SPC212 (a) and SPC111 (b) cells were cultured and treated with 5 μM QU, 10 μM QU, 50 μM QU, and 100 μM QU for 0–96 hours. Applications of QU > 10 μM and QU ≥ 50 μM caused reduction of cell numbers in SPC212 and SPC111 cells at 72 hours, respectively. Data was statistically evaluated between control group and multiple dose groups of QU, with the level of significance chosen as *P < .05 and **P < .01.

SPC212 (a) and SPC111 (b) cells were untreated and treated with 5 μg/ml CIS, 10 μg/mL CIS, 50 μM QU and 5 μg/mL CIS + 50 μM QU, and 10 μg/mL CIS + 50 μM QU for 0–96 hours. Cell proliferation decrease imposed by QU, CIS, and QU + CIS was time dependent. Combination treatments were found more effective than individual treatments in SPC212 cells in 96 hours (a). Additionally, both individual and combination applications reduced cell proliferation in SPC111 cells when compared with untreated cells in 96 hours (b); however no significant differences were observed on the reduction of cell proliferation when compared with combined and individual treatments in 96 hours. Data was statistically evaluated between control group, single dose groups, and combination dose groups, with the level of significance chosen as *P ≤ .05; **P ≤ .01, and ^#P < .05 between QU + CIS treatment and CIS alone.

SPC212 cells ((a) and (b)) and SPC111 cells ((c) and (d)) were untreated, treated with 5 μg/mL CIS, 10 μg/mL CIS, 50 μM QU, and combination of both at 24 hours ((a) and (c)) and 48 hours ((b) and (d)). Accumulation of cells in S phase was detected in SPC212 but not in SPC111 cells following QU treatments for 48 hours ((b) and (d)). However, individual CIS applications resulted in accumulation of both cells in S phase at the first 24 hours period ((a) and (c)), and cells were arrested at G₂/M phase in the following 24 hours ((b) and (d)). Distribution of cell cycle was altered in both cells with 5 μg/mL CIS + 50 μM QU treatment compared with untreated cells and cells were treated with individual agents. The percentage of S phase arrest was observed as 86.7% in SPC212 and 99% in SPC111 cells, at 48 hours ((b) and (d)). On the other hand, cells treated with 10 μg/mL CIS + 50 μM QU showed a similar profile to that of individual 10 μg/mL CIS dose applications in SPC111 cells ((c) and (d)).

SPC212 ((a) and (b)) and SPC111 cells ((c) and (d)) were treated with 5 μg/mL CIS, 10 μg/mL CIS, 50 μM QU, 5 μg/mL CIS + 50 μM QU, and 10 μg/mL  CIS + 50 μM QU for 48 hours. C9 ((a) and (c)) and C3 ((b) and (d)) activities were measured as indicated in Section 2.5 compared to control and single agent treatments. 10 μg/mL CIS + 50 μM QU combinations activated C9 in both cell lines for 48 hours ((a) and (c)). C9 and C3 activities were increased in SPC212 cells following 10 μg/mL CIS + 50 μM QU at 24 hours when compared to the control cells and the cells treated with individual doses of QU and CIS ((a) and (b)). Additionally, 5 μg/mL CIS + 50 μM QU combination treatments of SPC212 cells were found effective to activate C9 and C3 molecules at 48 hours ((a) and (b)). In addition C9 was activated with 10 μg/mL CIS + 50 μM QU applications on SPC111 cells. However, there was no C3 activity detected in SPC111 cells for 48 hours (d). Data was statistically evaluated between control group, single dose groups and combination dose groups, with the level of significance chosen as *P ≤ .05, **P ≤ .01, ^#P < .05 between QU + CIS treatment and CIS alone, and ^##P < .05 between QU + CIS treatment and QU alone.