression levels of genes and proteins were assessed by quantitative real-time PCR and western blot. Cell proliferation, apoptosis, migration and invasion were analyzed using CCK-8 assay, EDU assay, transwell migration, wound healing assay and invasion assay, respectively. Dual luciferase reporter gene assay was conducted to confirm the binding between miRNAs and the target mRNAs. The impact of hypoxic BMSC-derived exosomal miRNA on TNBC progression in vivo was evaluated using tumor xenograft nude mouse models. Furthermore, the impact of patients' serum exosomal miRNA on TNBC was implemented. Exosomes derived from hypoxic BMSCs promotes the proliferation, migration, invasion and epithelial-mesenchymal transition of TNBC and suppresses the apoptosis of TNBC. The expression of miR-210-3p in BMSC-derived exosomes is markedly elevated in hypoxic conditions. Exosome-mediated transfer of miR-210-3p from hypoxic BMSCs to TNBC targets NFIX and activates Wnt/β-Catenin signaling in TNBC. Deletion of miR-210-3p in hypoxic BMSC-derived exosomes attenuates TNBC in vivo. Additionally, human exosomal miR-210-3p from the serum of TNBC patients promotes TNBC progression. Moreover, we notably observed a marked downregulation of NFIX expression levels in cancerous tissues compared to paracancerous tissues. Hypoxic BMSC-derived exosomal miR-210-3p promotes TNBC progression via NFIX-Wnt/β-catenin signaling axis.

Wang M ，Zheng Y ，Hao Q ，Mao G ，Dai Z ，Zhai Z ，Lin S ，Liang B ，Kang H ，Ma X ... -  《Journal of Translational Medicine》

Erratum: Eyestalk Ablation to Increase Ovarian Maturation in Mud Crabs.

《Jove-Journal of Visualized Experiments》

BVES-AS1 suppresses the colorectal cancer progression via the miR-1269a/b-SVEP1-PI3K/AKT axis.

Yang J ，Deng Q ，Chen Z ，Chen Y ，Fu Z ... -  《Advances in Clinical and Experimental Medicine》