Targeting polymerase θ impairs tumorigenesis and enhances radiosensitivity in lung adenocarcinoma.

Radioresistance remains a major obstacle to efficacious radiotherapy in non-small-cell lung cancer (NSCLC). DNA replication proteins are novel targets for radiosensitizers. POLQ is a DNA polymerase involved in DNA damage response and repair. We found that POLQ is overexpressed in NSCLC and is clinically correlated with high tumor stage, poor prognosis, increased tumor mutational burden, and ALK and TP5 mutation status; POLQ inhibition impaired lung tumorigenesis. Notably, POLQ expression was higher in radioresistant lung cancer cells than in wild-type cancer cells. Moreover, POLQ expression was further increased in radioresistant cells after radiation. Enhanced radioresistance is through a prolonged G2/M phase and faster repair of DNA damage, leading to reduced radiation-induced apoptosis. Novobiocin (NVB), a POLQ inhibitor, specifically targeted cancer cells. Genetic knockdown of POLQ or pharmacological inhibition by NVB decreased radioresistance in lung adenocarcinoma while causing little toxicity to normal pulmonary epithelial cells. In conclusion, POLQ is a promising and practical cancer-specific target to impair tumorigenesis and enhance radiosensitivity in NSCLC.

Activation of NLRP3 inflammasome in lung epithelial cells triggers radiation-induced lung injury.

BACKGROUND: Radiation-induced lung injury (RILI) is the most common and serious complication of chest radiotherapy. However, reported radioprotective agents usually lead to radiation resistance in tumor cells. The key to solving this problem is to distinguish between the response of tumor cells and normal lung epithelial cells to radiation damage. METHODS: RNA-Seq was used to recognize potential target of alleviating the progression of RILI as well as inhibiting tumor growth. The activation of NLRP3 inflammasome in lung epithelial cells was screened by qRT-PCR, western blotting, immunofluorescence, and ELISA. An in vivo model of RILI and in vitro conditioned culture model were constructed to evaluate the effect of NLRP3/interleukin-1ß on fibroblasts activation. ROS, ATP, and (NADP)+/NADP(H) level in lung epithelial cells was detected to explore the mechanism of NLRP3 inflammasome activation. The lung macrophages of the mice were deleted to evaluate the role of lung epithelial cells in RILI. Moreover, primary cells were extracted to validate the results obtained from cell lines. RESULTS: NLRP3 activation in epithelial cells after radiation depends on glycolysis-related reactive oxygen species accumulation. DPYSL4 is activated and acts as a negative regulator of this process. The NLRP3 inflammasome triggers interleukin-1ß secretion, which directly affects fibroblast activation, proliferation, and migration, eventually leading to lung fibrosis. CONCLUSIONS: Our study suggests that NLRP3 inflammasome activation in lung epithelial cells is essential for radiation-induced lung injury. These data strongly indicate that targeting NLRP3 may be effective in reducing radiation-induced lung injury in clinical settings.

Prognostic impact of tumor mutation burden and the mutation in KIAA1211 in small cell lung cancer.

BACKGROUND: Small cell lung cancer (SCLC) is a highly aggressive lung cancer subtype with poor survival and limited treatment options. Sequencing results have revealed gene mutations associated with SCLC, however, the correlation between the genomic alterations and clinical prognosis of SCLC is yet unclear. METHODS: Targeted next-generation sequencing of 62 cancer related genes was performed on 53 SCLC samples. The correlations between clinical outcomes and genomic alterations were analyzed. RESULTS: 38/62 (61.3%) candidate genes harbored some alterations, while all the SCLC samples carried at least 3 gene mutations. The most common nonsynonymous mutations included ERBB2 (95.9%), CREBBP (95.9%), and TP53 (77.6%). The median nonsynonymous tumor mutation burden (TMB) was 21.7 mutations/Mb (rang, 9.3-55.9). High TMB (> 21 mutations/Mb) was good prognostic factor in overall survival (OS) (21.7 vs. 10.4 months, P = 0.012). Multivariate analysis showed that high TMB was an independent prognostic factor. The overall survival (OS) of patients carrying KIAA1211 mutation was significantly longer than those with wild-type KIAA1211 (P < 0.001). CONCLUSIONS: The current study highlights the potential role of genomic alterations for the prognosis of SCLC. Higher TMB was associated with a better prognosis, and KIAA1211 might be a good prognostic factor in SCLC.

Cardamonin inhibits the proliferation and metastasis of non-small-cell lung cancer cells by suppressing the PI3K/Akt/mTOR pathway.

Cardamonin, a natural chalcone compound, has been reported to exert anticancer effects in several cancers. However, the specific pharmacological actions of cardamonin on human non-small-cell lung cancer (NSCLC) and the potential mechanisms still remain obscure. Here, we investigated the antineoplastic role of cardamonin in NSCLC both in vitro and in vivo. The proliferation of five NSCLC cell lines was inhibited in a dose-dependent and time-dependent manner with cardamonin treatment. In A549 and H460 cells, cardamonin induced apoptosis by activating caspase-3, upregulating Bax, and downregulating Bcl-2. In addition, cardamonin arrested cells in the G2/M phase and inhibited the expression levels of cyclin D1/CDK4. Moreover, cell migration and invasion were suppressed by reversing epithelial-mesenchymal transition with cardamonin treatment. Further study showed that cardamonin reduced the phosphorylation levels of the downstream effectors of phosphoinositide 3-kinase (PI3K), including protein kinase-B (Akt/PKB) and mammalian target of rapamycin (mTOR). Moreover, in the H460 xenograft model, cardamonin significantly retarded tumor growth. Also, in tumor tissues, we found that cardamonin treatment decreased the expression rates of Ki-67, p-Akt, and p-mTOR. These data suggest that cardamonin suppressed NSCLC cell proliferation and inhibited metastasis partly by restraining the PI3K/Akt/mTOR pathway and it might be an effective therapeutic compound for NSCLC in the future.

Involvement of endothelial CK2 in the radiation induced perivascular resistant niche (PVRN) and the induction of radioresistance for non-small cell lung cancer (NSCLC) cells.

BACKGROUND: Tumor microenvironment (TME) plays a vital role in determining the outcomes of radiotherapy. As an important component of TME, vascular endothelial cells are involved in the perivascular resistance niche (PVRN), which is formed by inflammation or cytokine production induced by ionizing radiation (IR). Protein kinase CK2 is a constitutively active serine/threonine kinase which plays a vital role in cell proliferation and inflammation. In this study, we investigated the potential role of CK2 in PVRN after IR exposure. RESULT: Specific CK2 inhibitors, Quinalizarin and CX-4945, were employed to effectively suppressed the kinase activity of CK2 in human umbilical vein endothelial cells (HUVECs) without affecting their viability. Results showing that conditioned medium from IR-exposed HUVECs increased cell viability of A549 and H460 cells, and the pretreatment of CK2 inhibitors slowed down such increment. The secretion of IL-8 and IL-6 in HUVECs was induced after exposure with IR, but significantly inhibited by the addition of CK2 inhibitors. Furthermore, IR exposure elevated the nuclear phosphorylated factor-κB (NF-κB) p65 expression in HUVECs, which was a master factor regulating cytokine production. But when pretreated with CK2 inhibitors, such elevation was significantly suppressed. CONCLUSION: This study indicated that protein kinase CK2 is involved in the key process of the IR induced perivascular resistant niche, namely cytokine production, by endothelial cells, which finally led to radioresistance of non-small cell lung cancer cells. Thus, the inhibition of CK2 may be a promising way to improve the outcomes of radiation in non-small cell lung cancer cells.

ETS-1 Induces Endothelial-Like Differentiation and Promotes Metastasis in Non-Small Cell Lung Cancer.

BACKGROUND/AIMS: Recently, endothelial-like cells originating directly from tumor cells have been revealed. However, the mechanism remains unclear. ETS-1 (E26 transformation specific-1), a key transcription factor in the generation and maturation of ECs (endothelial cells), has been reported to be overexpressed in several cancers. Here, we reveal novel regulation of the endothelial-like differentiation of NSCLC (non-small cell lung cancer) cells by ETS-1. METHODS: We up-regulated the expression of ETS-1 in NSCLC cell lines by H2O2 or lentiviral vector. Endothelial phenotypes, such as vWF (von Willebrand factor) and VE-cadherin were examined by Western blot analysis and immunofluorescence assay. Tube formation assay and phagocytotic activity assay were performed to evaluate ECs' specific features on NSCLC cells. The effect of ETS-1 on metastasis was determined by wound healing assays, transwell assays and a xenograft tumor model. To explore the role of ETS-1 in the initiation and progression of NSCLC, we examined ETS-1 levels in NSCLC cancerous tissues and paired adjacent normal tissues by immunohistochemstry and analyzed the relationship between ETS-1 levels and clinicopathological parameters, as well as patient survival. Kaplan Meier plotter database was used to assess the prognostic value of ETS-1 in NSCLC. The association between ETS-1 levels and MVD (microvessel density) was analyzed to determine their role in angiogenesis. RESULTS: With ETS-1 up-regulation, the expression of vWF and VE-cadherin was increased in NSCLC cells. Additionally, cells adopted several ECs' specific features, including enhanced tube formation ability and uptake of Dil-ac-LDL (acetylated low-density lipoprotein) and lectin. ETS-1 up-regulation also promoted cell migration, invasion and adhesion. In addition, xenograft mice arising from ETS-1 over-expressing cells had more liver metastases. In the clinical specimens, ETS-1 expression was significantly higher in NSCLC cancerous tissues than adjacent nontumorous tissues and positively associated with tumor size, T stage, N stage and clinical stage. Patients with high levels of ETS-1 expression had significantly poorer OS (overall survival) and FP (first progression) than those with low expression. Furthermore, there was a positive correlation between ETS-1 level and MVD. CONCLUSION: Collectively, our data reveal that ETS-1 can induce the differentiation of tumor cells into endothelial-like cells and further promote metastatic dissemination in NSCLC.

Hydroxyapatite Nanoparticle-Coated 3D-Printed Porous Ti6Al4V and CoCrMo Alloy Scaffolds and Their Biocompatibility to Human Osteoblasts.

Hydroxyapatite nanoparticles were prepared by hydrothermal method using calcium nitrate and phosphoric acid as precursors and ammonia aqueous solution as a pH value adjustor. The 3D-printed porous Ti6Al4V and CoCrMo alloy scaffolds were effectively coated with hydroxyapatite nanoparticles in the hydrothermal synthesis process by deposition method. Coating hydroxyapatite nanoparticles on the implant surfaces increased their biocompatibility and bioactivity. HAP-deposited Ti6Al4V or HAP-deposited CoCrMo scaffold induced no statistical increase in terms of apoptosis in hFOB1.19 cells compared with bare Ti6Al4V or bare CoCrMo. Interestingly, HAP coating groups presented CCK-8 values compared with bare groups suggesting that HAP could enhance cell proliferation.

Cyclin-dependent kinase 5 controls vasculogenic mimicry formation in non-small cell lung cancer via the FAK-AKT signaling pathway.

Vasculogenic mimicry (VM), an endothelial-independent tumor vascularization phenomenon representing functional tumor plasticity, might be the culprit behind the poor clinical outcome in classic antiangiogenesis treatment. However, the mechanism underlying VM needs to be elucidated. Cyclin-dependent kinase 5 (CDK5) has been recognized as a key factor in regulating migration and neuronal plasticity. Recently, CDK5 was associated with tumor migration and invasion and its expression levels correlated with poor clinical prognosis, indicating its important role in tumor cell plasticity. In this study, we determined the presence of VM network in the lung cancer cell line A549 by tube formation assay. Selective inhibition of CDK5 expression by roscovitine or siRNA significantly decreased VM formation in A549 cells both in vitro and in vivo and retarded tumor growth. To investigate the possible mechanism, we detected the downstream pathway of CDK5 by Western blotting and immunohistochemistry. We found that CDK5 silencing led to significant decrease in FAKSer732 and AKTSer472 phosphorylation level. Further studies showed that FAK knockdown impaired VM formation and deregulated cytoskeleton transformation of A549 cells. And these effects caused by FAK silence couldn't be reversed by adding CDK5 recombinant protein. This study indicates that CDK5 kinase activates the FAK/AKT signaling pathway to generate VM in a lung cancer cell line, which can help us develop potential therapeutic strategies against vessel-positive tumors.

The angiopoietin1-Akt pathway regulates barrier function of the cultured spinal cord microvascular endothelial cells through Eps8.

In mammalian central nervous system (CNS), the integrity of the blood-spinal cord barrier (BSCB), formed by tight junctions (TJs) between adjacent microvascular endothelial cells near the basement membrane of capillaries and the accessory structures, is important for relatively independent activities of the cellular constituents inside the spinal cord. The barrier function of the BSCB are tightly regulated and coordinated by a variety of physiological or pathological factors, similar with but not quite the same as its counterpart, the blood-brain barrier (BBB). Herein, angiopoietin 1 (Ang1), an identified ligand of the endothelium-specific tyrosine kinase receptor Tie-2, was verified to regulate barrier functions, including permeability, junction protein interactions and F-actin organization, in cultured spinal cord microvascular endothelial cells (SCMEC) of rat through the activity of Akt. Besides, these roles of Ang1 in the BSCB in vitro were found to be accompanied with an increasing expression of epidermal growth factor receptor pathway substrate 8 (Eps8), an F-actin bundling protein. Furthermore, the silencing of Eps8 by lentiviral shRNA resulted in an antagonistic effect vs. Ang1 on the endothelial barrier function of SCMEC. In summary, the Ang1-Akt pathway serves as a regulator in the barrier function modulation of SCMEC via the actin-binding protein Eps8.

Laminoplasty versus skip laminectomy for the treatment of multilevel cervical spondylotic myelopathy: a systematic review.

INTRODUCTION: Laminoplasty and skip laminectomy are two specific posterior surgical approaches for multilevel cervical spondylotic myelopathy. The objective of this study was to perform a systematic review comparing the clinical results and complications of laminoplasty and skip laminectomy in the treatment of multilevel cervical spondylotic myelopathy. MATERIALS AND METHODS: We reviewed and analyzed papers published from January 1969 to December 2012 through the Mediline, Embase, Cochrane review library, and other databases regarding the comparison between laminoplasty and skip laminectomy for multilevel cervical spondylotic myelopathy. RESULTS: One randomized controlled trial and three non-randomized controlled trials were included in this systematic review. In three studies, the preoperative and postoperative JOA score was similar in both laminoplasty and skip laminectomy groups. In addition, for recovery rate, there was no significant difference between the groups. One study reported that, regarding SF12 scores, there was no significant difference in physical health and mental health after surgery. However, regarding cervical pain, the skip laminectomy group was better than the laminoplasty group significantly. No difference was presented in postoperative ROM and the cervical lordosis between the groups. But the ROM % (post/pre) was reported to be significantly better in the skip laminectomy group in three studies. Less blood loss and shorter operation time were observed in skip laminectomy rather than laminoplasty. CONCLUSIONS: Based on the results above, the skip laminectomy group presented better outcomes in a variety of aspects: ROM % (post/pre), complication rate, surgical trauma, etc. However, as limited study samples were included in the paper, a claim of superiority of the two approaches could not be justified. Further studies are required on the comparison between laminoplasty and skip laminectomy.

Advancements in the Research of GEF-H1: Biological Functions and Tumor Associations.

Guanine nucleotide exchange factor H1 (GEF-H1) is a unique protein modulated by the GDP/GTP exchange. As a regulator of the Rho-GTPase family, GEF-H1 can be activated through a microtubule-depended mechanism and phosphorylation regulation, enabling it to perform various pivotal biological functions across multiple cellular activities. These include the regulation of Rho-GTPase, cytoskeleton formation, cellular barrier, cell cycle, mitosis, cell differentiation, and vesicle trafficking. Recent studies have revealed its crucial effect on the tumor microenvironment (TME) components, promoting tumor initiation and progress. Consequently, an in-depth exploration of GEF-H1's biological roles and association with tumors holds promise for its potential as a valuable molecular target in tumor treatment.

Enantiodivergent kinetic resolution of 4-substituted 1,2,3,4-tetrahydroquinolines employing amine oxidase.

Optically pure 1,2,3,4-tetrahydroquinolines (THQs) represent a class of important motifs in many natural products and pharmaceutical agents. While recent advances on redox biocatalysis have demonstrated the great potential of amine oxidases, all the transformations focused on 2-substituted THQs. The corresponding biocatalytic method for the preparation of chiral 4-substituted THQs is still challenging due to the poor activity and stereoselectivity of the available enzyme. Herein, we developed a biocatalytic kinetic resolution approach for enantiodivergent synthesis of 4-phenyl- or alkyl-substituted THQs. Through structure-guided protein engineering of cyclohexylamine oxidase derived from Brevibacterium oxidans IH-35 A (CHAO), the variant of CHAO (Y215H/Y214S) displayed improved specific activity toward model substrate 4-phenyl substituted THQ (0.14 U/mg, 13-fold higher than wild-type CHAO) with superior (R)-stereoselectivity (E > 200). Molecular dynamics simulations show that CHAO Y215H/Y214S allows a suitable substrate positioning in the expanded binding pocket to be facilely accessed, enabling enhanced activity and stereoselectivity. Furthermore, a series of 4-alkyl-substituted THQs can be transformed by CHAO Y215H/Y214S, affording R-isomers with good yields (up to 50 %) and excellent enantioselectivity (up to ee > 99 %). Interestingly, the monoamine oxidase from Pseudomonas fluorescens Pf0-1 (PfMAO1) with opposite enantioselectivity was also mined. Together, this system enriches the kinetic resolution methods for the synthesis of chiral THQs.

The efficacy and safety of apatinib in patients with heavily pretreated end-stage cancer: a retrospective study.

Background: Anti-angiogenesis therapy has been a vital treatment option in a variety of cancers. Assessing the efficacy and safety of apatinib in patients with heavily pretreated end-stage cancer is essential. Methods: Thirty patients with end-stage cancer who were heavily pretreated were enrolled in this study. All patients received oral administration of apatinib (125-500 mg/d) between May 2015 and November 2016. Dose reduction or elevation was conducted based on adverse events and doctors' judgments. Results: Prior to the apatinib treatment, the enrolled patients received a median of 1.2 surgeries (range, 0-7), 1.6 sessions of radiotherapies (range, 0-6), and 10.2 cycles of chemotherapy (range, 0-60); 43.3% of patients had uncontrolled local lesions, 83.3% of patients had uncontrolled multiple metastases, and 30.0% of patients had both. After the treatment, 25 patients had valuable data, 6 (24.0%) patients achieved partial response (PR), and 12 (48.0%) patients had stable disease (SD). The disease control rate (DCR) was 72.0%. The PR and SD rates were 20.0% and 40.0%, respectively, and the DCR was 60.0% in the intent-to-treat (ITT) analysis. Meanwhile, the median progression-free survival (PFS) was 2.6 (range, 0.7-5.4) months, and the median overall survival (OS) was 3.8 (range, 1.0-12.0) months. Furthermore, the PR rate and DCR in patients with squamous cell cancer (SCC) were 45.5% and 81.8%, respectively; those in patients with adenocarcinoma (ADC) were 8.3% and 58.3%, respectively. The adverse events were generally mild. The most common adverse events were hyperbilirubinemia (53.3%), elevated transaminase (36.7%), anemia (30.0%), thrombocytopenia (30.0%), hematuria (30.0%), fatigue (26.7%), and leukopenia (20.0%). Conclusions: The results of this study demonstrate the efficacy and safety of apatinib and support the further development of apatinib as a potential treatment option for patients with heavily pretreated end-stage cancer.

Deficiency of Carbamoyl Phosphate Synthetase 1 Engenders Radioresistance in Hepatocellular Carcinoma via Deubiquitinating c-Myc.

PURPOSE: Tumor radiation resistance is the main obstacle to effective radiation therapy for patients with hepatocellular carcinoma (HCC). We identified the role of urea cycle key enzyme carbamoyl phosphate synthetase 1 (CPS1) in radioresistance of HCC and explored its mechanism, aiming to provide a novel radiosensitization strategy for the CPS1-deficiency HCC subtype. METHODS AND MATERIALS: The expression of CPS1 was measured by western blot and immunohistochemistry. Cell growth assay, EdU assay, cell apoptosis assay, cell cycle assay, clone formation assay, and subcutaneous tumor assay were performed to explore the relationship between CPS1 and radioresistance of HCC cells. Lipid metabonomic analysis was used for investigating the effects of CPS1 on lipid synthesis of HCC cells. RNA sequencing and coimmunoprecipitation assay were carried out to reveal the mechanism of CPS1 participating in the regulation of HCC radiation therapy resistance. Furthermore, 10074-G5, the specific inhibitor of c-Myc, was administered to HCC cells to investigate the role of c-Myc in CPS1-deficiency HCC cells. RESULTS: We found that urea cycle key enzyme CPS1 was frequently lower in human HCC samples and positively associated with the patient's prognosis. Functionally, the present study proved that CPS1 depletion could accelerate the development of HCC and induce radiation resistance of HCC in vitro and in vivo, and deficiency of CPS1 promoted the synthesis of some lipid molecules. Regarding the mechanism, we uncovered that inhibition of CPS1 upregulated CyclinA2 and CyclinD1 by stabilizing oncoprotein c-Myc at the posttranscriptional level and generated radioresistance of HCC cells. Moreover, inactivation of c-Myc using 10074-G5, a specific c-Myc inhibitor, could partially attenuate the proliferation and radioresistance induced by depletion of CPS1. CONCLUSIONS: Our results recapitulated that silencing CPS1 could promote HCC progression and radioresistance via c-Myc stability mediated by the ubiquitin-proteasome system, suggesting that targeting c-Myc in CPS1-deficiency HCC subtype may be a valuable radiosensitization strategy in the treatment of HCC.

Importance of timing and training to implement awake prone positioning in patients with COVID-19: a single-center prospective observational study.

Background: Awake prone positioning (APP) is broadly implemented in patients with severe acute respiratory syndrome coronavirus 2 related disease [coronavirus disease 2019 (COVID-19)] admitted to hospital with severe respiratory distress syndrome. This prospective observational study aimed to explore the factors influencing the implementation of APP in patients with acute respiratory failure due to COVID-19. Methods: Patients with COVID-19, all hospitalized with positive X-ray findings and oxygen supplementation requirement, in the Respiratory Step-Down Unit of the Peking University Third Hospital between January 6th, 2023, and January 20th, 2023, were included in this study. Data regarding basic information, activities of daily living (ADLs) scores, oxygen therapy, vital signs, and duration of APP were collected to investigate the factors influencing prone positioning. Results: Among the 134 patients included, 55.2% showed an improvement in oxygen saturation 1 hour after APP. Logistic regression revealed that the pre-APP heart rate (HR) [odds ratio (OR) =1.032; P=0.046] and peripheral oxygen saturation (SpO2) (OR =0.720; P<0.001) were the associated factors of the improvement in SpO2 after treatment. Multiple linear regression revealed that the ADL scores and pre-APP respiratory rate (RR) were the associated factors of the duration of prone positioning (P<0.01). The APP technical steering group effectively improved duration of APP. Conclusions: Patients with low SpO2 and increased HR before treatment showed greater improvement in oxygen saturation. Patients with lower tolerance to ADL but lower RRs were those to demonstrate a longer duration of prone positioning. This is pointing towards establishing the most favorable time window for APP during the course of COVID-19: after the ADLs have already decreased, but before significant tachypnea has appeared.

Pretreatment serum albumin-to-alkaline phosphatase ratio is an independent prognosticator of survival in patients with metastatic gastric cancer.

BACKGROUND: Previous studies have suggested that a low albumin-to-alkaline phosphatase ratio (AAPR) is associated with a lower survival rate in patients with various malignancies. However, the relationship between pretreatment AAPR and the prognosis of patients with gastric cancer (GC) remains unclear. AIM: To investigate the prognostic value of AAPR in distant metastatic GC. METHODS: A total of 191 patients with distant metastatic cancer from a single institute were enrolled in this study. Pretreatment clinical data, including serum albumin and alkaline phosphatase levels, were collected. A chi-square test or Fisher's exact test was applied to evaluate the correlations between AAPR and various clinical parameters in GC patients. The Kaplan-Meier method and Cox proportional hazards regression model were used to evaluate the prognostic efficacy of AAPR in metastatic GC patients. A two-sided P value lower than 0.05 was considered statistically significant. RESULTS: A receiver operating characteristic curve indicated that 0.48 was the optimal threshold value for AAPR. AAPR ≤ 0.48 was significantly associated with bone (P < 0.05) and liver metastasis (P < 0.05). Patients with high levels of AAPR had better survival in terms of overall survival (OS) and progression-free survival (PFS), regardless of the presence of liver/bone metastasis. Pretreatment AAPR was found to be a favorable predictor of OS and PFS based on a multivariate cox regression model. AAPR-M system, constructed based on AAPR and number of metastatic sites, showed superior predictive ability relative to the number of metastatic sites for predicting survival. CONCLUSION: Pretreatment AAPR may serve as an independent prognostic factor for predicting PFS and OS in patients with metastatic GC. Furthermore, AAPR may assist clinicians with individualizing treatment.

Activated amino acid response pathway generates apatinib resistance by reprograming glutamine metabolism in non-small-cell lung cancer.

The efficacy of apatinib has been confirmed in the treatment of solid tumors, including non-small-cell lung cancer (NSCLC). However, the direct functional mechanisms of tumor lethality mediated by apatinib and the precise mechanisms of drug resistance are largely unknown. In this study, we demonstrated that apatinib could reprogram glutamine metabolism in human NSCLC via a mechanism involved in amino acid metabolic imbalances. Apatinib repressed the expression of GLS1, the initial and rate-limiting enzyme of glutamine catabolism. However, the broken metabolic balance led to the activation of the amino acid response (AAR) pathway, known as the GCN2/eIF2α/ATF4 pathway. Moreover, activation of ATF4 was responsible for the induction of SLC1A5 and ASNS, which promoted the consumption and metabolization of glutamine. Interestingly, the combination of apatinib and ATF4 silencing abolished glutamine metabolism in NSCLC cells. Moreover, knockdown of ATF4 enhanced the antitumor effect of apatinib both in vitro and in vivo. In summary, this study showed that apatinib could reprogram glutamine metabolism through the activation of the AAR pathway in human NSCLC cells and indicated that targeting ATF4 is a potential therapeutic strategy for relieving apatinib resistance.

A novel elicitor MoVcpo is necessary for the virulence of Magnaporthe oryzae and triggers rice defense responses.

Rice blast caused by Magnaporthe oryzae is one of the most important diseases of rice. Elicitors secreted by M. oryzae play important roles in the interaction with rice to facilitate fungal infection and disease development. In recent years, several elicitor proteins have been identified in M. oryzae, and their functions and importance are increasingly appreciated. In this study, we purified a novel elicitor-activity protein from M. oryzae, which was further identified as a vanadium chloroperoxidase (MoVcpo) by MAIDL TOF/TOF MS. The purified MoVcpo induced reactive oxygen species (ROS) accumulation in host cells, up-regulated the expression of multiple defense-related genes, thus significantly enhancing rice resistance against M. oryzae. These results suggested that MoVcpo functions as a pathogen-associated molecular pattern (PAMP) to trigger rice immunity. Furthermore, MoVcpo was highly expressed in the early stage of M. oryzae infection. Deletion of MoVcpo affected spore formation, conidia germination, cell wall integrity, and sensitivity to osmotic stress, but not fungal growth. Interestingly, compared with the wild-type, inoculation with MoVcpo deletion mutant on rice led to markedly induced ROS accumulation, increased expression of defense-related genes, but also lower disease severity, suggesting that MoVcpo acts as both an elicitor activating plant immune responses and a virulence factor facilitating fungal infection. These findings reveal a novel role for vanadium chloroperoxidase in fungal pathogenesis and deepen our understanding of M. oryzae-rice interactions.

Polystyrene micro- and nano-particle coexposure injures fetal thalamus by inducing ROS-mediated cell apoptosis.

The adverse effects of plastic on adult animal and human health have been receiving increasing attention. However, its potential toxicity to fetuses has not been fully elucidated. Herein, biodistribution of polystyrene (PS) particles was determined after the maternal mice were orally given PS micro- and/or nano-particles with and without surface modifications during gestational days 1 to 17. The results showed that PS microplastics (MPs) and nanoparticles (NPs) mainly emerged in the alimentary tract, brain, uterus, and placenta in maternal mice, and only the latter infiltrated into the fetal thalamus. PS NPs and carboxyl-modified NPs induced differentially expressed genes mainly enriched in oxidative phosphorylation and GABAergic synapse. Maternal administration of PS particles during gestation led to anxiety-like behavior of the progenies and their γ-aminobutyric acid (GABA) reduction in the prefrontal cortex and amygdala at Week 8. N-Acetylcysteine (NAC), an antioxidant, alleviated PS particles-induced oxidative injury in the fetal brain and rescued the anxiety-like behavior of the progenies. Additionally, PS nanoparticles caused excessive ROS and apoptosis in neuronal cell lines, which were prevented by glutathione supplementation. These results suggested that PS particles produced a negative effect on fetuses by inducing oxidative injury and suppressing GABA synthesis in their brain. The findings contribute to estimating the risk for PS particles to human and animal health.