Peritumor Mucosa in Advanced Laryngeal Carcinoma Exhibits an Aberrant Proangiogenic Signature Distinctive from the Expression Pattern in Adjacent Tumor Tissue

The field cancerization theory is an important paradigm in head and neck carcinoma as its oncological repercussions affect treatment outcomes in diverse ways. The aim of this study is to assess the possible interconnection between peritumor mucosa and the process of tumor neoangiogenesis. Sixty patients with advanced laryngeal carcinoma were enrolled in this study. The majority of patients express a canonical HIF-upregulated proangiogenic signature with almost complete predominancy of HIF-1α overexpression and normal expression levels of the HIF-2α isoform. Remarkably, more than 60% of the whole cohort also exhibited an HIF-upregulated proangiogenic signature in the peritumoral benign mucosa. Additionally, the latter subgroup had a distinctly shifted phenotype towards HIF-2α upregulation compared to the one in tumor tissue, i.e., a tendency towards an HIF switch is observed in contrast to the dominated by HIF-1α tumor phenotype. ETS-1 displays stable and identical significant overexpression in both the proangiogenic phenotypes present in tumor and peritumoral mucosa. In the current study, we report for the first time the existence of an abnormal proangiogenic expression profile present in the peritumoral mucosa in advanced laryngeal carcinoma when compared to paired distant laryngeal mucosa. Moreover, we describe a specific phenotype of this proangiogenic signature that is significantly different from the one present in tumor tissue as we delineate both phenotypes, quantitively and qualitatively. This finding is cancer heterogeneity, per se, which extends beyond the "classical" borders of the malignancy, and it is proof of a strong interconnection between field cancerization and one of the classical hallmarks of cancer-the process of tumor neoangiogenesis.

A Genetic Risk Score to Personalize Prostate Cancer Screening, Applied to Population Data

BACKGROUND

A polygenic hazard score (PHS), the weighted sum of 54 SNP genotypes, was previously validated for association with clinically significant prostate cancer and for improved prostate cancer screening accuracy. Here, we assess the potential impact of PHS-informed screening.

METHODS

United Kingdom population incidence data (Cancer Research United Kingdom) and data from the Cluster Randomized Trial of PSA Testing for Prostate Cancer were combined to estimate age-specific clinically significant prostate cancer incidence (Gleason score ≥7, stage T3-T4, PSA ≥10, or nodal/distant metastases). Using HRs estimated from the ProtecT prostate cancer trial, age-specific incidence rates were calculated for various PHS risk percentiles. Risk-equivalent age, when someone with a given PHS percentile has prostate cancer risk equivalent to an average 50-year-old man (50-year-standard risk), was derived from PHS and incidence data. Positive predictive value (PPV) of PSA testing for clinically significant prostate cancer was calculated using PHS-adjusted age groups.

RESULTS

The expected age at diagnosis of clinically significant prostate cancer differs by 19 years between the 1st and 99th PHS percentiles: men with PHS in the 1st and 99th percentiles reach the 50-year-standard risk level at ages 60 and 41, respectively. PPV of PSA was higher for men with higher PHS-adjusted age.

CONCLUSIONS

PHS provides individualized estimates of risk-equivalent age for clinically significant prostate cancer. Screening initiation could be adjusted by a man's PHS.

IMPACT

Personalized genetic risk assessments could inform prostate cancer screening decisions.

Proangiogenic signature in advanced laryngeal carcinoma after microRNA expression profiling

The aim of this study is to evaluate which dysregulated angiomiRs compose the specific proangiogenic microRNA signature of advanced laryngeal cancer and review the literature. Thirty-six samples from twelve patients with advanced laryngeal carcinoma were collected. Total RNA was extracted and microRNA global profiling was performed using Agilent Technologies Microarray Kit. Fifty-nine microRNAs were found to have significantly different expression levels. Eleven microRNAs from the whole group were sorted as regulators of tumor angiogenesis (angiomiRs): seven were up-regulated-miR-1246, miR-181b 5p, miR-18a 5p, miR-21 3p, miR-210 3p, miR-503 5p, miR-93 5p and four were down-regulated-miR148a 5p, miR-145 5p, miR-204 5p, miR-125b 5p. For none of those microRNAs we found heterogeneity in tumor tissue. We are the first to report the specific proangiogenic microRNA signature in advanced laryngeal carcinoma and we confirm and amplify findings from previous studies that expand our perception of a specific "molecular state" of angiogenesis that is distinctive only for laryngeal cancer.

The Role of miRNAs and lncRNAs in Laryngeal Squamous Cell Carcinoma - a Mini-Review

Laryngeal squamous cell carcinoma is a common malignancy in men. Bulgaria is one of the countries in Europe with the highest incidence and mortality rates of the aggressive, severe disease of laryngeal cancer. Proven etiological factors are the abuse of tobacco and alcohol beverages. Despite the progress of technologies of multimodal medical treatment, survival rates have not reached satisfactory levels. Over the last few decades, scientific and clinical research data have led to a growing interest in exploring potential biomarkers. In the last years, non-coding RNAs have become promising biomarkers. They are important key regulators in both normal and tumour specific biological processes as well as in the response to environmental factors and treatment, including chemo- and radiotherapy. Studies have shown ectopic expression of a number of ncRNAs in laryngeal cancer. Published data provide evidence of the lncRNAs and miRNAs that could help us better understand complex carcinogenesis in laryngeal cancer and would provide reliable diagnostic, prognostic and predictive biomarkers.

First Report of DHA-1 Producing Enterobacter cloacae Complex Isolate in Bulgaria

The aim of the present study was to reveal the characteristics of an Enterobacter cloacae complex isolate producing DHA-1 AmpC enzyme recovered from a patient hospitalized in St Marina Hospital, Varna.

Materials and methods: Susceptibility testing, conjugation experiments, isoelectric focusing, PCR and sequencing were carrying out.

Results: Of 176 Enterobacter spp. isolates only one isolate was positive for blaDHA. The sequencing revealed the presence of blaDHA-1 and blaCTX-M-3. The antimicrobial susceptibility testing showed higher resistance rates to almost all beta-lactams (ceftazidime, cefotaxime, cefepime, amoxicillinclavulanic acid, piperacillin/tazobactam), tobramycin, gentamycin, trimethoprim/sulphomethoxazole and quinolones (ciprofloxacin and levofloxacin). The isolate was susceptible to imipenem, meropenem and amikacin. The isoelectric focusing showed a band at pI 5.4 without ceftazidime and cefotaxime activity; a band at pI 7.8 with cefoxitin activity and another - with pI 8.4 with cefotaxime activity. Conjugation experiments were successful only for blaCTX-M-3 carrying determinants. 

Conclusions: To the best of our knowledge this is the first report of DHA-1 producing isolate in Bulgaria. The emergence of DHA-1 producing E. cloacae complex demonstrates the possibility for further dissemination of the gene encoding this enzyme. Infectious control measures are needed for the prevention of this phenomenon.

Circulating Metabolic Biomarkers of Screen-Detected Prostate Cancer in the ProtecT Study

BACKGROUND

Whether associations between circulating metabolites and prostate cancer are causal is unknown. We report on the largest study of metabolites and prostate cancer (2,291 cases and 2,661 controls) and appraise causality for a subset of the prostate cancer-metabolite associations using two-sample Mendelian randomization (MR).

METHODS

The case-control portion of the study was conducted in nine UK centers with men ages 50-69 years who underwent prostate-specific antigen screening for prostate cancer within the Prostate Testing for Cancer and Treatment (ProtecT) trial. Two data sources were used to appraise causality: a genome-wide association study (GWAS) of metabolites in 24,925 participants and a GWAS of prostate cancer in 44,825 cases and 27,904 controls within the Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium.

RESULTS

Thirty-five metabolites were strongly associated with prostate cancer (P < 0.0014, multiple-testing threshold). These fell into four classes: (i) lipids and lipoprotein subclass characteristics (total cholesterol and ratios, cholesterol esters and ratios, free cholesterol and ratios, phospholipids and ratios, and triglyceride ratios); (ii) fatty acids and ratios; (iii) amino acids; (iv) and fluid balance. Fourteen top metabolites were proxied by genetic variables, but MR indicated these were not causal.

CONCLUSIONS

We identified 35 circulating metabolites associated with prostate cancer presence, but found no evidence of causality for those 14 testable with MR. Thus, the 14 MR-tested metabolites are unlikely to be mechanistically important in prostate cancer risk.

IMPACT

The metabolome provides a promising set of biomarkers that may aid prostate cancer classification.

Macrophageal infiltration and microvessel density in laryngeal carcinoma: study of 52 cases

Angiogenesis is one of the six originally constituted hallmarks of cancer that has been extensively studied in the last two decades. The aim of our study is to assess the microvessel and macrophageal density in laryngeal carcinoma and its clinicopathological correlations. We immunohistochemically assessed microvessel density (CD34) and macrophage count (CD68) using microarray techniques and then looked for clinicopathological correlations. The mean micro-vessel density in the study group was 14.27 ± 12.92 vessels in a ×200 field with a mean macrophageal infiltration density of 5.19 ± 4.32. Median microvessel density was significantly higher in patients with metastasis than in patients without metastasis. Additionally, linear regression established that macrophageal infiltration density could predict microvessel density in laryngeal carcinoma. We found no association between either factor and recurrence rate or other clinical characteristics. Our study adds additional data to a problem that has been widely studied during the last two decades, even if controversies in this area still remain.

Genome-wide association study of prostate cancer-specific survival

BACKGROUND

Unnecessary intervention and overtreatment of indolent disease are common challenges in clinical management of prostate cancer. Improved tools to distinguish lethal from indolent disease are critical.

METHODS

We performed a genome-wide survival analysis of cause-specific death in 24,023 prostate cancer patients (3,513 disease-specific deaths) from the PRACTICAL and BPC3 consortia. Top findings were assessed for replication in a Norwegian cohort (CONOR).

RESULTS

We observed no significant association between genetic variants and prostate cancer survival.

CONCLUSIONS

Common genetic variants with large impact on prostate cancer survival were not observed in this study.

IMPACT

Future studies should be designed for identification of rare variants with large effect sizes or common variants with small effect sizes.

Risk Analysis of Prostate Cancer in PRACTICAL, a Multinational Consortium, Using 25 Known Prostate Cancer Susceptibility Loci

BACKGROUND

Genome-wide association studies have identified multiple genetic variants associated with prostate cancer risk which explain a substantial proportion of familial relative risk. These variants can be used to stratify individuals by their risk of prostate cancer.

METHODS

We genotyped 25 prostate cancer susceptibility loci in 40,414 individuals and derived a polygenic risk score (PRS). We estimated empirical odds ratios (OR) for prostate cancer associated with different risk strata defined by PRS and derived age-specific absolute risks of developing prostate cancer by PRS stratum and family history.

RESULTS

The prostate cancer risk for men in the top 1% of the PRS distribution was 30.6 (95% CI, 16.4-57.3) fold compared with men in the bottom 1%, and 4.2 (95% CI, 3.2-5.5) fold compared with the median risk. The absolute risk of prostate cancer by age of 85 years was 65.8% for a man with family history in the top 1% of the PRS distribution, compared with 3.7% for a man in the bottom 1%. The PRS was only weakly correlated with serum PSA level (correlation = 0.09).

CONCLUSIONS

Risk profiling can identify men at substantially increased or reduced risk of prostate cancer. The effect size, measured by OR per unit PRS, was higher in men at younger ages and in men with family history of prostate cancer. Incorporating additional newly identified loci into a PRS should improve the predictive value of risk profiles.

IMPACT

We demonstrate that the risk profiling based on SNPs can identify men at substantially increased or reduced risk that could have useful implications for targeted prevention and screening programs.

Mutational Status of CDKN2A and TP53 Genes in Laryngeal Squamous Cell Carcinoma

Laryngeal squamous cell carcinoma (LSCC) is the second most common tumour of the head and neck. It is characterized by frequent aberrations in two cell-cycle regulators--CDKN2A and TP53. However, LSCC has been often studied as a part of the group of head and neck cancers and not as an individual entity. In the current study we aimed to examine mutation status of CDKN2A and TP53 genes in 108 LSCC patients. DNA was extracted from fresh-frozen tumour tissues; exons 1-3 of CDKN2A and exons 5-8 of TP53 were screened for mutations by direct sequencing. Genetic aberrations in CDKN2A were found in 16 (14.2%) and those in TP53--in 56/108 (51.9%) tumours. Seven mutations (two insertions, three deletions, one missense and one silent) detected in CDKN2A were not described previously. Also, we found seven novel deletions and a novel indel in TP53. No significant associations with clinical features were found. However, TP53 mutations were predominantly observed in smokers with advanced stage tumours. Screening for genetic aberrations in a defined group of LSCC contributes to the knowledge about laryngeal carcinogenesis. Further investigations are required to confirm the observed trends in associations with clinical features.

Promoter hypermethylation of CDKN2A, MGMT, MLH1, and DAPK genes in laryngeal squamous cell carcinoma and their associations with clinical profiles of the patients

BACKGROUND

Laryngeal squamous cell carcinoma (laryngeal SCC) is a frequently occurring cancer of the head and neck area. Epigenetic changes of tumor-related genes contribute to its genesis and progression.

METHODS

We assessed promoter methylation status of the selected genes (CDKN2A, MGMT, MLH1, and DAPK) using methylation-sensitive high resolution melting (MS-HRM) in 100 patients with laryngeal SCC and studied the correlations with clinical characteristics.

RESULTS

The prevalence of promoter methylation in MGMT, CDKN2A, MLH1, and DAPK was 59 of 97 (60.8%), 46 of 97 (47.4%), 45 of 97 (46.4%), and 41 of 97 patients (42.3%), respectively. Significantly increased methylation of CDKN2A was observed in heavy smokers. Epigenetic inactivation of CDKN2A and MLH1 were found to be associated with lymph node involvement. An inverse correlation was present between MLH1 methylation and alcohol consumption.

CONCLUSION

Our results strongly suggest that deregulation of p16-associated, and MLH1-associated pathways, because of promoter hypermethylation, is associated with increased cancer cell migration, tumor invasiveness, and, thus, aggressive phenotype.

No evidence of association between 118A>G OPRM1 polymorphism and heroin dependence in a large Bulgarian case-control sample

The μ-opioid receptor is the primary site of action of most opioids. The 118A>G (rs1799971) polymorphism in exon 1 of the μ-opioid receptor gene (OPRM1) leads to an Asn40Asp amino acid change that affects a putative N-glycosylation site. It has been widely investigated for association with alcohol and drug dependence and pain sensitivity, with mixed results. The aim of the current study was to examine whether this polymorphism was associated with heroin dependence in a large Bulgarian cohort of 1842 active users and 1451 population controls. SNP genotyping was done using Real-Time PCR TaqMan technology. Association analyses were conducted, separately for Roma and non-Roma participants. Our results suggest that there is no direct effect of 118A>G genotype on the risk for heroin dependence among active heroin users.

Microsatellite instability in Bulgarian patients with endometrial cancer

PURPOSE

Microsatellite instability (MSI) is a frequent event in different types of cancer. In several studies MSI was shown to have both clinical and prognostic value. The aim of our study was to determine the frequency of MSI in Bulgarian patients with endometrial cancer (EC) and the possible relation of this phenomenon to their clinicopathological characteristics.

PATIENTS AND METHODS

A total of 33 histologically confirmed EC patients were analyzed for tumor MSI using a panel of 6 microsatellite markers.

RESULTS

We identified MSI in 30% of endometrial cancer cases. Six of them had high degree of MSI (MSI-H), and 4 displayed low degree of MSI (MSI-L).

CONCLUSION

The frequency of MSI in Bulgarian EC patients does not differ significantly from that reported in other European studies.

Linkage analysis in bipolar pedigrees adds support for a susceptibility locus on 21q22

Several studies provide suggestive evidence of a susceptibility locus for bipolar disorder at chromosome 21q22-23. In an attempt to replicate these findings, we have analyzed linkage to 11 polymorphic markers from this region in 18 Bulgarian pedigrees with affective disorder. Two-point linkage analysis under assumption of homogeneity and a dominant model with reduced penetrance produced modest positive values for some of the markers tested under a 'narrow' phenotype definition, including bipolar I and II, and schizoaffective disorder. The maximum two-point score (lod=1.76, theta=0.00) was at marker D21S1919. Non-parametric linkage analysis under the same phenotype model, yielded positive NPLall values (P<0.05) over the region between markers D21S211 and D21S416, with a peak at D21S1252 (NPL Zall=2.32, P=0.0003). The multipoint lod score (GENEHUNTER) reached a suggestive value for linkage (lod=2.10) also at marker D21S1252. The results under a recessive model were completely negative. These data add to the evidence for the existence of a susceptibility locus for bipolar affective disorder on chromosome 21q22.

Expression of the nuclear protein mitotin in differentiating in vitro HL 60 cells

Mitotin is a 125 kDa/pI 6.5 nuclear protein specific for proliferating cells and markedly increased prior to and during mitosis. This study presents evidence for the expression of this protein during dimethylsulfoxide (DMSO) induced differentiation of human promyelocytic leukemia HL 60 cells. The expression had been followed at two levels: as antigen, using a specific antimitotin monoclonal antibody and as mRNA, using a specific cDNA probe. The results from the immunofluorescent study show a gradual disappearance of mitotin in differentiating HL 60 cells starting from the fourth day after DMSO induction. On the other hand, the changes in the expression of mitotin mRNA were much more dramatic. This mRNA is expressed at a high level during the first three days of differentiation but shows a striking decrease after the fourth day. This correlates with the rapid changes in the number of blast cells in the differentiating HL 60 cell population. Therefore, the expression of mitotin mRNA can serve as a marker for the changes accompanying the termination of cell proliferation in differentiating cells.