Figure 5.

Erlotinib effect on surface-associated death receptors and other immune-relevant molecules. (a) FAS expression levels were measured via FACS analysis in HCC827 and PC9 cells. (b) TRAIL receptor-1 and -2 mRNA levels were measured via qRT-PCR in cells treated as indicated. (c) NKG2D receptor levels were assessed via FACS analysis on NK cells isolated from two normal donors. (d) PC9 or HCC4006 cells were left untreated (0 h) or were pre-treated with 100 nM erlotinib for 16 or 72 h. Tumor cells were collected, washed and subsequently exposed to a mixture of the chemotherapeutics cisplatin and vinorelbine for 96 h, or left untreated. Cell survival was evaluated by Cell Titer-Glo; represented is the percentage of tumor cell lysis induced by chemotherapy treatment, calculated for each group (erlotinib 0, 16, or 72 h) as: [fluorescent counts chemotherapy treated wells/fluorescent counts untreated wells] × 100