The strategic roles of four enzymes in the interconnection between metabolism and oncogene activation in non-small cell lung cancer: Therapeutic implications.

NSCLC is the leading cause of cancer mortality and represents a major challenge in cancer therapy. Intrinsic and acquired anticancer drug resistance are promoted by hypoxia and HIF-1α. Moreover, chemoresistance is sustained by the activation of key signaling pathways (such as RAS and its well-known downstream targets PI3K/AKT and MAPK) and several mutated oncogenes (including KRAS and EGFR among others). In this review, we highlight how these oncogenic factors are interconnected with cell metabolism (aerobic glycolysis, glutaminolysis and lipid synthesis). Also, we stress the key role of four metabolic enzymes (PFK1, dimeric-PKM2, GLS1 and ACLY), which promote the activation of these oncogenic pathways in a positive feedback loop. These four tenors orchestrating the coordination of metabolism and oncogenic pathways could be key druggable targets for specific inhibition. Since PFK1 appears as the first tenor of this orchestra, its inhibition (and/or that of its main activator PFK2/PFKFB3) could be an efficacious strategy against NSCLC. Citrate is a potent physiologic inhibitor of both PFK1 and PFKFB3, and NSCLC cells seem to maintain a low citrate level to sustain aerobic glycolysis and the PFK1/PI3K/EGFR axis. Awaiting the development of specific non-toxic inhibitors of PFK1 and PFK2/PFKFB3, we propose to test strategies increasing citrate levels in NSCLC tumors to disrupt this interconnection. This could be attempted by evaluating inhibitors of the citrate-consuming enzyme ACLY and/or by direct administration of citrate at high doses. In preclinical models, this "citrate strategy" efficiently inhibits PFK1/PFK2, HIF-1α, and IGFR/PI3K/AKT axes. It also blocks tumor growth in RAS-driven lung cancer models, reversing dedifferentiation, promoting T lymphocytes tumor infiltration, and increasing sensitivity to cytotoxic drugs.

Surgical Resection for Pulmonary Carcinoid: Long-Term Results of Multicentric Study-The Importance of Pathological N Status, More Than We Thought.

BACKGROUND: Histological subdivision into typical (TC) and atypical (AC) is crucial for treatment and prognosis of lung carcinoids but can be also very challenging, even for experts. In this study, we aimed to strengthen or reduce the prognostic value of several pathological, clinical, or per-operative factors some of which are still controversial. METHODS: We retrospectively reviewed clinical records related to 195 patients affected by TC (159) or AC (36) surgically treated between 2000 and 2014, in three different centers. Survival and subtypes comparison analyses were performed to identify potential prognostic factors. RESULTS: TCs showed a lower rate of nodal involvement than ACs (N0 = 94.9%; N1 = 1.9%; N2 = 3.2% in typical and N0 = 63.8%; N1 = 16.6%; N2 = 19.4% in atypical carcinoids, respectively, p < 0.0001). Long-term oncological results of resected carcinoids were significantly better in TCs than ACs with higher 5- and 10-year overall survival rates (97.2 and 88.2% vs. 77.9 and 68.2%, respectively; p = 0.001) and disease-free survival rates (98.2 and 90.3% in typical and 80.8 and 70.7% atypical carcinoids, respectively; p = 0.001). Risk factors analysis revealed that AC subtype [HR 4.33 (95% CI 1.72-8.03), p = 0.002], pathological nodal involvement [HR 3.05 (95% CI 1.77-5.26), p < 0.0001], and higher SUVmax [HR 4.33 (95% CI 1.03-7.18), p = 0.002] were independently and pejoratively associated with overall survival. Factors associated with a higher risk of recurrence were AC subtype [HR 6.13 (95% CI 1.13-18.86), p = 0.002]; nodal involvement [HR 5.48 (95% CI 2.85-10.51), p < 0.0001]; higher Ki67 expression level [HR 1.09 (95% CI 1.01-1.20), p = 0.047]; and SUVmax [HR 1.83 (95% CI 1.04-3.23), p = 0.035]. CONCLUSION: Surgery for lung carcinoids allows satisfactory oncological results which mainly depend on carcinoid subtype dichotomy, pathological nodal status, and SUVmax.

Intratumoral distribution of EGFR mutations and copy number in metastatic lung cancer, what impact on the initial molecular diagnosis?

BACKGROUND: Activating epidermal growth factor receptor (EGFR) mutations characterize a subgroup of non-small-cell lung cancer that benefit from first line EGFR tyrosine kinase inhibitors (EGFR-TKI). However, the existence of polyclonal cell populations may hinder personalized-medicine strategies as patients' screening often depends upon a single tumor-biopsy sample. The purpose of this study is to clarify and to validate in clinical testing conditions the accuracy of EGFR genotyping using different tumor sites and various types of samples (transthoracic, surgical or endoscopic biopsies and cytology specimens). METHODS: We conducted a retrospective review of 357 consecutive patients addressed for EGFR mutation screening in accordance with the directive of the European Medicines Agency (stage IV NSCLC). Fifty-seven samples were EGFR mutated and 40 had adequate tumor specimens for analysis on multiple spatially separated sites. Ten wild type samples were also analyzed. A total of 153 and 39 tumor fragments, from mutated and non-mutated cases respectively, were generated to analyze tumor heterogeneity or primary-metastatic discordances. After histological review of all fragments, EGFR genotyping was assessed using the routine diagnostic tools: fragment analysis for insertions and deletions and allele specific TaqMan probes for point mutations. EGFR copy number (CN) was evaluated by qPCR using TaqMan probes. RESULTS: The identification of EGFR mutations was independent of localization within primary tumor, of specimen type and consistent between primary and metastases. At the opposite, for half of the samples, tumor loci showed different EGFR copy number that may affect mutation detection cut-off. CONCLUSIONS: This is the largest series reporting multiple EGFR testing in Caucasians. It validates the accuracy of EGFR mutation screening from single tumor-biopsy samples before first line EGFR-TKI. The unpredictable variability in EGFR CN and therefore in EGFR wild type/mutant allelic ratio justifies the implementation of sensitive methods to identify patients with EGFR mutated tumors.

Lung carcinoid tumors with Diffuse Idiopathic Pulmonary NeuroEndocrine Cell Hyperplasia (DIPNECH) exhibit pejorative pathological features.

INTRODUCTION: Diffuse Idiopathic Pulmonary NeuroEndocrine Cell Hyperplasia (DIPNECH) is a rare disease often associated with carcinoid tumors. We aimed at evaluating the impact of DIPNECH on characteristics and prognosis of patients who underwent radical treatment of pulmonary carcinoid tumors. MATERIAL AND METHODS: We reviewed all patients operated on for curative-intent resection of carcinoid tumor in our department from 2001 to 2020. Cases exhibiting both pathological and radiological features of DIPNECH, as assessed by respective thoracic expert physicians, were analyzed separately. RESULTS: 172 cases of resected carcinoid tumors were identified, including 25 (14.5 %) harboring pathological criteria of DIPNECH and radiologic features like mosaic attenuation (92.0 %), multiple nodules < 5 mm (76.0 %), and mucoid impactions (32 %). In DIPNECH patients, major pulmonary resections were usually performed (92.0 %) and resected tumors were mostly classified as pT1 (92 %). Mean Ki67 staining was 3.7 ± 5.2 %. The early postoperative period was mostly uneventful (96.0 %) and 5-year survival was 92.9 ± 6.9 %. Compared to non-DIPNECH cases, we found that patients were older (mean 65.6 ± 9.3 versus 54.1 ± 17.9, p = 0.002), more frequently female (84.0 % versus 56.5 %, p = 0.009), and exhibiting diabetes mellitus (45.8 % versus 18.5 %, p < 0.001) or hypertension (45.8 % versus 24.1 %, p = 0.039). The rate of atypical carcinoid tumors was significantly higher in DIPNECH patients (40.0 % versus 19.9 %, p = 0.027), as well as rate of mediastinal lymph-nodes involvement (pN2+) (36.0 % versus 4.1 %, p < 0.001). At multivariate analysis, only DIPNECH pattern and atypical histology were independent factors of pN2 invasion which was the only predictor of poorer prognosis on Log-Rank test. CONCLUSION: Carcinoid tumors with proven DIPNECH are associated with negative pathological features and may deserve a dedicated perioperative management.

Long-Term Imaging Follow-Up in DIPNECH: Multicenter Experience.

Diffuse pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare pre-invasive disease whose pathophysiology remains unclear. We aimed to assess long-term evolution in imaging of DIPNECH, in order to propose follow-up recommendations. Patients with histologically confirmed DIPNECH from four centers, evaluated between 2001 and 2020, were enrolled if they had at least two available chest computed tomography (CT) exams performed at least 24 months apart. CT exams were analyzed for the presence and the evolution of DIPNECH-related CT findings. Twenty-seven patients, mostly of female gender (n = 25/27; 93%) were included. Longitudinal follow-up over a median 63-month duration (IQR: 31-80 months) demonstrated an increase in the size of lung nodules in 19 patients (19/27, 70%) and the occurrence of metastatic spread in three patients (3/27, 11%). The metastatic spread was limited to mediastinal lymph nodes in one patient, whereas the other two patients had both lymph node and distant metastases. The mean time interval between baseline CT scan and metastatic spread was 70 months (14, 74 and 123 months). Therefore, long-term annual imaging follow-up of DIPNECH might be appropriate to encompass the heterogeneous longitudinal behavior of this disease.

PD-L1-expression patterns in large-cell neuroendocrine carcinoma of the lung: potential implications for use of immunotherapy in these patients: the GFPC 03-2017 "EPNEC" study.

BACKGROUND: Few data are available on programmed cell-death-protein-1-ligand-1 (PD-L1) expression on large-cell neuroendocrine carcinomas of the lung (LCNECs). We analyzed PD-L1 expression on tumor (TCs) and inflammatory cells (ICs) from LCNEC patients to assess relationships between this expression, clinical characteristics, and disease outcomes. METHODS: PD-L1 expression was determined by immunohistochemistry with monoclonal antibody 22C3 in consecutive LCNEC patients managed in 17 French centers between January 2014 and December 2016. RESULTS: After centralized review, only 68 out of 105 (64%) patients had confirmed LCNEC diagnoses. Median overall survival (OS) (95% CI) was 11 (7-16) months for all patients, 7 (5-10), 21 (10-not reached) and not reached months for metastatic, stage III and localized forms (p = 0.0001). Respectively, 11% and 75% of the tumor samples were TC+ and IC+, and 66% had a TC-/IC+ profile. Comparing IC+ versus IC- metastatic LCNEC, the former had significantly longer progression-free survival [9 (4-13) versus 4 (1-8) months; p = 0.03], with a trend towards better median OS [12 (7-18) versus 9.5 (4-14) months; p = 0.21]. Compared to patients with TC- tumors, those with TC+ LCNECs tended to have non-significantly shorter median OS [4 (1-6.2) versus 11 (8-18) months, respectively]. Median OS was significantly shorter for patients with TC+/IC- metastatic LCNECs than those with TC-IC+ lesions (2 versus 8 months, respectively; p = 0.04). CONCLUSION: TC-/IC+ was the most frequent PD-L1-expression profile for LCNECs, a pattern quite specific compared with non-small-cell lung cancer and small-cell lung cancer. IC PD-L1 expression seems to have a prognostic role.

The new histologic classification of lung primary adenocarcinoma subtypes is a reliable prognostic marker and identifies tumors with different mutation status: the experience of a French cohort.

BACKGROUND: Histologic classification of lung adenocarcinoma subtype has a prognostic value in most studies. However, lung adenocarcinoma characteristics differ across countries. Here, we aimed at validating the prognostic value of this classification in a large French series of lung adenocarcinoma. METHODS: We reviewed 407 consecutive lung adenocarcinomas operated on between 2001 and 2005 and reclassified them according to the International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification and subsequently graded them into low, intermediate, and high grade. We analyzed the relevance of this classification according to clinical, pathologic, and molecular analysis. RESULTS: Patients (median age, 61 years; 288 men) underwent lobectomy (n = 378) or pneumonectomy (n = 29). Patients' overall survival at 5 and 10 years was 53.2% and 32.6%, respectively. Union for International Cancer Control stage distribution was 189 stage I, 104 stage II, 107 stage III, and seven stage IV. Low-grade tumor was found in one patient, intermediate grade in 275 patients, and high grade in 131 patients. KRAS and EGFR mutations were detected in 34% and 9.6%, respectively. Histologic grade was significantly correlated with extent of resection (P = .01), thyroid transcriptional factor-1 expression (P = .00000001), vascular emboli (P = .03), and EGFR mutations (P = .01). Mucinous adenocarcinomas were associated with KRAS mutations (P = .003). At univariate analysis, age, extent of resection, histologic grade, pleural invasion, vascular emboli, pathologic T and N, and stage were predictive of survival. At multivariate analysis, age (P = .0001), histologic grade (P = .03), and stage (P = .000003) were independent prognostic factors. CONCLUSIONS: IASLC/ATS/ERS classification of lung adenocarcinomas predicts survival in French population. Histologic grade correlates with clinical, pathologic and molecular parameters suggesting different oncogenic pathways.

Surgical management of pulmonary large cell neuroendocrine carcinomas: a 10-year experience.

OBJECTIVES: Large cell neuroendocrine carcinoma (LCNEC) represents a relatively rare and poorly studied entity whose management is not clearly established. The aim of this study was to assess clinico-pathological characteristics, treatment modalities and outcomes of LCNEC. METHODS: A retrospective study of patients operated on for LCNEC between 2000 and 2010 was carried out. RESULTS: Sixty-three patients (49 men, median age 64 years) with pathologically confirmed LCNEC of the lung were operated on between 2000 and 2010. Neoadjuvant chemotherapy was administered in 16 cases. Standard lobectomy, sleeve lobectomy, bilobectomy and pneumonectomy were performed in 63.5%, 9.5%, 1.6% and 15.8% of cases. There were two cases of extended resection. Sublobar resections were performed in four patients. Postoperative mortality was 1.6%. Postoperative staging was IA, IB, IIA, IIB, IIIA, IIIB and IV in 15.9%, 19%, 20.6%, 4.8%, 34.9%, 4.8% and 0% of cases, respectively. Adjuvant treatments were administered in 70% of cases. Overall 5-, and 8- year survival rates were 49.2% (37-61.6%) and 42% (28.8-56.4%), respectively. Multivariate analysis, including age >64 years, cumulative tobacco consumption, size of tumour, pT and pN parameters showed that only age (P = 0.05, RR 2.1 [0.99-4.43]) and pT parameter (P = 0.0078, RR 2.93[1.33-6.46]) were independent predictors of survival. CONCLUSIONS: Surgery may achieve satisfactory results in terms of survival, in spite of the similarities of LCNEC with small cell lung cancer. Multimodality management seems necessary.