DNA demethylase TET2-mediated reduction of HADHB expression contributes to cadmium-induced malignant progression of colorectal cancer.

Environmental exposure to the cadmium (Cd) has been shown to be a risk factor for colorectal cancer (CRC) progression, but the exact mechanism has not been fully elucidated. In this study, we found that chronic Cd (3 µM) exposure promoted the proliferation, adhesion, migration, and invasion of CRC cells in vitro, as well as lung metastasis in vivo. RNA-seq and TCGA-COAD datasets revealed that decreased hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit beta (HADHB) expression may be a crucial factor in Cd-induced CRC progression. Further analysis using qRT-PCR and tissue microarrays from CRC patients showed that HADHB expression was significantly reduced in CRC tissues compared to adjacent normal tissues, and low HADHB expression was associated with adverse clinical features and poor overall survival, either directly or through TNM stage. Furthermore, HADHB was found to play an important role in the Cd-induced malignant metastatic phenotype of CRC cells and lung metastasis in mice. Mechanistically, we discovered that chronic Cd exposure resulted in hypermethylation of the HADHB promoter region via inhibition of DNA demethylase tet methylcytosine dioxygenase 2 (TET2), which then led to decreased HADHB expression and activation of the FAK signaling pathway, and ultimately contributed to CRC progression. In conclusion, this study provided a new potential insight and evaluable biomarker for Cd exposure-induced CRC progression and treatment.

TSPO deficiency exacerbates acute lung injury via NLRP3 inflammasome-mediated pyroptosis.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a common cause of respiratory failure in many critically ill patients. Although inflammasome activation plays an important role in the induction of acute lung injury (ALI) and ARDS, the regulatory mechanism of this process is still unclear. When cells are stimulated by inflammation, the integrity and physiological function of mitochondria play a crucial part in pyroptosis. However, the underlying mechanisms and function of mitochondrial proteins in the process of pyroptosis are largely not yet known. Here, we identified the 18-kDa translocator protein (TSPO), a mitochondrial outer membrane protein, as an important mediator regulating nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing protein 3 (NLRP3) inflammasome activation in macrophages during ALI. METHODS: TSPO gene knockout (KO) and lipopolysaccharide (LPS)-induced ALI/ARDS mouse models were employed to investigate the biological role of TSPO in the pathogenesis of ARDS. Murine macrophages were used to further characterize the effect of TSPO on the NLRP3 inflammasome pathway. Activation of NLRP3 inflammasome was preformed through LPS + adenosine triphosphate (ATP) co-stimulation, followed by detection of mitochondrial membrane potential, reactive oxygen species (ROS) production, and cell death to evaluate the potential biological function of TSPO. Comparisons between two groups were performed with a two-sided unpaired t -test. RESULTS: TSPO- KO mice exhibited more severe pulmonary inflammation in response to LPS-induced ALI. TSPO deficiency resulted in enhanced activation of the NLRP3 inflammasome pathway, promoting more proinflammatory cytokine production of macrophages in LPS-injured lung tissue, including interleukin (IL)-1ß, IL-18, and macrophage inflammatory protein (MIP)-2. Mitochondria in TSPO -KO macrophages tended to depolarize in response to cellular stress. The increased production of mitochondrial damage-associated molecular pattern led to enhanced mitochondrial membrane depolarization and pyroptosis in TSPO -KO cells. CONCLUSION: TSPO may be the key regulator of cellular pyroptosis, and it plays a vital protective role in ARDS occurrence and development.

Prediction of anti-cancer drug synergy based on cross-matching network and cancer molecular subtypes.

At present, anti-cancer drug synergy therapy is one of the most important methods to overcome drug resistance and reduce drug toxicity in cancer treatment. High-throughput screening through deep learning can effectively improve the efficiency of discovering synergistic drugs. Nowadays, most of the existing deep learning algorithms for anti-cancer drug synergy prediction use deep neural networks and can only implicitly perform feature interaction. This study proposes a deep learning algorithm, named MolCross, which combines implicit feature interaction with explicit features to improve the accuracy of prediction of the anti-cancer drug synergy score. MolCross uses a deep autoencoder to extract features from high-dimensional input, uses the drug-specific subnetworks and cross-network to perform implicit feature interaction and explicit feature interaction respectively, and finally uses a synergy prediction network to combine the two feature interaction methods to obtain the final prediction results. We adopted a five-fold cross validation and compared MolCross with other four anti-cancer drug synergy prediction models. The results show that MolCross has better prediction performance than other models. MolCross also has good performance in terms of cross-cell line and cross-tissue type. Existing studies have demonstrated that cancer molecular subtypes have different sensitivities to targeted therapy. In this study, the features of cancer molecular subtype were introduced in the model using an embedding layer in MolCross to explore the effect of cancer molecular subtype on anti-cancer drug synergy. We also found that the cancer molecular subtype is one of the main factors affecting the synergy between drugs.

Nicotine-derived NNK promotes CRC progression through activating TMUB1/AKT pathway in METTL14/YTHDF2-mediated m6A manner.

Cigarette smoking substantially promotes tumorigenesis and progression of colorectal cancer; however, the underlying molecular mechanism remains unclear. Among 662 colorectal cancer patients, our investigation revealed a significant correlation between cigarette smoking and factors, such as large tumor size, poor differentiation, and high degree of invasion. Among the nicotine-derived nitrosamines, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) emerged as the most critical carcinogen, which significantly promoted the malignant progression of colorectal cancer both in vivo and in vitro. The results of methylated RNA immunoprecipitation and transcriptome sequencing indicated that NNK upregulated transmembrane and ubiquitin-like domain-containing protein 1 (TMUB1) via N6-adenosine methylation, which was regulated by methyltransferase-like 14 (METTL14) and YTH N6-methyladenosine RNA binding protein 2 (YTHDF2). Elevated TMUB1 levels were associated with a higher risk of cancer invasion and metastasis, leading to a high mortality risk in patients with colorectal cancer. Additionally, TMUB1 promoted lysine63-linked ubiquitination of AKT by interacting with AMFR, which led to the induction of malignant proliferation and metastasis in colorectal cancer cells exposed to NNK. In summary, this study provides a new insight, indicating that targeting TMUB1 expression via METTL14/YTHDF2 mediated N6-adenosine methylation may be a potential therapeutic and prognostic target for patients with colorectal cancer who smoke.

Anti-PD-1 antibody armored γδ T cells enhance anti-tumor efficacy in ovarian cancer.

γδ T cells have the unique ability to detect a wide range of tumors with low mutation burdens, making them attractive candidates for CAR-T-cell therapy. Unlike αß T cells and other immune cells, γδ T cells are superior in MHC non-restriction, selective cell recruitment, and rapid activation. However, clinical trials have shown limited clinical benefits, and the adoptive transplantation of γδ T cells has often fallen short of expectations. We hypothesized that the limited effectiveness of γδ T cells in eradicating tumor cells may be attributed to the inhibitory tumor microenvironment induced by the suppressive PD-1/PD-L1 axis. Herein, we constructed novel armored γδ T cells capable of secreting humanized anti-PD-1 antibodies, referred to as "Lv-PD1-γδ T cells. Lv-PD1-γδ T cells showed improved proliferation and enhanced cytotoxicity against tumor cells, resulting in augmented therapeutic effects and survival benefits in ovarian tumor-bearing mice. These engineered cells demonstrated a prolonged in vivo survival of more than 29 days, without any potential for tumorigenicity in immunodeficient NOD/SCID/γ null mice. We also found that Lv-PD1-γδ T cells exhibited excellent tolerance and safety in humanized NOD/SCID/γ null mice. With attenuated or eliminated immunosuppression and maximized cytotoxicity efficacy by the local secretion of anti-PD1 antibodies in tumors, Lv-PD1-γδ T cells can serve as a promising "off-the-shelf" cell therapy against cancers.

Risk Factors of Demoralization Among Lung Cancer Patients in Mainland China.

Objectives: Due to the severity of cancer, patients may experience feelings of helplessness and despair, resulting in demoralization among lung cancer patients. In this study, we investigated the risk factors of demoralization in middle-aged and older Chinese lung cancer patients via their relationship with patients' demographic data and disease characteristics. Methods: This study is a cross-sectional descriptive study using a structured questionnaire including assessments of demographic data and disease, the Demoralization Scale Mandarin Version (DS-MV), the Social Support Rate Scale (SSRS), the Medical Coping Modes Questionnaire (MCMQ), as well as The European Organization for Research and Treatment of Cancer (EORTC QLQ-C30). Results: Overall, 289/300 (96.3%) patients with lung cancer completed questionnaires. The mean score of DS-MV was 49.27 (SD=15.19) (range, 21-81) and the mean score of SSRS was 33.37 (SD=5.43) (range,17-48). Multiple linear regression analysis identified high demoralization was significantly related to age (p<.001), medical payment (p=.003), times of chemotherapy (p=.026), family monthly income (p=.025), avoidance dimension (p<.001), surrender dimension (p<.001), social support (p=.001), symptom score (p<.001), overall health score (p=.009) and function score (p<.001). Conclusion: This study demonstrates the factors influencing demoralization among middle-aged and older lung cancer patients. Demoralization is a prevalent psychiatric problem in Chinese lung cancer patients. Therefore, we recommend strong social support to be protective against demoralization. We suggest that medical staff establish the concept of social support for patients with lung cancer, actively seek effective resources from family, friends, and other social support organizations to help patients establish a social support system that improves patient courage and confidence in their post-cancer life.

Landscape of internal N7-methylguanosine of long non-coding RNA modifications in resistant acute myeloid leukemia.

BACKGROUND: Growing evidence indicates that RNA methylation plays a fundamental role in epigenetic regulation, which is associated with the tumorigenesis and drug resistance. Among them, acute myeloid leukemia (AML), as the top acute leukemia for adults, is a deadly disease threatening human health. Although N7-methylguanosine (m7G) has been identified as an important regulatory modification, its distribution has still remained elusive. METHODS: The present study aimed to explore the long non-coding RNA (lncRNA) functional profile of m7G in AML and drug-resistant AML cells. The transcriptome-wide m7G methylation of lncRNA was analyzed in AML and drug-resistant AML cells. RNA MeRIP-seq was performed to identify m7G peaks on lncRNA and differences in m7G distribution between AML and drug-resistant AML cells. The Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted to predict the possible roles and m7G-associated pathway. RESULTS: Using m7G peak sequencing, it was found that a sequence motif was necessary for m7G methylation in drug-resistant AML lncRNA. Unsupervised hierarchical cluster analysis confirmed that lncRNA m7G methylation occurred more frequently in drug-resistant AML cells than in AML cells. RNA sequencing demonstrated that more genes were upregulated by methylation in drug-resistant AML cells, while methylation downregulated more genes in AML cells. The GO and KEGG pathway enrichment analyses revealed that genes having a significant correlation with m7G sites in lncRNA were involved in drug-resistant AML signaling pathways. CONCLUSION: Significant differences in the levels and patterns of m7G methylation between drug-resistant AML cells and AML cells were revealed. Furthermore, the cellular functions potentially influenced by m7G in drug-resistant AML cells were predicted, providing evidence implicating m7G-mediated lncRNA epigenetic regulation in the progression of drug resistance in AML. These findings highlight the involvement of m7G in the development of drug resistance in AML.

EIF4A3 Acts on the PI3K-AKT-ERK1/2-P70S6K Pathway through FLOT1 to Influence the Development of Lung Adenocarcinoma.

Lung adenocarcinoma (LUAD) is a major lung cancer subtype. In this study, we discovered that the eukaryotic translation initiation factor EIF4A3 expression was significantly higher in LUAD tissues and that this higher expression was closely linked to a poor prognosis for LUAD. In addition, we demonstrated that the knockdown of EIF4A3 significantly inhibited the proliferation, invasion, and migration of LUAD cells in vitro and in vivo. The findings of mass spectrometry analysis revealed that EIF4A3 could interact with Flotillin-1 in LUAD cells and that EIF4A3 could positively regulate the expression of FLOT1 at the protein level. Meanwhile, transcriptome sequencing showed that EIF4A3 could influence the development of LUAD by affecting PI3K-AKT-ERK1/2-P70S6K and PI3K class III-mediated autophagy in the Apelin pathway. In addition, we confirmed that Flotillin-1 expression was upregulated in LUAD based on the existing literature, and knockdown of FLOT1 could inhibit the proliferation and migration of LUAD cells. In addition, the knockdown of Flotillin-1 reversed the increase of cell proliferation and migration caused by EIF4A3 overexpression. Furthermore, we found that the activation of PI3K-AKT-ERK1/2-P70S6K signaling pathway and PI3K class III-mediated autophagy caused by EIF4A3 overexpression was rescued by the knockdown of FLOT1. In a word, we proved that EIF4A3 positively regulates the expression of FLOT1 and plays a procancer role in LUAD. IMPLICATIONS: Our study revealed the role of EIF4A3 in prognosis and tumor progression in LUAD, indicating that EIF4A3 could be used as the molecular diagnostic and prognostic therapeutic target.

Unveiling the role of defects in iron oxyhydroxide for oxygen evolution.

Development of earth-abundant and robust oxygen evolution reaction (OER) catalysts is imperative for cost-effective hydrogen production via water electrolysis. Herein, we report ultrafine iron (oxy)hydroxide nanoparticles with average particle size of 2.6 nm and abundant surface defects homogeneously supported on oleum-treated graphite (FeOx(n)@HG-T), providing abundant active sites for the OER. The optimal FeOx(0.03)@HG-110 exhibits high electrocatalytic OER activity and excellent stability. Electrochemical testing results and theoretical calculations reveal that the outstanding OER activity of FeOx(0.03)@HG-110 is due to its stronger charge transfer ability and lower OER energy barrier than defect-free FeOx nanoparticles. This work demonstrates that the OER performance of oxyhydroxide-based electrocatalysts can be improved by surface defect engineering.

Effects of Neoadjuvant Radiotherapy on Survival in Patients with Stage IIIA-N2 Non-Small-Cell Lung Cancer Following Pneumonectomy.

Background: Pneumonectomy is a drastic but sometimes inevitable treatment option for patients with non-small-cell lung cancer (NSCLC) to improve their chances for long-term survival. However, the optimal adjuvant radiotherapy used for patients with N2 NSCLC following pneumonectomy remains unclear in the literature. Methods: T1-4N0-2M0 NSCLC patients registered in the Surveillance, Epidemiology, and End Results database were retrospectively analyzed. Propensity score matching was applied to balance the assignment of patients. Cox proportional hazards models and Kaplan−Meier analyses were used to identify the factors related to overall survival rates. Restricted cubic splines were used to detect the possible nonlinear dependency of the relationship between the risk of survival and age. Results: A total of 4308 NSCLC patients were enrolled in this study. In N2 patients, the long-term outcome of the chemotherapy and postoperative radiotherapy groups was the worst (p = 0.014). Subgroup analyses showed that the influence of age on survival outcome was confined to patients who received chemotherapy and neoadjuvant radiotherapy (p = 0.004). Meanwhile, patients >65 years of age who received chemotherapy and neoadjuvant radiotherapy had significantly worse prognoses than those in the chemotherapy group (p = 0.005). Conclusions: Our results show that neoadjuvant radiotherapy may have potential benefits in patients aged ≤ 65 years who are scheduled for pneumonectomy, but not in elderly patients.

Comparison of the perioperative outcomes between robotic-assisted thoracic surgery and video-assisted thoracic surgery in non-small cell lung cancer patients with different body mass index ranges.

Background: Non-small cell lung cancer (NSCLC) is the most common malignancy and one of the most common causes of cancer-related death worldwide. Robotic-assisted thoracic surgery (RATS) has gradually become a prevalent surgical method for patients with NSCLC. Previous studies have found that body mass index (BMI) is associated with postoperative outcomes. This study aimed to investigate the effectiveness of RATS compared to video-assisted thoracic surgery (VATS) in the treatment of NSCLC with different BMI, in terms of perioperative outcomes. Methods: The baseline and perioperative data, including BMI, of 849 NSCLC patients who underwent minimally invasive anatomic lung resections from August 2020 to April 2021 were retrospectively collected and analyzed. Propensity score matching analysis was applied to minimize potential bias between the two groups (VATS and RATS), and the perioperative outcomes were compared. Subgroup analysis was subsequently performed. Results: Compared to VATS, RATS had more lymph nodes dissected {9 [inter-quartile range (IQR), 6-12] vs. 7 (IQR, 6-10), P<0.001}, a lower estimated bleeding volume [40 (IQR, 30-50) vs. 50 (IQR, 40-60) mL, P<0.001], and other better postoperative outcomes, but a higher cost of hospitalization [¥83,626 (IQR, 77,211-92,686) vs. ¥75,804 (IQR, 66,184-83,693), P<0.001]. Multivariable logistic regression analysis indicated that RATS (P=0.027) and increasing BMI (P=0.030) were associated with a statistically significant reduction in the risk of postoperative complications. Subgroup analysis indicated that the advantages of RATS may be more obvious in patients with a BMI of 24-28 kg/m2, in which the RATS group had more lymph nodes dissected [9 (IQR, 6-12) vs. 7 (IQR, 5-10), P<0.001] and a decreased risk of total postoperative complications [odds ratio (OR), 0.443; 95% confidence interval (CI), 0.212-0.924; P=0.030] compared to the VATS group. Conclusions: Both, RATS and VATS can be safely applied for patients with NSCLC. Perioperative outcome parameters indicate advantages for RATS, however at a higher cost of hospitalization. The advantages of RATS might be more obvious in patients with a BMI of 24-28 kg/m2.

TSPO Deficiency Exacerbates GSDMD-Mediated Macrophage Pyroptosis in Inflammatory Bowel Disease.

BACKGROUND: the 18-kDa translocator protein (TSPO) is a mitochondrial outer membrane protein, and its expression tends to increase in response to inflammatory stimulation, rapidly. However, the role of TSPO in inflammation and pyroptosis is not yet clear. Here, we identified TSPO as a novel key regulator of pyroptosis. (2) Methods: TSPO knockout and DSS induced mouse inflammatory bowel disease (IBD) models were employed to assess the roles of TSPO in the pathogenesis of IBD. Primary peritoneal macrophages from TSPO knockout mice were applied to evaluate the mechanism of TSPO in cell pyroptosis. CONCLUSIONS: in response to inflammatory injury, TSPO expression is rapidly upregulated and provides a protective function against GSDMD-mediated pyroptosis, which helps us better understand the biological role of TSPO and a novel regulatory mechanism of the pyroptosis process.

Let-7b-3p inhibits tumor growth and metastasis by targeting the BRF2-mediated MAPK/ERK pathway in human lung adenocarcinoma.

BACKGROUND: Lung cancer is a malignant tumor with the highest morbidity and mortality rates worldwide, of which lung adenocarcinoma (LUAD) is the most common subtype. Overall, current treatments of LUAD are not satisfactory; therefore, novel targets need to be explored. Let-7b-3p is an important member of the let-7 family of microRNAs (miRNAs), and has not been studied separately in LUAD. This study aimed to investigate the role and molecular mechanism of let-7b-3p in LUAD. METHODS: Herein, let-7b-3p expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and fluorescence in situ hybridization (FISH) assays. MTT, colony formation assay, flow cytometry analysis, wound-healing, Transwell and in vivo experiments were conducted to assess let-7b-3p's function in LUAD. The downstream target TFIIB-related factor 2 (BRF2) was predicted using bioinformatics analyses and confirmed by dual-luciferase reporter assay and rescue experiments. Additionally, BRF2 was found to affect the MAPK/ERK pathway through transcriptome sequencing analysis and western blot (WB) assay. RESULTS: Let-7b-3p is downregulated in LUAD cells and tissue samples and low let-7b-3p expression is correlated with a poor prognosis in LUAD patients. Let-7b-3p suppresses the proliferation and metastasis of LUAD cells both in vivo and in vitro by directly targeting the BRF2-mediated MAPK/ERK pathway. CONCLUSIONS: Let-7b-3p inhibits the development of LUAD and is an ideal novel therapeutic target for the treatment of LUAD.

Oncogenic role of abnormal spindle­like microcephaly­associated protein in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is a common malignant cancer worldwide. It is urgent to explore its underlying molecular mechanism and identify novel diagnostic biomarkers. Abnormal spindle­like microcephaly (ASPM) has recently received considerable attention due to its function in tumor progression. However, its role in LUAD is unclear. The present study aimed to explore the clinical role of ASPM in LUAD. Seven pairs of LUAD and adjacent normal tissues were collected to identify potential LUAD biomarkers using transcriptome sequencing. The association between ASPM expression and LUAD progression was evaluated using bioinformatics analysis and data obtained from clinical specimens. Using small interfering RNA technology, the function of ASPM was analyzed in the LUAD H1299 and A549 cell lines. Transcriptional profiling of ASPM­deficient H1299 cells was then performed to determine the downstream targets of ASPM. Using databases and clinical specimens, it was revealed that ASPM expression was frequently elevated in LUAD tissues, and this upregulation was highly associated with LUAD progression. ASPM served as an oncogenic regulator of LUAD cell proliferation and metastasis. Mechanistically, ASPM facilitated epithelial­mesenchymal transition (EMT) via the PI3K/AKT signaling pathway and 740 Y­P, an activator of this pathway, restored the migratory ability of ASPM­knockdown LUAD cells. The current study identified ASPM as an independent prognostic biomarker of LUAD that served an important oncogenic role in regulating LUAD cell metastasis by promoting EMT via the PI3K/AKT signaling pathway. Targeting ASPM may therefore be a therapeutic strategy for treating LUAD.

Mex3a promotes oncogenesis through the RAP1/MAPK signaling pathway in colorectal cancer and is inhibited by hsa-miR-6887-3p.

BACKGROUND: Although Mex3 RNA-binding family member A (Mex3a) has demonstrated an important role in multiple cancers, its role and regulatory mechanism in CRC is unclear. In this study, we aimed to investigate the role and clinical significance of Mex3a in CRC and to explore its underlying mechanism. METHODS: Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to detect the expression levels of genes. 5-Ethynyl-2'-deoxyuridine (EDU) and transwell assays were utilized to examine CRC cell proliferation and metastatic ability. The R software was used to do hierarchical clustering analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Overexpression and rescue experiments which included U0126, a specific mitogen activated protein kinase kinase/extracellular regulated protein kinase (MEK/ERK) inhibitor, and PX-478, a hypoxia-inducible factor 1 subunit alpha (HIF-1α) inhibitor, were used to study the molecular mechanisms of Mex3a in CRC cells. Co-immunoprecipitation (Co-IP) assay was performed to detect the interaction between two proteins. Bioinformatics analysis including available public database and Starbase software (starbase.sysu.edu.cn) were used to evaluate the expression and prognostic significance of genes. TargetScan (www.targetscan.org) and the miRDB (mirdb.org) website were used to predict the combination site between microRNA and target mRNA. BALB/c nude mice were used to study the function of Mex3a and hsa-miR-6887-3p in vivo. RESULTS: Clinicopathological and immunohistochemical (IHC) studies of 101 CRC tissues and 79 normal tissues demonstrated that Mex3a was a significant prognostic factor for overall survival (OS) in CRC patients. Mex3a knockdown substantially inhibited the migration, invasion, and proliferation of CRC cells. Transcriptome analysis and mechanism verification showed that Mex3a regulated the RAP1 GTPase activating protein (RAP1GAP)/MEK/ERK/HIF-1α pathway. Furthermore, RAP1GAP was identified to interact with Mex3a in Co-IP experiments. Bioinformatics and dual-luciferase reporter experiments revealed that hsa-miR-6887-3p could bind to the 3'-untranslated regions (3'-UTR) of the Mex3a mRNA. hsa-miR-6887-3p downregulated Mex3a expression and inhibited the tumorigenesis of CRC both in vitro and in vivo. CONCLUSIONS: Our study demonstrated that the hsa-miR-6887-3p/Mex3a/RAP1GAP signaling axis was a key regulator of CRC and Mex3a has the potential to be a new diagnostic marker and treatment target for CRC.

Platelet Count is Associated with the Rate of Lymph Node Metastasis in Lung Adenocarcinoma.

PURPOSE: Emerging studies have revealed that platelets are involved in tumor metastasis in lung adenocarcinoma (ADC). The solid pathological subtype of lung ADC is associated with metastasis, recurrence, and poor prognosis. However, there is no study exploring the relationship between platelets and different lung pathological subtypes. PATIENTS AND METHODS: The association between platelet counts and lymph node metastasis was analyzed in 852 patients with lung ADC who underwent surgery and lymph node dissection. Multivariate logistic analysis was conducted to identify the risk factors of lymph node metastasis. Then, lymph node metastasis and other factors were analyzed to determine their correlation with platelet count and histological subtype. RESULTS: We found that the platelet count was associated with lymph node metastasis (P = 0.01) in multivariable analysis, independent of tumor size, predominant subtype, visceral pleural invasion, and microvessel invasion. In patients with a platelet count ≥300 × 109/L, the rate of lymph node metastasis was 38.5%, almost twice as high as that in patients with a platelet count <300 × 109/L (23.2%). Additionally, elevated platelet counts, even those within the normal range, were significantly associated with a higher rate of lymph node metastasis. The mean platelet count in patients with solid-predominant histology (269.70 ± 69.38 × 109/L) was significantly higher than that in patients with other histologies (P < 0.001). CONCLUSION: Elevated platelet counts are significantly associated with a higher rate of lymph node metastasis, even if the platelet counts are within the reference range. Platelet counts were significantly higher in patients with solid-predominant histology than in patients with other histologies. In addition, VEGF-C may play an important role in lymphatic metastasis in patients with lung ADC. We hypothesize that antiplatelet therapy may reduce lymph node metastasis in lung ADC patients.

Mex3a interacts with LAMA2 to promote lung adenocarcinoma metastasis via PI3K/AKT pathway.

Lung adenocarcinoma (LUAD) is the main subtype of lung cancer. In this study, we found that RBP Mex3a was significantly upregulated in LUAD tissues and elevated Mex3a expression was associated with poor LUAD prognosis and metastasis. Furthermore, we demonstrated that Mex3a knockdown significantly inhibited LUAD cell migration and invasion in vitro and metastasis in nude mice. Transcriptome sequencing indicated that Mex3a affected gene expression linked to ECM-receptor interactions, including laminin subunit alpha 2(LAMA2). RNA immunoprecipitation (RIP) assay revealed Mex3a directly bound to LAMA2 mRNA and Mex3a increased the instability of LAMA2 mRNA in LUAD cells. Furthermore, we discovered that LAMA2 was surprisingly downregulated in LUAD and inhibited LUAD metastasis. LAMA2 knockdown partially reverse the decrease of cell migration and invasion caused by Mex3a knockdown. In addition, we found that both Mex3a and LAMA2 could influence PI3K-AKT pathway, which are downstream effectors of the ECM-receptor pathway. Moreover, the reduced activation of PI3K-AKT pathway in caused by Mex3a depletion was rescued by LAMA2 knockdown. In conclusion, we demonstrated that Mex3a downregulates LAMA2 expression to exert a prometastatic role in LUAD. Our study revealed the prognostic and prometastatic effects of Mex3a in LUAD, suggesting that Mex3a can serve as a prognostic biomarker and a target for metastatic therapy.

Novel long non-coding RNA LINC02323 promotes epithelial-mesenchymal transition and metastasis via sponging miR-1343-3p in lung adenocarcinoma.

BACKGROUND: We have previously developed a unique metastasis-associated signature consisting of six long non-coding RNAs (lncRNAs), including a novel lncRNA, namely LINC02323. In the present study, we aimed to investigate the underlying roles of LINC02323 in the migration, invasion and TGF-ß-induced epithelial-mesenchymal transition (EMT) of lung adenocarcinoma (LUAD) cells. METHODS: The distribution of LINC02323 was detected by the nuclear-plasma separation experiment. Cell proliferation was assessd by MTT assay, and cell migration and invation were detected by transwell assays. EMT was detected by RT-qPCR and western blotting. Interaction between miRNA and LINC02323 was predicted by starBase v2.0 and confirmed by the double luciferase reporting system. RESULTS: LINC02323 was distributed in the cytoplasm and nucleus. The overexpression or deletion of LINC02323 did not affect the proliferation of LUAD cells, while significantly affected the migration and invasion of LUAD cells. TGF-ß-induced EMT process was significantly affected by both RNA interference (RNAi) and overexpression of LINC02323. The predicted results showed that there were binding sites between LINC02323 and miR-1343-3p. The expression of LINC02323 was found to be negatively correlated with miR-1343-3p in LUAD by analyzing The Cancer Genome Atlas (TCGA) database. The double luciferase reporting system, RT-qPCR and western blotting experiments confirmed that LINC02323 could bind to miR-1343-3p, which bound to TGF-ß receptor 1 (TGFBR1). Inhibition of miR-1343-3p reversed LINC02323 silencing-mediated suppression of migration, invasion and EMT. CONCLUSIONS: LINC02323 acts as a competing endogenous RNA (ceRNA), which sponged miR-1343-3p to upregulate the TGFBR1 expression and promote the EMT and metastasis in LUAD. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: LINC02323 promotes epithelial-mesenchymal transition and metastasis via sponging miR-1343-3p in lung adenocarcinoma. WHAT THIS STUDY ADDS: LINC02323 is a key molecule in the process of invasion and metastasis of LUAD and might be used as a potential target in metastatic cancer.

Unique metastasis-associated lncRNA signature optimizes prediction of tumor relapse in lung adenocarcinoma.

BACKGROUND: Local relapses and metastases are primary causes of death in lung cancer patients. In the present study, we aimed to develop a prognostic signature based on metastasis-associated lncRNAs in patients with lung adenocarcinoma (LUAD). METHODS: Firstly, the potential metastasis-associated lncRNAs were identified by analyzing high-throughput data from The Cancer Genome Atlas (TCGA), and based on which, an lncRNA signature was constructed for prediction of relapse in LUAD patients using Cox proportional hazards regression analysis. Moreover, the prognostic performance of the lncRNA signature was evaluated using Kaplan-Meier survival analysis, time-dependent receiver operating characteristic (ROC) curve and Cox analysis, respectively. In addition, the potential metastasis-associated function of these six lncRNAs was confirmed by lncRNA over-expression or depletion and in vitro transwell assays in LUAD cells. RESULTS: An lncRNA signature consisting of six most important prognostic factors (LINC01819, ZNF649-AS1, HNF4A-AS1, FAM222A-AS1, LINC02323 and LINC00672) was developed. The signature was an independent predictor for patients' relapse-free survival (RFS), which could provide higher tumor relapse prediction capability compared with the TNM staging system at three years and five years, respectively (P = 0.0209 and P = 0.0468). Furthermore, the combination of this lncRNA signature and TNM stage had better prognostic value than TNM stage alone at three and five years, respectively (P = 0.0006 and P = 0.0096). Additionally, all the lncRNAs of the signature had a regulatory role in the LUAD cell mobility. CONCLUSIONS: This novel six-lncRNA signature had considerable prognostic value for prediction of relapse in LUAD patients. KEY POINTS: Significant findings of the study The unique metastasis-associated lncRNA signature was related to tumor metastasis and prognosis in LUAD patients. What this study adds This signature had considerable prognostic value for prediction of relapse in LUAD patients.

The papain-like cysteine protease CEP1 is involved in programmed cell death and secondary wall thickening during xylem development in Arabidopsis.

Both tracheary elements and fiber cells undergo programmed cell death (PCD) during xylem development. In this study we investigated the role of papain-like cysteine protease CEP1 in PCD in the xylem of Arabidopsis. CEP1 was located in the cell wall of xylem cells, and CEP1 expression levels in inflorescence stems increased during stem maturation. cep1 mutant plants exhibited delayed stem growth and reduced xylem cell number compared to wild-type plants. Transmission electron microscopy demonstrated that organelle degradation was delayed during PCD, and thicker secondary walls were present in fiber cells and tracheary elements of the cep1 mutant. Transcriptional analyses of the maturation stage of the inflorescence stem revealed that genes involved in the biosynthesis of secondary wall components, including cellulose, hemicellulose, and lignin, as well as wood-associated transcriptional factors, were up-regulated in the cep1 mutant. These results suggest that CEP1 is directly involved in the clearing of cellular content during PCD and regulates secondary wall thickening during xylem development.