BACKGROUND: RBBP6 is one of the genes identified as a proliferative gene that plays a role
in cancer development, On the other hand both RBBP6 and telomerase activity have been
shown to be increase in various cancers. E6 protein of HPV and RBBP6 is known to enhance
the progression of cancer cells by interacting with p53 and presenting it to be ubiquitinated
by the proteasome thereby promoting cell proliferation and preventing apoptosis. Studies
also show that HPV E6 protein can increase telomerase activity by activating the expression
of human telomerase reverse transcriptase (hTERT), thus enabling the immortalization of the
cells. With RBBP6 and hTERT showing a similar profile in cancer cells, we seek to
investigate any possible effect of RBBP6 on telomerase activity.
RESULTS: Using real-time qPCR and TRAPeze RT Telomerase detection kit (Merc) respectively. We used cervical cancer cell lines in which CaSki cell showed the reduction of hTERT
expression and reduction in telomerase activity significantly in RBBP6-knockdown cells.
While no significant changes were observed in HeLa cells. Real-time growth assay revealed
a significant drop in cell growth in co-silenced RBBP6 and hTERT cells substantiating our
observation that RBBP6 might be playing a role in cell proliferation.
CONCLUSION: Taken all together, the observed effect of RBBP6 gene silencing on telomerase
activity in cervical cancer is cell line dependent.