Correlation between p38 mitogen-activated protein kinase and human telomerase reverse transcriptase in sarcomas

We investigated 36 soft tissue malignant fibrous histiocytomas (MFH), 24 liposarcomas (LS) and 9 bone MFH samples for hTERT and p38 MAPK expression. Quantitative detection of hTERT and p38 MAPK was performed by RT-PCR.There was a significant positive correlation between the values of hTERT and p38 MAPK in all samples (r = 0.445, p = 0.0001), soft tissue MFH (r = 0.352, p = 0.0352), LS (r = 0.704, p = 0.0001) and bone MFH samples (r = 0.802, p = 0.0093). Patients who had a higher than average expression of p38 MAPK had a significantly worse prognosis than other patients (p = 0.0036).p38 MAPK may play a role in up-regulation of hTERT, and therefore, p38 MAPK may be a useful marker in the assessment of hTERT and patients' prognosis in sarcomas.Telomerase, an enzyme related to cellular immortality, stabilizes telomere length by adding DNA repeats onto telomere ends [1,2]. Many studies have revealed that telomerase activity is expressed in many different types of carcinomas, detected in more than 85% of the human carcinoma samples, and it has been found to be useful as a prognostic indicator [3-5]. Telomerase activity is mainly regulated by human telomerase reverse transcriptase (hTERT), which is the catalytic subunit of telomerase [6,7]. Also, hTERT has been significantly detected in many types of sarcoma samples, and previous reports have indicated that hTERT expression is associated with tumor aggressiveness, feature and clinical outcome in sarcomas [8-14]. Therefore, hTERT may play an important role in telomere maintenance mechanisms in human sarcomas. However, it is notable that thus far, there has been no clear understanding of the mechanisms of hTERT expression especially in sarcomas. p38 is a mitogen-activated protein kinase (MAPK) activated by phosphorylation on serine/threonine residue when cells are exposed to cellular stress, and has a wide variety of biological functions [15-17]. Recent studies have suggested that signals transmitted through MAP kinase can i