IL15 and colorectal carcinoma: Moreover, Ki67 staining and TUNEL assay were applied to determine the regulatory role of IL-15 on cell proliferation and apoptosis, and the results showed that lower proliferation rate and higher TUNEL-positive rate (representing a higher apoptosis rate) were shown in DMA-pIL15-treated group in comparison with the control group, which demonstrated that IL-15 exhibited antitumour effect via inhibiting the proliferation and promoting apoptosis of CRC cells.