A clinically compatible drug‐screening platform based on organotypic cultures identifies vulnerabilities to prevent and treat brain metastasis

Abstract

We report a medium-throughput drug-screening platform (METPlatform) based on organotypic cultures that allows to evaluate inhibitors against metastases growing in situ. By applying this approach to the unmet clinical need of brain metastasis, we identified several vulnerabilities. Among them, a blood-brain barrier permeable HSP90 inhibitor showed high potency against mouse and human brain metastases at clinically relevant stages of the disease, including a novel model of local relapse after neurosurgery. Furthermore, in situ proteomic analysis applied to metastases treated with the chaperone inhibitor uncovered a novel molecular program in brain metastasis, which includes biomarkers of poor prognosis and actionable mechanisms of resistance. Our work validates METPlatform as a potent resource for metastasis research integrating drug-screening and unbiased omic approaches that is compatible with human samples. Thus, this clinically relevant strategy is aimed to personalize the management of metastatic disease in the brain and elsewhere.

Updating cancer research with patient-focused networks

“…These efforts would provide regulated and open access to valuable biospecimens. More importantly, they will provide the unique opportunity to systematically perform drug-screening using PDOCs established from multiorgan metastases, as we have developed for those affecting the brain [ 4 ]. As cancer patients continue to die mainly due to disseminated disease, we consider that the development of such an approach is crucial to bring personalized medicine to metastatic disease and not only the primary tumor.…”

Advancements in melanoma cancer metastasis models

“…Brain slices have also been used to investigate the role of astrocytes in facilitating melanoma brain tropism and metastasis as well as to study the role of genes in the regulation of migration and invasion of melanoma cells (Doron et al, 2019; Hegerfeldt et al, 2002; Murry et al, 2006; Schwartz et al, 2016; Zhang et al, 2022). Organotypic tissue slices allow for the study of biomechanical properties of organs (e.g., stiffness or cell adhesion) and analysis of treatment responses in an intact organ environment (Doron et al, 2019; Holsken et al, 2006; Murry et al, 2006; Radke et al, 2017; Zhu et al, 2022). However, optimal culture conditions must be carefully evaluated as different organs have different structures, phenotypic functions, and nutrient availability.…”

“…NASCENTES MELO et al (Doron et al, 2019;Holsken et al, 2006;Murry et al, 2006;Radke et al, 2017;Zhu et al, 2022). However, optimal culture conditions must be carefully evaluated as different organs have different structures, phenotypic functions, and nutrient availability.…”

Protocol for optical clearing and imaging of fluorescently labeled ex vivo rat brain slices

“…For decades, they have been invaluable for electrophysiological studies, 1 , 2 , 3 modeling of neurodegenerative diseases, 4 , 5 and evaluation of therapeutic options prior to in vivo investigations. 6 However, microscopy strategies coupled with optical tissue clearing remain largely unexplored for brain slices even though deep tissue imaging with cellular resolution poses a major challenge in non-cleared tissue. 7 Here, we describe a detailed protocol for cutting, immunofluorescent labeling, and clearing to facilitate imaging of acute/cultured brain slices.…”