The host Toll-like Receptor-2 (TLR2) and Toll-like Receptor-4 (TLR4) play critical roles in defense against Escherichia coli (E. coli) infection is well-known. The NLR pyrin domain-containing 3 (NLRP3) inflammasome is also an important candidate during the host-recognized pathogen, while the roles of NLRP3 in the host inflammatory response to E. coli infection remains unclear. This study aimed to explore the roles of NLRP3 in regulating the inflammatory response in E. coli infection-induced mice. Our result indicated that compared to wild-type mice, the TLR2-deficient (TLR2-/-), TLR4-deficient (TLR4-/-), and NLRP3-deficient (NLRP3-/-) mice had significant decrease in liver damage after stimulation with Lipopolysaccharide (LPS, 1 μg/mL), Braun lipoprotein (BLP, 1 μg/mL), or infected by WT E. coli (1 × 107 CFU, MOI 5:1). Meanwhile, compared with wild-type mice, the TNF-α and IL-1β production in serum decreased in TLR2-/-, TLR4-/-, and NLRP3-/- mice after LPS, BLP treatment, or WT E. coli infection. In macrophages from NLRP3-/- mice showed significantly reduced secretion of TNF-α and IL-1β in response to stimulation with LPS, BLP, or WT E. coli infection compared with macrophages from wild-type mice. These results indicate that besides TLR2 and TLR4, NLRP3 also plays a critical role in host inflammatory responses to defense against E. coli infection, and might provide a therapeutic target in combating disease with bacterium infection.
Lymphocyte antigen 6 complex, locus K (LY6K) is a putative oncogene in various human cancers, including colorectal cancer, where elevated expression is associated with poor prognosis. This study investigates the antitumor effects of LY6K in colon cancer stem cells (CCSCs) both in vitro and in vivo. EpCAM and CD44 surface markers were used to isolate CCSCs from HCT116 cells, and the expression of LY6K in CCSCs was analyzed by real-time PCR. RNA interference was used to silence LY6K to evaluate its potential role of LY6K on the proliferation, migration, invasion, and cell cycle of CCSCs. Functional assays, including MTS assays, flow cytometric analyses, Transwell migration and invasion assays, and a xenograft model, were used for analysis. The results revealed that LY6K was highly expressed in CCSCs. siRNA-mediated LY6K-silencing in CCSCs inhibited cell proliferation by inducing G1 phase cell cycle arrest and suppressed migration and invasion. In vivo, LY6K silencing effectively reduced tumor growth and extended survival in a mouse model. These findings suggest LY6K as a promising therapeutic target for eradicating CCSCs in colorectal cancer treatment.