Tryptophan: Its Metabolism along the Kynurenine, Serotonin, and Indole Pathway in Malignant Melanoma.

(1) Background: Tryptophan metabolism is known to be one of the important mechanisms used by cancer to evade immune surveillance. Altered tryptophan metabolism was studied in patients with pigmented malignant melanoma confirmed histologically by the anatomic stage grouping for cutaneous melanoma using clinical staging on the basis of the Breslow thickness of the melanoma, the degree of spread to regional lymph nodes, and by the presence of distant metastasis. (2) Methods: Urinary tryptophan metabolites were detected by RP-HPLC method. (3) Results: In the present work, we provided evidence of altered metabolism of all tryptophan pathways in melanoma patients. (4) Conclusions: Knowledge of the shifted serotonin pathway toward DHICA formation and kynurenine pathway shifted toward NAD+ production could serve in the early detection of the disease and the initiation of early treatment of malignant melanoma.

Strong Dependence between Tryptophan-Related Fluorescence of Urine and Malignant Melanoma.

Urine autofluorescence at 295 nm is significantly higher in patients with malignant melanoma at each clinical stage compared to the healthy group. The largest difference is in the early-stages and without metastases. With increasing stage, the autofluorescence at 295 nm decreases. There is also a significant negative correlation between autofluorescence and Clark classification. Based on our results, it is assumed that the way malignant melanoma grows also affects urinary autofluorescence.

Specific Urinary Metabolites in Malignant Melanoma.

Background and objectives: Melanin, which has a confirmed role in melanoma cell behaviour, is formed in the process of melanogenesis and is synthesized from tryptophan, L-tyrosine and their metabolites. All these metabolites are easily detectable by chromatography in urine. Materials and Methods: Urine samples of 133 individuals (82 malignant melanoma patients and 51 healthy controls) were analysed by reversed-phase high-performance liquid chromatography (RP-HPLC). The diagnosis of malignant melanoma was confirmed histologically. Results: Chromatograms of melanoma patients showed increased levels of 5,6-dihydroxyindole-2-carboxylic acid, vanilmandelic acid, homovanilic acid, tryptophan, 5-hydroxyindole-3-acetic acid, and indoxyl sulphate compared to healthy controls. Concentration of indoxyl sulphate, homovanilic acid and tryptophan were significantly increased even in the low clinical stage 0 of the disease (indoxyl sulphate, homovanilic acid and tryptophan in patients with clinical stage 0 vs. controls expressed as medium/ interquartile range in µmol/mmol creatinine: 28.37/15.30 vs. 5.00/6.91; 47.97/33.08 vs. 7.33/21.25; and 16.38/15.98 vs. 3.46/6.22, respectively). Conclusions: HPLC detection of metabolites of L-tyrosine and tryptophan in the urine of melanoma patients may play a significant role in diagnostics as well as a therapeutic strategy of melanoma cancer.

Polymorphisms at 1q32, 8q24, and 17q22 loci are associated with nonsyndromic cleft lip with or without cleft palate risk in the Slovak population.

BACKGROUND: Nonsyndromic cleft lip with or without cleft palate (nsCL/P) is the most common orofacial birth defect with an aetiology involving both genetic and environmental factors. Genome-wide association studies (GWAS) have identified several genomic susceptibility regions for nsCL/P. In the present study, the three well established single nucleotide polymorphisms (SNPs) identified by GWAS (rs987525 at 8q24, rs7078160 at 10q25, and rs227731 at 17q22 loci) and one SNP identified by candidate gene study (rs642961 in IRF6 gene at 1q32 locus) were analysed for an association with nsCL/P in Slovak population. METHODS: Nucleotide variants were genotyped in 165 nsCL/P patients and 326 unaffected controls. All variants of interest were genotyped using high-resolution melting analysis after real-time PCR. RESULTS: We found significant differences between patient and control groups with respect to the allele and genotype frequencies for the SNPs at the 1q32, 8q24, and 17q22 loci. SNP at the 10q25 locus showed a trend toward association with nsCL/P risk. CONCLUSIONS: The results suggest that SNPs at the 1q32, 8q24 and 17q22 loci may contribute to the nsCL/P risk in Slovak population.

Epidemiological Study of Orofacial Clefts among Population of Eastern Slovakia during the Period 1996-2013.

BACKGROUND: Over the past 18 years, according to data from the Clinic of Plastic and Reconstructive Surgery, L. Pasteur University Hospital, there have been 493 cases of orofacial clefts (OC) reported in the area of Eastern Slovakia. The aim of this study was to map the occurrence of orofacial clefts reported in the area of Eastern Slovakia during the years 1996-2013. Also, we compared the occurrence of different types of clefts between the groups in relation to gender and ethnicity. METHODS AND RESULTS: The statistical analysis shows relationship between variables of location and gender and gender differences in the occurrence of various types of clefts. Moreover, in comparison with another study which analyzed the years 1985-2000 (1.29/10(3) live births), there was an increase in the incidence (1.42/10(3) live births) of OC in Eastern Slovakia. CONCLUSION: Our findings seem contradictive to similar studies which discuss ethnic differences in relation to OC. We recognize the relatively high occurrence of OC in Eastern Slovakia, and we link this phenomenon to several extrinsic factors, in particular socioeconomic status and embryotoxic factors.