bims-stacyt Biomed News
on Metabolism and the paracrine crosstalk between cancer and the organism
Issue of 2025–05–11
four papers selected by
Cristina Muñoz Pinedo, L’Institut d’Investigació Biomèdica de Bellvitge



  1. Cancer Res. 2025 May 06.
      The integrated stress response (ISR) is an adaptive pathway hijacked by cancer cells to survive cellular stresses in the tumor microenvironment. ISR activation potently induces PD-L1, leading to suppression of anti-tumor immunity. Here, we sought to uncover additional immune checkpoint proteins regulated by the ISR to elucidate mechanisms of tumor immune escape. ISR coordinately induced CD155 and PD-L1, enhancing translation of both immune checkpoint proteins through bypass of inhibitory upstream open reading frames in their 5' UTRs. Analysis of primary human lung tumors identified a significant correlation between expression of PD-L1 and CD155. ISR activation accelerated tumorigenesis and inhibited T cell function, which could be overcome by combining PD-1 and TIGIT blockade with the ISR inhibitor ISRIB. This study uncovers a mechanism by which two immune checkpoint proteins are coordinately regulated and suggests a therapeutic strategy for lung cancer patients.
    DOI:  https://doi.org/10.1158/0008-5472.CAN-24-3844
  2. Cell Insight. 2025 Jun;4(3): 100247
      Tumor-host interactions play critical roles in cancer-associated cachexia. Previous studies have identified several cachectic proteins secreted by tumors that impair metabolic homeostasis in multiple organs, leading to host wasting. The molecular mechanisms by which malignant tumors regulate the production or secretion of these cachectic proteins, however, still remain largely unknown. In this study, we used different Drosophila cachexia models to investigate how malignant tumors regulate biosynthesis of ImpL2, a conserved cachectic protein that inhibits systemic insulin/IGF signaling and suppresses anabolism of host organs. Through bioinformatic and biochemical analysis, we found that hypoxia-inducible factor HIF-1α/Sima directly binds to the promoter region of ImpL2 gene for the first time, promoting its transcription in both tumors and non-tumor cells. Interestingly, expressing HphA to moderately suppress HIF-1α/Sima activity in adult yki 3SA gut tumors or larval scrib 1 Ras V12 disc tumors sufficiently decreased ImpL2 expression and improved organ wasting, without affecting tumor growth. We further revealed conserved regulatory mechanisms conserved across species, as intratumor HIF-1α enhances the production of IGFBP-5, a mammalian homolog of fly ImpL2, contributing to organ wasting in both tumor-bearing mice and patients. Therefore, our study provides novel insights into the mechanisms by which tumors regulate production of cachectic ligands and the pathogenesis of cancer-induced cachexia.
    DOI:  https://doi.org/10.1016/j.cellin.2025.100247
  3. Biochim Biophys Acta Rev Cancer. 2025 May 07. pii: S0304-419X(25)00086-1. [Epub ahead of print] 189344
      Tumor microenvironment (TME) refers to the local environment in which various cancer cells grow, encompassing tumor cells, adjacent non-tumor cells, and associated non-cellular elements, all of which collectively promote cancer occurrence and progression. As a principal immune component in the TME, tumor-associated macrophages (TAMs) exert a considerable influence on cancer behaviors via their interactions with cancer cells. The interactive loops between cancer cells and TAMs, including secretory factors derived from both cancer cells and TAMs, are crucial for the proliferation, stemness, drug resistance, invasion, migration, metastasis, and immune escape of various cancers. Cancer cells release paracrine proteins (HMGB1, AREG etc.), cytokines (IL-6, CCL2 etc.), RNAs (miR-21-5p, circPLEKHM1, LINC01812 etc.), and metabolites (lactic acid, succinate etc.) to regulate the polarization phenotype, mediator secretion and function of TAMs. In turn, mediators (TGF-β, IL-10, IL-6 etc.) from TAMs promote cancer progression. This review summarizes recent advancements in the interactive loops between cancer cells and TAMs in TME. Inhibiting the recruitment and M2 polarization of TAMs, reprogramming TAMs from M2 to M1 phenotype, blocking TAMs-mediated immunosuppression and immune escape, and combining with existing immunotherapy can target TAMs to overcome immunotherapy resistance in various cancers. The new breakthroughs lie in identifying effective targets for drug development, improving the drug delivery system to enhance the drug delivery efficiency, and adopting combined therapy. Interventions targeting secretory factors, cell surface receptors, and intracellular signaling pathways and metabolic modulation in the interactive loops between cancer cells and TAMs are expected to suppress cancer progression and improve therapeutic effects.
    Keywords:  Cancer cell; Cytokine; Interaction; Mediator; Tumor microenvironment; Tumor-associated macrophages
    DOI:  https://doi.org/10.1016/j.bbcan.2025.189344
  4. Sci Rep. 2025 May 04. 15(1): 15572
      Palmitic acid (PA), being the most prevalent free fatty acid in the human, holds significant implications as a risk factor for atherosclerosis (AS) due to its ability to induce physiological dysfunction in endothelial cells (ECs). Endothelial cell-specific molecule 1 (ESM1), has been identified as a marker for activated ECs. Nevertheless, the mechanisms underlying ESM1-induced endothelial cell proliferation remain elusive. The expression of ESM1, ANGPTL4 and autophagy related protein were confirmed by western blot. Proliferation ability was tested by MTT and EdU. Lipids level was confirmed by Oil red staining. Autophagic flux was confirmed by Monodansylcadaverine (MDC) staining and pCMV-mCherry-GFP-LC3B fluorescence staining assay. The mouse model of AS was used to observe the effect of PA on the ESM1-ANGPTL4-autophagy signaling axis. This study elucidates ESM1-ANGPTL4 axis in maintaining proliferation of ECs and lipid reprogramming. Furthermore, it has been observed that PA has the ability to stimulate EC to autonomously increase the expression of ESM1, which in turn can counteract the detrimental effects of PA on ECs. Conversely, when ESM1 is suppressed, the damaging effects of PA on ECs are exacerbated. Mechanistically, our findings indicate that ESM1 facilitates EC proliferation and lipids homeostasis by up-regulating autophagy through ANGPTL4. This effect of ESM1 on ECs can be attenuated by ATG7 inhibiting. Additionally, the serum levels of ESM1 were found to be elevated in AS mice. ESM1 was found to enhance ECs proliferation and mitigate endothelial cell injury induced by PA through the upregulation of autophagy. This mechanism potentially serves as a protective factor against atherosclerosis progression.
    Keywords:  ANGPTL4; Autophagy; ESM1; Endothelial cell injury; Lipid metabolism reprogramming; Palmitic acid
    DOI:  https://doi.org/10.1038/s41598-025-00581-7