Details

Autor(en) / Beteiligte

• YEE SOOK CHO
• KIM, Meyoung-Kon
• TAN, Langzhu
• SRIVASTAVA, Rakesh
• AGRAWAL, Sudhir
• CHO-CHUNG, Yoon S

Titel

Protein Kinase A RIα Antisense Inhibition of PC3M Prostate Cancer Cell Growth: Bcl-2 Hyperphosphorylation, Bax Up-Regulation, and Bad-Hypophosphorylation

Ist Teil von

• Clinical cancer research, 2002-02, Vol.8 (2), p.607-614

Ort / Verlag

Philadelphia, PA: American Association for Cancer Research

Erscheinungsjahr

2002

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• It has been shown that expression of the RIα subunit of cyclic AMP (cAMP)-dependent protein kinase is enhanced in human cancer cell lines, primary tumors, and cells after transformation. Using an antisense strategy, we have shown that RIα has a role in neoplastic cell growth in vitro and in vivo . In the present study, we have investigated the sequence- and target-specific effects of exogenous RIα antisense oligodeoxynucleotides (ODNs) and endogenous antisense gene on tumor growth, apoptosis, and cAMP signaling in androgen-insensitive prostate cancer cells, both in vitro and in nude mice. Here, we show that an RIα antisense, RNA/DNA mixed backbone ODN exerts a reduction in RIα expression at both the mRNA and protein levels, up-regulation of both the RIIβ subunit of cAMP-dependent protein kinase or protein kinase A and c-AMP-phosphodiesterase IV expression, and inhibition of cell growth. Growth inhibition was accompanied by changes in cell morphology and the appearance of apoptotic nuclei. In addition, Bcl -2 hyperphosphorylation; increase in the proapoptotic proteins Bax, Bak, and Bad; and Bad hypophosphorylation occurred in the antisense-treated cells. These effects of exogenously supplied antisense ODN mirrored those induced by endogenous antisense gene overexpression. The RIα antisense ODNs, which differed in sequence or chemical modification, promoted a sequence- and target-specific reduction in RIα protein levels and inhibited tumor growth in nude mice. These results demonstrate that in a sequence-specific manner, RIα antisense, via efficient depletion of the growth stimulatory molecule RIα, induces growth inhibition, apoptosis, and phenotypic (cell morphology) changes, providing an innovative approach to combat hormone-insensitive prostate cancer cell growth.