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.

Potential biomarkers and resistance mechanisms of atezolizumab in a patient with lung squamous cell carcinoma.

Background: At present, only a small fraction of patients with cancer benefit from treatment with immune checkpoint inhibitors, the reasons for which are not fully understood. Monitoring molecular and immunologic changes during treatment with immune checkpoint inhibitors would help to identify potential biomarkers and mechanisms associated with resistance and guide subsequent treatment. Methods: The authors report on a patient previously treated for lung squamous cell carcinoma who received atezolizumab-based therapy for 24 months. Results & Conclusion: Analysis of samples before and after atezolizumab treatment suggested that genetic mutations in EGFR exon 20 insertion, phosphatase and PTEN and NOTCH1 as well as changes in tumor immune microenvironment may be associated with acquired resistance to immune checkpoint inhibitor therapy.

Lay abstract The authors aimed to figure out potential biomarkers and mechanisms associated with immune checkpoint inhibitor resistance by monitoring changes during treatment in a lung squamous cell cancer patient. Interestingly, EGFR exon 20 insertion, decreased PTEN copy number and NOTCH1 mutation as well as changes in CD8⁺ T cells and macrophages were observed after disease progression. Thus, the authors suggest that these changes may be associated with atezolizumab resistance.

miR­10a increases the cisplatin resistance of lung adenocarcinoma circulating tumor cells via targeting PIK3CA in the PI3K/Akt pathway.

Circulating tumor cells (CTCs) that are shed from the primary tumor invade the blood stream or surrounding parenchyma to form new tumors. The present study aimed to explore the underlying mechanism of cisplatin resistance in lung adenocarcinoma CTCs and provide clinical treatment guidance for lung cancer treatment. CTCs from the blood samples of 6 lung adenocarcinoma patients were treated with different concentrations of cisplatin along with A549 and H1299 cells. The sensitivity of CTCs to cisplatin was explored by detecting the inhibitory rate via CCK­8 assay. The related molecular mechanism was investigated by western blot analysis. miR­10a expression was detected using quantitative real­time PCR (RT­qPCR). The relationship between miR­10a and phosphatidylinositol­4,5­bisphosphate 3­kinase catalytic subunit α (PIK3CA) was verified and further confirmed by luciferase reporter assay, western blotting and RT­qPCR assay. The results revealed that CTCs exhibited lower cisplatin sensitivity than A549 and H1299 cells. Moreover, CTCs treated with cisplatin demonstrated higher miR­10a expression and lower PIK3CA expression than that in A549 and H1299 cells (P<0.01). Expression of phosphoinositide 3­kinase (PI3K) and protein kinase B (Akt) phosphorylation were also decreased in A549 and H1299 cells compared with CTCs after cisplatin treatment. PIK3CA is a target of miR­10a, and both miR­10a overexpression and PIK3CA knockdown obviously decreased the sensitivity of A549 and H1299 cells to cisplatin as well as the expression of PI3K and phosphorylation of Akt. PIK3CA overexpression attenuated the cisplatin resistance of A549 and H1299 cells induced by miR­10a. In conclusion, miR­10a suppressed the PI3K/Akt pathway to strengthen the resistance of CTCs to cisplatin via targeting PIK3CA, providing a new therapeutic target for lung cancer treatment.

MiR-186 inhibits proliferation, migration, and invasion of non-small cell lung cancer cells by downregulating Yin Yang 1.

BACKGROUND: Non-small cell lung cancer (NSCLC) is the main type of lung cancer. While miR-186 is significantly reduced in lung cancer tissues and cells, its role in NSCLC has not been completely elucidated. MATERIAL AND METHODS: We used qRT-PCR and western blot methods to investigate the levels of miR-186 and YY1 in 21 pairs of NSCLC tissues. Dual luciferase reporter gene assays were performed to detect whether miR-186 directly targets YY1. Next, the roles of miR-186 and its target gene (YY1) in determining the proliferation, apoptosis and migration capabilities of selected cell lines (A549 and HCC827) were investigated by using miR-186 mimics or YY1 siRNA. RESULTS: Our results showed that miR-186 was downregulated and YYI was upregulated in NSCLC tissue, and miR-186 expression was negatively associated with YY1. Similarly, miR-186 was also downregulated and YY1 expression also was upregulated in both A549 and HCC827 cells; furthermore, miR-186 was found to directly target YY1. Cell proliferation, invasion, and migration, as well as apoptosis induction were more strongly inhibited by YY1 siRNA than by miR-186. CONCLUSION: Our results suggest that miR-186 and its target gene (YY1) could possibly serve as new prognostic biomarkers and therapeutic targets for treating NSCLC in humans.

Transcription Factor YY1 Modulates Lung Cancer Progression by Activating lncRNA-PVT1.

Lung cancer is the leading cause of cancer-related death worldwide. Despite the advancement in surgery and chemotherapy, the prognosis of patients with advanced lung cancer is still poor. Yin Yang-1 (YY1) is a multifunctional transcription factor that exhibits positive and negative control on a large number of cellular and viral genes. In this study, we showed that the expression of YY1 is upregulated in lung cancer tissues as compared to adjacent normal tissues. Patients with higher expression of YY1 had larger tumor size, poor differentiation, higher TNM stage, and lymph node metastasis. Ectopic expression of YY1 in lung cancer cells promoted cell proliferation and invasion. Inversely, siRNA-mediated silencing of YY1 inhibited cell proliferation and induced apoptosis. These results suggested that YY1 may function as an oncogene in lung cancer. Moreover, through luciferase reporter assay, electrophoretic mobility shift assay, and chromatin immunoprecipitation assay, we showed that YY1 could directly bind to the promoter region of (long noncoding RNA-plasmacytoma variant translocation 1 [lncRNA-PVT1]) and activated its transcription through the consensus YY1 motif. Knockdown of the expression of YY1 reduced cell proliferation in vivo, consistent with the results obtained from silencing the expression of YY1 in lung cancer cells. Collectively, our study showed a critical role of YY1 in the regulation of tumorigenesis, partly through its downstream target PVT1.

Inhibition of Skp2 sensitizes lung cancer cells to paclitaxel.

S-phase kinase-associated protein 2 (Skp2) is an E3 ubiquitin ligase and plays an important role in the control of cell cycle progression. Skp2 is upregulated in several cancers, including lung cancers, but the role of Skp2 in the tumorigenesis and anticancer drug resistance in human lung cancer remains to be determined. We report here that Skp2 positively regulated mitotic arrest deficient 2 (MAD2) expression and that inhibition of Skp2 sensitizes human lung cancer cells to paclitaxel. Knockdown of Skp2 by small interfering RNA (siRNA) decreased Mad2 messenger RNA (mRNA) and protein levels in A549 and NCI-H1975 cells, accompanied with upregulation of p27 but decrease of the phosphorylation of retinoblastoma (Rb). In contrast, ectopic overexpression of Skp2 increased Mad2 mRNA and protein levels and phosphorylation of Rb, while it decreased p27. Pharmacological inhibition of CDK1/2 by flavopiridol or E2F1 with HLM006474 led to downregulation of Mad2 expression and prevented the increase of Mad2 expression by Skp2. Most importantly, pharmacological inhibition of Skp2 sensitized A549 and NCI-H1299 cells to paclitaxel. Our results demonstrated that SKP2 positively regulates the gene expression of MAD2 through p27-CDKs-E2F1 signaling pathway and that inhibition of Skp2 sensitizes A549 and NCI-H1299 cells to paclitaxel, suggesting that small molecule inhibitors of Skp2 are potential agents for the treatment of lung cancer with upregulation of Skp2.

Upregulated lncRNA H19 promotes non-small cell lung cancer cell proliferation through miR-138/PDK1 axis.

Long non-coding RNA (lncRNA) H19 was reported to be aberrantly expressed and implicated in non-small cell lung cancer (NSCLC). However, the regulation of NSCLC progression by H19 was not well understood. In this study, we found that the expression level of H19 was obviously increased, but miR-138 was decreased in NSCLC tissues and NSCLC cells including A549, H1299 and H460 cells. Upregulation of H19 promotes cell proliferation ability in A549 and H460 cells, while downregulation of H19 did the opposite. H19 represses miR138 expression and H19 expression level was negatively correlated with miR-138 expression level in NSCLC tissues. Moreover, overexpression of mutant H19 (Mut-H19) has no effect on miR-138 expression in A549 and H460 cells. Dual luciferase reporter assay showed that PDK1 was a target gene of miR-138. Overexpression of H19 attenuated the inhibitory effect of miR-138 on PDK1 protein expression. The inhibition of NSCLC cell proliferation induced by H19 knockdown required the activity of miR-138, and could be reversed by overexpression of PDK1. Overall, we concluded that H19 upregulates the expression of PDK1 through downregulation of miR-138 to promote NSCLC cell proliferation. H19 could potentially be employed as a therapeutic target for the treatment of NSCLC.

lncRNA-SNHG7 promotes the proliferation, migration and invasion and inhibits apoptosis of lung cancer cells by enhancing the FAIM2 expression.

There is growing evidence that long non-coding RNAs (lncRNAs) are related to cancer development. In the present study, we found that the expression levels of lncRNA-SNHG7 mRNA and protein obviously increased in lung cancer tissues compared to adjacent non-cancerous tissues. Simultaneously, the expression levels of Fas apoptotic inhibitory molecule 2 (FAIM2) also increased in lung cancer tissues. In addition, lncRNA-SNHG7 was of positive relevance with FAIM2 in human lung cancer tissues. Silence of lncRNA­SNHG7 by siRNA repressed the level of FAIM2 protein and suppressed cell proliferation, migration and invasion and accelerated apoptosis of A594 cells in vitro. Furthermore, silence of FAIM2 by siRNA generated a phenotype similar to silence of lncRNA-SNHG7 by siRNA. Therefore, our research showed that lncRNA-SNHG7 promotes the proliferation, migration and invasion, and inhibits apoptosis of lung cancer cells by enhancing the FAIM2 expression, suggesting that lncRNA-SNHG7 as a key regulator of gene expression, may be a promising therapeutic strategy for the treatment of lung cancer. It may improve the understanding of their biogenesis and function of lung cancer and further provide the theoretical fundamental basis for cancer pathogenesis and treatment.

MicroRNA-186 suppresses cell proliferation and metastasis through targeting MAP3K2 in non-small cell lung cancer.

MicroRNAs are a class of small endogenous non-coding RNAs that play crucial roles in the initiation and progression of human cancers. miR-186 was found decreased in various human malignancies and function as a tumor suppressor. However, the regulating mechanism of miR-186 in growth and metastasis of human non-small cell lung cancer (NSCLC) is still poorly understood. We investigated the role of miR-186 in the growth and metastasis of human NSCLC. In the present study, we found that miR-186 was significantly decreased in lung cancer tissues and cells. Furthermore, overexpression of miR-186 suppressed lung cancer cell proliferation, migration and invasion, and induced cell apoptosis. Moreover, we found that confirmed mitogen-activated protein kinase kinase kinase 2 (MAP3K2) protein was increased in lung cancer tissues and confirmed that MAP3K2 is a target gene of miR-186. In addition, knockdown of MAP3K2 by RNA interference inhibited lung cancer cell proliferation, migration and invasion, and promoted cell apoptosis in vitro. Furthermore, we observed tthat the overexpression of MAP3K2 partially reversed the inhibitory effect of miR-186 on the proliferation and metastasis of A549 and HCC827 cell lines. Taken together, our data indicated that miR-186 regulates lung cancer growth and metastasis through suppressing MAP3K2 expression, at least partly. Therefore, miR-186-MAP3K2 may represent a new and useful potential clinical treatment and diagnosis target for NSCLC.

Uniportal video-assisted thoracoscopic anatomic segmentectomy for small-sized lung cancer.

Increasing evidences prove video-assisted thoracic surgery (VATS) segmentectomy is accepted as a valid alternative to lobectomy esp. a greater number of small lung nodules have been detected. Uniportal VATS segmentectomy for small-sized lung cancer is more challenging not only for technical issues in simple or complex uniportal segmentectomy, but also considering oncological efficacy in terms of localization, safe margin, the extent of lymph node dissection and pathological analysis. In this work, we evaluated our evolving uniportal experience, the surgical technique and decision-making of uniportal VATS segmentectomy for small-sized lung cancer.

Tuberculosis bronchopleural fistula treated with atrial septal defect occluder.

Bronchopleural fistula (BPF) is an uncommon and potentially fatal complication of lobectomy or pneumonectomy, particularly in tuberculosis patients. It is associated with high mortality and its treatment remains a challenge. The development of plugging technology has led to the emergence of less invasive endobronchial methods for treating BPF. We describe the successful treatment of a multidrug-resistant tuberculosis patient with BPF using an occlusion device originally designed for transcatheter closure of an atrial septal defect. Follow-up over 10 months revealed maintenance of the repair without any recurrence. This novel technique can be effective for treating a tuberculosis patient with postoperative BPF.

[Clinical significance of enrichment and detection of circulating tumor cells in NSCLC patients with immunomagnetic beads].

OBJECTIVE: To investigate the feasibility and clinical significance of detection of circulating tumor cells (CTCs) in peripheral blood of NSCLC patients by lung cancer cell immunomagnetic enrichment and detection kit. METHODS: Four groups of patients (Group A: 18 cases with stage I lung cancer; Group B: 33 cases with stage II - IV lung cancer; Group C: 20 cases with benign pulmonary diseases; Group D: 20 healthy volunteers) were enrolled for detection of CTCs using the lung cancer cell enrichment and detection kit developed by ourselves, and compared with the results obtained using simple ICC method and the detection of CK19 mRNA and LUNX mRNA using nested PCR as control. RESULTS: By using lung cancer cell enrichment and detection kit, it was revealed that the detection rates of CK positive cells were 33.3%, 60.6%, 0% and 0% in Group A, B, C and D, respectively. By using nested RT-PCR, the rates of positive expression of CK19 mRNA were 38.9%, 63.6%, 20.0% and 0% in Group A, B, C and D, respectively, and those of LUNX mRNA were 44.4%, 69.7%, 10.0% and 0%, respectively, while the detection rate of CTCs was negative in all groups using simple ICC. There was a significant difference between the results obtained by lung cancer cell enrichment and detection kit and simple ICC method (P < 0.05), while no significant difference was found between the results obtained by lung cancer cell enrichment and detection kit and nested RT-PCR (P > 0.05). There was a significant difference in the detection rates of CK positive cells between group A and groups B, C, D (P < 0.05). The micrometastasis in peripheral blood was closely related with pathological types, cell differentiation and TNM staging (P < 0.05). CONCLUSION: The lung cancer cell enrichment and detection kit developed by ourselves is a sensitive and reliable method to detect CTCs in patients with NSCLC. It may be helpful in diagnosis of NSCLC micrometastasis and circulating tumor cells in peripheral blood, re-determination of clinical stage and provide important information for cancer-therapy personalization.