High bad and bcl-xL gene expression and combined bad, bcl-xL, bax and bcl-2 mRNA levels: molecular predictors for survival of stage 2 soft tissue sarcoma patients

Anticancer Res. 2002 May-Jun;22(3):1553-9.

Abstract

The role of the bcl-2 gene family members in promoting or antagonizing apoptosis in malignant tumors, including soft tissue sarcomas (STS), is well known. However, the impact of mRNA expression of bcl-2 family genes on prognosis has not been thoroughly investigated in STS. Samples from 82 STS patients were analyzed for mRNA expression of bad, bax, bcl-xL and bcl-2 by a high-throughput quantitative RT-PCR approach, using validated assays based on TaqMan technology. The mRNA data, related to glyceraldehyde-3-phosphate dehydrogenase expression measured in the same sample, were analysed for their correlation to tumor stage and overall survival of patients. In a Kaplan-Meier analysis none of the mRNA levels investigated differed significantly with regard to their impact on survival (log-rank test). However, after including the tumor stage in the statistical analysis, a borderline significance was observed for bad mRNA expression (p=0.068) indicating a stage-specific impact of mRNA expression on prognosis. Considering STS patients of tumor stage 2, multivariate Cox analysis revealed that bad mRNA values > or = 10 (p=0.0039; RR=9.08), bcl-xL > or = 1.5 (p=0.067; RR=4.59), bax > or = 0.005 (p=0.1; RR=2.84) and bcl-2 < 3 (p=0.42; RR=1.7) were associated with a poor prognosis. Combined high bad/bcl-xL mRNA expression levels revealed a 20-fold increase in the relative risk of tumor-related death (p=0.016) when comparing the poor and good prognosis groups. There was a 14.5-fold and 6.5-fold increase in the risk for the combinations of high bax/bcl-xL mRNA (p=0.018) and bax/bcl-2 mRNA expression (p=0.017), respectively. In conclusion, high bad mRNA levels and combined values of bad/bcl-xL bax/bcl-xL and bax/bcl-2 appear to be independent prognostic factors at least for stage 2 STS patients. In the combinations of mRNA levels there was more than an additive effect pointing to different pathways of prognostic relevance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Carrier Proteins / biosynthesis
  • Carrier Proteins / genetics
  • Gene Expression
  • Humans
  • Neoplasm Staging
  • Prognosis
  • Proto-Oncogene Proteins / biosynthesis
  • Proto-Oncogene Proteins / genetics
  • Proto-Oncogene Proteins c-bcl-2 / biosynthesis*
  • Proto-Oncogene Proteins c-bcl-2 / genetics
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / genetics
  • Sarcoma / genetics
  • Sarcoma / metabolism*
  • Sarcoma / pathology
  • Soft Tissue Neoplasms / genetics
  • Soft Tissue Neoplasms / metabolism*
  • Soft Tissue Neoplasms / pathology
  • bcl-2-Associated X Protein
  • bcl-Associated Death Protein
  • bcl-X Protein

Substances

  • BAD protein, human
  • BAX protein, human
  • BCL2L1 protein, human
  • Carrier Proteins
  • Proto-Oncogene Proteins
  • Proto-Oncogene Proteins c-bcl-2
  • RNA, Messenger
  • bcl-2-Associated X Protein
  • bcl-Associated Death Protein
  • bcl-X Protein