Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Av. Lázaro Cárdenas s/n, Chilpancingo 39090, Mexico.
Departamento de Parasitología, Instituto de Diagnóstico y Referencia Epidemiológicos "Dr. Manuel Martínez Báez", Francisco de P. Miranda 177, Mexico City 01480, Mexico.
Medicina (Kaunas). 2023 Mar 9;59(3):537. doi: 10.3390/medicina59030537.
REST (RE1-silencing transcription factor) diminution is associated with transcriptional relaxation, neuropeptide overexpression, and phenotype redefinition in neuroendocrine cancers, but this effect has barely been studied in cervical cancer (CC). We previously reported reduced expressions of REST in samples with premalignant lesions and CC; however, the transcriptional consequences for neural genes associated with reduced REST expression in CC are unknown. Therefore, the objective of this work was to evaluate the expression of neuronal genes in cancerous cells with reduced expression levels of REST. : Here, we monitored levels of REST by immunostaining along the premalignant lesions and in invasive cervical squamous cell carcinoma (SCC) and endocervical adenocarcinoma (ADC) in tissue samples from female patients from southern Mexico and the derivative cell lines SiHa and HeLa, respectively. Next, we selected REST target genes in silico and explored the effect of REST silencing by RT-PCR in siRNA-treated HeLa cells. : The results show a REST diminution in premalignant lesions, SCC, ADC, and cancerous cell lines. Further REST silencing in HeLa cells altered the expression of genes containing the RE1 (Restrictive Element 1) sequence, including CgA (chromogranin A), CHRNβ2 (cholinergic receptor nicotinic β 2 subunit), BDNF (brain-derived neurotrophic factor), CRF (corticotropin-releasing factor), and RASSF1A (Ras association domain family 1). : This work provides preliminary evidence of the role of REST loss in the transcriptional regulation of its target genes in HeLa cells, which could have positive implications for the search for new biomarkers of cervical cancer.
REST（RE1 沉默转录因子）减少与神经内分泌癌中转录松弛、神经肽过表达和表型重新定义有关，但这种效应在宫颈癌（CC）中几乎没有研究过。我们之前报道了在癌前病变和 CC 样本中 REST 表达减少；然而，与 REST 表达减少相关的神经基因在 CC 中的转录后果尚不清楚。因此，这项工作的目的是评估在 REST 表达水平降低的癌细胞中神经基因的表达。
在这里，我们通过免疫染色监测了女性墨西哥南部患者组织样本中的癌前病变和浸润性宫颈鳞状细胞癌（SCC）和宫颈内膜腺癌（ADC）中 REST 的水平，以及相应的细胞系 SiHa 和 HeLa。接下来，我们通过 RT-PCR 在 siRNA 处理的 HeLa 细胞中探讨了 REST 沉默的效果，对 REST 靶基因进行了计算机预测。
结果显示，癌前病变、SCC、ADC 和癌细胞系中 REST 减少。进一步沉默 HeLa 细胞中的 REST 改变了含有 RE1（Restrictive Element 1）序列的基因的表达，包括 CgA（嗜铬粒蛋白 A）、CHRNβ2（胆碱能受体烟碱β2 亚基）、BDNF（脑源性神经营养因子）、CRF（促皮质素释放因子）和 RASSF1A（Ras 相关结构域家族 1）。
这项工作初步证明了 REST 缺失在 HeLa 细胞中其靶基因转录调控中的作用，这可能对寻找宫颈癌新的生物标志物具有积极意义。
