Preliminary Study Of The Hippo Pathway Kinases Lats1/2 On Tumormicroenvironment

Recent studies have shown that Hippo signaling in tumor cells plays an important role in both immune stimulation and immunosuppression.These involve cytokines production,immune checkpoint molecule expression,extracellular vesicle release from the tumor cells,and allowing for intercellular communication and orchestrating the immune responses.Here we report that loss of the Hippo pathway kinases Lats1/2(large tumor suppressor 1 and 2)in mice will lead to oncogenesis,the Lats1/2 deficient sarcoma inhibits the growth of mouse subcutaneous MC38(mouse colon cancer cell line)tumors.Through preliminary analysis of the whole tumor microenvironment,we found that the tumor microenvironment mixed with Lats1/2-DKO(Lats1/2 double gene knockout)tumor cells upregulate the transcription level of CXCL9、CXCL10,chemokines that induce T-cell transport,and the transcription level of IFNγ,TNFα,Perforin,killer cytokines.Further flow analysis showed that the number of tumor infiltrated immune cells is also significantly upregulated.These experimental results indicated that Lats1/2-DKO tumor cells may have the potential to heat up cooler tumors.In order to further verify whether the change of tumor microenvironment is specifically dependent on Lats1/2,we deleted Lats1/2 in B16 F10 melanoma cells using CRISPR/Cas9 genome-editing technology.Genome sequencing and protein detection showed that Lats1/2 was successfully knocked out.In addition,B16 F10-Lats1/2 DKO cell line shows stronger YAP nuclear localization,and activated Yap regulates the expression of growth-related factor CTGF,CYR61,leading to stronger clonal formation ability.This provides a reliable experimental model for further studying the role of Lats 1/2 in changing tumor microenvironment.