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Biology subjects

Fabrega, S.

Publications and source records attributed to Fabrega, S..

3 recordsLinked to original sources

Closed-loop sonothermogenetic control of CAR T cells for metronomic brain cancer therapy

Achieving durable CAR T cell responses against primary brain tumors and metastases requires strategies that enable intracranial control of therapy to overcome the barriers of solid tumor treatment without compromising safety. Here, we show that closed-loop sonothermogenetics enables remote regulation of CAR T cell therapeutic activity through the intact skull. Using MR-guided focused ultrasound with closed-loop temperature feedback, we modulate CAR T cells engineered with a genetically encoded thermal bioswitch to achieve metronomic activation in the brain without lasting adverse effects on healthy brain tissue. In murine models of brain cancer, metronomic production of NKG2D T cell engagers by intratumoral CAR T cells overcomes antigen heterogeneity in breast cancer brain metastasis and myeloid-derived immunosuppression in glioblastoma to drive antitumor responses. Our findings support the use of closed-loop sonothermogenetics for spatial and temporal control of CAR T cell therapies targeting solid brain tumors.

bioengineering↗

Abnormal autophagy is a critical mechanism in TANGO2-related rhabdomyolysis

Patients with pathogenic variants in the TANGO2 gene suffer from severe and recurrent rhabdomyolysis (RM) episodes precipitated by fasting. Since starvation promotes autophagy induction, we wondered whether TANGO2-related muscle symptoms result from autophagy insufficiency to meet cellular demands in stress conditions. Autophagy functioning was analyzed in vitro, in primary skeletal muscle cells from TANGO2 patients in basal and fasting conditions. In addition, we developed a tango2 morphant zebrafish model to assess the effect of tango2 knockdown (KD) on locomotor function and autophagy efficiency in vivo. We report that TANGO2 mutations are associated with decreased LC3-II levels upon starvation in primary muscle cells, but not in fibroblasts. In zebrafish larvae, tango2 knockdown induces locomotor defects characterized by reduced evoked movements which are exacerbated by exposure to atorvastatin, a compound known to cause RM. Importantly, RM features of tango2 KD are also associated with autophagy and mitophagy defects in zebrafish. Calpeptin treatment, a known activator of autophagy, is sufficient to rescue the locomotor properties, thanks to its beneficial effect on autophagy functioning in zebrafish and independently to its effect on calpain activity. LC3-II levels of primary muscle cells of TANGO2 patients are also improved by calpeptin treatment. Overall, we demonstrate that TANGO2 plays an important role in autophagy, and that autophagy efficiency is critical to prevent RM, thus giving rise to new therapeutic perspectives in the prevention of these life-threatening episodes in TANGO2 pathology.

cell biology↗

Human glioblastoma cell motility depends on the activity of the cysteine metabolism enzyme 3-Mercaptopyruvate sulfurtransferase

Cancer cells in similar functional states are found in all glioblastoma, despite the genomic heterogeneity observed between and within these brain tumors. Metabolism being downstream of all signaling pathways regulating cell behaviors, we looked for metabolic weaknesses in link with motility, a key functional state for glioblastoma aggressiveness. A signature-driven data reduction approach highlighted motile cells present in thirty tumors from four independent single-cell transcriptomic datasets. Analyses integrating trajectory modeling disclosed, as characteristic of motile cells, enhanced oxidative stress coupled with mobilization of the cysteine metabolism enzyme 3-Mercaptopyruvate sulfurtransferase (MPST). The soundness of this prediction was verified using migration and invasion assays with patient-derived cells and tissue organoids. Pharmacological and genetic manipulations showed that enhanced ROS production and MPST activity are required for the cells motility. Biochemical assays indicated that MPST acts by protecting protein cysteine residues from dismal hyperoxidation. In vivo, MPST knockdown translated in reduced tumor burden, and a robust increase in mice survival. These results show that enhanced oxidative stress coupled with MPST mobilization plays a key role in glioblastoma cell motility.

cancer biology↗