Search

The anti-tumor immune response is greatly hindered by the protumor polarization of tumor-associated macrophages (TAMs). Cancer-related inflammation plays a central role in TAMs protumor polarization. Our study explored the unique positive feedback loop between inflammasome and complement in TAMs. The present study identified NOD-like receptors family pyrin domain containing 12 (NLRP12) formed positive feedback with C1qA and drove TAMs protumor polarization via the LILRB4/NF-κB pathway. In addition, NLRP12 was predominantly expressed in TAMs and was associated with poorer prognosis in lung adenocarcinoma (LUAD) patients. Knocking down LILRB4 inhibited TAMs protumor polarization. NLRP12-overexpressing TAMs promoted tumor cells' malignant progression and inhibited T cells' proliferation and cytotoxic function. Lastly, NLRP12 knockout (NLRP12 -/- ) reversed macrophage polarization, enhanced T-cell anti-tumor immunity, and suppressed tumor growth. Our findings highlighted the essential role of NLRP12/C1qA positive feedback loop and the LILRB4/NF-κB pathway in promoting TAMs protumor polarization. Inhibition of NLRP12 suppressed tumor development and promoted immune response. NLRP12 may be a promising target for LUAD immunotherapy., Competing Interests: Declarations Conflict of interest The authors declare no conflict of interests. Ethical approval All animal experiments were approved by the Committee of Animal Care and Use of Renmin Hospital of Wuhan University, under the consent number WDRM 20240405B, and were performed following the Guide for the Care and Use of Laboratory Animals. Consent to publish Not applicable., (© 2024. The Author(s).)

Immune checkpoint inhibitor (ICI) rechallenge in non-small cell lung cancer (NSCLC) is a promising therapeutic strategy. The situation for ICI rechallenge can be divided into three categories: adverse events (AEs); resistance to ICIs, and rechallenge becomes compulsive because of tumor relapse while the patients had completed a 2 year course of immunotherapy. However, these categories are still controversial and should be explored further. Through voting at the 6th Straits Summit Forum on Lung Cancer, in this study we summarize the consensus of 147 experts in ICI rechallenges. A total of 97.74% experts agreed to rechallenge; 48.87% experts rechallenge with the original drug, and the others rechallenge with a different drug; 40.3% agreed to rechallenge directly after progression; 88.06% experts agreed to ICI rechallenge with a combination regimen; and factors such as previous performance status score, PD-1 expression, and age should also be considered. Understanding the the clinical studies in ICI rechallenge could bring us one step closer to understanding the consensus. In patients with advanced NSCLC who have suffered recurrent or distant metastasis after immunotherapy, the option of rechallenge with ICIs is a promising treatment option., (© 2024 The Authors. Thoracic Cancer published by John Wiley & Sons Australia, Ltd.)

Immune checkpoint inhibitors (ICIs) have improved the long-term survival of NSCLC patients. However, the efficacy of ICIs in elderly NSCLC patients remains controversial. We conducted a retrospective study and meta-analysis exploring the efficacy of ICIs in those patients using public databases and RCTs. NSCLC patients were identified into elderly and non-elderly groups by age 75 years. The retrospective study showed significant differences in OS and PFS between non-elderly and elderly patients treated with ICIs (P= 0.029 and 0.027), with reduced efficacy in elderly NSCLC patients. ECOG PS also negatively affected OS in elderly NSCLC patients (P= 0.007). In meta-analysis, the HR for OS in the non-elderly and elderly groups were 0.74 and 0.90, respectively, and the difference between the two age groups was statistically significant (P= 0.025). ICIs resulted in a lower incidence of all-grade (OR= 0.47) and high-grade TRAEs (OR= 0.38) than chemotherapy. Our findings revealed that the survival benefit of ICIs in elderly patients (≥ 75 years) may be lower than in non-elderly patients. In addition, the incidence of TRAEs induced by ICIs was lower than chemotherapy.

Immune checkpoint inhibitors (PD-1/PD-L1 and CTLA-4 blockade) have revolutionized the treatment landscape in non-small cell lung cancer (NSCLC). Secondary resistance to immunotherapy (IO), which poses a substantial challenge in clinical settings, occurs in several initial responders. Currently, new treatment approaches have been extensively evaluated in investigational studies for these patients to tackle this difficult problem; however, the lack of consistency in clinical definition, uniform criteria for enrollment in clinical trials, and interpretation of results remain significant hurdles to progress. Thus, our expert panel comprehensively synthesized data from current studies to propose a practical clinical definition of secondary resistance to immunotherapy in NSCLC in metastatic and neoadjuvant settings. In addition to patients who received IO alone (including IO-IO combinations), we also generated a definition for patients treated with chemotherapy plus IO. This consensus aimed to provide guidance for clinical trial design and facilitate future discussions with investigators. It should be noted that additional updates in this consensus are required when new data is available., (© 2023 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Our previous study demonstrated that the overexpression of solute carrier family 22 member 18 (SLC22A18) in human non-small cell lung cancer (NSCLC) tissues might be associated with tumor progression and patients' prognosis. The aim of this study was to investigate the molecular mechanisms underlying its roles in NSCLC. As a result, bioinformatics analysis and luciferase reporter assay showed that microRNA (miRNA)-137 directly targeted SLC22A18 in NSCLC cells. Then, functional studies indicated that the ectopic expression of miR-137 significantly inhibited NSCLC cell proliferation, invasion and migration by targeting SLC22A18. More importantly, the decreased expression of miR-137 in clinical NSCLC tissues was correlated with advanced TNM stage, positive metastasis and poor prognosis of patients with this malignancy. In conclusion, these findings offer the convincing evidence that the roles of SLC22A18 in NSCLC progression may be partially caused by the regulatory effects of miR-137, which may function as a tumor suppressor. Our clinical data further indicated that miR-137 may be an independent favorable prognostic factor in NSCLC patients., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Previous study has revealed that tumor-associated macrophages (TAMs) correlate with response to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) in advanced non-small cell lung cancer (NSCLC). In the present study, we further determined that M2-TAMs, but not M1-TAMs, are related to the treatment response to EGFR-TKIs in advanced NSCLC and may be an independent predictor of survival. Eighty-eight advanced lung adenocarcinoma patients treated with a second-line EGFR-TKI were involved in this study. M2-TAMs counts but not M1-TAMs were significantly higher in patients with progressive disease than in those without (P < 0.001). A trend also remained in patients with known EGFR status (n = 61) and those with mutant EGFR (n = 49). High M2-TAMs counts were shown to be significantly related to poor progression-free survival (PFS) and overall survival (OS) in all patients, or subsets of patients with known EGFR status or patients with EGFR mutation (all P < 0.05). Multivariate Cox analyses showed that high M2-TAMs counts and EGFR mutations were both independent factors associated with PFS and OS (P < 0.05). Overall, we revealed that M2- but not M1-TAMs are related to the response of EGFR-TKIs treatment irrespective of EGFR mutation and can independently predict survival in advanced lung adenocarcinoma treated with a second-line EGFR-TKI.

Objectives: Tumor-associated macrophages that generally exhibit an alternatively activated (M2) phenotype have been linked to tumor progression and metastasis. However, the role of M2-polarized macrophages in the growth and metastasis of lung adenocarcinoma remains enigmatic. The aim of this study was to explore the effect of M2 macrophages on the proliferation and migration of mouse Lewis lung carcinoma cells and tumor-induced lymphangiogenesis., Methods: Trypan blue staining and the Transwell migration assay were performed to evaluate the effects of activated (M1 or M2) macrophages on the proliferation and migration of Lewis cells. Furthermore, vascular endothelial growth factor-C expression in Lewis cells and nitric oxide secretion from activated macrophages were detected during the co-culture assay. Following treatment with activated macrophages, lymphatic endothelial cells differentiated into capillary-like structures, and the induction of Lewis cell migration was assessed using a two-dimensional Matrigel-based assay., Results: In the co-culture Transwell system, the proliferation and migration of Lewis cells were promoted by M2 macrophages. Moreover, the co-culture significantly increased the expression of vascular endothelial growth factor-C by Lewis cells and reduced the secretion of nitric oxide from M2 macrophages, which subsequently led to the capillary morphogenesis of lymphatic endothelial cells. Interestingly, following co-culture with Lewis cells, the function of RAW264.7 cells was polarized toward that of the M2 macrophage phenotype., Conclusion: M2-polarized macrophages promoted the metastatic behavior of Lewis cells by inducing vascular endothelial growth factor-C expression. Thus, the interruption of signaling between M2 macrophages and Lewis cells may be considered to be a new therapeutic strategy.

Antisense oligonucleotide (ASODN) targeting specific gene can be capable of potently downregulating proliferation and invasion in human cancer cells. However, the underlying mechanisms are less well defined. Here the authors show that matrix metalloproteinase-7 (MMP-7) ASODN changes the ultrastructure of human A549 lung adenocarcinoma cells. Transfection of MMP-7 ASODN significantly lowered the expression of MMP-7 protein in A549 cells. Decreased microvilli, endoplasmic reticulum dilation, swelling of mitochondria, and formation of apoptotic bodies were observed by transmission electron microscope. Collectively, the findings identified the morphological mechanism that MMP-7 ASODN inhibited proliferation and invasion in A549 cells.

Objectives: Tumor-associated macrophages have been implicated in promoting tumor growth, progression and metastasis. However, the activated phenotype (M1 or M2) of tumor-associated macrophages remains unknown in solid tumors. Therefore, this study examined the density and prognostic significance of M2-polarized tumor-associated macrophages in lung adenocarcinoma., Methods: Tumor specimens from 65 lung adenocarcinoma patients were assessed by ELISA for Th1/Th2 cytokine concentrations. The activated phenotype (M1 or M2) of tumor-associated macrophages was determined utilizing immunofluorescence staining. Additionally, to evaluate lymphangiogenesis, peritumoral lymphatic microvessel density was measured using D2-40. The correlation between tumor-associated macrophage subtype and overall patient survival was analyzed using the Kaplan-Meier method and compared using the log-rank test., Results: A shift toward Th2 cytokine expression was detected within lung adenocarcinoma microenvironments. Approximately 79.71±16.27% of tumor-associated macrophages were M2 polarized; the remaining 20.35±5.31% were M1 polarized. The infiltration of M2-polarized macrophages was significantly associated with P-TNM staging and lymph node metastasis. The peritumoral lymphatic microvessel density was significantly higher in the high M2-polarized tumor-associated macrophage group than in the low M2-polarized tumor-associated macrophage group. A significant difference in overall patient survival was detected not only between patients with tumors with high and low macrophage counts but also between patients with tumors with high and low counts of M2-polarized macrophages., Conclusion: Tumor-associated macrophages in lung adenocarcinoma have an M2-polarized subtype and are associated with poor prognoses, perhaps resulting from accelerated lymphangiogenesis and lymph node metastasis.

The expression levels of the RNA-binding protein Hu antigen (HuR) and vascular endothelial growth factor-C (VEGF-C) were examined immunohistochemically in 81 non-small cell lung cancers (NSCLC) and 15 benign human lung tissues. HuR showed a nuclear overexpression in 82.7% (67/81) of NSCLC specimens. Cytoplasmic immunoreactivity for HuR was observed in 45.7% (37/81) of NSCLC, while only nuclear expression of HuR was observed in 13.3% (2/15) of benign lung tissues. The expression of VEGF-C was present in a subgroup of 70.4% (57/81) of tumor cases. In the human NSCLC samples, cytoplasmic but not nuclear HuR expression was significantly associated with increased levels of VEGF-C and with clinicopathological variables, including high tumor grade, poor differentiation and lymph node metastasis. In vitro, HuR showed a predominantly nuclear staining in Lewis lung cancer cells, as seen by confocal microscopy. When lung cancer cells were treated with siRNA targeted against HuR, expression levels of the HuR and VEGF-C proteins were significantly reduced, as seen by Western blotting. Our findings indicate that there is a dysregulation of the cellular distribution of the mRNA stability factor HuR in a subset of NSCLC. Examination of cytoplasmic HuR in NSCLC tissues will allow for valuable prognostic diagnosis of lymph node metastasis, as HuR might be an important mediator regulating the expression of VEGF-C., (Copyright 2009 S. Karger AG, Basel.)