Fendri Ali, Kontos Christos K, Khabir Abdelmajid, Mokdad-Gargouri Raja, Ardavanis Alexandros, Scorilas Andreas
Unité de Recherche Génétique du Cancer et Production de protéines thérapeutiques, Centre de Biotechnologie de Sfax, Sfax, Tunisia.
Tumour Biol. 2010 Oct;31(5):391-9. doi: 10.1007/s13277-010-0047-3. Epub 2010 Jun 1.
Programmed cell death plays a vital role in a wide variety of physiological processes. Defects in apoptotic cell death contribute to neoplastic diseases by preventing or delaying normal cell death. BCL2 (Bcl-2) is an anti-apoptotic gene with marked up-regulation in various malignancies, such as breast cancer, in which expression of the BCL2 protein has been proposed as a prognostic tumor biomarker. The purpose of the current study was to investigate mRNA expression of the BCL2 gene in nasopharyngeal carcinoma (NPC) biopsies and assess its prognostic value. For this purpose, total RNA was isolated from 89 malignant and hyperplastic nasopharyngeal biopsies from Tunisian patients. After testing the quality of the extracted RNA, cDNA was prepared by reverse transcription. A highly sensitive real-time PCR methodology for BCL2 mRNA quantification was developed using SYBR® Green chemistry. GAPDH served as an endogenous control gene. Relative quantification analysis was performed using the comparative C (T) (2(-∆∆CT)) method. High BCL2 mRNA levels were detected in advanced-stage nasopharyngeal tumors (p = 0.030). Furthermore, BCL2 mRNA expression was strongly associated with lymph node involvement (p = 0.009) and presence of distal metastases (p = 0.013). Survival analysis demonstrated that patients with BCL2-positive nasopharyngeal tumors have significantly shorter disease-free and overall survival (p = 0.011 and p = 0.028, respectively). The major contribution of the current study is the quantification and evaluation, for the first time, of the prognostic significance of the BCL2 mRNA expression in nasopharyngeal carcinoma (NPC) patients. Our results suggest that mRNA expression levels of BCL2 may represent a novel unfavorable and independent tumor biomarker for nasopharyngeal carcinoma.
程序性细胞死亡在多种生理过程中起着至关重要的作用。凋亡性细胞死亡的缺陷通过阻止或延迟正常细胞死亡而导致肿瘤性疾病。BCL2（Bcl-2）是一种抗凋亡基因，在各种恶性肿瘤（如乳腺癌）中显著上调，其中BCL2蛋白的表达已被提议作为一种预后肿瘤生物标志物。本研究的目的是调查鼻咽癌（NPC）活检组织中BCL2基因的mRNA表达，并评估其预后价值。为此，从突尼斯患者的89份恶性和增生性鼻咽活检组织中分离出总RNA。在检测提取的RNA质量后，通过逆转录制备cDNA。使用SYBR® Green化学方法开发了一种用于BCL2 mRNA定量的高度灵敏的实时PCR方法。GAPDH作为内参基因。使用比较C（T）（2（-∆∆CT））方法进行相对定量分析。在晚期鼻咽癌肿瘤中检测到高BCL2 mRNA水平（p = 0.030）。此外，BCL2 mRNA表达与淋巴结受累（p = 0.009）和远处转移的存在（p = 0.013）密切相关。生存分析表明，BCL2阳性鼻咽癌患者的无病生存期和总生存期显著缩短（分别为p = 0.011和p = 0.028）。本研究的主要贡献是首次对鼻咽癌（NPC）患者中BCL2 mRNA表达的预后意义进行了定量和评估。我们的结果表明，BCL2的mRNA表达水平可能代表一种新的不良且独立的鼻咽癌肿瘤生物标志物。
