Molecular classification of pulmonary sarcomatoid carcinomas suggests new therapeutic opportunities.

BACKGROUND: Pulmonary sarcomatoid carcinoma (SC) is a rare disease with poor prognosis and with strong inter- and intratumor heterogeneity. However, molecular classification is currently focused on activating MET mutations. We sought to better characterize the molecular diversity of SC using mutational signatures that reflect different mutational processes, such as tobacco-associated adducts (signature 4), BRCA1/BRCA2 deficiency (signature 3), or APOBEC enzyme deamination (signatures 2 and 13). PATIENTS AND METHODS: Whole-exome sequencing was carried out in 15 SC patients and on data from 10 previously published cases. Hierarchical clustering and consensus non-negative matrix factorization were carried out for samples classification based on mutational signatures. RESULTS: In the two series, SC distributed between two clusters (C): Csig4 (characterized by signature 4) and Csig2-3-13 (signatures 2, 3, and 13). Csig4 exhibited more frequent MAPK pathway mutations than Csig2-3-13 (pooled series: n = 10/14 versus 2/11, P < 0.05, respectively) and stronger PD-L1 expression (our series: n = 6/9 versus 1/6, P = 0.12). MET alterations were only found in Csig2-3-13 (pooled series: n = 5/11 versus 0/14, P = 0.009), as well as BRCA1/BRCA2 (n = 3/11 versus 0/15), EGFR (n = 1), and IDH1 (n = 1) mutations. Csig2-3-13 patients had better overall survival than Csig4 patients (median: >45 versus 7 months, respectively, P = 0.001). CONCLUSIONS: Our study suggests that SC presents at least two clusters comprising different mutational processes, gene alterations, and PD-L1 expression. New potential treatment possibilities are immune checkpoint inhibitors in Csig4 and specific targeted agents in Csig2-3-13. These findings should encourage clinicians to conduct broad molecular and immunological testing in SC patients beyond MET exon 14 alterations.

[Role of the Sonic Hedgehog pathway in thoracic cancers]. / Rôle de la voie Sonic Hedgehog dans les cancers thoraciques.

INTRODUCTION: Sonic Hedgehog (Shh) pathway is physiologically activated during embryogenesis and development. It plays a role in idiopathic lung fibrosis and is also activated in several solid cancers. STATE OF THE ART: Shh pathway is reactivated in thoracic cancers, as small cell lung carcinoma, non-small cell lung carcinoma and malignant pleural mesothelioma. Shh pathway is associated with cancer stem cells and seems to have a crucial role in tumor proliferation, aggressiveness and chemoresistance in these cancers. This review describes the activation mode of Shh pathway in thoracic cancers and its role in small cell lung carcinoma, non-small cell lung carcinoma and malignant pleural mesothelioma, using in vitro and in vivo models. Notably, data from literature show that inhibition of Shh pathway has an antitumor action and sensitizes to chemotherapy. PERSPECTIVES: These results incite to develop targeted therapies against Shh pathway in the treatment of thoracic cancers.

Clinical and molecular features in patients with advanced non-small-cell lung carcinoma refractory to first-line platinum-based chemotherapy.

Most of the cases of non-small-cell lung cancer (NSCLC) are diagnosed at an advanced stage and are treated with platinum-doublet chemotherapy. However, some patients are refractory to this treatment. The aim of this study was to identify the clinical and molecular characteristics of patients with refractory disease. All consecutive patients between 2003 and 2006, who received a platinum-doublet chemotherapy as first-line treatment for stage IIIb-IV NSCLC, were included. Refractory patients were defined as early progressive disease (PD) at the first evaluation of chemotherapy according to WHO criteria. The clinical, histo-pathological, and molecular characteristics (EGFR: exon 19, 20, 21 and KRAS: exon 2 by PCR sequencing; ALK by immunohistochemistry) and survival of refractory patients with initial PD (r-patients) and controlled disease (c-patients) were compared by univariate analyses. Factors that differed between the two groups (p-value <0.25 in univariate analyses) were entered into multivariate analysis. In this study, 178 patients were included. The first tumor assessment was carried out after a median of three cycles (range 1-4). Forty-six (25.8%) patients were refractory. Clinical presentation was similar between r- and c-patients. The sarcomatoid histological subtype was more common in r-patients than c-patients (10.9% vs. 1.5%, respectively; p=0.057). The proportion of EGFR (5.2% vs. 9.6%, p=0.224) and KRAS mutations (11.1% vs. 5.7%, p=0.357), and the expression of ALK (6.3% vs. 2.5%, p=0.327) did not differ significantly between the two groups. In multivariate analysis, sarcomatoid histological subtype was the only factor associated with early PD (OR=7.50; 95%CI: 1.02-55.45; p=0.048). r-Patients had significantly shorter survival than c-patients (median 5 months (IQR 3.2-9.9) vs. 15.4 months (IQR 9.9-22.5), respectively; p<0.0001). In conclusion, patients with early PD under platinum-doublet chemotherapy had shorter survival than c-patients. Sarcomatoid histological subtype was the only independent factor associated with early PD.

Upregulation of bronchioloalveolar carcinoma-derived C-X-C chemokines by tumor infiltrating inflammatory cells.

OBJECTIVE AND DESIGN: The presence of increased numbers of tumor-infiltrating neutrophils is associated with poorer outcome in patients with adenocarcinoma of the bronchioloalveolar (BAC) subtype. We evaluated the role of inflammatory environment on C-X-C chemokine tumor production. MATERIALS: Bronchoalveolar lavage from 31 consecutive patients with adenocarcinoma of the BAC subtype as well as tumor and normal pulmonary tissue samples. A549 BAC cell line. Peripheral blood mononuclear cells (PBMC), polymorphonuclear neutrophils (PMN) and alveolar macrophages (AM). METHODS: Elisa measurements and immunohistochemical studies of ENA-78, IL-8, IL-1beta and TNF-alpha. RNA isolation, reverse transcription, and PCR amplification of ENA-78 and IL-8. RESULTS: C-X-C peptides were expressed by tumor cells of all the tumor specimens tested. ENA-78 and IL-8 were also expressed by AM. To better understand the regulation of the C-X-C production, BAC cell line was cultured alone or with inflammatory cells. PBMC upregulated both tumor ENA-78 and IL-8 mRNA expression and protein release whereas AM only upregulated ENA-78 mRNA expression and protein release; PMN had no effect. Anti-human IL-1beta antibodies (ab) inhibited the A549 ENA-78 and IL-8 production stimulated by PBMC-CM. Anti-human TNF-alpha ab inhibited A549 ENA-78 production stimulated by AM-CM. IL-1beta and TNF-alpha were expressed in vivo by inflammatory cells, although TNF-alpha was also expressed by tumor cells. CONCLUSIONS: This work emphasizes the role of the host inflammatory response in promoting tumor growth in vivo.

Tumor-derived granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor prolong the survival of neutrophils infiltrating bronchoalveolar subtype pulmonary adenocarcinoma.

We evaluated the role of the tumor environment in the regulation of apoptosis of tumor-infiltrating neutrophils, the number of which correlates negatively with outcome, in patients with adenocarcinoma of the bronchioloalveolar (BAC) subtype. We examined three different parameters of apoptosis, namely morphological aspect, annexin-V expression, and DNA fragmentation. Bronchoalveolar lavage fluid (BALF) supernatants from patients with BAC significantly inhibited the 24-hour spontaneous apoptosis of normal peripheral blood neutrophils in vitro compared to BALF supernatants from control patients (64 +/- 4% versus 90 +/- 2% measured by annexin-V flow cytometry, P = 0.04). The alveolar neutrophil count correlated positively with the granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) concentrations in the patient's BALF. Furthermore, neutralizing antibodies (Abs) against GM-CSF and G-CSF significantly inhibited BALF anti-apoptotic activity (15 to 40% and 34 to 63% inhibition, respectively), whereas neutralizing Abs against interleukin (IL)-8, IL-6, IL-1beta and tumor necrosis factor-alpha had no significant effect. In an attempt to identify the cell origin of anti-apoptotic cytokines, we tested in vitro the effect of BAC cells (A549 cell line and primary culture derived from a patient's BAC tumor) on the apoptosis of peripheral blood neutrophils. Cell-free supernatants from tumor cells did not inhibit neutrophil apoptosis. In contrast, cell-free supernatants from tumor cells previously exposed to conditioned media from peripheral blood mononuclear cells and alveolar macrophages significantly inhibited spontaneous neutrophil apoptosis. This inhibition was partially lifted when conditioned media from mononuclear cells were previously treated with Abs against IL-1beta and tumor necrosis factor-alpha. As in vivo, neutralizing Abs against GM-CSF significantly inhibited the anti-apoptotic activity of cell culture supernatants, and combination with Abs against G-CSF had an additive effect. In vivo, GM-CSF and G-CSF were strongly expressed by tumor cells and moderately or not expressed by the normal epithelium, as assessed by immunohistochemical studies. These findings demonstrate that the tumor environment generates local conditions that prolong alveolar neutrophil survival through the production of soluble factors, thereby contributing to the persistence of the neutrophil alveolitis observed in BAC.