title: Extracellular HSP70-peptide complexes promote the proliferation of hepatocellular carcinoma cells via TLR2/4/JNK1/2MAPK pathway.
abstract: Heat shock protein 70 (HSP70) and HSP70-peptide complexes (HSP70-PCs) have been implicated in the pathogenesis of multiple tumors in humans and have been experimentally shown to increase the proliferation of cell lines derived from hepatocellular carcinoma. The goal of this study was to elucidate the molecular mechanisms through which extracellular HSP70/HSP70-PCs stimulate the proliferation of hepatocellular carcinoma (HCC). The molecular mechanisms of HSP70/HSP70-PC action were studied in the human hepatocellular carcinoma cell lines HepG2 and Huh-7, as well as tumor tissue collected from patients with HCC (n = 95). We found that HSP70/HSP70-PCs can stimulate the proliferation of HepG2 cells and that this effect is blocked by knocking down TLR2 and TLR4 expression by RNA interference. A physical interaction between HSP70/HSP70-PCs and TLR2/4 was established using co-immunoprecipitation and pull-down assays. Pharmacological inhibition of different branches of the MAPK intracellular signaling pathway indicated that the extracellular HSP70/HSP70-PC effect was mediated by the JNK1/2 signaling pathway within the cell. We also studied TLR2 and TLR expression at the protein and messenger RNA (mRNA) level in tumor and non-tumor tissue in patients with HCC (n = 95), finding that TLR2 and 4 are increased in HCC tumor tissue and that the expression of TLR2 correlates with clinicopathologic features of HCC. Our data conclusively demonstrates that extracellular HSP70/HSP70-PCs can promote the proliferation of HCC cells through activation of TLR2 and TLR4 and subsequent activation of the intracellular JNK1/2/MAPK signaling pathway.
authors: School of Stomatology, China Medical University, Shenyang, China.
authors: Yi
authors: Y
authors: Zhe
authors: Department of Oncology, Tumour Angiogenesis and Microenvironment Laboratory (TAML), First Affiliated Hospital, Liaoning Medical College, Jinzhou, China.
authors: Yan
authors: Y
authors: Li
authors: Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, 110004, Liaoning Province, China.
authors: Dan
authors: D
authors: Liu
authors: Center of Metabolic Disease Research, Nanjing Medical University, Nanjing, China.
authors: Dong-Ming
authors: DM
authors: Su
authors: Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, 110004, Liaoning Province, China.
authors: Jin-Gang
authors: JG
authors: Liu
authors: Department of General Surgery, The Fourth Affiliated Hospital of China Medical University, Shenyang, 110004, Liaoning Province, China. sj_li_hangyu@sina.com.
authors: Hang-Yu
authors: HY
authors: Li
mesh_terms: D017209:Apoptosis; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D016022:Case-Control Studies; D049109:Cell Proliferation; D005500:Follow-Up Studies; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D047468:Immunoprecipitation; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D048055:Mitogen-Activated Protein Kinase 8 / Q000235:genetics / Q000378:metabolism; D048056:Mitogen-Activated Protein Kinase 9 / Q000235:genetics / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D009367:Neoplasm Staging; D010446:Peptide Fragments / Q000378:metabolism*; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D051195:Toll-Like Receptor 2 / Q000235:genetics / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D014408:Biomarkers, Tumor; D018840:HSP70 Heat-Shock Proteins; D010446:Peptide Fragments; D012333:RNA, Messenger; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D048056:Mitogen-Activated Protein Kinase 9; D048055:Mitogen-Activated Protein Kinase 8; D020928:Mitogen-Activated Protein Kinases
keywords: Extracellular HSP70-PCs; Hepatocellular carcinoma; JNK1/2MAPK; Proliferation; TLR2; TLR4