Figure 6. Hsa_circ_0000199-miR-613/miR-206 axis was implicated in modifying chemosensitivity of triple-negative breast cancer (TNBC) cells. (A–D) Resistance of MDA-MB-231 and MDA-MB-468 cell lines against cisplatin (A), adriamycin (B), paclitaxel (C) and gemcitabine (D) was compared among si-hsa_circ_0000199+miR-613 inhibitor, si-hsa_circ_0000199 and NC groups. *: compared with NC group; #: compared with si-hsa_circ_0000199 group; **/##: P<0.01; ***/###: P<0.001. (E–H) Sensitivity of MDA-MB-231 and MDA-MB-468 cell lines responding to cisplatin (E), adriamycin (F), paclitaxel (G) and gemcitabine (H) was assessed after treatments of si-hsa_circ_0000199+miR-206 inhibitor, si-hsa_circ_0000199 and none. *: compared with NC group; #: compared with si-hsa_circ_0000199 group; */#: P<0.05; **/##: P<0.01; ***/###: P<0.001.