A lymphoproliferative disorder (LPD) is a medical condition that is characterized by the dysfunction of the immune system, often resulting in excessive production of lymphocytes or white blood cells. Many cases of LPDs originate from inherited conditions, and sometimes they are caused by acquired immune system dysfunction. The RNA-dependent DNA polymerase, telomerase, is essential in regulating telomere length by acting as a reverse transcriptase. The majority of human somatic tissues do not display telomerase activity, whereas human tumors demonstrate increased telomerase expression, suggesting an increase in its activity. To maintain telomeres, cells with highly proliferative capacity express telomerase, thus maintaining their length.
Materials and methods
We used quantitative real-time reverse transcriptase PCR on total RNA to determine the expression of telomerase reverse transcriptase (hTERT) mRNA and GAPDH (RNA, as reference gene) in blood of 38 cases having different LPDs, including leukemia and disseminated lymphomas, and 17 age-matched and sex-matched healthy individuals.
The present investigation showed that the relative telomerase mRNA expression levels of the patient groups (acute lymphocytic leukemia, chronic lymhocytic leukemia, and non-Hodgkin lymphomas) were significantly higher than those of the control group (P=0.02, 0.002, 0.02), respectively, with the highest value in the chronic lymhocytic leukemia group.
The usefulness of hTERT mRNA expression as a tumor marker in LPDs was shown. Therefore, blood hTERT mRNA is a novel and available marker for LPD diagnosis.