REBACIN® inhibits E6/E7 oncogenes in clearance of human papillomavirus infection

Novel therapeutic strategies for targeting E6 and E7 oncoproteins in cervical cancer

Cervical cancer is the fourth most common cause of cancer-related mortality among women worldwide. The main aetiological factor for developing cervical cancer is the persistent infection of Human papillomavirus (HPV). The E6 and E7 oncoproteins produced by HPV mainly contribute to the carcinogenic process by inhibiting the function of tumour suppressor genes. The E6 protein causes degradation of p53 leading to impaired cellular stress response. In contrast, the E7 protein impairs the activity of retinoblastoma protein (pRb) resulting in continuous cell cycle propagation. Even though screening programmes and prophylactic vaccination have reduced the incidence of cervical cancer, the disease burden is still high, especially in low socioeconomic countries. Treatment of cervical cancer involves a multimodal strategy incorporating surgery, chemotherapy, and radiotherapy. Most of these management approaches use invasive techniques and are associated with adverse effects. Drug resistance is observed over time with chemotherapeutic agents. Hence there is a crucial need for developing novel targeted treatment strategies for cervical cancer. The E6 and E7 viral oncoproteins are continuously expressed in HPV infected cells making them ideal targets for developing therapies. Therapeutic DNA vaccines, gene therapy involving RNA interference technology, and CRISPR are currently under intensive study. These technologies represent a productive and promising approach for the future treatment of cervical cancer. Moreover, several new compounds demonstrate significant anti-cancer effects against cervical cancer. This review provides an updated account of therapeutic strategies currently under research targeting the E6 and E7 viral oncoproteins.

Effect of different interventions on the treatment of high-risk human papillomavirus infection: a systematic review and network meta-analysis

Background

Persistent infection with high-risk human papillomavirus (HR-HPV) can lead to cervical intraepithelial neoplasia and cancer. At present, there is no medication that specifically targets HR-HPV infection.

Objective

This study aimed to evaluate the effectiveness of different interventions in promoting HR-HPV regression using a MeSH meta-analysis method.

Methods

A search for randomized controlled trials (RCTs) reporting different interventions for the treatment of HR-HPV infection included PubMed, Web of Science, Embase and Cochrane Library from the inception of the databases to March 8, 2023. Two researchers independently screened the articles, extracted data, and evaluated the quality. The literature that met the inclusion criteria was selected, the quality and risk of bias of the included studies were assessed according to the Cochrane 5.1 manual, and NMA was performed using Stata 16.0. The area under the cumulative ranking probability graph (SUCRA) represented the probability that each treatment would be the best intervention.

Results

Nine studies involving 961 patients and 7 treatment options were included in the analysis. The results of the network meta-analysis indicated the following rank order in terms of promoting HR-HPV conversion: Anti-HPV biological dressing > vaginal gel > imiquimod > REBACIN® > interferon > probiotics > observation/placebo > Polyphenon E.

Conclusion

Anti-HPV biological dressing treatment was found to be significantly effective in promoting HR-HPV conversion. However, further validation of the findings is necessary due to the limited number and quality of studies included in the analysis.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023413917.

Genetic variability analysis of human papillomavirus 58: Novel sublineage identification and persistent infection association

This study aims to characterize the genetic variability of HPV58, identify novel lineages and sublineages, and explore the association between persistent/multiple HPV58 infections and genetic variation. In this study, samples from 124 women with HPV58 infection in Eastern China were collected and 81 isolates of E6 and L1 full-length genes were successfully amplified from 55 samples. We evaluated the diversity of genetic variants and performed correlation analyses between genetic variability and pathology, vaccination, multiple infections, and persistent infections. Among the E6 and L1 gene sequences collected, the dominant prevailing sublineages were A1 (46.2%) and A2 (23.1%). In addition, we found two potential novel sublineages denoted as the A4 and A5 sublineage. A total of 50 nucleotide substitutions, including 28 synonymous substitutions and 22 nonsynonymous substitutions, were observed in the E6 and L1 genes. Among them, variants with A388C/K93N substitutions in the E6 gene correlated with persistent infection (≥1 and ≥2 years) (p < 0.005), and C307T/C66C was associated with persistent infection (≥2 years) (p < 0.005). Notably, two mutations above were detected in the isolate from the patient with breakthrough vaccine infection. Our study found two novel sublineages and sites of genetic variability in multiple and persistent infection variants. In addition, we identified two mutational sites associated with persistent infection. This study provides new insight into the clinical characteristics of HPV 58 genetic variations and offers new ideas for research on next-generation vaccines in Eastern China.

Effectiveness and safety of REBACIN as a non-invasive intervention for persistent high-risk human papillomavirus infection: A real-world prospective multicenter cohort study

BACKGROUND

We previously reported that REBACIN effectively eliminates persistent high-risk human papillomavirus (hrHPV) infection. Here, we conducted a prospective multicenter cohort study to evaluate the safety and effectiveness of REBACIN, taking into account factors such as specific hrHPV subtype and patient's age.

METHODS

According to inclusion/exclusion criteria and participant willingness, 3252 patients were divided into REBACIN group while 249 patients into control group. Patients in REBACIN group received one course treatment of intravaginal administration of REBACIN while no treatment in control group. After drug withdrawal, participants in both groups were followed up.

RESULTS

The clearance rate of persistent hrHPV infection in REBACIN group was 60.64%, compared to 20.08% in control group. Specifically, the clearance rates for single-type infection of HPV16 or HPV18 were 70.62% and 69.23%, respectively, which was higher than that of HPV52 (59.04%) or HPV58 (62.64%). In addition, the single, double, and triple/triple+ infections had a clearance rate of 65.70%, 53.31%, and 38.30%, respectively. Moreover, 1635 patients under 40 years old had a clearance rate of 65.14%, while it was 55.08% for 1447 patients over 40 years old. No serious adverse effects were found.

CONCLUSION

This study confirmed that REBACIN can effectively and safely eliminate persistent hrHPV infection, which the clearance rate of HPV16/18 is higher than that of HPV52/58, the clearance rate of single-type infection is higher than that of multiple-type infections, and the clearance rate in young patients is higher than that in elder patients, providing a guidance for REBACIN application in clearing hrHPV persistent infection in real-world settings.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry Registration Number: ChiCTR1800015617 http://www.chictr.org.cn/showproj.aspx?proj=26529 Date of Registration: 2018-04-11.

Human papillomavirus associated cervical lesion: pathogenesis and therapeutic interventions

Human papillomavirus (HPV) is the most prevalent sexually transmitted virus globally. Persistent high-risk HPV infection can result in cervical precancerous lesions and cervical cancer, with 70% of cervical cancer cases associated with high-risk types HPV16 and 18. HPV infection imposes a significant financial and psychological burden. Therefore, studying methods to eradicate HPV infection and halt the progression of precancerous lesions remains crucial. This review comprehensively explores the mechanisms underlying HPV-related cervical lesions, including the viral life cycle, immune factors, epithelial cell malignant transformation, and host and environmental contributing factors. Additionally, we provide a comprehensive overview of treatment methods for HPV-related cervical precancerous lesions and cervical cancer. Our focus is on immunotherapy, encompassing HPV therapeutic vaccines, immune checkpoint inhibitors, and advanced adoptive T cell therapy. Furthermore, we summarize the commonly employed drugs and other nonsurgical treatments currently utilized in clinical practice for managing HPV infection and associated cervical lesions. Gene editing technology is currently undergoing clinical research and, although not yet employed officially in clinical treatment of cervical lesions, numerous preclinical studies have substantiated its efficacy. Therefore, it holds promise as a precise treatment strategy for HPV-related cervical lesions.

The significance of nonsurgical therapies for cervical infection of high-risk human papilloma virus: A systematic review and meta-analysis

OBJECTIVE

To assess whether nonsurgical therapies were related with clearance of cervical infection of high-risk human papilloma virus (hr-HPV) or regression of mild abnormal cytology related with hr-HPV.

METHODS

Until March 2023, we identified a total of 10 424 women with cervical infection of hr-HPV and 1966 women with mild abnormal cytology related with hr-HPV from 44 studies that met the inclusion criteria.

RESULTS

After systematically retrieving literature, we identified 2317 citations and 44 randomized controlled studies (RCT) were enrolled. Cumulative results suggested women with cervical infection of hr-HPV might benefit from nonsurgical therapies. Both the clearance of hr-HPV (OR: 3.83, I2  = 99%, p < 0.00001) and regression of mild abnormal cytology related with hr-HPV (OR: 3.12, I2  = 63%, p < 0.00001) were significantly higher than control group. Subgroup analysis stratified by systematic therapy, topical therapy, traditional Chinese medicines (TCMs), and presistent hr-HPV got consistent results. There was substantial heterogeneity between trials (I2  = 87% for clearance of hr-HPV and 63% for regression of cytology), sensitivity analysis was performed by excluding single study one by one, and found the cumulative results were stable and dependable. Both the funnel plots for clearance of hr-HPV and regression of abnormal cytology were asymmetrical, significant publication bias might exist.

CONCLUSION

Nonsurgical therapies might benefit women who had a cervical infection of hr-HPV with/without mild abnormal cytology related with hr-HPV. Both the clearance of hr-HPV and regression of abnormal cytology were significantly higher than control group. More studies with less heterogeneity were needed urgently to draw concrete conclusion.