The influence of compound aITEL1296 on telomerase activity and growth of cancer cells

Telomerase is a ribonucleoprotein complex, which synthesizes telomeric repeats and which has been identified as a promising target for anticancer therapy. Here we have investigated the effect of a new compound aITEL1296 on telomerase activity. aITEL1296 effectively inhibited telomerase activity; its inhibitory activity was a bit higher (IC 50 = 0.19 ± 0.02 ng/mL) than that of BIBR1532, one of the most potent telomerase inhibitors known to date. In addition to telomerase inhibition aITEL1296 activated apoptotic mechanisms and effectively suppressed proliferation of tumor cell lines (GI 50 = 5.0 ± 0.2 ng/mL for most sensitive cell line LnCap) but not normal fibroblast cell line. © Pleiades Publishing, Ltd., 2012

The influence of compound aITEL1296 on telomerase activity and growth of cancer cells

Telomerase is a ribonucleoprotein complex, which synthesizes telomeric repeats and which has been identified as a promising target for anticancer therapy. Here we have investigated the effect of a new compound aITEL1296 on telomerase activity. aITEL1296 effectively inhibited telomerase activity; its inhibitory activity was a bit higher (IC 50 = 0.19 ± 0.02 ng/mL) than that of BIBR1532, one of the most potent telomerase inhibitors known to date. In addition to telomerase inhibition aITEL1296 activated apoptotic mechanisms and effectively suppressed proliferation of tumor cell lines (GI 50 = 5.0 ± 0.2 ng/mL for most sensitive cell line LnCap) but not normal fibroblast cell line. © Pleiades Publishing, Ltd., 2012

Apoptotic endonuclease EndoG induces alternative splicing of telomerase catalytic subunit hTERT and death of tumor cells

Telomerase activity is known to be regulated by alternative splicing of its catalytic subunit hTERT (human Telomerase Reverse Transcriptase) mRNA. Induction of non-active spliced hTERT leads to inhibition of telomerase activity. However, very little is known about the mechanism of hTERT mRNA alternative splicing. The aim of this study was to determine the role of apoptotic endonuclease EndoG in alternative splicing of hTERT and telomerase activity. Strong correlation was found between expression of EndoG and hTERT splice-variants in 12 colon cancer cell lines. Overexpression of EndoG in СаСо-2 cells downregulated the expression of active full-length hTERT variant and upregulated non-active spliced variant. Reduction of full-length hTERT caused downregulation of telomerase activity, dramatically shortening of telomeres length during cell divisions, converting cells to the replicative senescence state, activation of apoptosis and finally cell death. These data indicated the participation of EndoG in alternative splicing of mRNA of telomerase catalytic subunit, regulation of telomerase activity and cell fate. © 2016, Pleiades Publishing, Ltd

Apoptotic endonuclease EndoG induces alternative splicing of telomerase catalytic subunit hTERT and death of tumor cells

Telomerase activity is known to be regulated by alternative splicing of its catalytic subunit hTERT (human Telomerase Reverse Transcriptase) mRNA. Induction of non-active spliced hTERT leads to inhibition of telomerase activity. However, very little is known about the mechanism of hTERT mRNA alternative splicing. The aim of this study was to determine the role of apoptotic endonuclease EndoG in alternative splicing of hTERT and telomerase activity. Strong correlation was found between expression of EndoG and hTERT splice-variants in 12 colon cancer cell lines. Overexpression of EndoG in СаСо-2 cells downregulated the expression of active full-length hTERT variant and upregulated non-active spliced variant. Reduction of full-length hTERT caused downregulation of telomerase activity, dramatically shortening of telomeres length during cell divisions, converting cells to the replicative senescence state, activation of apoptosis and finally cell death. These data indicated the participation of EndoG in alternative splicing of mRNA of telomerase catalytic subunit, regulation of telomerase activity and cell fate. © 2016, Pleiades Publishing, Ltd