Engrailed‑2 promoter hyper‑methylation is associated with its downregulation in clear cell renal cell carcinoma

Abstract

Abstract. In a previous study by the present authors, it was identified that the expression of engrailed-2 (EN2) gene was downregulated in clear cell renal cell carcinoma (cc-RCC). The aim of the present study was to determine whether aberrant methylation was the mechanism underlying the silencing of EN2 gene in cc-RCC. A total of forty paired cc-RCC tissues, four cc-RCC cell lines and one normal human proximal tubule epithelial cell line were evaluated for EN2 gene methylation status using methylation-specific polymerase chain reaction (PCR). Following treatment with 5-Aza-dc, reverse transcription-quantitative PCR and western blot analysis were performed to examine the expression of EN2. Furthermore, cell proliferation, apoptosis and invasion assays were conducted to analyze the inhibitory effects of EN2 re-expression in 786-O cells. The results of the present study demonstrated that hyper-methylation of EN2 was identified in 12/40 cc-RCC tissues and all cc-RCC cell lines. The methylation status of the EN2 gene was revealed to be associated with histological grade and tumor size in cc-RCC. Following 5-Aza-dc treatment, demethylation of the EN2 gene was identified in 786-O cells, in conjunction with EN2 re-expression. Furthermore, re-activation of the EN2 gene markedly inhibited the proliferative and invasive capacities of cc-RCC. The results of the present study demonstrated that the EN2 gene promoter was hyper-methylated in cc-RCC, which may underlie the silencing of the EN2 gene in cc-RCC.

Genome-Wide DNA Methylation in Peripheral Blood and Long-Term Exposure to Source-Specific Transportation Noise and Air Pollution: The SAPALDIA Study

“…EN2 functions in the development of the central nervous system and is commonly associated with autism (Lupu et al 2018;Márquez-Valadez et al 2018). Aberrant methylation in EN2 was recently linked to clear cell renal carcinoma (Lai et al 2017). Although these highlight certain distinct and shared pattern of associations, they demonstrate the complex network in the mechanisms linking these exposures to disease.…”

Engrailed 2 (EN2) acts as a glioma suppressor by inhibiting tumor proliferation/invasion and enhancing sensitivity to temozolomide

“…EN2 is a member of the homeobox family, which encodes a homeodomain-containing transcription factor that is essential for early development. Elevation of EN2 has been highly correlated with the proliferation, invasion, and migration in several types of malignancies [18][19][20][21][22][23][24][25][26], however, controversial results show that EN2 is silenced in other cancers [27][28][29], and thus EN2 acts as a potential diagnostic and prognostic biomarker [23,[30][31][32][33]. However, decreased EN2 in renal carcinoma has been observed and downregulation of EN2 in 786-O cell line promoted proliferation and reduced apoptosis [27,34,35].…”

“…Engrailed-2 (EN2) gene encodes a homeobox-containing transcription factor and participates in the regionalization, patterning and cell differentiation in early brain development [15][16][17]. Accumulated evidence demonstrates that EN2 is highly associated with tumorigenesis in some types of cancers [18][19][20][21][22][23][24][25][26], however, controversial results show that EN2 is silenced in other cancers [27,28]. As for glioma, it remains unclear about EN2 expression pattern and potential functions.…”

A novel biflavone from Reineckia carnea induces apoptosis of human renal cancer 786-O cells

“…According to statistics, there will be an estimated 431,288 new cases of renal cell carcinoma and 179,368 deaths worldwide in 2020 (Sung et al, 2021). So far, the specific mechanism of the occurrence and development of kidney cancer is still unclear, and the discovery of new biological markers is of great significance to the early diagnosis and prognosis of kidney cancer (Lai et al, 2017;Xue et al, 2019). Since kidney cancer is insensitive to radiotherapy, surgical resection remains the main treatment for kidney cancer, but surgical resection is only applicable to a small number of patients with early-stage tumors, while there is a high risk of recurrence and metastasis after surgery (Schrader et al, 2006;Li et al, 2018).…”