RESUMO
BACKGROUND AND AIM: Trophoblast cell surface antigen 2 (TROP2) or tumor-associated calcium signal transducer 2 (TACSTD2) is a 36-kDa type I transmembrane glycoprotein and exerts dual functions as an oncogene and tumor suppressor in cancer cells. In this study, we investigated the expression and functions of TROP2 in liver fluke-associated cholangiocarcinoma (CCA). MATERIAL AND METHODS: TROP2 expression in 85 CCA tissues was detected by using immunohistochemistry. The methylation status of TROP2 promoter was studied in 15 matched pairs of normal and CCA formalin fixed paraffin embedded (FFPE) tissues using the bisulfite genomic sequencing (BGS) method. The functions of TROP2 on cancer cell behavior were investigated using siRNA in CCA cell lines. Proliferation, migration and invasion assays were performed. A PCR array was used to evaluate the impact of TROP2 knockdown on the gene expression profiles. RESULTS: TROP2 was highly expressed in all normal bile duct epithelia, but significantly down-regulated in CCA cells. Sixty percent of CCA revealed promoter hypermethylation compared to the corresponding adjacent normal tissues. TROP2 knockdown significantly enhanced the proliferation and migration in CCA cell lines, and altered the expressions of MARCK, EMP1 and FILIP1L. CONCLUSION: We provide new evidence that TROP2 is epigenetically down-regulated and operates as a negative regulator of cell proliferation and migration in liver fluke-associated CCA.
Assuntos
Antígenos de Neoplasias/metabolismo , Neoplasias dos Ductos Biliares/metabolismo , Moléculas de Adesão Celular/metabolismo , Movimento Celular , Proliferação de Células , Colangiocarcinoma/metabolismo , Fasciola hepatica/isolamento & purificação , Fasciolíase/parasitologia , Animais , Neoplasias dos Ductos Biliares/parasitologia , Neoplasias dos Ductos Biliares/patologia , Linhagem Celular Tumoral , Colangiocarcinoma/parasitologia , Colangiocarcinoma/patologia , Metilação de DNA , Epigênese Genética , Fasciolíase/complicações , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Substrato Quinase C Rico em Alanina Miristoilada , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas , Interferência de RNA , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Fatores de Tempo , TransfecçãoRESUMO
Methionine aminopeptidase-2 (MetAP2) is over-expressed in several cancers, including the cholangiocarcinoma (CCA). We reported previously suppressive effects of fumagillin, a MetAP2 inhibitor, on growth of CCA cell lines. In the present study, we evaluated the anti-proliferative and anti-invasive activities of TNP-470, a fumagillin analogue with higher MetAP2 inhibitory activity, on CCA cell lines (KKU-M213 and KKU-M214). TNP-470 significantly inhibited growth of both lines in a dose and time dependent fashion. Moreover, a sub-toxic dose of TNP-470 significantly reduced migration and invasion of CCA cells. Exploration of the molecular mechanisms by which TNP-470 inhibited growth and metastasis of CCA cell lines demonstrated expression of c-MYC, MMP2 and MMP9 to be decreased in TNP-470 treated cells. These results suggest that TNP-470 could be a potential therapeutic agent for CCA.
Assuntos
Proliferação de Células , Colangiocarcinoma , Aminopeptidases , Neoplasias dos Ductos Biliares , Ductos Biliares Intra-Hepáticos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , MetioninaRESUMO
Poor prognosis of cholangiocarcinoma (CCA) is primarily due to delayed diagnosis because of the lack of appropriate tumor marker(s) to detect cancer development at an early stage. We have recently established a S121 monoclonal antibody (mAb) which recognizes an unidentified glycan epitope on MUC5AC, designated as CCA-associated carbohydrate antigen (CCA-CA). This antigen is expressed in human CCA cells but not in normal biliary epithelia. Detection of CCA-CA effectively distinguished CCA patients' sera from normal control sera with high specificity and sensitivity. In the present study, we examined a time profile of the expression of CCA-CA by immunohistochemical methods in the liver tissues of Opisthorchis viverrini (Ov)-associated CCA in a hamster model. Hamsters were divided into four groups; non-treated, Ov infected, NDMA (N-nitrosodimethamine) treated and Ov+NDMA treated groups, and animals from each group were euthanized at 1, 3 and 6 months post-treatment. CCA-CA was not detected in normal biliary cells of non-treated hamsters throughout the course of experiment. CCA-CA became detectable in the cytoplasm and apical surface of biliary cells of the NDMA and Ov+NDMA groups at early stage (1 month) of tumor development and increased with tumor progression. In contrast, CCA-CA was detected as nuclear staining at the 1 month post Ov infection and declined thereafter. These results suggest the possibility of CCA-CA as an early marker for CCA.
