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Weston, W.

Publications and source records attributed to Weston, W..

3 recordsLinked to original sources

PDGFRα-directed fibroblast-homing peptides for targeted delivery of nucleic acid therapeutics

Efficient and cell type-specific delivery remains a major barrier to the clinical translation of nucleic acid therapeutics (NATs), particularly for fibroblast-driven diseases in which target cells are poorly accessible in vivo. By integrating single-cell transcriptomics with cell-surface protein profiling, we identified platelet-derived growth factor receptor alpha (PDGFR) as a fibroblast-enriched surface receptor. A panel of PDGFA-derived short peptides was designed and screened across multiple human and mouse cell types, leading to the identification of two fibroblast-homing peptides, Pep3 and Pep5, which displayed rapid and preferential uptake in fibroblasts. PDGFR; knockdown reduced peptide internalisation as measured by live-cell imaging, confirming receptor-mediated uptake. To evaluate their potential as delivery vehicles for NATs, a fibroblast-based cellular model of collagen VI-related congenital muscular dystrophy (COL6-CMD) was used for further validation. Lead peptides were conjugated to a splice-switching phosphorodiamidate morpholino oligomer (PMO) targeting the recurrent COL6A1 c.930+189C>T variant. Peptide-PMO conjugates retained exon-skipping activity and Pep3-PMO enhanced collagen VI protein deposition in patient-derived fibroblasts following repeated treatment compared to unconjugated PMO. Transcriptomic profiling demonstrated no activation of inflammatory, oncogenic, or PDGFR; receptor-associated signalling pathways following peptide-PMO treatment. Collectively, these findings establish PDGFR-targeting fibroblast-peptides as a promising platform for selective delivery of NATs to fibroblasts.

molecular biology↗

HER2 overexpression initiates breast tumorigenesis non-cell-autonomously by inducing oxidative stress in the tissue microenvironment

HER2 is considered as a driver oncogene responsible for the HER2+ subtype of breast cancer. However, it is still unclear how HER2 induces the oncogenic transformation of breast cancer stem cells (BCSCs) and initiates tumorigenesis during premalignant stage breast cancer. Here, we used clinical samples and mouse models of HER2+ breast cancer to demonstrate that neither BCSCs nor their cell-of-origin express HER2/Neu in early-stage breast tumors. Instead, our results demonstrate that Neu overexpression results in the transformation of BCSCs in a non-cell-autonomous manner via triggering DNA damage and somatic mutagenesis in their Neu-negative cell-of-origin. This is caused by the increased oxidative stress in the tissue microenvironment generated by altered energy metabolism and increased reactive oxygen species levels in Neu-overexpressing mammary ducts. Therefore, our findings illustrate a previously unrecognized mechanism of HER2-induced breast tumor initiation in vivo with potential impacts on future preventive treatments for HER2+ premalignant breast cancer.

cancer biology↗

Brilacidin, a COVID-19 Drug Candidate, Exhibits Potent In Vitro Antiviral Activity Against SARS-CoV-2

SummarySevere Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the newly emergent causative agent of coronavirus disease-19 (COVID-19), has resulted in more than one million deaths worldwide since it was first detected in 2019. There is a critical global need for therapeutic intervention strategies that can be deployed to safely treat COVID-19 disease and reduce associated morbidity and mortality. Increasing evidence shows that both natural and synthetic antimicrobial peptides (AMPs), also referred to as Host Defense Proteins/Peptides (HDPs), can inhibit SARS-CoV-2, paving the way for the potential clinical use of these molecules as therapeutic options. In this manuscript, we describe the potent antiviral activity exerted by brilacidin--a de novo designed synthetic small molecule that captures the biological properties of HDPs--on SARS-CoV-2 in a human lung cell line (Calu-3) and a monkey cell line (Vero). These data suggest that SARS-CoV-2 inhibition in these cell culture models is primarily a result of the impact of brilacidin on viral entry and its disruption of viral integrity. Brilacidin has demonstrated synergistic antiviral activity when combined with remdesivir. Collectively, our data demonstrate that brilacidin exerts potent inhibition of SARS-CoV-2 and thus supports brilacidin as a promising COVID-19 drug candidate. HighlightsO_LIBrilacidin potently inhibits SARS-CoV-2 in an ACE2 positive human lung cell line. C_LIO_LIBrilacidin achieved a high Selectivity Index of 426 (CC50=241M/IC50=0.565M). C_LIO_LIBrilacidins main mechanism appears to disrupt viral integrity and impact viral entry. C_LIO_LIBrilacidin and remdesivir exhibit excellent synergistic activity against SARS-CoV-2. C_LI Significance StatementSARS-CoV-2, the emergent novel coronavirus, has led to the current global COVID-19 pandemic, characterized by extreme contagiousness and high mortality rates. There is an urgent need for effective therapeutic strategies to safely and effectively treat SARS-CoV-2 infection. We demonstrate that brilacidin, a synthetic small molecule with peptide-like properties, is capable of exerting potent in vitro antiviral activity against SARS-CoV-2, both as a standalone treatment and in combination with remdesivir, which is currently the only FDA-approved drug for the treatment of COVID-19.

microbiology↗