Direct interaction of platelet with tumor cell aggravates hepatocellular carcinoma metastasis by activating TLR4/ADAM10/CX3CL1 axis.

Metastasis is the main culprit of cancer-related death and account for the poor prognosis of hepatocellular carcinoma. Although platelets have been shown to accelerate tumor cell metastasis, the exact mechanism remained to be fully understood. Here, we found that high blood platelet counts and increased tumor tissue ADAM10 expression indicated the poor prognosis of HCC patients. Meanwhile, blood platelet count has positive correlation with tumor tissue ADAM10 expression. In vitro, we revealed that platelet increased ADAM10 expression in tumor cell through TLR4/NF-κB signaling pathway. ADAM10 catalyzed the shedding of CX3CL1 which bound to CX3CR1 receptor, followed by inducing epithelial to mesenchymal transition and activating RhoA signaling in cancer cells. Moreover, knockdown HCC cell TLR4 (Tlr4) or inhibition of ADAM10 prevented platelet-increased tumor cell migration, invasion and endothelial permeability. In vivo, we further verified in mice lung metastatic model that platelet accelerated tumor metastasis via cancer cell TLR4/ADAM10/CX3CL1 axis. Overall, our study provides new insights into the underlying mechanism of platelet-induced HCC metastasis. Therefore, targeting the TLR4/ADAM10/CX3CL1 axis in cancer cells hold promise for the inhibition of platelet-promoted lung metastasis of HCC.

Platelets promote primary hepatocellular carcinoma metastasis through TGF-ß1-mediated cancer cell autophagy.

Previous research has revealed that platelets promote tumor metastasis by binding to circulating tumor cells (CTCs). However, the role of platelets in epithelial-mesenchymal transition (EMT) of cancer cells at the primary tumor site, the crucial initial step of tumor metastasis, remains to be elucidated. Here, we found that platelet releasate enhanced EMT and motility of hepatocellular carcinoma (HCC) cells via AMPK/mTOR-induced autophagy. RNA-seq indicated that platelet releasate altered TGF-ß signaling pathway of cancer cells. Inhibiting TGFBR or deleting platelet TGF-ß1 suppressed AMPK/mTOR pathway activation and autophagy induced by platelet releasate. Compared with Pf4cre-; Tgfb1fl/fl mice, HCC orthotopic models established on Pf4cre+; Tgfb1fl/fl mice showed reduced TGF-ß1 in primary tumors, which corresponded with decreased cancer cell EMT, autophagy, migration ability and tumor metastasis. Inhibition of autophagy via Atg5 knockdown in cancer cells negated EMT and metastasis induced by platelet-released TGF-ß1. Clinically, higher platelet count correlated with increased TGF-ß1, LC3 and N-cad expression in primary tumors of HCC patients, suggesting a link between platelets and HCC progression. Our study indicates that platelets promote cancer cell EMT in the primary tumor and HCC metastasis through TGF-ß1-induced HCC cell autophagy via the AMPK/mTOR pathway. These findings offer novel insights into the role of platelets in HCC metastasis and the potential therapeutic targets for HCC metastasis.

Genomic evolution shapes prostate cancer disease type.

The development of cancer is an evolutionary process involving the sequential acquisition of genetic alterations that disrupt normal biological processes, enabling tumor cells to rapidly proliferate and eventually invade and metastasize to other tissues. We investigated the genomic evolution of prostate cancer through the application of three separate classification methods, each designed to investigate a different aspect of tumor evolution. Integrating the results revealed the existence of two distinct types of prostate cancer that arise from divergent evolutionary trajectories, designated as the Canonical and Alternative evolutionary disease types. We therefore propose the evotype model for prostate cancer evolution wherein Alternative-evotype tumors diverge from those of the Canonical-evotype through the stochastic accumulation of genetic alterations associated with disruptions to androgen receptor DNA binding. Our model unifies many previous molecular observations, providing a powerful new framework to investigate prostate cancer disease progression.