Activation of angiogenesis differs strongly between pulmonary carcinoids and neuroendocrine carinomas and is crucial for carcinoid tumourgenesis

Antitumor Activity of Axitinib in Lung Carcinoids: A Preclinical Study

Lung carcinoids (LCs) comprise well-differentiated neuroendocrine tumors classified as typical (TCs) and atypical (ACs) carcinoids. Unfortunately, curative therapies remain elusive for metastatic LCs, which account for 25-30% of cases. This study evaluated the antitumor activity of axitinib (AXI), a second-generation tyrosine kinase inhibitor selectively targeting vascular endothelial growth factor receptors (VEGFR-1, VEGFR-2, VEGFR-3) in human lung TC (NCI-H727, UMC-11, NCI-H835) and AC (NCI-H720) cell lines. In vitro and in vivo (zebrafish) assays were performed following AXI treatment to gather several read-outs about cell viability, cell cycle, the secretion of proangiogenic factors, apoptosis, tumor-induced angiogenesis and migration. AXI demonstrated relevant antitumor activity in human LC cells, with pronounced effects observed in UMC-11 and NCI-H720, characterized by cell cycle perturbation and apoptosis induction. AXI significantly hindered tumor induced-angiogenesis in Tg(fli1a:EGFP)y1 zebrafish embryos implanted with all LC cell lines and also reduced the invasiveness of NCI-H720 cells, as well as the secretion of several proangiogenic factors. In conclusion, our study provides initial evidence supporting the potential anti-tumor activity of AXI in LC, offering a promising basis for future investigations in mammalian animal models and, eventually, progressing to clinical trials.

Adjuvant chemotherapy, extent of resection, and immunoistochemical neuroendocrine markers as prognostic factors of early-stage large-cell neuroendocrine carcinoma

Background

We investigated whether adjuvant chemotherapy, extent of resection, and immunoistochemical neuroendocrine markers affected survival of patients with the early stage of large‐cell neuroendocrine cancer.

Methods

This was a retrospective multicenter study including consecutive patients undergoing resection of node negative large‐cell neuroendocrine carcinoma. Five‐year survival and disease‐free survival rate were evaluated by the Kaplan–Meier method and the log‐rank test in relation to adjuvant chemotherapy, extent of resection, and immunoistochemical neuroendocrine markers (synaptophysin, chromogranin A, and neuron‐specific enolase).

Results

Our study population included 117 patients; 47 (40%) of these received adjuvant chemotherapy. Patients treated with adjuvant chemotherapy had better survival (74% vs. 45%, p = 0.002) and disease‐free survival (79% vs. 40%, p = 0.001) in all cases except patients with tumor <20 mm (79.5% vs. 57.4%, p = 0.43). Lobectomy compared to sublobar resection was associated with better survival (67% vs. 0.1%, p < 0.0001) and disease‐free survival (65% vs. 0.1%, p < 0.0001) also in patients with tumor <20 mm (79% vs. 28%, p = 0.001). Patients with triple‐positive neuroendocrine markers had better survival (79% vs. 35%, p = 0.0001) and disease‐free survival (69% vs. 42%, p = 0.0008). Regression analysis showed that tumor size <20 mm, lobectomy, adjuvant chemotherapy, and triple‐positive immunistochemical neuroendocrine markers were significant favorable prognostic factors for survival outcomes.

Conclusions

Lobectomy seems to be the management of choice in patients with large‐cell neuroendocrine cancer <20 mm while adjuvant chemotherapy should be administered only in patients with tumor >20 mm.

Successful Treatment of Combined Large Cell Neuroendocrine Carcinoma Harboring an EGFR Mutation with EGFR-TKIs plus Bevacizumab: A Case Report

Large cell neuroendocrine carcinoma (LCNEC) of the lung with epidermal growth factor receptor (EGFR) mutation is rare, and few cases have been treated with EGFR tyrosine kinase inhibitors (TKIs). We report the treatment of combined LCNEC with adenocarcinoma harboring an EGFR mutation with EGFR-TKIs and bevacizumab. Our patient was a 70-year-old asymptomatic woman who underwent surgical resection of the lung for combined LCNEC with adenocarcinoma harboring an activating EGFR mutation 11 months previously. Magnetic resonance imaging (MRI) and positron emission tomography revealed metastatic lesions in the brain and lung. The patient was diagnosed with recurrence of combined LCNEC with adenocarcinoma. The brain lesion was irradiated, followed by administration of afatinib. Eight months after irradiation, brain MRI revealed ringed enhancement and perilesional edema after radiotherapy without new metastatic lesions. We switched treatment to erlotinib and bevacizumab, resulting in maintenance of stable disease for 10 months. Overall, the disease was controlled for 18 months with EGFR-TKIs and bevacizumab. Combination treatment with EGFR-TKIs and bevacizumab could be a treatment option for LCNEC of the lung harboring EGFR mutations, especially with brain metastasis.

Digital Immune-Related Gene Expression Signatures In High-Grade Serous Ovarian Carcinoma: Developing Prediction Models For Platinum Response

Purpose

Response to platinum-based therapy is a major prognostic factor in high-grade serous ovarian cancer (HGSOC). While the exact mechanisms of platinum-resistance remain unclear, evidence is accumulating for a connection between the organism’s immune-response and response to platinum. However, predictive tools are missing. This study was performed to examine the putative role of the genetic tumor immune-microenvironment in mediating differential chemotherapy response in HGSOC patients.

Patients and methods

Expression profiling of 770 immune-related genes was performed in tumor tissues from 23 HGSOC cases. Tumors were screened for prognostic and predictive biomarkers using the NanoString nCounter platform for digital gene expression analysis with the appurtenant PanCancer Immune Profiling panel. As validation cohort, gene expression data (RNA Seq) of 303 patients with epithelial ovarian carcinoma (EOC) were retrieved from the The Cancer Genome Atlas (TCGA) database. Different scoring-systems were computed for prediction of risk-of-resistance to cisplatin, disease-free survival (DFS) and overall survival (OS).

Results

Validated on the TCGA-dataset, the developed scores identified 11 significantly differentially expressed genes (p <0.01**) associated with platinum response. HSD11B1 was highly significantly associated with lower risk of recurrence and 7 targets were found highly significantly influencing OS time (p <0.01**).

Conclusion

Our results suggest that response to platinum-based therapy and DFS in ovarian HGSOC is associated with distinct gene-expression patterns related to the tumor immune-system. We generated predictive scoring systems which proved valid when applied to a set of 303 EOC patients.

Expression profiling and microRNA regulation of the LKB1 pathway in young and aged lung adenocarcinoma patients

Lung cancer in young patients appears to have distinct clinicopathological features. The present study focused on the role of the serine/threonine kinase liver kinase B1 (LKB1), a known tumor suppressor gene, and its miRNA regulation in lung adenocarcinoma, particularly in young versus elderly patients. A total of 88 patients with lung adenocarcinoma were retrospectively analysed. A simultaneous quantification was performed of the expression of LKB1 mRNA and 15 microRNAs (miRNA/miRs; miRs −93, −96, −34a, −34c, −214, −33a, −30b, −145, −182, −30c, −183, −29b, −29c, −153 and −138) involved in the LKB1 pathway, as well as of 5 identified target mRNAs [cyclin D1 (CCND1), catenin β-1 (CTNNB1), lysyl oxidase (LOX), yes-associated protein 1 (YAP1) and survivin], using NanoString technology. KRAS mutations were investigated by pyrosequencing analysis. Patients ≤50 years were defined as a younger group, while patients >50 years old as an older group (n=44/group). No difference between the two groups was identified in terms of survival times analysed using the Kaplan-Meier method or KRAS mutations. Subsequently, the LKB1 signalling pathway was focused on, as a target for therapy in lung adenocarcinoma, and assessed with regards to clinicopathological features; we found that LOX levels in adenocarcinoma patients were significantly associated with histological subtype (P=0.03), stage (P<0.0001) and prognosis (P=0.02 for disease-free interval and P=0.005 for overall survival), but not with age. Furthermore, the miRNA target prediction model indicated that miR-93 and miR-30b appeared to have functional binding sites and downregulate the gene expression of LKB1 and LOX, respectively. In conclusion, young patients appeared have similar survival rates to elderly patients. The assessment of LKB1, its downstream genes and its regulation by miRNAs may have an impact on future research on lung adenocarcinoma in young and elderly patients. Further investigations will be necessary to elucidate the potential of this pathway as a novel target for therapy.

New insights into hypoxia-related mechanisms involved in different microvascular patterns of bronchopulmonary carcinoids and poorly differentiated neuroendocrine carcinomas. Role of ribonuclease T2 (RNASET2) and HIF-1α

Ribonuclease T2 (RNASET2) is a pleiotropic and polyfunctional protein, which exerts several different activities in neoplastic cells since the early steps of tumor development. Besides having an antitumorigenic activity, RNASET2 inhibits both bFGF-induced and VEGF-induced angiogenesis and has a role as a stress-response, alarmin-like, protein. In this study, we investigated RNASET2 expression in well-differentiated and poorly differentiated neuroendocrine neoplasms of the lung (Lu-NENs), which are known to show clear-cut differences in morphology, biology and clinical behavior. In addition, we explored possible relationships between RNASET2 expression and a series of immunohistochemical markers related to hypoxic stress, apoptosis, proliferation and angiogenesis. Our results showed a significantly higher expression of RNASET2, HIF-1α, and its target CA IX in poorly differentiated than in well-differentiated Lu-NENs, the former also showing higher proliferation and apoptotic rates, as well as a lower microvessel density (MVD) than the latter. Moreover, we were able to demonstrate in vitro an overexpression of RNASET2 in consequence of the activation of HIF-1α. In conclusion, we suggest that in poorly differentiated Lu-NENs, RNASET2 expression may be induced by HIF-1α, behaving as an alarmin-like molecule. In this aggressive group of cancers, which have highly deregulated proliferation pathways, RNASET2 fails to exert the growth-inhibiting effects described in other types of neoplasms. Its increased expression, however, may contribute to the typical phenotypic alterations seen in poorly differentiated Lu-NENs, such as the high apoptotic rate and the extensive necrosis, and may also enhance the low MVD observed in these neoplasms.

Folic-acid metabolism and DNA-repair phenotypes differ between neuroendocrine lung tumors and associate with aggressive subtypes, therapy resistance and outcome

Purpose

25% of all lung cancer cases are neuroendocrine (NELC) including typical (TC) and atypical carcinoid (AC), large-cell neuroendocrine (LCNEC) and small cell lung cancer (SCLC). Prognostic and predictive biomarkers are lacking.

Experimental Design

Sixty patients were used for nCounter mRNA expression analysis of the folic-acid metabolism (ATIC, DHFR, FOLR1, FPGS, GART, GGT1, SLC19A1, TYMS) and DNA-repair (ERCC1, MLH1, MSH2, MSH6, XRCC1). Phenotypic classification classified tumors (either below or above the median expression level) with respect to the folic acid metabolism or DNA repair.

Results

Expression of FOLR1, FPGS, MLH1 and TYMS (each p<0.0001) differed significantly between all four tumor types. FOLR1 and FPGS associated with tumor differentiation (both p<0.0001), spread to regional lymph nodes (FOLR1 p=0.0001 and FPGS p=0.0038), OS and PFS (FOLR1 p<0.0050 for both and FPGS p<0.0004 for OS).

Phenotypic sorting revealed the Ft-phenotype to be the most prominent expression profile in carcinoids, whereas SCLC presented nearly univocal with the fT and LCNEC with fT or ft. These results were significant for tumor subtype (p<0.0001).

Conclusions

The assessed biomarkers and phenotypes allow for risk stratification (OS, PFS), diagnostic classification and enhance the biological understanding of the different subtypes of neuroendocrine tumors revealing potential new therapy options and clarifying known resistance mechanisms.

miRNA regulation is important for DNA damage repair and recognition in malignant pleural mesothelioma

Platin-containing regimes are currently considered as state-of-the-art therapies in malignant pleural mesotheliomas (MPM) but show dissatisfying response rates ranging from 6 to 16% only. Still, the reasons for the rather poor efficacy remain largely unknown. A clear stratification of patients based on new biomarkers seems to be a promising approach to enhance clinical management, which would be a long-needed improvement for MPM patients but does not seem likely soon unless new biomarkers can be validated. Twenty-four formalin-fixed, paraffin-embedded (FFPE) tumour specimens were subjected to a miRNA expression screening of 800 important miRNAs using digital quantification via the nCounter technique (NanoString). We defined a small subset of miRNAs regulating the key enzymes involved in the repair of platin-associated DNA damage. Particularly, the TP53 pathway network for DNA damage recognition as well as genes related to the term "BRCAness" are the main miRNA targets within this context. The TP53 pathway network for DNA damage recognition as well as genes related to the term "BRCAness" are the main players for risk stratification in patients suffering from this severe disease. Taking the specific molecular profile of the tumour into account can help to enhance the clinical management prospectively and to smooth the way to better response prediction.

microRNAs are differentially regulated between MDM2-positive and negative malignant pleural mesothelioma

Background

Malignant pleural mesothelioma (MPM) is a highly aggressive tumour first-line treated with a combination of cisplatin and pemetrexed. MDM2 and P14/ARF (CDKN2A) are upstream regulators of TP53 and may contribute to its inactivation. In the present study, we now aimed to define the impact of miRNA expression on this mechanism.

Material and Methods

24 formalin-fixed paraffin-embedded (FFPE) tumour specimens were used for miRNA expression analysis of the 800 most important miRNAs using the nCounter technique (NanoString). Significantly deregulated miRNAs were identified before a KEGG-pathway analysis was performed.

Results

17 miRNAs regulating TP53, 18 miRNAs regulating MDM2, and 11 miRNAs directly regulating CDKN2A are significantly downregulated in MDM2-expressing mesotheliomas. TP53 is downregulated in MDM2-negative tumours through miRNAs with a miSVR prediction score of 11.67, RB1 with a prediction score of 8.02, MDM2 with a prediction score of 4.50 and CDKN2A with a prediction score of 1.27.

Conclusion

MDM2 expression seems to impact miRNA expression levels in MPM. Especially, miRNAs involved in TP53-signaling are strongly decreased in MDM2-positive mesotheliomas. A better understanding of its tumour biology may open the chance for new therapeutic approaches and thereby augment patients' outcome.

ACTB, CDKN1B, GAPDH, GRB2, RHOA and SDCBP Were Identified as Reference Genes in Neuroendocrine Lung Cancer via the nCounter Technology

Background

Neuroendocrine lung cancer (NELC) represents 25% of all lung cancer cases and large patient collectives exist as formalin-fixed, paraffin-embedded (FFPE) tissue only. FFPE is controversially discussed as source for molecular biological analyses and reference genes for NELC are poorly establishes.

Material and methods

Forty-three representative FFPE-specimens were used for mRNA expression analysis using the digital nCounter technology (NanoString). Based on recent literature, a total of 91 mRNA targets were investigated as potential tumor markers or reference genes. The geNorm, NormFinder algorithms and coefficient of correlation were used to identify the most stable reference genes. Statistical analysis was performed by using the R programming environment (version 3.1.1)

Results

RNA integrity (RIN) ranged from 1.8 to 2.6 and concentrations from 34 to 2,109 ng/μl. However, the nCounter technology gave evaluable results for all samples tested. ACTB, CDKN1B, GAPDH, GRB2, RHOA and SDCBP were identified as constantly expressed genes with high stability (M-)values according to geNorm, NormFinder and coefficients of correlation.

Conclusion

FFPE-derived mRNA is suitable for molecular biological investigations via the nCounter technology, although it is highly degraded. ACTB, CDKN1B, GAPDH, GRB2, RHOA and SDCBP are potent reference genes in neuroendocrine tumors of the lung.

Screening of Pleural Mesotheliomas for DNA-damage Repair Players by Digital Gene Expression Analysis Can Enhance Clinical Management of Patients Receiving Platin-Based Chemotherapy

Background: Malignant pleural mesothelioma (MPM) is a rare, predominantly asbestos-related and biologically highly aggressive tumour leading to a dismal prognosis. Multimodality therapy consisting of platinum-based chemotherapy is the treatment of choice. The reasons for the rather poor efficacy of platinum compounds remain largely unknown.

Material and Methods: For this exploratory mRNA study, 24 FFPE tumour specimens were screened by digital gene expression analysis. Based on data from preliminary experiments and recent literature, a total of 366 mRNAs were investigated using a Custom CodeSet from NanoString. All statistical analyses were calculated with the R i386 statistical programming environment.

Results: CDC25A and PARP1 gene expression were correlated with lymph node spread, BRCA1 and TP73 expression levels with higher IMIG stage. NTHL1 and XRCC3 expression was associated with TNM stage. CHECK1 as well as XRCC2 expression levels were correlated with tumour progression in the overall cohort of patients. CDKN2A and MLH1 gene expression influenced overall survival in this collective. In the adjuvant treated cohort only, CDKN2A, CHEK1 as well as ERCC1 were significantly associated with overall survival. Furthermore, TP73 expression was associated with progression in this subgroup.

Conclusion: DNA-damage response plays a crucial role in response to platin-based chemotherapeutic regimes. In particular, CHEK1, XRCC2 and TP73 are strongly associated with tumour progression. ERCC1, MLH1, CDKN2A and most promising CHEK1 are prognostic markers for OS in MPM. TP73, CDKN2A, CHEK1 and ERCC1 seem to be also predictive markers in adjuvant treated MPMs. After a prospective validation, these markers may improve clinical and pathological practice, finally leading to a patients' benefit by an enhanced clinical management.

Prognostic markers and response to vandetanib therapy in sporadic medullary thyroid cancer patients

OBJECTIVE

Medullary thyroid carcinoma (MTC) occurs sporadically in 75% of patients. Metastatic disease is associated with significantly poorer survival. The aim of this study was to identify prognostic markers for progressive MTC and oncogenic factors associated with response to vandetanib therapy.

DESIGN AND METHODS

Clinical courses of 32 patients with sporadic MTC (n=10 pN0cM0, n=8 pN1cM0, n=14 pN1cM1) were compared with genetic profiles of the patients' primary tumour tissue. Analysis for RET proto-oncogene mutations was performed by Sanger sequencing and next-generation sequencing (NGS). The mRNA expression (mRNA count) of 33 targets was measured by nCounter NanoString analysis.

RESULTS

Somatic RET mutations occurred in 21/32 patients. The RET918 mutation was found in 8/14 pN1cM1 patients. BRAF (P=0.019), FGFR2 (P=0.007), FGFR3 (P=0.044) and VEGFC (P=0.042) mRNA expression was significantly lower in pN1cM0/pN1cM1 compared with pN0cM0 patients, whereas PDGFRA (P=0.026) mRNA expression was significantly higher in pN1cM0/pN1cM1 when compared with pN0cM0 patients. Among the 10/32 vandetanib-treated patients, 5 showed partial response (PR), all harbouring the RET918 mutation. mRNA expression of FLT1 (P=0.039), FLT4 (P=0.025) and VEGFB (P=0.042) was significantly higher in therapy responders.

CONCLUSIONS

In this study, we identified molecular markers in primary tumour tissue of sporadic MTC associated with the development of metastasis (both lymph node and organ metastasis) as well as response to vandetanib therapy.

Identification of deregulation of apoptosis and cell cycle in neuroendocrine tumors of the lung via NanoString nCounter expression analysis

Background

Neuroendocrine tumors of the lung comprise typical (TC) and atypical carcinoids (AC), large-cell neuroendocrine cancer (LCNEC) and small-cell lung cancer (SCLC). Cell cycle and apoptosis are key pathways of multicellular homeostasis and deregulation of these pathways is associated with cancerogenesis.

Materials and Methods

Sixty representative FFPE-specimens (16 TC, 13 AC, 16 LCNEC and 15 SCLC) were used for mRNA expression analysis using the NanoString technique. Eight genes related to apoptosis and ten genes regulating key points of cell cycle were investigated.

Results

ASCL1, BCL2, CASP8, CCNE1, CDK1, CDK2, CDKN1A and CDKN2A showed lower expression in carcinoids compared to carcinomas. In contrast, CCNE1 and CDK6 showed elevated expression in carcinoids compared to carcinomas. The calculated BCL2/BAX ratio showed increasing values from TC to SCLC.

Between SCLC and LCNEC CDK2, CDKN1B, CDKN2A and PNN expression was significantly different with higher expression in SCLC.

Conclusion

Carcinoids have increased CDK4/6 and CCND1 expression controlling RB1 phosphorylation via this signaling cascade. CDK2 and CCNE1 were increased in carcinomas showing that these use the opposite way to control RB1. BAX and BCL2 are antagonists in regulating apoptosis. BCL2 expression increased over BAX expression with increasing malignancy of the tumor from TC to SCLC.

Pulmonary Large-Cell Neuroendocrine Carcinoma: From Epidemiology to Therapy

Lung neuroendocrine tumors are a heterogeneous subtype of pulmonary cancers representing approximately 20% of all lung cancers, including small-cell lung cancer (SCLC) and large-cell neuroendocrine carcinoma (LCNEC). The frequency appears to be approximately 3% for LCNEC. Diagnosis of LCNEC requires attention to neuroendocrine features by light microscopy and confirmation by immunohistochemical staining for neuroendocrine markers. Both SCLC and pulmonary LCNEC are high-grade and poor-prognosis tumors, with higher incidence in males and smokers and peripheral localization. LCNEC is very rare, and the precise diagnosis on small specimens is very difficult, so we have still too few data to define a standard of treatment for pulmonary LCNECs. Data of literature, most based on retrospective analysis, indicated a poor 5-year overall survival, with a high incidence of recurrence after surgery, even in stage I disease. Primary surgery should be the first option in all operable patients because there is no validate therapeutic approach for LCNEC due to lack of clinical trials in this setting. Neoadjuvant platinum-based regimens remain only an option for potentially resectable tumors. In advanced stages, SCLC-like chemotherapy seems the best option of treatment, with a good response rate but a poor overall survival (from 8 to 16 months in different case series). New agents are under clinical investigation to improve LCNEC patients' outcome. We reviewed all data on treatment options feasible for pulmonary LCNEC, both for localized and extensive disease.

Relationship between expression and methylation of obesity-related genes in children

Epigenetic control of gene expression in children remains poorly understood, but new technologies can help elucidate the relationship between expression and DNA methylation. Here, we utilized the nCounter Analysis System to characterise the expression of 60 genes in 69 9-year-old children from a cohort with a high prevalence of obesity. nCounter expression levels ranged broadly (from 3 to over 10000 messenger RNA counts) and were divided into four categories: high (>2000 counts), moderate (200-1000 counts), low (100-200 counts) and marginal (<100 counts). For a subset of five genes (ADIPOR1, PPARG1, GSTM1, PON1 and ACACA) from different expression level categories, we validated nCounter data using reverse transcription-polymerase chain reaction (RT-PCR), and expanded RT-PCR analysis of ADIPOR1 to include 180 children. Expression data from the two methodologies were correlated for all five genes included in the validation experiment, with estimates ranging from r s = 0.26 (P = 0.02) to r s = 0.88 (P < 5×10(-6)). ADIPOR1 and PPARG1 nCounter expression levels were negatively correlated (r = -0.60, P < 5×10(-5)), and this relationship was stronger in overweight children (r = -0.73, P < 5×10(-5)) than in normal weight children (r = -0.42, P = 0.016). Using methylation data from the Infinium HumanMethylation450 BeadChip (n = 180), we found eight CpG sites in ADIPOR1 and PPARG where methylation level was associated with expression by RT-PCR (P < 0.05). Hypomethylation of PPARG gene body site cg10499651 was associated with increased expression as measured by both RT-PCR and nCounter (P < 0.05). We found no statistically significant relationships between either expression or methylation of ADIPOR1 and PPARG and body mass index or waist circumference. In addition to demonstrating the validity of expression data derived from nCounter, our results illustrate the use of new technologies in assessing epigenetic effects on expression in children.