Long-term results of surgical treatment of non-small cell lung cancer in patients over 75 years of age

The relation of body adiposity to the outcomes of thoracoscopic lobectomy for lung cancer - a single-center cohort study

Introduction

The outcomes of lung cancer surgery depend on the patients' nutritional status. Body fat percentage (BF%) is one of the indicators of body composition and nutritional status. Direct measurement of BF% is complicated, requires significant resources and is rarely performed. The CUN-BAE (Clínica Universidad de Navarra - Body Adiposity Estimator) index has been shown to accurately predict BF% is several clinical settings, but its relation to the outcomes of lung surgery has not been reported so far.

Aim

To determine the relation of the BF% to the outcomes of thoracoscopic lobectomy.

Material and methods

This retrospective study included 1,183 patients who underwent thoracoscopic lobectomy for non-small cell lung cancer between June 1999, and September 2019 at one department. BF% was calculated according to the Clínica Universidad de Navarra - Body Adiposity Estimator equation. The primary endpoints were postoperative complications and long-term survival.

Results

Univariate analysis showed that higher BF% was related to lower incidence of complications (p = 0.001), including prolonged air leak (p < 0.001), atelectasis (p < 0.05), psychosis (p < 0.001), reoperations (p < 0.05), and shorter chest drainage (p = 0.001) and hospitalization duration (p < 0.001). Multivariate analysis showed that higher BF% was correlated with lower risk of complications (p = 0.005; OR = 0.964; 95% CI: 0.940 to 0.989), including prolonged air leak (p < 0.001; OR = 0.923; 95% CI: 0.886 to 0.962), and shorter duration of chest drainage (p < 0.001; B = -0.046; 95% CI: -0.069 to -0.023) and hospitalization (p < 0.001; B = -0.112; 95% CI: -0.176 to -0.048). Cox proportional hazards regression analysis showed that BF% was not related to long-term survival.

Conclusions

Body fat percentage is a valuable tool that can help predict the short-term outcomes of minimally lobectomy for lung cancer.

The technique of stump closure has no impact on post-pneumonectomy bronchopleural fistula in the non-small cell lung cancer-a cross-sectional study

Background

Pneumonectomy is a high-risk radical resection procedure, with bronchopleural fistula (BPF) being its most challenging and severe complication. This study aimed to assess the surgical risk factors and the impact of the bronchial stump closure technique on the incidence of the BPF.

Methods

This is a single-center, cross-sectional study of the medical records of 455 post-pneumonectomy patients operated due to non-small cell lung cancer (NSCLC) in 2006-2017. We analyzed the following variables and their influence on the occurrence of the BPF: operation side, surgical techniques (i.e., manual suture or the stapler), stump buttressing, the extension of pneumonectomy, comorbidities, and postoperative complications.

Results

BPF occurred in 7.47% of post-pneumonectomy patients. BPF was more prevalent in right-sided pneumonectomy versus left-sided (10.98% vs. 5.32%; P=0.026). The use of a stapler or manual suture was not associated with the incidence of the BPF (7.96% vs.7.09%, P=0.72). There were no significant differences in the occurrence of BPF among bronchial stump buttressing with the parietal pleura (P=0.80), intercostal muscle flap (IMF) (P=0.46), and pericardial fat pad (P=0.88). When comparing data from 2006-2012 with those from 2013-2017, we found a steady decrease in the number of performed stump reinforcements, but this was not associated with a higher risk of BPF.

Conclusions

The method used for stump closure, additional tissue buttressing of the bronchial stump and year of the surgery had no significant impact on the occurrence of BPF. Only right-sided pneumonectomy was associated with higher BPF occurrence.

F-circEA1 regulates cell proliferation and apoptosis through ALK downstream signaling pathway in non-small cell lung cancer

Studies have confirmed that circular RNA (circRNA) has a stable closed structure, which plays an important role in the progression of tumors. Cancers with positive fusion genes can produce associated fusion circRNA (F-cirRNA). However, there are no reports concerning a role for F-circRNA of the echinoderm microtubule associated-protein like 4-anaplastic lymphoma kinase variant 1 (EML4-ALK1) in non-small cell lung cancer (NSCLC). Our study confirmed the existence of fusion circEA1 (F-circEA1) in NCI-H3122 cells (carrying the EML4-ALK1 gene), F-circEA1 was expressed both in the cytoplasm and nucleus as determined by fluorescence in situ hybridization (FISH) and Sanger sequencing. CCK8 and transwell assays showed that F-circEA1 was beneficial to cell proliferation, metastasis, and invasion. Overexpression of F-circEA1 can also promote cell proliferation, migration and invasion in A549 and SPCA1 cells (non-small cell lung cancer cell line not carrying the EML4-ALK1 gene). Interference with F-circEA1, induced cell cycle arrest and promoted apoptosis as determined by flow cytometry, and increased drug sensitivity to crizotinib in H3122 cells. F-circEA1 directly affected the expression of parental gene EML4-ALK1. Further research found that F-circEA1 can affect the downstream signaling pathway of ALK. In vivo, the growth rate of xenogeneic tumors was reduced and the protein expression level of EML4-ALK1 was significantly decreased in transplanted tumors measured by immunohistochemistry (IHC) after interference with F-circEA1. In conclusion, F-circEA1 can be considered as a proto-oncogene that regulates cell proliferation and apoptosis by affecting the expression of the parental gene EML4-ALK1 and its ALK downstream signaling pathway in non-small cell lung cancer.

Development of a Survival Prognostic Model for Non-small Cell Lung Cancer

Lung cancer is a leading cause of cancer-related death, and >80% of lung cancer diagnoses are non-small-cell lung cancer (NSCLC). However, when using current staging and prognostic indices, the prognosis can vary significantly. In the present study, we calculated a prognostic index for predicting overall survival (OS) in NSCLC patients. The data of 545 NSCLC patients were retrospectively reviewed. Univariate and multivariate Cox proportional hazards regression analyses were performed to evaluate the prognostic value of clinicopathological factors. Age (hazard ratio [HR] = 1.25, 95% confidence interval [CI] = 1.02–1.54), TNM stage (III, HR = 1.64, 95% CI = 1.08–2.48; IV, HR = 2.33, 95% CI = 1.48–3.69), lung lobectomy (HR = 1.96, 95% CI = 1.45–2.66), chemotherapy (HR = 1.42, 95% CI = 1.15–1.74), and pretreatment hemoglobin level (HR = 1.61, 95% CI = 1.28–2.02) were independent prognosticators. A prognostic index for NSCLC (PInscl, 0–6 points) was calculated based on age (≥65 years, 1 point), tumor-node-metastasis (TNM) stage (III, 1 point; IV, 2 points), lung lobectomy (no, 1 point), chemotherapy (no, 1 point), and pretreatment hemoglobin level (low, 1 point). In comparison with the “PInscl = 0” subgroup (survival time = 2.71 ± 1.86 years), the “PInscl = 2” subgroup (survival time = 1.86 ± 1.24 years), “PInscl = 3” subgroup (survival time = 1.45 ± 1.07 years), “PInscl = 4” subgroup (survival time = 1.17 ± 1.06 years), “PInscl = 5” subgroup (survival time = 0.81 ± 0.78 years), and “PInscl = 6” subgroup (survival time = 0.65 ± 0.56 years) exhibited significantly shorter survival times. Kaplan-Meier survival analysis showed that patients with higher PInscl scores had poorer OS than those with lower scores (log-rank test: χ² = 155.82, P < 0.0001). The area under the curve of PInscl for predicting the 1-year OS was 0.73 (95 % CI = 0.69–0.77, P < 0.001), and the PInscl had a better diagnostic performance than the Karnofsky performance status or TNM stage (P < 0.01). In conclusion, the PInscl, which is calculated from age, TNM stage, lung lobectomy, chemotherapy, and pretreatment hemoglobin level, significantly predicted OS in NSCLC patients.

IL‑21/IL‑21R inhibit tumor growth and invasion in non‑small cell lung cancer cells via suppressing Wnt/β‑catenin signaling and PD‑L1 expression

Lung cancer is considered to be one of the world's deadliest diseases, with non-small cell lung cancer (NSCLC) accounting for 85% of all lung cancer cases. The present study aimed to investigate the role and underlying mechanisms of interleukin-21 (IL-21), and its receptor IL-21R, in NSCLC. Lung tissues and blood samples of NSCLC were used to measure IL-21, IL-21R and programmed death 1 ligand 1 (PD-L1) expression using ELISA, western blot and immunohistochemistry analyses. Following treatment with different doses of IL-21, the proliferation, invasion and migration of human NSCLC cell line A549 was evaluated using a cell counting kit-8, colony formation, Transwell and scratch wound healing assays, respectively. Additionally, IL-21R and PD-L1 expression in A549 cells was detected using western blot analysis and immunofluorescence. IL-21R silencing was subsequently used to investigate its effects in cell proliferation, invasion and migration. PD-L1, IL-1β and tumor necrosis factor α (TNF-α) expression were measured. Finally, Wnt/β-catenin signaling expression was evaluated using western blot analysis following treatment with IL-21. Cells were then treated with lithium chloride (LiCl), which is an agonist of Wnt/β-catenin signaling, and the levels of PD-L1, IL-1β and TNF-α were detected. The results revealed that IL-21 and IL-21R expression in the lung tissues and blood samples of patients with NSCLC were decreased, while PD-L1 expression was increased, compared with normal tissues or healthy controls. Treatment of A549 cells with IL-21 upregulated IL-21R expression, downregulated PD-L1 and inhibited cell growth and metastasis in a dose-dependent manner. Following IL-21R silencing, the effects of IL-21 treatment were reversed, suggesting that IL-21 acted on A549 cells through binding to IL-21R. In addition, the results demonstrated that IL-21 treatment reduced the expression levels of proteins associated with the Wnt/β-catenin signaling, whereas activation of Wnt/β-catenin signaling with the LiCl agonist upregulated PD-L1, IL-1β and TNF-α expression. In conclusion, the IL-21/IL-21R axis reduced the growth and invasion of NSCLC cells via inhibiting Wnt/β-catenin signaling and PD-L1 expression. The present results may provide a novel molecular target for NSCLC diagnosis and therapy.

miRNA-101-5p inhibits the growth and aggressiveness of NSCLC cells through targeting CXCL6

Background

The purpose of this study is to explore the potential biological roles of miR-101-5p in the progression of non-small-cell lung carcinoma (NSCLC).

Methods

The levels of miR-101-5p and chemokine (C-X-C motif) ligand 6 (CXCL6) in NSCLC tissues and cells were detected using the quantitative real-time PCR (qRT-PCR) assay. Proliferation, colony formation, migration and invasion assays were conducted using miR-101-5p-transfected NSCLC cells in vitro. The expression of CXCL6 was measured using immunofluorescence assay. Xenograft model and lung metastasis model were constructed to further reveal the precise roles of miR-101-5p in the lung metastasis and growth of NSCLC cells in vivo.

Results

miR-101-5p was underregulated in NSCLC tissues when compared with that in the normal controls. The levels of miR-101-5p were lower in NSCLC cells (H1975, A549, HCC827 and H1650) than in non-tumorigenic human bronchial epithelial cells (BEAS-2B). Overregulation of miR-101-5p restrained the aggressiveness phenotypes of NSCLC cells in vitro. Furthermore, overregulation of miR-101-5p reduced the tumor growth and pulmonary metastasis of NSCLC cells in vivo. CXCL6 was the target gene of miR-101-5p in NSCLC. The mRNA levels of CXCL6 were negatively associated with the levels of miR-101-5p in NSCLC tissues. Finally, the rescue experiments suggested that the inhibitory role of miR-101-5p was mediated by regulating the expression of CXCL6 in NSCLC.

Conclusion

These findings indicated that overregulation of miR-101-5p restrained the progression of NSCLC cells by targeting CXCL6 and might function as a potential therapeutic target for NSCLC.