Lymphangiogenic Markers and Their Impact on Nodal Metastasis and Survival in Non-Small Cell Lung Cancer--A Structured Review with Meta-Analysis

Participation of hypoxia-inducible factor-1α and lymphangiogenesis in metastatic and non-metastatic lower lip squamous cell carcinoma

This study evaluated the lymphatic density and HIF-1α immunoexpression in lower lip squamous cell carcinoma (LLSCC) and their correlation with clinicopathological (nodal metastasis, clinical stage, histological grade, recurrence and disease outcome) and survival parameters in 20 metastatic and 20 non-metastatic LLSCCs. Lymphatic density was established by counting microvessels (D2-40⁺) at the tumor core (intratumoral lymphatic density, ILD) and at the invasive front (peritumoral lymphatic density, PLD) and percentages of immunopositive cells for HIF-1α were established. No statistically significant differences in lymphatic densities in relation to clinicopathological parameters were observed (P > 0.05). All cases exhibited nuclear and cytoplasmic HIF-1α immunoexpression, with relatively high percentages of positivity, but this expression was not statistically different in relation to clinicopathological variables (P > 0.05). Positive correlations were observed between ILD and PLD (P = 0.002), and between nuclear HIF-1α immunoexpression at the tumor core and ILD (P = 0.001). The results suggest ILD and PLD are not directly related to the development of lymph node metastasis in LLSCC. The striking expression of HIF-1α suggests the involvement of this protein in the etiopathogenesis of LLSCCs, possibly stimulating lymphangiogenesis at the tumor core. However, this protein does not seem to exert a determining influence on the biological aggressiveness of these tumors.

Lymphatics-associated genes are downregulated at transcription level in non-small cell lung cancer

The present study aimed to verify a possibility of ongoing lymphangiogenesis in non-small cell lung cancer (NSCLC) via examination of mRNA levels of a number of lymphangiogenesis-associated genes in tumors. It was hypothesized that transcriptional activation of these genes would occur in tumors that stimulate new lymphatic vessel formation. The study was performed on 140 pairs of fresh-frozen surgical specimens of cancer and unaffected lung tissues derived from NSCLC stage I-IIIA patients. mRNA levels were evaluated with the reverse transcription-quantitative polymerase chain reaction method and expressed as fold change differences between the tumor and normal tissues. Possible associations between expression and patient clinicopathological characteristics and survival were analyzed. In the NSCLC tissue samples, vascular endothelial growth factor (VEGF) C, VEGFD, VEGFR3, VEGFR2, VEGFR1, lymphatic vessel endothelial hyaluronan receptor 1, integrin subunit α 9, FOX2, neuropilin 2, fibroblast growth factor 2 genes were significantly downregulated (P<0.001 for all) compared with matched normal lung tissues, whereas mRNA levels for VEGFA, spleen associated tyrosine kinase, podoplanin, and prospero homeobox 1 genes were similar in both tissues. Neither lymph node status, nor disease pathological stage influenced expression, whereas more profound suppression of gene activities appeared to occur in squamous cell carcinomas compared with adenocarcinomas. The VEGFR1 mRNA expression level was significantly connected with patient survival in the univariate analysis, and was an independent prognostic factor for overall survival in the multivariate Cox's proportional hazards model (HR 2.103; 95% confidence interval: 1.005-4.401; P=0.049). The results support a hypothesis of absence of new lymphatic vessel formation inside growing NSCLC tumor mass, however do not exclude a possibility of lymphangiogenesis in narrow marginal tumor parts.

A meta-analysis of the lymphatic microvessel density and survival in gastric cancer with 1809 cases

Lymph node metastasis commonly occurs in gastric cancer. Previous studies have demonstrated that the overexpression of lymphatic microvessel density (LVD) is correlated with various malignancies. To evaluate the potential role of LVD in various malignancies, we conducted a systematic review and meta-analysis to thoroughly investigate the association of LVD expression with tumor progression and survival in gastric cancer. We performed a comprehensive search of common databases and selected studies demonstrating the relationship between LVD expression and gastric cancer prognosis. Hazard ratios (HR) were used to determine the value of LVD for predicting gastric cancer metastasis and prognosis. The data were extracted from the included studies and pooled with the appropriate effects model using STATA 12.0. The results showed that high LVD expression obviously impacted the prognosis of gastric cancer, based on an overall survival (OS) HR of 2.58 (95% CI: 1.91–3.48, P < 0.001) and a disease-free survival (DFS) HR of 2.51 (95% CI: 1.35–4.68, P = 0.004) in the univariate analysis. In addition, the results of the multivariate analysis indicated a remarkable relationship between high LVD expression and gastric neoplasm prognosis. The pooled OS HR was 4.12 (95% CI: 3.45–4.91, P < 0.001). The current meta-analysis shows that high LVD is closely related to tumor metastasis and poor prognosis in gastric malignancy. LVD could be a key factor in tumor lymphatic metastasis. Moreover, LVD is likely a potential index and an effective biomarker for the prediction of patient prognosis.

Epithelial-to-Mesenchymal Transition and MicroRNAs in Lung Cancer

Despite major advances, non-small cell lung cancer (NSCLC) remains the major cause of cancer-related death in developed countries. Metastasis and drug resistance are the main factors contributing to relapse and death. Epithelial-to-mesenchymal transition (EMT) is a complex molecular and cellular process involved in tissue remodelling that was extensively studied as an actor of tumour progression, metastasis and drug resistance in many cancer types and in lung cancers. Here we described with an emphasis on NSCLC how the changes in signalling pathways, transcription factors expression or microRNAs that occur in cancer promote EMT. Understanding the biology of EMT will help to define reversing process and treatment strategies. We will see that this complex mechanism is related to inflammation, cell mobility and stem cell features and that it is a dynamic process. The existence of intermediate phenotypes and tumour heterogeneity may be debated in the literature concerning EMT markers, EMT signatures and clinical consequences in NSCLC. However, given the role of EMT in metastasis and in drug resistance the development of EMT inhibitors is an interesting approach to counteract tumour progression and drug resistance. This review describes EMT involvement in cancer with an emphasis on NSCLC and microRNA regulation.

Prognostic value of number of negative lymph node in patients with stage II and IIIa non-small cell lung cancer

Background

The definitive validation evidence of the implications of lymph node metastases regarding the survival of Non-Small Cell Lung Cancer (NSCLC) patients is lacking. We aimed to evaluate the prognostic impact of several lymph node metastases-associated risk factors including Number of Negative Lymph Node (NLN) and risk-stratify NSCLC patients into subsets with different prognosis.

Method

A total of 482 patients with N1 and N2 NSCLC were included in this study. The prognostic importance of a set of risk factors was examined by univariate and multivariate analysis. The cut-off points and 5 years survival rates were calculated to test the best grouping system to stratify the patients with difference outcome.

Results

Our analysis indicated that both Ratio of the Metastatic Lymph nodes (RML) and Number of Negative Lymph Node (NLN) were associated with overall survival (OS) and disease free survival (DFS). RML percentage 20% and 55%, and NLN counts 10 and 30 were proved as the optimal cut-off points to predict OS by classifying patients into 3 groups, respectively. RML and NLN actually are more powerful in predicting survival outcome for male patients compared to female patients. Stratified survival analyses using combined factors indicated that the 5-year survival rate (5-YSR) is high in RML I + NLN I/III subgroup (5-YSR = 57.1% and 43.3%) and low in RML III + NLN II/III subgroup (5-YSR = 0.0 % each).

Conclusions

NLN is a strong prognostic factor for OS and DFS of stage II/IIIa NSCLC patients, and provides a useful classification scheme for NSCLC patients when combined with RML.

Structural alterations in tumor-draining lymph nodes before papillary thyroid carcinoma metastasis

BACKGROUND

The purpose of this study was to define and characterize the thyroid tumor-draining lymph nodes in genetically engineered mice harboring thyroid-specific expression of oncogenic Braf^V600E with and without Pten insufficiency.

METHODS

After intratumoral injection of methylene blue, the lymphatic drainage of the thyroid gland was visualized in real time. The thyroid gland/tumor was resected en bloc with the respiratory system for histological analysis.

RESULTS

Although mice harboring Braf^V600E mutations were smaller in body size compared with their wild-type (WT) littermates, the size of their thyroid glands and deep cervical lymph nodes were significantly larger. Additionally, the tumor-draining lymph nodes showed increased and enlarged lymphatic sinuses that were distributed throughout the cortex and medulla. Tumor-reactive lymphadenopathy and histiocytosis, but no frank metastases, were observed in all mice harboring Braf^V600E mutations.

CONCLUSIONS

The tumor-draining lymph nodes undergo significant structural alterations in immunocompetent mice, and this may represent a primer for papillary thyroid carcinoma (PTC) metastasis.

Jin Fu Kang Oral Liquid Inhibits Lymphatic Endothelial Cells Formation and Migration

Lung cancer is the leading cause of cancer-related deaths worldwide. Jin Fu Kang (JFK), an oral liquid prescription of Chinese herbal drugs, has been clinically available for the treatment of non-small cell lung cancer (NSCLC). Lymphangiogenesis is a primary event in the process of cancer development and metastasis, and the formation and migration of lymphatic endothelial cells (LECs) play a key role in the lymphangiogenesis. To assess the activity of stromal cell-derived factor-1 (SDF-1) and the coeffect of SDF-1 and vascular endothelial growth factor-C (VEGF-C) on the formation and migration of LECs and clarify the inhibitory effects of JFK on the LECs, the LECs were differentiated from CD34⁺/VEGFR-3⁺ endothelial progenitor cells (EPCs), and JFK-containing serums were prepared from rats. SDF-1 and VEGF-C both induced the differentiation of CD34⁺/VEGFR-3⁺ EPCs towards LECs and enhanced the LECs migration. Couse of SDF-1 and VEGF-C displayed an additive effect on the LECs formation but not on their migration. JFK inhibited the formation and migration of LECs, and the inhibitory effects were most probably via regulation of the SDF-1/CXCR4 and VEGF-C/VEGFR-3 axes. The current finding suggested that JFK might inhibit NSCLC through antilymphangiogenesis and also provided a potential to discover antilymphangiogenesis agents from natural resources.

Identifying candidate agents for lung adenocarcinoma by walking the human interactome

Despite recent advances in therapeutic strategies for lung cancer, mortality is still increasing. Therefore, there is an urgent need to identify effective novel drugs. In the present study, we implement drug repositioning for lung adenocarcinoma (LUAD) by a bioinformatics method followed by experimental validation. We first identified differentially expressed genes between LUAD tissues and nontumor tissues from RNA sequencing data obtained from The Cancer Genome Atlas database. Then, candidate small molecular drugs were ranked according to the effect of their targets on differentially expressed genes of LUAD by a random walk with restart algorithm in protein–protein interaction networks. Our method identified some potentially novel agents for LUAD besides those that had been previously reported (eg, hesperidin). Finally, we experimentally verified that atracurium, one of the potential agents, could induce A549 cells death in non-small-cell lung cancer-derived A549 cells by an MTT assay, acridine orange and ethidium bromide staining, and electron microscopy. Furthermore, Western blot assays demonstrated that atracurium upregulated the proapoptotic Bad and Bax proteins, downregulated the antiapoptotic p-Bad and Bcl-2 proteins, and enhanced caspase-3 activity. It could also reduce the expression of p53 and p21^Cip1/Waf1 in A549 cells. In brief, the candidate agents identified by our approach may provide greater insights into improving the therapeutic status of LUAD.