bims-stacyt Biomed News
on Paracrine crosstalk between cancer and the organism
Issue of 2020‒05‒03
two papers selected by
Cristina Muñoz Pinedo
L’Institut d’Investigació Biomèdica de Bellvitge

  1. Life Sci. 2020 Apr 27. pii: S0024-3205(20)30479-3. [Epub ahead of print] 117731
    Saha J, Sarkar D, Pramanik A, Mahanti K, Adhikary A, Bhattacharyya S.
      BACKGROUND: Very little is known about the role inflammation and mechanism(s) that enables the tumor to evade host's anti-tumor immune function during very initial days of tumor establishment. Our study focuses on the immune response and local inflammation specially the pro-inflammatory and immune modifier components that are responsible for tumor-induced immune-suppression, tumor-associated macrophages (TAM) at tumor microenvironment in mouse model from very early to late phase of tumor progression.METHODS: 1 × 105 Ascites tumor, EAC in Swiss albino or Sarcoma-180 (S-180) in Balb c mice strain were inoculated intra-peritonially and grouped into Control (0 day or no tumor), initial phase (3 day tumor), early (7 Day), Late (14 day) and terminal (21 day tumor) sets. T cell activity, tumor niche macrophage, inflammatory signatures were studied using Confocal microscopy, flowcytometry, ELISA, q-RT PCR and Western blot.
    RESULTS: We observed increased T cell infiltration at a very early stage of tumorigenesis in the tumor site with elevated percentage of activated/memory T cells. But increased cellular death and functional suppression of tumor site T cells during final stages. We observed increased infiltration of TAMs with skewed M2 phenotype. Increased chemokine receptor expression could be noted on these TAMs. Using HIF-1α inhibitor and prostaglandin receptor antagonists we demonstrated crucial role of these factor in functional alteration in TAMs. HIF-1α inhibition and also by prostaglandin receptor inhibition reduced signature pro-inflammatory gene expression, migration of macrophages and T cell suppression capacity of TAMs. We also demonstrated that PGE2 can induce HIF-1α activation in relatively less hypoxic microenvironment during early stages of tumor.
    CONCLUSION: Altogether, these findings strongly suggest link between prostaglandin mediated early HIF-1α activation and subsequent hypoxia induced HIF-1α activation that further enhances prostaglandin synthesis driving the recruitment and functional alteration of tumor site macrophages.
    Keywords:  Activated/memory T cell; CD4(+)/CD8(+); EAC; HIF-1α; IL-10; IL-12; PGE2; S-180; TAM; TIL; TNF-α
  2. Mol Cell. 2020 Apr 22. pii: S1097-2765(20)30228-8. [Epub ahead of print]
    Zasłona Z, O'Neill LAJ.
      Metabolites have functions in the immune system independent of their conventional roles as sources or intermediates in biosynthesis and bioenergetics. We are still in the pioneering phase of gathering information about the functions of specific metabolites in immunoregulation. In this review, we cover succinate, itaconate, α-ketoglutarate, and lactate as examples. Each of these metabolites has a different story of how their immunoregulatory functions were discovered and how their roles in the complex process of inflammation were revealed. Parallels and interactions are emerging between metabolites and cytokines, well-known immunoregulators. We depict molecular mechanisms by which metabolites prime cellular and often physiological changes focusing on intra- and extra-cellular activities and signaling pathways. Possible therapeutic opportunities for immune and inflammatory diseases are emerging.