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Marwitz, S.

Publications and source records attributed to Marwitz, S..

2 recordsLinked to original sources

Immune-evasion of KRAS-mutant lung adenocarcinoma mediated by cAMP response element-binding protein

cAMP response element-binding protein (CREB) mediates proliferative and inflammatory gene transcription in neurodegeneration and cancer, but its role in malignant immune-evasion of lung adenocarcinoma (LUAD) is unknown. We show that human LUAD of smokers are frequently altered along the CREB pathway and we employ mouse models to discover that KRAS-mutant LUAD co- opt CREB to evade immune rejection by tumoricidal neutrophils. For this, KRAS- driven CREB activation suppresses CXC-chemokine expression and prevents recruitment of CXCR1+ neutrophils. CREB1 is shown to be pro-tumorigenic in five different LUAD models, a function that is dependent on host CXCR1. Pharmacologic CREB blockade prevents tumor growth and restores neutrophil recruitment only when initiated before immune-evasion of KRAS-mutant LUAD. CREB and CXCR1 expression in human LUAD are compartmentalized to tumor and stromal cells, respectively, while CREB-regulated genes and neutrophils impact survival. In summary, CREB-mediated immune evasion of KRAS-mutant LUAD relies on signaling to neutrophil CXCR1 and is actionable.

cancer biology

WNT6-ACC2-induced accumulation of triacylglycerol rich lipid droplets is exploited by Mycobacterium tuberculosis

In view of emerging drug-resistant tuberculosis, host directed therapies are urgently needed to improve treatment outcomes with currently available anti-tuberculosis therapies. One option is to interfere with the formation of lipid-laden “foamy” macrophages in the infected host. Here, we provide evidence that WNT6, a member of the evolutionary conserved WNT signaling pathway, promotes foam cell formation by regulating key lipid metabolic genes including acetyl-CoA carboxylase-2 (ACC2) during pulmonary TB. In addition, we demonstrate that Mycobacterium tuberculosis (Mtb) facilitates its intracellular growth and dissemination in the host by exploiting the WNT6-ACC2 pathway. Using genetic and pharmacological approaches, we show that lack of functional WNT6 or ACC2 significantly reduces intracellular TAG levels, Mtb growth and necrotic cell death of macrophages. In combination with the anti-TB drug isoniazid, pharmacological inhibition of ACC2 improved anti-mycobacterial treatment in vitro and in vivo. Therefore, we propose the WNT6-ACC2 signaling pathway as a promising target for a host-directed therapy to reduce intracellular replication of Mtb by modulating neutral lipid metabolism.Competing Interest StatementDrs. N. Reiling and J. Brandenburg (Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany) have filed a patent application entitled ACC inhibitors as means and methods for treating mycobacterial diseases(WO2018007430A1, patent pending).View Full Text

immunology