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Large cell carcinoma (LCC) is a rare and aggressive lung cancer subtype with poor prognosis and no targeted therapies. Tumor-associated fibroblasts (TAFs) derived from LCC tumors exhibit premature senescence, and coculture of pulmonary fibroblasts with LCC cell lines selectively induces fibroblast senescence, which in turn drives LCC cell growth and invasion. Here we identify MMP1 as overexpressed specifically in LCC cell lines, and we show that expression of MMP1 by LCC cells is necessary for induction of fibroblast senescence and consequent tumor promotion in both cell culture and mouse models. We also show that MMP1, in combination with TGF-ß1, is sufficient to induce fibroblast senescence and consequent LCC promotion. Furthermore, we implicate PAR-1 and oxidative stress in MMP1/TGF-ß1-induced TAF senescence. Our results establish an entirely new role for MMP1 in cancer, and support a novel therapeutic strategy in LCC based on targeting senescent TAFs.

Purpose: We aimed to maximize the performance of detecting genetic alterations in lung cancer using high-throughput sequencing for patient-derived xenografts (PDXs). Experimental Design: We undertook an integrated RNA and whole-exome sequencing of 14 PDXs. We focused on the genetic and functional analysis of beta 2-microglobulin (B2M), a component of the HLA class-I complex. Results: We identified alterations in genes involved in various functions, such as B2M involved in immunosurveillance. We extended the mutational analysis of B2M to about 230 lung cancers. Five percent of the lung cancers carried somatic mutations, most of which impaired the correct formation of the HLA-I complex. We also report that genes such as CALR, PDIA3, and TAP1, which are involved in the maturation of the HLA-I complex, are altered in lung cancer. By gene expression microarrays, we observed that restitution of B2M in lung cancer cells upregulated targets of IFN alpha/IFN gamma. Furthermore, one third of the lung cancers lacked the HLA-I complex, which was associated with lower cytotoxic CD8(+) lymphocyte infiltration. The levels of B2M and HLA-I proteins correlated with those of PD-L1. Finally, a deficiency in HLA-I complex and CD8(+) infiltration tended to correlate with reduced survival of patients with lung cancer treated with anti-PD-1/anti-PD-L1. Conclusions: Here, we report recurrent inactivation of B2M in lung cancer. These observations, coupled with the mutations found at CALR, PDIA3, and TAP1, and the downregulation of the HLA-I complex, indicate that an abnormal immunosurveillance axis contributes to lung cancer development. Finally, our observations suggest that an impaired HLA-I complex affects the response to anti-PD-1/anti-PD-L1 therapies. (C) 2016 AACR.

In lung cancer, CD133+ cells represent the subset of cancer stem cells (CSC) able to sustain tumor growth and metastatic dissemination. CSC function is tightly regulated by specialized niches composed of both stromal cells and extracellular matrix (ECM) proteins, mainly represented by collagen. The relevance of collagen glycosylation, a fundamental post‐translational modification controlling several biological processes, in regulating tumor cell phenotype remains, however, largely unexplored. To investigate the bioactive effects of differential ECM glycosylation on lung cancer cells, we prepared collagen films functionalized with glucose (Glc‐collagen) and galactose (Gal‐collagen) exploiting a neoglycosylation approach based on a reductive amination of maltose and lactose with the amino residues of collagen lysines. We demonstrate that culturing of tumor cells on collagen determines a glycosylation‐dependent positive selection of CSC and triggers their expansion/generation. The functional relevance of CD133+ CSC increase was validated in vivo, proving an augmented tumorigenic and metastatic potential. High expression of integrin β1 in its active form is associated with an increased proficiency of tumor cells to sense signaling from glycosylated matrices (glyco‐collagen) and to acquire stemness features. Accordingly, inhibition of integrin β1 in tumor cells prevents CSC enrichment, suggesting that binding of integrin β1 to Glc‐collagen subtends CSC expansion/generation. We provide evidence suggesting that collagen glycosylation could play an essential role in modulating the creation of a niche favorable for the generation and selection/survival of lung CSC. Interfering with this crosstalk may represent an innovative therapeutic strategy for lung cancer treatment., Glycans are well known for their involvement in recognition phenomena between cells; however, the role of small glycan epitopes in cell–extracellular matrix (ECM) interactions needs to be further elucidated. Here we exploit bioactive ECM mimetics, functionalizing type I collagen films with different glycans, to investigate the relevance of specific ECM glycosignatures in tumor‐ECM interactions. We show that in vitro culturing of lung cancer cells on glycosylated collagen films results in differential modulation of cancer stem cells (CSC), associated in vivo with an enhanced tumor initiation ability and increased metastatic potential. Interactions of CSC with glycosylated collagen are regulated through the active form of integrin β1. Interfering with integrin β1 signaling results in abrogation of CSC enrichment induced by glycosylated collagen.

Platinum-based chemotherapy remains widely used in advanced non-small cell lung cancer (NSCLC) despite experimental evidence of its potential to induce long-term detrimental effects, including the promotion of pro-metastatic microenvironments. In this study, we investigated the interconnected pathways underlying the promotion of cisplatin-induced metastases. In tumor-free mice, cisplatin treatment resulted in an expansion in the bone marrow of CCR2+CXCR4+Ly6Chigh inflammatory monocytes (IMs) and an increase in lung levels of stromal SDF-1, the CXCR4 ligand. In experimental lung metastasis assays, cisplatin-induced IMs promoted the extravasation of tumor cells and the expansion of CD133+CXCR4+ metastasis-initiating cells (MICs). Peptide R, a novel CXCR4 inhibitor designed as an SDF-1 mimetic peptide, prevented cisplatin-induced IM expansion, the recruitment of IMs into the lungs, and the promotion of metastasis. At the primary tumor site, cisplatin treatment reduced tumor size while simultaneously inducing tumor release of SDF-1, MIC expansion, and recruitment of pro-invasive CXCR4+ macrophages. Co-recruitment of MICs and CCR2+CXCR4+ IMs to distant SDF-1-enriched sites also promoted spontaneous metastases that were prevented by CXCR4 blockade. In clinical specimens from NSCLC patients SDF-1 levels were found to be higher in platinum-treated samples and related to a worse clinical outcome. Our findings reveal that activation of the CXCR4/SDF-1 axis specifically mediates the pro-metastatic effects of cisplatin and suggest CXCR4 blockade as a possible novel combination strategy to control metastatic disease.

miRNAs play a central role in the complex signaling network of cancer cells with the tumor microenvironment. Little is known on the origin of circulating miRNAs and their relationship with the tumor microenvironment in lung cancer. Here, we focused on the cellular source and relative contribution of different cell types to circulating miRNAs composing our risk classifier of lung cancer using in vitro/in vivo models and clinical samples. A cell‐type specific expression pattern and topography of several miRNAs such as mir‐145 in fibroblasts, mir‐126 in endothelial cells, mir‐133a in skeletal muscle cells was observed in normal and lung cancer tissues. Granulocytes and platelets are the major contributors of miRNAs release in blood. miRNAs modulation observed in plasma of lung cancer subjects was consistent with de‐regulation of the same miRNAs observed during immunosuppressive conversion of immune cells. In particular, activated neutrophils showed a miRNA profile mirroring that observed in plasma of lung cancer subjects. Interestingly mir‐320a secreted by neutrophils of high‐risk heavy‐smokers promoted an M2‐like protumorigenic phenotype through downregulation of STAT4 when shuttled into macrophages. These findings suggest a multifactorial and nonepithelial cell‐autonomous origin of circulating miRNAs associated with risk of lung cancer and that circulating miRNAs may act in paracrine signaling with causative role in lung carcinogenesis and immunosuppression., What's new? microRNAs play a central role in the complex signaling network of cancer cells with the tumor microenvironment. However, little is known on the origin of circulating miRNAs and their mechanisms of action. This study found a multifactorial and non‐epithelial cell‐autonomous origin of circulating miRNAs associated with lung cancer risk. The findings also suggest a link between an immunosuppressive and pro‐tumorigenic microenvironment and modulation of circulating miRNAs associated with lung cancer risk. The authors propose a novel mechanism whereby miRNA released by neutrophils induce macrophage polarization to support lung cancer growth, highlighting the potential for reprogramming macrophages toward an anti‐tumor polarization.

PURPOSE: Lung cancer heterogeneity makes response to therapy extremely hard to predict. Patient-derived xenografts (PDXs) represent a reliable preclinical model that closely recapitulates the main characteristics of the primary tumor and could represent a useful asset to test new therapies. Here, using PET imaging, we verify how lung cancer PDXs reproduce the metabolic features of the corresponding primary tumors. METHODS: We performed longitudinal [18F]FDG-PET studies on nine different PDXs, obtained by implants of primary cancer fragments harvested from patients. Max [18F]FDG uptake values of the lesion for each group were calculated and compared to corresponding patient's uptake. RESULTS: Different PDXs showed variable tumor growth rate and [18F]FDG uptake confirming the preservation of individual characteristics. A good intra-group reproducibility of PET measurements was observed. Furthermore, the subgroup of PDXs originating from primary tumors with higher metabolic rate displayed a rank order of [18F]FDG uptake similar to that of patients' original SUV. CONCLUSION: PDXs reproduced the original glucose metabolism of primary lesions and represent therefore a promising preclinical model also for the early assessment of therapy efficacy.

Inactivation of the FHIT and TP53 genes is frequently observed in primary non-small cell lung cancers (NSCLC) and cell lines and may contribute to resistance to apoptotic stimuli elicited by various anti-tumor drugs. To evaluate a possible relationship between FHIT and TP53 status and response to platinum-analogue regimens, we retrospectively selected 55 NSCLC patients treated with carboplatin/gemcitabine. Pre-treatment formalin fixed biopsies were analyzed for FHIT and p53 protein expression by immunohistochemistry and representative micro dissected tissue for TP53 mutations by DG-DGGE/sequencing. The FHIT-negative immunophenotype (FHIT-, pathologic) was found in 33 patients (60%) and p53 over expression/mutation (p53+, pathologic) in 25 patients (45%). The FHIT-/p53+ combination was present in 12 patients (22%). Overall, there was partial response in 21 patients (38%), with subgroup response rates of 33% in FHIT+/p53-, 46% in FHIT+/p53+, 38% in FHIT-/p53- and 33% in FHIT-/p53+ patients. Median progression-free survival (PFS) was 9.6, 7.9, 6.8 and 5.9 months and median overall survival (OS) was 12.8, 11.9, 10.5 and 8.7 months in the four groups, respectively. The Group comparison showed significantly worse PFS (p=0.04) in FHIT-/p53+ than the other groups. There was no significant difference in OS between the groups. A trend (p=0.07) for shorter OS was found in FHIT- cases suggesting that NSCLC tumors carrying this feature are less responsive to treatment. This retrospective study indicates that FHIT-/p53+ status might be a biological variable influencing the efficacy of carboplatin/gemcitabine treatment in NSCLC.