Sherry Y. Wu

Antigen presentation potential is variable among human ovarian tumour and syngeneic murine models and dictates pre-clinical outcomes of immunotherapy

High grade serous ovarian carcinoma (HGSC) is a fatal gynaecological malignancy with limited therapeutic options. Immunotherapies targeting MHC-I-dependent antigen presentation offer potential. Currently, the antigen presentation machinery (APM) of widely used syngeneic murine HGSC models remains poorly characterised, limiting translational relevance. Here, we systematically evaluate APM gene expression in syngeneic murine and patient samples. Tap1 and Psmb8 were identified as critical APM markers, deficient in murine models and strongly correlating with MHC-I expression. Hierarchical clustering correlation analysis using these markers revealed that ID8-p53

Development of an innovative extracellular vesicle mimetic delivery platform for efficient miRNA delivery to tumours

Extracellular vesicles (EVs) display high degree of tissue tropism and therefore represent promising carriers for tissue-specific delivery of genes or drugs for the treatment of human diseases. However, current approaches for the loading of therapeutics into EVs have low entrapment efficiency and also do not adequately deplete endogenous EV content; thus, more effective approaches are needed. Here, we report an innovative EXtraCElluar vesicle surface Ligand-NanoParticles (EXCEL NPs), generated by transferring moieties of EVs onto the surface of synthetic nanoparticles. EXCEL NPs facilitate the efficient entrapment of therapeutics (89 % efficiency) and are completely devoid of pre-existing unwanted EV internal content. Importantly, we show that EXCEL NPs formulated using EVs derived from endothelial cells, astrocytes and macrophages retain the delivery characteristics of the original EVs. Using miRNA-146a as a model anti-cancer therapeutic, we further demonstrated successful delivery of miRNA-146a to IG10 orthotopic ovarian tumours in immune competent mice using EXCEL NPs formulated with macrophage-derived EVs. Our findings establish a new clinically translatable approach to leverage characteristics of endogenous EVs for therapeutic delivery. The versatility of the platform enables future application to different target cell types and therapeutic modalities.

Let-7i enhances anti-tumour immunity and suppresses ovarian tumour growth

AbstractCancer immunotherapy has seen significant success in the last decade for cancer management by enhancing endogenous cancer immunity. However, immunotherapies developed thus far have seen limited success in the majority of high-grade serous carcinoma (HGSC) ovarian cancer patients. This is largely due to the highly immunosuppressive tumour microenvironment of HGSC and late-stage identification. Thus, novel treatment interventions are needed to overcome this immunosuppression and complement existing immunotherapies. Here, we have identified through analysis of > 600 human HGSC tumours a critical role for Let-7i in modulating the tumoural immune network. Tumoural expression of Let-7i had high positive correlation with anti-cancer immune signatures in HGSC patients. Confirming this role, enforced Let-7i expression in murine HGSC tumours resulted in a significant decrease in tumour burden with a significant increase in tumour T cell numbers in tumours. In concert with the improved tumoural immunity, Let-7i treatment also significantly increased CD86 expression in antigen presenting cells (APCs) in the draining lymph nodes, indicating enhanced APC activity. Collectively, our findings highlight an important role of Let-7i in anti-tumour immunity and its potential use for inducing an anti-tumour effect in HGSC.