Parthenolide enhances the metronomic chemotherapy effect of cyclophosphamide in lung cancer by inhibiting the NF-kB signaling pathway

Figure 2 Parthenolide enhanced cytotoxicity of cyclophosphamide on P450 overexpressed Lewis lung cancer cells. A and B: P450 overexpression plasmid (P450-OE) and Control groups were treated with 5 ug/mL (A) or 10 ug/mL (B) cyclophosphamide (CTX), and its inhibitory effect on cell proliferation was evaluated using CCK8 assay; C: Comparison of proliferation inhibition percentage of P450-OE Lewis lung cancer cells (LLCs) treated with 5 and 10 ug/mL CTX; D: Cells were treated with different concentrations of CTX, Parthenolide (PTL), or a combination of the two drugs for 48 hours, and cell viability was detected by CCK-8 assay; E: Inhibition curve of different groups; F: The Combination Index was calculated using CompuSyn software; G: The apoptosis percentage of P450-OE LLC cells was evaluated after 48 hours of exposure to 5 μg/mL CTX and 5 μM PTL individually as well as in combination; H: CCK-8 evaluated the viability of LO2, RLE-6TN and HK-2 cells after treatment with 5 μg/mL CTX and 5 μM PTL individually as well as in combination for 48 hours. n = 3, ^aP < 0.05; ^bP < 0.01; ^cP < 0.001; ^dP < 0.0001. Compared with CTX + PTL group, ^eP < 0.01; ^fP < 0.001; ^gP < 0.0001; NS: Not significant. PTL: Parthenolide; CTX: Cyclophosphamide.