Developing Oncolytic Viruses for the Treatment of Cervical Cancer

Cervical cancer represents one of the most important malignancies among women worldwide. Current therapeutic approaches for cervical cancer are reported not only to be inadequate for metastatic cervical cancer, but are also considered as cytotoxic for several patients leading to serious side effects, which can have negative implications on the quality of life of women. Therefore, there is an urgent need for the development of innovative and effective treatment options. Oncolytic viruses can eventually become effective biological agents, since they preferentially infect and kill cancer cells, while leaving the normal tissue unaffected. Moreover, they are also able to leverage the host immune system response to limit tumor growth. This review aims to systematically describe and discuss the different types of oncolytic viruses generated for targeting cervical cancer cells, as well as the outcome of the combination of virotherapy with conventional therapies. Although many preclinical studies have evaluated the therapeutic efficacy of oncolytic viruses in cervical cancer, the number of clinical trials so far is limited, while their oncolytic properties are currently being tested in clinical trials for the treatment of other malignancies.

p16/Ki-67 Dual Staining Is a Reliable Biomarker for Risk Stratification for Patients With Borderline/Mild Cytology in Cervical Cancer Screening

BACKGROUND/AIM

To evaluate p16/Ki-67 dual-staining performance for detection of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) in the management of women with minor cervical abnormalities.

PATIENTS AND METHODS

All 759 enrolled patients were tested for cytology, high-risk human papillomavirus (HR-HPV) and dual p16/Ki-67 staining.

RESULTS

Positivity rates for HR-HPV and dual staining increased as dysplasia was worsened from non-CIN (37.6% and 0%) to CIN1 (62.5% and 1.6%) and CIN2+ (98.7% and 97.3%), respectively. HPV18 and HPV16 exhibited the highest odds ratios (53.16 and 11.31) in the CIN2+ group. Both p16/Ki-67 dual staining and HR-HPV presented similar sensitivities (97.3% and 98.7%, respectively) for CIN2+ detection. Dual staining specificity, however, was 99.3%, significantly higher compared to HR-HPV testing (52.2%). The utility of dual staining was evaluated in different screening strategies and appeared to reduce the number of colposcopies required for the detection of CIN2+ cases.

CONCLUSION

p16/Ki-67 dual-staining cytology is a surrogate triage biomarker in cytology-based screening programs, with high performance for efficient risk stratification of women with mild cervical abnormalities.

Mimiviruses: Giant viruses with novel and intriguing features (Review)

The Mimivirus is a giant virus that infects amoebae and was long considered to be a bacterium due to its size. The viral particles are composed of a protein capsid of ~500 nm in diameter, which is enclosed in a polysaccharide layer in which ~120–140 nm long fibers are embedded, resulting in an overall diameter of 700 nm. The virus has a genome size of 1.2 Mb DNA, and surprisingly, replicates only in the cytoplasm of the infected cells without entering the nucleus, which is a unique characteristic among DNA viruses. Their existence is undeniable; however, as with any novel discovery, there is still uncertainty concerning their pathogenicity mechanisms in humans and the nature of the Mimivirus virophage resistance element system (MIMIVIRE), a term given to describe the immune network of the Mimivirus, which closely resembles the CRISPR-Cas system. The scope of the present review is to discuss the recent developments derived from structural and functional studies performed on the distinctive characteristics of the Mimivirus, and from studies concerning their putative clinical relevance in humans.