Prevalence of active infection by herpes simplex virus type 2 in patients with high-risk human papillomavirus infection: A cross-sectional study.

The aim is to determine the prevalence of active infection by herpes simplex virus type 2 (HSV-2) among Mexican women with high-risk human papillomavirus (HR-HPV) cervical infection, recruited from public gynecology and colposcopy services. In a cross-sectional study, HSV-2 antibodies, HSV-2 DNA, and HR-HPV DNA were quantified. Significant differences in HSV-2 seroprevalence and HSV-2 active infection rates were found between negative and positive HR-HPV cases. HSV-2 seroprevalence was 28.15% and 16.1% (P = .0001), while HSV-2 active infection rates were 6.83% and 0.62% (P = .001) for positive and negative HR-HPV groups, respectively. The risk of HSV-2 seropositivity was 1.7 times greater for HR-HPV-positive cases (P = .02). Similarly, HR-HPV-positive cases were nine times more likely to have an HSV-2 active infection than HR-HPV-negative cases (P = .03). High HSV-2/h-HPV coinfection rates were observed among women recruited from public gynecology and colposcopy services. The main factors related to an HSV-2 active infection are a history of risky sexual behavior and HR-HPV infection. The prevalence of HSV-2 active infection among positive HR-HPV subjects indicate that these infections constitute an important group of STIs in Mexico.

A prospective cohort study to evaluate immunosuppressive cytokines as predictors of viral persistence and progression to pre-malignant lesion in the cervix in women infected with HR-HPV: study protocol.

BACKGROUND: Cervical cancer (CC) is caused by a persistent infection of high-risk human papillomavirus (HR-HPV). While most HPV infections are transient, persistent HPV infections are a significant health problem in Mexico. With an estimated HPV prevalence of 10% among women in reproductive age, approximately 25% of these women present at least a positive result in triage test, which according to previous studies is expected to be confirmed as positive CIN-2/3. The immune system has a key role in the natural history of HPV infection; alterations in the cellular immune response are responsible for the failure to eliminate HPV. The objective of this project is to assess the prognostic value of detecting immune markers (IL-10, IL-4, TGFß1, IFNγ, IL-6, and TNFα), the expression of HPV-HR E6/E7 proteins, and the viral load at the cervical level with respect to the persistence or clearance of HR-HPV infection, and the regression or progression of a cervical premalignant lesion. METHODS: A dynamic cohort study is being conducted in women with colposcopic, cytological, and histopathological results negative for squamous intraepithelial lesion (SIL) in the cervix and a positive HPV test; the subjects will be followed-up for 5 years, period from which 3 years have already elapsed, with yearly studies (colposcopy, cytology, and histopathology diagnosis, along with molecular HPV test, quantification of viral load and of IL-10, IL-4, TGFß1, INFγ, IL-6, and TNFα levels, along with the expression of the HR-HPV E6/E7 proteins in the cervix as a viral marker. The outcome will be categorized as viral persistence or clearance; and as SIL persistence, progression, or regression. Binomial and/or multinomial regression models adjusted for potential confounders will be used, associating the relative risk of the outcome with the immune and viral markers evaluated. DISCUSSION: This research will generate knowledge about immune markers with predictive value for the persistence and clearance of HPV, which will improve the triage of positive HPV women and thus reduce the economic burden for the Mexican health system imposed by the management of high-grade SIL and CC cases, which are still detected in late stages.

Risk allelic load in Th2 and Th3 cytokines genes as biomarker of susceptibility to HPV-16 positive cervical cancer: a case control study.

BACKGROUND: Alterations in the host cellular immune response allow persistent infections with High-Risk Human Papillomavirus (HR-HPV) and development of premalignant cervical lesions and cervical cancer (CC). Variations of immunosuppressive cytokine levels in cervix are associated with the natural history of CC. To assess the potential role of genetic host immunity and cytokines serum levels in the risk of developing CC, we conducted a case-control study paired by age. METHODS: Peripheral blood samples from patients with CC (n = 200) and hospital controls (n = 200), were used to evaluate nine biallelic SNPs of six cytokine genes of the adaptive immune system by allelic discrimination and cytokines serum levels by ELISA. RESULTS: After analyzing the SNP association by multivariate logistic regression adjusted by age, CC history and smoking history, three Th2 cytokines (IL-4, IL-6 and IL-10) and one Th3 (TGFB1) cytokine were significantly associated with CC. Individuals with at least one copy of the following risk alleles: T of SNP (-590C > T IL-4), C of SNP (-573G > C IL-6), A of SNP (-592C > A IL-10), T of SNP (-819C > T IL-10) and T of SNP (-509C > T TGFB1), had an adjusted odds ratio (OR) of 2.08 (95 % CI 1.475-2.934, p = 0.0001), an OR of 1.70 (95 % CI 1.208-2.404, p = 0.002), an OR of 1.87 (95 % CI 1.332-2.630, p = 0.0001), an OR of 1.67 (95 % CI 1.192-2.353, p = 0.003) and an OR of 1.91 (95 % CI 1.354-2.701, p = 0.0001), respectively, for CC. The burden of carrying two or more of these risk alleles was found to have an additive effect on the risk of CC (p trend = 0.0001). Finally, the serum levels of Th2 and Th3 cytokines were higher in CC cases than the controls; whereas IFNG levels, a Th1 cytokine, were higher in controls than CC cases. CONCLUSION: The significant associations of five SNPs with CC indicate that these polymorphisms are potential candidates for predicting the risk of development of CC, representing a risk allelic load for CC and can be used as a biomarker of susceptibility to this disease.

Cervical cancer-associated promoter polymorphism affects akna expression levels.

Cervical cancer (CC) is responsible for >260,000 deaths worldwide each year. Efforts are being focused on identifying genetic susceptibility factors, especially in genes related to the immune response. Akna has been proposed to be one of them, but data regarding its functional role in the disease is scarce. Supporting the notion of akna as a CC susceptibility gene, we found two polymorphisms associated with squamous intraepithelial lesion (SIL) and CC; moreover, we identified an association between high akna expression levels and CC and SIL, but its direction differs in each disease stage. To show the potential existence of a cis-acting polymorphism, we assessed akna allelic expression imbalance for the alleles of the -1372C>A polymorphism. We found that, regardless of the study group, the number of transcripts derived from the A allele was significantly higher than those from the C allele. Our results support the hypothesis that akna is a CC susceptibility genetic factor and suggest that akna transcriptional regulation has a role in the disease. We anticipate our study to be a starting point for in vitro evaluation of akna transcriptional regulation and for the identification of transcription factors and cis-elements regulating AKNA function that are involved in carcinogenesis.

HPV 16 E2 protein induces apoptosis in human and murine HPV 16 transformed epithelial cells and has antitumoral effects in vivo.

OBJECTIVE: Our aims were to examine the ability of the human papillomaviruse (HPV) 16 E2 protein to induce apoptosis in a murine HPV-transformed cell line, and to evaluate its antitumor properties on HPV-associated tumors in vivo in immunocompetent mice. METHODS: HPV-transformed murine BMK-16/myc cells and human SiHa cells were transfected with the HPV 16 E2 gene to examine the effects of the E2 protein on cell growth and on the E6 and E7 oncogenes as well as DNA fragmentation and activation of the extrinsic pathway of apoptosis. Finally, to test the antitumor effect of the E2 protein on an experimental mouse tumor model, we generated a recombinant adenovirus expressing the E2 protein. RESULTS: The E2 protein inhibited the growth of SiHa and BMK-16/myc cell lines, and repressed the E6 and E7 oncogenes. Moreover, the E2 protein induced DNA fragmentation and apoptosis through activation of caspases 8 and 3 in BMK-16/myc cells. On the other hand, E2 also showed antitumor effects in vivo. CONCLUSIONS: Our findings indicate that E2 exerts pro-apoptotic activity in a murine HPV-transformed cell line as well as an antitumor effect in vivo.

[Regulation of the cell cycle and the development of cancer: therapeutic prospects]. / Regulación del ciclo celular y desarrollo de cáncer: perspectivas terapéuticas.

Several genetic alterations occur during the transformation process from normal to tumor cells, that involve the loss of fidelity of processes as replication, reparation, and segregation of the genomic material. Although normal cells have defense mechanisms against cancer progression, in tumor cells different escape pathways are activated leading to tumor progression. Recent advances have permitted cancer research to focus on the identification of some of its etiological factors. The knowledge of cell cycle reveals a precise mechanism achieved by the coordinated interactions and functions of cyclin-dependent kinases, control checkpoint, and repair pathways. Furthermore, it has been demonstrated that this coordinated function can be abrogated by specific genetic changes. These findings suggest that the molecular mechanisms responsible for cellular transformation may help to identify potential targets to improve cancer therapies.