Research Article

Exosomal lncRNA PVT1/VEGFA Axis Promotes Colon Cancer Metastasis and Stemness by Downregulation of Tumor Suppressor miR-152-3p

Figure 2

Comparative analysis of exosomes from the serum of patients with primary and metastatic colon cancer. (a) Serum exosomes were isolated from patients with primary tumor (P-exo) and distant metastasis (M-exo). Representative electromagnetic images of exosomes are shown. Scale bar: 200 nm. Western blots demonstrated increased CD9 and MCT1 (exosome markers) and cyclin D1 (tumor-specific marker) in the serum of patients with metastatic colon cancer (M, M-exo) compared with that of patients with primary tumor (P, P-exo). Serum exosomes of normal healthy people were included as controls (N, normal). (b) Comparative qPCR analysis showed that the levels of PVT1 and VEGFA were significantly higher in the M-exo than in the P-exo. (c) The sphere-forming assay showed that the addition of M-exo led to formation of an increased number of tumorspheres in both cell lines compared with controls and the group with P-exo. (d) Exosomes and colon cancer cell line coculture experiment. HCT116 and LoVo cells cocultured with M-exo demonstrated enhanced migratory and invasive abilities. (e) Western blot analysis indicated an elevation in metastatic markers, namely, Twist1, vimentin, and MMP2, and the stemness marker Sox2 in HCT116 and LoVo cells cocultured with M-exo compared with their counterparts cultured with P-exo. Coculture with exosomes derived from the serum of healthy individuals served as control. ; ; . Scale bar: 100 μm.
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