Small-molecule inhibitor HI-TOPK-032 improves NK-92MI cell infiltration into ovarian tumours

The effectiveness of natural killer (NK) cells transferred adoptively in combating solid tumours is limited by challenges such as their difficulty in penetrating tumours from the bloodstream and maintaining viability without the support of interleukin-2 (IL-2). Genetically modified NK-92MI cells, which can release IL-2 to sustain their viability, have been identified as a promising alternative. This adaptation addresses the negative consequences of systemic IL-2 administration. The role of PSD-95/discs large/ZO-1 (PDZ)-binding kinase (PBK) in cancer development is recognized, but its effects on immunity are not fully understood. This study explores how PBK expression influences the ability of NK-92MI cells to infiltrate ovarian tumours. Elevated levels of PBK expression have been found in various cancers, including ovarian cancer (OV), with analyses showing higher PBK mRNA levels in tumour tissues compared to normal ones. Immunohistochemistry has confirmed increased PBK expression in OV tissues. Investigations into PBK's role in immune regulation reveal its association with immune cell infiltration, indicating a potentially compromised immune environment in OV with high PBK expression. The small-molecule inhibitor HI-TOPK-032, which inhibits PBK, enhances the cytotoxicity of NK-92MI cells toward OV cells. It increases the production of interferon-γ and tumour necrosis factor-α, reduces apoptosis and encourages cell proliferation. Mechanistic studies showed that contact with OV cells treated with HI-TOPK-032 upregulates CD107a on NK-92 cells. In vivo studies demonstrated that HI-TOPK-032 improves the antitumour effects of NK-92MI cells in OVCAR3Luc xenografts, extending survival without significant side effects. Safety assessments in mice confirm HI-TOPK-032's favourable safety profile, highlighting its potential as a viable antitumour therapy. These results suggest that combining NK-92MI cells with HI-TOPK-032 enhances antitumour effectiveness against OV, indicating a promising, safe and effective treatment strategy that warrants further clinical investigation.

The prognostic significance of primary tumor site in vulvar cancer: a population-based cohort study

OBJECTIVE

To investigate the association of primary tumor site with prognosis in vulvar cancer, stratified by vulvar squamous cell carcinoma (SCC) and non-SCC histological types.

METHODS

This population-based retrospective study enrolled patients with vulvar cancer from the Surveillance, Epidemiology, and End Results database between January 2000 and December 2018. The primary outcome was cancer-specific survival (CSS). The prognostic difference between labium majus, labium minus and clitoris groups was investigated using Kaplan-Meier analyses and Cox proportional hazards regression analyses.

RESULTS

A total of 3,465 eligible patients with vulvar cancer were included with a mean age of 54.5 years. Among the 1,076 (31.1%) patients with non-SCC, the multivariate Cox regression analyses showed that labium minus-sited disease (hazard ratio [HR]=1.85; 95% confidence interval [CI]=1.27-2.71; p=0.001) and clitoris-sited disease (HR=2.37; 95% CI=1.47-3.85; p<0.001) were significantly associated with worse CSS, compared with labium majus-sited disease. However, among the 2,389 (68.9%) patients with SCC, no significant association of primary tumor site with CSS was found (p>0.05). Kaplan-Meier analyses also showed that the primary tumor site had a significant prognostic effect in vulvar non-SCC (p<0.001) but not in vulvar SCC (p=0.330).

CONCLUSION

Among vulvar non-SCC, patients with labium minus-sited disease had a significantly worse prognosis than those with labium majus-sited disease, and a significantly better prognosis than those with clitoris-sited disease. Gynecologic oncologists should consider the prognostic effect of primary tumor site in vulvar non-SCC, and make optimal, personalized treatment and surveillance strategies based on different primary tumor sites.