Part:BBa_K1722001

Telomerase reverse transcriptase (abbreviated to TERT, or hTERT in humans) is a catalytic subunit of the enzyme telomerase, which, together with the telomerase RNA component (TERC), comprises the most important unit of the telomerase complex. The telomerase is a ribonucleoprotein enzyme to which multiple functions have been attributed, the most important of these is the maintenance of the telomere which is related with cellular immortalization and cancer. 85% of human tumors have telomerase activity, that in normal cells goes undetected. These characteristics make the telomerase an attractive target for chemotherapy. TERT promoter mutations were highly frequent in glioblastoma (83.9%), urothelial carcinoma (64.5%), oligodendroglioma (70.0%), medulloblastoma (33.3%) and hepatocellular carcinoma (31.4%). C228T and C250T were the most common mutations. In urothelial carcinoma, several novel rare mutations were identified. TERT promoter mutations were absent in gastrointestinal stromal tumour (GIST), thymic epithelial tumours, gastrointestinal leiomyoma, gastric schwannoma, cholangiocarcinoma, gastric and pancreatic cancer. TERT promoter mutations highly correlated with upregulated TERT mRNA expression and telomerase activity in adult gliomas. These mutations differentially enhanced the transcriptional activity of the TERT core promoter.TERT promoter mutations are frequent in multiple tumour types and have similar distributions in Chinese cancer patients. The functional significance of these mutations reflect the importance to telomere maintenance and hence tumourigenesis, making them potential therapeutic targets. More importantly , we mutate the normal TERTp into a new TERTp with high-efficency of the promotion so as to make our system work efficiently. In the experiment, we change 4 base of the TERTp gene. Eventually, The telomerase reverse transcriptase promoter can specifically promotes with the identification of telomerase reverse transcriptase, which means it can only promote in cancer cells. In our system, we use TERTp to promote only in cancer cells. Together with bladder-specific hUPII promoter we can achieve the precision of system’s work in bladder cancer cells.  In our experiment, we constructed three and two plasmids before and after two times to verify the function using high-efficency TERTp.The TERTp can be used to promote in cancer cells. Similar to our system, alike synthesizing gene circuits are also expected to be one of the promising approaches to the treatment to other cancer.