Zeljko Mijuskovic

Melanoma risk is associated with vitamin D receptor gene polymorphisms.

Previous studies have reported that vitamin D receptor (VDR) gene polymorphisms are associated with the occurrence of various cancers, including melanoma. The aim of the current study was to investigate the association of VDR gene polymorphisms with melanoma risk, clinicopathological characteristics, and vitamin D levels. The study group included 117 patients (84 patients with superficial spreading melanoma and 33 patients with nodular melanoma). The control group included 122 sex-matched and age-matched healthy-blood donors of the same ethnicity. VDR gene polymorphisms FokI, EcoRV, TaqI, and ApaI were genotyped by real-time PCR. In 60 patients, the total 25-hydroxyvitamin D levels were evaluated in serum samples by direct chemiluminescence. Associations among parameters were considered to be significant if the P value was less than 0.05. Significant differences in the frequencies of VDR genotypes were observed between cases and the control group for FokI and TaqI polymorphisms (P<0.0001; P=0.005, respectively). Heterozygous Ff as well as mutant FF genotypes of the FokI polymorphism were associated with increased melanoma risk compared with the wild-type form [odds ratio (OR)=3.035, P=0.003; OR=9.276, P<0.0001, respectively]. A significantly increased melanoma risk was observed for the heterozygous Tt (OR=2.302, P=0.011) and the mutated variant tt (OR=3.697, P=0.003) of the TaqI polymorphism in comparison with the wild-type genotype. None of the polymorphisms studied was associated with clinicopathological characteristics and vitamin D serum level. Our results suggest that FokI and TaqI polymorphisms in the VDR gene may be considered as potential biomarkers for melanoma susceptibility. Low vitamin D levels in melanoma patients indicate the need for vitamin D supplementation.

A subpopulation that may correspond to granulocytic myeloid-derived suppressor cells reflects the clinical stage and progression of cutaneous melanoma

Seventy-eight melanoma patients and 10 healthy individuals were examined. Follow-up examinations of all melanoma patients were performed regularly every three months. Myeloid-derived suppressor cells (MDSC) were defined as lineage negative (CD3(-), CD19(-), CD56(-)), HLA-DR(-/low), CD11b(+) and CD33(+). Classification of granulocytic (GrMDSC) and monocytic (MoMDSC) subsets was based on the CD15 and CD14 expression, respectively. Unlike the MoMDSC, that were present in 60% of healthy controls and 15% of melanoma patients, the GrMDSC were present in all examined participants, and the melanoma patients were found to have statistically higher frequencies compared with healthy controls. Accordingly, we kept focused on GrMDSC frequencies in relation to the melanoma stages and course of the disease. The GrMDSC values are highest in stage IV melanoma patients, with statistical significance compared with stages IA, IB, IIA and IIB. Patients with progression had statistically higher GrMDSC counts comparing with those with stable disease (P = 0.0079). Patients who had progression-free interval (PFI) < 12 months showed significantly higher GrMDSC values compared with those with PFI > 12 months (P = 0.0333). GrMDSC showed significant negative correlation with PFI intervals (P = 0.0095). The GrMDSC subset was predominant in all our patients. We confirmed that GrMDSC do accumulate early in the peripheral blood of melanoma patients and their frequencies correlate narrowly with the clinical stage and the spread of the disease. The increase in GrMDSC frequencies correlates well with a progressive disease and could be considered a potential predictive biomarker of high-risk melanoma cases that are more likely to have a shorter PFI.

High Interleukin 27 Production is Associated with Early Clinical Stage and Localized Disease in Patients with Melanoma

Summary Background: The immune response in patients with melanoma is an important focus of research due to the tumor’s resistance and immunotherapy possibilities. IL-27 is one of the cytokines with antitumor properties. The role of IL-27 in the pathogenesis of melanoma is still unclear. The aim of this study was to examine the association between serum IL-27 levels and the clinical parameters of melanoma patients. Methods: The IL-27 concentration was determined by commercial ELISA in serum samples from melanoma patients (n=72) and healthy control subjects (n=44). Patients were classified according to AJCC clinical stage, TNM stage, the length of progression-free interval (PFI) and the extent of the disease (localized or widespread). Results: Average IL-27 values were increased in patients with early stages of melanoma compared to patients with terminal stages and control values. The highest IL-27 concentration was found in stage IIa. Patients in stages III and IV had significantly lower values of IL-27 compared to control. Patients with localized melanoma and shorter PFI had insignificantly increased IL-27 levels compared to patients with widespread disease and longer PFI. Patients with metastatic disease and stage TNM4 had significantly lower average IL-27 values compared to control. Patients with high production of IL-27 (>1000 pg/mL) were most numerous in IIa AJCC stage, with initial tumor size TNM2 and in the group of patients with localized disease. Conclusions: High levels of IL-27 in patients with melanoma are associated with the initial stages and localized disease.

Association Between Oxidative Stress and Melanoma Progression

Summary Background: Overproduction of free radicals accompanied with their insufficient removal/neutralization by antioxidative defense system impairs redox hemostasis in living organisms. Oxidative stress has been shown to be involved in all the stages of carcinogenesis and malignant melanocyte transformation. The aim of this study was to examine association between oxidative stress development and different stages of melanoma. Methods: The measured oxidative stress parameters included: superoxide anion radical, total and manganese superoxide dismutase, catalase and malondialdehyde. Oxidative stress parameters were measured spectrophotometrically in serum samples from melanoma patients (n=72) and healthy control subjects (n=30). Patients were classified according to AJCC clinical stage. Results: Average superoxide anion and malondialdehyde concentrations were significantly higher in melanoma patients than in control group, with the highest value of superoxide anion in stage III, while malondialdehyde highest value was in stage IV. The activity of total and manganese superoxide dismutase was insignificantly higher in melanoma patients than in control group, while catalase activity was significantly higher. The highest activity of total activity of manganese superoxide dismutase was in stage IV. Catalase activity was increasing with the disease progression achieving the maximum in stage III. Conclusion: Results of our study suggest that melanoma is oxidative stress associated disease, as well as deteriorated cell functioning at mitochondrial level.

P019. Melanoma in Balkan region: clinicopathological characteristics of 266 patients from the hospital-based registry in Serbia

Results: There were 152 males and 114 females, median age at diagnosis was 57 (13–86) years. The most frequent anatomic site was trunk in males (53.28%, P < 0.01) and lower extremities in females (32.46%, P < 0.01). The most frequent histopathological subtype was superficial spreading melanoma (SSM, 63.53%) and the ulceration was present in 40.6% of primary tumors. Mean Breslow thickness was 3.95 mm (median 3 mm, 0.1–25). Primary tumors of more then 4 mm thickness were found in 31.95% of patients. In this group of thick melanomas, statistically significant difference was found for younger age in SSM patients (55 vs. 61 years, P = 0.04). Of these, 10 patients (27.7%) were in 20–40 years group. Higher median Breslow thickness was found in patients with NM compared to SSM, as expected (7.5 vs. 5.55 mm, P = 0.039), and ulceration was present in 72/85 (84.71%) of these patients.