Genetic polymorphisms in the ITPKC gene and cervical squamous cell carcinoma risk

Cervical cancer is caused primarily by infection with oncogenic types of human papillomavirus (HPV). However, HPV infection alone is not sufficient for the progression to cervical cancer. Host immunogenetic factors may involve in the development of this disease. Inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) is recently shown to act as a negative regulator of T-cell activation. We aim to study if polymorphisms in the ITPKC gene are associated with the risk of cervical cancer in Taiwanese women. ITPKC rs28493229 C/G, rs890934 G/T, rs2303723 C/T, and rs10420685 A/G polymorphisms were genotyped in a hospital-based study of 465 women with cervical squamous cell carcinoma (CSCC) and 800 age-matched healthy control women. The presence and genotypes of HPV in CSCC were determined. The frequency of G/G genotype and G allele of the ITPKC rs28493229 polymorphism was significantly higher in patients with CSCC compared with controls (OR = 1.81, 95 % CI 1.20–2.73, P = 0.005, P _c = 0.02; OR = 1.70, 95 % CI 1.14–2.54, P = 0.008, P _c = 0.03, respectively). No significant associations were found for other 3 polymorphisms. Haplotype analysis revealed the distribution of haplotype CGTA was significantly reduced in women with CSCC (OR = 0.59, 95 % CI 0.40–0.89, P = 0.01, P _c = 0.04). In conclusion, we found the G/G genotype and G allele of the ITPKC rs28493229 polymorphism may contribute to the risk of CSCC in Taiwanese women. This finding provides new insights into the mechanisms of immune activation in cervical cancer.     

Chlamydia trachomatis infection and human papillomavirus in women with cervical neoplasia in Pernambuco-Brazil

Chlamydia trachomatis (CT) is the most common bacterial cause of sexually transmitted disease. High-risk human papillomavirus (HR-HPV) is considered the main etiological agent for cervical neoplasia. Evidences showed that the presence of co-infection of CT and HR-HPV plays a central role in the etiology of cervical intraepithelial neoplasia (CIN) and cervical cancer. The goals of this study were: evaluate the human papillomavirus (HPV) and CT prevalence among Brazilian women with abnormal cytology and provide the effect of this association on the severity of cervical neoplasia. The population of this study was composed by 142 women with incident histological incidence of CIN grades I, II, III or cervical cancer from Recife, Northeast of Brazil. The polymerase chain reaction method on a cervical brush specimen was used to detect both agents and the automatic sequencing method was used for HPV genotyping assay. The prevalence of HPV and CT was 100 and 24.65 %, respectively. Thirteen types of HPV were detected; HPV 16, 18, 31 and 33 were the most common. The most prevalent HPV types were HPV 16 and 18. A significant association between CT positive and HPV 16 infection was found (p < 0.0106; OR = 5.31; 95 % IC 1.59–17.67). In the study population, there was diversity of HPV infections, with high-risk types being the most common. Also, the data collected suggest that CT infection may play an important role in the natural history of HPV infection.     

High TMPRSS4 expression is a predictor of poor prognosis in cervical squamous cell carcinoma

Objective The aim of this study was to clarify the clinical role of TMPRSS4 expression in cervical squamous cell carcinoma (CSCC) and to investigate the role of TMPRSS4 in predicting outcomes of patients with CSCC. Methods The retrospective study enrolled 87 patients diagnosed with CSCC between 2004 and 2006. TMPRSS4 expression in CSCC was assessed by immunohistochemistry, and data on clinical variables were collected by retrospective chart review. The impact of TMPRSS4 expression on 5-year disease-free survival (DFS) and 5-year overall survival (OS) was assessed by Kaplan–Meier analysis and Cox proportional hazards modeling. Results The high expression of TMPRSS4 was 63.2% in 87 patients with CSCC, and 17.5% in 40 patients with benign cervical disease (P < 0.001). High TMPRSS4 expression was significantly associated with tumor grade (P = 0.005), lymph node metastasis (P = 0.004), and deep cervical stromal invasion (P = 0.025). Patients with high expression of TMPRSS4 had shorter OS and DFS than those with low expression (P = 0.0205 and P = 0.0318, respectively). In multivariate Cox regression analysis, high expression of TMPRSS4 was a potential prognostic indicator for OS (P = 0.041) and DFS (P = 0.015). Conclusion Our findings suggest that TMPRSS4 might play an important role in the progression of CSCC. TMPRSS4 could be a potential prognostic marker of CSCC.     

Activation of Wnt-β-catenin pathway in basal–parabasal layers of normal cervical epithelium comparable during development of uterine cervical carcinoma

In this study, importance of Wnt-β-catenin pathway in the development of uterine cervical carcinoma was evaluated. For this purpose, the profiles (expression/methylation/deletion) of β-catenin, p-β-catenin (Y654), Wnt3a, and APC were studied in disease free normal cervical epithelium (n = 9), adjacent normal cervical epithelium of primary tumors (n = 70), CIN (n = 28), CACX (n = 102) samples, and two CACX cell lines (HeLa and SiHa). Immunohistochemical analysis revealed high/medium (74–95%) expression of β-catenin/p-β-catenin (Y654) and Wnt3a and low expression (23–26%) of APC in proliferating basal–parabasal layers contrary to differentiated spinous layer in normal cervix irrespective of HPV16 infection. The expression profile of the genes in the basal–parabasal layers did not change significantly during development of CACX. High (66%) promoter methylation of APC was seen in basal–parabasal layers and the cervical lesions (42–69%), unlike in spinous layers (25%). The promoter methylation status of APC was validated by in vitro demethylation experiments using 5-aza-dC in CACX cell lines. However, additional deletion of APC was significantly increased from CIN (12%) to stage I/II (40%) and became comparable in stage III/IV (48%) of the tumor. Patients with alterations (deletion/methylation) of APC and high/medium expression of Wnt3a/β-catenin/p-β-catenin (Y654) showed significantly poor survival. Thus our data indicate that cumulative effect of Wnt3a overexpression and APC inactivation are needed for overexpression of β-catenin during the development of CACX.     

Genome-wide methylation profiling identifies hypermethylated biomarkers in high-grade cervical intraepithelial neoplasia

Epigenetic modifications, such as aberrant DNA promoter methylation, are frequently observed in cervical cancer. Identification of hypermethylated regions allowing discrimination between normal cervical epithelium and high-grade cervical intraepithelial neoplasia (CIN2/3), or worse, may improve current cervical cancer population-based screening programs. In this study, the DNA methylome of high-grade CIN lesions was studied using genome-wide DNA methylation screening to identify potential biomarkers for early diagnosis of cervical neoplasia. Methylated DNA Immunoprecipitation (MeDIP) combined with DNA microarray was used to compare DNA methylation profiles of epithelial cells derived from high-grade CIN lesions with normal cervical epithelium. Hypermethylated differentially methylated regions (DMRs) were identified. Validation of nine selected DMRs using BSP and MSP in cervical tissue revealed methylation in 63.2–94.7% high-grade CIN and in 59.3–100% cervical carcinomas. QMSP for the two most significant high-grade CIN-specific methylation markers was conducted exploring test performance in a large series of cervical scrapings. Frequency and relative level of methylation were significantly different between normal and cancer samples. Clinical validation of both markers in cervical scrapings from patients with an abnormal cervical smear confirmed that frequency and relative level of methylation were related with increasing severity of the underlying CIN lesion and that ROC analysis was discriminative. These markers represent the COL25A1 and KATNAL2 and their observed increased methylation upon progression could intimate the regulatory role in carcinogenesis. In conclusion, our newly identified hypermethylated DMRs represent specific DNA methylation patterns in high-grade CIN lesions and are candidate biomarkers for early detection.     

Differential MicroRNAs Expression in Serum of Patients with Lung Cancer, Pulmonary Tuberculosis, and Pneumonia

MicroRNAs (miRNAs) play critical regulatory roles in the physiological and pathological processes. The high stability of miRNAs in human serum represents attractive novel diagnostic biomarkers of clinical conditions. Several studies have shown that aberrant expression of miRNAs in human cancer including lung cancer, but little is known about their effects on some infectious lung diseases such as pulmonary tuberculosis (TB) and pneumonia. In this study, we investigated miRNA expression pattern in serum of Egyptian patients with lung cancer, TB, and pneumonia compared with matched healthy controls. Using microarray-based expression profiling followed by real-time quantitative polymerase chain reaction validation, we compared the levels of a series of circulating miRNAs (miR-21, miR-155, miR-182, and miR-197) in serum from patients with lung cancer (n = 65), pulmonary tuberculosis (n = 29), pneumonia (n = 29), and transudate (n = 16) compared with matched healthy controls (n = 37). MiRNA SNORD68 was the housekeeping endogenous control. We found that the serum levels of miR-21, miR-155, and miR-197 were significantly elevated in the patients with lung cancer and pneumonia whereas miR-182 and miR-197 levels were increased only in patients with lung cancer and TB, respectively, compared with controls. Receiver operating characteristic analysis revealed that miR-182, miR-155, and miR-197 have superior diagnostic potential in discriminating patients with lung cancer, pneumonia, and TB, respectively, from controls. Our results conclude that the differential expression of the four studied miRNAs can be potential non-invasive biomarkers for patients with lung cancer, TB and pneumonia.     

Alcohol Consumption and Viral Load Are Synergistically Associated with CIN1

Purpose

We investigated the association between alcohol consumption and risk of cervical intraepithelial neoplasia (CIN) and cervical cancer, and determined whether these associations were modified by human papillomavirus (HPV) viral load in high-risk HPV-positive women participating in the Korean HPV cohort study (KHPV).

Methods

Among the women recruited in the KHPV (n = 1,243) from March 2006 to December 2009, we analyzed normal cytology (n = 581) as control group, CIN1 (n = 299), CIN2/3 (n = 161), or cervical cancer (n = 202). Multinomial logistic analysis was performed to estimate multivariate-adjusted odds ratios (OR).

Results

Alcohol drinkers had an increased risk of CIN1 (OR = 2.18, 95% CI 1.22–3.89) compared with non-drinkers after adjusting for potential confounders. Subjects with more frequent alcohol consumption had a higher risk of CIN1 (p for linear trend <0.0001). Higher ethanol consumption was associated with an increased risk of CIN1 (p for linear trend = 0.0001). We also observed a synergistic effect between HPV viral load and alcohol consumption: drinkers with a high HPV viral load (≥100 RLU/PC) were associated with a significantly increased risk of CIN1 (OR = 19.1; 95% CI, 6.60–55.3, interaction p<0.001). There were no associations between alcohol drinking and CIN2/3 or cervical cancer.

Conclusions

HPV viral load and alcohol was associated with the risk of CIN1 among high-risk HPV-positive women. This is the first demonstration that alcohol is an independent and combined risk factor of CIN1.     

Host-cell DNA methylation patterns during high-risk HPV-induced carcinogenesis reveal a heterogeneous nature of cervical pre-cancer

Cervical cancer development following a persistent infection with high-risk human papillomavirus (hrHPV) is driven by additional host-cell changes, such as altered DNA methylation. In previous studies, we have identified 12 methylated host genes associated with cervical cancer and pre-cancer (CIN2/3). This study systematically analyzed the onset and DNA methylation pattern of these genes during hrHPV-induced carcinogenesis using a longitudinal in vitro model of hrHPV-transformed cell lines (n = 14) and hrHPV-positive cervical scrapings (n = 113) covering various stages of cervical carcinogenesis. DNA methylation analysis was performed by quantitative methylation-specific PCR (qMSP) and relative qMSP values were used to analyze the data. The majority of genes displayed a comparable DNA methylation pattern in both cell lines and clinical specimens. DNA methylation onset occurred at early or late immortal passage, and DNA methylation levels gradually increased towards tumorigenic cells. Subsequently, we defined a so-called cancer-like methylation-high pattern based on the DNA methylation levels observed in cervical scrapings from women with cervical cancer. This cancer-like methylation-high pattern was observed in 72% (38/53) of CIN3 and 55% (11/20) of CIN2, whereas it was virtually absent in hrHPV-positive controls (1/26). In conclusion, hrHPV-induced carcinogenesis is characterized by early onset of DNA methylation, typically occurring at the pre-tumorigenic stage and with highest DNA methylation levels at the cancer stage. Host-cell DNA methylation patterns in cervical scrapings from women with CIN2 and CIN3 are heterogeneous, with a subset displaying a cancer-like methylation-high pattern, suggestive for a higher cancer risk.     

Magic angle spinning NMR spectroscopic metabolic profiling of gall bladder tissues for differentiating malignant from benign disease

Gall bladder tissue specimens obtained from 112 patients were examined by high resolution magic angle spinning (HR-MAS) NMR spectroscopy. Fifty one metabolites were identified by combination of one and two-dimensional NMR spectra. To our knowledge, this is the first report on metabolic profiling of gall bladder tissues using HR-MAS NMR spectroscopy. Metabolic profiles were evaluated for differentiation between benign Chronic Cholecystitis (CC, n = 66) and xantho-granulomatous cholecystitis (XGC, n = 21) and malignant gall bladder cancer (GBC, n = 25). Increase in choline containing compounds, amino acids, taurine, nucleotides and lactate as common metabolites were observed in malignant tissues whereas lipid content was found low as compared to benign tissues. Principal component analysis obtained from the NMR data showed clear distinction between CC and GBC tissue specimens; however, 27 % of XGC tissues were classified with GBC. The partial least square discriminant analysis (PLS-DA) multivariate analysis between benign (CC, XGC) and malignant (GBC) on the training data set (CC; n = 51, XGC; n = 15, GBC; n = 19 tissues specimens) provided 100 % sensitivity and 94.12 % specificity. This PLS-DA model when executed on the spectra of unknown tissue specimens (CC; n = 15, XGC; n = 6, GBC; n = 6) classified them into the three histological categories with more than 95 % of diagnostic accuracy. Non-invasive in vivo MRS technique may be used in future to differentiate between benign (CC and XGC) and malignant (GBC) gall bladder diseases.     

Association of the Plasma and Tissue Riboflavin Levels with C20orf54 Expression in Cervical Lesions and Its Relationship to HPV16 Infection

Riboflavin deficiency can cause a variety of metabolic problems that lead to skin and mucosal disorders. Limited evidence suggests that high intake of riboflavin may reduce overall risks of cancer. However, association of this deficiency with cervical cancer and precancerous lesions are still not definitively known. In this study, we characterized the relationship between plasma and tissue riboflavin levels and C20orf54 protein expression in patients with cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma (CSCC) as well as the relationship of these levels with human papillomavirus virus 16, 18 (HPV16/18) infections. High-performance liquid chromatography (HPLC) was used to measure blood riboflavin levels in patients with CIN and CSCC, and an enzyme-linked immunosorbent assay (ELISA) was used to determine tissue riboflavin levels in patients with CSCC and matched normal mucous epithelia. The expression of C20orf54 in fresh CSCC and matched tissues were detected by qRT-PCR and western blot, respectively. And it was further confirmed by immunohistochemistry (IHC) with formalin-fixed, paraffin-embedded CIN and CSCC. An HPV genotyping chip was used to analyze HPV infection and typing. The results showed that patients with CIN and CSCC had decreased plasma riboflavin levels as compared with normal controls. There was also significantly decreased riboflavin in tissues from CSCC patients, when compared with normal cervical epithelia. C20orf54 expression were significantly up-regulated in CSCC compared to matched control on both mRNA and protein level. Tissue riboflavin levels were significantly lower in HPV16/18 positive tissue compared with HPV16/18-negative tissue, and an inverse association was found between tissue riboflavin levels and C20orf54 mRNA and protein expression in CSCC. Additionally, C20orf54 was significantly correlated with tumor stages. In conclusion, C20orf54 tend to play a protective role in Uyghur cervical carcinogenesis of which modulating riboflavin absorption, and it is also related with HPV infection.     

Methylomic analysis identifies frequent DNA methylation of zinc finger protein 582 (ZNF582) in cervical neoplasms

Background

Despite of the trend that the application of DNA methylation as a biomarker for cancer detection is promising, clinically applicable genes are few. Therefore, we looked for novel hypermethylated genes for cervical cancer screening.

Methods and Findings

At the discovery phase, we analyzed the methylation profiles of human cervical carcinomas and normal cervixes by methylated DNA immunoprecipitation coupled to promoter tiling arrays (MeDIP-on-chip). Methylation-specific PCR (MSP), quantitative MSP and bisulfite sequencing were used to verify the methylation status in cancer tissues and cervical scrapings from patients with different severities. Immunohistochemical staining of a cervical tissue microarray was used to confirm protein expression. We narrowed to three candidate genes: DBC1, PDE8B, and ZNF582; their methylation frequencies in tumors were 93%, 29%, and 100%, respectively. At the pre-validation phase, the methylation frequency of DBC1 and ZNF582 in cervical scraping correlated significantly with disease severity in an independent cohort (n = 330, both P<0.001). For the detection of cervical intraepithelial neoplasia 3 (CIN3) and worse, the area under the receiver operating characteristic curve (AUC) of ZNF582 was 0.82 (95% confidence interval  = 0.76–0.87).

Conclusions

Our study shows ZNF582 is frequently methylated in CIN3 and worse lesions, and it is demonstrated as a potential biomarker for the molecular screening of cervical cancer.     

Changes in type‐specific human papillomavirus load predict progression to cervical cancer

Persistent high-risk human papillomavirus (HPV) infection is strongly associated with the development of high-grade cervical intraepithelial neoplasia or cancer (CIN3+). However, HPV infection is common and usually transient. Viral load measured at a single time-point is a poor predictor of the natural history of HPV infection. The profile of viral load evolution over time could distinguish HPV infections with carcinogenic potential from infections that regress. A case-cohort natural history study was set-up using a Belgian laboratory database processing more than 100,000 liquid cytology specimens annually. All cytology leftovers were submitted to real-time PCR testing identifying E6/E7 genes of 17 HPV types, with viral load expressed as HPV copies/cell. Samples from untreated women who developed CIN3+ (n = 138) and women with transient HPV infection (n = 601) who contributed at least three viral load measurements were studied. Only single-type HPV infections were selected. The changes in viral load over time were assessed by the linear regression slope for the productive and/or clearing phase of infection in women developing CIN3+ and women with transient infection respectively. Transient HPV infections generated similar increasing (0.21 copies/cell/day) and decreasing (−0.28 copies/cell/day) viral load slopes. In HPV infections leading to CIN3+, the viral load increased almost linearly with a slope of 0.0028 copies/cell/day. Difference in slopes between transient infections and infections leading to CIN3+ was highly significant (P < .0001). Serial type-specific viral load measurements predict the natural history of HPV infections and could be used to triage women in HPV-based cervical cancer screening.     

Peripheral metabolic abnormalities of lipids and amino acids implicated in increased risk of suicidal behavior in major depressive disorder

Suicide is the most serious consequence of major depressive disorder (MDD), yet a vast majority of MDD patients never attempt nor commit suicide. This discrepancy suggests a predisposition to suicidal behavior independent of MDD. However, the molecular basis of this predisposition remains largely unknown, hampering development of specific and targeted treatment of MDD patients at risk for suicide. A proton nuclear magnetic resonance (¹H NMR)-based metabonomic approach was used to capture metabolic perturbations related to suicide predisposition in the context of MDD. ¹H NMR spectra of plasma sampled from drug-naïve depressed suicide attempters (n = 21), non-attempters (n = 35), and healthy controls (n = 35) were recorded and analyzed through a multivariate statistical approach. Multivariate statistical analysis demonstrated that the depressed suicide attempter group was significantly distinguishable from the depressed non-attempter group and controls group. Several key metabolites, including lipids (low-density lipoprotein, very low-density lipoprotein, cholesterol and unsaturated lipid), lipid metabolism-related molecules (glucose, pyruvate and lactate) and amino acids (alanine, glycine and taurine) responsible for discriminating depressed suicide attempters from the nonattempters and controls were identified. This study is the first to indicate that peripheral perturbations in lipid and amino acid metabolism may be implicated in the predisposition to suicide in MDD patients.     

Plasma proteome analysis of cervical intraepithelial neoplasia and cervical squamous cell carcinoma

Although cervical cancer is preventable with early detection, it remains the second most common malignancy among women. An understanding of how proteins change in their expression during a particular diseased state such as cervical cancer will contribute to an understanding of how the disease develops and progresses. Potentially, it may also lead to the ability to predict the occurrence of the disease. With this in mind, we aimed to identify differentially expressed proteins in the plasma of cervical cancer patients. Plasma from control, cervical intraepithelial neoplasia (CIN) grade 3 and squamous cell carcinoma (SCC) stage IV subjects was resolved by two-dimensional gel electrophoresis and the resulting proteome profiles compared. Differentially expressed protein spots were then identified by mass spectrometry. Eighteen proteins were found to be differentially expressed in the plasma of CIN 3 and SCC stage IV samples when compared with that of controls. Competitive ELISA further validated the expression of cytokeratin 19 and tetranectin. Functional analyses of these differentially expressed proteins will provide further insight into their potential role(s) in cervical cancer-specific monitoring and therapeutics.     

Metabolic profiling of cervical tubercular lymphadenitis tissues by proton HR-MAS NMR spectroscopy

Proton metabolic profiling of incisional biopsied cervical lymph node tissue specimens of 109 patients suffering from tubercular (CTBL) and non-specific (NSCLA) lymphadenitis were analyzed by high resolution magic angle spinning (HR-MAS) NMR spectroscopy. In the present study, 40 endogenous metabolites namely, myo-inositol (m-Ins), branched chain amino acids (BCAA), glutamate, serine, taurine (Tau) aromatic amino acids, choline (Cho) containing compounds and glucose were characterized. To the best of our knowledge, this is the first report on metabolic profiling of cervical tubercular lymph node tissues using HR-MAS NMR spectroscopy. The principal component analysis revealed a clear discrimination between CTBL and NSCLA tissues. Increase in the concentration of mobile poly unsaturated fatty acids, BCAA, Cho, Tau, glycine and a decrease in the concentration of lactate, phosphocholine and m-Ins was observed in CTBL cases. The partial least square discriminant analysis (PLS-DA) with R ² = 0.95 and Q ² = 0.92 provided >98 % of correct classification between the two groups. A PLS-DA training set model of 75 % (CTBL = 54, NSCLA = 27) of the subjects when subjected for prediction of 25 % cases (CTBL = 18, NSCLA = 10) as an unknown dataset provided more than 98 % of diagnostic accuracy in their respective histological categories. The receiver operator characteristic curve was generated from PLS-DA factor-1 projected an area under the curve of 0.962. The metabolic profile obtained from HR-MAS NMR spectroscopy may be used as surrogate markers in vivo MRS for differentiating between CTBL and NSCLA cases non-invasively.     

Plasma choline-containing phospholipids: potential biomarkers for colorectal cancer progression

Colorectal cancer (CRC) is believed to progress through the adenoma–carcinoma sequence. The adenoma–carcinoma transition is an important window for early detection and intervention of CRC. In the present study, plasma samples from patients with CRC (n = 120), patients with adenomatous polyps (AP) (n = 120), and healthy controls (n = 120) were collected. Plasma phospholipid levels were analyzed with liquid chromatography–tandem mass spectrometry. It was found that the plasma levels of major lysophosphatidylcholine (LPC) species were gradationally decreased from healthy controls, AP to CRC subjects. A formula including total saturated LPCs, 18:2 LPC and sphingosylphosphorylcholine (SPC) yielded a sensitivity and specificity of 88.3 and 80 % for separating CRC from healthy controls. An optimized model with total saturated LPCs, 20:4 LPC and sphingomyelins (SM) as markers yielded a sensitivity and specificity of 89 and 80 % for separating AP from the healthy controls. Moreover, with SM, SPC and saturated LPCs as markers, a model was made to separate CRC from AP with the sensitivity and specificity of 90 and 92.5 %, respectively. These data indicate that the plasma choline-containing phospholipid levels represent potential biomarkers to distinguish between healthy controls, AP and CRC cases, implying their clinical usage in CRC and/or AP-CRC progression detection.     

The overexpression of MCPH1 inhibits cell growth through regulating cell cycle-related proteins and activating cytochrome c-caspase 3 signaling in cervical cancer

MCPH1, initially identified as an hTERT repressor, has recently been implicated in mediating DNA damage response and maintaining chromosome integrity. This study is to investigate its potential role in the onset of cervical cancer. In the study, decreased expression of MCPH1 was observed in 19 of 31 cases (61.3 %) at mRNA level and 44 of 63 cases (69.8 %) at protein level of cervical tumor tissues compared with the paired nontumor tissues. Reduced MCPH1 protein expression was significantly associated with high-tumor grade (1 vs. 3 P = 0.013; 2 vs. 3 P = 0.047). In addition to inhibit SiHa cell migration and invasion, the overexpression of MCPH1 inhibited cervical cancer cells growth through inducing S phase arrest and mitochondrial apoptosis. Further analysis demonstrated cyclinA2/CDK2, CDC25C-cyclinB/CDC2, and p53/p21 pathways were involved in the MCPH1 overexpression-induced S phase arrest. Moreover, the overexpression of MCPH1 activated mitochondrial apoptosis through regulating several apoptosis-related proteins such as p53, Bcl-2, Bax, cytochrome c, caspase-3, and PARP-1. Our findings indicate that downregulated MCPH1 correlates with tumor progression in cervical cancer, and MCPH1 has an important role in regulating cell growth through regulating the cell cycle and apoptosis. Thus, it may be a crucial tumor suppressor gene and a novel candidate therapeutic target for cervical cancer.     

Genome-wide methylation profiling identifies hypermethylated biomarkers in high-grade cervical intraepithelial neoplasia

Epigenetic modifications, such as aberrant DNA promoter methylation, are frequently observed in cervical cancer. Identification of hypermethylated regions allowing discrimination between normal cervical epithelium and high-grade cervical intraepithelial neoplasia (CIN2/3), or worse, may improve current cervical cancer population-based screening programs. In this study, the DNA methylome of high-grade CIN lesions was studied using genome-wide DNA methylation screening to identify potential biomarkers for early diagnosis of cervical neoplasia. Methylated DNA Immunoprecipitation (MeDIP) combined with DNA microarray was used to compare DNA methylation profiles of epithelial cells derived from high-grade CIN lesions with normal cervical epithelium. Hypermethylated differentially methylated regions (DMRs) were identified. Validation of nine selected DMRs using BSP and MSP in cervical tissue revealed methylation in 63.2–94.7% high-grade CIN and in 59.3–100% cervical carcinomas. QMSP for the two most significant high-grade CIN-specific methylation markers was conducted exploring test performance in a large series of cervical scrapings. Frequency and relative level of methylation were significantly different between normal and cancer samples. Clinical validation of both markers in cervical scrapings from patients with an abnormal cervical smear confirmed that frequency and relative level of methylation were related with increasing severity of the underlying CIN lesion and that ROC analysis was discriminative. These markers represent the COL25A1 and KATNAL2 and their observed increased methylation upon progression could intimate the regulatory role in carcinogenesis. In conclusion, our newly identified hypermethylated DMRs represent specific DNA methylation patterns in high-grade CIN lesions and are candidate biomarkers for early detection.     

Single nucleotide polymorphisms in the PRDX3 and RPS19 and risk of HPV persistence and cervical precancer/cancer

Background

Host genetic factors might affect the risk of progression from infection with carcinogenic human papillomavirus (HPV), the etiologic agent for cervical cancer, to persistent HPV infection, and hence to cervical precancer and cancer.

Methodology/Principal Findings

We assessed 18,310 tag single nucleotide polymorphisms (SNPs) from 1113 genes in 416 cervical intraepithelial neoplasia 3 (CIN3)/cancer cases, 356 women with persistent carcinogenic HPV infection (median persistence of 25 months) and 425 randomly selected women (non-cases and non-HPV persistent) from the 10,049 women from the Guanacaste, Costa Rica HPV natural history cohort. For gene and SNP associations, we computed age-adjusted odds ratio and p-trend. Three comparisons were made: 1) association with CIN3/cancer (compared CIN3/cancer cases to random controls), 2) association with persistence (compared HPV persistence to random controls), and 3) progression (compared CIN3/cancers with HPV-persistent group). Regions statistically significantly associated with CIN3/cancer included genes for peroxiredoxin 3 PRDX3, and ribosomal protein S19 RPS19. The single most significant SNPs from each gene associated with CIN3/cancer were PRDX3 rs7082598 (P _trend<0.0001), and RPS19 rs2305809 (P _trend=0.0007), respectively. Both SNPs were also associated with progression.

Conclusions/Significance

These data suggest involvement of two genes, RSP19 and PRDX3, or other SNPs in linkage disequilibrium, with cervical cancer risk. Further investigation showed that they may be involved in both the persistence and progression transition stages. Our results require replication but, if true, suggest a role for ribosomal dysfunction, mitochondrial processes, and/or oxidative stress, or other unknown function of these genes in cervical carcinogenesis.     

Risk factors associated with human papillomavirus prevalence and cervical neoplasia among Cameroonian women

BackgroundThis study used community-based cervical cancer screening for high-risk human-papillomavirus (HPV) to determine demographic and lifestyle factors associated with HPV prevalence and cervical intraepithelial neoplasia grade 2 or worse (CIN2+).MethodsWomen (n = 838) aged 25–65 years were recruited in two sequential studies in Cameroon. Demographic and historical data were obtained from participants and specimens were self-collected for HPV-testing using real-time PCR. HPV-positive women underwent biopsy and endocervical curettage. Associations were determined using bivariate analysis and logistic regression.ResultsHPV and self-reported HIV prevalence were 39.0% and 9.2%, respectively. Eighteen (9.3%) CIN2+ lesions were found among HPV-positive women. Housewives had a higher risk of being HPV infected (OR = 1.60, p = 0.010). HIV co-infection (aOR = 3.44, p < 0.001) and hormonal contraception (aOR = 1.97, p = 0.007) were associated with increased HPV prevalence. HPV-positive women who used condoms during sexual intercourse were at lower risk of CIN2+ (aOR = 0.15, p = 0.029). CIN2–3 lesions were found in women younger than 50 years, with a median age of 36 years (31–44). HPV-16/18-positive women had a 4.65-fold increased risk of CIN2+ (p = 0.015).ConclusionsYoung, single women and housewives were at higher risk of HPV infection. Preventive strategies for cervical cancer in low-resource settings should target women aged 30–50 years for HPV screening, and should focus treatment and follow-up on HPV-16/18-positive women. Further studies are needed to clarify if other risk factors require attention.