Ke Chen

Although substantial progress has been made in cancer biology and treatment, clinical outcomes of bladder carcinoma (BC) patients are still not satisfactory. The tumor microenvironment (TME) is a potential target. Here, by single-cell RNA sequencing on 8 BC tumor samples and 3 para tumor samples, we identify 19 different cell types in the BC microenvironment, indicating high intra-tumoral heterogeneity. We find that tumor cells down regulated MHC-II molecules, suggesting that the downregulated immunogenicity of cancer cells may contribute to the formation of an immunosuppressive microenvironment. We also find that monocytes undergo M2 polarization in the tumor region and differentiate. Furthermore, the LAMP3 + DC subgroup may be able to recruit regulatory T cells, potentially taking part in the formation of an immunosuppressive TME. Through correlation analysis using public datasets containing over 3000 BC samples, we identify a role for inflammatory cancer-associated fibroblasts (iCAFs) in tumor progression, which is significantly related to poor prognosis. Additionally, we characterize a regulatory network depending on iCAFs. These results could help elucidate the protumor mechanisms of iCAFs. Our results provide deep insight into cancer immunology and provide an essential resource for drug discovery in the future.

Immune checkpoint blockade of the inhibitory immune receptors PD-L1, PD-1 and CTLA-4 has emerged as a successful treatment strategy for several advanced cancers. Here we demonstrate that miR-424(322) regulates the PD-L1/PD-1 and CD80/CTLA-4 pathways in chemoresistant ovarian cancer. miR-424(322) is inversely correlated with PD-L1, PD-1, CD80 and CTLA-4 expression. High levels of miR-424(322) in the tumours are positively correlated with the progression-free survival of ovarian cancer patients. Mechanistic investigations demonstrated that miR-424(322) inhibited PD-L1 and CD80 expression through direct binding to the 3'-untranslated region. Restoration of miR-424(322) expression reverses chemoresistance, which is accompanied by blockage of the PD-L1 immune checkpoint. The synergistic effect of chemotherapy and immunotherapy is associated with the proliferation of functional cytotoxic CD8+ T cells and the inhibition of myeloid-derived suppressive cells and regulatory T cells. Collectively, our data suggest a biological and functional interaction between PD-L1 and chemoresistance through the microRNA regulatory cascade.

Clear-cell renal cell carcinoma (ccRCC) is the most common histological type of RCC. To investigate the intratumoral heterogeneity of ccRCC, we analyzed single-cell RNA-sequencing data and identified 15 major cell types, along with 39 subgroups of cells derived from tumor or non-malignant tissues, and confirmed their presence by immunofluorescence staining in tissue chips. In this study, we verified that T cell exhaustion was the key factor responsible for the immunosuppressive property of ccRCC tissues, which was significantly related to poor prognosis. We also found that abnormal metabolic patterns occurred not only in cancer cells, but also in tumor-infiltrating stromal cells. Based on the fraction of each cell cluster detected by CIBERSORTx, 533 patients from The Cancer Genome Atlas (TCGA) KIRC dataset were divided into three groups. One group, which showed a lesser proportion of activated CD8+ cells and greater proportion of exhausted CD8+ cells, was associated with a poor prognosis. Hence, the blockade of immunosuppressive checkpoints, not only PD-1, but also LAG3, TIM-3, and other inhibitory checkpoints, could serve as a potential target for ccRCC immunotherapy. Our work will further the understanding of the heterogeneity among ccRCC tissues and provide novel strategies for treating ccRCC. Clear-cell renal cell carcinoma (ccRCC) is the most common histological type of RCC. To investigate the intratumoral heterogeneity of ccRCC, we analyzed single-cell RNA-sequencing data and identified 15 major cell types, along with 39 subgroups of cells derived from tumor or non-malignant tissues, and confirmed their presence by immunofluorescence staining in tissue chips. In this study, we verified that T cell exhaustion was the key factor responsible for the immunosuppressive property of ccRCC tissues, which was significantly related to poor prognosis. We also found that abnormal metabolic patterns occurred not only in cancer cells, but also in tumor-infiltrating stromal cells. Based on the fraction of each cell cluster detected by CIBERSORTx, 533 patients from The Cancer Genome Atlas (TCGA) KIRC dataset were divided into three groups. One group, which showed a lesser proportion of activated CD8+ cells and greater proportion of exhausted CD8+ cells, was associated with a poor prognosis. Hence, the blockade of immunosuppressive checkpoints, not only PD-1, but also LAG3, TIM-3, and other inhibitory checkpoints, could serve as a potential target for ccRCC immunotherapy. Our work will further the understanding of the heterogeneity among ccRCC tissues and provide novel strategies for treating ccRCC.

The emergence of multidrug-resistant (MDR) Gram-negative pathogens is an urgent global medical challenge. The old polymyxin lipopeptide antibiotics (polymyxin B and colistin) are often the only therapeutic option due to resistance to all other classes of antibiotics and the lean antibiotic drug development pipeline. However, polymyxin B and colistin suffer from major issues in safety (dose-limiting nephrotoxicity, acute toxicity), pharmacokinetics (poor exposure in the lungs) and efficacy (negligible activity against pulmonary infections) that have severely limited their clinical utility. Here we employ chemical biology to systematically optimize multiple non-conserved positions in the polymyxin scaffold, and successfully disconnect the therapeutic efficacy from the toxicity to develop a new synthetic lipopeptide, structurally and pharmacologically distinct from polymyxin B and colistin. This resulted in the clinical candidate F365 (QPX9003) with superior safety and efficacy against lung infections caused by top-priority MDR pathogens Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae.

Clear cell renal cell carcinoma (ccRCC) is a complex disease with remarkable immune and metabolic heterogeneity. Here we perform genomic, transcriptomic, proteomic, metabolomic and spatial transcriptomic and metabolomic analyses on 100 patients with ccRCC from the Tongji Hospital RCC (TJ-RCC) cohort. Our analysis identifies four ccRCC subtypes including De-clear cell differentiated (DCCD)-ccRCC, a subtype with distinctive metabolic features. DCCD cancer cells are characterized by fewer lipid droplets, reduced metabolic activity, enhanced nutrient uptake capability and a high proliferation rate, leading to poor prognosis. Using single-cell and spatial trajectory analysis, we demonstrate that DCCD is a common mode of ccRCC progression. Even among stage I patients, DCCD is associated with worse outcomes and higher recurrence rate, suggesting that it cannot be cured by nephrectomy alone. Our study also suggests a treatment strategy based on subtype-specific immune cell infiltration that could guide the clinical management of ccRCC.