The most common solid
tumor is
testicular cancer among young men.
Bleomycin is an antitumor
antibiotic used for the
therapy of
testicular cancer. TRAIL is a proapoptotic
cytokine that qualified as an apoptosis inducer in
cancer cells. Killing
cancer cells selectively via apoptosis induction is an encouraging therapeutic strategy in clinical settings. Combination of TRAIL with chemotherapeutics has been reported to enhance TRAIL-mediated apoptosis of different kinds of
cancer cell lines. The molecular ground for sensitization of tumour cells to TRAIL by chemotherapeutics might involve upregulation of TRAIL-R1 (TR/1, DR4) and/or TRAIL-R2 (
TR/2, DR5) receptors or activation of proapoptotic
proteins including
caspases. The curative potential of TRAIL to eradicate
cancer cells selectively in
testicular cancer has not been studied before. In this study, we investigated apoptotic effects of
bleomycin, TRAIL, and their combined application in NTera-2 and NCCIT
testicular cancer cell lines. We measured
caspase 3 levels as an apoptosis
indicator, and TRAIL receptor expressions using flow cytometry. Both NTera-2 and NCCIT cells were fairly resistant to TRAIL's apoptotic effect. Incubation of
bleomycin alone caused a significant increase in
caspase 3 activity in NCCIT. Combined incubation with
bleomycin and TRAIL lead to elevated
caspase 3 activity in Ntera-2. Exposure to 72 h of
bleomycin increased TR/1,
TR/2, and TR/3 cell-surface expressions in NTera-2. Elevation in TR/1 cell-surface expression was evident only at 24 h of
bleomycin application in NCCIT. It can be concluded that TRAIL
death receptor expressions in particular are increased in
testicular cancer cells via
bleomycin treatment, and TRAIL-induced apoptosis is initiated.