Increased Copy Number of the TERT and TERC Telomerase Subunit Genes in Cancer Cells

The 2008 review article and accompanying studies discussed the increased copy number of the TERT and TERC telomerase subunit genes in cancer cells, which is frequently observed across various human cancers. The review and studies highlighted that this increase in gene dosage is associated with a growth advantage for cancer cells, potentially promoting oncogenesis through telomerase activity and possibly through other mechanisms independent of telomere lengthening. The TERT gene is located on chromosome 5p15.33 and TERC on 3q26.3, regions often involved in chromosomal gains in tumors. The document reported that increased hTERT copy number was found in 10 out of 15 cell lines and 17 out of 58 primary tumors, with varying percentages across different cancer types. It also noted that increased gene dosage may have clinical implications, potentially affecting outcomes and prognosis in cancer patients. The studies included in the document suggested that TERT and TERC amplification could contribute to cancer progression, particularly in lung and cervical carcinomas, and emphasized the need for further research to fully understand the consequences of telomerase up-regulation in cancer.