Human papillomavirus 16 infection alters the Toll-like receptors and downstream signaling cascade: A plausible early event in cervical squamous cell carcinoma development.

OBJECTIVE: Toll-like receptors constitute an important component of innate immune mechanism. HPV is a known etiological factor of cervical cancer and is known to interfere with the expression of TLRs and downstream signaling pathway. It remains poorly understood whether HPV modulates the expression of TLRs. Hence, understanding HPV mediated immune alterations might aid in identifying novel therapeutic targets. The aim was to study the relative gene expression of TLRs & downstream signaling pathway in cervical carcinoma. METHODS: Cervical squamous cell carcinoma (CSCC) and normal cervical tissues were obtained. Subsequent to HPV genotyping, mRNA expression profiling using PCR Array was performed. Protein expression of relevant genes with western blot was studied. Levels of cytokines in cervicovaginal washes were estimated using a Luminex multiplex platform. RESULTS: All cases of cervical cancer were HR-HPV positive and predominant subtype was HPV16 (71.1%). Significant TLR4 upregulation and TLR2,7 downregulation were observed in HR-HPV infected cervix. TLR4,7 demonstrated low expression in CSCC. Molecules from cancer allied pathways; RELA, AKT, CDKN2A, and MDM2 demonstrated upregulation in CSCC. Protein expression data corroborated with gene expression profile. A diminished level of Th1 cytokines TNF-α, IFN-É£, IL-17, and IL-12 was observed in CSCC. Significantly increased levels of IL-1ß, IL-6 and IL-2 were detected in HR-HPV infected cervix. Kaplan Meier curve demonstrated high TLR4 and low TLR7 expression was associated with poor prognosis. CONCLUSION: The study demonstrates the HPV mediated dampening of the innate immune response in CSCC and provides support for exploring potential TLR2, 7 agonists as an adjunct therapy in CSCC patients.

Prevalence of Human Papilloma Virus Infection in Young Primiparous Women During Postpartum Period: Study from a Tertiary Care Center in Northern India.

INTRODUCTION: Assessment of high-risk Human Papilloma Virus (HPV) prevalence is important for monitoring long-term decrease in cervical cancer after implementation of the prophylactic HPV vaccination. AIM: To determine the prevalence of high-risk HPV infection and cytological abnormalities in young primiparous women in the age group of 16-26years. MATERIALS AND METHODS: In this cross-sectional study, 214 primiparous women aged 16-26years were recruited from a public tertiary health care center postpartum clinic between June 2013 and May 2014. Cytological analysis was performed by Pap smear test and patients underwent sampling with cervical brushes for HPV-DNA detection and typing by a PCR-based assay for HPV types 16, 18, 33 and 45. RESULTS: High-risk HPV was detected in 41 (19.2%) women. HPV 16 was found to be most prevalent with 17 (7.9%) samples testing positive, followed by HPV 18 in nine (4.2%), HPV 45 in six (2.8%) and HPV 31 in four (1.8%) women. Five women tested positive for more than one HPV types. There were no cases of intraepithelial lesions or cervical cancer. One patient who had Atypical Cells of Undetermined Significance (ASCUS) on cytology tested negative for all four HPV genotypes. CONCLUSION: This study provides a geographic baseline data of high-risk HPV prevalence in young Indian women before implementation of a vaccination program. The results are important for comparison with other global regions and monitoring the effect of HPV vaccination.

Characterization of Toll-like receptor transcriptome in squamous cell carcinoma of cervix: A case-control study.

OBJECTIVE: Human papillomavirus (HPV) is a proven etiological agent for cervical cancer However, not all HPV infections result in cervical cancer. The mechanisms of host immune system to prevent/control HPV infection remain poorly understood. Toll-like receptors (TLRs) are a system of innate immune defense. HPV has been demonstrated to modulate TLR expression and interfere in TLR signaling pathways, leading to persistent viral infection and carcinogenesis. The aim was to study the relative gene expression of TLRs in cervical squamous cell carcinoma (SCC). METHODS: Gene expression profile of TLRs 1 to 9 was examined in 30 cervical SCCs and an equal number of normal cervical tissue samples using a PCR array platform. Gene expression studies for TLRs 3 and 7 were validated by western blotting. RESULTS: HPV was detected in all cases and in none of the controls (p<0.0001). HPV16 was the preponderant (83.3%) subtype. A significant downregulation in the relative gene expression of TLR3 (p<0.0001), TLR4 (p<0.0005) and TLR5 (p<0.0001) was observed in cases. A significant upregulation for TLR1 was observed (p=0.006). Although TLRs 2, 7, 8 and 9 were upregulated and TLR6 was downregulated, it was not significant. The western blot performed with antibodies against TLRs 3 and 7 confirmed the findings of the gene expression studies. CONCLUSIONS: A significant downregulation in the gene expression of TLRs 3, 4 and 5 and upregulation of TLR1 was observed in cervical SCC as compared to controls. Study results evoke the proposition for investigating TLRs 3, 4 and 5 agonists for therapeutic exploration.