The Role of p53 Gene in Cervical Carcinogenesis

COVID-19 can lead to rapid progression of cervical intraepithelial neoplasia by dysregulating the immune system: A hypothesis

COVID-19 is a multisystem disease and cause of a global pandemic. Lately, cases of disease progression of HPV-infected CIN under SARS-CoV-2 infection were reported giving rise to the hypothesis of direct virus-infection induced pro-carcinogenic effect of SARS-CoV-2. We herein present a case of rapid progression from HPV-induced CIN 2 to microinvasive carcinoma within three months under COVID-19 without direct virus infection. Histopathologic evaluation, Fluorescence-in-situ hybridization and qRT-PCR against SARS-CoV-2 RNA as well as gene expression analysis were performed from the available FFPE-tissue and accompanied by an analysis of white blood cell differential. No signs of direct SARS-CoV-2 infection or COVID-19 typical alterations of cervical tissue were found. As expected, p53 decreased in expression with progression of dysplasia, while APOBEC3A and VISTA showed a decrease in expression contrary to observations in dysplasia progression. PD-L1 was expressed consistently or increased slightly but did not show the expected strong induction of expression. DNMT1 showed an increase in expression in CIN III and a slight decrease in carcinoma, while DNMT3a is consistently expressed in CIN II and decreased in carcinoma. Blood tests after COVID-19 showed substantial reduction of lymphocytes, eosinophils, T-cells, and NK-cells. Our results hint at an indirect effect of COVID-19 on the cervical neoplasm. We conclude that the immune system might be preoccupied and exhausted by the concurring COVID-19 disease, leading to less immunological pressure on the HPV-infected cervical dysplasia enabling rapid disease progression. Further, indirect proangiogenic and proinflammatory micromilieu due to the multisystemic effects of COVID-19 might play an additional role.

Molecular Mechanisms of HIV Protease Inhibitors Against HPV-Associated Cervical Cancer: Restoration of TP53 Tumour Suppressor Activities

Cervical cancer is a Human Papilloma virus-related disease, which is on the rise in a number of countries, globally. Two essential oncogenes, E6 and E7, drive cell transformation and cancer development. These two oncoproteins target two of the most important tumour suppressors, p53 and pRB, for degradation through the ubiquitin ligase pathway, thus, blocking apoptosis activation and deregulation of cell cycle. This pathway can be exploited for anticancer therapeutic interventions, and Human Immunodeficiency Virus Protease Inhibitors (HIV-PIs) have attracted a lot of attention for this anticancer drug development. HIV-PIs have proven effective in treating HPV-positive cervical cancers and shown to restore impaired or deregulated p53 in HPV-associated cervical cancers by inhibiting the 26S proteasome. This review will evaluate the role players, such as HPV oncoproteins involved cervical cancer development and how they are targeted in HIV protease inhibitors-induced p53 restoration in cervical cancer. This review also covers the therapeutic potential of HIV protease inhibitors and molecular mechanisms behind the HIV protease inhibitors-induced p53-dependent anticancer activities against cervical cancer.

HIV-Associated Cancer Biomarkers: A Requirement for Early Diagnosis

Globally, HIV/AIDS and cancer are increasingly public health problems and continue to exist as comorbidities. The sub-Saharan African region has the largest number of HIV infections. Malignancies previously associated with HIV/AIDS, also known as the AIDS-defining cancers (ADCs) have been documented to decrease, while the non-AIDS defining cancer (NADCs) are on the rise. On the other hand, cancer is a highly heterogeneous disease and precision oncology as the most effective cancer therapy is gaining attraction. Among HIV-infected individuals, the increased risk for developing cancer is due to the immune system of the patient being suppressed, frequent coinfection with oncogenic viruses and an increase in risky behavior such as poor lifestyle. The core of personalised medicine for cancer depends on the discovery and the development of biomarkers. Biomarkers are specific and highly sensitive markers that reveal information that aid in leading to the diagnosis, prognosis and therapy of the disease. This review focuses mainly on the risk assessment, diagnostic, prognostic and therapeutic role of various cancer biomarkers in HIV-positive patients. A careful selection of sensitive and specific HIV-associated cancer biomarkers is required to identify patients at most risk of tumour development, thus improving the diagnosis and prognosis of the disease.

Mutational analysis of p53 gene in cervical cancer and useful polymorphic variants in exons 3 and 4

Background

Factors contributing to the pathogenesis and progression of cervical cancer include poor attitude to screening and health intervention, late presentation, among others. Mutations in p53 gene have been attributed to several cancer cases. The present study was designed to find relationships between the mutation patterns in p53 gene and cervical carcinoma staging. Such knowledge could contribute to early diagnosis of cervical cancer.

Results

From the sequence analysis of p53 gene fragment isolated by polymerase chain reactions (PCR), nineteen (19) polymorphic variants were identified. Missense mutations occurred in 47% of the samples, 32% were silent mutations, 16% were frameshift mutations and 5% nonsense mutations. Socio-biological characteristics of the study participants revealed that 60% have husbands with multiple sexual partners and that only 23.3% of the participants have ever had the Papanicolaou (Pap) smear test prior to diagnosis, whilst 20% were unaware of the screening test.

Conclusions

Increased severity of cervical carcinoma staging as revealed from the histopathological analysis was found to be associated with accumulation of higher levels of mutations in the p53 gene. Molecular analysis of p53 gene mutations may prove useful as a screening biomarker for cervical cancer.

Proteomics pinpoints alterations in grade I meningiomas of male versus female patients

Meningiomas are among the most common primary tumors of the central nervous system (CNS) and originate from the arachnoid or meningothelial cells of the meninges. Surgery is the first option of treatment, but depending on the location and invasion patterns, complete removal of the tumor is not always feasible. Reports indicate many differences in meningiomas from male versus female patients; for example, incidence is higher in females, whereas males usually develop the malignant and more aggressive type. With this as motivation, we used shotgun proteomics to compare the proteomic profile of grade I meningioma biopsies of male and female patients. Our results listed several differentially abundant proteins between the two groups; some examples are S100-A4 and proteins involved in RNA splicing events. For males, we identified enriched pathways for cell-matrix organization and for females, pathways related to RNA transporting and processing. We believe our findings contribute to the understanding of the molecular differences between grade I meningiomas of female and male patients.

Effects of DCK knockdown on proliferation, apoptosis and tumorigenicity in vivo of cervical cancer HeLa cells

The present study explored the effect that deoxycytidine kinase (DCK) knockdown had on proliferation, apoptosis and tumorigenicity in vivo of cervical cancer HeLa cells. Human cervical cancer HeLa cells that had received no prior treatment were selected from the HeLa group. The HeLa-negative control (NC) group consisted of cells that had undergone an empty vector treatment, and finally the HeLa-short hairpin RNA (shRNA) group included cells that were treated by means of shRNA-DCK expression. DCK expressions were evaluated by quantitative real-time polymerase chain reaction in addition to western blotting assays. Cell proliferation was estimated using the Cell Counting Kit-8 (CCK-8) assay and cell cycle progression. Cell apoptosis was determined by flow cytometry. BALB/c nude mice (n=24) were selected to establish transplanted tumor models, with gross tumor volume measured every 3 days. The results in vitro were as follows: compared with the HeLa group, the HeLa-shRNA group exhibited downregulation of DCK expression and inhibition of cell proliferation at 48, 72 and 96 h. Additionally, more cells in the HeLa-shRNA group were arrested in G0/G1 stage and less in S and G2/M stages, as well as in promotion of cell apoptosis. In vivo results are as follows: when comparing the HeLa and HeLa-NC groups, the gross tumor volume of the transplanted tumor in nude mice in the HeLa-shRNA group was found to have decreased in 13, 16, 19 and 22 days. Based on these findings, our study suggests that DCK knockdown facilitates apoptosis while inhibiting proliferation and tumorigenicity in vivo of cervical cancer HeLa cells.