Biology subjects

Cancino, J.

Publications and source records attributed to Cancino, J..

5 recordsLinked to original sources

bioRxiv2025

Metabolic Adaptations of Prostate Cancer Cells Under Chronic Fructose Stimulation

BackgroundDietary sugars, particularly fructose, are increasingly implicated in cancer progression through their impact on tumor metabolism. However, the specific metabolic adaptations driven by fructose in prostate cancer (PCa) remain unexplored. MethodsWe investigated the metabolic consequences of chronic fructose exposure in androgen-sensitive (LNCaP) and androgen-independent (PC-3) PCa cell lines. We evaluated the expression, localization, and function of the fructose transporter Glut-5 and assessed metabolic fluxes, enzyme expression, lipid accumulation, and global metabolite profiles using molecular, imaging, and metabolomic approaches. ResultsGlut-5 was primarily localized to early endosomes under basal and fructose-stimulated conditions, suggesting a non-canonical role potentially consistent with transceptor function. Chronic fructose exposure significantly upregulated Glut-5 expression and enhanced fructose uptake, but did not alter substantially its subcellular localization. Functionally, fructose reduced lactate production and mitochondrial ATP output, indicating a metabolic shift away from glycolysis and oxidative phosphorylation. In LNCaP cells, fructose induced robust activation of de novo lipogenesis (DNL), evidenced by upregulation of FASN and G6PD, increased lipid droplet accumulation, and enhanced levels of key fatty acid metabolites (e.g., TG, EPA, DHA). In contrast, PC-3 cells exhibited a distinct metabolic response, characterized by increased ceramide and amino acid metabolites. Notably, pharmacological inhibition of lipid metabolism using etomoxir abrogated proliferation in both cell lines under fructose stimulation. ConclusionsThese findings reveal that fructose promotes a metabolic reprogramming in PCa cells that is cell type- and AR-dependent, enhancing lipogenesis and potentially contributing to tumor progression. Our study identifies Glut-5-mediated fructolysis and lipid metabolic pathways as key vulnerabilities in PCa, offering potential avenues for metabolic intervention.

cell biology↗

bioRxiv2023

Acute resistance exercise induces mitophagy and mitophagomes on subsarcolemmal clefts in human skeletal muscle: Focus on BNIP3L/NIX40 as a mitophagy flux marker

ObjectiveMitochondrial dynamics and quality control in skeletal muscle are central to healthy metabolism. Resistance exercise is a recognized tool for improving skeletal muscle function; however, its effect on mitochondria is still not fully understood. We investigated the impact of resistance exercise on mitochondrial morphology and mitophagy in human skeletal muscle. MethodsEight healthy men performed resistance exercise on one leg, and muscle biopsies were subsequently obtained from the resting leg (Rest) and the exercised leg (Ex) to measure protein abundance and mitochondrial morphology. Additionally, muscle biopsies were obtained from twelve healthy men, and the abundance of BNIP3L protein was correlated with muscle cell and whole body health markers. ResultsEx increased p-Drp1 and decreased MFN2, Parkin, and BNIP3L protein levels. Electron microscopy indicated an increase in mitochondrial circularity, cristae abnormality, and mitophagosome structures in Ex, with a marked increase in subsarcolemmal mitophagosomes. We also identified mitophagosomes outside the muscle. Experiments in human myotubes showed a severe decrease in BNIP3L protein in response to CCCP-induced mitochondrial damage with and without bafilomycin. A positive correlation was found between BNIP3L and exercise RQ, HOMA index, while a negative correlation was found with mitophagosomes abundance and VO2max. ConclusionOur study describes the effect of resistance exercise on mitochondrial dynamics and mitophagy in skeletal muscle, demonstrating induction of mitochondrial fission and mitophagy in the exercised leg. Moreover, we propose BNIP3L as a potential regulator and marker of mitophagy flux.

physiology↗

bioRxiv2021

Negative modulation of macroautophagy by HERPUD1 is counteracted by an increased ER-lysosomal network with impact in drug-induced stress cell survival

Macroautophagy and the ubiquitin proteasome system work as an interconnected network in the maintenance of cellular homeostasis. Indeed, efficient activation of macroautophagy upon nutritional deprivation is sustained by degradation of preexisting proteins by the proteasome. However, the specific substrates that are degraded by the proteasome in order to activate macroautophagy are currently unknown. By quantitative proteomic analysis we identified several proteins downregulated in response to starvation but independently of ATG5 expression. Among them, the most significant was HERPUD1, an ER protein of short-half life and a well-known substrate of the proteasome. We found that increased HERPUD1 stability by deletion of its ubiquitin-like domain (UBL) plays a negative role on basal and induced macroautophagy. Moreover, we found it triggers ER expansion by reordering the ER in crystalloid structures, but in the absence of unfolded protein response activation. Surprisingly, we found ER expansion led to an increase in the number and function of lysosomes establishing a tight network with the presence of membrane-contact sites. Importantly, a phosphomimetic S59D mutation within the UBL mimics UBL deletion on its stability and the ER-lysosomal network expansion revealing an increase of cell survival under stress conditions. Altogether, we propose stabilized HERPUD1 downregulates macroautophagy favoring instead a closed interplay between the ER and lysosomes with consequences in drug-cell stress survival. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=198 SRC="FIGDIR/small/447273v2_ufig1.gif" ALT="Figure 1"> View larger version (45K): org.highwire.dtl.DTLVardef@1136b35org.highwire.dtl.DTLVardef@1e39b7eorg.highwire.dtl.DTLVardef@1f59211org.highwire.dtl.DTLVardef@148b2b0_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2020

Autoregulatory circuit regulating basolateral cargo export from the TGN: role of the orphan receptor GPRC5A in PKD signaling and cell polarity.

The membrane transport apparatus comprises a series of separate membrane bound compartments, or transport stations, that are responsible for the synthesis, processing, transport, sorting and delivery to their final cellular destinations of most transmembrane and soluble lumenal proteins. Over the last decades the membrane transport system has been shown to be extensively regulated both by environmental inputs and by internal homeostatic signalling systems, or control systems, that operate to maintain the homeostasis and optimal functionality of the main transport stations, such as the endoplasmic reticulum and the Golgi, in the face of internal and external perturbations. The trans-Golgi network (TGN) is a major transport and processing station and the main sorting compartment of the transport apparatus. However, the mechanisms that control cargo export and sorting at the TGN have so far remained elusive. Here we focus on the sorting of basolateral cargo proteins and show that these proteins bind to the TGN localized orphan receptor GPRC5A. The cargo-GPRC5A complex triggers the activation of a signaling pathway that involves the G{beta}{gamma} subunits dependent activation of the phospholipase C beta 3 (PLC{beta}3), which inturn induces diacyl glycerol (DAG) production. DAG recruits and activates protein kinase D (PKD) and the phosphorylation of its substrates. This step results in the formation of basolateral carriers for delivery of these cargoes to the basolateral plasma membrane domain. We term this mechanism "ARTG" (AutoRegulation of TGN export). Remarkably, the impairment of ARTG pathway components, and in particular of GPRC5A, causes defects in the polarized organization of epithelial cells.

cell biology↗

bioRxiv2020

The proteasomal deubiquitinating enzyme PSMD14 regulates macroautophagy by controlling Golgi-to-ER retrograde transport

Ubiquitination regulates several biological processes. Here, we search for ubiquitin-related genes implicated in protein membrane trafficking performing a High-Content siRNA Screening including 1,187 genes of the human "ubiquitinome" using Amyloid Precursor Protein (APP) as a reporter. We identified the deubiquitinating enzyme PSMD14, a subunit of the 19S regulatory particle of the proteasome, specific for K63-Ub chains in cells, as a novel key regulator of Golgi-to-endoplasmic reticulum (ER) retrograde transport. Silencing or pharmacological inhibition of PSMD14 caused a robust and rapid inhibition of Golgi-to-ER retrograde transport which leads to a potent blockage of macroautophagy by a mechanism associated with the retention of Atg9A and Rab1A at the Golgi apparatus. Because pharmacological inhibition of the proteolytic core of the 20S proteasome did not recapitulate these effects, we concluded that PSMD14, and their K-63-Ub chains, act as a crucial regulator factor for macroautophagy by controlling Golgi-to-ER retrograde transport.

cell biology↗