Angiogenesis In Lung Adenocarcinoma Research Articles

FHL2 expression by cancer-associated fibroblasts promotes metastasis and angiogenesis in lung adenocarcinoma.

Cancer-associated fibroblasts (CAFs) contribute to the progression of lung cancer. Four and a half LIM domain protein-2 (FHL2) is a component of focal adhesion structures. We analyzed the function of FHL2 expressed by CAFs in lung adenocarcinoma. Expression of FHL2 in fibroblast subtypes was investigated using database of single-cell RNA-sequencing of lung cancer tissue. The role of FHL2 in the proliferation and migration of CAFs was assessed. The effects of FHL2 knockout on the migration and invasion of human lung adenocarcinoma cells and tube formation of endothelial cells induced by CAF-conditioned medium (CM) were evaluated. The effect of FHL2 knockout in CAFs on metastasis was determined using a murine orthotopic lung cancer model. The prognostic significance of stromal FHL2 was assessed by immunohistochemistry in human adenocarcinoma specimens. FHL2 is highly expressed in myofibroblasts in cancer tissue. TGF-β1 upregulated FHL2 expression in CAFs and FHL2 knockdown attenuated CAF proliferation. FHL2 knockout reduced CAF induced migration of A110L and H23 human lung adenocarcinoma cell lines, and the induction of tube formation of endothelial cells. FHL2 knockout reduced CAF-induced metastasis of lung adenocarcinomas in an orthotopic model in vivo. The concentration of Osteopontin (OPN) in CM from CAF was downregulated by FHL2 knockout. siRNA silencing and antibody blocking of OPN reduced the pro-migratory effect of CM from CAF on lung cancer cells. In resected lung adenocarcinoma specimens, positive stromal FHL2 expression was significantly associated with higher microvascular density and worse prognosis. In conclusion, FHL2 expression by CAFs enhances the progression of lung adenocarcinoma by promoting angiogenesis and metastasis.

Single-cell and Bulk RNA-Seq reveal angiogenic heterogeneity and microenvironmental features to evaluate prognosis and therapeutic response in lung adenocarcinoma.

Angiogenesis stands as a pivotal hallmark in lung adenocarcinoma (LUAD), intricately shaping the tumor microenvironment (TME) and influencing LUAD progression. It emerges as a promising therapeutic target for LUAD, affecting patients' prognosis. However, its role in TME, LUAD prognosis, and its clinical applicability remain shrouded in mystery. We employed integrated single-cell and bulk transcriptome sequencing to unravel the heterogeneity of angiogenesis within LUAD cells. Through "consensus clustering", we delineated distinct angiogenic clusters and deciphered their TME features. "Monocle2" was used to unravel divergent trajectories within malignant cell subpopulations of LUAD. Additionally, regulon submodules and specific cellular communication patterns of cells in different angiogenic states were analyzed by "pyscenic" and "Cellchat" algorithms. The "univariate Cox" and "LASSO" algorithms were applied to build angiogenic prognostic models. Immunohistochemistry (IHC) on clinical samples validated the role of model factors in LUAD angiogenesis. We utilized CTRP 2.0 and PRISM databases for pinpointing sensitive drugs against lung adenocarcinoma. Two clusters for the activation of angiogenesis were identified, with Cluster 1 showing a poor prognosis and a pro-cancerous TME. Three differentiated states of malignant epithelial LUAD cells were identified, which had different degrees of angiogenic activation, were regulated by three different regulon submodules, and had completely different crosstalk from other cells in TME. The experiments validate that SLC2A1 promotes angiogenesis in LUAD. ARS (Angiogenesis related score) had a high prognostic value; low ARSs showed immunotherapy benefits, whereas high ARSs were sensitive to 15 chemotherapeutic agents. The assessment of angiogenic clusters helps to determine the prognostic and TME characteristics of LUAD. Angiogenic prognostic models can be used to assess the prognosis, immunotherapeutic response, and chemotherapeutic drug sensitivity of LUAD.

Identification of ATAD3A as a key regulator in non-small cell lung cancer by promoting STAT3-induced cell proliferation and tumor angiogenesis.

Malignant proliferation and abundant angiogenesis are major causes of lung adenocarcinoma (LUAD) with high morbidity and mortality. Therefore, the exploration of the key regulatory mechanisms of malignant proliferation and angiogenesis in LUAD provides an opportunity for the development of targeted precision therapy. In this study, we found that the high expression of ATPase family AAA domain-containing protein 3A (ATAD3A) in LUADwas positively associated with the poor survival of patients, while its high expression was positively associated with the angiogenesis of LUAD. Further knockdown of ATAD3A in LUAD significantly inhibited cell proliferation and suppressed expression of vascular endothelial growth factor A, FGF-2, ANG-1, and TGF-β. The opposite effect was observed with ATAD3A overexpression. Furthermore, ATAD3A knockdown significantly inhibited tumor growth and angiogenesis in an in vivo subcutaneous xenograft tumor model. Mechanistic studies suggest that ATAD3A may promote signal transducer and activator of transcription 3 activation, a key signal regulating lung cancer cell proliferation and transcriptional secretion of proangiogenic factors. Therefore, targeted inhibition of ATAD3A may be an effective strategy for LUAD therapy, and ATAD3A may be a potential biomarker for predicting malignant progression.

PAR2 promotes tumor-associated angiogenesis in lung adenocarcinoma through activating EGFR pathway

BackgroundMetastasis of advanced lung adenocarcinoma (LUAD) is a key cause of cancer-related death, and angiogenesis is the main feature of tumor growth and metastasis. MethodsThe expression level of F2R like trypsin receptor 1(F2RL1) which encodes protease-activated receptor 2 (PAR2) protein in LUAD tissues was analyzed by bioinformatics. The effects of F2RL1 overexpression/silencing on cell proliferation and sphere-forming were analyzed by Cell Counting Kit-8 and colony formation assays, stem cell sphere-forming assay, and angiogenesis assay, respectively. The F2RL1 mRNA expression level and the PAR2 protein expression level, vascular endothelial growth factor A (VEGFA), and epidermal growth factor receptor (EGFR) in lung cancer cell lines were evaluated by real-time quantitative polymerase chain reaction and western blot. The level of VEGFA secreted by lung cancer cells was analyzed by Enzyme-linked immunosorbent assay (ELISA). The effect of F2RL1-mediated EGFR signaling on angiogenesis was further explored by EGFR inhibitor AG1478. ResultsF2RL1 was substantially up-regulated in LUAD tissues and cells, and overexpression of F2RL1 could promote proliferation and stem cell sphere-forming of lung cancer cell lines, as well as formation of blood vessels and branch points of human umbilical vein endothelial cells (HUVECs). Meanwhile, overexpression of F2RL1 significantly upregulated VEGFA expression and promoted EGFR phosphorylation. EGFR inhibitor AG1478 treatment significantly down-regulated pEGFR, and AG1478 treatment reversed the promoting effect of cancer cell cultured medium (oe-F2RL1) on HUVEC angiogenesis. SignificanceIn summary, this study revealed the molecular mechanism of PAR2 promoting LUAD angiogenesis by activating EGFR signaling pathway, which further improves our understanding of LUAD angiogenesis, and provides a potential therapeutic strategy for LUAD treatment.

Examination of Combined Treatment of Ginsenoside Rg3 and 5-Fluorouracil in Lung Adenocarcinoma Cells.

Chemotherapy is a commonly used strategy for advanced lung cancer patients. However, its clinical application is restrained due to its toxicity and drug resistance. Ginsenoside Rg3 (Rg3) has a strong anticancer influence on colon cancer, breast cancer, lung cancer, and other malignant tumors. However, it is still unclear whether Rg3 can cooperate with 5-FU to inhibit the tumor growth and angiogenesis of lung adenocarcinoma (LUAD). This study examined the combined treatment of Rg3 and 5-FU in LUAD. It was revealed that the combined treatment could notably enhance the suppression on proliferative, invasive, and migratory abilities and angiogenesis in LUAD cells A549 and SPC-A-1. On the other hand, we also discovered that Rg3 or 5-FU could suppress the activity of the NF-κB signaling pathway and downregulate VEGFA expression in LUAD cells. Collectively, this study suggested that Rg3 combined chemotherapy may perform a more powerful drug efficiency in LUAD cells.

Role of von Willebrand factor in the angiogenesis of lung adenocarcinoma.

Lung adenocarcinoma (LUAD) has a high morbidity and mortality rate worldwide, and its growth and metastasis require angiogenesis. The density of microvessels in LUAD is positively correlated with metastasis and recurrence. Von Willebrand factor (VWF) is a multifunctional glycoprotein in blood plasma. Recent evidence shows that VWF inhibits angiogenesis through regulation of angiopoietin-2 (Ang-2) and integrin αvβ3. LUAD patients exhibit an increase in the plasma VWF/ADAMTS-13 ratio. Gene expression profiles of LUAD tissues indicate that VWF is differentially expressed in LUAD tissues compared to normal tissues. GATA binding protein 3 (GATA3) transcription factor may mediate VWF expression in LUAD. In this review, we summarize the role of VWF in LUAD and its regulatory mechanisms. We also discuss the potential of VWF as a diagnostic indicator and therapeutic target of LUAD.

MicroRNA-218-5p affects lung adenocarcinoma progression through targeting endoplasmic reticulum oxidoreductase 1 alpha

ABSTRACT Lung adenocarcinoma (LUAD) severely threatens the health of people owing to its lethality. Nonetheless, the underlying mechanisms on LUAD development remain unclear to a great extent. This work aimed to probe the functions of miR-218-5p in LUAD. MiR-218-5p and endoplasmic reticulum oxidoreductase 1 alpha (ERO1A) were screened as differently downregulated and upregulated RNAs in LUAD, respectively, by bioinformatics analyses. The results of cell functional assays stated that enforced expression of miR-218-5p notably restrained cell viability, invasion, and migration in LUAD. MiR-218-5p may interact with 3’-untranslated region of ERO1A mRNA as analyzed by bioinformatics. Afterward, western blot and dual-luciferase reporter gene analyses were introduced to identify their interaction. ERO1A overexpression reversed the suppressive impacts of miR-218-5p on LUAD cell progression, indicating the implication of miR-218-5p/ERO1A axis in suppressing cancer development. We also observed that this regulatory axis suppressed angiogenesis in LUAD. Taken together, miR-218-5p/ERO1A axis exerted an imperative role in LUAD cell progression, which provides a valuable clue for the development of LUAD therapeutic regimen.

Membrane progesterone receptor \u03b1 (mPR\u03b1) enhances hypoxia-induced vascular endothelial growth factor secretion and angiogenesis in lung adenocarcinoma through STAT3 signaling

Lung cancer remains a huge challenge to public health because of its high incidence and mortality, and lung adenocarcinoma (LUAD) is the main subtype of lung cancer. Hypoxia-induced vascular endothelial growth factor (VEGF) release and angiogenesis have been regarded as critical events in LUAD carcinogenesis. In the present study, membrane progesterone receptor α (mPRα) is deregulated within LUAD tissue samples; increased mPRα contributes to a higher microvessel density (MVD) in LUAD tissues. mPRα knockdown in A549 and PC-9 cells significantly inhibited STAT3 phosphorylation, as well as HIF1α and VEGF protein levels, decreasing cancer cell migration and invasion. The in vivo xenograft model further confirmed that mPRα enhanced the aggressiveness of LUAD cells. Furthermore, mPRα knockdown significantly inhibited hypoxia-induced upregulation in HIF1α and VEGF levels, as well as LUAD cell migration and invasion. Under the hypoxic condition, conditioned medium (CM) derived from mPRα knockdown A549 cells, namely si-mPRα-CM, significantly inhibited HUVEC migration and tube formation and decreased VEGF level in the culture medium. In contrast, CM derived from mPRα-overexpressing A549 cells, namely mPRα-CM, further enhanced HUVEC migration and tube formation and increased VEGF level under hypoxia, which was partially reversed by STAT3 inhibitor Stattic. In conclusion, in LUAD cells, highly expressed mPRα enhances the activation of cAMP/JAK/STAT3 signaling and increases HIF1α-induced VEGF secretion into the tumor microenvironment, promoting HUVEC migration and tube formation under hypoxia.

Concurrent Blockade of Endothelial EGFR and VEGF Signaling on Malignant Associated Pleural Fluid Induced Angiogenesis: From Clinic to Bench.

Malignant-associated pleural fluid (MAPF) represented an unsolved problem in advanced lung cancer. Our previous work characterized increased pleural angiogenesis in lung adenocarcinoma and the propensity of MAPF on endothelial angiogenesis. This study investigated the combined efficacy of the tyrosine kinase inhibitor (gefitinib) and bevacizumab in opposing MAPF-induced angiogenesis. In lung adenocarcinoma patients with malignant pleural effusion (MPE), Kaplan–Meier analysis revealed the benefit of cotreatment with target therapy and bevacizumab. Increased EGFR expression was observed in the pleural microvessels of patients with lung adenocarcinoma both with and without mutations in EGFR. MAPF was obtained from lung adenocarcinoma patients both wild-type and mutant EGFRs. Total and phosphorylated EGFR were upregulated in HUVEC cultured with MAPF. Treatment with gefitinib as an EGFR inhibitor suppressed MAPF-induced endothelial migration and partially attenuated endothelial proliferation in both wild-type and mutant EGFR lung adenocarcinoma. Cotreatment with gefitinib and bevacizumab produced better inhibition of MAPF-induced endothelial angiogenesis than gefitinib alone in the mutant EGFR subgroup. Protein analysis of MAPF-derived exosomes revealed abundant EGFR and p-EGFR components that implied possible transfer to endothelial cells. Concluding Kaplan–Meier analysis and in vitro studies, the results indicated that the addition of bevacizumab on gefitinib treatment could suppress MAPF-induced angiogenesis in lung adenocarcinoma patients.

Prognostic value of Mortalin correlates with roles in epithelial-mesenchymal transition and angiogenesis in lung adenocarcinoma.

Mortalin is involved in the malignant phenotype of many cancers. However, the specific molecular mechanisms involving Mortalin in lung adenocarcinoma remain unclear. In this study, we showed that both Mortalin mRNA and protein are overexpressed in lung adenocarcinoma. In addition, Mortalin overexpression was positively correlated with poor overall survival. In vitro experiments showed that Mortalin silencing inhibited the proliferation, colony formation and migration abilities of A549 and H1299 cells. Mortalin promotes EMT progression, angiogenesis and tumor progression by activating the Wnt/β-catenin signaling pathway. In vivo experiments further confirmed that Mortalin promoted malignant progression of lung adenocarcinoma. Taken together, our data suggest that Mortalin represents an attractive prognostic marker and therapeutic target in lung adenocarcinoma patients.

Hypoxia Induces Overexpression of CCL28 to Recruit Treg Cells to Enhance Angiogenesis in Lung Adenocarcinoma.

Lung cancer is the world-leading causative factor of disease-related death. CD4+CD25+ regulatory T cells (CD4+CD25+ Treg), which are involved in immune escape of tumor cells, are highly related to tumor development and metastasis. Hypoxia induces the overexpression of chemokine (C-C motif) ligand 28 (CCL28), thus enhancing the angiogenesis and metastasis of lung adenocarcinoma. Our study revealed that most clinical lung adenocarcinoma samples showed positive expressions of HIF-lα, VEGF, FoxP3, and CCL28. More CD4+CD25+ Treg cells were detected in the cancerous samples. In addition, hypoxia increased the expression of HIF-1α and upregulated CCL28 to recruit CD4+CD25+ Treg cells; knockdown of HIF-1α could reverse this process. Treg cells also promoted invasion, migration, and angiogenesis in two human lung adenocarcinoma cell lines A549 and H1975. Our study suggested a novel potential molecular mechanism involved in the progression of lung adenocarcinoma could be a potential therapeutic target for the treatment of lung cancer.

Long non-coding RNA linc00665 interacts with YB-1 and promotes angiogenesis in lung adenocarcinoma

Angiogenesis is a core hallmark of advanced cancers, especially in lung adenocarcinoma (LUAD). However, the underlying functions and mechanisms of lncRNAs in tumor angiogenesis remain largely unknown. Here we found that linc00665 depletion could markedly depressed proliferation and capillary tube formation of HUVECs in vitro. Mechanistically, linc00665 directly interacted with YB-1 protein, enhanced its stability through inhibiting ubiquitination-dependent proteolysis and stimulated its nuclear translocation in LUAD cells. The accumulated nuclear YB-1 activated expression of ANGPT4, ANGPTL3 and VEGFA by binding to their promoters, contributing to tumor-related angiogenesis in vitro and in vivo. Collectively, we conclude that linc00665 induces tumor-related angiogenesis in LUAD by directly interacting with YB-1 and activating YB-1-ANGPT4/ANGPTL3/VEGFA axis, which provides promising anti-angiogenic targets for cancer therapy.

Long noncoding RNA MEG3 plays a promoting role in the proliferation, invasion, and angiogenesis of lung adenocarcinoma cells through the AKT pathway.

The role of long noncoding RNA maternally expressed gene 3 (MEG3) in lung adenocarcinoma has not been explored entirely. In this study, it was demonstrated that the expression of MEG3 was enhanced in lung adenocarcinoma tissues from TCGA database and some specific cell lines, while the survival analysis showed that patients with higher MEG3 levels had lower survival probabilities, which suggested that MEG3 might serve as a lung adenocarcinoma promoter. In addition, the results suggested that the overexpression of MEG3 could promote the proliferation and invasion of lung adenocarcinoma cells. Furthermore, increased MEG3 expression could result in a notable increase in angiogenesis-related factors as well as in the capillary tube formation of endothelial cells, which indicates that the overexpression of MEG3 could promote the angiogenesis of lung adenocarcinoma. From a mechanistic perspective, the results obtained revealed that the upregulation of MEG3 could stimulate the AKT signaling pathway and consequently lead to the biological behaviors mentioned above. In summary, all the results obtained from this study indicated that MEG3 plays a promoting role in the tumorigenesis and angiogenesis of lung adenocarcinoma, which deserves special attention when considered as a potential therapeutic target for lung adenocarcinoma.

Prognostic significance of IFITM1 expression and correlation with microvessel density and epithelial–mesenchymal transition signature in lung adenocarcinoma

We evaluated the relationship between interferon-induced transmembrane protein 1 (IFITM1) expression, epithelial–mesenchymal transition (EMT) signature and angiogenesis in lung adenocarcinoma. Additionally, we examined prognostic significance of IFITM1 according to pTNM stage to confirm that IFITM1 can serve as a complement to the pTNM stage. A total of 141 lung adenocarcinoma specimens were evaluated retrospectively by immunohistochemical staining for IFITM1, EMT markers (e-cadherin, β-catenin, and vimentin), and CD31 to measure microvessel density. IFITM1was expressed in 46.8% of the specimens. IFITM1 expression was significantly correlated with increased microvessel density (P = 0.048). However, IFITM1 expression was not associated with three EMT markers. In a multivariate analysis, IFITM1 was an independent prognostic factor for overall survival in a multivariate analysis (hazard ratio: 2.59, P = 0.01). Online database with data from 720 lung adenocarcinoma patients also revealed a negative prognostic significance of IFITM1 (P < 0.001). Furthermore, high IFITM1 expression was significantly correlated with decreased OS rates in each pTNM stage. IFITM1 is significantly correlated with angiogenesis and it may be used as a useful additional prognostic marker to aid pTNM classification.

The prognostic value of Tiam1 correlates with its roles in epithelial-mesenchymal transition progression and angiogenesis in lung adenocarcinoma.

BackgroundTiam1 has been identified as an oncogene and acts as an activator of GTPase Rac. Tiam1 was reported to be a promoter of cancer progression in various cancer types, while in lung adenocarcinoma, its mechanism of action is poorly understood.Materials and MethodsImmunohistochemistry staining and Western blot assay were used to determine Tiam1 expression in lung adenocarcinoma tissues, and its association with prognosis was determined by statistical analysis. We depleted Tiam1 in both A549 and H1975 cancer cell lines. Carboxyfluorescein diacetate succinimidyl ester staining and colony formation assays were used to evaluate its impact on cell proliferation ability after depletion. Transwell migration assay and wound healing assays were performed to determine its impact on migration ability of both cell lines. Western blot assay and immunofluorescence staining were used to analyze the association between Tiam1 and epithelial–mesenchymal transition (EMT) progression. Tube formation assay and vasculogenic mimicry assay were used to show the impact of Tiam1 depletion on cancer angiogenesis.ResultsIn this study, we demonstrated that Tiam1 overexpression in lung adenocarcinoma was significantly associated with advanced tumor grade and poor prognosis. In vitro assays indicated that Tiam1 depletion significantly inhibited cell proliferation, colony formation, and migration capacities in A549 and H1975 cells. Further investigations revealed that Tiam1 plays an important role in EMT program enhancement, angiogenesis, and accelerated tumor progression. Notably, Tiam1 depletion in cancer cells strongly inhibited human umbilical vein endothelial cell angiogenesis and vasculogenic mimicry capacities of both cancer cell lines.ConclusionTiam1 overexpression is associated with lung adenocarcinoma progression and may indicate poor prognosis. Tiam1 accelerated tumor progression due to EMT and angiogenesis enhancement. Our data may provide a novel therapeutic target for lung adenocarcinoma.

Extracellular Vesicles (EVs) from Lung Adenocarcinoma Cells Promote Human Umbilical Vein Endothelial Cell (HUVEC) Angiogenesis through Yes Kinase-associated Protein (YAP) Transport.

Yes kinase-associated protein (YAP) plays an important role in angiogenesis and can promote the occurrence and development of many tumor types. However, whether YAP affects tumor angiogenesis in lung cancer, and its potential mechanism in lung cancer, are unknown. In this study, we explored the role of YAP in the angiogenesis of lung adenocarcinoma, and further illustrated its possible mechanism. The expression levels of YAP and the vascular endothelial marker protein CD31 were examined by immunohistochemistry and immunofluorescence in human lung adenocarcinoma tissues, revealing a possible positive correlation between YAP and CD31 in lung adenocarcinoma. The results of the western blotting (WB) of Human Umbilical Vein Endothelial Cells (HUVECs) after coculture with lung adenocarcinoma H1975 cells, H1975 cell-supernatants and H1975-derived EVs showed that YAP derived from H1975 cells can enter HUVECs via EVs. These results were confirmed by immunofluorescence. Finally, we generated H1975 low-YAP expression cells by transfecting the cells with a shYAP lentivirus, and confirmed that the low expression of YAP in H1975 cells inhibits HUVEC angiogenesis by reducing the amount of YAP that enters HUVECs. We found, for the first time, that YAP promotes angiogenesis in lung adenocarcinoma via EVs, at least partially. Our work may provide a promising method for lung cancer treatment by targeting angiogenesis in the future.

SOX5 induces lung adenocarcinoma angiogenesis by inducing the expression of VEGF through STAT3 signaling.

Background and objectivesAngiogenesis is the main cause of lung adenocarcinoma (LAC) poor prognosis. This study aimed to investigate the effect of sex-determining region Y-box protein 5 (SOX5) expression on angiogenesis of LAC and explore its possible mechanism.Patients and methodsThe effect on angiogenesis was tested by tube formation assays using human umbilical vein endothelial cells cocultured with A549 cells. Lentivirus shRNA of SOX5 and lentivirus of SOX5 overexpression system were used to establish LAC cell lines, which expressed SOX5 of different levels. SOX5 downstream signaling targets were analyzed by real-time qPCR and Western blot. We collected 90 LAC cases and the tissues were examined by immunohistochemistry for SOX5 and vascular endothelial growth factor (VEGF).ResultsWe found that SOX5 overexpression in A549 cells significantly promoted tube formation capacity of the cocultured human umbilical vein endothelial cells. SOX5 increased VEGF expression and signal transducer activator of transcription 3 phosphorylation; however, SOX5 had no effect on extracellular signal-regulated kinase and protein kinase B pathway. Furthermore, the expression of SOX5 and VEGF had a significantly positive correlation (r=0.399, P=0.001) according to the tissue microarray data.ConclusionThese findings suggest that SOX5 induces angiogenesis by activating signal transducer activator of transcription 3/VEGF signaling and confer its candidacy as a potential therapeutic target in LAC.

Association between TAp73, p53 and VASH1 expression in lung adenocarcinoma.

TAp73 and p53 are involved in regulating tumor angiogenesis and vasohibin-1 (VASH1) is an anti-angiogenic factor. Whether TAp73 regulates angiogenesis positively or negatively is controversial. The status of P53 may determine the effect of TAp73 on angiogenesis. To the best of our knowledge it has not been previously reported whether TAp73, p53 and VASH1 are coexpressed in lung cancer. We profiled the association between TAp73 and p53 and VASH1 expression in lung adenocarcinoma (LAC) and investigated the function of TAp73 in regulating tumor angiogenesis. TAp73, p53 and VASH1 expression in 53 human LAC tissues and the adjacent normal tissues were evaluated using immunohistochemistry. The positive expression rates of p53, TAp73 and VASH1 were significantly higher (92.6, 97.7 and 67.4%, respectively) in LAC tissue compared with paraneoplastic lung tissue (7.4, 2.3 and 32.6%, respectively, P<0.01). Pearson's correlation coefficient showed a significant positive correlation between p53 and TAp73 (r=0.474, P<0.01) and TAp73α and VASH1 (r=0.367, P<0.01). The positive expression rate of p53 and VASH1 was almost significantly correlated (r=0.187, P=0.055). Similarly, p53 expression intensity had a significant positive correlation with TAp73α (r=0.517, P<0.01) and with VASH1 (r=0.277, P<0.01), as did TAp73α with VASH1 (r=0.351, P<0.01). TAp73, p53 (mutant) and VASH1 expression was significantly higher in LAC tissue compared with paraneoplastic lung tissue. The expression trends of the three proteins were significantly positively correlated with each other in LAC. These results suggest that TAp73 may suppress tumor angiogenesis in LAC.

MicroRNA-204 deregulation in lung adenocarcinoma controls the biological behaviors of endothelial cells potentially by modulating Janus kinase 2-signal transducer and activator of transcription 3 pathway.

MicroRNAs (miRNAs) have been implicated in a wide range of biological processes including angiogenesis. MiR-204 was identified as a tumor suppressor in multiple cancer types, including lung adenocarcinoma. However, the function of miR-204 in lung tumor angiogenesis remains unknown. In this study, we found that the miR-204 expression was decreased in lung adenocarcinoma based on the cancer genome atlas (TCGA) analysis and gain-of-function experiment showed that miR-204 promoted cancer cell apoptosis and suppressed cell proliferation, migration in vitro and tumor growth in vivo. Functionally, both the tube formation and migration abilities of human umbilical vein endothelial cells (HUVECs) were suppressed by conditioned media from lung cancer A549 cells with miR-204 overexpression. Meanwhile, these conditioned media inhibited proliferation and promoted apoptosis in HUVECs. The key angiogenesis inducer hypoxia inducible factor-1α (HIF1α) and the pro-angiogenic mediators vascular endothelial growth factor and platelet-derived growth factor were decreased in A549 cells transfected with miR-204 mimics. Mechanistically, miR-204 could target Janus kinase 2 (JAK2) and further impaired signal transducer and activator of transcription 3 both in vitro and in vivo. Inhibition of JAK2 or signal transducer and activator of transcription 3 (STAT3) activity with small chemical inhibitors in A549 cells impaired lung adenocarcinoma angiogenesis in vitro. Meanwhile, conditional media from interleukin 6-treated lung normal epithelial cells significantly promoted tube formation of HUVEC, which was disturbed by miR-204 overexpression. Taken together, our findings demonstrate that miR-204 attenuates angiogenesis in lung adenocarcinoma potentially via JAK2-STAT3 pathway. Clinically, the miR-204/JAK2/STAT3 signaling pathway is a putative therapeutic target in lung adenocarcinoma. © 2017 IUBMB Life, 70(1):81-91, 2018.

Hypoxia induced CCL28 promotes angiogenesis in lung adenocarcinoma by targeting CCR3 on endothelial cells.

Tumor hypoxia is one of the important features of lung adenocarcinoma. Chemokines might mediate the effects caused by tumor hypoxia. As confirmed in tumor tissue and serum of patients, CC chemokine 28 (CCL28) was the only hypoxia induced chemokine in lung adenocarcinoma cells. CCL28 could promote tube formation, migration and proliferation of endothelial cells. In addition, angiogenesis was promoted by CCL28 in the chick chorioallantoic membrane and matrigel implanted in dorsal back of athymic nude mice (CByJ.Cg-Foxn1nu/J). Tumors formed by lung adenocarcinoma cells with high expression of CCL28 grew faster and had a higher vascular density, whereas tumor formation rate of lung adenocarcinoma cells with CCL28 expression knockdown was quite low and had a lower vascular density. CCR3, receptor of CCL28, was highly expressed in vascular endothelial cells in lung adenocarcinoma when examining by immunohistochemistry. Further signaling pathways in endothelial cells, modulated by CCL28, were analyzed by Phosphorylation Antibody Array. CCL28/CCR3 signaling pathway could bypass that of VEGF/VEGFR on the levels of PI3K-Akt, p38 MAPK and PLC gamma. The effects could be neutralized by antibody against CCR3. In conclusion, CCL28, as a chemokine induced by tumor hypoxia, could promote angiogenesis in lung adenocarcinoma through targeting CCR3 on microvascular endothelial cells.