Silent information regulator type-1 (SIRT1) is the best-studied member of the Sirtuin (Sir2) family of nicotinamide dinucleotide (NAD)-dependent class III histone deacetylases (HDACs). Rrecently, it is suggested that SIRT1 may be involved in the development of malignant tumors including mouse lymphoma, but has not yet been explored in Angioimmunoblastic T-cell lymphoma (AITL). Therefore, we investigated the prevalence and the prognostic impact of SIRT1 expression in AITL. Immunohistochemical expression of SIRT1, p53 were evaluated by using a 2 mm core from 45 AITL patients. Positive expression of SIRT1 was seen in 71.11% (32 of 45) of patients and p53 expression were seen in 53.33% (24 of 45). SIRT1 and p53 expression were significantly associated with shorter PFS by univariate analysis (P=0.009 and P < 0.001, respectively), multivariate analysis also shows that SIRT1 expression relate to worse prognosis. We also suggest inferior survival in AITL with the combined expression of SIRT1 and clinical characteristics of high IPI scores, high clinical stage, increased serum LDH, decreased HGB and increased γ-Globulin. In conclusion, our results indicate that SIRT1 is strongly expressed in AITL and it act as a clinically significant prognostic indicator for AITL patients, may also serve as a therapeutic target in AITL.
Keywords: AITL; SIRT1; prognosis; tumor; tumorigenesis.