[Exploration of cancer biological characteristics in people with different five movements and six climates constitution based on pan-cancer Bulk RNA-Seq].

According to the theory of five movements and six climates, the innate constitution plays a crucial role in determining the underlyingpa thological mechanisms of diseases later in life. Previous studies have demonstrated a close association between the constitution, as defined by the theory of five movements and six climates, and the development of various types of tumors. Furt hermore,the tumorsubtype determined by the constitution has prognostic implications. This highlights the potential of utilizing the fivemovements and six climates theory to guide the implementation of precision medicine strategies in thefield of oncology. However, no resear ch has yet been conducted to investigate the use of this theory in guiding the development of tumor molecular classification and precisi onmedicine strategies. The objective of this research is to uncover the biological characteristics of each constitution within a pancanc ercohort and identify potential anti-tumor drugs that are applicable to patients with different constitutional types. By doing so, we aimto c ontribute to the establishment of a precision medicine strategy for tumors derived from the original concepts of traditional Chi nesemedicine(TCM). In this study, we obtainedpan-cancer Bulk RNA-Seq data from UCSC Xena, GWAS cohort data from the UKBiobank, and cis-eQTLs data from eQ TLGen and GTEx V8. We employed machine learning methods to screen for hub genes associated with each constitution. Subsequently, we utilized informatics tools to explore the biological characteristics of each constitut iondefined by the theory of five movements and six bioclimates. Further, potential anti-tumor drugs suitable for patients with differen tconstitutional types were identified through mendelian randomization, molecular docking, and drug-like prediction techniques. Withinthe pan-cancer cohort, significant differences were observed among different constitutions in terms of progression-free interval, biological f unctions, immune cell abundance, tumor drug sensitivity, and immunotherapy response. These findings suggest that the five movements and six climates theory can guide tumor molecular classification and the development of precision medicine strategies. Moreover,the biological characteristics inherent to each constitution partially shed light on the scientific implications of Chinese medicinetheories, offering a fresh perspective towards clinical cancer treatment. Through molecular docking and drug-like prediction, several po tential anti-tumor drugs such as 17-beta-estradiol, serotonin, trans-resveratrol, and linoleic acid were identified. Overall, the util izationof multi-omics approaches pro vides a powerful tool to unravel the scientific foundations of TCM theories. The elucidation of themu lti-omics features associated witheach constitution in tumors serves as the basis for applying the five movements and six climates theoryto tumor molecular classification and the development of precision medicine strategies.

NIR-II light powered hydrogel nanomotor for intravesical instillation with enhanced bladder cancer therapy.

Intravesical instillation is the common therapeutic strategy for bladder cancer. Besides chemo drugs, nanoparticles are used as intravesical instillation reagents, offering appealing therapeutic approaches for bladder cancer treatment. Metal oxide nanoparticle based chemodynamic therapy (CDT) converts tumor intracellular hydrogen peroxide to ROS with cancer cell-specific toxicity, which makes it a promising approach for the intravesical instillation of bladder cancer. However, the limited penetration of nanoparticle based therapeutic agents into the mucosa layer of the bladder wall poses a great challenge for the clinical application of CDT in intravesical instillation. Herein, we developed a 1064 nm NIR-II light driven hydrogel nanomotor for the CDT for bladder cancer via intravesical instillation. The hydrogel nanomotor was synthesized via microfluidics, wrapped with a lipid bilayer, and encapsulates CuO2 nanoparticles as a CDT reagent and core-shell structured Fe3O4@Cu9S8 nanoparticles as a fuel reagent with asymmetric distribution in the nanomotor (LipGel-NM). An NIR-II light irradiation of 1064 nm drives the active motion of LipGel-NMs, thus facilitating their distribution in the bladder and deep penetration into the mucosa layer of the bladder wall. After FA-mediated endocytosis in bladder cancer cells, CuO2 is released from LipGel-NMs due to the acidic intracellular environment for CDT. The NIR-II light powered active motion of LipGel-NMs effectively enhances CDT, providing a promising strategy for bladder cancer therapy.

ZMYND8 protects breast cancer stem cells against oxidative stress and ferroptosis through activation of NRF2.

Breast cancer stem cells (BCSCs) mitigate oxidative stress to maintain their viability and plasticity. However, the regulatory mechanism of oxidative stress in BCSCs remains unclear. We recently found that the histone reader ZMYND8 was upregulated in BCSCs. Here, we showed that ZMYND8 reduced ROS and iron to inhibit ferroptosis in aldehyde dehydrogenase-high (ALDHhi) BCSCs, leading to BCSC expansion and tumor initiation in mice. The underlying mechanism involved a two-fold posttranslational regulation of nuclear factor erythroid 2-related factor 2 (NRF2). ZMYND8 increased stability of NRF2 protein through KEAP1 silencing. On the other hand, ZMYND8 interacted with and recruited NRF2 to the promoters of antioxidant genes to enhance gene transcription in mammospheres. NRF2 phenocopied ZMYND8 to enhance BCSC stemness and tumor initiation by inhibiting ROS and ferroptosis. Loss of NRF2 counteracted ZMYND8's effects on antioxidant genes and ROS in mammospheres. Interestingly, ZMYND8 expression was directly controlled by NRF2 in mammospheres. Collectively, these findings uncover a positive feedback loop that amplifies the antioxidant defense mechanism sustaining BCSC survival and stemness.

A Biomimetic Nociceptor Using Centrosymmetric Crystals for Machine Intelligence.

Pain sensation is a crucial aspect of perception in the body. Force-activated nociceptors encode electrochemical signals and yield multilevel information of pain, thus enabling smart feedback. Inspired by the natural template, multi-dimensional mechano-sensing materials provide promising approaches for biomimetic nociceptors in intelligent terminals. However, the reliance on non-centrosymmetric crystals has narrowed the range of these materials. Here centrosymmetric crystal Cr3+ -doped zinc gallogermanate (ZGGO:Cr) with multi-dimensional mechano-sensing is reported, eliminating the limitation of crystal structure. Under forces, ZGGO:Cr generates electrical signals imitating those of neuronal systems, and produces luminescence for spatial mapping of mechanical stimuli, suggesting a path toward bionic pain perception. On that basis, a wireless biomimetic nociceptor system is developed and a smart pain reflex in a robotic hand and robot-assisted biopsy surgery of rat and dog is achieved.

Aqueous Humor Liquid Biopsy as a Companion Diagnostic for Retinoblastoma: Implications for Diagnosis, Prognosis, and Therapeutic Options: Five Years of Progress.

PURPOSE: To define the prospective use of the aqueous humor (AH) as a molecular diagnostic and prognostic liquid biopsy for retinoblastoma (RB). METHODS: This is a prospective, observational study wherein an AH liquid biopsy is performed at diagnosis and longitudinally through therapy for patients with RB. Tumor-derived cell-free DNA is isolated and sequenced for single nucleotide variant analysis of the RB1 gene and detection of somatic copy number alterations (SCNAs). The SCNAs are used to determine tumor fraction (TFx). Specific SCNAs, including 6p gain and focal MycN gain, along with TFx, are prospectively correlated with intraocular tumor relapse, response to therapy, and globe salvage. RESULTS: A total of 26 eyes of 21 patients were included with AH taken at diagnosis. Successful ocular salvage was achieved in 19 of 26 (73.1%) eyes. Mutational analysis of 26 AH samples identified 23 pathogenic RB1 variants and 2 focal RB1 deletions; variant allele fraction ranged from 30.5% to 100% (median 93.2%). At diagnosis, SCNAs were detectable in 17 of 26 (65.4%) AH samples. Eyes with 6p gain and/or focal MycN gain had significantly greater odds of poor therapeutic outcomes (odds ratio = 6.75, 95% CI = 1.06-42.84, P = .04). Higher AH TFx was observed in eyes with vitreal progression (TFx = 46.0% ± 40.4) than regression (22.0 ± 29.1; difference: -24.0; P = .049). CONCLUSIONS: Establishing an AH liquid biopsy for RB is aimed at addressing (1) our inability to biopsy tumor tissue and (2) the lack of molecular biomarkers for intraocular prognosis. Current management decisions for RB are made based solely on clinical features without objective molecular testing. This prognostic study shows great promise for using AH as a companion diagnostic. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Oncological and surgical outcomes of radical surgery in elderly colorectal cancer patients with intestinal obstruction.

Background: The treatment strategy for elderly colorectal cancer patients with intestinal obstruction remains controversial. The choice of reasonable treatment and surgical method directly affects perioperative safety and prognosis. This study investigated the safety and long-term efficacy of radical surgery in elderly colorectal cancer patients over 80 years old with intestinal obstruction. Methods: The clinicopathological data of elderly patients over 80 years old with intestinal obstruction who underwent colorectal cancer surgery from January 2012 to December 2021 were retrospectively collected and analysed. Patients were assigned to a radical group and a palliative group according to the surgical method. Propensity score matching (PSM) was performed to match patients in the radical group 1:1 with those in the palliative group. The perioperative-related indexes and prognosis were compared between the two groups. Results: A total of 187 patients were enrolled in this study. After PSM, 58 matched pairs were selected, and the radical and palliative groups were well balanced in terms of the clinical and surgical characteristics (P > 0.05). The proportion of patients transferred to the ICU after surgery in the radical group was significantly higher than that in the palliative group (17.2% vs. 5.2%, P = 0.039). In terms of postoperative complications, the incidence of grade 1-5 complications in the radical group was significantly higher than that in the palliative group (37.9% vs. 15.5%, P = 0.006); however, there was no significant difference in the incidence of grade 3-5 complications between the two groups (6.9% vs. 1.7%, P = 0.364). In addition, the complications were subclassified, and it was found that the incidence of gastrointestinal disorders (20.7% vs. 6.9%, P = 0.031) after surgery was significantly higher in the radical group. The 3-year OS rates were 55.2% and 22.6% in the radical and palliative groups, respectively (P < 0.001). Multivariate analysis revealed that radical surgery was an independent prognostic factor for OS (HR: 4.32; 95% CI, 1.93-12.45; P < 0.001). Conclusion: Although elderly colorectal cancer patients over 80 years of age with intestinal obstruction are more likely to be admitted to the ICU and develop more postoperative complications after radical surgery, long-term survival benefits can be achieved.

SAP30 promotes breast tumor progression by bridging the transcriptional corepressor SIN3 complex and MLL1.

SAP30 is a core subunit of the transcriptional corepressor SIN3 complex, but little is known about its role in gene regulation and human cancer. Here, we show that SAP30 was a nonmutational oncoprotein upregulated in more than 50% of human breast tumors and correlated with unfavorable outcomes in patients with breast cancer. In various breast cancer mouse models, we found that SAP30 promoted tumor growth and metastasis through its interaction with SIN3A/3B. Surprisingly, the canonical gene silencing role was not essential for SAP30's tumor-promoting actions. SAP30 enhanced chromatin accessibility and RNA polymerase II occupancy at promoters in breast cancer cells, acting as a coactivator for genes involved in cell motility, angiogenesis, and lymphangiogenesis, thereby driving tumor progression. Notably, SAP30 formed a homodimer with 1 subunit binding to SIN3A and another subunit recruiting MLL1 through specific Phe186/200 residues within its transactivation domain. MLL1 was required for SAP30-mediated transcriptional coactivation and breast tumor progression. Collectively, our findings reveal that SAP30 represents a transcriptional dependency in breast cancer.

Cancer Cell-Selective Membrane Receptor Clustering Driven by VEGF Secretion for In Vivo Therapy.

Clustering of cell membrane receptors regulates cell behaviors. Although receptor clustering plans have achieved wide applications in cancer therapy, it still remains challenging to manipulate receptor clustering selectively for cancer cells with little influence on normal cells. Here, we design a Raji cell Selective MAnipulation of Receptor Clustering (SMARC) strategy for CD20, which is driven by endogenous secretion of Raji cells. Retractable DNA nanostrings with repeating hairpin-structured units are anchored to the cell membrane CD20, which contract in response to Raji cell-secreted vascular endothelial growth factor (VEGF) with corresponding CD20 clustering. The contraction of DNA nanostrings is intensified via a VEGF amplifier including DNA cyclic reactions to continuously trigger the foldings of hairpin-structured units in DNA nanostrings. The SMARC strategy shows selective and efficient apoptosis of Raji cells with little interference to normal B cells and demonstrates good in vivo therapeutic efficacy, which provides a promising tool for precise cancer therapy.

Serum Rcn3 level is a potential diagnostic biomarker for connective tissue disease-associated interstitial lung disease and reflects the severity of pulmonary function.

BACKGROUND: Although reticulocalbin 3 (Rcn3) has a critical role in alveolar epithelial function as well as in pathogenesis of pulmonary fibrosis, no study has yet examined its diagnostic and prognostic values for interstitial lung disease (ILD). This study aimed to evaluate Rcn3 as a potential marker in differential diagnosis of idiopathic pulmonary fibrosis (IPF) and connective tissue disease-associated interstitial lung disease (CTD-ILD) and in reflecting the severity of disease. METHODS: This was a retrospective observational pilot study included 71 ILD patients and 39 healthy controls. These patients were stratified into IPF group (39) and CTD-ILD group (32). The severity of ILD was evaluated through pulmonary function test. RESULTS: Serum Rcn3 level was statistically higher in CTD-ILD patients than that in IPF patients (p = 0.017) and healthy controls (p = 0.010). Serum Rcn3 further showed statistically negative correlation with pulmonary function indexes (TLC% pred and DLCO% pred) and positive correlation with inflammatory indexes (CRP and ESR) (r = - 0.367, p = 0.039; r = - 0.370, p = 0.037; r = 0.355, p = 0.046; r = 0.392, p = 0.026, respectively) in CTD-ILD patients rather than IPF patients. ROC analysis demonstrated that serum Rcn3 had superior diagnostic value for CTD-ILD and a cutoff value of 2.73 ng/mL had a sensitivity of 69%, a specificity of 69% and an accuracy of 45% for diagnose of CTD-ILD. CONCLUSIONS: Serum Rcn3 levels might be a clinically useful biomarker in screening and evaluating CTD-ILD.

NIR-II Light Powered Asymmetric Hydrogel Nanomotors for Enhanced Immunochemotherapy.

Nanomotors are appealing drug carriers, and the strength of the propelling force is important for their motion capability. Though high motion efficiency has been achieved with 808 nm light driven Janus-structured noble metal nanomotors, the NIR-I light penetration depth and material biocompatibility limit their broad application. Herein, we develop a 1064 nm NIR-II light driven asymmetric hydrogel nanomotor (AHNM) with high motion capability and load it with doxorubicin for enhanced immunochemotherapy. Magnetic field assisted photopolymerization generates an asymmetric distribution of Fe3 O4 @Cu9 S8 nanoparticles in the AHNM, producing self-thermophoresis as driving force under NIR-II irradiation. The AHNM is also functionalized with dopamine for the capture and retention of tumor-associated antigens to boost immune activation. The as-obtained NIR-II light driven AHNM has a high tumor tissue penetration capability and enhances immunochemotherapy, providing a promising strategy for cancer therapy.

Single-cell RNA-sequencing technology demonstrates the heterogeneity between aged prostate peripheral and transitional zone.

BACKGROUND: Identifying cellular and functional heterogeneity within aged prostate is critical for understanding the spatial distribution of prostate diseases. METHODS: Aged human prostate peripheral zone (PZ) and transitional zone (TZ) tissues were used for single-cell RNA-sequencing. Results were validated by immunofluorescence staining. RESULTS: We found that club/hillock epithelial cells, compared with other epithelial cells, had significantly higher NOTCH signaling activity and expressed higher levels of neuro-stems but lower androgen-related genes. These cells were primarily found in the TZ and provided a stem-like niche around the proximal prostate ducts. Significant heterogeneity was observed in the aged luminal population. A novel TFF3+ luminal subtype with elevated MYC and E2F pathway activities was observed, primarily in the PZ. Further analysis revealed that epithelial cells in the TZ had higher levels of stem- and inflammation-related pathway activities but lower androgen/lineage-related pathway activities than those in the PZ. Notably, the activation of MYC, E2F and DNA repair pathways significantly increased in PZ luminal cells. In the immune landscape, we found that the immune microenvironment in the TZ is more complex and disordered with more infiltration of NK and Treg cells. CD8 T cell and macrophage in the TZ exhibit both inflammation activation and suppression phenotypes. In the stroma, the TZ had a higher fibroblast density, and fibroblasts in the TZ exhibited stronger transcriptome activity in immunity and proliferation. Ligand-receptor interaction analysis revealed that fibroblasts could contribute to a NOTCH signaling niche for club/hillock cells in the TZ and balance the prostate immune microenvironment. The activation of stem properties, inflammatory infiltration and loss of androgen/lineage activity are prominent features distinguishing the TZ from PZ. CONCLUSIONS: Our study explains the heterogeneity between the TZ and PZ of aged prostate, which may help understand the spatial distribution of prostate diseases and establish a foundation for novel target discovery.

Screening T-Cell Activity via a Photodetachable DNA-Copolymer Nanocage and Its Therapeutic Application.

Screening T-cell activity and selecting active ones from large ex vivo-expanded populations before reinfusion is important for the success of T-cell therapy. Cytokine secretion is the evaluation criterion of cell immune activity. Cell membrane-anchored probes and microchamber-based techniques have been used to screen cytokine secretion at the single-cell level. However, they are either easily affected by nearby cells' secretion or lack of single-cell encapsulation efficiency. Here, we design a photodetachable DNA-copolymer nanocage on the cell membrane for screening the activities of ex vivo-expanded T cells by in-situ monitoring cytokine interferon-gamma (IFN-γ) secretion. The ones with good immune activity are selected for therapeutic application. DNA-copolymer nanocage is self-assembled on a cell membrane to encapsulate a single T cell. A self-quenched IFN-γ recognition aptamer is contained in the DNA-copolymer nanocage, which recovers fluorescence in response to IFN-γ secretion to indicate individual T-cell activity. The active T cells are collected after fluorescence-activated cell sorting, irradiated with 5 min UV light to detach nanocage from the cell membrane, and continuously cocultured with downstream cells. The selected Jurkat cells and CD19 CAR-T cells showed improved capabilities for downstream cell activation and cancer cell killing. The cell membrane-detachable DNA-copolymer nanocage-based T-cell activity screening and selection would have promising applications in T-cell therapy.

ZMYND8 is a master regulator of 27-hydroxycholesterol that promotes tumorigenicity of breast cancer stem cells.

27-Hydroxycholesterol (27-HC) is the most abundant oxysterol that increases the risk of breast cancer progression. However, little is known about epigenetic regulation of 27-HC metabolism and its role in breast tumor initiation. Using genetic mouse mammary tumor and human breast cancer models, we showed here that the histone reader ZMYND8 was selectively expressed in breast cancer stem cells (BCSCs) and promoted epithelial-mesenchymal transition (EMT), BCSC maintenance and self-renewal, and oncogenic transformation through its epigenetic functions, leading to breast tumor initiation. Mechanistically, ZMYND8 was a master transcriptional regulator of 27-HC metabolism. It increased cholesterol biosynthesis and oxidation but blocked cholesterol efflux and 27-HC catabolism, leading to accumulation of 27-HC in BCSCs. Consequently, 27-HC promoted EMT, oncogenic transformation, and tumor initiation through activation of liver X receptor. These findings reveal that ZMYND8 is an epigenetic booster that drives breast tumor initiation through metabolic reprogramming.

KDM6B promotes PARthanatos via suppression of O6-methylguanine DNA methyltransferase repair and sustained checkpoint response.

Poly(ADP-ribose) polymerase-1 (PARP-1) is a DNA damage sensor and contributes to both DNA repair and cell death processes. However, how PARP-1 signaling is regulated to switch its function from DNA repair to cell death remains largely unknown. Here, we found that PARP-1 plays a central role in alkylating agent-induced PARthanatic cancer cell death. Lysine demethylase 6B (KDM6B) was identified as a key regulator of PARthanatos. Loss of KDM6B protein or its demethylase activity conferred cancer cell resistance to PARthanatic cell death in response to alkylating agents. Mechanistically, KDM6B knockout suppressed methylation at the promoter of O6-methylguanine-DNA methyltransferase (MGMT) to enhance MGMT expression and its direct DNA repair function, thereby inhibiting DNA damage-evoked PARP-1 hyperactivation and subsequent cell death. Moreover, KDM6B knockout triggered sustained Chk1 phosphorylation and activated a second XRCC1-dependent repair machinery to fix DNA damage evading from MGMT repair. Inhibition of MGMT or checkpoint response re-sensitized KDM6B deficient cells to PARthanatos induced by alkylating agents. These findings provide new molecular insights into epigenetic regulation of PARP-1 signaling mediating DNA repair or cell death and identify KDM6B as a biomarker for prediction of cancer cell vulnerability to alkylating agent treatment.

Targeting BCAT1 Combined with α-Ketoglutarate Triggers Metabolic Synthetic Lethality in Glioblastoma.

Branched-chain amino acid transaminase 1 (BCAT1) is upregulated selectively in human isocitrate dehydrogenase (IDH) wildtype (WT) but not mutant glioblastoma multiforme (GBM) and promotes IDHWT GBM growth. Through a metabolic synthetic lethal screen, we report here that α-ketoglutarate (AKG) kills IDHWT GBM cells when BCAT1 protein is lost, which is reversed by reexpression of BCAT1 or supplementation with branched-chain α-ketoacids (BCKA), downstream metabolic products of BCAT1. In patient-derived IDHWT GBM tumors in vitro and in vivo, cotreatment of BCAT1 inhibitor gabapentin and AKG resulted in synthetic lethality. However, AKG failed to evoke a synthetic lethal effect with loss of BCAT2, BCKDHA, or GPT2 in IDHWT GBM cells. Mechanistically, loss of BCAT1 increased the NAD+/NADH ratio but impaired oxidative phosphorylation, mTORC1 activity, and nucleotide biosynthesis. These metabolic alterations were synergistically augmented by AKG treatment, thereby causing mitochondrial dysfunction and depletion of cellular building blocks, including ATP, nucleotides, and proteins. Partial restoration of ATP, nucleotides, proteins, and mTORC1 activity by BCKA supplementation prevented IDHWT GBM cell death conferred by the combination of BCAT1 loss and AKG. These findings define a targetable metabolic vulnerability in the most common subset of GBM that is currently incurable. SIGNIFICANCE: Metabolic synthetic lethal screening in IDHWT glioblastoma defines a vulnerability to ΑΚG following BCAT1 loss, uncovering a therapeutic strategy to improve glioblastoma treatment. See related commentary by Meurs and Nagrath, p. 2354.

Activation of peracetic acid via Co3O4 with double-layered hollow structures for the highly efficient removal of sulfonamides: Kinetics insights and assessment of practical applications.

Sulfonamides (SAs) have been of ecotoxicological concern for ambient ecosystems due to their widespread application in the veterinary industry. Herein, we developed a powerful advanced oxidation peracetic acid (PAA) activation process for the remediation of SAs by Co3O4 with double-layered hollow structures (Co3O4 DLHSs). Systematic characterization results revealed that the polyporous hollow hierarchical structure endows Co3O4 DLHSs with abundant active reaction sites and enhanced mass transfer rate, which were conducive for improving the PAA activation efficiency. Laser flash photolysis experiment and mechanism studies indicated that organic radical species were dominant reactive species for SAs removal. The present system is also highly effective under natural water matrices and trace SAs concentration (20 µg/L) condition. More importantly, the chlorella acute toxicity of the SAs solution was eliminated during mineralization process, supporting this catalytic system may be efficaciously applied for the remediation of SAs contamination in ambient waterways.

Single cell multi-miRNAs quantification with hydrogel microbeads for liver cancer cell subtypes discrimination.

The simultaneous quantification of multi-miRNAs in single cells reveals cellular heterogeneity, and benefits the subtypes discrimination of cancer cells . Though micro-droplet techniques enable successful single cell encapsulation, the isolated and restricted reaction space of microdroplets causes cross-reactions and inaccuracy for simultaneous multi-miRNAs quantification. Herein, we develop a hydrogel microbead based strategy for the simultaneous sensitive quantification of miRNA-21, 122 and 222 in single cells. Single cells are encapsulated and undergo cytolysis in hydrogel microbeads. The three target miRNAs are retained in the microbead by pre-immobilized capture probes, and activate rolling circle amplification (RCA) reactions. The RCA products are hybridized with corresponding dye labelled DNA reporters, and the respective fluorescence intensities are recorded for multi-miRNA quantification. The porous structure of the hydrogel microbeads allows the free diffusion of reactants and easy removal of unreacted DNA strands, which effectively avoids nonspecific cross-reactions. Clear differentiation of cellular heterogeneity and subpopulation discrimination are achieved for three kinds of liver cancer cells and one normal liver cell.

Hsa_circ_0004058 inhibits apoptosis of SRA01/04 cells by promoting autophagy via miR-186/ATG7 axis.

Senile cataract is a common age-related disease in ophthalmology. Hsa_circ_0004058 has been reported to be down-regulated in the lens epithelial cells of senile cataract patients, suggesting that hsa_circ_0004058 is associated with senile cataract. However, the underlying mechanism is still unknown. This study attempted to determine the functional role of hsa_circ_0004058 in senile cataract. We treated human lens epithelial cells (SRA01/04) with H2O2 as senile cataract model, and found that cell viability and autophagy of SRA01/04 cells were severely decreased by H2O2 treatment. Hsa_circ_0004058 was notably down-regulated in H2O2-treated SRA01/04 cells. Moreover, hsa_circ_0004058 overexpression reduced apoptotic cells and the expression of Cleaved-caspase-3 and Bax, and enhanced Bcl-2 expression in H2O2-treated SRA01/04 cells. However, hsa_circ_0004058 silencing caused the opposite results. Hsa_circ_0004058 up-regulation accelerated the expression of autophagy-related proteins LC3-II/LC3-I and Beclin-1 in H2O2-treated SRA01/04 cells, which was partly abolished by 3-Methyladenine (autophagy inhibitor). Additionally, hsa_circ_0004058 functioned as a competing endogenous RNA to competitive binding miR-186, and thus accelerated the expression of its down-stream target, ATG7. Hsa_circ_0004058 promoted autophagy of SRA01/04 cells by regulating miR-186/ATG7 axis. In conclusion, these data demonstrates that hsa_circ_0004058 inhibits apoptosis of SRA01/04 cells by promoting autophagy, which attributes to regulate miR-186/ATG7 axis. Thus, hsa_circ_0004058 may be a potential target for senile cataract treatment.

MIF is a 3' flap nuclease that facilitates DNA replication and promotes tumor growth.

How cancer cells cope with high levels of replication stress during rapid proliferation is currently unclear. Here, we show that macrophage migration inhibitory factor (MIF) is a 3' flap nuclease that translocates to the nucleus in S phase. Poly(ADP-ribose) polymerase 1 co-localizes with MIF to the DNA replication fork, where MIF nuclease activity is required to resolve replication stress and facilitates tumor growth. MIF loss in cancer cells leads to mutation frequency increases, cell cycle delays and DNA synthesis and cell growth inhibition, which can be rescued by restoring MIF, but not nuclease-deficient MIF mutant. MIF is significantly upregulated in breast tumors and correlates with poor overall survival in patients. We propose that MIF is a unique 3' nuclease, excises flaps at the immediate 3' end during DNA synthesis and favors cancer cells evading replication stress-induced threat for their growth.

Regulation of branched-chain amino acid metabolism by hypoxia-inducible factor in glioblastoma.

Hypoxia-inducible factors (HIFs) mediate metabolic reprogramming in response to hypoxia. However, the role of HIFs in branched-chain amino acid (BCAA) metabolism remains unknown. Here we show that hypoxia upregulates mRNA and protein levels of the BCAA transporter LAT1 and the BCAA metabolic enzyme BCAT1, but not their paralogs LAT2-4 and BCAT2, in human glioblastoma (GBM) cell lines as well as primary GBM cells. Hypoxia-induced LAT1 protein upregulation is mediated by both HIF-1 and HIF-2 in GBM cells. Although both HIF-1α and HIF-2α directly bind to the hypoxia response element at the first intron of the human BCAT1 gene, HIF-1α is exclusively responsible for hypoxia-induced BCAT1 expression in GBM cells. Knockout of HIF-1α and HIF-2α significantly reduces glutamate labeling from BCAAs in GBM cells under hypoxia, which provides functional evidence for HIF-mediated reprogramming of BCAA metabolism. Genetic or pharmacological inhibition of BCAT1 inhibits GBM cell growth under hypoxia. Together, these findings uncover a previously unrecognized HIF-dependent metabolic pathway that increases GBM cell growth under conditions of hypoxic stress.