SPAG9 and nonpapillary renal cell carcinoma: In recent years, research on the role of SPAG9 in tumors has mainly focused on its role in promoting tumor progression [49], but our study found that SPAG9 expression was significantly associated with good prognoses in ccRCC, a result that has not been found in other cancer types and contradicts the widely recognized cancer-promoting role of SPAG9.