Zha Hongbin, Raffeld Mark, Charboneau Lu, Pittaluga Stefania, Kwak Larry W, Petricoin Emanuel, Liotta Lance A, Jaffe Elaine S
Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Lab Invest. 2004 Feb;84(2):235-44. doi: 10.1038/labinvest.3700051.
Overexpression of Bcl-2 protein has been known to play a role in the pathogenesis of follicular lymphoma (FL). However, 10-15% of FLs are negative for Bcl-2 by immunohistochemistry, raising the possibility that another gene product(s) may provide prosurvival signal(s). We used reverse phase protein microarray to analyze lysates of follicle center cells isolated by laser capture microdissection from: Bcl-2+ FL, Bcl-2- FL and reactive follicular hyperplasia (FH) (nine cases each group). TUNEL assay confirmed similar and reduced levels of apoptosis in Bcl-2+ FL and Bcl-2- FL, indicating the likelihood of Bcl-2-independent inhibition of apoptosis. Arrays were quantitatively analyzed with antibodies to proteins involved in the apoptotic pathway. As expected, Bcl-2 levels were up to eight-fold higher in Bcl-2+ FL than in FH and Bcl-2- FL. However, there was no difference in levels of Mcl-1 and survivin among these three groups. Bcl-X(L) showed a trend for increased expression in Bcl-2- FL as compared with Bcl-2+ FL, although the differences did not reach statistical significance (P>0.1). The increase in Bcl-X(L) may provide an alternative antiapoptotic signal in FL negative for Bcl-2 protein. Interestingly, Bax expression was higher in FL (Bcl-2+ or -) than in FH (P=0.001). Notably, phospho-Akt (Ser-473) was increased in FL (Bcl-2+ or -) (P<0.03) with increased phospho-Bad (Ser-136), as compared with levels in FH. The activation of the Akt/Bad pathway provides further evidence of prosurvival signals in FL, independent of Bcl-2 alone. These data suggest that nodal FL represents a single disease with a final common biochemical pathway.
已知Bcl-2蛋白的过表达在滤泡性淋巴瘤（FL）的发病机制中起作用。然而，10%-15%的FL通过免疫组织化学检测Bcl-2呈阴性，这增加了另一种基因产物可能提供促生存信号的可能性。我们使用反相蛋白质微阵列分析通过激光捕获显微切割从以下样本中分离的滤泡中心细胞的裂解物：Bcl-2阳性FL、Bcl-2阴性FL和反应性滤泡增生（FH）（每组9例）。TUNEL分析证实Bcl-2阳性FL和Bcl-2阴性FL中的凋亡水平相似且降低，表明存在不依赖Bcl-2的凋亡抑制可能性。用针对凋亡途径相关蛋白质的抗体对微阵列进行定量分析。正如预期的那样，Bcl-2阳性FL中的Bcl-2水平比FH和Bcl-2阴性FL中的高多达八倍。然而，这三组中Mcl-1和survivin的水平没有差异。与Bcl-2阳性FL相比，Bcl-X(L)在Bcl-2阴性FL中呈现表达增加的趋势，尽管差异未达到统计学意义（P>0.1）。Bcl-X(L)的增加可能在Bcl-2蛋白阴性的FL中提供替代的抗凋亡信号。有趣的是，FL（Bcl-2阳性或阴性）中的Bax表达高于FH（P=0.001）。值得注意的是，与FH中的水平相比，FL（Bcl-2阳性或阴性）中磷酸化Akt（Ser-473）增加（P<0.03），同时磷酸化Bad（Ser-136）增加。Akt/Bad途径的激活为FL中不依赖单独Bcl-2的促生存信号提供了进一步证据。这些数据表明淋巴结FL代表一种具有最终共同生化途径的单一疾病。
