FACTORS ASSOCIATED WITH PERSISTENCE OF HPV GENITAL INFECTION IN A SMALL COHORT OF ROMANIAN WOMEN.

The aim of the study was to assess the role of behavioral factors in persistence of human papillomavirus (HPV) genital infection. Out of a cohort of 605 women included in a study of HPV infection prevalence, 142 HPV positive women (aged 18-57) were retested after a 12-month interval. None of the patients underwent surgical treatment during that period. Selected patients were asked for a second smear for cytologic analysis and HPV genotyping. A questionnaire that included information regarding reproductive health, sexual activity and smoking status was filled-in. After 12 months, 46 of 142 (32.39%) women had persistent HPV infection, with genotypes 16 and 18 found in 27 cases. On the other hand, 17 of 142 (11.97%) women had acquired new infections replacing the baseline genotypes. In our study, smoking (OR=2.320, p=0.0330) and sexual behavior (OR=5.333, p=0.0180 for more than three sexual partners; OR=2.427, p=0.0238 for cases where the partner was involved in another sexual relationship) were associated with viral persistence, while long-term contraception did not yield statistically significant results.

LINC01101 and LINC00277 expression levels as novel factors in HPV-induced cervical neoplasia.

Recently long non-coding RNAs were identified as new factors involved in gene expression regulation. To gain insight into expression pattern of these factors related to E7 HPV18 oncogene, this study uses HeLa cell culture transfected with E7-siRNA. Gene expression profile was investigated using microarray analysis. After analysing the microarray results, we identified 15,387 RNA species differentially expressed in E7-siRNA-transfected cells compared with controls (fold change >2). The expression profiles of lncRNA species highlighted 731 lncRNAs and 203 lincRNAs. We selected two lincRNAs (LINC01101 and LINC00277) and we evaluated the expression profile in HPV-induced neoplasia. Both lincRNAs investigated display a significantly reduced pattern of expression in cervical lesions and cancer, associated with clinical parameters. A connection between HPV presence and lincRNAs was noted. hrHPV-positive samples exhibit significantly reduced LINC01101 and LINC00277 expression level (P < 0.05). These results provide new insights into involvement of lncRNA in HPV-induced cervical cancer, enriching our understanding of their potential role in this pathology.

E5HPV16 mRNA EXPRESSION PATTERN ANALYSIS IN PATIENTS WITH CERVICAL LESIONS IN VIRAL STATUS CONTEXT.

Human papilloma virus (HPV) may cause mostly transient infections of cutaneous and mucous epithelia. Persistent HPV genital infections may induce pre-malignant or malignant lesions. While E6 and E7 HPV genes' malignant character is known, E5 is still under debate. We evaluated the possible role of E5 gene in cervix oncogenesis, in patients with abnormal cytology and HPV1 6 positive, in the context of viral status correlated with potential targets (p21, EGFR). HPV DNA was detected and genotyped using Linear Array HPV Genotyping Test (Roche Molecular Biochemicals, Mannheim, Germany) and E2, E6, E5 HPV16, p21 and EGFR transcripts levels were investigated by qRT-PCR. Our results indicate a significantly high E5 expression in low grade cytology, expression correlated with a moderated E6 and low p21 levels. All HSIL specimens presented integrated/mixed viral forms; mixed forms presented moderate E5 expression, high levels of p21 correlates with E6 oncogene high expression. These findings indicate a potential role for E5 pattern of expression in discriminating be-tween lesions that may progress to cancer.

Molecular variants of human papilloma virus 16 E2, E4, E5, E6 and E7 genes associated with cervical neoplasia in Romanian patients.

The aim of this study was to identify and associate the sequence variations of human Papillomavirus 16 (HPV16) genes from women who live in two different areas of Romania and associate them with malignant progression. One hundred twenty-four HPV16-positive cervical isolates were collected, and the E2, E4, E5, E6 and E7 viral genes were sequenced. Two new missense mutations in the E6 gene (C279G and A305C) were found (together or alone, in association with other mutations) in 44 of 124 cases. The most frequently simultaneously mutated genes were E4/E2 hinge, E5 and E6 (p = 0.0004) in squamous cell carcinoma (SCC) samples. Also, for SCC patients, the best-correlated mutation patterns were obtained for E4/E2 hinge-E5 (r = 0.7984; p < 0.0001). No sample was found to have all of the investigated viral genes concurrently mutated. Phylogenetic analysis was performed to characterize the viral variants. Similar results were found for SCC and cervical intraepithelial neoplasia III (CINIII) cases. After all of the target gene sequences were assembled, all patients were found to be infected with viruses of the HPV16- European-German (EG) lineage, and two clusters were identified, the first (55/96 variants) from Moldavia and the second (41/96 variants) from Bucharest. The distinct cluster derived from EG in Moldavia could partially explain the increased frequency of SCC in this area. This study has generated a comprehensive set of sequence variation data on HPV16 circulating in Romania to join the existing data and highlight the important role of HPV16 variants during cervical carcinogenesis.

Methylenetetrahydrofolate reductase (MTHFR) polymorphisms and promoter methylation in cervical oncogenic lesions and cancer.

The aim of this study was to investigate the role of methylenetetrahydrofolate reductase (MTHFR) polymorphisms and MTHFR methylation pattern in cervical lesions development among women from Romania, a country with high prevalence of human papillomavirus (HPV) cervical infections. To achieve this goal, blood samples and cervical cytology specimens (n = 77)/tumour tissue specimens (n = 23) were investigated. As control, blood and negative cytological smears (n = 50) were used. A statistically significant association was found between T allele of C677T polymorphism and cervical lesions, heterozygote women presenting a threefold increased risk (normal/cervical lesions and tumours: wild homozygote 34/41 (0.68/0.41), heterozygote 14/51 (0.28/0.51), mutant homozygote 2/8 (0.04/0.08); OR = 3.081, P = 0.0035). Using χ square test for the control group, the HPV-negative and HPV-positive patients with cervix lesions, a significant correlation between viral infection and T allele of C677T polymorphism (P = 0.0287) was found. The MTHFR promoter was methylated in all HGSIL and tumour samples, significant differences being noted between HPV-positive samples, control group and cases of cervical dysplastic lesions without HPV DNA (P < 0. 0001) and between samples from patients with high-risk (hr)HPV versus low-risk (lr)HPV (P = 0.0026). No correlations between polymorphisms and methylation were observed. In Romania, individuals carrying T allele are susceptible for cervical lesions. MTHFR promoter methylation is associated with cervical severity lesions and with hrHPV.

Mitochondrial DNA mutations in patients with HRHPV-related cervical lesions.

High risk human papillomaviruses (hr-HPV) are known to be the etiological agents of cervical cancer disease. On the other hand, other cofactors are considered to be important in cervix carcinogenesis. Mutations in mitochondrial DNA (mtDNA) as well as alterations in mtDNA content have been reported in numerous cancers examined to date. The D-loop region has been shown to be a mutational "hot spot" in human cancer. In order to evaluate the role of mtDNA mutations in cervical lesions progression, cervical specimens (from 79 women, 29-65 years old) were investigated. DNA was isolated (High Pure PCR Template, Roche Diagnostics) from cervical cells from patients with different cytology (normal cervical epithelium, ASCUS-Atypical Squamous Cells of Undetermined Significance, LGSIL-Low-Grade Intraepithelial Lesion, HGSIL-High-Grade Intraepithelial Lesion and SCC-Squamous Cell Carcinoma) and tested for HPV DNA presence (Linear Array HPV Genotyping Test, Roche Diagnostics). To elucidate a causative role of mtDNA in cervical lesions, mtDNA mutations were investigated using Mutector mtDNA kit (TrimGen Corporation). In patients with normal and ASCUS cytology, mtDNA mutations were absent. 16.66% of LGSIL patients presented mutations in D-loop region whereas 28.57% HGSIL cases showed mutations in mtDNA. Mutations were detected in 66.66% cases of SCC cases. These studies provide strong evidence that instability in the D-loop region of mtDNA may be involved in cervical dysplasia. We suggested that mtDNA mutations may play a role in cervical precursor lesions and cancer but their role in the mechanism of carcinogenesis remains to be solved.

The association between lncRNA H19 and EZH2 expression in patients with EBV-positive laryngeal carcinoma.

OBJECTIVE: Laryngeal cancer is the second most common malignancy in the head and neck, with Epstein-Barr virus infection as a risk factor. Our aim is to evaluate correlations between the expression of lncRNA H19 and EBV infection in laryngeal cancer and H19 involvement in neoplastic progression through EZH2 association. MATERIALS AND METHODS: 30 paired laryngeal tissue specimens (neoplastic and non-neoplastic) were included in the study. Nucleic acid isolation and cDNA synthesis was performed according to the manufacturer's protocol. EBV DNA and expression of lytic (BZLF1) and latent (LMP1) forms of infection were assessed in PCR assays; expression levels of H19 and EZH2 were quantified in qRT-PCR. Data was analysed using GraphPad Prism 5.0. RESULTS: Higher H19 relative expression in neoplastic vs paired non-neoplastic samples was found (p < 0.0001) with a significant increase in EBV DNA positive neoplasms (p = 0.0434). An inverse correlation between H19 and EZH2 expression levels was noticed in EBV positive cases. Additionally, increased levels of H19 in LMP1 positive samples compared with those positive for BZLF1 was found (p = 0.0593). CONCLUSIONS: lncRNA H19 and EZH2 significantly contribute to the development of laryngeal carcinoma, being correlated with EBV infection markers.

TGF-beta signalling pathway factors in HPV-induced cervical lesions.

Human papillomaviruses (HPV) are considered the etiological agents of cervical cancer, especially high-risk genotypes. TGF-beta (transforming growth factor-beta) is well known for its anti-proliferative effects but the neoplastic cells often lose their sensitivity to TGF-beta. A characteristic alteration associated with malignant progression is the loss of responsiveness to TGF-beta1-induced cell growth inhibition. The aim of the present study was to establish the possible role of some members of TGF-beta signalling pathway during cervical cancer development and the possible relationship with HPV infection. In order to establish TGF-beta gene expression levels in cervical oncogenesis, TGF-beta1, TGF-beta1 receptors and Smad2 were investigated in precancerous and cervical cancer samples (Quantitative Real-Time PCR). The study revealed that 84.5% of patients were positive for HPV DNA. The most prevalent HPV genotypes were high-risk HPV 16 and 18 in single or co-infections. Expression of TGF-beta1 decreased as tumor cells progressed from cervical intraepithelial neoplasia to cervical carcinoma. Furthermore, we observed that cervical lesions without HPV infection expressed significantly less TGF-beta1. TGF-betaRI and Smad2 gene expression levels were found to be decreased in SCC and AC samples in contrast with CIN1 and CIN2/3 samples. Our results showed that in human cervical cancer the disruption of TGF-beta/Smad signalling pathway might contribute to the malignant progression of cervical dysplasia. These data emphasize the importance of canonical TGF-beta pathway integrity in carcinogenesis.

Alterations of regulatory factors and DNA methylation pattern in thyroid cancer.

PURPOSE: DNA methylation plays an important role in thyroid oncogenesis. The aim of this study was to investigate the connection between global and local DNA methylation status and to establish the levels of important DNA methylation regulators (TET family and DNMT1) in thyroid tumours: follicular adenoma-FA, papillary thyroid carcinoma-PTC (classic papillary thyroid carcinoma-cPTC and papillary thyroid carcinoma follicular variant fvPTC). METHODS: Global DNA methylation profile in thyroid tumours tissue (41 paired samples) was assessed by 5-methylcytosine and 5-hydroxymethylcytosine levels evaluation (ELISA), along with TETs and DNMT1 genes expression quantification. Also, it was investigated for the first time TET1 and TET2 promoter's methylation in thyroid tumours. BRAF V600E mutation and RET/PTC translocation testing were performed on all investigated samples. In vitro studies upon DNA methylation in K1 thyroid cancer cells were performed with demethylating agents (5-AzaC and vitamin C). RESULTS: TET1 and TET2 displayed a significantly reduced gene expression level in PTC, while DNMT1 gene presented a high level of expression. PTC samples presented increased levels of 5-methylcytosine and low levels of 5-hydroxymethylcytosine. 5-methylcytosine levels were associated with TET1/TET2 expression levels. TET1 gene expression was significantly lower in patients positive for BRAF mutation and with RET/PTC rearrangement. TET2 gene was found hypermethylated in thyroid carcinoma patients overall, especially in PTC-follicular variant samples (p= 0.0002), where TET2 gene expression levels were significantly reduced (p= 0.0031). Furthermore, the data indicate for all thyroid cancer patients a good sensitivity (81.08%) and specificity (86.49%) regarding the use of TET1 (p< 0.0001), and TET2 (71.79%, 64.10%, p= 0.0001) hypermethylation as biomarkers for thyroid oncogenesis. CONCLUSIONS: These results suggest that TET1/TET2 gene expression and methylation may serve as potential diagnostic tools for thyroid neoplasia. Our study showed that the methylation of TET1 increases in malignant thyroid tumours. fvPTC patients presented lower methylation levels compared to cPTC and could be a discriminatory factor between two cancer types and benign lesions. TET2 is a poorer discriminator between FA and fvPTC, but it can be useful for cPTC identification. K1-cells treated with demethylating agents showed a demethylation effect, especially upon TET2 gene. The cumulative effect of L-AA and 5-AzaC proved to have a potent combined demethylating effect on genes promoter's activation and could open new perspectives for thyroid cancer therapy.

The relationship between HPV16 and HPV18 viral load and cervical lesions progression.

UNLABELLED: Cervical cancer remains one of the most important mortality causes worldwide. It is already known that high risk HPV (HR-HPV) has the main role in the development of pre- or cancerous lesions. Despite the fact that many studies focused on the HR-HPV viral loads as possible biomarkers, the viral load quantification utility for all HR-HPV genotypes is still a controversy. The purpose of our study was to determine if HPV16 and 18 viral load values might be a potential marker for HPV infection clearance versus of pre- and cancerous lesions development. MATERIALS AND METHODS: 80 women who tested positive for HPV16 and 18 were selected from a cohort of 250 patients. The samples, consisting in cervical smears, were collected in transport media ESwab (Copan). The patient's average age was 36.26 years. HPV DNA detection, genotyping and viral load determination were performed twice for each patient (within one year follow-up). RESULTS: HPV 16 viral load was significantly higher in normal cytology samples and in HGSIL patients than in ASCUS/LGSIL (p value < 0.0312). HPV 18 viral load was also significantly higher in HGSIL cases than in ASCUS/LGSIL (p = 0,038). Independently of cervical cytology, HPV 18 viral load was lower (7.93 x 10(4) copies/microL) than HPV 16 viral load (5 x 10(13)) copies/microL). CONCLUSIONS: For HPV types 16 or 18 positive patients with LGSIL cytology the viral load might have predictive value. Our study suggested that patients with elevated viral loads are at disease risk progression and should be carefully evaluated.

P16INK4A--A possible marker in HPV persistence screening.

UNLABELLED: The aim of this study was to investigate the correlation of p161NK4a expression levels with the cytological group of cervical carcinogenesis (NILM, ASCUS, LSIL, HSIL, cancer groups), in order to establish its value as potential diagnostic marker. METHODS: The smears obtained from 50 women with/without suggestive HPV infection pathology were subjected to cytological investigations. The viral testing was based on the detection of HPV DNA using the INNOLIPA kit, while the semiquantitative expression levels of p16INK4a were estimated by RT-PCR. RESULTS: p16INK4a expression level was correlated with the cytological degree of cervical lesions. In LSIL patients, p16INK4a values were 1.36 times greater than in NILM subjects (p = 0.07). In HSIL/cancer patients, p16INK4a values were 2.38 times greater than in NILM patients (p = 0.002). We also noticed significant differences between ASCUS: HSIL group (p = 0.02) and LSIL: HSIL (p = 0.07) group. The p16INK4a expression level was dependent of HPV genotype, p16INK4a mRNA presence being correlated with the presence of hrHPV in low and high risk lesions.

High-risk human papillomaviruses distribution in Romanian women with negative cytology.

INTRODUCTION: Romania has the highest incidence and mortality rate of cervical cancer in Europe. The objective was to estimate the prevalence of high-risk human papillomavirus (hrHPV) genotypes and to evaluate the role of certain socio-behavioral factors in acquiring viral infection, in a cohort of Romanian women with negative Pap. METHODOLOGY: In a prevalence study 611 women (aged 17-58 years) with negative Pap, with no known history of atypical cytology and valid HPV test were included. Each participant completed a questionnaire containing data on socio-behavioral factors. From 344 women aged between 30-58 years, 63 were randomly selected for a second examination (conventional cytology and HPV detection and genotyping) after twelve months. RESULTS: Of the 611 women, 19.80% were HPV positive, 14.73% infected with hrHPV. Differences in the prevalence of hrHPV (17.60% versus 12.50%) as single (13.01% vs 9.01%) and multiple infections (9.71% vs 3.49%) were noted between women under the age of 30 and above. Among socio-behavioral factors, marital status and multiple sexual partners correlate with HPV and hrHPV infection. At follow-up, from 34 HPV negative cases, 10 changed to positive (5 hrHPV), while 2 developed abnormal cytology. Out of the 29 HPV positive cases, 12 cleared the HPV infection and 17 retested positive of which 4 worsened their cytology. CONCLUSIONS: In Romania, HPV infection is common in women with negative cytology. HPV genotyping is of epidemiological importance because the distribution of hrHPV types can determine the impact of prophylactic vaccines and the necessity of HPV testing as screening method.

Methylation of tumour suppressor genes associated with thyroid cancer.

BACKGROUND: Thyroid carcinoma is the most common endocrine malignancy worldwide. Changes in DNA methylation can cause silencing of normally active genes, especially tumour suppressor genes (TSG) or activation of normally silent genes. OBJECTIVE: The aim of this study is to evaluate the degree of promoter methylation for a panel of markers for thyroid neoplasms and to establish their relationship with thyroid oncogenesis. METHODS: To generate a comprehensive DNA methylation signature of TSGs involved in thyroid neoplasia, we use Human TSG EpiTect Methyl II Signature PCR Array-Qiagen for 24 samples (follicular adenomas and papillary thyroid carcinomas) compared with normal thyroid tissue. We extended the evaluation for three TSGs (TP73, WIF1, PDLIM4) using qMS-PCR. Statistical analysis was performed with GraphPad Prism. RESULTS: We noted four important genes NEUROG1, ESR1, RUNX3, MLH1, which presented methylated promoter in tumour samples compared to normal. We found new characteristic of thyroid tumours: methylation of TP73, WIF1 and PDLIM4 TSGs, which can contribute to thyroid neoplasia. A significant correlation between BRAF V600E mutation and RET/PTC rearrangements with TIMP3 and CDH13, RARB methylation, respectively was observed. CONCLUSIONS: TSGs promoter hypermethylation is a hallmark of cancer and a test that uses methylation quantification method is suitable for diagnosis and prognosis of thyroid cancer.

Quantitative analysis of the relationship between microRNA­124a, -34b and -203 gene methylation and cervical oncogenesis.

Cervical cancer is a leading cause of mortality in women. Molecular and epidemiological data have unequivocally confirmed that high-risk human papillomaviruses (HPVs) are a major etiological agent of this malignancy, as host epigenetic alterations are induced in response to viral infection. The present study evaluated the methylation status of CpG islands surrounding miR-124a, miR-34b and miR-203 in 29 cervical cancer precursor lesions, 31 cervical tumors and 30 normal control samples, with the aim of identifying potential markers of cervical cancer. Direct quantitative methylation-specific PCR (qMSP) was used to evaluate the degree of methylation in the samples. HPV DNA was detected and genotyped using the Linear Array HPV Genotyping Test. Data were statistically analyzed using the Kruskal-Wallis test. Differences in miRNA hypermethylation between the tumor and control samples were highly significant for all the genes tested (p<0.0001). Significant results were also obtained regarding the hypermethylation of miR-124a and miR-203 in the precursor lesions compared to the control samples. Among the 29 patients with precursor lesions, 68.97% (20/29) presented high risk (hr)-HPV genotypes and 31.03% (9/29) were diagnosed with low risk (lr)-HPV. Significant results (p=0.0266) were obtained for miR-124a (hr-HPV group, mean 41.32; lr-HPV group, mean 6.74), revealing a strong association between the methylation process and the hr-HPV genotype. Borderline results (p=0.058) were obtained for miR-203 (hr-HPV group, mean 44.05; lr-HPV group, mean 3.33). These results confirm the involvement of epigenetic alterations in cervical oncogenesis. The lr-HPV precursor lesions had a methylation percent pattern similar to that of the normal samples, while the results for the hr-HPV precursor lesions and tumors indicate a possible involvement of the hr-HPV genotype in the miRNA methylation process.

Type-specific human papillomavirus detection in cervical smears in Romania.

Although Romania has one of the highest incidence of cervical cancer in Europe (30 new cases/100 000 women), little is known about the distribution of the human papillomaviruses (HPV) genotypes in this population. We seek to determine the distribution of HPV genotypes in women with normal and abnormal cervical cytology. We analyzed 460 cervical cytology specimens from women who self-referred to the gynecologic clinic. HPV was detected and genotyped using the commercially available INNOLiPA (INNOGENETICS NV) kit based on the reverse hybridization principle. HPV DNA was detected in 279 cases (60.7%) with a median age of 32.9 years. In HGSIL (High Grade Squamous Intraepithelial Lesion) cytology, the presence of HPV DNA was confirmed in 82.7% of cases. The most frequent high-risk genotype was HPV16, found in 32.6% of HPV-positive samples. The next common high-risk genotypes were HPV18, HPV31 and HPV51. Our findings on the distribution and frequency of the HPV genotypes in Romanian population confirmed the utility of the current available HPV vaccines, HPV16 and 18 being detected in 28.7% of cases in the investigated area.