A Systematic Analysis Of SOX11 Expression In Epithelial And Nonepithelial Tumors And Its Implication In Surgical Pathology

Background and Aims: SOX11 is an essential transcription factor functioning as a neurogenesis regulator.By far,SOX11 has been suggested as a diagnostic marker as well as oncogene considering its distinct expression in mantle cell lymphoma(MCL).However,SOX11 expression in other tumors has not been fully understood yet.In this study,we aimed to detect the expression of SOX11 in neuroectodermal,germ cell,mesenchymal,and epithelial tumors,and further evaluate the role of SOX11 as a potential biomarker for diagonosis and differential diagnosis of cancer.Methods: SOX11 expression were detected by immunohistochemistry(IHC)with an autostainer(DAKO Autostainer Link 48)in 2026 paraffin samples of neuroectodermal,germ cell,mesenchymal,and epithelial tumors and normal control tissues,which were obtained from Department of Pathology,Tongji Hospital of Tongji Medical College,Huazhong University of Science and Technology.IHC staining for SOX11 was scored as follows: the multiplication of the intensity of staining(0 negative;1+ weak;2+ moderate;3+ strong)and the percentage of positive tumor cells,which resulted in a score of 0 to 300.A score <10 was identified as 0(cutoff value <10),10-40 as 1+,41–140 as 2+,and 141–300 as 3+.Results: Positive staining of SOX11 was detected in all neuroectodermal tumors with neural differentiation and in immature teratomas revealing neurogenesis.Less frequently,SOX11 was only expressed in 50% of astrocytomas and 24% of malignant peripheral nerve sheath tumors(MPNSTs),most of which were sporadic and weak/intermediate.In epithelial tumors,distinct SOX11 expression was identified in 97% of salivary ductal carcinomas(SDCs)and a variety of high-grade neuroendocrine carcinomas(NECs),especially the small cell lung carcinomas(SCLCs)(68%),but was absent in most other carcinomas,except for less and/or focal and weak expression in adenocarcinomas from the lung,genital tract,and breast,and salivary adenoid cystic carcinomas(ACCs)and epithelial-myoepithelial carcinomas(EMCs).In mesenchymal tumors,besides MCLs,prominent positive staining of SOX11 was detected in 90% of rhabdomyosarcomas(RMS),and all myxiod/round cell liposarcoma(MRCLs).Less frequent and/or focal and weak expression was confirmed in lymphoblastic,Burkitt and follicular lymphomas(BL and FL),synovial sarcoma(SS)and angiosarcoma(AS).Conclusions: Since high expression of SOX11 was evident in neuroectodermal tumors with neural differentiation,high-grade NECs,SDCs,RMS,and MRCLs,SOX11 should be fully taken into account by the pathologists when diagnosing and differential diagnosing these tumors.It is notable that the highly sensitive and specific SOX11 expressions in SDCs and MRCLs make it a potential diagnostic marker for these two kinds of tumors,which is believed to display attractive application prospects for future pathological diagnosis.