Telomerase subunit immunoreactivity and recurrence in colorectal cancer

BACKGROUND/AIMS: Telomerase is expressed in human germ tissues and in the majority of primary human tumors. The catalytic subunit of telomerase, hTERT is one of the most important components of telomerase. In this study we attempted to show by means of immunohistochemistry the association between hTERT expression and recurrence in 128 colorectal cancer patients surgically treated in the University of Tokyo Hospital. METHODOLOGY: Immunostaining was performed in a conventional manner using a commercial monoclonal antibody. RESULTS: In our results, negative TERT immunoreactivity in the primary lesion was significantly associated with advanced tumor stage (p=0.0007), the presence of lymph node metastasis (p=0.00018) and recurrence (p<0.0001). Recurrence-free survival rate was significantly lower in patients with negative TERT immunoreactivity (p=0.0002). In the same way, if limited in patients without metastatic lymph nodes at surgery or in patients with T3 or T4 tumor, the recurrence-free survival rate was significantly lower in those with negative TERT immunoreactivity (p=0.019, p=0.016). CONCLUSIONS: Negative TERT immunoreactivity may be a novel indicator for poor prognosis of colorectal cancer patients and additional studies with a larger number of patients may lead to identifying patients at high risk for recurrence more accurately.