SIRT1 gene polymorphisms and its protein level in colorectal cancer

Association of lncRNA MEG3 rs941576 polymorphism, expression profile, and its related targets with the risk of obesity-related colorectal cancer: potential clinical insights

The identification of novel screening tools is imperative to empower the early detection of colorectal cancer (CRC). The influence of the long non-coding RNA maternally expressed gene 3 (MEG3) rs941576 single nucleotide polymorphism on CRC susceptibility remains uninvestigated. This research appraised MEG3 rs941576 association with the risk and clinical features of CRC and obesity-related CRC and its impact on serum MEG3 expression and its targets miR-27a/insulin-like growth factor 1 (IGF1)/IGF binding protein 3 (IGFBP3) and miR-181a/sirtuin 1 (SIRT1), along with the potential of these markers in obesity-related CRC diagnosis. 130 CRC patients (60 non-obese and 70 obese) and 120 cancer-free controls (64 non-obese and 56 obese) were enrolled. MEG3 targets were selected using bioinformatics analysis. MEG3 rs941576 was associated with magnified CRC risk in overall (OR (95% CI) 4.69(1.51-14.57), P = 0.0018) and stratified age and gender groups, but not with obesity-related CRC risk or MEG3/downstream targets' expression. Escalated miR-27a and IGFBP3 and reduced IGF1 serum levels were concomitant with MEG3 downregulation in overall CRC patients versus controls and obese versus non-obese CRC patients. Serum miR-181a and SIRT1 were upregulated in CRC patients versus controls but weren't altered in the obese versus non-obese comparison. Serum miR-181a and miR-27a were superior in overall and obesity-related CRC diagnosis, respectively; meanwhile, IGF1 was superior in distinguishing obese from non-obese CRC patients. Only serum miR-27a was associated with obesity-related CRC risk in multivariate logistic analysis. Among overall CRC patients, MEG3 rs941576 was associated with lymph node (LN) metastasis and tumor stage, serum MEG3 was negatively correlated with tumor stage, while SIRT1 was correlated with the anatomical site. Significant correlations were recorded between MEG3 and anatomical site, SIRT1 and tumor stage, and miR-27a/IGFBP3 and LN metastasis among obese CRC patients, while IGF1 was correlated with tumor stage and LN metastasis among non-obese CRC patients. Conclusively, this study advocates MEG3 rs941576 as a novel genetic marker of CRC susceptibility and prognosis. Our findings accentuate circulating MEG3/miR-27a/IGF1/IGFBP3, especially miR-27a as valuable markers for the early detection of obesity-related CRC. This axis along with SIRT1 could benefit obesity-related CRC prognosis.

Association of SIRT1 single gene nucleotide polymorphisms and serum SIRT1 levels with laryngeal squamous cell carcinoma patient survival rate

BACKGROUND

SIRT1 is a multifunctional protein, possibly essential in tumorigenesis pathways, which can act both as a tumor promoter and tumor suppressor depending on the oncogenes, specific to particular tumors. Pathogenesis of laryngeal cancer is multifactorial and the association of SIRT1 expression with the clinical characteristics and prognosis of LSCC has not been fully identified.

OBJECTIVES

The study aimed to evaluate associations between single gene nucleotide polymorphisms (SNPs) of SIRT1 (rs3818292, rs3758391, and rs7895833), serum SIRT1 levels, and 5-year survival rate in patients with laryngeal squamous cell carcinoma (LSCC).

METHODS

The study involved 302 patients with LSCC and 409 healthy control subjects. The genotyping of SNPs was performed using RT-PCR, and serum SIRT1 levels were determined by the ELISA method.

RESULTS

Our study found significant differences in genotype distributions of SIRT1 rs3758391 polymorphisms between the study groups. SIRT1 rs3758391 T/T genotype was associated with the increased LSCC development odds (OR = 1.960 95% CI = 1.028-3.737; p= 0.041). Carriers of SIRT1 rs3758391 T/T genotype had statistically significantly increased odds of LSCC development into advanced stages under the codominant and recessive genetic models (OR = 2.387 95% CI = 1.091-5.222; p= 0.029 and OR = 2.287 95% CI = 1.070-4.888; p= 0.033, respectively). There were no statistically significant differences in serum SIRT1 levels between the LSCC and control groups. However, LSCC patients with SIRT1 rs3818292 AG genotype demonstrated a tendency to significantly lower SIRT1 serum levels than controls (p= 0.034). No statistically significant associations between SIRT1 (rs3818292, rs3758391, and rs7895833) SNPs and the 5-year survival rate of LSCC patients were found.

CONCLUSION

The present study indicated a statistically significant association between the SIRT1 rs3758391 T/T genotype and increased LSCC development odds. LSCC patients with SIRT1 rs3818292 AG genotype showed a tendency to manifest with lower SIRT1 serum levels. No associations between SIRT1 SNPs and the 5-year survival rate of LSCC patients were detected.

SIRT1 Contributes as an Invasiveness Marker in Pituitary Adenoma

The aim of the study was to find the association between SIRT1 concentration, SIRT1 rs3758391, rs3818292, rs7895833 polymorphisms and clinical manifestations of pituitary adenoma (PA). The study included 108 patients with PA and 216 healthy individuals. Using commercial kits, DNA was extracted from peripheral blood leukocytes. To determine the PA and control group subjects genotypes was used real-time PCR method, for SIRT concentration measurement we used ELISA method. The statistical data analysis was completed using the “BM SPSS Statistics 20.0” software. Results: We performed statistical analysis of SNPs in the patient and healthy controls and patients’ subgroups and found statistically significant differences in rs7895833 genotype (A/A, A/G, G/G) distributions between the active PA and control groups (67.9%, 24.6%, 5.7% vs. 72.2%, 27.3%, 0.5%; p = 0.02) Also, the results showed that the rs7895833 G/G genotype is associated with about 13-fold increased odds of active PA development compared to the A/A (OR = 13.95% CI: 1.314–128.632; p = 0.028) and both A/A and A/G genotypes (OR = 12.9; 95% CI: 1.314–126.624; p = 0.028). There is ample evidence that SIRT1 in the pituitary and other target organs modifies the synthesis, secretion, and activity of hormones to trigger adaptive responses, thus we decided to include this in our study. When determining the serum concentration of SIRT1, we did not find a statistically significant difference between the PA group and the control group. SIRT1 serum level was statistically significantly higher in women with PA than in healthy control women (1.115 (3.748) vs. 136 (0.211); p = 0.008). To conclude—SIRT1 rs7895833 G/G genotype is associated with about 13-fold increased odds of active PA development compared to the A/A and both A/A and A/G genotypes. SIRT1 serum levels are higher in women with PA than in healthy women.