Targeting PPAR-gamma counteracts tumour adaptation to immune-checkpoint blockade in hepatocellular carcinoma.

OBJECTIVE: Therapy-induced tumour microenvironment (TME) remodelling poses a major hurdle for cancer cure. As the majority of patients with hepatocellular carcinoma (HCC) exhibits primary or acquired resistance to antiprogrammed cell death (ligand)-1 (anti-PD-[L]1) therapies, we aimed to investigate the mechanisms underlying tumour adaptation to immune-checkpoint targeting. DESIGN: Two immunotherapy-resistant HCC models were generated by serial orthotopic implantation of HCC cells through anti-PD-L1-treated syngeneic, immunocompetent mice and interrogated by single-cell RNA sequencing (scRNA-seq), genomic and immune profiling. Key signalling pathway was investigated by lentiviral-mediated knockdown and pharmacological inhibition, and further verified by scRNA-seq analysis of HCC tumour biopsies from a phase II trial of pembrolizumab (NCT03419481). RESULTS: Anti-PD-L1-resistant tumours grew >10-fold larger than parental tumours in immunocompetent but not immunocompromised mice without overt genetic changes, which were accompanied by intratumoral accumulation of myeloid-derived suppressor cells (MDSC), cytotoxic to exhausted CD8+ T cell conversion and exclusion. Mechanistically, tumour cell-intrinsic upregulation of peroxisome proliferator-activated receptor-gamma (PPARγ) transcriptionally activated vascular endothelial growth factor-A (VEGF-A) production to drive MDSC expansion and CD8+ T cell dysfunction. A selective PPARγ antagonist triggered an immune suppressive-to-stimulatory TME conversion and resensitised tumours to anti-PD-L1 therapy in orthotopic and spontaneous HCC models. Importantly, 40% (6/15) of patients with HCC resistant to pembrolizumab exhibited tumorous PPARγ induction. Moreover, higher baseline PPARγ expression was associated with poorer survival of anti-PD-(L)1-treated patients in multiple cancer types. CONCLUSION: We uncover an adaptive transcriptional programme by which tumour cells evade immune-checkpoint targeting via PPARγ/VEGF-A-mediated TME immunosuppression, thus providing a strategy for counteracting immunotherapeutic resistance in HCC.

A Real-Time Trajectory Prediction Method of Small-Scale Quadrotors Based on GPS Data and Neural Network.

This paper proposes a real-time trajectory prediction method for quadrotors based on a bidirectional gated recurrent unit model. Historical trajectory data of ten types of quadrotors were obtained. The bidirectional gated recurrent units were constructed and utilized to learn the historic data. The prediction results were compared with the traditional gated recurrent unit method to test its prediction performance. The efficiency of the proposed algorithm was investigated by comparing the training loss and training time. The results over the testing datasets showed that the proposed model produced better prediction results than the baseline models for all scenarios of the testing datasets. It was also found that the proposed model can converge to a stable state faster than the traditional gated recurrent unit model. Moreover, various types of training samples were applied and compared. With the same randomly selected test datasets, the performance of the prediction model can be improved by selecting the historical trajectory samples of the quadrotors close to the weight or volume of the target quadrotor for training. In addition, the performance of stable trajectory samples is significantly better than that with unstable trajectory segments with a frequent change of speed and direction with large angles.

Liquid biopsies to track trastuzumab resistance in metastatic HER2-positive gastric cancer.

OBJECTIVE: To monitor trastuzumab resistance and determine the underlying mechanisms for the limited response rate and rapid emergence of resistance of HER2+ metastatic gastric cancer (mGC). DESIGN: Targeted sequencing of 416 clinically relevant genes was performed in 78 paired plasma and tissue biopsy samples to determine plasma-tissue concordance. Then, we performed longitudinal analyses of 97 serial plasma samples collected from 24 patients who were HER2+ to track the resistance during trastuzumab treatment and validated the identified candidate resistance genes. RESULTS: The results from targeted sequencing-based detection of somatic copy number alterations (SCNA) of HER2 gene were highly consistent with fluorescence in situ hybridisation data, and the detected HER2 SCNA was better than plasma carcinoembryonic antigen levels at predicting tumour shrinkage and progression. Furthermore, most patients with innate trastuzumab resistance presented high HER2 SCNA during progression compared with baseline, while HER2 SCNA decreased in patients with acquired resistance. PIK3CA mutations were significantly enriched in patients with innate resistance, and ERBB2/4 genes were the most mutated genes, accounting for trastuzumab resistance in six (35.3%) and five (29.4%) patients in baseline and progression plasma, respectively. Patients with PIK3CA/R1/C3 or ERBB2/4 mutations in the baseline plasma had significantly worse progression-free survival. Additionally, mutations in NF1 contributed to trastuzumab resistance, which was further confirmed through in vitro and in vivo studies, while combined HER2 and MEK/ERK blockade overcame trastuzumab resistance. CONCLUSION: Longitudinal circulating tumour DNA sequencing provides novel insights into gene alterations underlying trastuzumab resistance in HER2+mGC.

LncRNA LINRIS stabilizes IGF2BP2 and promotes the aerobic glycolysis in colorectal cancer.

BACKGROUND: Long noncoding RNAs (lncRNAs) play nonnegligible roles in the epigenetic regulation of cancer cells. This study aimed to identify a specific lncRNA that promotes the colorectal cancer (CRC) progression and could be a potential therapeutic target. METHODS: We screened highly expressed lncRNAs in human CRC samples compared with their matched adjacent normal tissues. The proteins that interact with LINRIS (Long Intergenic Noncoding RNA for IGF2BP2 Stability) were confirmed by RNA pull-down and RNA immunoprecipitation (RIP) assays. The proliferation and metabolic alteration of CRC cells with LINRIS inhibited were tested in vitro and in vivo. RESULTS: LINRIS was upregulated in CRC tissues from patients with poor overall survival (OS), and LINRIS inhibition led to the impaired CRC cell line growth. Moreover, knockdown of LINRIS resulted in a decreased level of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2), a newly found N6-methyladenosine (m6A) 'reader'. LINRIS blocked K139 ubiquitination of IGF2BP2, maintaining its stability. This process prevented the degradation of IGF2BP2 through the autophagy-lysosome pathway (ALP). Therefore, knockdown of LINRIS attenuated the downstream effects of IGF2BP2, especially MYC-mediated glycolysis in CRC cells. In addition, the transcription of LINRIS could be inhibited by GATA3 in CRC cells. In vivo experiments showed that the inhibition of LINRIS suppressed the proliferation of tumors in orthotopic models and in patient-derived xenograft (PDX) models. CONCLUSION: LINRIS is an independent prognostic biomarker for CRC. The LINRIS-IGF2BP2-MYC axis promotes the progression of CRC and is a promising therapeutic target.

ELK1-induced upregulation of lncRNA HOXA10-AS promotes lung adenocarcinoma progression by increasing Wnt/ß-catenin signaling.

In recent years, increasing number of lncRNAs have been studied in lung adenocarcinoma (LAD). LncRNA HOXA10-AS was found to be upregulated in LAD tissues. Based on the data of TCGA database, HOXA10-AS was a prognostic factor for lung adenocarcinoma. This study aims to reveal the biological function of HOXA10-AS in LAD. qRT-PCR was applied to test expression levels of HOXA10-AS in both LAD tissues and cell lines. Next, transcription factor ELK1 was demonstrated to upregulate HOXA10-AS in LAD cells through performing bioinformatics analysis and dual luciferase activity. Loss of function assays were performed in two different LAD cell lines. Silenced HOXA10-AS was proved to inhibit LAD progression by affecting cell proliferation, cell apoptosis and cell metastasis and EMT progress. Western blot analysis revealed that HOXA10-AS increased Wnt/ß-catenin signaling in LAD cell lines. Finally, rescue assays were carried out to identify the biological function of HOXA10-AS-Wnt/ß-catenin signaling in LAD progression. In conclusion, ELK1-induced upregulation of HOXA10-AS improved LAD progression through increasing Wnt/ß-catenin signaling.

Typical airborne quinones modulate oxidative stress and cytokine expression in lung epithelial A549 cells.

Quinones that exist in ambient particulate matter (PM) are hypothesized to be associated with adverse health effects through the generation of reactive oxygen species (ROS). However, the impacts of the quinones on the inflammatory processes have yet to be clearly understood. In this study, we examined the oxidative potentials and biological effects of typical airborne quinones in the human lung epithelial A549 cells. Significant change of redox status, loss of mitochondrial membrane potentials (△Ψ) and increase of superoxide dismutase (SOD) activity were induced by exposure to quinones. Some pro-inflammatory genes including interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor (TNF-α) and monocyte chemoattractant protein-1 (MCP-1); two aromatic hydrocarbon receptor-regulated genes, cytochromes P450 1A1 (Cyp1a1) and cytochromes P450 1B1 (Cyp1b1); and oxidative stress-related gene heme oxygenase-1 (HO-1) were up-regulated after quinones treatment. Among these quinones, 1,2-naphthoquinone (1,2-NQ) up-regulated expressions of IL-6, IL-8, TNF-α, Cyp1a1, and HO-1; 2-methoxy-1,4-naphthoquinone (MNQ) up-regulated MCP-1, Cyp1b1, Cyp1a1, and HO-1; 2-methylanthraquinone (MAQ) up-regulated IL-6, IL-8, TNF-α, MCP-1, Cyp1b1, and Cyp1a1; acenaphthenequinone (ACQ) up-regulated IL-8, TNF-α, MCP-1, Cyp1b1, and Cyp1a1. These results suggested that all these five quinones had a considerable pro-inflammatory potential by inducing oxidative stress and releasing different types of cytokines/chemokines.

Pre-clinical evaluation of cinobufotalin as a potential anti-lung cancer agent.

Lung cancer is a major cause of cancer-related mortality in the United States and around the world. Due to the pre-existing or acquired chemo-resistance, the current standard chemotherapy regimens only show moderate activity against lung cancer. In the current study, we explored the potential anti-lung cancer activity of cinobufotalin in vivo and in vitro, and studied the underlying mechanisms. We demonstrated that cinobufotalin displayed considerable cytotoxicity against lung cancer cells (A549, H460 and HTB-58 lines) without inducing significant cell apoptosis. Our data suggest that mitochondrial protein cyclophilin D (Cyp-D)-dependent mitochondrial permeability transition pore (mPTP) opening mediates cinobufotalin-induced non-apoptotic death of lung cancer cells. The Cyp-D inhibitor cyclosporine A (CsA), the mPTP blocker sanglifehrin A (SfA), and Cyp-D shRNA-silencing significantly inhibited cinobufotalin-induced mitochondrial membrane potential (MMP) reduction and A549 cell death (but not apoptosis). Using a mice xenograft model, we found that cinobufotalin inhibited A549 lung cancer cell growth in vivo. Thus, cinobufotalin mainly induces Cyp-D-dependent non-apoptotic death in cultured lung cancer cells. The results of this study suggest that cinobufotalin might be further investigated as a novel anti-lung cancer agent.

The mitochondrial cyclophilin D/p53 complexation mediates doxorubicin-induced non-apoptotic death of A549 lung cancer cells.

Doxorubicin has displayed significant cytotoxic effects against the lung cancer cells; however, the underlying mechanisms remain inconclusive. In the current study, we provided evidence to show that mitochondrial p53 and cyclophilin D (Cyp-D) complexation is required for doxorubicin-induced death of lung cancer A549 cells. Doxorubicin induced both apoptotic and non-apoptotic death of A549 cells. Cyclosporine A (CsA), the Cyp-D inhibitor, and Cyp-D silencing were prevented doxorubicin-induced non-apoptotic death of A549 cells, while cells overexpressing Cyp-D were hyper-sensitive to doxorubicin. In A549 cells, doxorubicin-activated p53, the latter translocated to mitochondria and physically interacted with Cyp-D. The p53/Cyp-D mitochondrial complexation was prevented by CsA or Cyp-D silencing, or by p53 inhibitor pifithrin-α. Significantly, doxorubicin-induced anti-tumor ability in vivo was also compromised by CsA, or when Cyp-D was silenced. Together, these data suggested that Dox-induced non-apoptotic death of A549 cells requires mitochondrial Cyp-D-p53 complexation.

Deep learning to estimate lithium-ion battery state of health without additional degradation experiments.

State of health is a critical state which evaluates the degradation level of batteries. However, it cannot be measured directly but requires estimation. While accurate state of health estimation has progressed markedly, the time- and resource-consuming degradation experiments to generate target battery labels hinder the development of state of health estimation methods. In this article, we design a deep-learning framework to enable the estimation of battery state of health in the absence of target battery labels. This framework integrates a swarm of deep neural networks equipped with domain adaptation to produce accurate estimation. We employ 65 commercial batteries from 5 different manufacturers to generate 71,588 samples for cross-validation. The validation results indicate that the proposed framework can ensure absolute errors of less than 3% for 89.4% of samples (less than 5% for 98.9% of samples), with a maximum absolute error of less than 8.87% in the absence of target labels. This work emphasizes the power of deep learning in precluding degradation experiments and highlights the promise of rapid development of battery management algorithms for new-generation batteries using only previous experimental data.

Neutralization against Omicron subvariants after BA.5/BF.7 breakthrough infection weakened as virus evolution and aging despite repeated prototype-based vaccination1.

BACKGROUND: Omicron had swept the mainland China between December 2022 and January 2023, while SARS-CoV-2 still continued to evolve. To fully prepare for the next wave, it's urgent to evaluate the humoral immune response post BA.5/BF.7 breakthrough infection against predominant sub-lineages among existing vaccination strategies and the elders. METHOD: This study enrolled a longitudinal young-adult cohort from 2/3-dose vaccination to 1 month after breakthrough infection, and an elder cohort at 1 month after breakthrough infection. Seral samples were collected and tested for humoral immune response to SARS-CoV-2 subvariants including WT, BA.2, BA.5, BF.7, BQ.1.1, CH.1.1, XBB.1.5. RESULTS: BA.5/BF.7 breakthrough infection induced higher neutralization activity than solely vaccination in all SARS-CoV-2 strains, while the latest Omicron subvariants, BQ.1.1, CH.1.1, XBB.1.5, exhibited the strongest neutralization evasion ability. There was a negative correlation between age and humoral immune response in WT, BA.5, BQ.1.1, and XBB.1.5. Compared to non-vaccination groups, breakthrough infection in two-dose vaccination groups had significantly higher neutralizing antibody against WT, BA.2, BA.5, BF.7 but not to BQ.1.1, CH.1.1, XBB.1.5 while booster dose against the prototype prior-breakthrough would not further significantly enhance individual's humoral responses against the latest Omicron subvariants. CONCLUSIONS: Newer variants manifest increasing immune evasion from neutralization and repeated prototype-based booster vaccines may not further enhance neutralizing antibody against emerging new variants. Older adults have lower levels of neutralizing antibody. Future vaccination strategies should aim to enhance effective neutralization to contemporary variants.

Pembrolizumab monotherapy or combination therapy for bone metastases in advanced non-small cell lung cancer: a real-world retrospective study.

BACKGROUND: The incidence of bone metastases in non-small cell lung cancer (NSCLC) patients is about 30-40% and bone-related events can seriously affect quality of life. Immune checkpoint inhibitor (ICI) therapy has become the standard treatment for advanced NSCLC patients. However, the specific efficacy of ICIs in NSCLC patients with bone metastases remains unclear. The aim of the present study was to explore the prognosis of immunotherapy in this population and to find potential biomarkers. METHODS: In this retrospective study, a total of 110 advanced NSCLC patients with bone metastases who received pembrolizumab therapy were enrolled. Patient characteristics; palliative bone radiotherapy or bone-targeted therapy; serum levels of lactate dehydrogenase (LDH), and the neutrophil-to-lymphocyte ratio (NLR) at baseline were assessed. The correlation of these factors with progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) was analyzed. RESULTS: The ORR of the total population was 29.1%, and PFS and OS were 7.0 and 14.8 months, respectively. Fifty-eight patients (52.7%) received pembrolizumab treatment as first-line therapy, and 52 patients (47.3%) as second-line therapy or beyond [ORR: 41.4% vs. 15.4%, P=0.011; PFS: 9.0 vs. 4.0 months, P=0.004; OS: not reached (NR) vs. 11.5 months, P<0.0001]. Bone therapy, including palliative bone radiotherapy and bone-targeted therapy, increased the ORR (34.9% vs. 11.1%, P<0.0001) and prolonged PFS (8.5 vs. 2.0 months, P=0.002). Eastern Cooperative Oncology Group performance status score of 0-1 [OS: hazard ratio (HR) =0.117, P<0.0001] and first-line pembrolizumab therapy (OS: HR =0.372, P=0.004) were independent predictors of OS. Patients whose baseline serum LDH level was ≤240.5 IU/L (NR vs. 10.0 months, P<0.0001) or NLR ≤5.55 (NR vs. 18.0 months, P=0.039) showed longer OS. CONCLUSIONS: The efficacy of Pembrolizumab therapy is confirmed in advanced NSCLC patients with bone metastases, particularly when palliative bone radiotherapy or bone-targeted therapy is delivered. Baseline serum LDH level ≤240.5 IU/L and NLR ≤5.55 might predict the prognosis of patients with bone metastases from advanced NSCLC treated with immunotherapy.

Aberrant cholesterol metabolic signaling impairs antitumor immunosurveillance through natural killer T cell dysfunction in obese liver.

Obesity is a major risk factor for cancers including hepatocellular carcinoma (HCC) that develops from a background of non-alcoholic fatty liver disease (NAFLD). Hypercholesterolemia is a common comorbidity of obesity. Although cholesterol biosynthesis mainly occurs in the liver, its role in HCC development of obese people remains obscure. Using high-fat high-carbohydrate diet-associated orthotopic and spontaneous NAFLD-HCC mouse models, we found that hepatic cholesterol accumulation in obesity selectively suppressed natural killer T (NKT) cell-mediated antitumor immunosurveillance. Transcriptome analysis of human liver revealed aberrant cholesterol metabolism and NKT cell dysfunction in NAFLD patients. Notably, cholesterol-lowering rosuvastatin restored NKT expansion and cytotoxicity to prevent obesogenic diet-promoted HCC development. Moreover, suppression of hepatic cholesterol biosynthesis by a mammalian target of rapamycin (mTOR) inhibitor vistusertib preceded tumor regression, which was abolished by NKT inactivation but not CD8+ T cell depletion. Mechanistically, sterol regulatory element-binding protein 2 (SREBP2)-driven excessive cholesterol production from hepatocytes induced lipid peroxide accumulation and deficient cytotoxicity in NKT cells, which were supported by findings in people with obesity, NAFLD and NAFLD-HCC. This study highlights mTORC1/SREBP2/cholesterol-mediated NKT dysfunction in the tumor-promoting NAFLD liver microenvironment, providing intervention strategies that invigorating NKT cells to control HCC in the obesity epidemic.

Epidermal Growth Factor Receptor Mutation Status and Response to Tyrosine Kinase Inhibitors in Advanced Chinese Female Lung Squamous Cell Carcinoma: A Retrospective Study.

BACKGROUND: The frequency of epidermal growth factor receptor (EGFR) mutations and the efficacy of tyrosine kinase inhibitor (TKI) in Chinese female patients with lung squamous cell carcinoma (SCC) are unknown. This study was designed to investigate the incidence of EGFR mutations and the role of targeted therapy in advanced Chinese female lung SCC patients. METHODS: Advanced female patients diagnosed with lung SCC at the Shanghai Chest Hospital between January 2013 and December 2018 were retrospectively analyzed. RESULTS: A total of 4223 advanced lung SCC patients were screened, and there were 154 female lung SCC patients who had underwent EGFR mutation detection. Positive EGFR mutations were found in 29.9% (46/154) of female lung SCC patients, including twenty-three 19del mutation (14.9%), twenty-one 21L858R mutation (13.6%) and other mutations (1.4%, 21861Q and 20ins). For 45 EGFR positive mutation female SCC patients, the median progression-free survival (PFS) of patients who received EGFR-TKI therapy (n=38) was 8.0 months (95% CI, 5.4-10.7 months), which was significantly longer than patients who were treated with chemotherapy (8.0 vs. 3.2 months, p=0.024), and the median overall survival (OS) was also longer (24.9 months vs. 13.9 months, p=0.020). The objective response rate (ORR) was 44.7% (17/38), and the disease control rate (DCR) was 81.6% (31/38). For 105 female SCC patients with EGFR negative mutation, the median OS was 18.6 months (95% CI, 14.2-22.9 months) and it was no different from that of EGFR positive mutation patients (18.6 vs. 22.8 months, p=0.377). CONCLUSION: For advanced Chinese female lung SCC patients with EGFR positive mutations, targeted therapy could confer longer PFS and OS than chemotherapy, but the survival was similar with patients who were negative EGFR mutations.

The lncRNA XIST/miR-125b-2-3p axis modulates cell proliferation and chemotherapeutic sensitivity via targeting Wee1 in colorectal cancer.

BACKGROUND: Numerous reports on microRNAs have illustrated their role in tumor growth and metastasis. Recently, a new prognostic factor, miR-125b-2-3p, has been identified for predicting chemotherapeutic sensitivity in advanced colorectal cancer (CRC). However, the specific mechanisms and biological functions of miR-125b-2-3p in advanced CRC under chemotherapy have yet to be elucidated. METHODS: MiR-125b-2-3p expression was detected by real-time PCR (RT-PCR) in CRC tissues. The effects of miR-125b-2-3p on the growth, metastasis, and drug sensitivity of CRC cells were tested in vitro and in vivo. Based on multiple databases, the upstream competitive endogenous RNAs (ceRNAs) and the downstream genes for miR-125b-2-3p were predicted by bioinformatic analysis, followed by the experiments including luciferase reporter assays, western blot assays, and so on. RESULTS: MiR-125b-2-3p was significantly lowly expressed in the tissues and cell lines of CRC. Higher expression of miR-125b-2-3p was associated with relatively lower proliferation rates and fewer metastases. Moreover, overexpressed miR-125b-2-3p remarkably improved chemotherapeutic sensitivity of CRC in vivo and in vitro. Mechanistically, miR-125b-2-3p was absorbed by long noncoding RNA (lncRNA) XIST regulating WEE1 G2 checkpoint kinase (WEE1) expression. The upregulation of miR-125b-2-3p inhibited the proliferation and epithelial-mesenchymal transition (EMT) of CRC induced by lncRNA XIST. CONCLUSIONS: Lower miR-125b-2-3p expression resulted in lower sensitivity of CRC to chemotherapy and was correlated with poorer survival of CRC patients. LncRNA XIST promoted CRC metastasis acting as a ceRNA for miR-125b-2-3p to mediate WEE1 expression. LncRNA XIST-miR-125b-2-3p-WEE1 axis not only regulated CRC growth and metastasis but also contributed to chemotherapeutic resistance to CRC.

Sentiment analysis for e-commerce product reviews by deep learning model of Bert-BiGRU-Softmax.

Sentiment analysis of e-commerce reviews is the hot topic in the e-commerce product quality management, from which manufacturers are able to learn the public sentiment about products being sold on e-commerce websites. Meanwhile, customers can know other people's attitudes about the same products. This paper proposes the deep learning model of Bert-BiGRU-Softmax with hybrid masking, review extraction and attention mechanism, which applies sentiment Bert model as the input layer to extract multi-dimensional product feature from e-commerce reviews, Bidirectional GRU model as the hidden layer to obtain semantic codes and calculate sentiment weights of reviews, and Softmax with attention mechanism as the output layer to classify the positive or negative nuance. A series of experiments are conducted on the large-scale dataset involving over 500 thousand product reviews. The results show that the proposed model outperforms the other deep learning models, including RNN, BiGRU, and Bert-BiLSTM, which can reach over 95.5% of accuracy and retain a lower loss for the e-commerce reviews.

Prognostic value of the serum apolipoprotein B to apolipoprotein A-I ratio in metastatic colorectal cancer patients.

Background: The aim of our research was to assess the prognostic value of the apolipoprotein B (ApoB) to apolipoprotein A-I (ApoA-I) ratio (ApoB/ApoA-I) in metastatic colorectal cancer (mCRC) patients. Methods: We randomly assigned 838 patients into the training cohort (n=578) and the validation cohort (n=260). The cut-off value of the ApoB/ApoA-I in the training cohort identified by a receiver operating characteristic (ROC) curve was 0.69 and was further validated in the validation cohort. A propensity score matching (PSM) analysis was carried out to eliminate the imbalance in the baseline characteristics of the high and low ApoB/ApoA-I group. The PSM cohort of 542 mCRC patients was generated. We also validated our main findings and conclusions with an independent cohort (n=150). Univariate and multivariate analyses were conducted to explore the independent prognostic value of the ApoB/ApoA-I in the training cohort (n=578), the validation cohort (n=260), the PSM cohort (n=542) and the independent cohort (n=150). Results: Patients in the high ApoB/ApoA-I group had significantly shorter overall survival compared to those in the low ApoB/ApoA-I group in the training cohort, the validation cohort, the PSM cohort and the independent cohort (P <0.01). Multivariate analysis indicated that the ApoB/ApoA-I was an independent prognostic index for OS in the training cohort [hazard ratio (HR):1.371; 95% confidence interval (CI):1.205-1.870, P=0.045], the validation cohort (HR: 1.924; 95% CI: 1.360-2.723, P<0.001), the PSM cohort (HR: 1.599; 95% CI: 1.287-1.988, P<0.001) and the independent cohort (HR: 1.949; 95% CI: 1.014-3.747, P=0.046). Conclusions: An increased baseline serum ApoB/ApoA-I is an independent prognostic factor for a poor prognosis in mCRC patients.

METTL3 Promotes the Progression of Gastric Cancer via Targeting the MYC Pathway.

Methyltransferase-like 3 (METTL3), a major component of the N6-methyladenosine (m6A) methyltransferase complex, has been suggested to function as an oncogene in several cancers. However, its biological mechanism and the involved pathways in gastric cancer (GC) remain unknown. Here, we reported that frequent upregulation of METTL3 was responsible for the aberrant m6A levels in gastric carcinoma. On the other hand, a high level of METTL3 was significantly associated with several clinicopathological features and poor survival in patients with GC. The knockdown of METTL3 effectively inhibited cell proliferation and migration and invasion capacity. Moreover, overexpression of METTL3 considerably augmented its oncogenic function. Integrated RNA-seq and m6A-seq analysis first indicated that several component molecules (e.g., MCM5, MCM6, etc.) of MYC target genes were mediated by METTL3 via altered m6A modification. Our work uncovers the oncogenic roles of METTL3 in GC and suggests a critical mechanism of GC progression.

Inhibition of fatty acid catabolism augments the efficacy of oxaliplatin-based chemotherapy in gastrointestinal cancers.

Gastrointestinal cancer causes countless deaths every year due to therapeutic resistance. However, whether metabolic alterations contribute to chemoresistance is not well understood. In this study, we report that fatty acid (FA) catabolism was activated in gastrointestinal cancer cells treated with oxaliplatin, which exhibited higher expression of the rate-limiting enzymes carnitine palmitoyltransferase 1B (CPT1B) and CPT2. The clinical analysis also showed that high expression of these enzymes was associated with poor oxaliplatin-based chemotherapy outcomes in patients. Furthermore, genetic or pharmacological inhibition of CPT2 with perhexiline disturbed NADPH and redox homeostasis and increased reactive oxygen species (ROS) generation and cell apoptosis in gastrointestinal cancer cells following oxaliplatin treatment. Specifically, the combination of oxaliplatin and perhexiline significantly suppressed the progression of gastrointestinal cancer in cell-based xenograft and patient-derived xenograft (PDX) models. Mechanistically, CPT2 was transcriptionally upregulated by nuclear factor of activated T cells 3 (NFATc3), which translocated to the nucleus in response to oxaliplatin treatment. In summary, our study suggests that the inhibition of CPT-mediated FA catabolism combined with conventional chemotherapy is a promising therapeutic strategy for patients with gastrointestinal cancers.

Establishment of Gastric Cancer Patient-derived Xenograft Models and Primary Cell Lines.

The use of preclinical models to advance our understanding of tumor biology and investigate the efficacy of therapeutic agents is key to cancer research. Although there are many established gastric cancer cell lines and many conventional transgenic mouse models for preclinical research, the disadvantages of these in vitro and in vivo models limit their applications. Because the characteristics of these models have changed in culture, they no longer model tumor heterogeneity, and their responses have not been able to predict responses in humans. Thus, alternative models that better represent tumor heterogeneity are being developed. Patient-derived xenograft (PDX) models preserve the histologic appearance of cancer cells, retain intratumoral heterogeneity, and better reflect the relevant human components of the tumor microenvironment. However, it usually takes 4-8 months to develop a PDX model, which is longer than the expected survival of many gastric patients. For this reason, establishing primary cancer cell lines may be an effective complementary method for drug response studies. The current protocol describes methods to establish PDX models and primary cancer cell lines from surgical gastric cancer samples. These methods provide a useful tool for drug development and cancer biology research.

Eukaryotic initiation factor 4A2 promotes experimental metastasis and oxaliplatin resistance in colorectal cancer.

BACKGROUND: Deregulation of protein translation control is a hallmark of cancers. Eukaryotic initiation factor 4A2 (EIF4A2) is required for mRNA binding to ribosome and plays an important role in translation initiation. However, little is known about its functions in colorectal cancer (CRC). METHODS: Analysis of CRC transcriptome data from TCGA identified that EIF4A2 was associated with poor prognosis. Immunohistochemistry study of EIF4A2 was carried out in 297 paired colorectal tumor and adjacent normal tissue samples. In vitro and in vivo cell-biological assays were performed to study the biological functions of EIF4A2 on experimental metastasis and sensitivity to oxaliplatin treatment. Bioinformatic prediction, chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assay were carried out to unveil the transcription factor of EIF4A2 regulation. RESULTS: EIF4A2 Expression is significantly higher in colorectal tumors. Multivariate analysis suggests EIF4A2 as an independent predictor of overall, disease-free and progression-free survival. Dysfunction of EIF4A2 by genetic knock-down or small-molecule inhibitor silvestrol dramatically inhibited CRC invasion and migration, sphere formation and enhanced sensitivity to oxaliplatin treatment in vitro and in vivo. Notably, EIF4A2 knock-down also suppressed lung metastasis in vivo. qRT-PCR and immunoblotting analyses identified c-Myc as a downstream target and effector of EIF4A2. ChIP and dual-luciferase reporter assays validated the bioinformatical prediction of ZNF143 as a specific transcription factor of EIF4A2. CONCLUSIONS: EIF4A2 promotes experimental metastasis and oxaliplatin resistance in CRC. Silvestrol inhibits tumor growth and has synergistic effects with oxaliplatin to induce apoptosis in cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models.