Interactions Between Specific Driver Genes Shape The Signaling Pathway Landscape And Direct The Treatment Of Hepatocellular Carcinoma

Cancer initiation and development are driven by alterations in driver genes.Hepatocellular carcinoma(HCC)is one of the most lethal and fastest growing malignancies worldwide.Several multi-kinase inhibitors are now approved for the treatment of advanced patients with HCC.However,unfortunately,patient response rates were low,and it remains poorly understood why only a fraction of individuals with HCC respond to the standard treatment.Thus,our aim was to investigate the differences between patients with HCC based on tumor molecular classification,and provide targeted therapeutic options for them.Our study elicited three important findings:First,we identified four dual driver gene combinations(TP53+PTEN,PTEN+CTNNB1,PTEN+KRAS,and TP53+KRAS),that exhibited a high frequency of somatic mutation or copy number variations(CNVs),using the TCGA database.The proportion of HCC patients with copy number changes of TP53+PTEN combination was 32%.The ratio of PTEN+CTNNB1 combination change was 16%;The ratio of PTEN+KRAS combination change was 15%.The proportion of TP53+KRAS combination change was 24%.Second,we constructed four spontaneous mouse models of HCC with the driver gene alterations indicated above.We identified the phenotypic characteristics of four murine tumors using pathological diagnosis,histochemical staining and mouse Bmodel ultrasound.In general,Ptenmut+Ctnnb1mut tumor model has the lowest degree of malignancy and slow tumor progression,while Trp53mut+KrasG12D tumor model has the highest degree of malignancy,rapid tumor progression and short survival time.Third,we used RNA-seq and protein phosphorylation microarray analysis of murine tumor tissues to reveal the kinase signaling pathway landscape of HCC induced by different driver gene combinations.We also verified our findings using human samples.We found that the Trp53mut+Ptenmut tumor upregulated mTOR and noncanonical NF-κB signaling,the Ctnnb1mut+Ptenmut tumor upregulated JAK-STAT signaling,the Ptenmut+KrasG12D tumor upregulated MTOR,cytoskeleton,and AMPK signaling,while the Trp53mut+KrasG12D tumor upregulated JAK-STAT,MAPK,and cytoskeleton pathways.Importantly,we screened out inhibitors targeting the implicated kinase signaling cascades,that displayed potent anti-proliferative effects in vitro in our mouse models.Last,we tested the potency of the selected kinase signaling pathway inhibitors in subcutaneous tumors constructed from mouse primary cell lines,where they exhibited excellent therapeutic potential.The Trp53mut+Ptenmut tumor was strongly inhibited by rapamycin(an mTOR inhibitor)in vilro and in vivo.In the Trp53mut+KrasG12D tumor,napabucasin(a STAT3 inhibitor)displayed potent anti-proliferative effects.The combination of sorafenib and rapamycin elicited the complete inhibition of tumor growth in the Ptenmut+KrasG12D tumors.In summary,the high heterogeneity of liver cancer inspired us to customize precise treatment plans for liver cancers with different molecular classifications.We thus constructed tumor models induced by different driver genes,and explored the unique signaling pathways downstream of each model.Based on this,our study provides targeted therapeutic options for the clinical treatment of HCC.