A chemokine network of T cell exhaustion and metabolic reprogramming in renal cell carcinoma

Cancer energy reprogramming and the immune responses

Cancer as an uncontrolled growth of cells due to existing mutation in host cells that may proliferate, induce angiogenesis and sometimes metastasize due to the favorable tumor microenvironment (TME). Since it kills more than any disease, biomedical science does not relent in studying the exact pathogenesis. It was believed to be a problem that lies in the nucleus of the host cells; however, recent oncology findings are shifting attention to the mitochondria as an adjuvant to cancer pathogenesis. The changes in the gene are strongly related to cellular metabolism and metabolic reprogramming. It is now understood that reprogramming the TME will have a direct effect on the immune cells' metabolism. Although there are a number of studies on immune cells' response towards tumor energy reprogramming and cancer progression, there is still no existence with the updated collation of these immune cells' response to distinct energy reprogramming in cancer studies. To this end, this mini review shed some light on cancer energy reprogramming mechanisms and enzyme degradation pathways, the cancer pathogenicity activity series involved with reduced lactate production, the specific immune cell responses due to the energy reprogramming. This study highlighted some prospects and future experiments in harnessing the host immune response towards the altered energy metabolism due to cancer.

Unraveling T cell exhaustion in the immune microenvironment of osteosarcoma via single-cell RNA transcriptome

Osteosarcoma (OS) represents a profoundly invasive malignancy of the skeletal system. T cell exhaustion (Tex) is known to facilitate immunosuppression and tumor progression, but its role in OS remains unclear. In this study, single-cell RNA sequencing data was employed to identify exhausted T cells within the tumor immune microenvironment (TIME) of OS. We found that exhausted T cells exhibited substantial infiltration in OS samples. Pseudotime trajectory analysis revealed a progressive increase in the expression of various Tex marker genes, including PDCD1, CTLA4, LAG3, ENTPD1, and HAVCR2 in OS. GSVA showed that apoptosis, fatty acid metabolism, xenobiotic metabolism, and the interferon pathway were significantly activated in exhausted T cells in OS. Subsequently, a prognostic model was constructed using two Tex-specific genes, MYC and FCGR2B, which exhibited exceptional prognostic accuracy in two independent cohorts. Drug sensitivity analysis revealed that OS patients with a low Tex risk were responsive to Dasatinib and Pazopanib. Finally, immunohistochemistry verified that MYC and FCGR2B were significantly upregulated in OS tissues compared with adjacent tissues. This study investigates the role of Tex within the TIME of OS, and offers novel insights into the mechanisms underlying disease progression as well as the potential treatment strategies for OS.

Functional and transcriptional heterogeneity within the massively expanding HLADR+CD38+ CD8 T cell population in acute febrile dengue patients

IMPORTANCE

CD8 T cells play a crucial role in protecting against intracellular pathogens such as viruses by eliminating infected cells and releasing anti-viral cytokines such as interferon gamma (IFNγ). Consequently, there is significant interest in comprehensively characterizing CD8 T cell responses in acute dengue febrile patients. Previous studies, including our own, have demonstrated that a discrete population of CD8 T cells with HLADR+ CD38+ phenotype undergoes massive expansion during the acute febrile phase of natural dengue virus infection. Although about a third of these massively expanding HLADR+ CD38+ CD8 T cells were also CD69high when examined ex vivo, only a small fraction of them produced IFNγ upon in vitro peptide stimulation. Therefore, to better understand such functional diversity of CD8 T cells responding to dengue virus infection, it is important to know the cytokines/chemokines expressed by these peptide-stimulated HLADR+CD38+ CD8 T cells and the transcriptional profiles that distinguish the CD69+IFNγ+, CD69+IFNγ-, and CD69-IFNγ- subsets.

A novel prognostic signature of chemokines for survival and immune infiltration in kidney renal clear cell carcinoma

Objective: Studies have revealed the alteration of chemokines in the tumour microenvironment in renal clear cell carcinoma (KIRC), which is closely related with immune infiltration and the prognosis of patients with KIRC. This research aims to comprehensively clarify the signature of chemokines in KIRC and the correlation between chemokines and immune infiltration in the TME of KIRC. Methods: The chemokine expression in KIRC were investigated by using multiple multiomics and bioinformatics tools. Hub-chemokines that were significantly related with the cancer stage and survival were identified. The role of hub-chemokines in the tumor microenvironment of KIRC was further assessed by using enrichment analysis, cancer-related pathway and immune infiltration analysis. Results: A total of 20 chemokines were significantly elevated in KIRC. Based on the correlation with KIRC stages and survival, 13 hub-chemokines were identified. Among the hub-chemokines, the high expression of CXCL2, CXCL5 and CXCL13 were related with worse survival of KIRC patients. The hub-chemokines were associated with the activation of multiple cancer-related signaling pathways. The functions of hub-chemokines were mainly enriched in chemokine-mediated signaling pathway, immunocytes chemotaxis and chemokine activity. CCL4, CCL5, CXCL9, CXCL10 and CXCL11 were related with various types immune infiltration such as CD8⁺T cell, neutrophil, B cell and dendritic cell. Using the hub-chemokine CXCL10, multiple immune checkpoints including LAG3, CTLA-4 and PD-1 were identified. Conclusion: Our research sheds light on the chemokines and their important role in promoting the tumor microenvironment of KIRC. The findings could provide more data about the prognosis prediction and treatment targets for KIRC.