PURPOSE: The DNA methylation mediated by specific DNA methyltransferases (DNMTs), results in the epigenetic silencing of multiple genes which are implicated in human breast cancer. We hypothesized that the natural compounds modulate the expression of DNMTs and their associated proteins in the breast cancer cell lines and affect the methylation mediated gene silencing. METHODS: The DNMTs transcript expression was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) in the tumors and the adjacent normal breast tissues of the patients with invasive ductal breast carcinoma. We tested the hypothesis that the natural compounds, viz., epigallocatechin gallate (EGCG), genistein, withaferin A, curcumin, resveratrol, and guggulsterone, have demethylation potential. To investigate this hypothesis, we analyzed the DNMTs expression at the transcript levels, followed by the analysis of DNMT1 and its associated proteins (HDAC1, MeCP2, and MBD2). RESULTS: The increased DNMTs transcripts expression, viz., DNMT1, DNMT3a, and DNMT3b, in the breast cancer tissues suggest involvement of the DNMTs in the breast carcinogenesis. Quantitative RT-PCR analysis revealed that the treatment with natural compounds, viz., EGCG, genistein, withaferin A, curcumin, resveratrol, and guggulsterone, resulted in a significant decrease in the transcript levels of all the DNMTs investigated. Importantly, these natural compounds decreased the protein levels of DNMT1, HDAC1, and MeCP2. CONCLUSION: Our results demonstrate that the natural compounds, EGCG, genistein, withaferin A, curcumin, resveratrol, and guggulsterone, have the potential to reverse the epigenetic changes. Moreover, their lack of toxicity makes these natural compounds promising candidates for the chemoprevention of the breast cancer. In-depth future mechanistic studies aimed to elucidate how these compounds affect the gene transcription are warranted.
Breast ; Breast Neoplasms ; Catechin ; Cell Line ; Chemoprevention ; Curcumin ; DNA ; DNA Methylation ; Epigenomics ; Genistein ; Humans ; Methylation ; Methyltransferases ; Pregnenediones ; Proteins ; Stilbenes ; Withanolides

OBJECTIVES: To comparatively evaluate the efficacy of photo-activated disinfection (PAD), calcium hydroxide (CH) and their combination on the treatment outcome of indirect pulp treatment (IPT). MATERIALS AND METHODS: Institutional ethical clearance and informed consent of the patients were taken. The study was also registered with clinical registry of India. Sixty permanent molars exhibiting deep occlusal carious lesion in patients with the age range of 18 - 22 yr were included. Clinical and radiographic evaluation and set inclusion and exclusion criteria's were followed. Gross caries excavation was accomplished. In group I (n = 20) PAD was applied for sixty seconds. In group II (n = 20), CH was applied to the remaining carious dentin, while in group III (n = 20), PAD application was followed by CH placement. The teeth were permanently restored. They were clinically and radiographically followed-up at 45 day, 6 mon and 12 mon. Relative density of the remaining affected dentin was measured by 'Radiovisiography (RVG) densitometric' analysis. RESULTS: Successful outcome with an increase in radiographic grey values were observed in all three groups. However, on inter-group comparison, this change was not significant (p > 0.05). CONCLUSIONS: PAD and CH both have equal disinfection efficacy in the treatment of deep carious dentin. PAD alone is as effective for treatment of deep carious lesion as calcium hydroxide and hence can be used as an alternative to CH. They can be used independently in IPT, since combining both does not offer any additional therapeutic benefits.
Calcium Hydroxide* ; Dental Caries* ; Dentin ; Disinfection* ; Humans ; India ; Informed Consent ; Molar ; Specific Gravity ; Tooth ; Treatment Outcome