The phosphatidylinositol 3-kinase (PI3K) pathway is commonly activated in cancer. Tumors are potentially sensitive to PI3K pathway inhibitors, but reliable diagnostic tests that assess functional PI3K activity are lacking. Because PI3K pathway activity negatively regulates forkhead box-O (FOXO) transcription factor activity, FOXO target gene expression is inversely correlated with PI3K activity. A knowledge-based Bayesian computational model was developed to infer PI3K activity in cancer tissue samples from FOXO target gene mRNA levels and validated in cancer cell lines treated with PI3K inhibitors. However, applied to patient tissue samples, FOXO was often active in cancer types with expected active PI3K. SOD2 was differentially expressed between FOXO-active healthy and cancer tissue samples, indicating that cancer-associated cellular oxidative stress alternatively activated FOXO. To enable correct interpretation of active FOXO in cancer tissue, threshold levels for normal SOD2 expression in healthy tissue were defined above which FOXO activity is oxidative stress induced and below which PI3K regulated. In slow-growing luminal A breast cancer and low Gleason score prostate cancer, FOXO was active in a PI3K-regulated manner, indicating inactive PI3K. In aggressive luminal B, HER2, and basal breast cancer, FOXO was increasingly inactive or actively induced by oxidative stress, indicating PI3K activity. We provide a decision tree that facilitates functional PI3K pathway activity assessment in tissue samples from patients with cancer for therapy response prediction and prognosis.

Renal tubular cell death is the key factor of the pathogenesis of ischemia/reperfusion (I/R) kidney injury. Ferroptosis is a type of regulated cell death (RCD) found in various diseases. However, the underlying molecular mechanisms related to ferroptosis in renal I/R injury remain unclear. In the present study, we investigated the regulatory role of microRNAs on ferroptosis in I/R-induced renal injury. We established the I/R-induced renal injury model in rats, and H/R induced HK-2 cells injury in vitro. CCK-8 was used to measure cell viability. Fe2+ and ROS levels were assayed to evaluate the activation of ferroptosis. We performed RNA sequencing to profile the miRNAs expression in H/R-induced injury and ferroptosis. Western blot analysis was used to detect the protein expression. qRT-PCR was used to detect the mRNA and miRNA levels in cells and tissues. We further used luciferase reporter assay to verify the direct targeting effect of miRNA. We found that ischemia/reperfusion-induced ferroptosis in rat’s kidney. We identified that miR-182-5p and miR-378a-3p were upregulated in the ferroptosis and H/R-induced injury, and correlates reversely with glutathione peroxidases 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) expression in renal I/R injury tissues, respectively. In vitro studies showed that miR-182-5p and miR-378a-3p induced ferroptosis in cells. We further found that miR-182-5p and miR-378a-3p regulated the expression of GPX4 and SLC7A11 negatively by directly binding to the 3′UTR of GPX4 and SLC7A11 mRNA. In vivo study showed that silencing miR-182-5p and miR-378a-3p alleviated the I/R-induced renal injury in rats. In conclusion, we demonstrated that I/R induced upregulation of miR-182-5p and miR-378a-3p, leading to activation of ferroptosis in renal injury through downregulation of GPX4 and SLC7A11.

Tubular epithelial cells (TECs) represent the primary site of renal ischemia/reperfusion injury (RIRI). However, whether the damage of TECs could drive the initiation of inflammation was unclear. Here we investigated the role of the TECs and macrophages during RIRI. Increased expression of inflammation response and activated M1 macrophage were determined in the mice model of RIRI. Moreover, we demonstrated global miRNA expression profiling of renal exosomes, and miR-374b-5p was most upregulated in these exosomes in vivo. Inhibition of miR-374b-5p in the mice upon RIR operation would alleviate the kidney injury via decreasing the production of proinflammatory cytokines and suppressing the macrophage activation. Similar results were also identified in the hypoxia-induced cell model where exosomal miR-374b-5p was dramatically upregulated. Uptake of exosomes derived from the hypoxic TECs by macrophages would trigger M1 polarization via transferring miR-374b-5p. Besides, we confirmed that miR-374b-5p could directly bind to Socs1 using a dual-luciferase reporter assay. Notably, when we injected the miR-374b-5p-enriched exosomes into mice, a high-level inflammatory response and M1 macrophage activation were performed. Our studies demonstrated that exosomal miR-374b-5p played an essential role in the communication between injured TECs and macrophages, resulting in the M1 macrophage activation during RIRI. The blockage of the release of such exosomes may serve as a new therapeutic strategy for RIRI.

Cordycepin (3′-deoxyadenosine) is a naturally occurring adenosine analog and one of the bioactive constituents isolated from Cordyceps sinensis, species of the fungal genus Cordyceps. It has traditionally been a prized Chinese folk medicine for the human well-being. However, the actions of cordycepin against renal ischemia/reperfusion injury (I/R) are still unknown. In the present study, rats were subject to I/R and cordycepin was intragastrically administered for seven consecutive days before surgery to investigate the effects and mechanisms of cordycepin against renal I/R injury. The test results of kidney and peripheral blood samples of experimental animals showed that cordycepin significantly decreased serum blood urea nitrogen and creatinine levels and markedly attenuated cell injury. Mechanistic studies showed that cordycepin significantly regulated inflammation, apoptosis, and oxidative stress. These data provide new insights for investigating the natural product with the nephroprotective effect against I/R, which should be developed as a new therapeutic agent for the treatment of I/R in the future.

Colorectal neoplasia differentially expressed (CRNDE) served as an oncogenic long noncoding RNA (lncRNA) to be involved in the initialization and development of human cancers. However, the clinical significance and biological function of CRNDE in clear cell renal cell carcinoma (ccRCC) was not fully understood. In our study, we found CRNDE levels were increased in ccRCC tissue specimens and cell lines, and corrected with advanced clinical stage, large tumor size, lymph node metastasis, distant metastasis, and poor pathological grade in patients with ccRCC. Furthermore, levels of CRNDE were negatively correlated with overall survival of patients with ccRCC, and high-expression of CRNDE was an independent poor prognostic factor for patients with ccRCC. Moreover, loss-of-function and gain-of-function approaches showed CRNDE-enhanced ccRCC cell migration and invasion through modulating EMT-associated genes. In conclusion, CRNDE acts as an oncogenic lncRNA in ccRCC.