ABSTRACT
BACKGROUND: For hepatocellular carcinoma (HCC), effective therapeutic approaches are lacking. As aberrant gene methylation is a major contributor to HCC development, demethylating drugs such as 5-azacytidine (5-Aza) have been proposed. As most 5-Aza mechanisms of action are unknown, we investigated its phenotypic/molecular effects. METHODS: 5-Aza effects were examined in the human HCC cell lines JHH-6/HuH-7 and in the rat cell-line N1-S1. We also employed a xenograft mouse model (HuH-7), a zebrafish model (JHH-6), and an orthotopic syngeneic rat model (N1-S1) of HCC. RESULTS: 5-Aza downregulated cell viability/growth/migration/adhesion by upregulating miR-139-5p, which in turn downregulated ROCK2/cyclin D1/E2F1 and increased p27kip1, resulting in G1/G0 cell accumulation. Moreover, a decrease in cyclin B1 and an increase in p27kip1 led to G2/M accumulation. Finally, we observed a decrease in MMP-2 levels, a stimulator of HCC cell migration. Aza effects were confirmed in the mouse model; in the zebrafish model, we also demonstrated the downregulation of tumor neo-angiogenesis, and in the orthotopic rat model, we observed impaired N1-S1 grafting in a healthy liver. CONCLUSION: We demonstrate for the first time that 5-Aza can impair HCC development via upregulation of miR-139-5p, which in turn impairs the ROCK2/cyclin D1/E2F1/cyclin B1 pro-proliferative pathway and the ROCK2/MMP-2 pro-migratory pathway. Thus, we provide novel information about 5-Aza mechanisms of action and deepen the knowledge about the crosstalk among ROCK2/cyclin D1/E2F1/cyclin B1/p27kip1/MMP-2 in HCC.
ABSTRACT
Background To overcome obstacles within the Slovenian organised cervical cancer screening programme, a randomised pilot study of human papillomavirus (HPV) self-sampling among non-attenders was performed, aiming to assess three different screening approaches. Participants and methods Non-attenders aged 30-64 years from two Slovenian regions were randomised to two HPV self-sampling groups-the opt-in (I1, n = 14.400) and the opt-out (I2, n = 9.556), with a control group (P, n = 2.600). Self-collected samples were analysed using the Hybrid Capture 2 assay. HPV-positive women were invited to a colposcopy. The overall and type-specific intention-to-screen response rates and histological outcomes with a positive predictive value (PPV) according to the women's age, the screening approach, the level of protection resulting from previous screening history, and the region of residence were assessed. Results Of the 26.556 women enrolled, 8.972 (33.8%) responded with self-sample for HPV testing and/or traditional cytology within one year of enrolment. Response rates were 37.7%, 34.0% and 18.4% (p < 0.050) for opt-out, opt-in and control groups. Cervical intraepithelial neoplasia (CIN)2+ was diagnosed in 3.9/1.000, 3.4/1.000, and 3.1/1.000 women (p > 0.050), respectively. PPV of the HPV self-sampling was 12.0% and 9.6% for CIN2+ and CIN3+. The highest PPV was obtained in non-attenders in screening programme for more than 10-years and concordant results of HPV testing with 40.8% for CIN2+ and 38.8% for CIN3+. Conclusions The results of our study show that a high response to HPV self-sampling can be achieved also in an opt-in approach, if women are encouraged to choose between self-sampling at home and screening with gynaecologist. In addition, clinically important risk difference for a high-grade cervical lesion exists in the case of a positive result of HPV testing on self-collected samples, depending on the length of the interval since last screening. Stratified management of these women should be strongly considered. Women who were not screened with cytology for at least 10 years should be referred to immediate colposcopy for histology verification instead to delayed re-testing.
