***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Purpose : Bcl-2 is antiapoptotic , and its overexpression has been associated with resistance to and rogen deprivation and poor outcome in some patients treated with radiotherapy .  Bax is proapoptotic , regulating Bcl-2 through heterodimer formation . In a prior study , Bcl-2 and Bax were not related to outcome in locally advanced patients treated with radiotherapy or short-term and rogen deprivation + radiotherapy ( STAD+RT )  on another Radiation Therapy Oncology Group trial ( 86 - 10 ) . A follow-up investigation was carried out here in more contemporary high-risk men treated on Radiation Therapy Oncology Group 92 - 02 with STAD+RT or long-term AD+RT ( LTAD+RT ) .  Experimental Design : Adequate tissue was available to be analyzed immunohistochemically in 502 patients for Bcl-2 and 343 patients for Bax . Univariate and multivariate analyses by Cox proportional hazards models were applied to end points of failure . Results : Bcl-2 was positive in 45.6 % cases , and Bax expression altered in 53.9 % cases . Abnormal Bcl-2 was not related to any of the failure end points tested . Altered Bax expression was significantly associated with any failure ( P = 0.023 ) and marginally with biochemical failure ( P = 0.085 ) . The combination of negative Bcl-2/normal Bax expression seemed more robust , being significantly related to reduced biochemical failure ( P = 0.036 ) and any failure ( P = 0.046 ) . The predictive value of negative Bcl-2/normal Bax was most pronounced in those who received STAD+RT , as opposed to LTAD+RT . Conclusions : Normal Bax expression was associated with significantly more favorable outcome . The combination of negative Bcl-2 and normal Bax was more consistently significant , particularly when STAD+RT was the treatment administered . These data suggest that LTAD+RT should be used when either Bcl-2 or Bax is abnormally expressed 
    Output:
    
Although this meta- analysis was based on data abstract ed from observational studies , our results may justify the use of risk-adapted therapeutic strategies for AL according to the Bcl-2 expression status