Increased glucose uptake mediated by glucose transporters and reliance on glycolysis are common features of malignant cells. Hypoxia-inducible factor-1α supports the adaptation of hypoxic cells by inducing genes related to glucose metabolism. The contribution of glucose transporter (GLUT) and hypoxia-inducible factor-1α (HIF-1α) activity to tumor behavior and their prognostic value in head and neck cancers remains unclear. The aim of this study was to examine the predictive value of GLUT1, GLUT3, and HIF-1α messenger RNA (mRNA)/protein expression as markers of tumor aggressiveness and prognosis in laryngeal cancer. The level of hypoxia/metabolic marker genes was determined in 106 squamous cell laryngeal cancer (SCC) and 73 noncancerous matched mucosa (NCM) controls using quantitative real-time PCR. The related protein levels were analyzed by Western blot. Positive expression of SLC2A1, SLC2A3, and HIF-1α genes was noted in 83.9, 82.1, and 71.7 % of SCC specimens and in 34.4, 59.4, and 62.5 % of laryngeal cancer samples. Higher levels of mRNA/protein for GLUT1 and HIF-1α were noted in SCC compared to NCM (p < 0.05). SLC2A1 was found to have a positive relationship with grade, tumor front grading (TFG) score, and depth and mode of invasion (p < 0.05). SLC2A3 was related to grade and invasion type (p < 0.05). There were also relationships of HIF-1α with pTNM, TFG scale, invasion depth and mode, tumor recurrences, and overall survival (p < 0.05). In addition, more advanced tumors were found to be more likely to demonstrate positive expression of these proteins. In conclusion, the hypoxia/metabolic markers studied could be used as molecular markers of tumor invasiveness in laryngeal cancer.

From our data we conclude that FGFR1 and FGFR3, as well as its downstream regulatory PI3K/AKT kinases, may serve as potential biomarkers for the invasiveness and prognosis of laryngeal cancer. The expression of FGFR1/3-PI3K/AKT regulatory pathway members may be instrumental for the identification of patients at risk for an unfavorable clinical outcome.

+ antigens expression in 21 h of experiments without mitogenic stimulation. Furthermore, this study revealed negative significant relationships of IFN-g secretion with regard to CD4

Metallothioneins are intracellular regulators of many biological mechanisms including differentiation, proliferation, angiogenesis and invasion, which are crucial processes in carcinogenesis. This study examines the association between three single-nucleotide polymorphisms at loci -5 A/G (rs28366003) and -209 A/G (rs1610216) in the core promoter region and at locus +838 C/G (rs10636) in 3'UTR region of the metallothionein 2A (MT2A) gene with squamous cell laryngeal cancer (SCLC) risk, as well as with tumor invasiveness according to tumor front grading (TFG). Genotyping was performed using the polymerase chain reaction-restriction fragment length polymorphism technique in 323 genetically unrelated individuals with SCLC and 418 randomly selected healthy volunteers. Only one SNP (rs28366003) was significantly related to laryngeal cancer in the study population. Compared with homozygous common allele carriers, heterozygous and homozygous for the G variant had significantly increased risk of SCLC [adjusted odds ratio (OR) = 2.90, 95 % confidence interval (CI) 1.53-5.21, p dominant < 0.001]. The A/G allele carriers at rs28366003 MT2A were at higher risk of SCLC development (OR = 2.63, 95 % CI 1.41-2.85, p < 0.001]. There was a significant association between the rs28366003 and stage and TFG classification. Most carriers of minor allele had a higher stage (OR = 2.76, 95 % CI 1.11-7.52, p = 0.03), increased cancer aggressiveness, as defined by a higher total TFG score (>18 points) (OR = 3.76, 95 % CI 1.15-12.56, p = 0.03) and diffuse tumor growth (OR = 5.86, 95 % Cl 0.72-44.79, p = 0.08). The results of this study raise a possibility that a genetic variation of MT2A may be implicated in the etiology of laryngeal cancer in a Polish population.

Enhancer of zest homolog 2 (EZH2) is a histone methyltransferase which plays a crucial role in cancer progression by regulation of genes involved in cellular processes such as proliferation, invasion and self-renewal. Activity and biological function of EZH2 are regulated by posttranslational modifications. It is suggested that EZH2 stability may be regulated by O-GlcNAc transferase (OGT), which is an enzyme catalyzing the addition of GlcNAc moieties to target proteins. In this study, we determined the impact of OGT on expression of EZH2 target genes FOXA1 and FOXC1, that are involved in breast cancer progression. The results of chromatin immunoprecipitation experiments showed that both EZH2 and OGT are targeted to the promoter regions of FOXA1 and FOXC1 and knockdown of EZH2 or OGT affects expression of studied genes in breast non-malignant (MCF10A) and cancer cells (MCF7, T47D and MDA-MB-231). The results showed that OGT silencing affects EZH2 binding to FOXC1 promoter but the effect is cell-context dependent. Despite the slight decrease in EZH2 protein level in cells with OGT depletion, EZH2 binding to FOXC1 was increased. Moreover, OGT binding to promoter regions of FOXA1 and FOXC1 was increased in cells with knockdown of EZH2. Increased expression of FOXA1 and FOXC1 in cells with OGT deregulation was associated with increased acetylation level of histone H3. The results suggest that OGT is involved in regulation of FOXA1 and FOXC1 expression but its role is not associated with regulation of EZH2 protein stability.