Molecular targets of HPV oncoproteins: potential biomarkers for cervical carcinogenesis.

Cervical cancer is the second most common cancer among women worldwide and is responsible for 275,000 deaths each year. Persistent infection with high-risk human papillomavirus (HR-HPV) is an essential factor for the development of cervical cancer. Although the process is not fully understood, molecular mechanisms caused by HPV infection are necessary for its development and reveal a large number of potential biomarkers for diagnosis and prognosis. These molecules are host genes and/or proteins, and cellular microRNAs involved in cell cycle regulation that result from disturbed expression of HR-HPV E5, E6 and E7 oncoproteins. One of the current challenges in medicine is to discover potent biomarkers that can correctly diagnose cervical premalignant lesions and standardize clinical management. Currently, studies are showing that some of these molecules are potential biomarkers of cervical carcinogenesis, and it is possible to carry out a more accurate diagnosis and provide more appropriate follow-up treatment for women with cervical dysplasia. In this paper, we review recent research studies on cell cycle molecules deregulated by HPV infections, as well as their potential use for cervical cancer screening.

Reduced Expression of IL-1ß and IL-18 Proinflammatory Interleukins Increases the Risk of Developing Cervical Cancer.

Background: The objective of this study was to analyze the gene expression profile of the proinflammatory interleukins, (IL-1ß and IL-18) in patients with premalignant lesions and cervical cancer. Methods: Total IL-1ß and IL-18 mRNA was quantified by qPCR to obtain the expression data in cervical tissues. A total of 74 cervical biopsies were obtained from women undergoing a colposcopy. The samples were divided into: normal (19), low level lesions (LSIL) or NIC I (17), high level lesions (HSIL) or CIN II and CIN III (29) and cancer (9). The normal cervical tissue samples were included as controls. The OR and 95% CI were calculated for the determination of the risk of progression between each type of lesion and cancer using logistic regression. Results: The results showed that an increase in the risk of progression of pre-neoplastic lesions to cancer was between 2.5 and 2.08 times higher in women with lower IL-1ß and IL-18 expression, respectively. Conclusions: This study provided evidence that IL-1ß and IL-18 are potential biomarkers that can be explored in further studies for monitoring the evolution of pre-neoplastic lesions and avoiding overtreatment or undertreatment of the patients.

Quantifying mRNA and microRNA with qPCR in cervical carcinogenesis: a validation of reference genes to ensure accurate data.

A number of recent studies have catalogued global gene expression patterns in a panel of normal, tumoral cervical tissues so that potential biomarkers can be identified. The qPCR has been one of the most widely used technologies for detecting these potential biomarkers. However, few studies have investigated a correct strategy for the normalization of data in qPCR assays for cervical tissues. The aim of this study was to validate reference genes in cervical tissues to ensure accurate quantification of mRNA and miRNA levels in cervical carcinogenesis. For this purpose, some issues for obtaining reliable qPCR data were evaluated such as the following: geNorm analysis with a set of samples which meet all of the cervical tissue conditions (Normal + CIN1 + CIN2 + CIN3 + Cancer); the use of individual Ct values versus pooled Ct values; and the use of a single (or multiple) reference genes to quantify mRNA and miRNA expression levels. Two different data sets were put on the geNorm to assess the expression stability of the candidate reference genes: the first dataset comprised the quantities of the individual Ct values; and the second dataset comprised the quantities of the pooled Ct values. Moreover, in this study, all the candidate reference genes were analyzed as a single "normalizer". The normalization strategies were assessed by measuring p16INK4a and miR-203 transcripts in qPCR assays. We found that the use of pooled Ct values, can lead to a misinterpretation of the results, which suggests that the maintenance of inter-individual variability is a key factor in ensuring the reliability of the qPCR data. In addition, it should be stressed that a proper validation of the suitability of the reference genes is required for each experimental setting, since the indiscriminate use of a reference gene can also lead to discrepant results.

Proteínas do plasma seminal de caprinos relacionadas com o índice pluviométrico e a qualidade do sêmen / Proteins of goat seminal plasma related with precipitation index and semen quality

O objetivo deste estudo foi identificar as proteínas do plasma seminal de caprinos da raça Alpina Americana criados na região Nordeste do Brasil que estão relacionadas ao índice pluviométrico e à qualidade do sêmen. O sêmen foi obtido pelo método de vagina artificial a partir de três reprodutores e foi avaliado quanto aos parâmetros macroscópicos e microscópicos. O perfil de proteínas do plasma seminal foi realizado por eletroforese bidimensional. Os parâmetros volume do sêmen, integridade do acrossoma e proteínas totais evidenciaram diferença significativa (P<0,05) entre os períodos de alto (1,7mL, 90,3% e 372μg mL-1,respectivamente) e baixo (1,2mL, 80,3% e 494μg mL-1, respectivamente) índice pluviométrico. Foram detectados, nos períodos de alto e baixo índice pluviométrico, 47 e 49 spots de proteínas com massa molecular relativa de 4 a 106kDa e de 15 a 97kDa e ponto isoelétrico de 3,00 a 8,96 e de 4,48 a 9,83, respectivamente. Apenas no período de alto índice pluviométrico foram observados os grupo de proteínas de 13kDa e 45kDa. Conclui-se que o sêmen de caprinos da raça Alpina Americana criados na região Nordeste do Brasil apresenta-se com melhor qualidade quando colhido no período de alto índice pluviométrico, o que pode ser atribuído à presença das proteínas de 13kDa e 45kDa.

The aim of this study was to identify proteins in seminal plasma of goats raised in the Northeast of Brazil relatedwith precipitation index and semen quality. Semen was obtained from three bucks and evaluated to the microscopic and macroscopic parameters. The profile of seminal plasma proteins was performed by analysis of two-dimensional electrophoresis. Volume, acrosome integrity and total proteins had significant difference (P<0.05) between the periods of high (1.7mL, 90.3% and 372g mL-1, respectively) and low (1.2mL, 80.3% and 494μgmL-1, respectively) precipitation index. It was detected during high and low precipitation index, 47 and 49 spots of proteins with molecular weight of 4 to 106kDa and 15 to 97kDa, and isoelectric point of 3.00 to 8.96, and 4.48 to 9.83, respectively. Only in the period of high precipitation index were observed groups of proteins with 13kDa and 45kDa. It can be concluded that semen of Alpine American goats raised in the Northeast of Brazil has best quality when obtained in the period of high precipitation index, which can be attributed to the presence of protein with 13kDa and 45kDa.