MicroRNA-206 functions as a tumor suppressor in colorectal cancer by targeting FMNL2.

Ren XL ，He GY ，Li XM ，Men H ，Yi LZ ，Lu GF ，Xin SN ，Wu PX ，Li YL ，Liao WT ，Ding YQ ，Liang L ... -  《-》

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 ... -  《-》

Circular RNA (circ)_0053277 Contributes to Colorectal Cancer Cell Growth, Angiogenesis, Metastasis and Glycolysis.

Circular RNAs (circRNAs) have been found to be abnormally expressed in many cancers, including colorectal cancer (CRC). Circ_0053277 has been found to mediate CRC malignant processes and may be a key regulator for CRC progression. Therefore, its role and potential molecular mechanism in CRC process deserve further investigation. Quantitative real-time PCR was used to detect the expression levels of circ_0053277, microRNA-520 h (miR-520 h) and hexokinase 1 (HK1). Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine assay, flow cytometry, wound healing assay, transwell assay, and tube formation assay were used to detect CRC cell proliferation, apoptosis, migration, invasion, and angiogenesis. The protein levels of apoptosis-related markers and HK1 were detected by western blot. The relationship between circ_0053277 and miR-520 h or miR-520 h and HK1 in CRC cells was verified by dual-luciferase reporter assay, RNA immunoprecipitation assay and RNA pull-down assay. Cell glycolysis was assessed by detecting glucose uptake and lactate production. The effect of silenced circ_0053277 on CRC tumor growth was evaluated by xenograft model in vivo. Our study found that circ_0053277 expression was elevated in CRC tissues and cells. Moreover, circ_0053277 knockdown suppressed CRC cell proliferation, angiogenesis, migration and invasion, while promoting apoptosis. In terms of mechanism, circ_0053277 sponged miR-520 h, and HK1 was the target of miR-520 h. Meanwhile, miR-520 h inhibitor reversed the inhibitory effect of circ_0053277 silencing on CRC cell progression, and HK1 overexpression also overturned the suppressive effect of miR-520 h on CRC cell growth, angiogenesis and metastasis. Moreover, circ_0053277 knockdown inhibited the glycolysis of CRC cells by regulating miR-520 h/HK1 pathway. In addition, knockdown of circ_0053277 reduced CRC tumor growth in vivo. Circ_0053277 promoted CRC cell growth, angiogenesis, metastasis and glycolysis by miR-520 h/HK1 pathway, confirming that circ_0053277 might be a potential clinical target for CRC treatment.

Zhuang J ，Song W ，Li M ，Kang D ，Cheng K ... -  《-》

Circ_0006174 Upregulates IGF1R to Enhance Radioresistance and Tumorigenesis in Colorectal Cancer via miR-940 Suppression.

Colorectal cancer (CRC) is one of the most common malignancies all over the world. Increasing evidence has revealed that circular RNAs (circRNAs) are involved in the progression of CRC. In this study, we aimed to investigate the role and underlying mechanism of circ_0006174 in the development and radiosensitivity of CRC. Circ_0006174, microRNA-940 (miR-940), and insulin-like growth factor 1 receptor (IGF1R) expression levels were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR). The radiosensitivity of cells also was assessed using colony formation assay. Besides, cell proliferation, apoptosis, migration, and invasion were detected by cell counting kit-8 (CCK-8), flow cytometry, and transwell assays. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to verify the relationship between miR-940 and circ_0006174 or IGF1R. IGF1R protein level was examined using western blot. A xenograft tumor model was used to verify the function of circ_0006174 in CRC tumor growth in vivo. Circ_0006174 and IGF1R levels were elevated and miR-940 expression was decreased in CRC tissues and cells. Circ_0006174 knockdown enhanced the radiosensitivity of CRC cells by regulating cell proliferation, apoptosis, migration, and invasion in vitro. In mechanism, circ_0006174 served as a sponge for miR-940 to upregulate IGF1R expression. Moreover, circ_0006174 silencing suppressed CRC growth in vivo. Circ_0006174 boosts radioresistance of CRC cells at least partly through upregulating IGF1R expression by sponging miR-940, providing a novel theoretical basis for CRC therapy.

Zhang X ，Fang F ，Zhang J ，Zhang S ，Li H ，Li B ，Zhong Y ，Zhen P ... -  《-》

circEIF3I Promotes Colorectal Cancer Metastasis by Regulating the miR-328-3p/NCAPH Axis.

Colorectal cancer (CRC) is the most common gastrointestinal malignancy, with its recurrence and metastasis significantly affecting patient survival. Circular RNAs (circRNAs), a novel class of noncoding RNAs, have emerged as crucial contributors to CRC pathogenesis. However, the role of circEIF3I in CRC metastasis remains unclear. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to assess circEIF3I, microRNA (miR)-328-3p, and NCAPH expression. CRC cell migration and invasion were determined via Transwell assays. Western blot analysis was utilized to define the protein expression of epithelial-mesenchymal transition (EMT) markers and NCAPH. Xenograft tumor was established for exploration into the function of circEIF3I in CRC metastasis to the liver and lung. The binding between miR-328-3p and circEIF3I or NCAPH was predicted through ENCORI or TargetScan platform and ascertained through dual-luciferase reporter assays. circEIF3I and NCAPH expression were found to be elevated in CRC tissues and cells, while miR-328-3p was downregulated. Functionally, circEIF3I knockdown inhibited CRC cell migration, invasion, EMT, and tumor metastasis. Mechanistic analyses revealed that circEIF3I can target miR-328-3p, while NCAPH was targeted by miR-328-3p. Furthermore, circEIF3I facilitated NCAPH expression in CRC cells by sequestering miR-328-3p. Notably, miR-328-3p inhibitor or NCAPH overexpression negated the effects of circEIF3I knockdown on preventing CRC progression in vitro. Taken together, circEIF3I elevated NCAPH expression by sponging miR-328-3p, thereby promoting CRC metastasis. These findings suggest that the circEIF3I/miR-328-3p/NCAPH axis represents a novel therapeutic target for CRC.

Zhao Y ，He Y ，Xiao Z ，Xin L ，Deng M ，Yao M ，Huang G ... -  《-》