Based on our preliminary findings we hypothesized that treatment of MMs with chemotherapeutic drugs may elevate the levels of NLRP3 and caspase-1 resulting in increased cell death by pyroptosis while increasing the levels of IL-1β and other pro-inflammatory molecules.
Using in vitro models with mouse and human malignant mesothelioma cells, curcumin is shown to induce pyroptosis through activation of caspase-1 and increased release of high-mobility group box 1 (HMGB1) without processing of IL-1β and IL-18.
These data indicate that (a) normal human mesothelial cells spontaneously express detectable levels of M-CSF mRNA in culture; (b) EGF is an essential cofactor for optimal induction of G-CSF and GM-CSF expression; (c) exposure of normal mesothelial cells to inflammatory mediators such as LPS and TNF increases the levels of transcripts for CSFs and IL-1 beta; and (d) as compared with normal human mesothelial cells, some cell lines of human malignant mesothelioma exhibit aberrant gene expression for multiple cytokines, including G-CSF, GM-CSF, IL-1 beta, and IL-6.