Biology subjects

Escors, D.

Publications and source records attributed to Escors, D..

5 recordsLinked to original sources

bioRxiv2022

Metabolic dyshomeostasis induced by SARS-CoV-2 structural proteins reveals immunological insights into viral olfactory interactions

One of the most common symptoms in COVID-19 is a sudden loss of smell. SARS-CoV-2 has been detected in the olfactory bulb (OB) from animal models and sporadically in COVID-19 patients. To decipher the specific role over the SARS-CoV-2 proteome at olfactory level, we characterized the in-depth molecular imbalance induced by the expression of GFP-tagged SARS-CoV-2 structural proteins (M, N, E, S) on mouse OB cells. Transcriptomic and proteomic trajectories uncovered a widespread metabolic remodeling commonly converging in extracellular matrix organization, lipid metabolism and signaling by receptor tyrosine kinases. The molecular singularities and specific interactome expression modules were also characterized for each viral structural factor. The intracellular molecular imbalance induced by each SARS-CoV-2 structural protein was accompanied by differential activation dynamics in survival and immunological routes in parallel with a differentiated secretion profile of chemokines in OB cells. Machine learning through a proteotranscriptomic data integration uncovered TGF-beta signaling as a confluent activation node by the SARS-CoV-2 structural proteome. Taken together, these data provide important avenues for understanding the multifunctional immunomodulatory properties of SARS-CoV-2 M, N, S and E proteins beyond their intrinsic role in virion formation, deciphering mechanistic clues to the olfactory inflammation observed in COVID-19 patients.

systems biology↗

bioRxiv2020

HUMAN PANCREATIC CANCER CELLS UNDERGO PROFOUND METABOLIC REPROGRAMMING TOWARDS CELLULAR STEMNESS AS ADAPTATION TO INHIBITION OF THE AKT PATHWAY

Cancer cells acquire resistance to cytotoxic therapies targeting major survival pathways by adapting their metabolism. The AKT pathway is a major regulator of human pancreatic adenocarcinoma progression. The mechanisms of adaptation to long-term silencing of AKT isoforms of pancreatic cancer cells were studied. Following silencing, cancer cells remained quiescent for long periods of time, after which they recovered proliferative capacities. Adaptation caused profound proteomic changes largely affecting mitochondrial biogenesis, energy metabolism, and acquisition of a number of distinct cancer stem cell (CSC) characteristics depending on the AKT isoform that was silenced. The adaptation to AKT1 silencing drove most de-differentiation and acquisition of stemness through C-MYC down-modulation and NANOG up-regulation, which were required for survival of adapted CSCs. The changes associated to adaptation sensitized cancer cells to inhibitors targeting regulators of oxidative respiration and mitochondrial biogenesis. In vivo pharmacological co-inhibition of AKT and mitochondrial metabolism effectively controlled pancreatic adenocarcinoma growth in pre-clinical models.

cancer biology↗

bioRxiv2018

Functional systemic CD4 immunity is a differential factor for clinical responses to PD-L1/PD-1 blockade therapy in lung cancer

The majority of lung cancer patients progressing from conventional therapies are refractory to PD-L1/PD-1 blockade monotherapy. Here we show that baseline systemic CD4 immunity is a differential factor for clinical responses. Patients with functional systemic CD4 T cells included all objective responders and could be identified before the start of therapy by having a high proportion of memory CD4 T cells. In these patients CD4 T cells possessed significant proliferative capacities, co-expressed low levels of PD-1/LAG-3 and were responsive to PD-1 blockade ex vivo and in vivo. In contrast, patients with dysfunctional systemic CD4 immunity did not respond even though they had circulating lung cancer antigen-specific CD4 and CD8 T cells. CD4 T cells in these patients proliferated very poorly, strongly co-upregulated PD-1/LAG-3 after stimulation, and were largely refractory to PD-1 monoblockade ex vivo and in vivo. Although baseline CD8 immunity was strongly dysfunctional in all patients before the start of therapy, it only recovered in patients with functional CD4 immunity. CD4 and CD8 T cell dysfunctionality was caused by PD-1/LAG-3 co-expression, which could be reverted by PD-1/LAG-3 co-blockade. Patients with functional CD4 immunity and PD-L1 tumor positivity exhibited response rates of 70%, highlighting the contribution of CD4 immunity for efficacious PD-L1/PD-1 blockade therapy.

cell biology↗

bioRxiv2018

Radiopotentiation of Enzalutamide over Human Prostate Cancer Cells as Assessed by Real-Time Cell Monitoring

While radiotherapy is the first line of treatment for prostate cancer, androgen blockade therapies are demonstrating significant survival benefit as monotherapies. As androgen blockade can cause cell death by apoptosis, it is likely that androgen blockade will potentiate the cytotoxic activities of radiotherapy. Here we tested the potential synergistic effects of these two treatments over two human metastatic prostate cancer cells by real time growth monitoring (RTCA), androgen-sensitive LNCaP cells and androgen-resistant PC-3. Both cell lines were highly resistant to high doses of radiotherapy. A pre-treatment of LNCaP cells with IC50 concentrations of enzalutamide significantly sensitized them to radiotherapy through enhanced apoptosis. In contrast, enzalutamide resistant PC-3 cells were not sensitized to radiotherapy by androgen blockade. These results provide evidence that the enzalutamide/radiotherapy combination could maximize therapeutic responses in patients with enzalutamide-sensitive prostate cancer.

cancer biology↗

bioRxiv2018

Senescent CD4 T cells unequivocally identify primary resistance and risk of hyperprogression to PD-L1/PD-1 immune checkpoint blockade in lung cancer

The majority of lung cancer patients are refractory to PD-L1/PD-1 blockade monotherapy. This therapy may even accelerate progression and death in a group of patients called hyperprogressors. Here we demonstrate that the efficacy of PD-L1/PD-1 blockade therapy relies on baseline circulating highly-differentiated CD28- CD27- CD4 T cells (THD cells), which segregate patients in two non-overlapping groups. THD cells in cancer patients mostly comprised of central memory subsets that potently co-upregulated PD-1 and LAG3 upon antigen recognition. Low baseline THD numbers unequivocally identified intrinsic non-responders and hyperprogressors, whom aberrantly responded to therapy with a potent systemic proliferative THD cell burst. Responder patients showed significant reductions in systemic CD4 THD cells throughout therapy linked to expansion of the CD28+ CD27+ CD4 T cell compartment. Quantification of THD cells from peripheral blood samples prior to therapy allows identification of non-responders, hyperprogressors and responders, a critical issue in clinical oncology. These results place CD4 T cell responses at the center of anti-tumor immunity.

cancer biology↗