Pyroptosis is involved in the inhibitory effect of FL118 on growth and metastasis in colorectal cancer

Aims: Pyroptosis is a newly discovered inflammatory programmed cell death. This study was to investigate whether pyroptosis is involved in the anti-colorectal cancer process of FL118. Materials and methods: The relationship between NLRP3 and caspase-1 and colorectal cancer was analyzed by bioinformatics. MTT was used to detect the cell viability. Cell membrane integrity was examined by LDH release. Wound healing assay and Transwell were used to detect the cell migration and invasion respectively. TUNEL was to check the cell death. The expression of pyroptosis-related factors was detected using qRT-PCR, Western blotting, Immunofluorescence and Elisa. And H&E staining was used to detect the toxicity of FL118 in colorectal cancer. Key findings: In vitro, FL118 significantly inhibited the proliferation, migration and invasion of colorectal cancer, and the morphological characteristics of pyroptosis were observed under the microscope. With the change of FL118 concentration, the release rate of LDH in the supernatant and the expression of pyroptosisrelated factors emerged an increase. However, pyroptosis induced by FL118 was reversed with the participation of MCC950 and VX-765, which suppressed the antitumor effect of FL118. In vivo, the result in the xenograft animal model and lung metastasis model experimental showed that FL118 could activate pyroptosis and thus inhibit the metastasis of colorectal cancer. Significance: FL118 restrains the growth and metastasis of colorectal cancer by inducing NLRP3-ASC-Caspase-1 mediated pyroptosis, which provides important evidence in the study on the role of pyroptosis and different tumors.