Determining the HPV vaccine schedule for a HIV-infected population in sub Saharan Africa, a commentary

Human papillomavirus genotype distribution patterns in Zimbabwe; is the bivalent vaccine sufficient?

BACKGROUND

Vaccination against Human papillomavirus (HPV) is the primary preventative strategy that has been shown to reduce the burden of HPV related diseases. Zimbabwe introduced the bivalent vaccine (HPV 16/18) in the vaccination program targeting prepubescent girls in 2018. This review is an analysis of the distribution of HPV genotypes from various studies conducted in Zimbabwe to ascertain the effectiveness of the bivalent vaccine and make recommendations for future HPV vaccine choices.

SUMMARY

Zimbabwean studies have mostly reported on cervical HPV in the urban areas. The most frequent HPV genotypes from cervical sites were 16, 18, 33, 35, 45, 56 and 58. These were identified from samples with normal cytology, pre-cancer and invasive cervical cancer. The few studies that have been done in rural areas reported HPV 35 as the most frequent cervicovaginal genotype. From the anal region of individuals reporting for routine screening, HPV 16, 18, 35 52 and 58 were the most frequent. A study on genital warts identified HPV 6, 11, 16, 40, 51and 54. In a study on children with recurrent respiratory papillomatosis (RRP), HPV 6 and 11 were the most common and HPV 35 was also identified in these children. There is no available published data on HPV distribution in head and neck cancers in Zimbabwe.

KEY MESSAGES

Given that 83% of cervical cancers in Zimbabwe are caused by HPV 16/18, the bivalent vaccine could cover a significant proportion of HPV related cervical cancer. The current limitation of the bivalent vaccine is its failure to prevent benign lesions such as genital warts and RRP or all cervical cancer cases in Zimbabwe. For the prevention of most HPV related conditions, the nonavalent vaccine would be the most appropriate option for the Zimbabwean population. Currently there is no vaccine that includes HPV 35, yet this genotype was frequently identified in HPV related diseases. Vaccine developers may need to consider HPV 35 when manufacturing the next generation HPV vaccines. Furthermore, boys should also be included in HPV vaccination programs to improve herd immunity, as well as prevent RRP and HPV-related head and neck cancers.

Can chronoradiotherapy offer benefits to cervical cancer patients? A scoping review

The objective of this scoping review was to synthesize the available evidence and evaluate the effectiveness of chronoradiotherapy interventions in cervical cancer patients. This scoping review was performed by searching in the PubMed, Cochrane Library, Embase, Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), China National Knowledge Infrastructure (CNKI), Wanfang, Wenpu, and Chinese Biomedical Literature (CBM) databases. Databases were searched for studies published in English or Chinese from inception to 21 May 2021, and reference lists of relevant reports were scanned. Two investigators independently screened eligible studies in accordance with predetermined eligibility criteria and extracted data. The included studies were summarized and analyzed. Five studies including a total of 422 patients with cervical cancer were included in the scoping review; four studies were Chinese, and one was Indian. Main themes identified included the efficiency of chronoradiotherapy and relevant toxic and side effects, including diarrhea toxicity, hematologic toxicity, myelosuppression, gastrointestinal mucositis, and skin reactions. Administration of radiotherapy at different times of the day resulted in similar efficacy. However, the toxic side effects of morning radiotherapy (MR) and evening radiotherapy (ER) differed, with radiotherapy in the evening leading to more severe hematologic toxicity and myelosuppression. There were conflicting conclusions about gastrointestinal reactions with chronoradiotherapy, and further studies are needed. Radiation responses may be associated with circadian genes, through the influence of cell cycles and apoptosis.

HIV-1 exploits Hes-1 expression during pre-existing HPV-16 infection for cancer progression

High Risk Human Papilloma Viruses (HR-HPV) persistently infect women with Human Immunodeficiency Virus-1 (HIV-1). HPV-16 escapes immune surveillance in HIV-1 positive women receiving combined antiretroviral therapy (cART). HIV-1 Tat and HPV E6/E7 proteins exploit Notch signaling. Notch-1, a developmentally conserved protein, influences cell fate from birth to death. Notch-1 and its downstream targets, Hes-1 and Hey-1 contribute to invasive and aggressive cancers. Cervical cancer cells utilize Notch-1 and hyper-express CXCR4, a co-receptor of HIV-1. Accumulating evidence shows that HIV-1 affects cell cycle progression in pre-existing HPV infection. Additionally, Tat binds Notch-1 receptor for activation and influences cell proliferation. Oncogenic viruses may interfere or converge together to favor tumor growth. The molecular dialogue during HIV-1/HPV-16+ co-infections in the context of Notch-1 signaling has not been explored thus far. This in vitro study was designed with cell lines (HPV-ve C33A and HPV-16+ CaSki) which were transfected with plasmids (pLEGFPN1 encoding HIV-1 Tat and pNL4-3 encoding HIV-1 [full HIV-1 genome]). HIV-1 Tat and HIV-1 inhibited Notch-1expression, with differential effects on EGFR. Notch-1 inhibition nullified Cyclin D expression with p21 induction and increased G2-M cell population in CaSki cells. On the contrary, HIV-1 infection shuts down p21 expression through interaction of Notch-1 downstream genes Hes-1-EGFR and Cyclin D for G2-M arrest, DDR response and cancer progression. This work lays foundations for future research and interventions, and therefore is necessary. Our results describe for the first time how HIV-1 Tat cancers have an aggressive nature due to the interplay between Notch-1 and EGFR signaling. Notch-1 inhibitor, DAPT used in organ cancer treatment may help rescue HIV-1 induced cancers.

Graphical abstract

The illustration shows how HIV interacts with HPV-16 to induce Notch 1 suppression for cancer progression (Created with BioRender.com).

Supplementary Information

The online version contains supplementary material available at 10.1007/s13337-023-00809-y.

Cervical cancer prevention in countries with the highest HIV prevalence: a review of policies

INTRODUCTION

Cervical cancer (CC) is the leading cause of cancer-related death among women in sub-Saharan Africa. It occurs most frequently in women living with HIV (WLHIV) and is classified as an AIDS-defining illness. Recent World Health Organisation (WHO) recommendations provide guidance for CC prevention policies, with specifications for WLHIV. We systematically reviewed policies for CC prevention and control in sub-Saharan countries with the highest HIV prevalence.

METHODS

We included countries with an HIV prevalence ≥ 10% in 2018 and policies published between January 1st 2010 and March 31st 2022. We searched Medline via PubMed, the international cancer control partnership website and national governmental websites of included countries for relevant policy documents. The online document search was supplemented with expert consultation for each included country. We synthesised aspects defined in policies for HPV vaccination, sex education, condom use, tobacco control, male circumcision,cervical screening, diagnosis and treatment of cervical pre-cancerous lesions and cancer, monitoring mechanisms and cost of services to women while highlighting specificities for WLHIV.

RESULTS

We reviewed 33 policy documents from nine countries. All included countries had policies on CC prevention and control either as a standalone policy (77.8%), or as part of a cancer or non-communicable diseases policy (22.2%) or both (66.7%). Aspects of HPV vaccination were reported in 7 (77.8%) of the 9 countries. All countries (100%) planned to develop or review Information, Education and Communication (IEC) materials for CC prevention including condom use and tobacco control. Age at screening commencement and screening intervals for WLHIV varied across countries. The most common recommended screening and treatment methods were visual inspection with acetic acid (VIA) (88.9%), Pap smear (77.8%); cryotherapy (100%) and loop electrosurgical procedure (LEEP) (88.9%) respectively. Global indicators disaggregated by HIV status for monitoring CC programs were rarely reported. CC prevention and care policies included service costs at various stages in three countries (33.3%).

CONCLUSION

Considerable progress has been made in policy development for CC prevention and control in sub Saharan Africa. However, in countries with a high HIV burden, there is need to tailor these policies to respond to the specific needs of WLHIV. Countries may consider updating policies using the recent WHO guidelines for CC prevention, while adapting them to context realities.

Elimination of cervical cancer in Tanzania: Modelled analysis of elimination in the context of endemic HIV infection and active HIV control

The World Health Organisation (WHO) has launched a strategic initiative for cervical cancer (CC) elimination which involves scaling up three interventions: human papillomavirus (HPV) vaccination, twice-lifetime HPV-screening screening and pre-cancer/cancer treatment by 2030. CC is challenging to control in countries with endemic human immunodeficiency virus (HIV), as women living with HIV (WLHIV) are at elevated risk of HPV infection, persistence and progression. This analysis estimated the impact of the elimination interventions on CC incidence and mortality but additionally considered more intensive screening for WLHIV, using Tanzania as an example. A dynamic HIV/HPV model was used to simulate the elimination strategy for vaccination, screening and pre-cancer/cancer treatment, with 3-yearly HPV-screening in WLHIV starting at age 25 years, in the context of sustained HIV control in Tanzania from 2020 to 2119. Without vaccination or HPV screening, CC incidence rates per 100 000 women are predicted to fall from 58.0 in 2020 to 41.6 (range: 39.1-44.7) in 2119, due to existing HIV control. HPV vaccination and twice-lifetime HPV-screening for the general population and 3-yearly screening for WLHIV, would reduce CC incidence to 1.3 (range: 1.3-2.5) by 2119, with elimination (<4/100 000) in 2076 (range: 2076-2092). CC mortality rates per 100 000 women are predicted to reach 1.1 (range: 1.1-2.1) with further reductions contingent on increased CC treatment access. Vaccination and 3-yearly HPV-screening for WLHIV is predicted to achieve elimination in the subgroup of WLHIV potentially as early as 2061 (range: 2061-2078), with a 2119 CC incidence rate of 1.7 (range: 1.7-3.3). Scaling-up vaccination and HPV-screening will substantially reduce CC incidence in Tanzania, with elimination predicted within a century. Three-yearly HPV-screening and HPV vaccination, at high coverage rates, would facilitate CC elimination among WLHIV, and thus accelerate elimination in the overall population.

Primary Care Guidance for Persons With Human Immunodeficiency Virus: 2020 Update by the HIV Medicine Association of the Infectious Diseases Society of America

Advances in antiretroviral therapy (ART) have made it possible for persons with human immunodeficiency virus (HIV) to live a near expected life span, without progressing to AIDS or transmitting HIV to sexual partners or infants. There is, therefore, increasing emphasis on maintaining health throughout the life span. To receive optimal medical care and achieve desired outcomes, persons with HIV must be consistently engaged in care and able to access uninterrupted treatment, including ART. Comprehensive evidence-based HIV primary care guidance is, therefore, more important than ever. Creating a patient-centered, stigma-free care environment is essential for care engagement. Barriers to care must be decreased at the societal, health system, clinic, and individual levels. As the population ages and noncommunicable diseases arise, providing comprehensive healthcare for persons with HIV becomes increasingly complex, including management of multiple comorbidities and the associated challenges of polypharmacy, while not neglecting HIV-related health concerns. Clinicians must address issues specific to persons of childbearing potential, including care during preconception and pregnancy, and to children, adolescents, and transgender and gender-diverse individuals. This guidance from an expert panel of the HIV Medicine Association of the Infectious Diseases Society of America updates previous 2013 primary care guidelines.

Cervical Dysplasia, Infection, and Phylogeny of Human Papillomavirus in HIV-Infected and HIV-Uninfected Women at a Reproductive Health Clinic in Nairobi, Kenya

High risk human Papillomavirus (HPV) infections ultimately cause cervical cancer. Human Immunodeficiency Virus (HIV) infected women often present with multiple high-risk HPV infections and are thus at a higher risk of developing cervical cancer. However, information on the circulating high-risk HPV genotypes in Kenya in both HIV-infected and HIV-uninfected women is still scanty. This study is aimed at determining the phylogeny and the HPV genotypes in women with respect to their HIV status and at correlating this with cytology results. This study was carried out among women attending the Reproductive Health Clinic at Kenyatta National Hospital, a referral hospital in Nairobi, Kenya. A cross-sectional study recruited a total of 217 women aged 18 to 50 years. Paired blood and cervical samples were obtained from consenting participants. Blood was used for serological HIV screening while cervical smears were used for cytology followed by HPV DNA extraction, HPV DNA PCR amplification, and phylogenetic analysis. Out of 217 participants, 29 (13.4%) were HIV seropositive, while 68 (31.3%) were positive for HPV DNA. Eight (3.7%) of the participants had abnormal cervical cytology. High-risk HPV 16 was the most prevalent followed by HPV 81, 73, 35, and 52. One participant had cervical cancer, was HIV infected, and had multiple high-risk infections with HPV 26, 35, and 58. HPV 16, 6, and 81 had two variants each. HPV 16 in this study clustered with HPV from Iran and Africa. This study shows the circulation of other HPV 35, 52, 73, 81, 31, 51, 45, 58, and 26 in the Kenyan population that play important roles in cancer etiology but are not included in the HPV vaccine. Data from this study could inform vaccination strategies. Additionally, this data will be useful in future epidemiological studies of HPV in Nairobi as the introduction or development of new variants can be detected.

Investigation of Cervical Tumor Biopsies for Chromosomal Loss of Heterozygosity (LOH) and Microsatellite Instability (MSI) at the HLA II Locus in HIV-1/HPV Co-infected Women

Background: A subgroup of women who are co-infected with human immunodeficiency virus type 1 (HIV-1) and human papillomavirus (HPV) progress rapidly to cervical disease regardless of high CD4 counts. Chromosomal loss of heterozygosity (LOH) and microsatellite instability (MSI) are early frequent genetic alterations occurring in solid tumors. Loss of an allele or part of a chromosome can have multiple functional effects on immune response genes, oncogenes, DNA damage-repair genes, and tumor-suppressor genes. To characterize the genetic alterations that may influence rapid tumor progression in some HIV-1-positive women, the extent of LOH and MSI at the HLA II locus on chromosome 6p in cervical tumor biopsy DNA samples with regard to HIV-1/HPV co-infection in South African women was investigated.

Methods: A total of 164 women with cervical disease were recruited for this study, of which 74 were HIV-1-positive and 90 were HIV-1-seronegative. DNA from cervical tumors and matched buccal swabs were used for analyses. Six fluorescently-labeled oligonucleotide primer pairs in a multiplex PCR amplification were used to study LOH and MSI. Pearson chi-squared test for homogeneity of proportions using an exact p value, a two-proportion Z-score test, ROC curves and a logistic regression model were used for statistical analyses. All p-values were corrected for false discovery rate (FDR) using the Benjamini-Hochberg test and the adjusted p-values (q-values) were reported. All tests were significant when both p and q < 0.05.

Results: Tumor DNA from HIV-1/HPV co-infected women demonstrated a higher frequency of LOH/MSI at the HLA II locus on chromosome 6p21.21 than tumor DNA from HIV-1-seronegative women (D6S2447, 74.2 vs. 42.6%; p = 0.001, q = 0.003), D6S2881 at 6p21.31 (78.3 vs. 42.9%; p = 0.002, q = 0.004), D6S2666 at 6p21.32 (79 vs. 57.1%; p = 0.035, q = 0.052), and D6S2746, at 6p21.33 (64.3 vs. 29.4%; p < 0.001, q < 0.001), respectively.

Conclusions: HPV infection alone can induce LOH/MSI at the HLA II locus in cervical tumor DNA, whereas HIV-1 co-infection exacerbates it, suggesting that this may accelerate cervical disease progression in a subgroup of HIV-1-positive women.