Impact of interleukin-32 germ-line rs28372698 and intronic rs12934561 polymorphisms on cancer development: A systematic review and meta-analysis

The relationship between 1,25(OH)2D3 levels and interleukin-32 and vascular endothelial growth factor levels in endometriosis cyst tissue: An original article

Background

Endometriosis involves the presence of endometrial-like tissue outside the uterus, driven by inflammatory pathways including elevated interleukin-32 and vascular endothelial growth factor. One potential anti-inflammatory agent is active vitamin D (1,25(OH)2D3).

Objectives

This research investigates the correlation among 1,25(OH)2D3 levels, interleukin-32, and vascular endothelial growth factor in confirmed endometriosis cases.

Methods

This observational analytic correlational study aimed to explore the relationship between these inflammatory factors and vitamin D levels in endometriosis. The study involved 46 participants, with histopathologically confirmed endometriosis cyst tissue collected from patients undergoing laparotomy or laparoscopy at three hospitals: Dr. Hasan Sadikin Hospital Bandung, Cibabat General Hospital Cimahi, and Limijati Maternity and Children's Hospital. The levels of interleukin-32, vascular endothelial growth factor, and 1,25(OH)2D3 were measured using the enzyme-linked immunosorbent assay method at the Clinical Pathology Laboratory of Dr. Hasan Sadikin Hospital Bandung.

Results

The study revealed significant negative correlations between 1,25(OH)2D3 and both interleukin-32 (r = -0.346; p = 0.019) and vascular endothelial growth factor levels (r = -0.316; p = 0.032). Conversely, there was a significant positive correlation between vascular endothelial growth factor and interleukin-32 (r = 0.490; p = 0.001).

Conclusions

These findings underscore the role of active vitamin D in mitigating inflammation associated with endometriosis by reducing interleukin-32 and vascular endothelial growth factor, critical factors in inflammatory responses and blood vessel formation. Moreover, the positive association between vascular endothelial growth factor and interleukin-32 highlights their collaborative role in the inflammatory processes underlying endometriosis. This study contributes to understanding how vitamin D may modulate key inflammatory pathways implicated in the pathogenesis of this condition.

Genetic Association between Polymorphisms of Interleukin-32 and Dilated Cardiomyopathy in Chinese Han Population

Background

Dilated cardiomyopathy is a primary myocardial disease and one of the critical causes of heart failure. It is the most common indication for heart transplantation worldwide, and most idiopathic dilated cardiomyopathies are sporadic and multifactorial. Evidence has supported that several inflammatory cytokines and immune responses are involved in its pathological process. Interleukin-32 is a proinflammatory cytokine and is elevated during the worsening cardiac function. Herein, we evaluated the correlation between interleukin-32 gene polymorphisms (rs12934561 and rs28372698) and the susceptibility to dilated cardiomyopathy.

Methods

We enrolled 418 dilated cardiomyopathy patients and 437 healthy controls. The polymerase chain reaction-restriction fragment length polymorphism method was used for genotyping the two single-nucleotide polymorphisms (SNPs), and SPSS software was used for statistical analyses.

Results

The C allele and CC genotype frequencies of rs12934561 were remarkably elevated in dilated cardiomyopathy patients compared to controls (both P < 0.001). The A allele and AA genotype frequencies of rs28372698 significantly decreased in dilated cardiomyopathy patients (P = 0.004 and P = 0.02, respectively). Compared to TT/TC genotype carriers of rs12934561, CC homozygotes presented an increased risk of dilated cardiomyopathy when the left ventricular ejection fraction no more than 30% (P = 0.02).

Conclusions

The IL-32 gene polymorphisms might implicate in DCM risk in the Chinese Han population, and rs12934561 could be a potential forecasting factor for screening high-risk population for DCM.

A Paradoxical Effect of Interleukin-32 Isoforms on Cancer

IL-32 plays a contradictory role such as tumor proliferation or suppressor in cancer development depending on the cancer type. In most cancers, it was found that the high expression of IL-32 was associated with more proliferative and progression of cancer. However, studying the isoforms of IL-32 cytokine has placed its paradoxical role into a wide range of functions based on its dominant isoform and surrounding environment. IL-32β, for example, was found mostly in different types of cancer and associated with cancer expansion. This observation is legitimate since cancer exhibits some hypoxic environment and IL-32β was known to be induced under hypoxic conditions. However, IL-32θ interacts directly with protein kinase C-δ reducing NF-κB and STAT3 levels to inhibit epithelial-mesenchymal transition (EMT). This effect could explain the different functions of IL-32 isoforms in cancer. However, pro- or antitumor activity which is dependant on obesity, gender, and age as it relates to IL-32 has yet to be studied. Obesity-related IL-32 regulation indicated the role of IL-32 in cancer metabolism and inflammation. IL-32-specific direction in cancer therapy is difficult to conclude. In this review, we address that the paradoxical effect of IL-32 on cancer is attributed to the dominant isoform, cancer type, tumor microenvironment, and genetic background. IL-32 seems to have a contradictory role in cancer. However, investigating multiple IL-32 isoforms could explain this doubt and bring us closer to using them in therapy.