Quantitative measurement of telomerase catalytic subunit (hTERT) mRNA in laryngeal squamous cell carcinomas

We tested 30 laryngeal squamous cell carcinomas (LSCCs) and 30 matched control laryngeal samples from the same patients for the presence of human telomerase catalytic subunit (hTERT) mRNA by using the Roche LightCycler Telo TAGGG hTERT Quantification kit. The hTERT index was calculated to express the relative quantity levels of hTERT mRNA. hTERT mRNA was detectable in 10 out of 30 (33%) laryngeal tissues covered by normal and/or reactively hyperplastic laryngeal epithelium and 23 out of 30 LSCCs (77%). The mean hTERT indices were 0.15 for control non-cancerous laryngeal samples, 0.57 for grade I, 2.35 for grade II and 3.72 for grade III LSCCs. LSCCs without detectable hTERT mRNA (23%) tended to have lower grades of disease. No correlation was found between the levels of hTERT mRNA and tumour size or locoregional lymph node status. We believe that hTERT mRNA in normal and/or reactively hyperplastic laryngeal epithelium originates from the stem cells and corresponds to the self-renewal capacity of the squamous epithelium. However, the greater quantity of h TERT mRNA in LSCCs is the result of telomerase reactivation in the process of laryngeal carcinogenesis.