The Expression And Value Of Caveolin-3 In Rhabdomyosarcomas

Rhabdomyosarcomas are one of the most common tumors of soft tissue,they are composed of various stages of rhabdomyoblasts,often occurring in children under 15 years of age.Based on histological and genetic characters,rhabdomyosarcomas are classified into three types: embryonal rhabdomyosarcoma(including spindle rhabdomyosarcoma, botryoid rhabdomyosarcoma,anaplastic rhabdomyosarcoma),alveolar rhabdomyosarcoma and pleomorphic rhabdomyosarcoma.The tumors are mainly constituted of various stages cells in the development of muscle, which are polymorphic and differentiated badly.Rhabdomyosarcomas need to be differentiated from some small round cell tumors and spindle cell tumors.Caveolin-3 is one member of caveolin family and is the only muscle special molecule,which was cloned and indentified in 19960 Some studies have shown that caveolin-3 play an important role in many signal transduction,it's loss and elevated expression has been associated with some muscular dystrophy disease.But there are less studies about the relationship bewteen caveolin-3 and tumors.In the current study,we investigated caveolin-3 expression in rhabdomyosarcomas and other soft tissue tumors which need to be differentiated from RMS.We compare caveolin-3 to desmin and myoD1 of clinical marker,and discuss the value of clinical diagnosis and differential diagnosis.Materials and methods1 Materials:Test to collect 20 cases,including 16 ERMS,1 ARMS,3 PRMS.Additionally,to collect 30 cases of other soft tissue tumors, includingleiomyosarcoma,synoviosarcoma,primitive neuroectodermal tumor,fibrosarcoma,malignant fibrous histiocytoma,each for 6 cases.2 Methods:SP immunohistochemical staining methods and in situ hybridization were used to detect the expression of caveolin-3 in RMS and other soft tissue tumors.SP immunohistochemical staining methods were used to detect the protein expression of desmin and myoD1 in RMS.Results1 In the SP immunohistochemistry,positive staining of caveolin-3 was seen in 16 of 20cases of RMS(80.0%),all other soft tissue tumors were negative(0/30),the expression pattern between RMS and other soft tissue tumors had statistical difference(P＜0.05).2 In the in situ hybridization,positive staining of caveolin-3 was seen in the 13 of 15(86.7%)cases of RMS,2 of 26(7.7%)cases of other soft tissue tumors.The expression pattern between RMS and other soft tissue tumors had statistical difference(P＜0.05).3 In the SP immunohistochemistry,positive staining of desmin.myoD1 were seen in 16 of 19 cases of RMS(84.2%).17 of 19 cases of RMS (89.5%)seperately,which had no statistical difference compared to caveolin-3(P＞0.05).4 Microscopy,caveolin-3 and desmin are positive in the more mature tumor cells,while myoD1 are mainly expressed in the primitive cellsConclusions1 caveolin-3 has the value of clinical diagnosis and differential diagnosis,and is highly sensitive and specific for RMS.2 caveolin-3 had no statistical difference compared to desmin,myoD1 in RMS,It may be a useful immunohistochemical marker in the clinical diagnosis of RMS.3 we combined caveolin-3,desmin,myoD1,the positive staining of RMS can get 95%(19/20),in which at least one antibody is positive,so combination application can improve diagnostic efficiency.