Telomerase as a tool for the differential diagnosis of human hepatocellular carcinoma

Abstract

An incremental positivity of telomerase was observed during hepatocarcinogenesis. The use of this assay in 21-G-needle biopsy specimens may be useful in clinical examination.

In Situ Telomeric Repeat Amplification Protocol (TRAP) Detecting Telomerase Activity in Human Hepatocellular Carcinoma.

“…PCR ELISA protocols were used to examine the enzyme activity in the homogenized tissue [12,15], while in situ hybridization was utilized to check the telomerase mRNA on tissue sections [5,20]. Though in situ TRAP assay in detecting telomerase activity on cells was developed recently [6,17], there is no report on telomerase activity in cryostat liver tissue sections so far.…”

“…Telomerase is one of the key enzymes in providing the cells with constant proliferation capability, so it is related with the acquirement or maintenance of the malignant characters [4,10]. There is a significant increase of the telomerase activity in certain kinds of animal and human malignancies including liver cancer [2,8,12,15]. Unfortunately, most data were based upon results of PCR of homogenized tissue or cell cultures [2], or the examination of telomerase mRNA of cells and tissue sections [5,20].…”

Identification of serum anti-human telomerase reverse transcriptase (hTERT) auto-antibodies during progression to hepatocellular carcinoma

“…On the other hand, although the OD of anti-hTERT antibodies in patients with LC tended to be lower than that of patients with HCC, the difference was not significant. A previous study, did not detect telomerase activity in most patients with LC or CH, but did identify the activity in several patients without cancer (12.5 -42.1%) (Nouso et al, 1996;Kitamoto and Ide, 1999). Conceivably, some regenerative precancerous hepatic nodules or some populations of clonally expanded cells already had telomerase activity even at the LC stage, and this could have induced the immune responses against hTERT.…”

“…In a number of malignant tumors such as hepatocellular carcinoma, colon carcinoma, cervical carcinoma or certain leukemia, the progression of disease has been reported to clearly correlate with the extent of telomerase activity (Nakayama et al, 1998;Kojima et al, 1997;Nouso et al, 1996;Kitamoto and Ide, 1999;Kolquist et al, 1998). Therefore, it would be important to investigate whether the progression of a malignant disease correlates with the amount of hTERT auto-antibodies.…”

“…The difference of optical density (OD) between the patients with HCC and patients with CH was significant. Since the amount of positive telomerase activity increased during hepatocarcinogenesis, we concluded that the significantly increased levels of antihTERT were due to the hTERT expression level (Nakayama et al, 1998;Kojima et al, 1997;Nouso et al, 1996). On the other hand, although the OD of anti-hTERT antibodies in patients with LC tended to be lower than that of patients with HCC, the difference was not significant.…”