Prognostic impact of microscopic vessel invasion and visceral pleural invasion and their correlations with epithelial-mesenchymal transition, cancer stemness, and treatment failure in lung adenocarcinoma

Pathological Pleural Invasion is a Risk Factor for Late Recurrence in Long-Term Survivors of Non-small Cell Lung Cancer after Complete Resection

BACKGROUND

Information regarding late recurrence after pulmonary resection for non-small cell lung cancer (NSCLC) is limited. This study aimed to analyze the risk factors for late recurrence after surgery for NSCLC in the current era.

PATIENTS AND METHODS

We conducted a retrospective study of patients who underwent complete resection for pathological I-III NSCLC between 2006 and 2015. Late recurrence was defined as a recurrence that met the following conditions: (1) the patient underwent chest computed tomography (CT) at or after 54 months after surgery and recurrence was not detected at that time, and (2) recurrence that occurred more than 5 years after surgery. The factors influencing late recurrence, relapse-free survival (RFS), and overall survival (OS) after surgery were analyzed.

RESULTS

A total of 1275 with 5-year relapse-free survival after surgery were enrolled in this study. The mean age of the patients was 66.4 years and 54% of the patients were men. The median interval between surgery and the latest follow-up examination was 98 months. In total, 35 patients (2.7%) experienced late recurrence and 138 patients have died thus far. The cumulative recurrence, RFS, and OS rates at 10 years were 3.9%, 84.9%, and 86.3%, respectively. A multivariate analysis revealed that pleural invasion was an independent risk factor for late recurrence. Pleural invasion was a poor prognostic factor for both RFS and OS.

CONCLUSIONS

Pleural invasion was a predictor of late recurrence. Age > 67 years, preoperative serum carcinoembryonic antigen (CEA) > 5 ng/ml, non-adenocarcinoma, and pleural invasion were poor prognostic factors for RFS.

M2-like tumor-associated macrophages promote epithelial-mesenchymal transition through the transforming growth factor β/Smad/zinc finger e-box binding homeobox pathway with increased metastatic potential and tumor cell proliferation in lung squamous cell carcinoma

Epithelial-mesenchymal transition (EMT) promotes primary tumor progression toward a metastatic state. The role of tumor-associated macrophages (TAMs) in inducing EMT in lung squamous cell carcinoma (LUSC) remains unclear. We aimed to clarify the significance of TAMs in relation to EMT in LUSC. We collected 221 LUSC specimens from patients who had undergone surgery. Immunohistochemistry was performed to evaluate M1-like and M2-like TAM distribution and EMT by E-cadherin and vimentin staining. Human LUSC cell lines (H226 and EBC-1) and a human monocyte cell line (THP-1) were used for in vitro experiments. M2-like polarization of TAMs and EMT marker expression in LUSC cells were evaluated by western blotting. The biological behavior of LUSC cells was evaluated by migration, invasion, and cell proliferation assays. Immunohistochemical analysis showed that 166 (75.1%) tumors were E-cadherin-positive and 44 (19.9%) were vimentin-positive. M2-like TAM density in the tumor stroma was significantly associated with vimentin positivity and worse overall survival. Western blotting demonstrated higher levels of CD163, CD206, vascular endothelial growth factor, and transforming growth factor beta 1 (TGF-β1) in TAMs versus unstimulated macrophages. Furthermore, increased TGF-β1 secretion from TAMs was confirmed by ELISA. TAM-co-cultured H226 and EBC-1 cells exhibited EMT (decreased E-cadherin, increased vimentin). Regarding EMT-activating transcriptional factors, phosphorylated Smad3 and ZEB-family proteins were higher in TAM-co-cultured LUSC cells than in parental cells. TAM-co-cultured H226 and EBC-1 cells demonstrated enhanced migration and invasion capabilities and improved proliferation. Overall, the present study suggests that TAMs can induce EMT with increased metastatic potential and tumor cell proliferation in LUSC.

Development and validation of 18F-FDG PET/CT radiomics-based nomogram to predict visceral pleural invasion in solid lung adenocarcinoma

OBJECTIVES

This study aimed to establish a radiomics model based on 18F-FDG PET/CT images to predict visceral pleural invasion (VPI) of solid lung adenocarcinoma preoperatively.

METHODS

We retrospectively enrolled 165 solid lung adenocarcinoma patients confirmed by histopathology with 18F-FDG PET/CT images. Patients were divided into training and validation at a ratio of 0.7. To find significant VPI predictors, we collected clinicopathological information and metabolic parameters measured from PET/CT images. Three-dimensional (3D) radiomics features were extracted from each PET and CT volume of interest (VOI). Receiver operating characteristic (ROC) curve was performed to determine the performance of the model. Accuracy, sensitivity, specificity and area under curve (AUC) were calculated. Finally, their performance was evaluated by concordance index (C-index) and decision curve analysis (DCA) in training and validation cohorts.

RESULTS

165 patients were divided into training cohort (n = 116) and validation cohort (n = 49). Multivariate analysis showed that histology grade, maximum standardized uptake value (SUVmax), distance from the lesion to the pleura (DLP) and the radiomics features had statistically significant differences between patients with and without VPI (P < 0.05). A nomogram was developed based on the logistic regression method. The accuracy of ROC curve analysis of this model was 75.86% in the training cohort (AUC: 0.867; C-index: 0.867; sensitivity: 0.694; specificity: 0.889) and the accuracy rate in validation cohort was 71.55% (AUC: 0.889; C-index: 0.819; sensitivity: 0.654; specificity: 0.739).

CONCLUSIONS

A PET/CT-based radiomics model was developed with SUVmax, histology grade, DLP, and radiomics features. It can be easily used for individualized VPI prediction.

Multi-dimensional radiomics analysis to predict visceral pleural invasion in lung adenocarcinoma of ≤3 cm maximum diameter

AIM

To explore the value of radiomics analysis in preoperatively predicting visceral pleural invasion (VPI) of lung adenocarcinoma (LAC) with ≤3 cm maximum diameter and to compare the performance of two-dimensional (2D) and three-dimensional (3D) computed tomography (CT) radiomics models.

MATERIALS AND METHODS

A total of 391 LAC patients were enrolled retrospectively, of whom 142 were VPI (+) and 249 were VPI (-). Radiomics features were extracted from 2D and 3D regions of interest (ROIs) of tumours in CT images. 2D and 3D radiomics models were developed combining the optimal radiomics features by using the logistic regression machine-learning method and radiomics scores (rad-scores) were calculated. Nomograms were constructed by integrating independent risk factors and rad-scores. The performance of each model was evaluated by using the receiver operator characteristic (ROC) curve, decision curve analysis (DCA), clinical impact curve (CIC), and calculating the area under the curve (AUC).

RESULTS

There was no difference in the VPI prediction between 2D and 3D radiomics models (training group: 2D AUC=0.835, 3D AUC=0.836, p=0.896; validation group: 2D AUC=0.803, 3D AUC=0.794, p=0.567). The 2D and 3D nomograms performed similarly regarding discrimination (training group: 2D AUC=0.867, 3D AUC=0.862, p=0.409, validation group: 2D AUC=0.835, 3D AUC=0.827, p=0.558), and outperformed their corresponding radiomics models and the clinical model. DCA and CIC revealed that the 2D nomogram had slightly better clinical utility.

CONCLUSION

The 2D radiomics model has a similar discrimination capability compared with the 3D radiomics model. The 2D nomogram performs slightly better for individual VPI prediction in LAC.

The location of visceral pleural invasion in stage IB patients with non-small cell lung cancer: Comparison and prognosis

OBJECTIVES

Recently, early-stage lung cancer has been drawing more attention, especially in screening and treatment. Visceral pleural invasion in stage IB cancer is considered as risk factor for poor prognosis. Herein, we aimed to study the distinction between the different locations of visceral pleural invasion.

METHODS

In this retrospective cohort study, we summarized 58,242 patient cases that underwent surgery from 2015 to 2018 at Shanghai Chest Hospital. Of those patients, 389 met the inclusion criteria. Patients with PL3 pleural invasion were excluded. The patients were dichotomized into the interlobar pleural and peripheral pleural groups. The outcomes measured were overall survival (OS) and recurrence-free survival (RFS) rates.

RESULTS

According to the initial analysis, the baseline characteristics of the two groups were largely balanced. In multivariate Cox analyses, we found that the location of visceral pleural invasion was not a risk factor for prognosis in the overall population (RFS: P = 0.726, OS: P = 0.599). However, we discovered that relative to patients with peripheral pleura invasion, those with interlobar pleura invasion, PL1 invasion, lesions with greater than 3 cm solid components, and those who underwent segmentectomy had a compromised prognosis. Additionally, tumors larger than 3 cm in size with interlobar pleura invasion showed poor prognosis in patients who underwent postoperative chemotherapy.

CONCLUSIONS

In most cases, the location of tumor invasion did not worsen the postoperative prognosis of stage IB non-small cell lung cancer patients with visceral pleural invasion. However, interlobar pleural invasion still had some potential risks compared to that of peripheral pleural invasion.

A novel cell-based assay for the high-throughput screening of epithelial-mesenchymal transition inhibitors: Identification of approved and investigational drugs that inhibit epithelial-mesenchymal transition

OBJECTIVES

Lung cancer with distant metastases is associated with a very poor prognosis, and epithelial-mesenchymal transition (EMT) contributes to cancer metastasis. Therefore, elucidation and inhibition of EMT signaling in lung cancer may be a new therapeutic strategy for improving the prognosis of patients. We constructed a high-throughput screening system for EMT inhibitors. Using this system, we aimed to identify compounds that indeed inhibit EMT.

MATERIALS AND METHODS

We generated a luciferase reporter cell line using A549 human lung cancer cells and E-cadherin or vimentin as EMT markers. EMT was induced by transforming growth factor β1 (TGF-β1), and candidate EMT inhibitors were screened from a library of 2,350 compounds. The selected compounds were further tested using secondary assays to verify the inhibition of EMT and invasive capacity of cells.

RESULTS

Values obtained by the assay were adjusted for the number of viable cells and scored by determining the difference between mean values of the positive and negative control groups. Four compounds were identified as novel candidate drugs. Among those, one (avagacestat) and two compounds (GDC-0879 and levothyroxine) improved the expression of E-cadherin and vimentin, respectively, in epithelial cells. GDC-0879 and levothyroxine also significantly inhibited the invasive capacity of cells.

CONCLUSION

We systematically screened approved, investigational, and druggable compounds with inhibitory effects using a reporter assay, and identified candidate drugs for EMT inhibition.

Validation of the novel International Association for the Study of Lung Cancer grading system and prognostic value of filigree micropapillary and discohesive growth pattern in invasive pulmonary adenocarcinoma

INTRODUCTION

The Pathology Committee of the International Association for the Study of Lung Cancer (IASLC) proposed a new histological grading system based on the combination of predominant and high-grade patterns in 2020.

MATERIALS AND METHODS

Pathological sections from 631 patients with stage I-III invasive lung adenocarcinoma were reviewed. We then determined the histological grade according to the new grading system and confirmed the pathological features that included the filigree micropapillary and discohesive growth pattern. Applying of the novel IASLC grading system in prognosis stratification was verified and the clinical significance of the pathological characteristics was explored.

RESULTS

Cox multivariable analysis revealed that in the stage I-III invasive lung adenocarcinoma, the IASLC grading system was significantly associated with disease-free survival (DFS) [hazard ratio (HR) = 1.419; 95 % confidence interval (CI): 1.040-1.937; P = 0.027] and overall survival (OS) (HR = 1.899; 95 % CI: 1.168-3.087; P = 0.010). In patients with IASLC Grades 1 and 2, the simultaneous presence of filigree micropapillary and discohesive growth pattern was significantly correlated with DFS (HR = 1.899; 95 % CI:1.168-3.087; P = 0.010). However, the filigree micropapillary and discohesive growth pattern did not affect the OS (HR = 2.786; P = 0.317). The competitive risk model revealed that in the stage I cohort, the simultaneous presence of filigree micropapillary and discohesive growth pattern was a risk factor for recurrence and metastasis [sub- distribution HR (SHR) = 1.987; 95 %CI: 1.122-3.518; P = 0.019].

CONCLUSION

Our study verified that the new prognostic stratification system was an effective stratification tool. Filigree micropapillary and discohesive growth pattern may also be risk factors for DFS, postoperative recurrence and metastasis.

Predictive Value of 18 F-FDG PET/MRI for Pleural Invasion in Solid and Subsolid Lung Adenocarcinomas Smaller Than 3 cm

BACKGROUND

Positron emission tomography (PET)/MRI combines the characteristics of metabolism imaging and high soft tissue resolution, and could provide high diagnostic efficacy for assessment of pleural invasion (PI) of lung cancer.

PURPOSE

To investigate the application of ¹⁸ F-fluorodeoxyglucose (FDG) PET/MRI for predicting PI of lung cancer with the maximum diameter ≤3 cm.

STUDY TYPE

Prospective.

POPULATION

A total of 44 patients with non-small cell lung cancer (NSCLC), age from 39 to 79 years old, including 19 (56.82%) females.

FIELD STRENGTH/SEQUENCE

A 3-T, hybrid PET/MRI including axial fast spin echo respiratory-triggered T2 fat-suppressed imaging (T2FS) and echo planar imaging diffusion-weighted imaging (DWI).

ASSESSMENT

The maximum standardized uptake value (SUVmax) of all lesions was measured on PET images. Localized effusion outside the contact between the nodules and the pleura on T2FS and signal at the contact between the nodules and the pleura on DWI were evaluated by experienced physicians through visual assessment of the MRI sequences.

STATISTICAL TESTS

Three models (models 1-3) were developed, incorporating CT, CT and PET, PET and MRI features, and Lasso regression was used in feature selection. The receiver operating characteristic (ROC) curve for PI diagnosis was visualized for each model, and the area under the curve (AUC) was calculated. The DeLong test was used to compare the different AUCs. A P value < 0.05 was considered statistically significant.

RESULTS

The AUC of models 1-3 was 0.762, 0.829, and 0.915, respectively. The DeLong test showed a statistically significant difference between the AUCs of model 1 vs. model 3, while the differences between the AUCs of model 1 vs. model 2 (P = 0.253) and model 2 vs. model 3 (P = 0.075) were not statistically significant.

DATA CONCLUSION

¹⁸ F-FDG PET/MRI might show high predictive value for lung adenocarcinoma smaller than 3 cm with PI.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 2.

Rethinking the Selection of Pathological T-Classification for Non-Small-Cell Lung Cancer in Varying Degrees of Visceral Pleural Invasion: A SEER-Based Study

Background

The T classification of non-small-cell lung cancer (NSCLC) was upgraded from T1 to T2 when accompanied by visceral pleural invasion (VPI). However, the association between VPI and prognostic outcomes was obscure in NSCLC patients with ≤3 cm tumor size (TS), which leaded the controversy of selection of T classification. The goal was to evaluate the effect of VPI on the prognosis of NSCLC with ≤ 3cm TS and present a modified T classification.

Methods

A total of 14,934 NSCLC patients without distant metastasis were recruited through a retrospective study in the SEER database. The effect of VPI on lung cancer specific survival (LCSS) was evaluated using survival curve and COX regression analysis in NSCLC patients with ≤3 cm TS.

Results

Although there was no difference of the LCSS of PL0 and PL1 patients with ≤2 cm TS in patients without lymph node (LN) metastasis, the LCSS was lower in PL2 patients than those in PL0 (T1a: p < 0.001; T1b: p = 0.001). Moreover, the LCSS was decreased in PL1 and PL2 patients with 2–3 cm TS compared with PL0 (T1c: PL1, p < 0.001; PL2, p = 0.009) of patients without LN metastasis. No difference of LCSS was observed in patients with LN metastasis between PL0 with PL1 and PL2.

Conclusion

In NSCLC patients without LN metastasis and TS ≤ 2 cm, tumor with PL1 should remain defined as T1, tumor with PL2 should be defined as T2. However, 2–3 cm TS patients with PL1 or PL2 should both defined as T2. Meanwhile, ≤3 cm TS patients with LN metastasis can be regarded as T1, whether NSCLC patients accompanied with PL1 or PL2.

Consolidation Tumor Ratio Combined With Pathological Features Could Predict Status of Lymph Nodes of Early-Stage Lung Adenocarcinoma

INTRODUCTION

Stage IA lung adenocarcinoma manifested as part-solid nodules (PSNs), has attracted immense attention owing to its unique characteristics and the definition of its invasiveness remains unclear. We sought to develop a nomogram for predicting the status of lymph nodes of this kind of nodules.

METHODS

A total of 2,504 patients between September 2018 to October 2020 with part-solid nodules in our center were reviewed. Their histopathological features were extracted from paraffin sections, whereas frozen sections were reviewed to confirm the consistency of frozen sections and paraffin sections. Univariate and multivariate logistic regression analyses and Akaike information criterion (AIC) variable selection were performed to assess the risk factors of lymph node metastasis and construct the nomogram. The nomogram was subjected to bootstrap internal validation and external validation. The concordance index (C-index) was applied to evaluate the predictive accuracy and discriminative ability.

RESULTS

We enrolled 215 and 161 eligible patients in the training cohort and validation cohort, respectively. The sensitivity between frozen and paraffin sections on the presence of micropapillary/solid subtype was 78.4%. Multivariable analysis demonstrated that MVI, the presence of micropapillary/solid subtype, and CTR >0.61 were independently associated with lymph node metastasis (p < 0.01). Five risk factors were integrated into the nomogram. The nomogram demonstrated good accuracy in estimating the risk of lymph node metastasis, with a C-index of 0.945 (95% CI: 0.916-0.974) in the training cohort and a C-index of 0.975 (95% CI: 0.954-0.995) in the validation cohort. The model's calibration was excellent in both cohorts.

CONCLUSION

The nomogram established showed excellent discrimination and calibration and could predict the status of lymph nodes for patients with ≤3 cm PSNs. Also, this prediction model has the prediction potential before the end of surgery.

The value of CT radiomics features to predict visceral pleural invasion in ≤3 cm peripheral type early non-small cell lung cancer

OBJECTIVE

To investigate predictive value of CT-based radiomics features on visceral pleural invasion (VPI) in ≤3.0 cm peripheral type early non-small cell lung cancer (NSCLC).

METHODS

A total of 221 NSCLC cases were collected. Among them, 115 are VPI-positive and 106 are VPI-negative. Using a stratified random sampling method, 70% cases were assigned to training dataset (n = 155) and 30% cases (n = 66) were assigned to validation dataset. First, CT findings, imaging features, clinical data and pathological findings were retrospectively analyzed, the size, location and density characteristics of nodules and lymph node status, the relationship between lesions and pleura (RAP) were assessed, and their mean CT value and the shortest distance between lesions and pleura (DLP) were measured. Next, the minimum redundancy-maximum relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) features were extracted from the imaging features. Then, CT imaging prediction model, texture feature prediction model and joint prediction model were built using multifactorial logistic regression analysis method, and the area under the ROC curve (AUC) was applied to evaluate model performance in predicting VPI.

RESULTS

Mean diameter, density, fractal relationship with pleura, and presence of lymph node metastasis were all independent predictors of VPI. When applying to the validation dataset, the CT imaging model, texture feature model, and joint prediction model yielded AUC = 0.882, 0.824 and 0.894, respectively, indicating that AUC of the joint prediction model was the highest (p < 0.05).

CONCLUSION

The study demonstrates that the joint prediction model containing CT morphological features and texture features enables to predict the presence of VPI in early NSCLC preoperatively at the highest level.

Nucleolin and nucleophosmin expression patterns in pulmonary adenocarcinoma invading the pleura and in pleural malignant mesothelioma

BACKGROUND

Visceral pleural invasion (VPI) in adenocarcinoma of the lung is considered a poor prognostic factor. The purpose of this study was to analyze nucleolin and nucleophosmin expression in pulmonary adenocarcinoma (PA) with VPI and in pleural malignant mesothelioma.

METHODS

The study was conducted on the basis of 19 pathologically-confirmed cases of adenocarcinoma of the lung and 29 cases of epithelioid malignant mesothelioma. The nucleolin and nucleophosmin expression was assessed immunohistochemically and analyzed with image analysis software.

RESULTS

Nucleolin expression was lower while nucleophosmin was higher in pleural invasion of pulmonary adenocarcinoma than in the central part of the tumor. Differences in subpopulations of cells with different expression of proteins studied were also found. Malignant mesothelioma showed lower nucleolin expression than adenocarcinoma of the lung but no differences in nucleophosmin expression were found.

CONCLUSIONS

The results of our study suggested that lower nucleolin and higher nucleophosmin expression may be related to higher invasiveness of adenocarcinoma of the lung. Differences in nucleolin expression between pulmonary adenocarcinoma and malignant mesothelioma indicate another aspect of biology of these pleura-invading cancers that requires further study.

KEY POINTS

SIGNIFICANT FINDINGS OF THE STUDY: Differences in nucleolin and nucleophosmin expression in pleura invading pulmonary adenocarcinoma indicate the involvement of these proteins in its locoregional spread while differences in nucleolin expression between pulmonary adenocarcinoma and malignant mesothelioma suggest another aspect of biology of these cancers.

WHAT THIS STUDY ADDS

This is the first study on nucleolin and nucleophosmin expression in pleural malignant mesothelioma and pleura-invading pulmonary adenocarcinoma. Our findings may assist in understanding the mechanisms of locoregional spread of adenocarcinoma and differences between these two pleura-invading cancers.

Integration of multiple key molecules in lung adenocarcinoma identifies prognostic and immunotherapeutic relevant gene signatures

BACKGROUND

Although multiple key molecules in lung adenocarcinoma (LUAD) have been identified in recent years, the overall tumor microenvironment (TME) immune cell infiltration characterizations mediated by multiple key molecules remain little known. This study aimed to integrate the roles of multiple key molecules to evaluate patient prognosis and TME cell infiltration characterization as well as responses to immunotherapy.

METHODS

Using combined LUAD cancer cohorts with 228 normal samples and 913 tumor samples, we comprehensively dissected the differences of genomic and TME cell infiltration landscapes between normal lung tissues and tumor tissues. The single-sample gene-set enrichment analysis (ssGSEA) was used to quantify the relative abundance of 24 cell infiltration. The riskScore signature was constructed using a least absolute shrinkage and selection operator (LASSO) Cox regression mode.

RESULTS

Seven novel key molecules with significantly up-regulated expression in LUAD were determined. Survival analyses revealed their important prognostic values. LUAD microenvironment presented a markedly decreased infiltration of immune cells compared to normal lung tissues. We found tumors with up-regulated expression of these key molecules exhibited a significantly decreased TME cell infiltration and increased immune checkpoint molecule expression. The high riskScore subtype was characterized by decreased innate and adaptive immune cell infiltration. Activation of p53 signaling pathway and regulator T cells were observed in the high riskScore subtype, which were regarded as T-cell suppressive and could be responsible for poorer prognosis in this subtype (HR 1.83(1.27-2.63)). Multivariate analyses demonstrated the riskScore was a robust and independent prognostic biomarker, and its value in predicting immunotherapeutic outcomes was also confirmed (HR 1.70(1.22-2.37)).

CONCLUSIONS

This study reveal a novel gene signature significantly related to patient prognosis and TME cell infiltration in LUAD. We demonstrated the integrated roles of multiple key molecules played a crucial role in shaping TME cell infiltration diversity and complexity. Evaluating the integrated characterization of multiple key molecules could contribute to predicting patients' response to immunotherapy and guiding more effective immunotherapy strategies.

[Effect of Apatinib on Invasion and Migration of Lung Cancer Cells and Its Mechanism]

背景与目的

肺癌是世界上对人类健康产生重大危害的癌症之一，近年来靶向治疗的效果日益显著。阿帕替尼（Apatinib, YN968D1）是目前研究较热的多靶点抗肿瘤药物，本研究旨在探讨Apatinib对肺癌细胞生物学特性的影响和其可能的作用机制。

方法

体外培养肺腺癌细胞株H1299与H3255，CCK法、划痕实验及Transwell实验检测Apatinib对H1299与H3255细胞增殖、迁移及侵袭的影响，Western blot检测肿瘤血管生成和侵袭相关蛋白的表达。

结果

Apatinib显著抑制H1299与H3255的增殖、迁移及侵袭能力，并呈浓度依赖性。Western blot显示，随药物浓度增加，VEGF、VEGFR2、N-cadherin、MMP9、MMP2、Vimentin表达下调，E-cadherin表达上调。

结论

Apatinib可抑制肺腺癌细胞H1299、H3255的侵袭迁移能力，其机制可能通过调控上皮-间充质转化及基质金属蛋白酶相关蛋白的表达来实现。