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Biology subjects

Bonney, G. K.

Publications and source records attributed to Bonney, G. K..

3 recordsLinked to original sources

MMPs and NETs are detrimental in human CNS-tuberculosis and MMP inhibition in a mouse model improves survival

Despite anti-tuberculous treatment (ATT), central nervous system tuberculosis (CNS-TB) still cause permanent neurological deficits and death. To identify prognostic factors, we profiled a prospective cohort of tuberculous meningitis (TBM) and non-TBM patients. We determined significantly increased cerebrospinal fluid (CSF) matrix metalloproteinases (MMPs) and neutrophil extracellular traps (NETs) are up-regulated in TBM patients with neuroradiological abnormalities and poor outcomes. To dissect mechanisms, we created a CNS-TB murine model which show neutrophil-rich necrotizing pyogranulomas with MMP-9 and NETs colocalizing, resembling human CNS-TB. Spatial transcriptomic analysis of both human and murine CNS-TB demonstrates a highly-inflamed and neutrophil-rich microenvironment of inflammatory immune responses, extracellular matrix degradation and angiogenesis within CNS-TB granulomas. Murine CNS-TB treated with ATT and MMP inhibitors SB-3CT or doxycycline show significantly suppressed NETs with improved survival. MMP inhibition arms show attenuated inflammation and well-formed blood vessels within granulomas. Adjunctive doxycycline is highly promising to improve CNS-TB outcomes and survival.

pathology↗

Multi-region spatial transcriptome analysis reveals cellular networks and pathways associated with hepatocellular carcinoma recurrence

Hepatocellular carcinomas (HCC) are driven by various etiologies and molecular diversity at presentation. Patient prognosis post-surgery is generally dismal, and the majority respond poorly to adjuvant targeted and/or immuno-therapies. Tumours are an ecosystem comprised of organization and interaction between different cell types that may contribute to clinically significant outcomes, such as disease recurrence. To better understand this phenomenon, we leveraged on a local cohort of patients with or without recurrence to generate spatial transcriptome profiles from multiple sectors from each tumour. We identified widespread gene expression intra- and inter tumour heterogeneity observed across the tumour sectors. Our analysis also revealed the cell type enrichment and localization, and ligand-receptor interactions identify a specific subset of endothelial cell enriched in primary tumours of patients with recurrence. Altogether, this study describes the spatial gene expression landscape in HCC patients associated with disease recurrence.

cancer biology↗

Ultrasound-mediated mechanical forces selectively kill tumor cells

Ultrasound has been used to target tumors either through local heating or local nanobubbles but these methods damage surrounding normal cells in the target area. Recent studies show that tumor cells are susceptible to mechanical stresses and undergo calcium-dependent apoptosis under conditions that promote normal cell growth. Here we report that low-frequency ultrasound causes apoptosis of tumor cells by activating a calpain-dependent mitochondrial pathway that depends upon calcium entry through the mechanosensitive Piezo1 channels. This is a general property of all tumor cell lines tested so far irrespective of tissue origin. In animals, ultrasound irradiation causes tumor killing in the chick chorioallantoic membrane (CAM) model with relatively little damage to the chick embryos. Further, patient-derived pancreatic tumor organoids are killed by ultrasound treatment. Because low-level ultrasound causes apoptosis of tumor cells from many different tissues in different microenvironments, it may offer a safe non-invasive approach to augment tumor treatments.

cancer biology↗