FIGURE 6.

Heparanase regulates temozolomide (TMZ) resistance in glioma cells by enhancing hsa_circ_0042003 expression. Exosomes were isolated from U251R cells transfected with si‐heparanase, or U251 cells transfected with pcDNA‐heparanase. A, B, Expression of exosomal hsa_circ_0042003 was analyzed using quantitative real‐time PCR (qRT‐PCR). C, After U251R cell transfection with si‐heparanase, hsa_circ_0042003 expression in U251R cells was detected using qRT‐PCR. D, After U251 cell transfection with pcDNA‐heparanase, hsa_circ_0042003 expression in U251 cells was detected using qRT‐PCR. E, U251 cells were cocultured with exosomes (exo) derived from U251 or U251R cells, and then hsa_circ_0042003 expression in U251 cells was detected using qRT‐PCR. U251 cells were cocultured with exosomes derived from U251R cells transfected with si‐hsa_circ_0042003, or U251 cells transfected with pcDNA‐hsa_circ_0042003. F, G, CCK‐8 assay was used to evaluate the viability of U251 cells. H, J, Proliferation of U251 cells was evaluated using EdU assay. Scale bar = 50 μM. I, K, Apoptosis of U251 cells was analyzed using flow cytometry. **P < .01; ***P < .001