RESUMO
Ovarian cancer has the most noteworthy lethal rate around gynecologic malignancies, and it is also considered as the fourth most frequent cancer in the woman in world. Two most critical barriers to treatment of ovarian malignancy are absence of early diagnostic markers and advancement of drug resistance after therapy, especially in advanced stages. Various epigenetic changes have been recognized in ovarian cancer. Recent progresses in our understanding of molecular pathogenesis of ovarian malignancy have dramatically provided potential new targets for molecularly targeted therapies. In very recent years, small interfering RNA (siRNA)-mediated gene silencing has been emerging as a novel treatment modality in preclinical studies in the light of its strong gene-specific silencing. Gene suppression mediated by RNA interference (RNAi) significantly suppressed gene expression at the messenger RNA (mRNA) and protein levels. SiRNAs have therapeutic potential for ovarian cancer through various mechanisms. In this review, we not only provide an overview of siRNA designing for epigenetic silencing of genes aberrantly expressed in ovarian cancer but also we will highlight that the epigenetically silenced genes offer new targets for therapeutic approaches based on re-expression of tumor suppressor genes via demethylating and deacetylating drugs.
Assuntos
Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , RNA Interferente Pequeno/genética , Montagem e Desmontagem da Cromatina , Metilação de DNA , Feminino , Histonas/metabolismo , Humanos , Terapia de Alvo Molecular , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/terapia , Interferência de RNARESUMO
BACKGROUND: Angiogenesis is an important biological process involved in the proliferation of endothelial cells, tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is considered as a prominent regulator of angiogenesis which exerts the aforementioned effect(s) through its respective receptors (VEGFR1 and VEGFR2). VEGF receptors are targeted as a therapeutic candidate for cancer growth inhibition. RNAi as a new and promising strategy has provided a useful means to specifically suppress gene expression in cancer cells. OBJECTIVES: The current study aimed to down-regulate expression of the VEGFR1 using siRNA. MATERIALS AND METHODS: This experimental study designed specific siRNAs against VEGFR1. Total RNA was extracted from human umbilical vain endothelial cell (HUVEC) and subsequently cDNA was synthetized. PCR was performed using specific primers to amplify the target gene. After double digestion and purification, the gene was cloned into pEFGP-N1 expression vector. Then, AGS cells were transfected with recombinant pEGFP-N1 using lipofectamin. The gene expression and down-regulation were evaluated by fluorescence scanning, reverse transcription PCR (RT-PCR) and Western blot techniques. RESULTS: Fluorescent scanning, RT-PCR (27.68%) and western blot analysis (31.06%) showed that the expression of VEGFR1 was suppressed effectively. CONCLUSIONS: The results of the current study showed that specifically designed siRNA can be considered as an appropriate strategy to suppress gene expression and might be a promising tool to prevent angiogenesis.
