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PTPL1 and PKC? contribute to proapoptotic signalling in prostate cancer cells.

ABSTRACT: PTPL1 is a non-receptor protein tyrosine phosphatase involved in apoptosis regulation, although controversial findings have been reported in different cancer types. We report here a proapoptotic role for PTPL1 in PC3 and LNCaP prostate cancer cells, as its absence induces apoptosis resistance upon treatment with different drugs. In PC3 cells, PTPL1 silencing by small interfering RNA influences the expression levels of Bcl-xL and Mcl-1(S) proteins as well as final events in the apoptotic process such as activation of caspases and caspase-mediated cleavage of proteins like Mcl-1 or poly (ADP-ribose) polymerase. We have identified PKC? as an intermediary of PTPL1-mediated apoptotic signalling and that phosphorylation status of NF-?B and I?B? is influenced by PTPL1 and PKC?. Furthermore, the loss of PTPL1 and PKC? expression in poorly differentiated, more aggressive human prostate cancers also indicate that their absence could be related to apoptosis resistance and tumour progression.

SUBMITTER: Castilla C

PROVIDER: S-EPMC3668626 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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PTPL1 and PKCδ contribute to proapoptotic signalling in prostate cancer cells.

Castilla C C Chinchón D D Medina R R Torrubia F J FJ Japón M A MA Sáez C C

Cell death & disease 20130404

PTPL1 is a non-receptor protein tyrosine phosphatase involved in apoptosis regulation, although controversial findings have been reported in different cancer types. We report here a proapoptotic role for PTPL1 in PC3 and LNCaP prostate cancer cells, as its absence induces apoptosis resistance upon treatment with different drugs. In PC3 cells, PTPL1 silencing by small interfering RNA influences the expression levels of Bcl-xL and Mcl-1(S) proteins as well as final events in the apoptotic process ...[more]

PMID: 23559010

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