RESUMO
Major gaps in understanding the molecular mechanisms of colorectal cancer (CRC) progression and intestinal mucosal repair have hampered therapeutic development for gastrointestinal disorders. Trefoil factor 3 (TFF3) has been reported to be involved in CRC progression and intestinal mucosal repair; however, how TFF3 drives tumors to become more aggressive or metastatic and how TFF3 promotes intestinal mucosal repair are still poorly understood. Here, we found that the upregulated TFF3 in CRC predicted a worse overall survival rate. TFF3 deficiency impaired mucosal restitution and adenocarcinogenesis. CD147, a membrane protein, was identified as a binding partner for TFF3. Via binding to CD147, TFF3 enhanced CD147-CD44s interaction, resulting in signal transducer and activator of transcription 3 (STAT3) activation and prostaglandin G/H synthase 2 (PTGS2) expression, which were indispensable for TFF3-induced migration, proliferation, and invasion. PTGS2-derived PGE2 bound to prostaglandin E2 receptor EP4 subtype (PTGER4) and contributed to TFF3-stimulated CRC progression. Solution NMR studies of the TFF3-CD147 interaction revealed the key residues critical for TFF3 binding and the induction of PTGS2 expression. The ability of TFF3 to enhance mucosal restitution was weakened by a PTGS2 inhibitor. Blockade of TFF3-CD147 signaling using competitive inhibitory antibodies or a PTGS2 inhibitor reduced CRC lung metastasis in mice. Our findings bring strong evidence that CD147 is a novel receptor for TFF3 and PTGS2 signaling is critical for TFF3-induced mucosal restitution and CRC progression, which widens and deepens the understanding of the molecular function of trefoil factors.
Assuntos
Basigina/genética , Neoplasias Colorretais/tratamento farmacológico , Ciclo-Oxigenase 2/genética , Receptores de Prostaglandina E Subtipo EP4/genética , Fator Trefoil-3/genética , Animais , Basigina/antagonistas & inibidores , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Ligação Proteica/efeitos dos fármacos , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Mounting evidence suggests that solid tumors display the features of collective invasion, however, the molecular mechanisms are far from clear. This study aims to verify the role and the underlying mechanisms of CD147 in collective invasion in hepatocellular carcinoma. METHODS: Immunostaining was used to analyze human hepatocellular carcinoma specimens and three-dimensional cultures. Three-dimensional invasion model was established to mimic in vivo invasion. RNA-sequencing was used to identify downstream effectors. RESULTS: Human hepatocellular carcinoma underwent collective invasion and CD147 was observed to be upregulated at the invasive front of tumor cell groups. CD147 was demonstrated to promote collective invasion using the modified three-dimensional invasion model, which recapitulated the main features of collective invasion. Through transcriptome analysis and enzyme activity assay, we found that CD147 enhanced cathepsin B expression and activity. Upregulated cathepsin B in hepatocellular carcinoma cells facilitated migration and invasion, which mediated CD147-induced invasive phenotype in hepatocellular carcinoma. In terms of mechanism, we found that CD147 promoted cathepsin B transcription by activating ß-catenin signaling as a result of reduced GSK-3ß expression. Furthermore, we found that elevated expression of CD147 as well as cathepsin B were correlated with poor prognosis in patients with hepatocellular carcinoma. CONCLUSIONS: CD147 promotes hepatocellular carcinoma cells collective invasion via upregulating cathepsin B expression and targeting CD147 would be valuable for the development of novel therapeutic modalities against invasion and metastasis of cancer.
Assuntos
Basigina/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/secundário , Catepsina B/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Animais , Apoptose , Basigina/genética , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Catepsina B/genética , Proliferação de Células , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: CD147 is a tumor-associated antigen that plays a key regulatory role in tumor invasion and distant metastasis. However, the exact role of CD147 phosphorylation, which is deregulated during cancer progression, is unknown. Here, the effects of CD147 phosphorylation on the malignant behavior of hepatocellular carcinoma (HCC) cells and its possible underlying mechanisms are explored. METHODS: An in situ Duolink-proximity ligation assay (PLA) was used to detect CD147 phosphorylation. Tandem mass spectrometry was employed to identify the phosphorylation sites of CD147. The effects of CD147 phosphorylation on the malignant behavior of HCC cells were evaluated using scratch wound healing assays, transwell invasion assays and cell cycle assays. The genes regulated by CD147 phosphorylation were detected by RNA sequencing. RESULTS: We identified phosphorylated serine-246 in the C terminus of CD147 in primary HCC tissues, whereas serine to alanine substitution mutation analysis suggested that CD147 is phosphorylated mainly at serine-252 in HCC-derived Huh-7 cells. Recovery expression of S246A/S252A mutants in CD147 knockout cells revealed significantly increased migration and invasion capacities compared to wildtype CD147 expressing cells. Cyclophilin A (CyPA) treatment decreased the phosphorylation level of CD147, whereas NIMA-related kinase 6 (NEK6) increased the CD147 phosphorylation level. Moreover, the CD147 phosphorylation level was found to be dramatically decreased in HCC tissues in patients with distant metastases, and a low phosphorylation level of CD147 was found to be associated with a high serum AFP level, recurrence and a poor overall survival. CONCLUSIONS: From our data we conclude that hypo-phosphorylated CD147 promotes the migration and invasion of HCC cells and correlates with an unfavorable prognosis in HCC patients, indicating that targeting the aberrantly hypo-phosphorylated form of CD147 may be instrumental for the development of novel therapeutic modalities directed against HCC metastasis.