Vascular endothelial growth factor is an autocrine growth factor, signaling through neuropilin-1 in non-small cell lung cancer

Inhibition of hemangioma development by regulating the VEGF/VEGFR autocrine loop via the miR-494/PTEN pathway

BACKGROUND

Infantile hemangioma (IH) is the most common type of benign vascular tumor found in infants and young children. Hemangioma-derived endothelial cells within the lesion from birth to three months of age are the primary characteristic of IH. (hemangioma-derived endothelial cells, HemECs) proliferated rapidly and formed hemangioma masses, most of which gradually regressed spontaneously within the next 1 to 5 years of age and continued to improve until the age of 6 to 12 years. But 10-15% of IH cases can still result in ulcerative, obstructive, deformity, and even potentially fatal consequences and sequelae. These conditions seriously affect children's physical and mental health as well as their growth and development, necessitating prompt and efficient medical attention of IH is known.

OBJECTIVE

The purpose of this work. HemECs are crucial to the development of IH as a result. Not all of the pathophwork is to examine the impact of OMT on HemECs, with a specific emphasis on its role in cell migration, proliferation, cell cycle regulation, and apoptosis. Additionally, we will research the influence of OMT on the VEGFA/VEGFR-2 signaling pathway in HemECs and assess the impact of OMT on the miR-494/PTEN axis.

METHODS

The Cell Counting Kit-8 (CCK-8) assay was employed to evaluate the influence of Oxymatrine (OMT) on the proliferation of Hemangioma Endothelial Cells (HemECs). The Transwell Assay was employed to detect cell invasion and migration. The cell cycle and apoptosis were analyzed through flow cytometry. The impact of OMT on the expression of apoptosis markers (cleaved caspase-3) and proteins associated with the cell cycle (Cyclin D1, Bcl-2, Bax) was examined using Western Blot and Reverse Transcription Polymerase Chain Reaction (RT-PCR).

RESULTS

OMT treatment significantly inhibited the proliferation of HemECs, especially when combined with the miR-494 inhibitor. Additionally, OMT administration raised the proportion of cells entering the G2 phase, accelerated apoptosis, and decreased HemECs' capacity for migration and invasion. The results of Western Blot and RT-PCR demonstrated that OMT decreased the expression levels of Bax and Cleaved Caspase-3 while increasing the expression of Bcl-2 and Cyclin D1. OMT and miR-494 inhibitors have distinct impacts on the phosphorylated versions of VEGFR-2, PTEN, and ERK signaling pathways. OMT may control cell survival and proliferation through the miR-494/PTEN pathway, as evidenced by the fact that PTEN expression was dramatically upregulated in the miR-1297 inhibitor with OMT treatment group, while p-ERK expression was markedly reduced in that group.

CONCLUSIONS

OMT effectively inhibits the growth, migration, and apoptosis of hemangioma endothelial cells, likely by regulating key proteins involved in the cell cycle and apoptosis. The combination with miR-494 inhibitors enhances its therapeutic effect, suggesting a potential new approach for hemangioma treatment. These findings support the development of OMT-based strategies for hemangiomas and its potential use in cancer therapy.

Genetic Blueprints in Lung Cancer: Foundations for Targeted Therapies

Lung cancer, a malignant neoplasm originating from the epithelial cells of the lung, is characterized by its aggressive growth and poor prognosis, making it a leading cause of cancer-related mortality globally [...].

Synthesis and structural proof of novel oxazolo[5,4-d]pyrimidine derivatives as potential VEGFR2 inhibitors. In vitro study of their anticancer activity

The present study aimed to design and synthesize novel 6-N-benzyloxazolo[5,4-d]pyrimidin-7(6H)-imines 3a-j as possible inhibitors of the vascular endothelial growth factor receptor 2 (VEGFR2). The structures of newly synthesized compounds were confirmed via spectral and crystallographic data. NOESY spectroscopy was very useful in distinguishing between 6-N-benzyl-7(6H)-imine 3a and isomeric 7-N-benzyl-7-amine 4a, obtained by Dimroth rearrangement. Molecular docking at the VEGFR2 active site was performed, indicating that 7(6H)-imines should have a similar binding mode as type II VEGFR2 inhibitors. All derivatives were preliminary evaluated for in vitro cytotoxic activity against four human cancer cell lines, including lung cancer (A549), colorectal cancer (HT-29), melanoma (A375), breast cancer (MCF7), using tivozanib as a reference drug, and some of them were subjected to VEGFR2 inhibition, anti-angiogenic activity, and human serum albumin (HSA) binding assays. Only 6-N-2,4-dimethoxybenzyl derivative 3h appeared to be as active as tivozanib against all tested anticancer cell lines but equally toxic to healthy normal human dermal fibroblasts (NHDF). Derivatives 3f (6-N-2-methybenzyl) and 3b (6-N-4-methylbenzyl) have revealed slightly worse activity than 3h. They were cytotoxic agents comparable to tivozanib against three anticancer lines, but only 3b showed no cytotoxicity against NHDF. Both 3b and 3h proved to be effective VEGFR2 inhibitors with IC50 values comparable to that of tivozanib. Notably, 4a did not actually show an anticancer effect against the tested cancer lines, in contrast to isomeric 3a. In an angiogenesis assay, 3f and 3h significantly suppressed the tube formation ability of human dermal microvascular endothelial cells (HMEC-1), indicating their anti-angiogenic potential. The interactions between these compounds and HSA appeared to occur at two specific binding sites.

Long-term progression-free survival in non-small cell lung cancer patients: a spotlight on bevacizumab and its biosimilars

INTRODUCTION

In the era of immunotherapy, bevacizumab seems to be losing its place in NSCLC treatment algorithms. The aim of this work is to try to define the advantages and disadvantages of NSCLC treatment with bevacizumab in combination regimens.

AREAS COVERED

We conducted a literature search in PubMed and Google Scholar to review the most important topics regarding bevacizumab treatment in NSCLC, with or without driver mutations, including trials with checkpoint inhibitors. Special emphasis was placed on the analysis of data on the treatment of patients with CNS metastases.

EXPERT OPINION

Bevacizumab is an antiangiogenic compound whose addition to chemotherapy made the first major breakthrough in the treatment of NSCLC. However, for the last 10 years or so, the use of combination immunotherapy regimens has suppressed the use and acquisition of new knowledge about bevacizumab. Newer data are primarily related to the treatment of EGFR-positive NSCLC patients with bevacizumab, with only a few larger studies investigating the use of a combination of bevacizumab and checkpoint inhibitors. The basic task remains to define the place of bevacizumab in treatment algorithms.

Recent advances and future directions on small molecule VEGFR inhibitors in oncological conditions

"A journey of mixed emotions" is a quote that best describes the progress chart of vascular endothelial growth factor receptor (VEGFR) inhibitors as cancer therapeutics in the last decade. Exhilarated with the Food and Drug Administration (FDA) approvals of numerous VEGFR inhibitors coupled with the annoyance of encountering the complications associated with their use, drug discovery enthusiasts are on their toes with an unswerving determination to enhance the rate of translation of VEGFR inhibitors from preclinical to clinical stage. The recently crafted armory of VEGFR inhibitors is a testament to their growing dominance over other antiangiogenic therapies for cancer treatment. This review perspicuously underscores the earnest attempts of the researchers to extract the antiproliferative potential of VEGFR inhibitors through the design of mechanistically diverse structural assemblages. Moreover, this review encompasses sections on structural/molecular properties and physiological functions of VEGFR, FDA-approved VEGFR inhibitors, and hurdles restricting the activity range/clinical applicability of VEGFR targeting antitumor agents. In addition, tactics to overcome the limitations of VEGFR inhibitors are discussed. A clear-cut viewpoint transmitted through this compilation can provide practical directions to push the cart of VEGFR inhibitors to advanced-stage clinical investigations in diverse malignancies.

Cordyceps sinensis relieves non-small cell lung cancer by inhibiting the MAPK pathway

OBJECTIVE

To determine the pharmacodynamic mechanism underlying Cordyceps sinensis relief in a murine model of non-small cell lung cancer (NSCLC).

METHODS

We created a murine model of NSCLC and studied the potential molecular mechanism by which C. sinensis relieved NSCLC using a combination of transcriptomics, proteomics, and experimental validation.

RESULTS

C. sinensis markedly suppressed the fluorescence values in mice with NSCLC, improved the pathologic morphology of lung tissue, ameliorated inflammatory cytokines (tumor necrosis factor-alpha, interleukin-6, interleukin-10, and the oxidative stress indicators superoxide dismutase, malondialdehyde, and glutathione peroxidase). Transcriptomics results showed that the therapeutic effect of C. sinensis was primarily involved in the differentiation and activation of T cells. Based on the proteomic results, C. sinensis likely exerted a protective effect by recruiting immune cells and suppressing tumor cell proliferation via the MAPK pathway. Finally, the experimental validation results indicated that C. sinensis significantly decreased the VEGF and Ki67 expression, downregulated RhoA, Raf-1, and c-fos expression, which are related to cell migration and invasion, increased the serum concentration of hematopoietic factors (EPO and GM-CSF), and improved the percentage of immune cells (natural killer cells, dendritic cells, and CD4+ and CD8+ lymphocytes), which enhanced immune function.

CONCLUSIONS

Based on our preclinical study, C. sinensis was shown to exert a protective effect on NSCLC, primarily by inhibiting the MAPK pathway.

Regulation of Vascular Endothelial Growth Factor Signaling by Nicotine in a Manner Dependent on Acetylcholine-and/or β-Adrenergic-Receptors in Human Lung Cancer Cells

Simple Summary

Nicotine, a highly addictive component in cigarette smoke, facilitates tumorigenesis and the accelerated development of non-small cell lung cancer (NSCLC), which is known to account for ~80% of all lung cancer cases. This study sheds light on how the nicotine treatment of NSCLC cells regulates vascular endothelial growth factor (VEGF) signaling, known to be important in the progression of vascular disease and cancer, by acting through nicotinic acetylcholine receptors and by leading to the activation of β-adrenergic receptors through increased levels of the stress neurotransmitters, norepinephrine/noradrenaline, and epinephrine/adrenaline. Nicotine-induced activation of VEGF promoted the function of proteins involved in increased cell survival and suppressed the function of a crucial tumor suppressor, blocking cell death. This work expands our scientific knowledge of mechanisms employed by nicotine in regulating VEGF signaling in a manner dependent on the acetylcholine and/or β-adrenergic receptors, leading to lung cancer cell survival, and also provides significant insights into novel future therapeutic strategies to combat lung cancer.

Abstract

In addition to binding to nicotinic acetylcholine receptors (nAChRs), nicotine is known to regulate the β-adrenergic receptors (β-ARs) promoting oncogenic signaling. Using A549 (p53 wild-type) and H1299 (p53-null) lung cancer cells, we show that nicotine treatment led to: increased adrenaline/noradrenaline levels, an effect blocked by treatment with the α7nAChR inhibitor (α-BTX) but not by the β-blocker (propranolol) or the α4β2nAChR antagonist (DhβE); decreased GABA levels in A549 and H1299 cell media, an effect blocked by treatment with DhβE; increased VEGF levels and PI3K/AKT activities, an effect diminished by cell co-treatment with α-BTX, propranolol, and/or DhβE; and inhibited p53 activity in A549 cells, that was reversed, upon cell co-treatment with α-BTX, propranolol, and/or DhβE or by VEGF immunodepletion. VEGF levels increased upon cell treatment with nicotine, adrenaline/noradrenaline, and decreased with GABA treatment. On the other hand, the p53 activity decreased in A549 cells treated with nicotine, adrenaline/noradrenaline and increased upon cell incubation with GABA. Knockdown of p53 led to increased VEGF levels in the media of A549 cells. The addition of anti-VEGF antibodies to A549 and H1299 cells decreased cell viability and increased apoptosis; blocked the activities of PI3K, AKT, and NFκB in the absence or presence of nicotine; and resulted in increased p53 activation in A549 cells. We conclude that VEGF can be upregulated via α7nAChR and/or β-ARs and downregulated via GABA and/or p53 in response to the nicotine treatment of NSCLC cells.

The role of VEGF in cancer-induced angiogenesis and research progress of drugs targeting VEGF

Angiogenesis is a double-edged sword; it is a mechanism that defines the boundary between health and disease. In spite of its central role in physiological homeostasis, it provides the oxygen and nutrition needed by tumor cells to proceed from dormancy if pro-angiogenic factors tip the balance in favor of tumor angiogenesis. Among pro-angiogenic factors, vascular endothelial growth factor (VEGF) is a prominent target in therapeutic methods due to its strategic involvement in the formation of anomalous tumor vasculature. In addition, VEGF exhibits immune-regulatory properties which suppress immune cell antitumor activity. VEGF signaling through its receptors is an integral part of tumoral angiogenic approaches. A wide variety of medicines have been designed to target the ligands and receptors of this pro-angiogenic superfamily. Herein, we summarize the direct and indirect molecular mechanisms of VEGF to demonstrate its versatile role in the context of cancer angiogenesis and current transformative VEGF-targeted strategies interfering with tumor growth.

Molecular Mechanisms and Future Implications of VEGF/VEGFR in Cancer Therapy

Angiogenesis, the sprouting of new blood vessels from existing vessels, is one of six known mechanisms employed by solid tumors to recruit blood vessels necessary for their initiation, growth, and metastatic spread. The vascular network within the tumor facilitates the transport of nutrients, oxygen, and immune cells and is regulated by pro- and anti-angiogenic factors. Nearly four decades ago, VEGF was identified as a critical factor promoting vascular permeability and angiogenesis, followed by identification of VEGF family ligands and their receptors (VEGFR). Since then, over a dozen drugs targeting the VEGF/VEGFR pathway have been approved for approximately 20 solid tumor types, usually in combination with other therapies. Initially designed to starve tumors, these agents transiently "normalize" tumor vessels in preclinical and clinical studies, and in the clinic, increased tumor blood perfusion or oxygenation in response to these agents is associated with improved outcomes. Nevertheless, the survival benefit has been modest in most tumor types, and there are currently no biomarkers in routine clinical use for identifying which patients are most likely to benefit from treatment. However, the ability of these agents to reprogram the immunosuppressive tumor microenvironment into an immunostimulatory milieu has rekindled interest and has led to the FDA approval of seven different combinations of VEGF/VEGFR pathway inhibitors with immune checkpoint blockers for many solid tumors in the past 3 years. In this review, we discuss our understanding of the mechanisms of response and resistance to blocking VEGF/VEGFR, and potential strategies to develop more effective therapeutic approaches.

A randomized, double-blind, single-dose, parallel phase I clinical trial to compare the bioequivalence, immunogenicity and safety of bevacizumab biosimilar and bevacizumab in healthy Chinese subjects

BACKGROUND

Bevacizumab, a humanized monoclonal antibody against VEGF, can be used as a target therapy for colorectal cancer. A phase I clinical trial was conducted to compare the bioequivalence, immunogenicity and safety of bevacizumab biosimilar (Chia Tai Tianqing Pharmaceutical Group Co., Ltd.) and Bevacizumab (Roche Diagnostics GmbH) in healthy Chinese males.

RESEARCH DESIGN & METHOD

Healthy Chinese subjects (N = 98) were randomly divided into two groups. A single-dose bevacizumab biosimilar or Bevacizumab was given for per cycle. Plasma drug concentrations were detected by liquid chromatography-tandem mass spectrometry (LC-MC/MS) assay. We detected the levels of anti-drug antibody (ADA) to evaluate drug immunogenicity and the safety of drugs throughout the study.

RESULTS

The geometric mean ratios (GMRs) of AUC_0-t, C_max and AUC_0-∞ for bevacizumab biosimilar and Bevacizumab were 96.27%, 93.69% and 97.01%, respectively. The 90% CIs were all within 80%-125%, meeting the bioequivalence standards. The levels of ADA were similar. In addition, the two drugs both demonstrated excellent safety in the trial.

CONCLUSION

This study showed that bevacizumab biosimilar and Bevacizumab had similar pharmacokinetics (PK) parameters and safety in healthy Chinese subjects.

CLINICAL TRIAL REGISTRATION INFORMATION

This trial was registered in ClinicalTrials.gov (Number: NCT05476341, date registered: 25, Jul 2022) and Drug Clinical Trial Registration and Information Disclosure Platform (Number: CTR20171308, date registered: 16, Nov 2017).

Understanding the tumor microenvironment in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) represents a heterogeneous group of tumors. While significant progress has been made using multimodal treatment, the 5-year survival remains at 50%. Developing effective therapies, such as immunotherapy, will likely lead to better treatment of primary and metastatic disease. However, not all HNSCC tumors respond to immune checkpoint blockade therapy. Understanding the complex cellular composition and interactions of the tumor microenvironment is likely to lead to new knowledge for effective therapies and treatment resistance. In this review, we discuss HNSCC characteristics, predictive biomarkers, factors influencing immunotherapy response, with a focus on the tumor microenvironment.

Epithelial Stem Cells: Making, Shaping and Breaking the Niche

Epithelial stem cells maintain tissues throughout adult life and are tightly regulated by their microenvironmental niche to balance cell production and loss. These stem cells have been studied extensively as signal-receiving cells, responding to cues from other cell types and mechanical stimuli that comprise the niche. However, studies from a wide range of systems have identified epithelial stem cells as major contributors to their own microenvironment either through producing niche cells, acting directly as niche cells or regulating niche cells. The importance of stem cell contributions to the niche is particularly clear in cancer, where tumour cells extensively remodel their microenvironment to promote their survival and proliferation.

Understanding the tumor microenvironment for effective immunotherapy

Advances in immunotherapy have led to durable and long-term benefits in a subset of patients across a number of solid tumor types. Understanding of the subsets of patients that respond to immune checkpoint inhibitors at the cellular level, and in the context of their tumor microenvironment (TME) is becoming increasingly important. The TME is composed of a heterogeneous milieu of tumor and immune cells. The immune landscape of the TME can inhibit or promote tumor initiation and progression; thus, a deeper understanding of tumor immunity is necessary to develop immunotherapeutic strategies. Recent developments have focused on characterizing the TME immune contexture (type, density, and function) to discover mechanisms and biomarkers that may predict treatment outcomes. This has, in part, been powered by advancements in spatial characterization technologies. In this review article, we address the role of specific immune cells within the TME at various stages of tumor progression and how the immune contexture determinants affecting tumor growth are used therapeutically.

MicroRNA expression profiling and biomarker validation in treatment-naïve and drug resistant non-small cell lung cancer

Background

In the absence of targetable mutations or immune checkpoints, cisplatin-doublet chemotherapy remains the standard of care in non-small cell lung cancer (NSCLC). Drug resistance has however become a significant clinical challenge. Exploring a role for small non-coding microRNAs (miRNA) as biomarker candidates in cisplatin resistant (CisR) lung cancer is lacking and warrants further investigation.

Methods

miRNA expression profiling was assessed in a panel of cisplatin sensitive and resistant NSCLC cell lines and validated by qPCR. Modulation of altered miRNAs was studied using antagomiRs and pre-miRs while functional assays were used to assess cisplatin response. The translational relevance of these miRNAs as potential biomarkers was assessed in serum and matched normal and tumour lung tissues from chemo-naïve NSCLC patients, in addition to xenograft formalin-fixed paraffin-embedded (FFPE) tumours derived from cisplatin sensitive and resistant cell lines.

Results

Differential expression of a 5-miR signature (miR-30a-3p, miR-30b-5p, miR-30c-5p, miR-34a-5p, miR-4286) demonstrated their ability to distinguish between normal and tumour lung tissue and between NSCLC histologies. In squamous cell carcinoma (SqCC), tissue miRNA expression was associated with poor survival. miR-4286 showed promise as a blood-based diagnostic biomarker that could distinguish between adenocarcinoma and SqCC histologies. In a xenograft model of cisplatin resistance, using 7-9 week old female NOD/SCID mice (NOD.CB17-Prkdcscid/NCrCrl), a 5-miRNA panel showed altered expression between sensitive and resistant tumours.

Conclusions

This study identified a panel of miRNAs which may have diagnostic and prognostic potential as novel biomarkers in lung cancer and furthermore, may have a predictive role in monitoring the emergence of resistance to cisplatin.

Synthesis and anticancer potential of novel 5,6-oxygenated and/or halogenated steroidal d-homo lactones

A series of 5,6-modified steroidal d-homo lactones, comprising of halogenated and/or oxygenated derivatives, was synthesized and evaluated for potential anticancer properties. Preparation of many of these compounds involved investigating alternative synthetic pathways. In silico ADME testing was performed for both novel and some previously synthesized compounds. Calculated physicochemical properties were in accordance with the Lipinski, Veber, Egan, Ghose and Muegge criteria, suggesting the potential of these molecules as orally active agents. Cytotoxicity of the synthesized steroid derivatives was tested on six tumor and one normal human cell line. None of the investigated derivatives was toxic to non-cancerous MRC-5 control cells. Most of the compounds showed significant cytotoxicity against the treated cancer cell lines. Most notably, the 3β,5α,6β-trihydroxy derivative exhibited strong cytotoxicity against multiple cell lines (MCF-7, MDA-MB-231 and HT-29), with the highest effect observed for lung adenocarcinoma (A549) cells, for which this steroid was more cytotoxic than all of the three commercial chemotherapeutic agents used as reference compounds. Molecular docking suggests the 3β,5α,6β-trihydroxy derivative could bind the EGFR tyrosine kinase domain with high affinity, providing a potential mechanism for its cytotoxicity via inhibition of EGFR signaling. The most active compounds were further studied for their potential to induce apoptosis by the double-staining fluorescence method; where the 5α,6β-dibromide, 5α,6β-dichloride and 3β,5α,6β-triol induced apoptotic changes in all three treated cell lines: MDA-MB-231, HT-29 and A549. To predict interactions with nuclear steroidal receptors, affinity for the ligand binding domains of ERα, ERβ and AR was measured using a yeast-based fluorescence assay. The 5β,6β-epoxide, dibromide and 5α-hydroxy-3,6-dioxo derivatives showed affinity for ERα, while the 5α-fluoro-6β-hydroxy and 3β-acetoxy-5α,6β-dihydroxy derivatives were identified as ERβ ligands. None of the tested compounds showed affinity for AR. Structure-activity relationships of selected compounds were also examined.

Mutations and mechanisms of WNT pathway tumour suppressors in cancer

Mutation-induced activation of WNT-β-catenin signalling is a frequent driver event in human cancer. Sustained WNT-β-catenin pathway activation endows cancer cells with sustained self-renewing growth properties and is associated with therapy resistance. In healthy adult stem cells, WNT pathway activity is carefully controlled by core pathway tumour suppressors as well as negative feedback regulators. Gene inactivation experiments in mouse models unequivocally demonstrated the relevance of WNT tumour suppressor loss-of-function mutations for cancer growth. However, in human cancer, a far more complex picture has emerged in which missense or truncating mutations mediate stable expression of mutant proteins, with distinct functional and phenotypic ramifications. Herein, we review recent advances and challenges in our understanding of how different mutational subsets of WNT tumour suppressor genes link to distinct cancer types, clinical outcomes and treatment strategies.

Old Player-New Tricks: Non Angiogenic Effects of the VEGF/VEGFR Pathway in Cancer

Angiogenesis has long been considered to facilitate and sustain cancer growth, making the introduction of anti-angiogenic agents that disrupt the vascular endothelial growth factor/receptor (VEGF/VEGFR) pathway an important milestone at the beginning of the 21st century. Originally research on VEGF signaling focused on its survival and mitogenic effects towards endothelial cells, with moderate so far success of anti-angiogenic therapy. However, VEGF can have multiple effects on additional cell types including immune and tumor cells, by directly influencing and promoting tumor cell survival, proliferation and invasion and contributing to an immunosuppressive microenvironment. In this review, we summarize the effects of the VEGF/VEGFR pathway on non-endothelial cells and the resulting implications of anti-angiogenic agents that include direct inhibition of tumor cell growth and immunostimulatory functions. Finally, we present how previously unappreciated studies on VEGF biology, that have demonstrated immunomodulatory properties and tumor regression by disrupting the VEGF/VEGFR pathway, now provide the scientific basis for new combinational treatments of immunotherapy with anti-angiogenic agents.

Targeting the immune milieu in gastrointestinal cancers

Gastrointestinal (GI) cancers are among the most common and lethal solid tumors worldwide. Unlike in malignancies such as lung, renal and skin cancers, the activity of immunotherapeutic agents in GI cancers has, on the whole, been much less remarkable and do not apply to the majority. Furthermore, while incremental progress has been made and approvals for use of immune checkpoint inhibitors (ICIs) in specific subsets of patients with GI cancers are coming through, in a population of 'all-comers', it is frequently unclear as to who may benefit most due to the relative lack of reliable predictive biomarkers. For most patients with newly diagnosed advanced or metastatic GI cancer, the mainstay of treatment still involves chemotherapy and/or a targeted agent however, beyond the second-line this paradigm confers minimal patient benefit. Thus, current research efforts are concentrating on broadening the applicability of ICIs in GI cancers by combining them with agents designed to beneficially remodel the tumor microenvironment (TME) for more effective anti-cancer immunity with intention of improving patient outcomes. This review will discuss the currently approved ICIs available for the treatment of GI cancers, the strategies underway focusing on combining ICIs with agents that target the TME and touch on recent progress toward identification of predictors of sensitivity to immune checkpoint blockade in GI cancers.

LncRNA TTN-AS1 promotes the progression of cholangiocarcinoma via the miR-320a/neuropilin-1 axis

Neuropilin-1 regulated by miR-320a participates in the progression of cholangiocarcinoma by serving as a co-receptor that activates multiple signaling pathways. The present study sought to investigate upstream lncRNAs that control the expression of miR-320a/neuropilin-1 axis and dissect some of the underlying mechanisms. Here we report lncRNA TTN-AS1 (titin-antisense RNA1) acts as a sponging ceRNA to downregulate miR-320a and is highly expressed in human cholangiocarcinoma tissues and cells. The expression of the above three molecules is correlated with the clinicopathologic parameters of cholangiocarcinoma patients. In this study, multiple bioinformatics tools and databases were employed to seek potential lncRNAs that have binding sites with miR-320a and TTN-AS1 was identified because it exhibited the largest folds of alteration between cholangiocarcinoma and normal bile duct epithelial cells. The regulatory role of TTN-AS1 on miR-320a was further evaluated by luciferase reporter and RNA pulldown assays, coupled with in situ hybridization and RNA immunoprecipitation analyses, which showed that TTN-AS1 bound to miR-320a through an argonaute2-dependent RNA interference pathway in the cytoplasm of cholangiocarcinoma cells. Knockdown and overexpression assays showed that the regulatory effect between TTN-AS1 and miR-320 was in a one-way manner. TTN-AS1 promoted the proliferation and migration of cholangiocarcinoma cells via the miR-320a/ neuropilin-1 axis. The function of TTN-AS1 on tumor growth and its interaction with miR-320a were confirmed in animal models. Further mechanistic studies revealed that TTA-AS1, through downregulating miR-320a, promoted cell cycle progression, epithelial-mesenchymal transition, and tumor angiogenesis by upregulating neuropilin-1, which co-interacted with the hepatocyte growth factor/c-Met and transforming growth factor (TGF)-β/TGF-β receptor I pathways. In conclusion, the present results demonstrate that lncRNA TTA-AS1 is a sponging ceRNA for miR-320a, which in turn downregulates neuropilin-1 in cholangiocarcinoma cells, indicating these three molecules represent potential biomarkers and therapeutic targets in the management of cholangiocarcinoma.

NRP1 is a Prognostic Factor and Promotes the Growth and Migration of Cells in Intrahepatic Cholangiocarcinoma

Background

Neuropilin-1 (NRP-1) participates in cancer cell proliferation and metastasis as a multifunctional co-receptor by interacting with multiple signaling pathways. However, few studies have addressed the precise function and prognosis analysis of NRP1 in intrahepatic cholangiocarcinoma (ICC). We aimed to study the correlations between NRP1 and clinicopathological characteristics and NRP1 effect on ICC cell line functions.

Methods

NRP1 mRNA and its protein levels in human ICC tissues and cell lines were detected by IHC, qRT-PCR, and WB method. Transwell, wound healing, and CCK-8 assays were performed to verify the effects of NRP1 knockdown and overexpression on cell migration and proliferation capability.

Results

NRP1 proteins and mRNA levels increased in ICC tissues compared to those in paired adjacent non-tumor tissues. High NRP1 expression of ICC tissues was related to poor prognosis. NRP1 expression level was expected to be an independent prognosticator for overall survival and cumulative tumor recurrence, and was closely related to tumor number (P=0.047). Knockdown of NRP1 inhibited cell proliferation and migration capability of RBE cells in vitro, and NRP1 overexpression in 9810 cells accelerated proliferation and migration. Additionally, NRP1 may promote cell proliferation and migration in ICC via the FAK/PI3-K/AKT pathway.

Conclusion

As an oncogene, NRP1 may function as a candidate target and prognostic biomarker of value for ICC therapy.

Nei Endonuclease VIII-like 2 Gene rs8191670 Polymorphism affects the Sensitivity of Non-small Cell Lung Cancer to Cisplatin by binding with MiR-548a

Background: Nei endonuclease VIII-like 2 (NEIL2) is a gene encoding DNA repair enzyme, which is involved in the base excision repair (BER) pathway in mammalian cells. Cisplatin is a common cytotoxic anti-tumor agent in clinic by destroying normal structure of DNA and inducing cell apoptosis. However, how NEIL2 affects the sensitivity of NSCLC to cisplatin is still unclear. Methods: The clinical data from 206 patients diagnosed pathologically were collected. The DNA sequencing of NEIL2 gene 3'UTR and the PFS curve of NSCLC patients receiving cisplatin-based chemotherapy were performed. Western blot analysis and immunohistochemistry were used to detect NEIL2 protein expression. Human NSCLC cell lines A549 and H1299 were cultured and evaluated for cell viability. RT-PCR was performed for quantitative detection of miR-548a. 3'UTR reporter plasmid was constructed and luciferase reporter assay was used to verify the target gene regulated by miR-548a. Results: In this study, we found that the Neil2 gene had the polymorphism (T/C) in rs8191670 and it is associated with the PFS of advanced NSCLC patients. MiR-548a targets NEIL2 3'UTR to suppress its expression. Upregulation of NEIL2 expression or downregulation of miR-548a could reduce the sensitivity of NSCLC cells to cisplatin. Conclusion: Our results demonstrated that NEIL2 gene rs8191670 polymorphism affects the PFS of advanced NSCLC patients, and the underlying molecular mechanisms may be that miR-548a can regulate NEIL2 expression by binding to its 3'UTR seed region containing rs8191670.

Neuropilin1 Expression Acts as a Prognostic Marker in Stomach Adenocarcinoma by Predicting the Infiltration of Treg Cells and M2 Macrophages

Neuropilin1 (NRP1) plays a critical role in tumor progression and immune responses. Although the roles of NRP1 in various tumors have been investigated, the clinical relevance of NRP1 expression in stomach adenocarcinoma (STAD) has not been studied. To investigate the use of NRP1 as a prognostic biomarker of STAD, we analyzed NRP1 mRNA expression and its correlation with patient survival and immune cell infiltration using various databases. NRP1 mRNA expression was significantly higher in STAD than normal tissues, and Kaplan-Meier survival analysis showed that NRP1 expression was significantly associated with poor prognosis in patients with STAD. To elucidate the related mechanism, we analyzed the correlation between NRP1 expression and immune cell infiltration level. In particular, the infiltration of immune-suppressive cells, such as regulatory T (Treg) cells and M2 macrophage, was significantly increased by NRP1 expression. In addition, the expression of interleukin (IL)-35, IL-10, and TGF-β1 was also positively correlated with NRP1 expression, resulting in the immune suppression. Collectively in this study, our integrated analysis using various clinical databases shows that the significant correlation between NRP1 expression and the infiltration of Treg cells and M2 macrophage explains poor prognosis mechanism in STAD, suggesting the clinical relevance of NRP1 expression as a prognostic biomarker for STAD patients.

Correlation of gene polymorphisms of vascular endothelial growth factor with grade and prognosis of lung cancer

Background

Vascular endothelial growth factor (VEGF) gene is highly polymorphic, and single nucleotide polymorphisms (SNP) of VEGF gene are associate with cancer prognosis. This study aimed to analyze the correlation of VEGF gene polymorphisms with grade and prognosis of lung cancer.

Methods

A total of 458 Chinese patients with primary lung cancer were enrolled from September 2008 to October 2013. The genotypes of −2578C > A, −1154G > A, − 460 T > C, and + 405G > C were analyzed in white blood cells from patients using polymerase chain reaction based restriction fragment length polymorphism.

Results

Our data showed that –1154G > A polymorphism was significantly associated with tumor stages, but all four tested VEGF gene polymorphisms had no significant effect on survival.

Conclusions

VEGF polymorphisms may relate to stage of lung cancer in Chinese population.

Biomarker-guided therapy for colorectal cancer: strength in complexity

The number of molecularly stratified treatment options available to patients with colorectal cancer (CRC) is increasing, with a parallel rise in the use of biomarkers to guide prognostication and treatment decision-making. The increase in both the number of biomarkers and their use has resulted in a progressively complex situation, evident both from the extensive interactions between biomarkers and from their sometimes complex associations with patient prognosis and treatment benefit. Current and emerging biomarkers also reflect the genomic complexity of CRC, and include a wide range of aberrations such as point mutations, amplifications, fusions and hypermutator phenotypes, in addition to global gene expression subtypes. In this Review, we provide an overview of current and emerging clinically relevant biomarkers and their role in the management of patients with CRC, illustrating the intricacies of biomarker interactions and the growing treatment opportunities created by the availability of comprehensive molecular profiling.

Targeting signalling pathways and the immune microenvironment of cancer stem cells - a clinical update

Cancer stem cells (CSCs) have important roles in tumour development, relapse and metastasis; the intrinsic self-renewal characteristics and tumorigenic properties of these cells provide them with unique capabilities to resist diverse forms of anticancer therapy, seed recurrent tumours, and disseminate to and colonize distant tissues. The findings of several studies indicate that CSCs originate from non-malignant stem or progenitor cells. Accordingly, inhibition of developmental signalling pathways that are crucial for stem and progenitor cell homeostasis and function, such as the Notch, WNT, Hedgehog and Hippo signalling cascades, continues to be pursued across multiple cancer types as a strategy for targeting the CSCs hypothesized to drive cancer progression - with some success in certain malignancies. In addition, with the renaissance of anticancer immunotherapy, a better understanding of the interplay between CSCs and the tumour immune microenvironment might be the key to unlocking a new era of oncological treatments associated with a reduced propensity for the development of resistance and with enhanced antimetastatic activity, thus ultimately resulting in improved patient outcomes. Herein, we provide an update on the progress to date in the clinical development of therapeutics targeting the Notch, WNT, Hedgehog and Hippo pathways. We also discuss the interactions between CSCs and the immune system, including the potential immunological effects of agents targeting CSC-associated developmental signalling pathways, and provide an overview of the emerging approaches to CSC-targeted immunotherapy.

A novel 2-aminobenzimidazole-based compound Jzu 17 exhibits anti-angiogenesis effects by targeting VEGFR-2 signalling

BACKGROUND AND PURPOSE

Recent development in drug discovery have shown benzimidazole to be an important pharmacophore,. Benzimidazole derivatives exhibit broad-spectrum pharmacological properties including anti-microbial, anti-diabetic and anti-tumour activity. However, whether benzimidazole derivatives are effective in suppressing angiogenesis and its underlying mechanisms remain incompletely understood. In this study, we aim to characterize the anti-angiogenic mechanisms of a novel 2-aminobenzimidazole-based compound, Jzu 17, in an effort to develop novel angiogenesis inhibitor.

EXPERIMENTAL APPROACH

Effects of Jzu 17 on endothelial cell proliferation, migration, invasion, and activation of signalling molecules induced by VEGF-A, were analysed by immunoblotting, MTT, BrdU, migration, and invasion assays. We performed tube formation assay, aorta ring sprouting assay, matrigel plug assay, and a mouse model of metastasis to evaluate ex vivo and in vivo anti-angiogenic effects of Jzu 17.

KEY RESULTS

Jzu 17 inhibited VEGF-A-induced cell proliferation, migration, invasion, and endothelial tube formation of HUVECs. Jzu 17 suppressed VEGF-A-induced microvessel sprouting ex vivo and attenuated VEGF-A- or tumour cell-induced neovascularization in vivo. Jzu 17 also reduced B16F10 melanoma lung metastasis. In addition, Jzu 17 inhibited the phosphorylation of VEGFR-2 and its downstream signalling molecules in VEGF-A-stimulated HUVECs. Results from computer modelling further showed that Jzu 17 binds to VEGFR-2 with high affinity.

CONCLUSIONS AND IMPLICATIONS

Jzu 17 may inhibit endothelial remodelling and suppress angiogenesis through targeting VEGF-A-VEGFR-2 signalling. These results also suggest Jzu 17 as a potential lead compound and warrant the clinical development of similar agents in the treatment of cancer and angiogenesis-related diseases.

The miR-141/neuropilin-1 axis is associated with the clinicopathology and contributes to the growth and metastasis of pancreatic cancer

BACKGROUND

Neuropilin-1 (NRP-1) is a non-tyrosine kinase receptor interacting with multiple signaling pathways that underpin the biological behavior and fate of cancer cells. However, in pancreatic cancer, the mechanisms underlying the function of NRP-1 in cell proliferation and metastasis and the involvement of regulatory upstream miRNAs remain unclear.

METHODS

Potential miRNAs were mined by using multiple bioinformatics prediction tools and validated by luciferase assays. The expression of NRP-1 and miRNA-141 (miR-141) in pancreatic tissues and cells was examined by immunohistochemistry, immunoblotting and/or real-time RT-PCR. Stable transfected cells depleted of NRP-1 were generated, and regulatory effects of miR-141 were investigated by transfecting cells with miR-141 mimics and anti-miR-141. Assays of cell viability, proliferation, cell cycle distribution, transwell migration and cell scratch were employed. Xenograft tumor models were established to assess the effects of NRP-1 depletion on tumorigenesis and liver metastasis, and therapeutic effects of miR-141 on tumor growth. The role of miR-141/NRP-1 axis in regulating epithelial-mesenchymal transition (EMT) by co-interacting the TGF-β pathway was examined.

RESULTS

In this study, of 12 candidate miRNAs identified, miR-141 showed the strongest ability to regulate NRP-1. In pancreatic cancer tissues and cells, the expression level of NRP-1 was negatively correlated with that of miR-141. NRP-1 was highly expressed in pancreatic cancer tissues compared with normal pancreatic tissues, and its expression levels were positively correlated with tumor grade, lymph metastasis and AJCC staging. NRP-1 depletion inhibited cell proliferation by inducing cell cycle arrest at the G0/G1 phase through upregulating p27 and downregulating cyclin E and cyclin-dependent kinase 2, and reduced cell migration by inhibiting EMT through upregulating E-cadherin and downregulating Snail and N-cadherin. Through downregulating NRP-1, miR-141 mimics showed a similar effect as NRP-1 depletion on cell proliferation and migration. NRP-1 depletion suppressed tumor growth and liver metastasis and miR-141 mimics inhibited the growth of established tumors in mice. NRP-1 depletion and/or miR-141 mimics inhibited the activation of the TGF-β pathway stimulated by TGF-β ligand.

CONCLUSIONS

The present results indicate that NRP-1 is negatively regulated by miR-141 and the miR-141/NRP-1 axis may serve as potentially valuable biomarkers and therapeutic targets for pancreatic cancer.

Neuropilin-1 is associated with the prognosis of cervical cancer in Henan Chinese population

Objective: Neuropilin-1 has been reported to be a valuable diagnostic biomarker in patients with cervical intraepithelial neoplasia (CIN) and early cervical cancer. The aim of this study was to investigate the association between Neuropilin-1 and the prognosis of cervical cancer in Henan Chinese population.

Methods: Tissues were collected in The Third Affiliated Hospital of Zhengzhou University between 2010 and 2012, determining the level and expression of Neuropilin-1 in different cervical lesions by immunohistochemistry. The cell proliferation assay, wound-healing assays and Transwell assay were performed to explore the ability of proliferation, migration and invasion for Hela and Caski cells after NRP-1 was knocked down by shRNA transfection. Western blotting was performed to investigate the role of NRP-1 in endothelial-to-mesenchymal transition (EndMT). Tumor xenografts model was used to evaluate the effect of NRP-1 on the tumor growth.

Results: The expression of NRP-1 was upregulated in the tumor tissues compared with the CIN and normal tissues (P<0.0001). The overall survival time of the high NRP-1 expression group was significantly shorter than that of the low NRP-1 expression group (P<0.0001); NRP-1-depleted cells had dramatically lower rate of proliferation, migration and invasion compared to control cells (all P<0.05). Depletion of NRP-1 significantly suppressed the growth of CaSki xenograft tumor in nude mice.

Conclusions: The current study demonstrated that NRP-1 expression is significantly correlated with the progression of CC. Notably, high NRP-1 expression is correlated with a poorer survival in patients with CC, and has been shown to be an independent prognostic factor.

Suppressing glucose metabolism with epigallocatechin-3-gallate (EGCG) reduces breast cancer cell growth in preclinical models

Numerous studies propose that epigallocatechin-3-gallate (EGCG), an abundant polyphenol in green tea, has anti-cancer properties. However, its mechanism of action in breast cancer remains unclear. This study investigated the capacity of EGCG to suppress breast cancer cell growth in vitro and in vivo, characterizing the underlying mechanisms, focusing on the effect of EGCG on glucose metabolism. EGCG reduced breast cancer 4T1 cell growth in a concentration- (10-320 μM) and time- (12-48 h) dependent manner. EGCG induced breast cancer apoptotic cell death at 24 h, as evidenced by annexin V/PI, caspase 3, caspase 8 and caspase 9 activation. Furthermore, EGCG affected the expression of 16 apoptosis-related genes, and promoted mitochondrial depolarization. EGCG induced autophagy concentration-dependently in 4T1 cells by modulating the levels of the autophagy-related proteins Beclin1, ATG5 and LC3B. Moreover, EGCG affected glucose, lactate and ATP levels. Mechanistically, EGCG significantly inhibited the activities and mRNA levels of the glycolytic enzymes hexokinase (HK), phosphofructokinase (PFK), and lactic dehydrogenase (LDH), and to a lesser extent the activity of pyruvate kinase (PK). In addition, EGCG decreased the expression of hypoxia-inducible factor 1α (HIF1α) and glucose transporter 1 (GLUT1), critical players in regulating glycolysis. In vivo, EGCG reduced breast tumor weight in a dose-dependent manner, reduced glucose and lactic acid levels and reduced the expression of the vascular endothelial growth factor (VEGF). In conclusion, EGCG exerts an anti-tumor effect through the inhibition of key enzymes that participate in the glycolytic pathway and the suppression of glucose metabolism.

OVA66 promotes tumour angiogenesis and progression through enhancing autocrine VEGF-VEGFR2 signalling

Background

Activation of autocrine VEGF-VEGFR2 signalling in tumour cells activates cell proliferation, survival, and angiogenesis, all of which are crucial for tumour progression. Ovarian cancer-associated antigen 66 (OVA66) is now known to be overexpressed in multiple tumours and plays a role in tumour development, but the underlying mechanisms has not been fully investigated.

Methods

We employed ovarian and cervical cancer cells and mouse models to detect the role of OVA66 in angiogenesis, growth, and metastasis of cancer cells. Immunofluorescence and western blot were used to determine the function of OVA66 in regulating autocrine VEGF-VEGFR2 signalling. Immunohistochemistry and bioinformatics analysis were used to detect the correlation of OVA66 and VEGF expression.

Findings

OVA66 overexpression in the cancer cell lines promoted VEGF secretion, tumour growth and angiogenesis in vitro and in vivo. Conversely, shRNA-mediated OVA66 knockdown had the opposite effects. Mechanistically, OVA66 overexpression was found to boost an autocrine VEGF–VEGFR2 positive-feedback signalling loop in the tumour cells, leading to amplified effect of VEGF on tumour angiogenesis and proliferation and increased migration in vitro and in vivo, respectively. Finally, we identified a significant positive correlation between the expression levels of OVA66 and VEGF in ovarian and cervical cancer specimens, and found that OVA66 was significantly associated with advanced ovarian cancer.

Interpretation

We identify a novel function for OVA66 in regulating an autocrine VEGF–VEGFR2 feed-forward signalling loop that promotes tumour progression and angiogenesis.

Fund

This work was supported by the National Natural Science Foundation of China (81602262); and Excellent Youth Scholar Program of Tongji University (2015KJ062).

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OVA66 promotes VEGF secretion and angiogenesis of ovarian and cervical cancer cells in vitro and in vivo.

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OVA66 enhances activation of autocrine VEGF-VEGFR2 signalling.

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OVA66 amplifies VEGF-induced angiogenesis and proliferation of ovarian and cervical cancer cells.

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OVA66 can promote migratory potential of ovarian and cervical cancer cells by enhancing autocrine VEGF-VEGFR2 signalling.

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Expression level of OVA66 positively correlated with VEGF expression significantly in ovarian and cervical cancer patients.

Bifunctional Duocarmycin Analogues as Inhibitors of Protein Tyrosine Kinases

Bifunctional duocarmycin analogues are highly cytotoxic compounds that have been shown to be irreversible aldehyde dehydrogenase 1 inhibitors. Interestingly, cells with low aldehyde dehydrogenase 1 expression are also sensitive to bifunctional duocarmycin analogues, suggesting the existence of another target. Through in silico approaches, including principal component analysis, structure-similarity search, and docking calculations, protein tyrosine kinases, and especially the vascular endothelial growth factor receptor 2 (VEGFR-2), were predicted as targets of bifunctional duocarmycin analogues. Biochemical validation was performed in vitro, confirming the in silico results. Structural optimization was performed to mainly target VEGFR-2, but not aldehyde dehydrogenase 1. The optimized bifunctional duocarmycin analogue was synthesized. In vitro assays revealed this bifunctional duocarmycin analogue as a strong inhibitor of VEGFR-2, with low residual aldehyde dehydrogenase 1 activity. Altogether, studies revealed bifunctional duocarmycin analogues as a new class of naturally derived compounds that express a very high cytotoxicity to cancer cells overexpressing aldehyde dehydrogenase 1 as well as VEGFR-2.

Quadruplex-forming oligonucleotide targeted to the VEGF promoter inhibits growth of non-small cell lung cancer cells

BACKGROUND

Vascular endothelial growth factor (VEGF) is commonly overexpressed in a variety of tumor types including lung cancer. As a key regulator of angiogenesis, it promotes tumor survival, growth, and metastasis through the activation of the downstream protein kinase B (AKT) and extracellular signal-regulated kinase (ERK 1/2) activation. The VEGF promoter contains a 36 bp guanine-rich sequence (VEGFq) which is capable of forming quadruplex (four-stranded) DNA. This sequence has been implicated in the down-regulation of both basal and inducible VEGF expression and represents an ideal target for inhibition of VEGF expression.

RESULTS

Our experiments demonstrate sequence-specific interaction between a G-rich quadruplex-forming oligonucleotide encoding a portion of the VEGFq sequence and its double stranded target sequence, suggesting that this G-rich oligonucleotide binds specifically to its complementary C-rich sequence in the genomic VEGF promoter by strand invasion. We show that treatment of A549 non-small lung cancer cells (NSCLC) with this oligonucleotide results in decreased VEGF expression and growth inhibition. The VEGFq oligonucleotide inhibits proliferation and invasion by decreasing VEGF mRNA/protein expression and subsequent ERK 1/2 and AKT activation. Furthermore, the VEGFq oligonucleotide is abundantly taken into cells, localized in the cytoplasm/nucleus, inherently stable in serum and intracellularly, and has no effect on non-transformed cells. Suppression of VEGF expression induces cytoplasmic accumulation of autophagic vacuoles and increased expression of LC3B, suggesting that VEGFq may induce autophagic cell death.

CONCLUSION

Our data strongly suggest that the G-rich VEGFq oligonucleotide binds specifically to the C-rich strand of the genomic VEGF promoter, via strand invasion, stabilizing the quadruplex structure formed by the genomic G-rich sequence, resulting in transcriptional inhibition. Strand invading oligonucleotides represent a new approach to specifically inhibit VEGF expression that avoids many of the problems which have plagued the therapeutic use of oligonucleotides. This is a novel approach to specific inhibition of gene expression.

Salvianolic acid B as an anti-emphysema agent I: In vitro stimulation of lung cell proliferation and migration, and protection against lung cell death, and in vivo lung STAT3 activation and VEGF elevation

Emphysema causes progressive and life-threatening alveolar structural destruction/loss, yet remains irreversible and incurable to date. Impaired vascular endothelial growth factor (VEGF) signaling has been proposed as a new pathogenic mechanism, and if so, VEGF recovery may enable reversal of emphysema. Thus, we hypothesized that salvianolic acid B (Sal-B), a polyphenol in traditional Chinese herbal danshen, is an alveolar structural recovery agent for emphysema by virtue of VEGF stimulation/elevation via activation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), as stimulating lung cell proliferation and migration, and protecting against lung cell death. Using in vitro human lung microvascular endothelial (HMVEC-L) and alveolar epithelial (A549) cell systems, Sal-B was examined for 1) stimulation of cell proliferation by the MTT and BrdU assays; 2) promotion of cell migration by the scratch wound closure assay; 3) protection against emphysema-like induced cell death by the trypan blue exclusion and flow cytometry assays; and 4) mechanistic involvement of JAK2/STAT3/VEGF in these activities. Sal-B was also spray-dosed to the lungs of healthy rats for two weeks to verify the lung's STAT3 activation and VEGF elevation by western blot, as well as the absence of functional and morphological abnormalities. All the in vitro cell-based activities were concentration-dependent. At 25 μM, Sal-B 1) stimulated cell proliferation by 1.4-2.6-fold; 2) promoted migratory cell wound closure by 1.5-1.7-fold; and 3) protected against cell death induced with H₂O₂ (oxidative stress) and SU5416 (VEGF receptor blockade) by 49-86%. JAK2 and STAT3 inhibitors and VEGF receptor antagonist each opposed these Sal-B's activities by over 65%, suggesting the mechanistic involvement of JAK2/STAT3 activation and VEGF stimulation/elevation. In rats, Sal-B at 0.2 mg/kg enabled 1.9 and 1.5-fold increased STAT3 phosphorylation and VEGF elevation in the lungs, respectively, while causing no functional and morphological abnormalities. Hence, Sal-B was projected to be a new class of anti-emphysema agent capable of reversing alveolar structural destruction/loss via JAK2/STAT3/VEGF-dependent stimulation of lung cell proliferation and migration, and inhibition of induced lung cell death.

Neuropilin-1 upregulation elicits adaptive resistance to oncogene-targeted therapies

Cancer cell dependence on activated oncogenes is therapeutically targeted, but acquired resistance is virtually unavoidable. Here we show that the treatment of addicted melanoma cells with BRAF inhibitors, and of breast cancer cells with HER2-targeted drugs, led to an adaptive rise in neuropilin-1 (NRP1) expression, which is crucial for the onset of acquired resistance to therapy. Moreover, NRP1 levels dictated the efficacy of MET oncogene inhibitors in addicted stomach and lung carcinoma cells. Mechanistically, NRP1 induced a JNK-dependent signaling cascade leading to the upregulation of alternative effector kinases EGFR or IGF1R, which in turn sustained cancer cell growth and mediated acquired resistance to BRAF, HER2, or MET inhibitors. Notably, the combination with NRP1-interfering molecules improved the efficacy of oncogene-targeted drugs and prevented or even reversed the onset of resistance in cancer cells and tumor models. Our study provides the rationale for targeting the NRP1-dependent upregulation of tyrosine kinases, which are responsible for loss of responsiveness to oncogene-targeted therapies.

Neuropilin-1 regulated by miR-320 contributes to the growth and metastasis of cholangiocarcinoma cells

BACKGROUND & AIMS

Neuropilin-1 (NRP-1) activates signalling pathways as multifunctional co-receptors in cancer cells. However, its role and how it is regulated by miRNAs in cholangiocarcinoma (CCA) have not yet been investigated.

METHODS

The expression of NRP-1, miR-320 and key molecules involved in cell proliferation, migration and related signalling pathways were detected by immunohistochemistry, immunoblotting and qRT-PCR. Stable transfectants depleted of NRP-1 were generated. The regulatory effect of miR-320 on NRP-1 was evaluated by luciferase reporter assays. Cell proliferation, cell cycle distribution and migration were examined. Xenograft tumour models were established to assess tumourigenesis, tumour growth and lung metastasis.

RESULTS

Cholangiocarcinoma tissues expressed higher levels of NRP-1 than adjacent normal biliary tissues, and its expression negatively correlated with miR-320. NRP-1 depletion inhibited cell proliferation and induced cell cycle arrest in the G1/S phase by upregulating p27, and downregulating cyclin E and cyclin-dependent kinase 2; and reduced cell migration by inhibiting the phosphorylation of focal adhesion kinase. NRP-1 depletion suppressed tumourigenesis, tumour growth and lung metastasis by inhibiting cell proliferation and tumour angiogenesis in experimental animals. Depletion of NRP-1 inhibited the activation of VEGF/VEGFR2, EGF/EGFR and HGF/c-Met pathways stimulated by respective ligands. MiR-320 negatively regulated the expression of NRP-1 by binding to the 3'-UTR of NRP-1 promoter, and miR-320 mimics inhibited cell proliferation and migration, and the growth of established tumours in animals by downregulating NRP-1.

CONCLUSIONS

The present results indicate that NRP-1 is negatively regulated by miR-320, and both of them may be potentially therapeutic targets for CCA.

MALDI mass spectrometry imaging of erlotinib administered in combination with bevacizumab in xenograft mice bearing B901L, EGFR-mutated NSCLC cells

Combination therapy of erlotinib plus bevacizumab improves progression-free survival of patients with epidermal growth factor receptor–mutated (EGFR-mutated) advanced non–small-cell lung cancer (NSCLC) compared with erlotinib alone. Although improved delivery and distribution of erlotinib to tumours as a result of the normalization of microvessels by bevacizumab is thought to be one of the underlying mechanisms, there is insufficient supporting evidence. B901L cells derived from EGFR-mutated NSCLC were subcutaneously implanted into mice, and mice were treated with bevacizumab or human IgG followed by treatment with erlotinib. The distribution of erlotinib in their tumours at different times after erlotinib administration was analysed by matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI). We also analysed the distribution of erlotinib metabolites and the distribution of erlotinib in tumours refractory to erlotinib, which were established by long-term treatment with erlotinib. We found that erlotinib was broadly diffused in the tumours from B901L-implanted xenograft mice, independently of bevacizumab treatment. We also found that erlotinib metabolites were co-localized with erlotinib and that erlotinib in erlotinib-refractory tumours was broadly distributed throughout the tumour tissue. Multivariate imaging approaches using MALDI MSI as applied in this study are of great value for pharmacokinetic studies in drug development.

NRP1-positive lung cancer cells possess tumor-initiating properties

Tumor-initiating cells possess the capacity for self-renewal and to create heterogeneous cell lineages within a tumor. Therefore, the identification and isolation of cancer stem cells is an essential step in the analysis of their biology. The aim of the present study was to determine whether the cell surface protein neuropilin 1 (NRP1) can be used as a biomarker of stem-like cells in lung cancer tumors. For this purpose, NRP1-negative (NRP1-) and NRP1-positive (NRP1+) cell subpopulations from two lung cancer cell lines were sorted by flow cytometry. The NRP1+ cell subpopulation showed an increased expression of pluripotency markers OCT-4, Bmi-1 and NANOG, as well as higher cell migration, clonogenic and self-renewal capacities. NRP1 gene knockdown resulted not only in a decreased expression of stemness markers but also in a decrease in the clonogenic, cell migration and self-renewal potential. In addition, the NRP1+ cell subpopulation exhibited dysregulated expression of epithelial-to-mesenchymal transition-associated genes, including the ΔNp63 isoform protein, a previously reported characteristic of cancer stem cells. Notably, a genome-wide expression analysis of NRP1-knockdown cells revealed a potential new NRP1 pathway involving OLFML3 and genes associated with mitochondrial function. In conclusion, we demonstrated that NRP1+ lung cancer cells have tumor-initiating properties. NRP1 could be a useful biomarker for tumor-initiating cells in lung cancer tumors.

Genetic status of KRAS modulates the role of Neuropilin-1 in tumorigenesis

Neuropilin-1 (NRP1), a non-tyrosine kinase receptor, is overexpressed in many cancers including pancreatic and lung cancers. Inhibition of NRP1 expression, however, has differing pro-tumor vs. anti-tumor effects, depending on the cancer types. To understand the differential role of NRP1 in tumorigenesis process, we utilized cells from two different cancer types, pancreatic and lung, each containing either wild type KRAS (KRAS ^wt) or mutant KRAS (KRAS ^mt). Inhibition of NRP1 expression by shRNA in both pancreatic and lung cancer cells containing dominant active KRAS ^mt caused increased cell viability and tumor growth. On the contrary, inhibition of NRP1, in the tumor cells containing KRAS ^wt showed decreased tumor growth. Importantly, concurrent inhibition of KRAS ^mt and NRP1 in the tumor cells reverses the increased viability and leads to tumor inhibition. We found that NRP1 shRNA expressing KRAS ^mt tumor cells caused increased cell viability by decreasing SMAD2 phosphorylation. Our findings demonstrate that the effects of NRP1 knockdown in cancer cells are dependent on the genetic status of KRAS.

VEGF as a potential target in lung cancer

Introduction The vascular endothelial growth factor A (VEGF) is the main mediator of angiogenesis. In addition, VEGF contributes to cancer growth and metastasis directly targeting tumor cells. VEGF overexpression and/or high VEGF serum levels have been reported in lung cancer. Areas covered We searched Pubmed for relevant preclinical studies with the terms 'lung cancer' 'VEGF' and 'in vivo'. We also searched the Clinicaltrials.gov database, the FDA and the EMA websites for the most recent updates on clinical development of anti-VEGF agents. Expert opinion VEGF plays an important role in sustaining the development and progression of lung cancer and it might represent an attractive target for therapeutic strategies. Nevertheless, clinical trials failed to attend the promising expectations deriving from preclinical studies with anti-VEGF agents. To improve the efficacy of anti-VEGF therapies in lung cancer, potential strategies might be the employment of combinatory therapies with immune checkpoint inhibitors or agents that inhibit signaling pathways and proangiogenic factors activated in response to VEGF blockade, and the identification of novel targets in the VEGF cascade. Finally, the identification of predictive markers might help to select patients who are more likely to respond to anti-angiogenic drugs.

Antifibrotic role of vascular endothelial growth factor in pulmonary fibrosis

The chronic progressive decline in lung function observed in idiopathic pulmonary fibrosis (IPF) appears to result from persistent nonresolving injury to the epithelium, impaired restitution of the epithelial barrier in the lung, and enhanced fibroblast activation. Thus, understanding these key mechanisms and pathways modulating both is essential to greater understanding of IPF pathogenesis. We examined the association of VEGF with the IPF disease state and preclinical models in vivo and in vitro. Tissue and circulating levels of VEGF were significantly reduced in patients with IPF, particularly in those with a rapidly progressive phenotype, compared with healthy controls. Lung-specific overexpression of VEGF significantly protected mice following intratracheal bleomycin challenge, with a decrease in fibrosis and bleomycin-induced cell death observed in the VEGF transgenic mice. In vitro, apoptotic endothelial cell–derived mediators enhanced epithelial cell injury and reduced epithelial wound closure. This process was rescued by VEGF pretreatment of the endothelial cells via a mechanism involving thrombospondin-1 (TSP1). Taken together, these data indicate beneficial roles for VEGF during lung fibrosis via modulating epithelial homeostasis through a previously unrecognized mechanism involving the endothelium.

Elevated VEGF is associated with less severe disease in IPF patients, and VEGF overexpression ameliorates bleomycin-induced lung fibrosis in a murine model.

Structural optimization and evaluation of novel 2-pyrrolidone-fused (2-oxoindolin-3-ylidene)methylpyrrole derivatives as potential VEGFR-2/PDGFRβ inhibitors

Background

Tumor angiogenesis, essential for tumor growth and metastasis, is tightly regulated by VEGF/VEGFR and PDGF/PDGFR pathways, and therefore blocking those pathways is a promising therapeutic target. Compared to sunitinib, the C(5)-Br derivative of 2-pyrrolidone-fused (2-oxoindolin-3-ylidene)methylpyrrole has significantly greater in vitro activities against VEGFR-2, PDGFRβ, and tube formation.

Results and discussion

The objective of this study was to perform further structural optimization, which revealed certain new products with even more potent anti-tumor activities, both cellularly and enzymatically. Of these, 15 revealed ten- and eightfold stronger potencies against VEGFR-2 and PDGFRβ than sunitinib, respectively, and showed selectivity against HCT116 with a favorable selective index (SI > 4.27). The molecular docking results displayed that the ligand–protein binding affinity to VEGFR-2 could be enhanced by introducing a hydrogen-bond-donating (HBD) substituent at C(5) of (2-oxoindolin-3-ylidene)methylpyrrole such as 14 (C(5)-OH) and 15 (C(5)-SH).

Conclusions

Among newly synthetic compounds, 7 and 13–15 exhibited significant inhibitory activities against VEGFR-2 and PDGFRβ. Of these, the experimental results suggest that 15 might be a promising anti-proliferative agent. Graphical abstract

Bevacizumab counteracts VEGF-dependent resistance to erlotinib in an EGFR-mutated NSCLC xenograft model

Erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), shows superior efficacy in patients with non-small cell lung cancer (NSCLC) harboring activating EGFR mutations (EGFR Mut⁺). However, almost all tumors eventually develop resistance to erlotinib. Recently, the Phase II JO25567 study reported significant prolongation of progression-free survival (PFS) by erlotinib plus bevacizumab combination compared with erlotinib in EGFR Mut⁺ NSCLC. Herein, we established a preclinical model which became refractory to erlotinib after long-term administration and elucidated the mode of action of this combination. In this model, tumor regrowth occurred after remarkable shrinkage by erlotinib; regrowth was successfully inhibited by erlotinib plus bevacizumab. Tumor vascular endothelial growth factor (VEGF) was greatly reduced by erlotinib in the erlotinib-sensitive phase but significantly increased in the erlotinib-refractory phase despite continued treatment with erlotinib. Although EGFR phosphorylation remained suppressed in the erlotinib-refractory phase, phosphorylated extracellular signal-regulated kinase (pERK), phosphorylated AKT, and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) were markedly higher than in the erlotinib-sensitive phase; among these, pERK was suppressed by erlotinib plus bevacizumab. MVD was decreased significantly more with erlotinib plus bevacizumab than with each drug alone. In conclusion, the erlotinib plus bevacizumab combination demonstrated promising efficacy in the B901L xenograft model of EGFR Mut⁺ NSCLC. Re-induction of VEGF and subsequent direct or indirect VEGF-dependent tumor growth was suggested as a major mechanism of erlotinib resistance, and erlotinib plus bevacizumab achieved remarkably prolonged antitumor activity in this model.

Changes in the coelomic microclimate during carbon dioxide laparoscopy: morphological and functional implications

In this article the adverse effects of laparoscopic CO2 pneumoperitoneum and coelomic climate change, and their potential prevention by warmed, humidified carbon dioxide insufflation are reviewed. The use of pressurized cold, dry carbon dioxide (C02) pneumoperitoneum causes a number of local effects on the peritoneal mesothelium, as well as systemic effects. These can be observed at a macroscopic, microscopic, cellular and metabolic level. Local effects include evaporative cooling, oxidative stress, desiccation of mesothelium, disruption of mesothelial cell junctions and glycocalyx, diminished scavenging of reactive oxygen species, decreased peritoneal blood flow, peritoneal acidosis, peritoneal hypoxia or necrosis, exposure of the basal lamina and extracellular matrix, lymphocyte infiltration, and generation of peritoneal cytokines such as IL-1, IL-6, IL-8 and TNFα. Such damage is increased by high CO2 insufflation pressures and gas velocities and prolonged laparoscopic procedures. The resulting disruption of the glycocalyx, mesothelial cell barrier and exposure of the extracellular matrix creates a cascade of immunological and pro-inflammatory events and favours tumour cell implantation. Systemic effects include cardiopulmonary and respiratory changes, hypothermia and acidosis. Such coelomic climate change can be prevented by the use of lower insufflation pressures and preconditioned warm humidified CO2. By achieving a more physiological temperature, pressure and humidity, the coelomic microenvironment can be better preserved during pneumoperitoneum. This has the potential clinical benefits of maintaining isothermia and perfusion, reducing postoperative pain, preventing adhesions and inhibiting cancer cell implantation in laparoscopic surgery.

Changes in the coelomic microclimate during carbon dioxide laparoscopy: morphological and functional implications

In this article the adverse effects of laparoscopic CO2 pneumoperitoneum and coelomic climate change, and their potential prevention by warmed, humidified carbon dioxide insufflation are reviewed. The use of pressurized cold, dry carbon dioxide (C02) pneumoperitoneum causes a number of local effects on the peritoneal mesothelium, as well as systemic effects. These can be observed at a macroscopic, microscopic, cellular and metabolic level. Local effects include evaporative cooling, oxidative stress, desiccation of mesothelium, disruption of mesothelial cell junctions and glycocalyx, diminished scavenging of reactive oxygen species, decreased peritoneal blood flow, peritoneal acidosis, peritoneal hypoxia or necrosis, exposure of the basal lamina and extracellular matrix, lymphocyte infiltration, and generation of peritoneal cytokines such as IL-1, IL-6, IL-8 and TNFα. Such damage is increased by high CO2 insufflation pressures and gas velocities and prolonged laparoscopic procedures. The resulting disruption of the glycocalyx, mesothelial cell barrier and exposure of the extracellular matrix creates a cascade of immunological and pro-inflammatory events and favours tumour cell implantation. Systemic effects include cardiopulmonary and respiratory changes, hypothermia and acidosis. Such coelomic climate change can be prevented by the use of lower insufflation pressures and preconditioned warm humidified CO2. By achieving a more physiological temperature, pressure and humidity, the coelomic microenvironment can be better preserved during pneumoperitoneum. This has the potential clinical benefits of maintaining isothermia and perfusion, reducing postoperative pain, preventing adhesions and inhibiting cancer cell implantation in laparoscopic surgery.

MicroRNA-29c functions as a tumor suppressor by targeting VEGFA in lung adenocarcinoma

Background

Lung adenocarcinoma (LAD) is considered to be a highly aggressive disease with heterogeneous prognosis and the molecular mechanisms underlying tumor progression remain elusive. Growing evidence demonstrates that the dysregulation of microRNAs (miRNAs) plays an important role in various tumor processes. The aim of this study is to discover prognostic miRNA and investigate its role involved in progression of LAD.

Methods

Prognosis related miRNA was detected by miRNA microarray using formalin-fixed paraffin-embedded (FFPE) specimens from 87 patients with IIIA-N2 LAD. The cell proliferation was evaluated by Cell Titer 96 AQueous One Solution Cell Proliferation Assay (MTS), and the migration/invasion was evaluated by transwell assay. The bioinformatics methods and luciferase reporter assay were applied to detect the relationship between miRNA and its target. The mRNA and protein levels of miRNA target were determined by quantitative real time polymerase chain reaction (qRT-PCR) analysis, western blot and enzyme-linked immunosorbent assay (ELISA). Changes of angiogenesis induced by miRNA was evaluated by human umbilical vein endothelial cell (HUVEC) tube formation assay. Immunohistochemistry (IHC) analysis was performed in FFPE specimens of patients to evaluate the correlation between miR-29c with microvessel density (MVD) and vascular endothelial growth factor A (VEGFA) expression.

Results

MiR-29c expression downregulation was significantly associated with unfavorable prognosis in IIIA-N2 LAD. MiR-29c inhibited cell proliferation, migration and invasion in cell lines. Integrated analysis revealed that VEGFA was a direct target of miR-29c. MiR-29c reduced the capability of tumor cells to promote HUVEC tube formation. The compromised cell proliferation, migration/invasion and angiogenesis induced by miR-29c mimic transfection were reversed by transfection of VEGFA expression plasmid. Furthermore, the correlation of miR-29c with MVD and VEGFA was confirmed in patients’ samples.

Conclusions

MiR-29c acts as a tumor suppressor by targeting VEGFA and may represent a promising prognostic biomarker as well as a potential therapeutic target for LAD.

Selective reversal of BCRP-mediated MDR by VEGFR-2 inhibitor ZM323881

The expression of breast cancer resistant protein (BCRP) in lung cancer is correlated with development of multidrug resistance (MDR) and therefore leads to lower response to chemotherapy. ZM323881, a previously developed selective VEGFR-2 inhibitor, was found to have inhibitory effects on BCRP-mediated MDR in this investigation. ZM323881 significantly decreased the cytotoxic doses of mitoxantrone and SN-38 in BCRP-overexpressing NCI-H460/MX20 cells. Mechanistic studies revealed that ZM323881 effected by inhibiting BCRP-mediated drug efflux, leading to intracellular accumulation of BCRP substrates. No significant alteration in the expression levels and localization pattern of BCRP was observed when BCRP-overexpressing cells were exposed to ZM323881. Stimulated bell-shaped ATPase activities were observed. Molecular docking suggested that ZM323881 binds to the modulator site of BCRP and the binding pose is stable validated by 100ns molecular dynamic simulation. Overall, our results indicated that ZM323881 reversed BCRP-related MDR by inhibiting its efflux function. These findings might be useful in developing combination chemotherapy for MDR cancer treatment.

Consensus molecular subtypes and the evolution of precision medicine in colorectal cancer

Critical driver genomic events in colorectal cancer have been shown to affect the response to targeted agents that were initially developed under the 'one gene, one drug' paradigm of precision medicine. Our current knowledge of the complexity of the cancer genome, clonal evolution patterns under treatment pressure and pharmacodynamic effects of target inhibition support the transition from a one gene, one drug approach to a 'multi-gene, multi-drug' model when making therapeutic decisions. Better characterization of the transcriptomic subtypes of colorectal cancer, encompassing tumour, stromal and immune components, has revealed convergent pathway dependencies that mandate a 'multi-molecular' perspective for the development of therapies to treat this disease.