Innate and adaptive immune cells from myeloid and lymphoid lineages resolve host infection or cell stress by mounting an appropriate and durable immune response. Upon sensing of cellular insults, immune cells become activated and undergo rapid and efficient functional changes to unleash biosynthesis of macromolecules, proliferation, survival, and trafficking; unprecedented events among other mammalian cells within the host. These changes must become operational within restricted timing to rapidly control the insult and to avoid tissue damage and pathogen spread. Such changes occur at high energy cost. Recent advances have established that plasticity of immune functions occurs in distinct metabolic stress features. Evidence has accumulated to indicate that specific metabolic signatures dictate appropriate immune functions in both innate and adaptive immunity. Importantly, recent studies have shed light on whether successfully manipulating particular metabolic targets is sufficient to modulate immune function and polarization, thereby offering strong therapeutic potential for various common immune-mediated diseases, including inflammation and autoimmune-associated diseases and cancer. In this review, we detail how cellular metabolism controls immune function and phenotype within T cells and macrophages particularly, and the distinct molecular metabolic programming and targets instrumental to engage this regulation.
The metabolic reprogramming of tumor cells and immune escape are two major hallmarks of cancer cells. The metabolic changes that occur during tumorigenesis, enabling survival and proliferation, are described for both solid and hematological malignancies. Concurrently, tumor cells have deployed mechanisms to escape immune cell recognition and destruction. Additionally, therapeutic blocking of tumor-mediated immunosuppression has proven to have an unprecedented positive impact in clinical oncology. Increased evidence suggests that cancer metabolism not only plays a crucial role in cancer signaling for sustaining tumorigenesis and survival, but also has wider implications in the regulation of antitumor immune signaling through both the release of signaling molecules and the expression of immune membrane ligands. Here, we review these molecular events to highlight the contribution of cancer cell metabolic reprogramming on the shaping of the antitumor immune response.
Soft-tissue sarcomas (STS) are rare tumors whose oncogenesis remains unknown and for which no common therapeutic target has yet been identified. Analysis of 318 STS by CGH array evidenced a frequent deletion affecting the DMD gene (encoding dystrophin isoforms) in 16.5% of STS, including sarcomas with complex genomics, gastrointestinal tumors (GIST), and synovial sarcomas (SS). These deletions are significantly associated with metastatic progression, thus suggesting the role of DMD downregulation in the acquisition of aggressive phenotypes. We observed that targeted deletions of DMD were restricted to the 5’ region of the gene, which is responsible for the transcription of Dp427. Analysis of STS tumors and cell lines by RNA sequencing revealed that only the Dp71 isoform was widely expressed. Dp427 depletion had no effect on cell growth or migration. However, Dp71 inhibition by shRNA dramatically reduced the cell proliferation and clonogenicity of three STS cell lines, likely by altering the cell cycle progression through the G2/M-phase. Our work demonstrates that DMD deletions are not restricted to myogenic tumors and could be used as a biomarker for metastatic evolution in STS. Dp71 seems to play an essential role in tumor growth, thus providing a potential target for future STS treatments.