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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Aged, Aged, 80 and over, Animals, Axons, Carcinoma, Cell Line, Tumor, Cell Migration Inhibition, Cell Proliferation, Chemotactic Factors, Colorectal Neoplasms, Female, Gene Expression Regulation, Neoplastic, Genetic Therapy, Humans, Male, Membrane Proteins, Mice, Mice, Nude, Middle Aged, Neoplasm Metastasis, Nerve Tissue Proteins, RNA, Small Interfering, Xenograft Model Antitumor Assays.
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Does endogenous axon guiding chemorepulsant semaphorin-3F inhibit the growth and metastasis of colorectal carcinoma? Context: To elucidate the role of Semaphorin-3F (SEMA3F), originally described as an axon guiding chemorepulsant implicated in nerve development, in the progression of colorectal carcinoma. SEMA3F and its receptor NRP2 were examined in 72 cases of human colorectal carcinoma specimens and cell lines LoVo, SW480, and SW620 with immunohistochemistry and Western blotting. SEMA3F mRNA expression in the frozen tissue specimens and cell lines was examined with quantitative reverse transcriptase-PCR. Confocal laser scanning microscopy was used for detection of cellular localization of the proteins by immunofluorescent staining. MTT assay, flow cytometry, cell adhesion and migration, and xenografts were used to evaluate biological significance of SEMA3F. SEMA3F was significantly reduced in colorectal carcinoma tissues and cell lines. Overexpression of SEMA3F resulted in reduced proliferation, adhesion to fibronectin, and migratory capability as well as reduced S-phase population and integrin αvβ3 expression of SW480 colon cancer cells. In addition, SEMA3F-overexpressing cells exhibited diminished tumorigenesis when transplanted orthotopically in nude mice and reduced liver metastases. Moreover, transfection of siRNA targeting SEMA3F in colon cancer cells increased their tumorigenicity in vivo.
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Endogenous SEMA3F acts as a suppressor of the growth and metastasis of human colorectal cancer cells. Final Decision: yes