Hypoxia, angiogenesis, and lung cancer

Hypoxia promotes metastasis by relieving miR-598-3p-restricted glycolysis in gastric cancer

The activation of glycolysis, particularly in the context of reprogrammed energy metabolism, is increasingly recognized as a significant characteristic of cancer. However, the precise mechanisms by which glycolysis is promoted in metastatic gastric cancer cells under normal oxygen conditions remain poorly understood. MicroRNAs (miRNAs) play a crucial role in the development of malignant phenotypes in gastric cancer. Nevertheless, our understanding of the specific involvement of miRNAs in hypoxia-induced metabolic shifting and the subsequent metastatic processes is limited. Hypoxia-induced downregulation of miR-598-3p mechanistically leads to the upregulation of RMP and IGF1r, thereby promoting glycolysis. Either overexpression of miR-598-3p or R406 treatment effectively suppresses the metastasis of gastric cancer cells both in vitro and in vivo. Collectively, the depletion of miR-598-3p alters glucose metabolism from oxidative phosphorylation to glycolysis, thereby exacerbating the malignancy of gastric cancer cells. The present findings indicate a potential target for the development of therapeutics against gastric cancers with increased miR-598-3p expression.

Identification of hypoxia-related gene signatures based on multi-omics analysis in lung adenocarcinoma

Lung adenocarcinoma (LUAD) is the most common type of lung cancer and one of the malignancies with the highest incidence rate and mortality worldwide. Hypoxia is a typical feature of tumour microenvironment (TME), which affects the progression of LUAD from multiple molecular levels. However, the underlying molecular mechanisms behind LUAD hypoxia are not fully understood. In this study, we estimated the level of hypoxia by calculating a score based on 15 hypoxia genes. The hypoxia scores were relatively high in LUAD patients with poor prognosis and were bound up with tumour node metastasis (TNM) stage, tumour size, lymph node, age and gender. By comparison of high hypoxia score group and low hypoxia score group, 1820 differentially expressed genes were identified, among which up-regulated genes were mainly about cell division and proliferation while down-regulated genes were primarily involved in cilium-related biological processes. Besides, LUAD patients with high hypoxia scores had higher frequencies of gene mutations, among which TP53, TTN and MUC16 had the highest mutation rates. As for DNA methylation, 1015 differentially methylated probes-related genes were found and may play potential roles in tumour-related neurobiological processes and cell signal transduction. Finally, a prognostic model with 25 multi-omics features was constructed and showed good predictive performance. The area under curve (AUC) values of 1-, 3- and 5-year survival reached 0.863, 0.826 and 0.846, respectively. Above all, our findings are helpful in understanding the impact and molecular mechanisms of hypoxia in LUAD.

HER2 Alterations in Non-Small Cell Lung Cancer: Biologico-Clinical Consequences and Interest in Therapeutic Strategies

Lung cancer stands as the first cause of death by cancer in the world. Despite the improvement in patients' outcomes in the past decades through the development of personalized medicine approaches, a substantial portion of patients remains ineligible for targeted therapies due to the lack of a "druggable" molecular target. HER2, a receptor tyrosine kinase member of the EGFR/ErbB family, is known to show oncogenic properties. In this review, we focus on the different HER2 dysregulation mechanisms that have been observed in non-small cell lung cancer (NSCLC): gene mutation, gene amplification, protein overexpression and protein hyper-phosphorylation, the latter suggesting that HER2 dysregulation can occur independently of any molecular aberration. These HER2 alterations inevitably have consequences on tumor biology. Here, we discuss how they are not only involved in abnormal proliferation and survival of cancer cells but also potentially in increased angiogenic properties, mesenchymal features and tumor immune escape. Finally, we review the impact of these HER2 alterations in various therapeutic approaches. While standard chemotherapy and groundbreaking immunotherapy seem rather ineffective for HER2-altered NSCLCs, the development of HER2-targeted therapies such as tyrosine kinase inhibitors, anti-HER2 antibodies and especially antibody-drug conjugates could provide new hopes for patients.

Machine learning developed a programmed cell death signature for predicting prognosis and immunotherapy benefits in lung adenocarcinoma

BACKGROUND

Lung cancer is the leading cause of cancer-related deaths worldwide with poor prognosis. Programmed cell death (PCD) plays a crucial function in tumor progression and immunotherapy response in lung adenocarcinoma (LUAD).

METHODS

Integrative machine learning procedure including 10 methods was performed to develop a prognostic cell death signature (CDS) using TCGA, GSE30129, GSE31210, GSE37745, GSE42127, GSE50081, GSE68467, GSE68571, and GSE72094 dataset. The correlation between CDS and tumor immune microenvironment was evaluated using various methods and single cell analysis. qRT-PCR and CCK-8 assay were conducted to explore the biological functions of hub gene.

RESULTS

The prognostic CDS developed by Lasso + survivalSVM method was regarded as the optimal prognostic model. The CDS had a stable and powerful performance in predicting the clinical outcome of LUAD and served as an independent risk factor in TCGA and 8 GEO datasets. The C-index of CDS was higher than that of clinical stage and many developed signatures for LUAD. LUAD patients with low CDS score had a higher PD1&CTLA4 immunophenoscore, higher TMB score, lower TIDE score and lower tumor escape score, indicating a better immunotherapy benefit. Single cell analysis revealed a strong and frequent communication between epithelial cells and cancer-related fibroblasts by specific ligand-receptor pairs, including COL1A2-SDC4 and COL1A2-SDC1. Vitro experiment showed that SLC7A5 was upregulated in LUAD and knockdown of SLC7A5 obviously suppressed tumor cell proliferation.

CONCLUSION

Our study developed a novel CDS for LUAD. The CDS served as an indicator for predicting the prognosis and immunotherapy benefits of LAUD patients.

Exosome nanovesicles as potential biomarkers and immune checkpoint signaling modulators in lung cancer microenvironment: recent advances and emerging concepts

Lung cancer remains the leading cause of cancer-related deaths globally, and the survival rate remains low despite advances in diagnosis and treatment. The progression of lung cancer is a multifaceted and dynamic phenomenon that encompasses interplays among cancerous cells and their microenvironment, which incorporates immune cells. Exosomes, which are small membrane-bound vesicles, are released by numerous cell types in normal and stressful situations to allow communication between cells. Tumor-derived exosomes (TEXs) possess diverse neo-antigens and cargoes such as proteins, RNA, and DNA and have a unique molecular makeup reflecting tumor genetic complexity. TEXs contain both immunosuppressive and immunostimulatory factors and may play a role in immunomodulation by influencing innate and adaptive immune components. Moreover, they transmit signals that contribute to the progression of lung cancer by promoting metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and immunosuppression. This makes them a valuable resource for investigating the immune environment of tumors, which could pave the way for the development of non-invasive biomarkers that could aid in the prognosis, diagnosis, and immunotherapy of lung cancer. While immune checkpoint inhibitor (ICI) immunotherapy has shown promising results in treating initial-stage cancers, most patients eventually develop adaptive resistance over time. Emerging evidence demonstrates that TEXs could serve as a prognostic biomarker for immunotherapeutic response and have a significant impact on both systemic immune suppression and tumor advancement. Therefore, understanding TEXs and their role in lung cancer tumorigenesis and their response to immunotherapies is an exciting research area and needs further investigation. This review highlights the role of TEXs as key contributors to the advancement of lung cancer and their clinical significance in lung immune-oncology, including their possible use as biomarkers for monitoring disease progression and prognosis, as well as emerging shreds of evidence regarding the possibility of using exosomes as targets to improve lung cancer therapy.

Neutrophils correlate with hypoxia microenvironment and promote progression of non-small-cell lung cancer

Hypoxia, a strong and selective pressure, has been involved in invasion, metastasis, and angiogenesis of tumor cells. Our study performed the transcriptome profiles of 666 non-small-cell lung cancer (NSCLC) patients. Various bioinformatic approaches were combined to evaluate the immune cell infiltration in the high hypoxia risk patients. In addition, in vitro experiments were performed to assess the effects of tumor-associated neutrophils (TANs) on NSCLC cells proliferation, migration and invasion and to reveal the underlying mechanisms. We divided NSCLC into two groups (Cluster1/2) based on the expression profiles of hypoxia-associated genes. Compared with the Cluster1 subgroup, the Cluster2 had a worse prognosis. Significant enrichment analysis revealed that PI3K/AKT/mTOR signaling pathway and TANs were highly related to hypoxia microenvironment. Eleven hypoxia-related genes (FBP1, NDST2, ADM, LDHA, DDIT4, EXT1, BCAN, IGFBP1, PDGFB, AKAP12, and CDKN3) were scored by LASSO COX regression to yield risk scores, and we revealed a significant difference in overall survival (OS) between the low- and high-risk groups. Mechanistically, CXCL6 in hypoxic cancer cells promoted the migration of TANs in vitro, and in turn promote NSCLC cells proliferation, migration and invasion. In summary, this study revealed a 11‐hypoxia gene signature that predicted OS of NSCLC patients, and improved our understanding of the role of TANs in hypoxia microenvironment.

Comparison of Improvement in 2-Year Survival Rate of Patients with Stage II-III Non-Small Cell Lung Cancer Treated with Different Durations of Chinese Patent Medicine: A Retrospective Cohort Study

Background: Chinese patent medicine is widely used among patients with malignant tumors, and current studies have shown that long-term treatment with Chinese patent medicine is related to improved outcomes of patients. Huisheng Oral Liquid is a kind of Chinese patent medicine with the effects of curing dispersion-thirst and dissipating blood stasis. However, little is known about how it affects the survival rate of patients. Thus, patients with stage II-III NSCLC (non-small-cell lung cancer) were chosen to participate in a retrospective cohort study, which was conducted to preliminarily investigate the effects of using Chinese patent medicine and Huisheng Oral Liquid for different treatment durations on patients' 2-year survival rate and explore the prognostic factors affecting the 2-year survival rate of those patients. Purpose: This work compares the effect of different durations of treatment with Chinese patent medicine and Huisheng Oral Liquid on the 2-year survival rate of patients with stage II-III NSCLC and explores the prognostic factors of the patients' 2-year survival rate. Methods: This retrospective cohort study included patients with non-small cell lung cancer stage II-III according to the 2015 NCCN Guidelines: Non-Small Cell Lung Cancer. The Kaplan-Meier method was used to compare the 2-year survival rate of patients treated with different durations of Chinese medicine and Huisheng Oral Liquid. The relationship between different treatment durations and degree of improvement of 2-year survival rate was explored using the Cochran-Armitage trend test. The Cox proportional-hazards regression models were used to explore factors affecting the 2-year survival rate of patients. Results: A total of 614 patients with stage II-III NSCLC diagnosed from January 2015 to December 2018 were included in this study. Patients treated with Chinese patent medicine were divided into three groups by treatment durations: < 3 months, ≥ 3 months, and ≥6 months, and those treated with Huisheng Oral Liquid were divided into < 3 months and ≥3 and ≥6 months. The results showed that ① the 2-year survival rate of patients treated with Chinese patent medicine for ≥3 months and ≥6 months was higher than that of patients treated for <3 months and the difference was statistically significant (p < 0.05). Further analysis of Huisheng Oral Liquid treatment revealed that ② the 2-year survival rate of patients treated with Huisheng Oral Liquid for ≥3 months was higher than that of patients treated for <3 months (p < 0.05). Because the total number of patients treated with Huisheng Oral Liquid for ≥6 months and the number of patients with improved outcomes were too small, there was no statistically significant difference in the 2-year survival rate between the two groups (p > 0.05). The results of the Cochran-Armitage trend test showed that the 2-year survival rate tended to increase with the duration of Huisheng Oral Liquid treatment (p < 0.05). ③ The Cox proportional -hazards regression model revealed that among all 614 patients, surgery [HR = 0.48, 95% CI = (0.34, 0.68)], chemotherapy [HR = 0.46, 95% CI = (0.31,0.67)], and treatment with Huisheng Oral Liquid for ≥3 months were protective factors [HR = 0.48, 95%CI = (0.27,0.88)], whereas male gender [HR = 1.59, 95% CI = (1.01, 2.50)] and FIB ≥4 g/L [HR = 1.95, 95% CI = (1.37, 2.77)] were risk factors. Conclusion: Chinese patent medicine treatment for ≥3 months showed an improvement in the 2-year survival rate of patients with stage II-III NSCLC. Patients treated with Huisheng Oral liquid for ≥3 months also showed an improvement in the 2-year survival rate, and the 2-year survival rate tended to increase as the treatment duration increased. Finally, male and FIB ≥ 4 g/L were risk factors for prognosis.

Hypoxia in Lung Cancer Management: A Translational Approach

Simple Summary

Hypoxia is a common feature of lung cancers. Nonetheless, no guidelines have been established to integrate hypoxia-associated biomarkers in patient management. Here, we discuss the current knowledge and provide translational novel considerations regarding its clinical detection and targeting to improve the outcome of patients with non-small-cell lung carcinoma of all stages.

Abstract

Lung cancer represents the first cause of death by cancer worldwide and remains a challenging public health issue. Hypoxia, as a relevant biomarker, has raised high expectations for clinical practice. Here, we review clinical and pathological features related to hypoxic lung tumours. Secondly, we expound on the main current techniques to evaluate hypoxic status in NSCLC focusing on positive emission tomography. We present existing alternative experimental approaches such as the examination of circulating markers and highlight the interest in non-invasive markers. Finally, we evaluate the relevance of investigating hypoxia in lung cancer management as a companion biomarker at various lung cancer stages. Hypoxia could support the identification of patients with higher risks of NSCLC. Moreover, the presence of hypoxia in treated tumours could help clinicians predict a worse prognosis for patients with resected NSCLC and may help identify patients who would benefit potentially from adjuvant therapies. Globally, the large quantity of translational data incites experimental and clinical studies to implement the characterisation of hypoxia in clinical NSCLC management.

Alternatively Expressed Transcripts Analysis of Non-Small Cell Lung Cancer Cells under Different Hypoxic Microenvironment

Globally, non-small cell lung cancer (NSCLC) is the most fatal form of malignancy. Numerous studies have shown that people living at high altitudes are at a higher risk for cancer. Hypoxia is one of the most important features in high altitude area. Compared with normal cells, cancer cells are more adapted to hypoxia atmosphere. However, at high altitudes, hypoxic conditions are also accompanied by other altered environmental conditions. To identify the single influence of hypoxia, we performed second-generation sequencing to identify gene expression changes triggered by the different oxygen concentrations. We identified 782 genes in A549 cells and 1122 genes in H520 cells that showed altered expression by the combined analysis in 5% oxygen concentration group and 1% oxygen concentration group control group. We further analyzed these targets and found 113 genes altered in both cell lines. Interestingly, we found KxD1 was the only one in both top 10 lists. Further analysis revealed KxD1 to be significantly elevated in NSCLC patients and negatively correlated with prognosis in stage I and II NSCLC patients. Moreover, this correlation reversed in stage III patients. Additionally, compared with patients who only received clean margin operation or chemotherapy, patients who received radiotherapy also showed opposite result. Thus, KxD1 may be a promising target for the treatment of NSCLC in high-altitude areas.

Beyond Conventional: The New Horizon of Anti-Angiogenic microRNAs in Non-Small Cell Lung Cancer Therapy

GLOBOCAN 2018 identified lung cancer as the leading oncological pathology in terms of incidence and mortality rates. Angiogenesis is a key adaptive mechanism of numerous malignancies that promotes metastatic spread in view of the dependency of cancer cells on nutrients and oxygen, favoring invasion. Limitation of the angiogenic process could significantly hamper the disease advancement through starvation of the primary tumor and impairment of metastatic spread. This review explores the basic molecular mechanisms of non-small cell lung cancer (NSCLC) angiogenesis, and discusses the influences of the key proangiogenic factors-the vascular endothelial growth factor-A (VEGF-A), basic fibroblast growth factor (FGF2), several matrix metalloproteinases (MMPs-MMP-2, MMP-7, MMP-9) and hypoxia-and the therapeutic implications of microRNAs (miRNAs, miRs) throughout the entire process, while also providing critical reviews of a number of microRNAs, with a focus on miR-126, miR-182, miR-155, miR-21 and let-7b. Finally, current conventional NSCLC anti-angiogenics-bevacizumab, ramucirumab and nintedanib-are briefly summarized through the lens of evidence-based medicine.

Volumetric and texture analysis of pretherapeutic 18F-FDG PET can predict overall survival in medullary thyroid cancer patients treated with Vandetanib

PURPOSE

The metabolically most active lesion in 2-deoxy-2-(¹⁸F)fluoro-D-glucose (¹⁸F-FDG) PET/CT can predict progression-free survival (PFS) in patients with medullary thyroid carcinoma (MTC) starting treatment with the tyrosine kinase inhibitor (TKI) vandetanib. However, this metric failed in overall survival (OS) prediction. In the present proof of concept study, we aimed to explore the prognostic value of intratumoral textural features (TF) as well as volumetric parameters (total lesion glycolysis, TLG) derived by pre-therapeutic ¹⁸F-FDG PET.

METHODS

Eighteen patients with progressive MTC underwent baseline ¹⁸F-FDG PET/CT prior to and 3 months after vandetanib initiation. By manual segmentation of the tumor burden at baseline and follow-up PET, intratumoral TF and TLG were computed. The ability of TLG, imaging-based TF, and clinical parameters (including age, tumor marker doubling times, prior therapies and RET (rearranged during transfection) mutational status) for prediction of both PFS and OS were evaluated.

RESULTS

The TF Complexity and the volumetric parameter TLG obtained at baseline prior to TKI initiation successfully differentiated between low- and high-risk patients. Complexity allocated 10/18 patients to the high-risk group with an OS of 3.3 y (vs. low-risk group, OS = 5.3 y, 8/18, AUC = 0.78, P = 0.03). Baseline TLG designated 11/18 patients to the high-risk group (OS = 3.5 y vs. low-risk group, OS = 5 y, 7/18, AUC = 0.83, P = 0.005). The Hazard Ratio for cancer-related death was 6.1 for Complexity (TLG, 9.5). Among investigated clinical parameters, the age at initiation of TKI treatment reached significance for PFS prediction (P = 0.02, OS, n.s.).

CONCLUSIONS

The TF Complexity and the volumetric parameter TLG are both independent parameters for OS prediction.

Development of single nanometer-sized ultrafine oxygen bubbles to overcome the hypoxia-induced resistance to radiation therapy via the suppression of hypoxia-inducible factor‑1α

Radiation therapy can result in severe side-effects, including the development of radiation resistance. The aim of this study was to validate the use of oxygen nanobubble water to overcome resistance to radiation in cancer cell lines via the suppression of the hypoxia-inducible factor 1-α (HIF-1α) subunit. Oxygen nanobubble water was created using a newly developed method to produce nanobubbles in the single-nanometer range with the ΣPM-5 device. The size and concentration of the oxygen nanobubbles in the water was examined using a cryo-transmission electron microscope. The nanobubble size was ranged from 2 to 3 nm, and the concentration of the nanobubbles was calculated at 2×10¹⁸ particles/ml. Cell viability and HIF-1α levels were evaluated in EBC-1 lung cancer and MDA-MB-231 breast cancer cells treated with or without the nanobubble water and radiation under normoxic and hypoxic conditions in vitro. The cancer cells grown in oxygen nanobubble-containing media exhibited a clear suppression of hypoxia-induced HIF-1α expression compared to the cells grown in media made with distilled water. Under hypoxic conditions, the EBC-1 and MDA-MB231 cells displayed resistance to radiation compared to the cells cultured under normoxic cells. The use of oxygen nanobubble medium significantly suppressed the hypoxia-induced resistance to radiation compared to the use of normal medium at 2, 6, 10 and 14 Gy doses. Importantly, the use of nanobubble media did not affect the viability and radiation sensitivity of the cancer cell lines, or the non-cancerous cell line, BEAS-2B, under normoxic conditions. This newly created single-nanometer range oxygen nanobubble water, without any additives, may thus prove to be a promising agent which may be used to overcome the hypoxia-induced resistance of cancer cells to radiation via the suppression of HIF-1α.

Differential Roles of Angiogenesis in the Induction of Fibrogenesis and the Resolution of Fibrosis in Liver

Liver fibrosis is a wound healing process that includes inflammation, deposition of extracellular matrix molecules, and pathological neovascularization. Angiogenesis, which is defined by the formation of new blood vessels from pre-existing vessels, is a complex and dynamic process under both physiological and pathological conditions. Although whether angiogenesis can induce or occur in parallel with the progression of hepatic fibrosis has not yet been determined, intrahepatic sinusoidal formation and remodeling are key features of liver fibrosis. Some recent evidence has suggested that experimental inhibition of angiogenesis ameliorates the development of liver fibrosis, while other recent studies indicate that neutralization or genetic ablation of vascular endothelial growth factor (VEGF) in myeloid cells can delay tissue repair and fibrosis resolution in damaged liver. In this review, we briefly summarize the current knowledge about the differential roles of angiogenesis in the induction of fibrogenesis and the resolution of fibrosis in damaged livers. Possible strategies for the prevention and treatment of liver fibrosis are also discussed.

Erlotinib-cisplatin combination inhibits growth and angiogenesis through c-MYC and HIF-1α in EGFR-mutated lung cancer in vitro and in vivo

Combination treatment for non–small cell lung cancer (NSCLC) is becoming more popular due to the anticipation that it may be more effective than single drug treatment. In addition, there are efforts to genetically screen patients for specific mutations in light of attempting to administer specific anticancer agents that are most effective. In this study, we evaluate the anticancer and anti-angiogenic effects of low dose erlotinib-cisplatin combination in NSCLC in vitro and in vivo. In NSCLC cells harboring epidermal growth factor receptor (EGFR) mutations, combination erlotinib-cisplatin treatment led to synergistic cell death, but there was minimal efficacy in NSCLC cells with wild-type EGFR. In xenograft models, combination treatment also demonstrated greater inhibition of tumor growth compared to individual treatment. The anti-tumor effect observed was secondary to the targeting of angiogenesis, evidenced by decreased vascular endothelial growth factor (VEGF) levels and decreased levels of CD31 and microvessel density. Combination treatment targets angiogenesis through down-regulation of the c-MYC/hypoxia inducible factor 1-alpha (HIF-1α) pathway. In fact, cell lines with EGFR exon 19 deletions expressed high basal levels of c-MYC and HIF-1α and correlate with robust responses to combination treatment. These results suggest that low dose erlotinib-cisplatin combination exhibits its anti-tumor activity by targeting angiogenesis through the modulation of the c-MYC/HIF-1α/VEGF pathway in NSCLC with EGFR exon 19 deletions. These findings may have significant clinical implications in patients with tumors harboring EGFR exon 19 deletions as they may be particularly sensitive to this regimen.

IL-6 trans-signaling increases expression of airways disease genes in airway smooth muscle

Genetic data suggest that IL-6 trans-signaling may have a pathogenic role in the lung; however, the effects of IL-6 trans-signaling on lung effector cells have not been investigated. In this study, human airway smooth muscle (HASM) cells were treated with IL-6 (classical) or IL-6+sIL6R (trans-signaling) for 24 h and gene expression was measured by RNAseq. Intracellular signaling and transcription factor activation were assessed by Western blotting and luciferase assay, respectively. The functional effect of IL-6 trans-signaling was determined by proliferation assay. IL-6 trans-signaling had no effect on phosphoinositide-3 kinase and Erk MAP kinase pathways in HASM cells. Both classical and IL-6 trans-signaling in HASM involves activation of Stat3. However, the kinetics of Stat3 phosphorylation by IL-6 trans-signaling was different than classical IL-6 signaling. This was further reflected in the differential gene expression profile by IL-6 trans-signaling in HASM cells. Under IL-6 trans-signaling conditions 36 genes were upregulated, including PLA2G2A, IL13RA1, MUC1, and SOD2. Four genes, including CCL11, were downregulated at least twofold. The expression of 112 genes was divergent between IL-6 classical and trans-signaling, including the genes HILPDA, NNMT, DAB2, MUC1, WWC1, and VEGFA. Pathway analysis revealed that IL-6 trans-signaling induced expression of genes involved in regulation of airway remodeling, immune response, hypoxia, and glucose metabolism. Treatment of HASM cells with IL-6+sIL6R induced proliferation in a dose-dependent fashion, suggesting a role for IL-6 trans-signaling in asthma pathogenesis. These novel findings demonstrate differential effect of IL-6 trans-signaling on airway cells and identify IL-6 trans-signaling as a potential modifier of airway inflammation and remodeling.

Clinical implications of serum hypoxia inducible factor-1α and vascular endothelial growth factor in lung cancer

AIMS AND BACKGROUND

Hypoxia inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF) have been deemed as key in angiogenesis of lung cancer. The aim of this study was to investigate diagnostic and prognostic values of HIF-1α and VEGF in patients with lung cancer.

METHODS

From May 1, 2011, to April 20, 2014, blood samples and/or pleural effusions were collected from 100 patients with lung cancer, 18 patients with tuberculosis, 47 patients with community-acquired pneumonia, and 29 healthy controls. The pretreatment levels of HIF-1α and VEGF were measured by enzyme-linked immunoassays. Patients with lung cancer were followed up during the period of this study and survival times were recorded for analysis.

RESULTS

We detected that the levels of serum and pleural HIF-1α in lung cancer were significantly higher than those in the tuberculosis population, and that the VEGF expressions were not significantly different between malignancy and benign diseases. An area under the curve of pleural HIF-1α (0.877 ± 0.053) showed a high ability to differentiate lung cancer from benign diseases. The significant negative predictors of survival in the univariate analysis were performance status (gt;1), no anticancer therapy, low serum albumin, advanced stage, and serum high level of VEGF (gt;324.17 pg/mL), while in the multivariate Cox regression analysis, only the pretreatment serum level of VEGF, stage, and anticancer therapy were identified as independent prognostic factors.

CONCLUSIONS

The overexpression of HIF-1α especially in pleural effusion may be an angiogenic factor for distinguishing malignancy from tuberculosis, and the pretreatment level of serum VEGF may be an independent predictor of survival.

Update on implications and mechanisms of angiogenesis in liver fibrosis

Liver fibrosis occurs as a compensatory response to the process of tissue repair in a wide range of chronic liver injures. It is characterized by excessive deposition of extracellular matrix in liver tissues. As the pathogenesis progresses without effective management, it will lead to formation of liver fiber nodules and disruption of normal liver structure and function, finally culminating in cirrhosis and hepatocellular carcinoma. A new discovery shows that liver angiogenesis is strictly associated with, and may even favor fibrogenic progression of chronic liver diseases. Recent basic and clinical investigations also demonstrate that liver fibrogenesis is accompanied by pathological angiogenesis and sinusoidal remodeling, which critically determine the pathogenesis and prognosis of liver fibrosis. Inhibition of pathological angiogenesis is considered to be a new strategy for the treatment of liver fibrosis. This review summarizes current knowledge on the process of angiogenesis, the relationships between angiogenesis and liver fibrosis, and on the molecular mechanisms of liver angiogenesis. On the other hand, it also presents the different strategies that have been used in experimental models to counteract excessive angiogenesis and the role of angiogenesis in the prevention and treatment of liver fibrosis.

PET with 62Cu-ATSM and 62Cu-PTSM is a useful imaging tool for hypoxia and perfusion in pulmonary lesions

OBJECTIVE

Hypoxia is a characteristic of many tumors and portends a worse prognosis in lung, cervical, prostate, and rectal cancers. Unlike the others, lung cancers present a unique challenge in measuring hypoxia, with invasive biopsies and higher rates of complications. Noninvasive imaging studies detecting hypoxia using isotopes of copper-diacetyl-bis(N4-methylthiosemicarbazone) ((62)Cu-ATSM) have predicted prognosis and treatment outcomes in some small feasibility trials. These images, however, may not identify all areas of hypoxia. Hence, we hypothesize that the addition of another PET imaging agent, copper-pyruvaldehyde-bis(N4-methylthiosemicarbazone) ((62)Cu-PTSM), which can detect areas of perfusion, can augment the information obtained in (62)Cu-ATSM PET scans.

SUBJECTS AND METHODS

To characterize tumors on the basis of both perfusion and hypoxia, 10 patients were studied using both (62)Cu-ATSM and (62)Cu-PTSM PET scans. In addition, proteomic arrays looking at specific proangiogenic, survival, and proinflammatory targets were assessed.

RESULTS

Six of 10 patients had evaluable PET scans. Our initial experience of characterizing lung tumor hypoxia using (62)Cu-ATSM and (62)Cu-PTSM PET scans showed that visualization of areas with hypoxia normalized for perfusion is feasible. All studied tumors exhibited some hypoxia. Despite the small sample size, a positive relationship was noted between epidermal growth factor levels and (62)Cu-ATSM-detected hypoxia.

CONCLUSION

This initial series of (62)Cu-ATSM and (62)Cu-PTSM PET scans shows that evaluating lung masses by visualizing hypoxia and perfusion is a feasible and novel technique to provide more information. Further investigation is warranted to assess the potential role of (62)Cu-ATSM and (62)Cu-PTSM PET techniques combined with proteomics as alternatives to invasive biopsy techniques in clinical care.

Treatment with EGCG in NSCLC leads to decreasing interstitial fluid pressure and hypoxia to improve chemotherapy efficacy through rebalance of Ang-1 and Ang-2

AIM

Microvasculature and microenvironment play important roles in proliferation, invasion, metastasis and prognosis in non-small cell lung cancer (NSCLC), which might be altered by many anti-angiogenic drugs. Epigallocatechin-3-gallate (EGCG), a natural anti-angiogenesis agent refined from green tea, was defined to have multiple effects on angiogenesis factors, such as endothelial growth factor (VEGF), platelet-derived growth factor (PDGF) and angiopoietins (ANGs). Hypothesizing that EGCG might regulate microvasculature and microenvironment in NSCLC, the effects of EGCG on microvessel density (MVD), expression of Ang-1 and Ang-2, interstitial fluid pressure (IFP), tumor hypoxia, and chemotherapy sensitivity were examined.

METHODS AND RESULTS

EGCG treatment of A549 cells in mice bearing xenografts in vivo led to a significant decrease of MVD detected by CD31, and of Ang-2 expression detected by quantum dots double-label immunofluorescence assessment, while Ang-1 decreased with no significance. Decreased IFP was measured by the Wink-in-needle method, while hypoxia was assessed by polarographic electrode and pimonidazole (PIMO) immunohistochemistry. Assuming that these changes would increase response to chemotherapy, tumor growth studies were p[erformed in nude mice with xenografts, which were then treated with EGCG and the chemotherapeutic agent cisplatin. EGCG therapy combined with cisplatin led to synergistic inhibition of tumor growth, compared with administration of each treatment separately (P < 0.001). According to linear regression analysis, IFP was positively correlated with PIMO staining (R(2) = 0.618, P = 0.002), Ang-2 was correlated with MVD (R(2) = 0.423, P = 0.022), IFP (R(2) = 0.663, P = 0.01) and PIMO staining (R(2) = 0.694, P = 0.01).

CONCLUSION

IFP and delivery of oxygen might be improved by rebalance of Ang-1/Ang-2 under the treatment of EGCG in NSCLC, which also acts as a sensitizer of chemotherapy. These studies established a new mechanism for using EGCG as an adjuvant chemotherapy agent through modifying microvasculature and microenvironment.

Oxidative stress and epigenetic instability in human hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is a major cause of cancer death, and its development is influenced by the status of inflammation and oxidative stress in the liver. Although oxidative stress might induce genetic changes and play a role in HCC development, many epigenetic alterations have also been reported in this type of tumor, suggesting the importance of epigenetic instability in hepatocarcinogenesis. Epigenetic instability results in 2 types of DNA alterations: hypermethylation of the promoter of tumor suppressor genes (TSGs), and hypomethylation of nonpromoter CpG, such as repetitive elements and satellite DNA. The former causes transcriptional inactivation of TSGs, while the latter reportedly induces chromosomal instability and an abnormal activation of oncogenes as well as mobile genetic elements. Oxidative stress could induce epigenetic instability and inactivate TSGs through the recruitment of the polycomb repressive complex to the promoter sequence carrying DNA damage induced by oxidation. Inflammatory cytokines from immune cells also reportedly induce expression of several histone and DNA modulators. On the other hand, DNA oxidation could lead to activation of DNA repair pathways and affect the binding of methyl cytosine-binding protein to DNA, which could cause DNA hypomethylation. The decrease of the level of methyl group donors also contributes to the alteration in the methylation status. These mechanisms should act in concert and induce epigenetic instability, leading to HCC.

Evolving strategies: future treatment of glioblastoma

Despite recent advances, there remains an unmet need for more effective treatments for newly diagnosed and recurrent glioblastoma (GBM). While currently available alkylator-based and antiangiogenic agents provide some efficacy, novel antiangiogenic and antiglioma treatments that provide enhanced efficacy with improvements in overall survival, the potential to overcome drug resistance and decreased treatment-related toxicity are still needed. Although VEGF-directed angiogenesis is critical during GBM pathogenesis, alternative proangiogenic and glioma-promoting pathways also play a key role in tumor progression. This article reviews the limitations of current GBM treatment, the importance of angiogenic signaling pathways in GBM pathogenesis and the preliminary results of novel antiangiogenic-targeted treatments being evaluated in GBM. Therapies that inhibit multiple glioma signaling pathways, including angiogenesis, have the possibility for further improving outcome in GBM and may represent the best option for increasing overall survival.

Cryoablation Combined with Molecular Target Therapy Improves the Curative Effect in Patients with Advanced Non-Small Cell Lung Cancer

This study investigated the curative effect of cryoablation combined with molecular target therapy for advanced non-small cell lung cancer (NSCLC). Thirty-six female patients with NSCLC and epidermal growth factor receptor gene mutations were randomly divided into two groups: 18 patients received the molecular target therapy gefitinib (group I), an epidermal growth factor receptor-tyrosine kinase inhibitor; and 18 patients were treated with cryoablation prior to the administration of gefitinib (group II).

Treatment with gefitinib was continued for 6 months. Compared with group I, the rates of partial regression, stabilization of disease and progression of disease were improved in group II at the end of the 6 months of gefitinib treatment. Moreover, the 1-year survival rate in group II was significantly higher than that in group I. This suggests that cryoablation therapy combined with gefitinib could improve the effects of treatment and the prognosis of patients with advanced NSCLC.

Targeting oxidative stress in cancer

IMPORTANCE OF THE FIELD

Reactive oxygen species (ROS) occur as natural by-products of oxygen metabolism and have important cellular functions. Normally, the cell is able to maintain an adequate balance between the formation and removal of ROS either via anti-oxidants or through the use specific enzymatic pathways. However, if this balance is disturbed, oxidative stress may occur in the cell, a situation linked to the pathogenesis of many diseases, including cancer.

AREAS COVERED IN THIS REVIEW

HDACs are important regulators of many oxidative stress pathways including those involved with both sensing and coordinating the cellular response to oxidative stress. In particular aberrant regulation of these pathways by histone deacetylases may play critical roles in cancer progression.

WHAT THE READER WILL GAIN

In this review we discuss the notion that targeting HDACs may be a useful therapeutic avenue in the treatment of oxidative stress in cancer, using chronic obstructive pulmonary disease (COPD), NSCLC and hepatocellular carcinoma (HCC) as examples to illustrate this possibility.

TAKE HOME MESSAGE

Epigenetic mechanisms may be an important new therapeutic avenue for targeting oxidative stress in cancer.

Inhibition of tumor growth and angiogenesis by a lysophosphatidic acid antagonist in an engineered three-dimensional lung cancer xenograft model

BACKGROUND

: We developed an engineered three-dimensional (3D) tumor xenograft model of nonsmall cell lung cancer (NSCLC) in nude mice, and we used this model to evaluate a dual-activity inhibitor of lysophosphatidic acid (LPA) biosynthesis and receptor activation.

METHODS

: First, BrP-LPA, a pan-antagonist for 4 LPA receptors and inhibitor of the lyosphospholipase D activity of autotaxin, was examined for inhibition of cell migration and cell invasion by human NSCLC A549 cells. Second, A549 cells were encapsulated in 3D in 3 semisynthetic extracellular matrices (ECMs) based on chemically modified glycosaminoglycans, and injected subcutaneously in nude mice. Tumor volume and vascularity were determined as a function of semisynthetic ECMs composition. Third, engineered NSCLC xenografts were formed from A549 cells in either Extracel-HP or Matrigel, and mice were treated with 4 intraperitoneal injections of 3 mg/kg of BrP-LPA.

RESULTS

: First, BrP-LPA inhibited cell migration and invasiveness of A549 cells in vitro. Second, tumor growth and microvessel formation for 3D encapsulated A549 cells in vivo in nude mice increased in the following order: buffer only < Extracel < Extracel-HP < Extracel-HP containing growth factorss plus laminin. Third, tumor volumes increased rapidly in both Matrigel and Extracel-HP encapsulated A549 cells, and tumor growth was markedly inhibited by BrP-LPA treatment. Finally, tumor vascularization was dramatically reduced in the A549 tumors treated with BrP-LPA.

CONCLUSIONS

: Engineered A549 lung tumors can be created by 3D encapsulation in an ECM substitute with user controlled composition. The engineered tumors regress and lose vascularity in response to a dual activity inhibitor of the LPA signaling pathway. Cancer 2010. (c) 2010 American Cancer Society.

Pentastatin-1, a collagen IV derived 20-mer peptide, suppresses tumor growth in a small cell lung cancer xenograft model

Background

Angiogenesis is the formation of neovasculature from a pre-existing vascular network. Progression of solid tumors including lung cancer is angiogenesis-dependent. We previously introduced a bioinformatics-based methodology to identify endogenous anti-angiogenic peptide sequences, and validated these predictions in vitro in human umbilical vein endothelial cell (HUVEC) proliferation and migration assays.

Methods

One family of peptides with high activity is derived from the α-fibrils of type IV collagen. Based on the results from the in vitro screening, we have evaluated the ability of a 20 amino acid peptide derived from the α5 fibril of type IV collagen, pentastatin-1, to suppress vessel growth in an angioreactor-based directed in vivo angiogenesis assay (DIVAA). In addition, pentastatin-1 suppressed tumor growth with intraperitoneal peptide administration in a small cell lung cancer (SCLC) xenograft model in nude mice using the NCI-H82 human cancer cell line.

Results

Pentastatin-1 decreased the invasion of vessels into angioreactors in vivo in a dose dependent manner. The peptide also decreased the rate of tumor growth and microvascular density in vivo in a small cell lung cancer xenograft model.

Conclusions

The peptide treatment significantly decreased the invasion of microvessels in angioreactors and the rate of tumor growth in the xenograft model, indicating potential treatment for angiogenesis-dependent disease, and for translational development as a therapeutic agent for lung cancer.

Proteomics-based identification of two novel direct targets of hypoxia-inducible factor-1 and their potential roles in migration/invasion of cancer cells

Hypoxia-inducible factor-1 (HIF-1), consisting of oxygen-sensitive HIF-1alpha and constitutively expressed HIF-1beta subunits, is a master transcriptional activator for cellular response to hypoxia. To explore direct HIF-1 targets, here we used differential gel electrophoresis (DIGE) to compare the HIF-1-regulated proteins between leukemic U937T-cell line with and without conditional induction of HIF-1alpha protein by tetracycline-off system. Among the upregulated proteins identified, mRNA levels of annexin A1, macrophage-capping protein (CapG), S100 calcium-binding protein A4 (S100A4), S100A11, acyl-CoA-binding protein and calcyclin-binding protein also increased. The expressions of the annexin A1, CapG and S100A4 genes were significantly induced by hypoxia in five adherent cell lines tested besides U937 cells, while their expressions were blocked by the short hairpin RNA specifically against HIF-1alpha. Further luciferase reporter assay and chromatin immunoprecipitation showed that HIF-1alpha directly bound to three hypoxia-responsive elements located at intron 1 of S100A4 gene and hypoxia-responsive element at -350 to -346 of CapG gene, which are essential for HIF-1-induced expression. Additionally, the role of S100A4 expression in migration and invasion of cancer cells were also confirmed. These findings would provide new sights for understanding the molecular mechanisms underlying HIF-1 action.

Evaluating dual activity LPA receptor pan-antagonist/autotaxin inhibitors as anti-cancer agents in vivo using engineered human tumors

Using an in situ cross-linkable hydrogel that mimics the extracellular matrix (ECM), cancer cells were encapsulated and injected in vivo following a "tumor engineering" strategy for orthotopic xenografts. Specifically, we created several three-dimensional (3D) human tumor xenografts and evaluated the tumor response to BrP-LPA, a novel dual function LPA antagonist/ATX inhibitor (LPAa/ATXi). First, we describe the model system and the optimization of semi-synthetic ECM (sECM) compositions and injection parameters for engineered xenografts. Second, we summarize a study to compare angiogenesis inhibition in vivo, comparing BrP-LPA to the kinase inhibitor sunitinib maleate (Sutent). Third, we compare treatment of engineered breast tumors with LPAa/ATXi alone with treatment with Taxol. Fourth, using a re-optimized sECM for non-small cell lung cancer cells, we created reproducibly sized subcutaneous lung tumors and evaluated their response to treatment with LPAa/ATXi. Fifth, we summarize the data on the use of LPAa/ATXi to treat a model for colon cancer metastasis to the liver. Taken together, these improved, more realistic xenografts show considerable utility for evaluating the potential of novel anti-metastatic, anti-proliferative, and anti-angiogenic compounds that modify signal transduction through the LPA signaling pathway.

Oxidative stress induced lung cancer and COPD: opportunities for epigenetic therapy

Reactive oxygen species (ROS) form as a natural by-product of the normal metabolism of oxygen and play important roles within the cell. Under normal circumstances the cell is able to maintain an adequate homeostasis between the formation of ROS and its removal through particular enzymatic pathways or via antioxidants. If however, this balance is disturbed a situation called oxidative stress occurs. Critically, oxidative stress plays important roles in the pathogenesis of many diseases, including cancer. Epigenetics is a process where gene expression is regulated by heritable mechanisms that do not cause any direct changes to the DNA sequence itself, and disruption of epigenetic mechanisms has important implications in disease. Evidence is emerging that histone deacetylases (HDACs) play decisive roles in regulating important cellular oxidative stress pathways including those involved with sensing oxidative stress and those involved with regulating the cellular response to oxidative stress. In particular aberrant regulation of these pathways by HDACs may play critical roles in cancer progression. In this review we discuss the current evidence linking epigenetics and oxidative stress and cancer, using chronic obstructive pulmonary disease and non-small cell lung cancer to illustrate the importance of epigenetics on these pathways within these disease settings.