Lepelley P, Poulain S, Grardel N, Preudhomme C, Cosson A, Fenaux P
Laboratorie d'Hematologie, CHU Lille, France.
Leuk Lymphoma. 1998 May;29(5-6):547-51. doi: 10.3109/10428199809050914.
The major vault lung resistance protein LRP is a cytoplasmic protein involved in drug resistance, especially in acute myeloid leukemia. We looked for LRP overexpression, using immunocytochemistry with LRP 56 monoclonal antibody, on marrow slides from 41 cases of myelodysplastic syndromes (MDS). LRP overexpression (LRP+) was defined by expression of LRP 56 in at least 20% of marrow blasts. LRP overexpression was seen in 19 (46%) cases. Concordant results between LRP overexpression and P-glycoprotein (PGP) expression were seen in 66% of the cases (p = 0.03), and discordant results (LRP+ and PGP-, or LRP- and PGP+) in 33% of the cases. No correlation was seen between LRP overexpression and FAB type, karyotype, CD34, p53 expression and bcl2 overexpression in blasts. Furthermore, in the 18 cases treated with anthracycline-AraC intensive chemotherapy and the 7 cases treated with low dose AraC, the response rate was not significantly different in LRP+ and LRP- patients. Survival was also similar in LRP+ and LRP- patients. In conclusion, LRP overexpression is probably more frequent in MDS than in de novo AML and, as in AML, is only partially correlated with PGP expression. In our experience, however, LRP was not a prognostic factor for response to chemotherapy and survival in MDS.
主要穹窿体肺耐药蛋白LRP是一种参与耐药的胞质蛋白，尤其在急性髓系白血病中。我们使用LRP 56单克隆抗体免疫细胞化学方法，在41例骨髓增生异常综合征（MDS）患者的骨髓涂片上检测LRP过表达情况。LRP过表达（LRP+）定义为至少20%的骨髓原始细胞中LRP 56表达。19例（46%）出现LRP过表达。66%的病例中LRP过表达与P-糖蛋白（PGP）表达结果一致（p = 0.03），33%的病例结果不一致（LRP+且PGP-，或LRP-且PGP+）。LRP过表达与FAB分型、核型、CD34、p53表达及原始细胞中bcl2过表达之间均无相关性。此外，在接受蒽环类-阿糖胞苷强化化疗的18例患者及接受小剂量阿糖胞苷治疗的7例患者中，LRP+和LRP-患者的缓解率无显著差异。LRP+和LRP-患者的生存率也相似。总之，LRP过表达在MDS中可能比在初发急性髓系白血病中更常见，并且与AML一样，仅部分与PGP表达相关。然而，根据我们的经验，LRP不是MDS患者化疗反应和生存的预后因素。
