Association between the 308 G>A variant of the TNF-α gene and risk of colorectal cancer

Assessment of the Tumor-Stroma Ratio and Tumor-Infiltrating Lymphocytes in Colorectal Cancer: Inter-Observer Agreement Evaluation

BACKGROUND

To implement the new marker in clinical practice, reliability assessment, validation, and standardization of utilization must be applied. This study evaluated the reliability of tumor-infiltrating lymphocytes (TILs) and tumor-stroma ratio (TSR) assessment through conventional microscopy by comparing observers' estimations.

METHODS

Intratumoral and tumor-front stromal TILs, and TSR, were assessed by three pathologists using 86 CRC HE slides. TSR and TILs were categorized using one and four different proposed cutoff systems, respectively, and agreement was assessed using the intraclass coefficient (ICC) and Cohen's kappa statistics. Pairwise evaluation of agreement was performed using the Fleiss kappa statistic and the concordance rate and it was visualized by Bland-Altman plots. To investigate the association between biomarkers and patient data, Pearson's correlation analysis was applied.

RESULTS

For the evaluation of intratumoral stromal TILs, ICC of 0.505 (95% CI: 0.35-0.64) was obtained, kappa values were in the range of 0.21 to 0.38, and concordance rates in the range of 0.61 to 0.72. For the evaluation of tumor-front TILs, ICC was 0.52 (95% CI: 0.32-0.67), the overall kappa value ranged from 0.24 to 0.30, and the concordance rate ranged from 0.66 to 0.72. For estimating the TSR, the ICC was 0.48 (95% CI: 0.35-0.60), the kappa value was 0.49 and the concordance rate was 0.76. We observed a significant correlation between tumor grade and the median of TSR (0.29 (95% CI: 0.032-0.51), p-value = 0.03).

CONCLUSIONS

The agreement between pathologists in estimating these markers corresponds to poor-to-moderate agreement; implementing immune scores in daily practice requires more concentration in inter-observer agreements.

Understanding the potential immunogenetic role of TNFα-308 polymorphism in the pathogenesis of recurrent miscarriage

Background

Recurrent miscarriage (RM) represents the spontaneous termination of two or more successive pregnancies. TNFα is a proinflammatory cytokine that is often considered harmful for embryonic development when expressed beyond normal levels.

Aim

The study was conducted to assess the association between TNFα-308 polymorphism and RM pathogenesis.

Methods

Samples of blood were obtained from patients and controls through venipuncture. The levels of TNFα in serum were measured by ELISA. TNFα gene promoter-associated single-nucleotide polymorphism was investigated with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques with precise primers and the restriction endonuclease, NcoI.

Results

Serum TNFα levels in patients were considerably high (p < 0.05) than controls. The genotype and allele frequencies for TNFα gene polymorphism differs significantly (p = 0.0089; p = 0.0043 respectively) between patients and controls. The TNFα-308 SNP exhibited a link with higher RM risk in heterozygous (GG vs. GA; OR: 3.086, 95% CI: 1.475-6.480; p: 0.0027), dominant (GG vs. GA + AA; OR: 2.919, 95% CI: 1.410-6.056, p: 0.0038), and allelic/codominant (G vs. A; OR: 2.449, 95% CI: 1.313-4.644, p: 0.0064) models. However, this SNP showed an insignificant association with higher and lower RM risk in homozygous (GG vs. AA; OR: 1.915, 95% CI: 0.3804-10.99, p: 0.6560) and recessive (AA vs. GA + GG; OR: 0.6596, 95% CI: 0.1152-3.297, p: >0.9999) models, respectively. Further, the TNFα-308G/A genotype frequencies were in concord with HWE both in the controls (χ² = 3.235; p = 0.1985) and the patients (χ² = 0.0117; p = 0.9942).

Conclusion

The serum TNFα levels were significantly higher in the patients than the controls. The genotyping analysis also demonstrated that TNFα-308G/A SNP significantly increases the overall risk of RM, suggesting that the SNP modulates the TNFα gene expression and thereby increases serum TNFα levels that adversely affect the pregnancy outcome.