ACTA1 and neoplasm: These results strongly suggested that α-SMA-positive CAFs provide some growth-promoting signals to neighbouring cancer cells, which led to tumour regrowth, and the difference in the potencies of the treatments for reducing such tumour-promoting α-SMA-positive CAFs can account for their different antitumour activities in terms of the suppression of regrowth between treatment with E7130 and CTX and treatment with paclitaxel and CTX.