Marques Marcia M, Evangelista Adriane F, Macedo Taciane, Vieira René Aloisio da Costa, Scapulatempo-Neto Cristovam, Reis Rui M, Carvalho André L, Silva Ismael Dale Cotrim Guerreiro da
Centro de Pesquisa em Oncologia Molecular (CPOM), Hospital de Cancer de Barretos, Barretos, SP, BR.
Faculdade de Ciencias da Saude de Barretos Dr Paulo Prata (FACISB), Barretos, SP, BR.
Clinics (Sao Paulo). 2018 Jul 10;73:e184. doi: 10.6061/clinics/2018/e184.
MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at the posttranscriptional level. Some miRNAs, including let-7a and miR-195, have been described as tumor suppressors. However, the roles of these microRNAs in breast cancer progression remain controversial. The aim of this study is to evaluate miR-195 and let-7a expression as potential biomarkers of invasive breast cancer.
In the present study, 200 individuals were separated into three groups: (i) 72 women constituting the control group who were selected according to rigorous and well-established criteria; (ii) 56 patients with benign breast tumors; and (iii) 72 patients with malignant breast cancers of different clinical stages. The miR-195 and let-7a expression levels in serum were evaluated by real-time PCR. The results were assessed alone and in combination, and the analysis included an estimation of sensitivity and specificity in ROC curves.
Compared with the benign and control groups, both microRNAs were downregulated in the malignant breast cancer patient group. Compared with the malignant group, the combination of both biomarkers in the control and benign groups showed good sensitivity and specificity in the serum with AUCs of 0.75 and 0.72, respectively. The biomarker combination for the control group versus the malignant group exhibited a better sensitivity and specificity than for the benign group versus the malignant group.
These findings support the evidence that the analysis of miR-195 and let-7a can be used as a non-invasive biomarker for breast cancer detection.
微小RNA（miRNA）是一类小的非编码RNA，可在转录后水平调节基因表达。一些miRNA，包括let-7a和miR-195，已被描述为肿瘤抑制因子。然而，这些微小RNA在乳腺癌进展中的作用仍存在争议。本研究的目的是评估miR-195和let-7a的表达作为浸润性乳腺癌潜在生物标志物的可能性。
在本研究中，200名个体被分为三组：（i）72名女性组成的对照组，她们是根据严格且成熟的标准挑选出来的；（ii）56例患有乳腺良性肿瘤的患者；（iii）72例处于不同临床阶段的乳腺恶性肿瘤患者。通过实时PCR评估血清中miR-195和let-7a的表达水平。单独和联合评估结果，并在ROC曲线中分析敏感性和特异性。
与良性组和对照组相比，恶性乳腺癌患者组中这两种微小RNA均下调。与恶性组相比，对照组和良性组中这两种生物标志物的组合在血清中显示出良好的敏感性和特异性，AUC分别为0.75和0.72。对照组与恶性组的生物标志物组合比良性组与恶性组表现出更好的敏感性和特异性。
这些发现支持了miR-195和let-7a的分析可作为乳腺癌检测的非侵入性生物标志物的证据。
