The prognostic role of PRUNE2 in leiomyosarcoma.

PRUNE2 plays an important role in regulating tumor cell differentiation, proliferation, and invasiveness in neuroblastoma. Our previous study revealed that PRUNE2/OBSCN two-gene relative expression classifer accurately differentiated leiomyosarcoma from gastrointestinal stromal tumor. However, the association between PRUNE2 expression and prognosis in leiomyosarcoma is poorly understood. In this study, we evaluated the prognostic role of PRUNE2 in leiomyosarcoma. PRUNE2 expression was detected using immunohistochemistry in 30 formalin-fixed, paraffin-embedded leiomyosarcoma tissues from MD Anderson Cancer Center, and high expression was detected in 36.7% (11/30) of the samples. To validate these results, immunohistochemistry was performed on another cohort of 45 formalin-fixed, paraffin-embedded leiomyosarcoma tissues from Tianjin Medical University Cancer Institute & Hospital, and high PRUNE2 protein expression was detected in 37.8% (17/45) of the samples. Moreover, elevated PRUNE2 expression was significantly associated with tumor size (P = 0.03) and hemorrhage/cyst (P = 0.014), and was an independent favorable prognostic factor for overall survival in leiomyosarcoma patients from Tianjin Medical University Cancer Institute & Hospital (P < 0.05). These data suggest that increased PRUNE2 protein expression may serve as a favorable prognostic marker in human leiomyosarcoma.