title: The selective cyclooxygenase-1 inhibitor SC-560 suppresses cell proliferation and induces apoptosis in human hepatocellular carcinoma cells.
abstract: Two isoforms of cyclooxygenase (COX) are known, and to date most studies have implicated COX-2 in the development and progression of various human cancers. Increasing evidence suggests that COX-1 may also play a similar role. Indeed, we have recently observed that the dual COX-1/COX-2 inhibitor indomethacin induces apoptosis in human hepatocellular carcinoma (HCC) cell lines more effectively than the selective COX-2 inhibitors, possibly implicating COX-1 in HCC. In this study we investigated the expression of COX-1 in non-tumor and malignant human liver tissues, as well as the effects of the highly selective COX-1 inhibitor SC-560 on cell growth and apoptosis in human HCC cell lines. Expression of COX-1 was detected in nearly all the samples assayed, although with a high variability between non-tumoral (NT) and malignant tissues. The percentage of COX-1 positive cells was significantly higher in the NT tissues than in the tumors (p<0.0001). In well-differentiated HCC COX-1 expression was significantly higher than in the poorly-differentiated tissues (p<0.05). SC-560 showed a dose- and time-dependent inhibitory effect on HCC cell growth. The combination of the COX-1 inhibitor with nimesulide and CAY10404, two selective COX-2 inhibitors, resulted in additive effects on cell growth inhibition. SC-560 also inhibited colony formation in soft agar and induced apoptosis in HCC cells in a dose-dependent manner. Moreover, SC-560 decreased the levels of the anti-apoptotic proteins survivin and XIAP and activated caspase-3 and -7 in a dose- and time-dependent fashion. In conclusion, we report for the first time that the selective COX-1 inhibitor SC-560 exhibits anti-tumor and apoptotic effects in human HCC cells. Overall, our previous and present results suggest that both COX-1 and COX-2 inhibitors may have potential therapeutic implications in HCC patients.
authors.affiliation: Istituto di Biomedicina e Immunologia Molecolare 'Alberto Monroy, C.N.R., Palermo, Italy.
authors.forename: Nadia
authors.initials: N
authors.lastname: Lampiasi
authors.forename: Daniela
authors.initials: D
authors.lastname: Foderà
authors.forename: Natale
authors.initials: N
authors.lastname: D'Alessandro
authors.forename: Antonella
authors.initials: A
authors.lastname: Cusimano
authors.forename: Antonina
authors.initials: A
authors.lastname: Azzolina
authors.forename: Claudio
authors.initials: C
authors.lastname: Tripodo
authors.forename: Ada Maria
authors.initials: AM
authors.lastname: Florena
authors.forename: Marta Ida
authors.initials: MI
authors.lastname: Minervini
authors.forename: Monica
authors.initials: M
authors.lastname: Notarbartolo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Montalto
authors.forename: Melchiorre
authors.initials: M
authors.lastname: Cervello
mesh_terms: D000368:Aged; D017209:Apoptosis / Q000187:drug effects*; D006528:Carcinoma, Hepatocellular / Q000201:enzymology* / Q000235:genetics / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D051545:Cyclooxygenase 1 / Q000235:genetics / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011720:Pyrazoles / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D016861:Cyclooxygenase Inhibitors; D011720:Pyrazoles; D012333:RNA, Messenger; C115461:SC 560; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2