microRNAs deregulation in head and neck squamous cell carcinoma.

Head and neck (HN) squamous cell carcinoma (SCC) is the eighth most common human cancer worldwide. Besides tobacco and alcohol consumption, genetic and epigenetic alterations play an important role in HNSCC occurrence and progression. microRNAs (miRNAs) are small noncoding RNAs that regulate cell cycle, proliferation, development, differentiation, and apoptosis by interfering in gene expression. Expression profiling of miRNAs showed that some miRNAs are upregulated or downregulated in tumor cells when compared with the normal cells. The present review focuses on the role of miRNAs deregulations in HNSCC, enrolled in risk, development, outcome, and therapy sensitivity. Moreover, the influence of single nucleotide variants in miRNAs target sites, miRNAs seed sites, and miRNAs-processing genes in HNSCC was also revised. Due to its potential for cancer diagnosis, progression, and as a therapeutic target, miRNAs may bring new perspectives in HNSCC understanding and therapy, especially for those patients with no or insufficient treatment options.

GSTM1, GSTT1 and GSTP1 Ile105Val polymorphisms in outcomes of head and neck squamous cell carcinoma patients treated with cisplatin chemoradiation.

Cisplatin (CDDP) combined with radiotherapy (RT) is employed in head and neck squamous cell carcinoma (HNSCC) with variable toxicities and clinical response. Glutathione S-transferases (GSTs) participate in CDDP excretion from cells, and genes encoding GSTs, GSTM1, GSTT1and GSTP1, are polymorphic in humans. This prospective study aimed to evaluate the roles of GSTM1, GSTT1, and GSTP1 Ile105Val polymorphisms in outcomes of HNSCC patients treated with CDDP chemoradiation. Ninety patients were genotyped by multiplex PCR. Urinary CDDP measurements were performed by HPLC. Treatment side effects and response were analysed by conventional criteria. Patients with GSTT1 genes showed 7.23- and 5.37-fold higher likelihood of presenting vomiting and ototoxicity, lower glomerular filtration rate (GFR), and lower elimination of CDDP in urine relative to patients with deleted genes. Patients harbouring the GSTP1 IleVal or ValVal genotypes showed 4.28-fold higher likelihood of presenting grade 2 or 3 vomiting and lower GFR with treatment than those harbouring the IleIle genotype. In multivariate Cox analysis, patients with the GSTP1 105ValVal genotype had 3.87 more chance of presenting disease progression than those with the IleIle or IleVal genotype (p < 0.01). Our findings provide preliminary evidence that inherited abnormalities in CDDP metabolism, related to GSTT1 and GSTP1 Ile105Val polymorphisms, alter outcomes of HNSCC patients treated with CDDP and RT.

PDCD1 gene polymorphisms as regulators of T-lymphocyte activity in cutaneous melanoma risk and prognosis.

This study aimed to evaluate whether PD1.1 (c.-606G>A), PD1 (c.627 + 252C>T), PD1.5 (c.804C>T), and PD1.9 (c.644C>T) single nucleotide polymorphisms of PDCD1 gene influence the risk, clinicopathological aspects, and survival of cutaneous melanoma (CM). Individuals with phototype I or II and PD1 CC genotype were under 5.89-fold increased risk of developing CM. PD1.5 TT genotype increased PDCD1 expression (2.49 versus 1.28 arbitrary units, p = .03) and PD1.5 CT or TT genotype and allele T increased PD1 expression in TCD4+ lymphocytes (16.6 versus 12.5%, p = .01; 17.0 versus 13.1%, p = .006). At 60 months of follow-up, short recurrence-free survival was seen in patients with PD1.1 AA genotype (33.3 versus 71.8%, p = .03). Patients with PD1.1 AA and PD1.5 CC genotype had 4.21 and 2.62 more chances of presenting relapse and evolving death by disease in Cox analyses, respectively. Our data provide preliminary evidence that abnormalities in regulation of T lymphocyte alter CM risk, clinical aspects, and prognosis.

Dietary risk factors for colorectal cancer in Brazil: a case control study.

BACKGROUND: High meat intake and low consumption of vegetables, fruits and whole grains have been associated with increased risk of colorectal cancer in some relevant cohort studies conducted in distinct ethnic populations. The role of the dietary pattern on the risk of sporadic colorectal adenocarcinoma (SCA) in Brazil is unknown; therefore, it was the aim of the present study. METHODS: The dietary patterns of 169 patients with SCA and 101 controls were analysed by food frequency recall. Crude odds ratios were calculated and given within 95 % confidence intervals. RESULTS: Patients reported higher average intakes of beef (32.0 ± 1.8 versus 23.7 ± 1.6, P = 0.0069), chicken (18.1 ± 0.9 versus 12.2 ± 0.8, P = 0.0002), and pork (8.9 ± 0.9 versus 3.4 ± 0.5, P < 0.0001). These individuals had a 1.025, 1.069, and 1.121-fold increased risk of SCA. Similar consumption of fish, vegetables, fruits and whole grains was reported by patients and controls. CONCLUSIONS: Meat consumption is greater in patients with SCA in the Brazilian population. Considering the study population - characterized by ethnic heterogeneity -, the environmental factor related to food habits may be associated with higher incidence of this disease in Brazil.

Polymorphisms in the 5'- and 3'-untranslated region of the VEGF gene and sporadic breast cancer risk and clinicopathologic characteristics.

The wild and the variant alleles of the C936T and G634C vascular endothelial grow factor (VEGF) polymorphisms seem to be linked to higher angiogenic phenotype than the remaining alleles and may act on breast cancer (BC) origin. We investigated the influence of the VEGF C936T and G634C polymorphisms on the occurrence and clinicopathologic characteristics of sporadic breast cancer (SBC) in 235 patients and 235 controls. Peripheral blood samples of all individuals were analysed by the polymerase chain reaction for identification of genotypes and by enzyme-linked immunosorbent assay (ELISA) for quantification of serum VEGF levels. The variant 634CC genotype isolated (16.2% versus 10.7%, P = 0.01) and in combination with the wild 936CC genotype (10.6% versus 5.5%, P = 0.01) were more common in patients than in controls. The carriers of the respective genotypes were under a 2.20-fold and a 3.08-fold increased risks for the disease. Additionally, the frequency of the wild 936CC genotype was higher in patients with tumours of histological grade III compared to those with tumours of I+II histological grades (84.0% versus 64.7%, P = 0.004) and in patients with positive oestrogen receptor tumours compared to those with tumours lacking oestrogen receptor expression (84.7% versus 73.9%, P = 0.02). Similar serum values of VEGF were seen in patients and controls with the distinct genotypes of the VEGF. The data suggest that the VEGF wild 936CC and the variant 634CC genotypes constitute inherited determinants of SBC and SBC aggressiveness in Brazil, but are not significant predictors of circulating VEGF levels.

Polymorphisms of glutathione S-transferase mu 1, theta 1, and pi 1 genes and prognosis in Hodgkin lymphoma.

We examined the influence of the glutathione S-transferase mu 1 (GSTM1), theta 1 (GSTT1), and pi 1 (GSTP1) polymorphisms, which are involved in the metabolism of alkylating agents and anthracyclines, on the outcome of patients with Hodgkin lymphoma (HL) treated with conventional chemotherapy. Genomic DNA from 125 consecutive cases was analyzed by polymerase chain reaction and enzymatic digestion for polymorphism determination. The GSTM1 undeleted genotype was associated with more advanced tumor stage and worse disease-free survival. The GSTT1 undeleted genotype was associated with higher recurrence rate. In contrast, higher toxicity of chemotherapy was attributed to absence of the GSTT1 gene. Concerning overall survival, lower tumor stage (p = 0.006) and International Prognostic Score (p = 0.02), lower peripheral leukocyte count (p = 0.0003), higher serum albumin level (p = 0.08), and GSTT1 undeleted genotype (p = 0.04) were predictive of a better outcome of patients. In multivariate analysis comparing staging and GST polymorphism, only tumor stage and GSTT1 genotype remained in the model. Our results suggest that the GSTT1 polymorphism influences the outcome of Brazilian patients with HL. However, studies of toxicity, pharmacokinetics, and protein function may clarify whether carriers of the distinct genotypes should receive different doses of chemotherapeutic agents.

The GSTT1 polymorphism of the glutathione S-transferase system in the intratumoral microvessel density of breast cancer patients.

It is well established that hypoxic microenvironment contributes to breast cancer progression by activation of transcriptional genes that promote angiogenesis. By promoting the antioxidant activity of glutathione, glutathione S-transferases (GSTs) are likely to facilitate the hypoxia-inducible factor-1α (HIF-1α) activity, therefore stimulating the angiogenesis. We investigated herein the influence of the GSTM1 and GSTT1 polymorphisms in the intratumoral angiogenesis of 87 patients with sporadic breast cancer. The intratumoral microvessel density (IMVD) of formalin-fixed paraffin-embedded tissues samples from all patients was determined by immunohistochemistry. The high IMVD was defined as a median microvessel counting higher than 18.7 after the analysis of histogram with all the results. The high IMVD was more common in patients with the GSTT1 wild genotype than in those with the GSTT1 null genotype (P = 0.04). Our results suggest, for the first time, that the GSTT1 polymorphism constitutes an inherited determinant of intratumoral angiogenesis in sporadic breast cancer.

Polymorphisms of glutathione S-transferase Mu 1, glutathione S-transferase theta 1 and glutathione S-transferase Pi 1 genes in Hodgkin's lymphoma susceptibility and progression.

We tested in this study whether the polymorphisms of the glutathione S-transferase Mu1 (GSTM1), glutathione S-transferase Theta 1 (GSTT1) and glutathione S-transferase Pi 1 (GSTP1), involved in metabolism of chemical agents, cell proliferation and cell survival, alter the risk for Hodgkin lymphoma (HL). Genomic DNA from 110 consecutive patients with HL and 226 controls was analysed by polymerase chain reaction and restriction digestion for the polymorphism analyses. Similar frequencies of the GSTM1 and GSTT1 genotypes were seen in patients and controls. In contrast, the frequency of the GSTP1 wild genotype (59.1%versus 36.3%, P = 0.004) was higher in patients than in controls. Individuals with the wild genotype had a 2.68 (95%CI: 1.38-5.21)-fold increased risk for the disease than others. An excess of the GSTP1 wild genotype was also observed in patients with tumors of stages III + IV when compared with those with tumors of stages I + II (39.1%versus 20.0%, P = 0.03). These results suggest that the wild allele of the GSTP1 gene is linked to an increased risk and high aggressiveness of the HL in our cases but they should be confirmed by further studies with larger cohorts of patients and controls.

A high risk of occurrence of sporadic breast cancer in individuals with the 104NN polymorphism of the COL18A1 gene.

We investigated the influence of the polymorphism D104N of the COL18A1 gene, encoding endostatin, on the occurrence of sporadic breast cancer in 181 patients and 448 controls. The homozygous 104NN polymorphism was found in five patients but was absent in controls (2.8% vs 0.0%; P = 0.002). Individuals with this genotype had a significantly increased risk for disease. Our results suggest, for the first time, that the homozygous 104NN polymorphism, even at low frequency, constitutes an important inherited determinant of the disease.

Inherited pericentric inversion of chromosome 16 in chronic phase of chronic myeloid leukaemia.

The simultaneous occurrence of two specific acquired chromosomal abnormalities in chronic or acute leukaemias is rare. Inherited chromosomal abnormalities are also rare events in the general population. In chronic myeloid leukaemia (CML), characterised by the t(9;22)(q34;q11), the inv(16)(p13q22) has been described associated with the acceleration of disease or onset of blast crisis. We report on a patient with chronic phase of CML and both acquired t(9;22)(q34;q11) and inherited inv(16)(p13q22), who obtained a complete remission of the disease after bone marrow transplant. Therefore, it is worth to comment that an additional chromosomal abnormality in disease does not obligatory mean transformation of the disease to a more aggressive form, since chromosomal abnormalities are also seen in normal individuals.