The Expressions And Clinical Significances Of MyoD1 And MYOGENIN In Rhabdomyosarcomas Of Childhood

Objective: To investigate the expression of MyoD1,Myogenin in rhabdomyosarcoma and other small cell malignant tumors of childhood,and approach the clinical significance.Methods: To collect 46 paraffin wax specimens of surgical exairesis'tissue. Experiment group, including 11 cases of Embryonal rhabdomyosarcoma, 5 cases of alveolar rhabdomyosarcoma; Control group , 10 cases of neuroblastoma,malignant lymphoma,Ewing's sarcoma.Slicing conventionally, dyeing by HE, and repeated checking all specimens cohere with clinical datas. To detect the expression levels of the proteins of MyoD1,Myogenin by S-P immunohistochemistry method in 4 types of small cell malignant tumors,including rhabdomyosarcoma, neuroblastoma, malignant lymphoma, Ewing's sarcoma.Results: (1) In 46 detected specimens, MyoD1 and myogenin have been expressed in different level in 2 types of rhabdomyosarcoma, but the negative expression rates other 3 types of small cell malignant tumors. The positive expression rate and intensity of MyoD1 and myogenin in rhabdomyosarcoma group are higher than them in other 3 types of small cell malignant tumors,obviously(P<0.05). (2) The positive expressions of MyoD1 and myogenin in rhabdomyosarcoma :75%,68.75%; The expressions of these 2 proteins in rhabdomyosarcoma are not obvious differences (P>0.05). (3) The positive strong expressions of MyoD1 and myogenin in rhabdomyosarcoma: 50%,50%; The strong expressions of these 2 proteins in rhabdomyosarcoma are not obvious differences (P>0.05).(4)The positive expressions of MyoD1 in embryonal rhabdomyosarcoma and alveolar rhabdomyosarcoma: 63.64%,100%; The positive expressions of myogenin in embryonal rhabdomyosarcoma and alveolar rhabdomyosarcoma : 54.55%,100%. The positive expression rate and intensity of these 2 proteins in 2 types of rhabdomyosarcoma are obvious differences (P<0.05). (5) The strong positive expressions of MyoD1 in embryonal rhabdomyosarcoma and alveolar rhabdomyosarcoma: 45.45%,60%; The strong positive expressions of myogenin in embryonal rhabdomyosarcoma and alveolar rhabdomyosarcoma:27.27 %,100%. The positive expression rate and intensity of MyoD1 in 2 types of rhabdomyosarcoma are not obvious differences (P>0.05); The positive expression rate and intensity of myogenin in 2 types of rhabdomyosarcoma are obvious differences (P<0.05). (6)The positive expression of MyoD1 and myogenin in rhabdomyosarcoma of different malignant levels (the histological classify) : I stage rhabdomyosarcoma group (7 cases): 57.14%,42.86%;II stage rhabdomyosarcoma group (4 cases): 75%,75%; III stage rhabdomyosarcoma group(5 cases): 100%,100%.More High maglinant level, higher the positive expressions of MyoD1 and myogenin (P<0.05). (7)The positive expression of MyoD1 and myogenin in rhabdomyosarcoma of different prognosis (the new IRS typing) : the middle prognosis group (11 cases): 63.64%,54.55%, the bad prognosis group (5 cases): 100%,100%.The expression of MyoD1and myogenin is obviously correlated with the progosis of rhabdomyosarcoma; The positive expressive rates of these 2 types of proteins in bad prognosis group are higher than them in middle prognosis group (P<0.05).Conclusions: (1)The obvious expressive difference of MyoD1 and myogenin in rhabdomyosarcoma and other 3 types of small cell malignant tumor can be indexs that distinguish rhabdomyosarcoma with other mall cell malignant tumors. (2) The expression of MyoD1 and myogenin in rhabdomyosarcoma are not obvious differences. (3) MyoD1 and myogenin can be the combination index of auxiliary diagnosis in rhabdomyosarcoma, providing significant and additional molecular biological methods to pathological diagnosis. (4) MyoD1 and myogenin can be the molecular biological indexs that distinguish embryonal rhabdomyosarcoma with alveolar rhabdomyosarcoma. (5)The expressions of MyoD1 and myogenin in different maglinant levels rhabdomyosarcoma are different. More High maglinant level, higher the positive expression of MyoD1 and myogenin; To detect the expression levels of the proteins of MyoD1 and myogenin in rhabdomyosarcoma of childhood have clinical guide significance for decision of maglinant level in rhabdomyosarcoma of childhood. (6) The expressions of MyoD1 and myogenin in rhabdomyosarcoma of different prognosis are different. More bad prognosis it is, higher the positive expression of MyoD1 and myogenin; To detect the expression levels of the proteins of MyoD1 and myogenin in rhabdomyosarcoma of childhood have invariable clinical guide significance for decision of rhabdomyosarcoma's prognosis of childhood .