Prognostic and immunotherapeutic implications of bilirubin metabolism-associated genes in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is a major subtype of non-small-cell lung cancer and accompanies high mortality rates. While the role of bilirubin metabolism in cancer is recognized, its specific impact on LUAD and patient response to immunotherapy needs to be elucidated. This study aimed to develop a prognostic signature of bilirubin metabolism-associated genes (BMAGs) to predict outcomes and efficacy of immunotherapy in LUAD. We analysed gene expression data from The Cancer Genome Atlas (TCGA) to identify survival-related BMAGs and construct a prognostic model in LUAD. The prognostic efficacy of our model was corroborated by employing TCGA-LUAD and five Gene Expression Omnibus datasets, effectively stratifying patients into risk-defined cohorts with marked disparities in survival. The BMAG signature was indeed an independent prognostic determinant, outperforming established clinical parameters. The low-risk group exhibited a more favourable response to immunotherapy, highlighted by increased immune checkpoint expression and immune cell infiltration. Further, somatic mutation profiling differentiated the molecular landscapes of the risk categories. Our screening further identified potential drug candidates preferentially targeting the high-risk group. Our analysis of critical BMAGs showed the tumour-suppressive role of FBP1, highlighting its suppression in LUAD and its inhibitory effects on tumour proliferation, migration and invasion, in addition to its involvement in cell cycle and apoptosis regulation. These findings introduce a potent BMAG-based prognostic indicator and offer valuable insights for prognostication and tailored immunotherapy in LUAD.

HSP70 via HIF-1 α SUMOylation inhibits ferroptosis inducing lung cancer recurrence after insufficient radiofrequency ablation.

Radiofrequency ablation (RFA) is an effective and feasible therapy for lung cancer, but accelerated progression of residual non-small cell lung cancer (NSCLC) after incomplete radiofrequency ablation (RFA) has frequently been reported. A previous study reported that HSP70 and HIF-1α were highly expressed in areas with incomplete RFA. Therefore, we sought to elucidate the regulatory effect of the HIF-1α/HSP70 pathway on lung cancer recurrence after incomplete radiofrequency ablation. In this study, we found that knockdown of HSP70 can reduce sumo 1, sumo 2/3 (marker of SUMOylation) of HIF-1α and inhibit A549 cell proliferation and migration under heat stress conditions (used to simulate incomplete RFA in vitro). We observed that knockdown of HSP70 altered the expression of ferroptosis-related proteins and genes (SLC7A11 and ACSL3), and the RNA-seq results showed that knockdown of HSP70 activated the ferroptosis pathway, further confirming that HSP70 regulates ferroptosis. In summary, HSP70, via HIF-1α SUMOylation, inhibited ferroptosis, inducing lung cancer recurrence after radiofrequency ablation. The study reveals a new direction for further research on therapeutic targets to suppress lung cancer recurrence and provides a theoretical foundation for further clinical studies.

Hsp70 Promotes SUMO of HIF-1α and Promotes Lung Cancer Invasion and Metastasis.

OBJECTIVE: This study aims to investigate the effect of heat shock protein-70 (Hsp70) on epithelial-mesenchymal transition (EMT) of lung cancer cells under heat stimulation and to explore its possible molecular mechanism. METHODS: qRT-PCR and immunohistochemistry assay were used to detect the expression of Hsp70 in lung cancer tissues and adjacent tissues. EdU assay was used to detect the cell activity. The effect of Hsp70 on the migration and invasion of A549 and NCI-H446 cells was detected by the wound-healing assay and Transwell assay. A tumor transplantation animal model was established to detect the effect of overexpression of Hsp70 on proliferation and metastasis of lung cancer cells. Western blot assay was used to detect the effect of thermal stimulation and overexpression of Hsp70 on SUMO modification of HIF-1α. RESULTS: The wound-healing rate of A549 and NCI-H446 cells under Hsp70 stimulation was significantly higher than blank control group. At the same time, the number of cells passing through the membrane increased significantly. Hypodermic tumor transplantation in nude mice proved that knockout Hsp70 can inhibit proliferation and metastasis of lung cancer cells. Thermal stimulation upregulated the expression of Hsp70 and promoted SUMO modification of HIF-1α, ultimately promoting the proliferation and metastasis of lung cancer. Inhibition of Hsp70 reverses the effect of thermal stimulation on lung cancer by reducing the SUMO modification of HIF-1α. CONCLUSION: Thermal stimulation can promote EMT in A549 and NCI-H446 cells and promote cell migration and invasion in vitro and in vivo by upregulation of Hsp70. This process is associated with the promotion of SUMO modification of HIF-1α.

Circular RNA hsa_circ_0002483 promotes growth and invasion of lung adenocarcinoma by sponging miR-125a-3p.

BACKGROUND: Increasing evidence indicates that the aberrant expression of circular RNAs (circRNAs) is involved in the pathogenesis and progression of lung adenocarcinoma (LUAC). However, the function and molecular mechanisms of hsa_circ_0002483 (circ_0002483) in LUAC remain unclear. METHODS: The association between circ_0002483 expression and clinicopathological characteristics and prognosis in patients with LUAC was analyzed by fluorescence in situ hybridization. The functional experiments such as CCK-8, colony formation and Transwell assays and a subcutaneous tumor model were conducted to determine the role of circ_0002483 in LUAC cells. The specific binding between circ_0002483 and miR-125a-3p was validated by RNA immunoprecipitation, luciferase gene report and qRT-PCR assays. The effects of circ_0002483 on miR-125a-3p-mediated C-C motif chemokine ligand 4 (CCL4)-CCR5 axis were assessed by Western blot analysis. RESULTS: We found that circ_0002483 was upregulated in LUAC tissue samples and associated with Tumor Node Metastasis (TNM) stage and poor survival in patients with LUAC. Knockdown of circ_0002483 inhibited proliferation, colony formation and invasion of A549 and PC9 cells in vitro, whereas overexpression of circ_0002483 harbored the opposite effects. Furthermore, circ_0002483 sponged miR-125a-3p and negatively regulated its expression. CCL4 was identified as a direct target of miR-125a-3p. The rescue experiments showed that miR-125a-3p mimics reversed the tumor-promoting effects of circ_0002483 by targeting CCL4-CCR5 axis in A549 and PC9 cells. In addition, the in vivo experiment further validated that knockdown of circ_0002483 repressed tumor growth. CONCLUSIONS: Our findings demonstrated that circ_0002483 could act as a sponge of miR-125a-3p to upregulate CCL4-CCR5 axis, contributing to the tumorigenesis of LUAC, and represent a potential therapeutic target for LUAC.

Changes in Expressions of HSP27, HSP70, and Soluble Glycoprotein in Heart Failure Rats Complicated with Pulmonary Edema and Correlations with Cardiopulmonary Functions.

The study is aimed at investigating the changes in expressions of heat shock protein 27 (HSP27), HSP70, and soluble glycoprotein (SGP) in heart failure (HF) rats complicated with pulmonary edema and exploring their potential correlations with cardiopulmonary functions. The rat model of HF was established, and the rats were divided into HF model group (model group, n = 15) and normal group (n = 15). After successful modeling, MRI and ECG were applied to detect the cardiac function indexes of the rats. The myocardial function indexes were determined, the injury of myocardial tissues was observed via hematoxylin and eosin (HE) staining, and the content of myeloperoxidase (MPO), matrix metalloproteinase-9 (MMP-9), and tumor necrosis factor-alpha (TNF-α) in the blood was measured. The partial pressure of oxygen (PaO2) and oxygenation index (OI) were observed, and the airway resistance and lung compliance were examined. Moreover, quantitative polymerase chain reaction (qPCR) and Western blotting assay were performed to detect the gene and protein expression levels of HSP27, HSP70, and SGP130. The levels of serum creatine kinase (CK), creatine (Cr), and blood urea nitrogen (BUN) were increased markedly in model group (p < 0.05). Model group had notably decreased fractional shortening (FS) and ejection fraction (EF) compared with normal group (p < 0.05), while the opposite results of left ventricular end-diastolic diameter (LVEDD) and left ventricular end-systolic diameter (LVESD) were detected. In model group, the content of serum MPO, MMP-9, and TNF-α was raised remarkably (p < 0.05), OI and PaO2 were reduced notably (p < 0.05), the airway resistance was increased (p < 0.05), and the lung compliance was decreased (p < 0.05). Obviously elevated gene and protein expression levels of HSP27, HSP70, and SGP130 were detected in model group (p < 0.05). The expressions of HSP27, HSP70, and SGP130 are increased in HF rats complicated with pulmonary edema, seriously affecting the cardiopulmonary functions of the rats.

Thermal treatment decreases resistance to osimertinib in non-small cell lung cancer through the EGFR/PI3K/AKT pathway.

Osimertinib (OSI) resistance commonly occurs during the treatment of non-small-cell lung cancer (NSCLC). This study aims to investigate whether the thermal effects of radiofrequency ablation (RFA) can increase the sensitivity of OSI-resistant NSCLC to OSI treatment and whether OSI effectively inhibits the recurrence of OSI-resistant NSCLC following RFA treatment and improve survival of NSCLC patients. In vitro, OSI-resistant NCI-H1975 (NCI-H1975/OSIR) cells and thermotolerant NCI-H1975/OSIR (NCI-H1975/OSIR-a-h) cells were established using human NSCLC cell line NCI-H1975. Cell viability, apoptosis, sensitivity to OSI, threonine-methionine amino acid substitution at position 790 (T790M) mutation levels, and protein expression of epidermal growth factor receptor (EGFR), phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), hypoxia-inducible factor-1 alpha (HIF-1a) were detected using different methods. In vivo, a nude mouse model of metastatic human lung cancer was developed and subjected to RFA treatment. The tumor growth, apoptosis, sensitivity to OSI, expression of EGFR/PI3K/AKT/HIF-1a, and CD34 levels were detected in the micrometastases of the transition zone (TZ) around the central ablation zone, and the reference zone (RZ) far from central ablation zone. NCI-H1975/OSIR and thermotolerant NCI-H1975/OSIR cell models were successfully established. Thermotolerant NCI-H1975/OSIR cells show higher sensitivity to OSI than NCI-H1975/OSIR cells and NCI-H1975 cells. OSI treatment can inhibit the EGFR/PI3K/AKT pathway and induce apoptosis in both NCI-H1975 cells and thermotolerant NCI-H1975/OSIR cells, but not in NCI-H1975/OSIR cells. In vivo, RFA treatment increases sensitivity to OSI in NCI-H1975/OSIR cell micrometastases in the TZ but not in the RZ. OSI intervention effectively inhibits the over-proliferation of micrometastases and activation of the EGFR/PI3K/AKT pathway, and induces apoptosis of micrometastases in the TZ, but shows little effects on the micrometastases in the RZ. The thermal effects can increase the sensitivity of OSI-resistant NSCLC cells to OSI through the EGFR/PI3K/AKT/HIF-1a signaling pathway, indicating that RFA combined with OSI might be a clinically effective and comprehensive therapy for the treatment of OSI-resistant NSCLC.

Prognostic Role of Soluble Programmed Death Ligand 1 in Non-Small Cell Lung Cancer: A Systematic Review and Meta-Analysis.

OBJECTIVE: The objective of this study was to explore whether soluble programmed death ligand 1 (sPD-L1) is a potential prognostic biomarker in patients with non-small cell lung cancer (NSCLC). METHODS: A comprehensive search of electronic databases was carried out. Original studies with inclusion of sPD-L1, progression-free survival, and overall survival in NSCLC were eligible. The primary endpoints were overall survival and progression-free survival. Hazard ratios (HRs) and 95% confidence intervals (CIs) were applied for data analysis. RESULTS: Eight studies involving 710 patients with NSCLC were included in the analysis. A pooled data analysis revealed that high levels of sPD-L1 were correlated with poorer overall survival (HR = 2.34; 95% CI = 1.82-3.00; P < 0.001) and progression-free survival (HR = 2.35; 95% CI = 1.62-3.40, P < 0.001). A subgroup analysis revealed that high levels of sPD-L1 were correlated with poor overall survival in patients treated with immunotherapy (HR = 2.40; 95% CI = 1.79-3.22; P < 0.001). CONCLUSION: This pooled analysis of published data suggests that sPD-L1 may serve as a readily available biomarker for survival in NSCLC patients treated with ICI based treatment. Prospective studies with well-designed standard assessment methods should be conducted to validate the prognostic role of sPD-L1 in NSCLC. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021283177.

Inhibitory effect of Ubenimex combined with fluorouracil on multiple drug resistance and P-glycoprotein expression level in non-small lung cancer.

Tumour drug resistance is one of the most urgent issues faced by anti-tumour therapies. P-glycoprotein (P-gp) has been reported to be correlated with drug resistance. In this study, we aimed to study the synergistic effect of fluorouracil (5FU) and Ubenimex (UBE) on drug resistance in lung cancer. In this study, the tumour inhibitory role of 5FU and UBE was assessed in nude mice bearing A549 or A549/ADR. Real-time polymerase chain reaction, Western blot and immunohistochemical were performed to analyse the mRNA and protein expression of P-gp. TUNEL assay was used to evaluate the apoptosis of A549/ADR cells under 5FU and UBE treatment. MTT assay was performed to calculate the IC50 value of 5FU and UBE in A549 or A549/ADR. Combined administration of 5FU and UBE significantly inhibited the tumour growth of multidrug-resistant cell lines A549/ADR in nude mice by down-regulating the mRNA and protein expression of P-gp. The apoptosis of A549/ADR was remarkably elevated in nude mice treated with 5FU and UBE. The IC50 value of 5FU and UBE was dramatically declined in A549/ADR cells compared with that of 5FU or UBE alone. Combined treatment of 5FU and UBE remarkably enhanced the apoptosis of A549/ADR cells by enhancing the intracellular accumulation of the drugs. The results of this study demonstrated that UBE combined with fluorouracil attenuated multiple drug resistance and inhibited the expression of P-gp in lung cancer.

A cell membrane vehicle co-delivering sorafenib and doxorubicin remodel the tumor microenvironment and enhance immunotherapy by inducing immunogenic cell death in lung cancer cells.

Cancer immunotherapy is a promising approach for cancer therapy but is usually hindered by the inhibition of the tumor microenvironment (TME). Herein, we developed a cell membrane vehicle (CV) to co-deliver doxorubicin (Dox) and sorafenib (Sfn) as a drug delivery system (CV/D-S) to regulate the TME and sensitize the immunogenic cell death (ICD)-induced immune response against tumors. The CV/D-S showed high stability, acid-responsive drug release, high biocompatibility with tumor-specific cellular uptake, and target-ability that preferably resulted in the in vitro and in vivo anticancer performance. Most importantly, the Dox in the DDS can induce significant ICD while Sfn was able to remodel the TME, downregulate Treg, activate effector T cells and relieve programmed cell death protein 1 (PD-1) expression. As a result, the synergistic effect of Dox and Sfn achieved strong immune response in CV/D-S treated mice, which is believed to open a new window for the design and development of future platforms for the more effective immunotherapy of cancer.

Independent prognostic value of HIF-1α expression in radiofrequency ablation of lung cancer.

Radiofrequency ablation (RFA) is widely used in the treatment of lung cancer. Hypoxia-inducible factor-1α (HIF-1α) is a crucial transcription factor regulating oxygen homeostasis that is involved in tumor cell metastasis. The present study investigated the impact of HIF-1α expression and other factors, such as postoperative blood CD4+/CD8+ ratio, on the prognosis of patients with lung cancer who had received RFA treatment. A total of 80 patients with lung cancer were recruited between January 2011 and October 2016 at The Shenzhen People's Hospital. Lung cancer was confirmed following pathological or histological examination. All patients underwent RFA treatment. Patients were followed up for 6-66 months. HIF-1α expression in lung cancer tissues was assessed by immunohistochemistry. Multivariate survival analysis was performed using Cox proportional hazards model. The results demonstrated that HIF-1α level was low in 36 patients and overexpressed in 44 patients with lung cancer. Kaplan-Meier (KM) curve analysis demonstrated that the overall survival time of patients with high HIF-1α expression was significantly shorter compared with patients with low HIF-1α expression (P<0.05). Furthermore, the results from the KM model and log-rank test revealed that age, Union for International Cancer Control stage, primary or metastatic cancer, chemotherapy, postoperative blood CD4+/CD8+ ratio, Eastern Cooperative Oncology Group performance status and HIF-1α expression had significant effects on overall survival of patients with lung cancer. The results from Cox analysis demonstrated that high HIF-1α expression, advanced age, clinical staging and chemotherapy were independent risk factors for the prognosis of lung cancer following RFA treatment, and that high HIF-1α expression was associated with the increased risk (5.91-fold) of mortality. In conclusion, the present study demonstrated that HIF-1α expression was increased in lung cancer tissues and was associated with the prognosis of patients with lung cancer who were treated with RFA. These findings suggest that HIF-1α expression may be considered as a marker for evaluating the prognosis of these patients.

miR-142-5p regulates CD4+ T cells in human non-small cell lung cancer through PD-L1 expression via the PTEN pathway.

The present study aimed to evaluate the function of microRNA (miR)-142-5p on cancer immunity to induce apoptosis in human non-small cell lung cancer (NSCLC) and its mechanism. miR-142-5p expression was upregulated, and CD4+ T cell levels were reduced in patients with NSCLC. Overexpression of miR-142-5p expression inhibited the cancer effects of CD4+ T cells on NSCLC cell lines, and downregulation of miR-142-5p increased the cancer effects of CD4+ T cells on NSCLC cell lines, compared with the control group. In addition, we found that overexpression of miR-142-5p suppressed PTEN protein expression and induced PI3K, p-Akt and PD-L1 protein expression in an in vitro model of NSCLC. Downregulation of miR-142-5p induced PTEN and PD-L1 protein expression and suppressed PI3K and p-Akt and protein expression in an in vitro model of NSCLC. The suppression of PD-L1 reduced the cancer effects of CD4+ T cells on NSCLC cell lines following miR-142-5p downregulation. The inhibition of PTEN also reduced the cancer effects of CD4+ T cells on NSCLC cell lines following miR-142-5p downregulation. Therefore, our study demonstrated that miR-142-5p regulated CD4+ T cells in human NSCLC through PD-L1 expression via the PTEN pathway.