Swellam Menha, Saad Entsar A, Sabry Shimaa, Denewer Adel, Abdel Malak Camelia, Abouzid Amr
Biochemistry Department, Genetic Engineering and Biotechnology Research Division, High Throughput Molecular and Genetic Laboratory, Center for Excellences for Advanced Sciences, National Research Centre, Dokki, Giza, Egypt.
Chemistry Department, Faculty of Science, Damietta University, Damietta, 34517, Egypt.
J Genet Eng Biotechnol. 2021 Apr 6;19(1):54. doi: 10.1186/s43141-021-00154-x.
Diagnosis of breast cancer is more complicated due to lack of minimal invasive biomarker with sufficient precision. DNA methylation is a promising marker for cancer diagnosis. In this study, authors evaluated methylation patterns for PTEN and SMAD4 in blood samples using EpiTect Methyl II QPCR assay quantitative PCR technology.
Methylation status for PTEN and SMAD4 were statistically significant as breast cancer patients reported hypermethylation compared to benign and control groups (77.1 ± 17.9 vs. 24.9 ± 4.5 and 15.1 ± 1.4 and 70.1 ± 14.4 vs. 28.2 ± 0.61 and 29.5 ± 3.6, respectively). ROC curve analysis revealed that both PTEN (AUC = 0.992) and SMAD4 (AUC = 0.853) had good discriminative power for differentiating BC from all non-cancer individuals (benign and healthy combined) compared to routine tumor markers CEA (AUC = 0.538) and CA15.3 (AUC = 0.686). High PTEN methylation degree was associated with late stages (84.2 ± 17.4), positive lymph node (84.2 ± 18.5), positive ER (81.3 ± 19.7), positive PgR (79.5 ± 19.1), and positive HER2 (80.7 ± 19.0) vs. 67.4 ± 13.8, 70.6 ± 14.8, 72.8 ± 14.9, 72.5 ± 14.7, and 70.2 ± 13.5 in early stages, negative lymph node, negative ER, negative PgR, and negative HER2, respectively. Similar results were obtained regarding SMAD4 methylation. Sensitivity, specificity, positive and negative predictive values, and accuracy for methylated PTEN were 100%, 95%, 99.1%, 100%, and 95%, respectively when differentiated BC from all-non cancer controls. Interestingly, PTEN could distinguish early BC stages with good sensitivity 84.4%, 51.4%, 69.1%, 72%, and 70%, respectively.
Methylation status of PTEN and SMAD4 is a promising blood marker for early detection of breast cancer. Future studies are needed for their role as prognostic markers.
由于缺乏具有足够精度的微创生物标志物，乳腺癌的诊断更为复杂。DNA甲基化是一种很有前景的癌症诊断标志物。在本研究中，作者使用EpiTect Methyl II QPCR定量PCR技术评估了血液样本中PTEN和SMAD4的甲基化模式。
与良性组和对照组相比，乳腺癌患者PTEN和SMAD4的甲基化状态具有统计学意义，表现为高甲基化（分别为77.1±17.9 vs. 24.9±4.5和15.1±1.4以及70.1±14.4 vs. 28.2±0.61和29.5±3.6）。ROC曲线分析显示，与常规肿瘤标志物癌胚抗原（CEA，AUC = 0.538）和糖类抗原15.3（CA15.3，AUC = 0.686）相比，PTEN（AUC = 0.992）和SMAD4（AUC = 0.853）在区分乳腺癌与所有非癌症个体（良性和健康个体合并）方面具有良好的鉴别能力。PTEN高甲基化程度与晚期（84.2±17.4）、淋巴结阳性（84.2±18.5）、雌激素受体阳性（ER，81.3±19.7）、孕激素受体阳性（PgR，79.5±19.1）和人表皮生长因子受体2阳性（HER2，80.7±19.0）相关，而早期、淋巴结阴性、ER阴性、PgR阴性和HER2阴性时分别为67.4±13.8、70.6±14.8、72.8±14.9、72.5±14.7和70.2±13.5。关于SMAD4甲基化也获得了类似结果。当区分乳腺癌与所有非癌症对照时，甲基化PTEN的敏感性、特异性、阳性和阴性预测值以及准确性分别为100%、95%、99.1%、100%和95%。有趣的是，PTEN能够以良好的敏感性区分早期乳腺癌阶段，敏感性分别为84.4%、51.4%、69.1%、72%和70%。
PTEN和SMAD4的甲基化状态是早期检测乳腺癌的一种很有前景的血液标志物。它们作为预后标志物的作用还需要未来的研究。
