ABSTRACT
ObjectiveTo explore the co-expression of PTBP1 and p-AXL in osteosarcoma and its clinicopathological significance for prognosis evaluation. MethodsThe expression of PTBP1 and AXL and their prognostic value in osteosarcoma were analyzed by GEO and Target data. Paraffin biopsy specimens and clinical information from 76 cases of osteosarcoma and 37 cases of non-malignant bone tissue （callus， osteofibrous dysplasia and osteoid ostema） were obtained from the First Affiliated Hospital of Sun Yat-sen University from March 2016 to October 2020. The expressions of PTBP1 and p-AXL proteins in osteosarcoma were detected by immunohistochemistry. ResultsGEO database showed that the expression levels of PTBP and AXL in osteosarcoma tumor group were higher than those in normal tissues， but did not reach statistical significance. Target database showed that the high expression of PTBP1 had shorter Overall survival（OS） and Progression-free survival（PFS） than low PTBP1 expression， but did not reach statistical significance （P=0.064； P=0.134）. Immunohistochemical staining included 76 cases of osteosarcoma and 37 cases of non-malignant bone tissue. The expression rate of PTBP1 and p-AXL protein in osteosarcoma tissues was higher than that in non-malignant bone tissue. The expression of p-AXL is correlated with lung metastasis （P=0.025）. Kaplan-Meier analysis showed that lung metastasis， recurrence， PTBP1 expression， co-expression of PTBP1/p-AXL influence the prognosis of patients in OS. Multivariate Cox regression analysis showed that lung metastasis （P<0.000 1） and positive expression of PTBP1 （P=0.041） were independent risk factors for osteosarcoma patients in OS. Co-expression of PTBP1 and p-AXL had shorter OS （P=0.017） and PFS （P=0.043） than non-coexpression osteosarcoma patients. ConclusionsPTBP1 and p-AXL were highly expressed in osteosarcoma tissues. The co-expression of PTBP1 and p-AXL was associated with poor prognosis of patients， and PTBP1 could be used as an independent prognostic indicator of patients with osteosarcoma.