The VEGF signaling pathway in cancer: the road ahead

HSP47 in human diseases: Navigating pathophysiology, diagnosis and therapy

Heat shock protein 47 (HSP47) is a chaperone protein responsible for regulating collagen maturation and transport, directly impacting collagen synthesis levels. Aberrant HSP47 expression or malfunction has been associated with collagen-related disorders, most notably fibrosis. Recent reports have uncovered new functions of HSP47 in various cellular processes. Hsp47 dysregulation in these alternative roles has been linked to various diseases, such as cancer, autoimmune and neurodegenerative disorders, thereby highlighting its potential as both a diagnostic biomarker and a therapeutic target. In this review, we discuss the pathophysiological roles of HSP47 in human diseases, its potential as a diagnostic tool, clinical screening techniques and its role as a target for therapeutic interventions.

The possibility of angiogenesis inhibition in cutaneous melanoma by bevacizumab-loaded lipid-chitosan nanoparticles

Cutaneous malignant melanoma is fastest-growing cancer in white populations with a large majority of dermal cancer death. The activity of vascular endothelial growth factors (VEGFs) results in the signaling of a variety of downstream intracellular pathways that ultimately leads to cell activation, proliferation, migration, and angiogenesis. VEGF inhibitors such as bevacizumab are widely used in chemotherapy with systemic administration, which in many cases is associated with a variety of side effects. Here, we designed and synthesized a lipid-polymer nanoparticle for local administration of bevacizumab. Drug release, dermal absorption, and the effects of synthesized nanoparticles containing bevacizumab on cell proliferation and in vitro and in vivo angiogenesis were investigated. Encapsulating bevacizumab in the synthesized nanoparticles resulted in a significant increase in its dermal absorption compared to free bevacizumab. Also, the suppressor effects of bevacizumab encapsulated in the synthesized nanoparticle on cell proliferation and angiogenesis were significantly more than those of free bevacizumab. Our findings indicate the remarkable effects of lipid-polymer nanoparticles in dermal absorption and in maintaining bevacizumab bioactivity, suggesting therapeutic benefits of local bevacizumab administration for angiogenesis-related disorders such as cutaneous melanoma. Chitosan nanoparticles containing bevacizumab antibody were synthesized by ion exchange method, and finally, these nanoparticles were coated with lipid (Lip-Chi-Bev NPs). In this study, the effect of synthesized nanoparticles on dermal absorption of bevacizumab was evaluated and its potential in inhibiting angiogenesis was evaluated by in vitro and in vivo models.

The Determinative Role of Cytokines in Retinopathy of Prematurity

Retinopathy of prematurity (ROP) is a neonatal disease corresponding to vision impairment and blindness. Utilizing the pathogenesis of ROP and the risk factors affecting its progression can help prevent and reduce its incidence and lead to the emergence and development of new treatment strategies. Factors influencing retinopathy include growth and inflammatory factors that play an essential role in the pathogenesis of the ROP. This review summarizes the most critical factors in the pathogenesis of ROP.

Decoding the mechanism of vascular morphogenesis to explore future prospects in targeted tumor therapy

The growth and formation of blood vessels is an undeniably fundamental biological process crucial to controlling overall development of an organism. This phenomenon consists of two separate processes, commencing with vasculogenesis, which refers to the process of blood vessel formation strictly in embryonic stages, via de novo endothelial cell synthesis. Angiogenesis continues the formation of the vascular network via sprouting and splitting. Tumor growth is dependent on the growth and supply of blood vessels around the tumor mass. Extracellular matrix (ECM) molecules can promote angiogenesis by establishing a vascular network and sequestering pro-angiogenic growth factors. Although the methods by which tumor-associated fibroblasts (which differ in phenotype from normal fibroblasts) influence angiogenesis are unknown, they are thought to be a major source of growth factors and cytokines that attract endothelial cells. Chemokines and growth factors (sourced from macrophages and neutrophils) are also regulators of angiogenesis. When considered as a whole, the tumor microenvironment is a heterogenous and dynamic mass of tissue, composed of a plethora of cell types and an ECM that can fundamentally control the pathological angiogenic switch. Angiogenesis is involved in numerous diseases, and understanding the various mechanisms surrounding this phenomenon is key to finding cures.

Histone Deacetylase Inhibitor I3 Induces the Differentiation of Acute Myeloid Leukemia Cells with t (8; 21) or MLL Gene Translocation and Leukemic Stem-Like Cells

Acute myeloid leukemia (AML) is a heterogeneous disorder characterized by the clonal expansion and differentiation arrest of leukemic cells in peripheral blood and bone marrow. Though the treatment using cytarabine-based protocol for AML patients with t (8; 21) translocation has improved the 5-year overall survival rate, drug resistance continues to be the principal limiting factor for the cure of the disease. In addition, very few AML patients with mixed lineage leukemia gene rearrangements (MLLr) have a desirable outcome. This study evaluated the cell differentiation effect of a potent HDAC (histone deacetylase) inhibitor, I3, and its possible mechanism on the AML cells with t (8; 21) translocation or MLLr and leukemic stem-like cells (Kasumi-1, KG-1, MOLM-13, and THP-1). I3 exhibited efficient anti-proliferative activity on these cells via promoting cell differentiation, accompanied by the cell cycle exit at G0/G1. Importantly, I3 showed the properties of HDAC inhibition, as assessed by the acetylation of histones H3 and H4, which resulted in blocking the activation of the VEGF (vascular endothelial growth factor)-MAPK (mitogen-activated protein kinase) signaling pathway in the Kasumi-1 cell line. These data demonstrate that I3 could be a potent chromatin-remodeling agent to surmount the differentiation block in AML patients, including those with t (8; 21) translocation or MLLr, and could be a potent and selective agent for AML treatment.

Network pharmacology-based study to identify the significant pathways of Lentinula edodes against cancer

Lentinula edodes (LE) is known as a good food source with potent anticancer efficacy, but its active chemical compounds and pathways against cancer have not been revealed. This study was to uncover the active chemical constituents and pathways of LE against cancer through network pharmacology. The chemical compositions were recognized by gas chromatography-mass spectrometry (GC-MS) and filtered drug-like compounds (DLCs) by SwissADME. Targets related to filtered compounds were recognized by two public databases and the final overlapping targets were identified by Venn diagram. Then, protein-protein interaction (PPI) and pathway-target-compound (PTC) networks were built by RStudio. Ultimately, we recognized the key compounds and targets via molecular docking test (MDT). A total of 33 compounds from LE were accepted by Lipinski's rule were selected as DLCs. The 33 compounds were associated with 108 targets and a key target (cyclooxygenase2 [COX2]) was identified through PPI networks. Most significantly, inactivation of pathways in cancer and activation of peroxisome proliferator activated receptor signaling pathway were significant pathways of LE. On MDT, we identified a key compound (Indole, 2-methyl-3-phenyl) on COX2 related to inactivation of athways in cancer, additionally, the number of 6 ergostane steroids was associated with the two pathways might be dual efficacy to alleviate inflammation against cancer. Overall, 13 targets, 11 compounds, and 2 key pathways of LE were identified as the significant elements to treat cancer. Hence, this study shows therapeutic evidence to verify the promising clinical effect of LE on cancer, suggesting that LE might be an important mushroom against cancer. PRACTICAL APPLICATIONS: Lentinula edodes (LE) has been used widely in cuisine as well as alternative medicines, especially, for anticancer. The LE has rich nutritional compounds including proteins, vitamins, polyphenols, and glucans, however, most of which have a critical hurdle as poor bioavailability not to be applicable for pharmaceuticals. Its main cause is very hydrophilic property. Thus, we adopted GC-MS analysis to identify lipophilic compounds to enhance cell permeability involved in bioavailability. The compounds selected from LE were confirmed by Lipinski's rule for drug-like-compounds (DLCs). Then, we retrieved targets associated with DLCs, and multiple pathways, multiple targets, and multiple compounds against cancer on network-based analysis. In summary, our study reveals the medicinal value of LE on cancer based on the multicomponents. Overall, the aim of this work is to represent the pharmacological evidence to reveal the therapeutic efficacy of AC on cancer, suggesting that DLCs from AC might be alleviators to dampen cancer.

Identification of key tumor stroma-associated transcriptional signatures correlated with survival prognosis and tumor progression in breast cancer

BACKGROUND

The aberrant expression of stromal gene signatures in breast cancer has been widely studied. However, the association of stromal gene signatures with tumor immunity, progression, and clinical outcomes remains lacking.

METHODS

Based on eight breast tumor stroma (BTS) transcriptomics datasets, we identified differentially expressed genes (DEGs) between BTS and normal breast stroma. Based on the DEGs, we identified dysregulated pathways and prognostic hub genes, hub oncogenes, hub protein kinases, and other key marker genes associated with breast cancer. Moreover, we compared the enrichment levels of stromal and immune signatures between breast cancer patients with bad and good clinical outcomes. We also investigated the association between tumor stroma-related genes and breast cancer progression.

RESULTS

The DEGs included 782 upregulated and 276 downregulated genes in BTS versus normal breast stroma. The pathways significantly associated with the DEGs included cytokine-cytokine receptor interaction, chemokine signaling, T cell receptor signaling, cell adhesion molecules, focal adhesion, and extracellular matrix-receptor interaction. Protein-protein interaction network analysis identified the stromal hub genes with prognostic value in breast cancer, including two oncogenes (COL1A1 and IL21R), two protein kinases encoding genes (PRKACA and CSK), and a growth factor encoding gene (PLAU). Moreover, we observed that the patients with bad clinical outcomes were less enriched in stromal and antitumor immune signatures (CD8 + T cells and tumor-infiltrating lymphocytes) but more enriched in tumor cells and immunosuppressive signatures (MDSCs and CD4 + regulatory T cells) compared with the patients with good clinical outcomes. The ratios of CD8 + /CD4 + regulatory T cells were lower in the patients with bad clinical outcomes. Furthermore, we identified the tumor stroma-related genes, including MCM4, SPECC1, IMPA2, and AGO2, which were gradually upregulated through grade I, II, and III breast cancers. In contrast, COL14A1, ESR1, SLIT2, IGF1, CH25H, PRR5L, ABCA6, CEP126, IGDCC4, LHFP, MFAP3, PCSK5, RAB37, RBMS3, SETBP1, and TSPAN11 were gradually downregulated through grade I, II, and III breast cancers. It suggests that the expression of these stromal genes has an association with the progression of breast cancers. These progression-associated genes also displayed an expression association with recurrence-free survival in breast cancer patients.

CONCLUSIONS

This study identified tumor stroma-associated biomarkers correlated with deregulated pathways, tumor immunity, tumor progression, and clinical outcomes in breast cancer. Our findings provide new insights into the pathogenesis of breast cancer.

Receptor tyrosine kinases as a therapeutic target by natural compounds in cancer treatment

Background

Receptor tyrosine kinases (RTKs) are single-pass transmembrane proteins that play significant roles in regulating cellular processes, including cell division and growth. Overexpression and mutations of RTKs have been found in clinical manifestations of different forms of cancer. Therefore, RTKs have received considerable interest as a therapeutic biomarker in the treatment of cancer cells.

Main body of the abstract

Comprehensive data on RTKs, pharmacological and biological properties of natural compounds were systematically searched up to 2021 using relevant keywords from various databases, such as Google Scholar, PubMed, Web of Science, and Scopus. The scientific search by various standard electronic resources and databases unveils the effectiveness of medicinal plants in the treatment of various cancers. In vitro and in vivo studies suggested that bioactive compounds such as flavonoids, phenols, alkaloids, and many others can be used pharmacologically as RTKs inhibitors (RTKI) either by competing with ATP at the ATP binding site of the tyrosine kinase domain or competing for the receptor extracellular domain. Additionally, studies conducted on animal models indicated that inhibition of RTKs catalytic activity by natural compounds is one of the most effective ways to block the activation of RTKs signaling cascades, thereby hampering the proliferation of cancer cells. Furthermore, various pharmacological experiments, transcriptomic, and proteomic data also reported that cancer cells treated with different plants extracts or isolated phytochemicals exhibited better anticancer properties with minimal side effects than synthetic drugs. Clinically, natural compounds have demonstrated significant anti-proliferative effect via induction of cell apoptosis in cancer cell lines.

Short conclusion

An in-depth knowledge of the mechanism of inhibition and structural characterization of RTKs is important to the design of novel and selective RTKIs. This review focuses on the molecular mechanisms and structures of natural compounds RTKI targeting vascular endothelial growth factor, epidermal growth factor receptor, insulin receptor, and platelet-derived growth factor while also giving future directions to ameliorate the scientific burden of cancer.

Graphic abstract

Improving Outcomes of Tyrosine Kinase Inhibitors in Hepatocellular Carcinoma: New Data and Ongoing Trials

Targeted therapies such as oral tyrosine kinase inhibitors (TKIs) are the main therapeutic strategy effective for advanced hepatocellular carcinoma (HCC). Currently six tyrosine kinase inhibitors for HCC therapy have been approved. The newly approved first-line drug donafenib represent the major milestones in HCC therapeutics in recent years. However, drug resistance in HCC remains challenging due to random mutations in target receptors as well as downstream pathways. TKIs-based combinatorial therapies with immune checkpoint inhibitors such as PD-1/PD-L1 antibodies afford a promising strategy to further clinical application. Recent developments of nanoparticle-based TKI delivery techniques improve drug absorption and bioavailability, enhance efficient targeting delivery, prolonged circulation time, and reduce harmful side effects on normal tissues, which may improve the therapeutic efficacy of the TKIs. In this review, we summarize the milestones and recent progress in clinical trials of TKIs for HCC therapy. We also provide an overview of the novel nanoparticle-based TKI delivery techniques that enable efficient therapy.

3D tumor angiogenesis models: recent advances and challenges

The development of blood vessels, referred to as angiogenesis, is an intricate process regulated spatially and temporally through a delicate balance between the qualitative and quantitative expression of pro and anti-angiogenic molecules. As angiogenesis is a prerequisite for solid tumors to grow and metastasize, a variety of tumor angiogenesis models have been formulated to better understand the underlying mechanisms and associated clinical applications. Studies have demonstrated independent mechanisms inducing angiogenesis in tumors such as (a) HIF-1/VEGF mediated paracrine interactions between a cancer cell and endothelial cells, (b) recruitment of progenitor endothelial cells, and (c) vasculogenic mimicry. Moreover, single-cell sequencing technologies have indicated endothelial cell heterogeneity among organ systems including tumor tissues. However, existing angiogenesis models often rely upon normal endothelial cells which significantly differ from tumor endothelial cells exhibiting distinct (epi)genetic and metabolic signatures. Besides, the existence of intra-individual variations necessitates the development of improved tumor vascular model systems for personalized medicine. In the present review, we summarize recent advancements of 3D tumor vascular model systems which include (a) tissue engineering-based tumor models; (b) vascular organoid models, and (c) organ-on-chips and their importance in replicating the tumor angiogenesis along with the associated challenges to design improved models.

Evaluation of biomarkers, genetic mutations, and epigenetic modifications in early diagnosis of pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) is one of the deadliest malignancies with an alarming mortality rate. Despite significant advancement in diagnostics and therapeutics, early diagnosis remains elusive causing poor prognosis, marred by mutations and epigenetic modifications in key genes which contribute to disease progression.

AIM

To evaluate the various biological tumor markers collectively for early diagnosis which could act as prognostic biomarkers and helps in future therapeutics of PC in Kashmir valley.

METHODS

A total of 50 confirmed PC cases were included in the study to evaluate the levels of carbohydrate antigen 19-9 (CA 19-9), tissue polypeptide specific antigen (TPS), carcinoembryonic antigen (CEA), vascular endothelial growth factor-A (VEGF-A), and epidermal growth factor receptor (EGFR). Mutational analysis was performed to evaluate the mutations in Kirsten rat sarcoma (KRAS), Breast cancer type 2 (BRCA-2), and deleted in pancreatic cancer-4 (DPC-4) genes. However, epigenetic modifications (methylation of CpG islands) were performed in the promoter regions of cyclin-dependent kinase inhibitor 2A (p16; CDKN2A), MutL homolog 1 (hMLH1), and Ras association domain-containing protein 1(RASSF1A) genes.

RESULTS

We found significantly elevated levels of biological markers CA 19-9 (P ≤ 0.05), TPS (P ≤ 0.05), CEA (P ≤ 0.001), and VEGF (P ≤ 0.001). Molecular genetic analysis revealed that KRAS gene mutation is predominant in codon 12 (16 subjects, P ≤ 0.05), and 13 (12 subjects, P ≤ 0.05). However, we did not find a mutation in DPC-4 (1203G > T) and BRCA-2 (617delT) genes. Furthermore, epigenetic modification revealed that CpG methylation in 21 (P ≤ 0.05) and 4 subjects in the promoter regions of the p16 and hMLH1 gene, respectively.

CONCLUSION

In conclusion, CA 19-9, TPS, CEA, and VEGF levels were significantly elevated and collectively have potential as diagnostic and prognostic markers in PC. Global data of mutation in the KRAS gene commonly in codon 12 and rare in codon 13 could augment the predisposition towards PC. Additionally, methylation of the p16 gene could also modulate transcription of genes thereby increasing the predisposition and susceptibility towards PC.

Mucin in cancer: a stealth cloak for cancer cells

Mucins are high molecular-weight epithelial glycoproteins and are implicated in many physiological processes, including epithelial cell protection, signaling transduction, and tissue homeostasis. Abnormality of mucus expression and structure contributes to biological properties related to human cancer progression. Tumor growth sites induce inhospitable conditions. Many kinds of research suggest that mucins provide a microenvironment to avoid hypoxia, acidic, and other biological conditions that promote cancer progression. Given that the mucus layer captures growth factors or cytokines, we propose that mucin helps to ameliorate inhospitable conditions in tumor-growing sites. Additionally, the composition and structure of mucins enable them to mimic the surface of normal epithelial cells, allowing tumor cells to escape from immune surveillance. Indeed, human cancers such as mucinous carcinoma, show a higher incidence of invasion to adjacent organs and lymph node metastasis than do non-mucinous carcinoma. In this mini-review, we discuss how mucin provides a tumor-friendly environment and contributes to increased cancer malignancy in mucinous carcinoma.

Landscape of Current Targeted Therapies for Advanced Colorectal Cancer

Colorectal cancer (CRC) is one of the most frequent and lethal cancer types worldwide. While surgery with chemotherapy and radiotherapy remains the only curative approach for localized CRC, for metastatic disease the therapeutic landscape has significantly evolved over the last years. Development and approval of novel targeted therapies, such as monoclonal antibodies against EGFR and VEGF, have significantly increased the median survival of patients with metastatic disease, with some trials reporting a benefit over 40 months. Increasing accessibility of high throughput sequencing has unraveled several new therapeutic targets. Actionable alterations, such as HER2 overexpression, BRAF mutations, and NTRK fusions, are currently available in metastatic disease, providing significant therapeutic opportunities for these patients, while new emerging agents, as immune checkpoint inhibitors, promise better treatment options in the near future. In this chapter, an overview of established and future CRC targeted therapies in the clinical setting is provided, as well as their mechanism of action, limitations, and future applicability.

Interleukins and cytokine biomarkers in uveitis

Interleukins and cytokines are involved in the pathogenesis of uveitis of heterogeneous origin. Understanding the basics of the ocular immune privilege is a fulcrum to discern their specific role in diverse uveitis to potentially translate as therapeutic targets. This review attempts to cover these elements in uveitis of infectious, noninfectious and masquerade origin. Insights of the molecular targets in novel therapy along with the vision of future research are intriguing.

Nanotechnology to the Rescue: Treatment Perspective for the Immune Dysregulation Observed in COVID-19

The study of the use of nanotechnology for drug delivery has been extensive. Nanomedical approaches for therapeutics; drug delivery in particular is superior to conventional methods in that it allows for controlled targeted delivery and release, higher stability, extended circulation time, minimal side-effects, and improved pharmacokinetic clearance (of the drug) form the body, to name a few. The magnitude of COVID-19, the current ongoing pandemic has been severe; it has caused widespread the loss of human life. In individuals with severe COVID-19, immune dysregulation and a rampant state of hyperinflammation is observed. This kind of an immunopathological response is detrimental and results in rapid disease progression, development of secondary infections, sepsis and can be fatal. Several studies have pin-pointed the reason for this immune dysregulation; deviations in the signaling pathways involved in the mediation and control of immune responses. In severe COVID-19 patients, many signaling cascades including JAK/STAT, NF-κB, MAPK/ERK, TGF beta, VEGF, and Notch signaling were found to be either upregulated or inactivated. Targeting these aberrant signaling pathways in conjunction with antiviral therapy will effectuate mitigation of the hyperinflammation, hypercytokinemia, and promote faster recovery. The science of the use of nanocarriers as delivery agents to modulate these signaling pathways is not new; it has already been explored for other inflammatory diseases and in particular, cancer therapy. Numerous studies have evaluated the efficacy and potential of nanomedical approaches to modulate these signaling pathways and have been met with positive results. A treatment regime, that includes nanotherapeutics and antiviral therapies will prove effective and holds great promise for the successful treatment of COVID-19. In this article, we review different nanomedical approaches already studied for targeting aberrant signaling pathways, the host immune response to SARS-CoV-2, immunopathology and the dysregulated signaling pathways observed in severe COVID-19 and the current treatment methods in use for targeting signaling cascades in COVID-19. We then conclude by suggesting that the use of nanomedical drug delivery systems for targeting signaling pathways can be extended to effectively target the aberrant signaling pathways in COVID-19 for best treatment results.

A Novel 85-Gene Expression Signature Predicts Unfavorable Prognosis in Acute Myeloid Leukemia

Aim:

Acute myeloid leukemia (AML) is a heterogeneous disorder with complex genetic basis and adverse prognosis. Cytogenetics risk, somatic mutations and gene expression profiles are important prognostic factors for AML patients. However, accurate stratification of patient prognosis remains an unsolved problem in AML. This study was to to develop a novel gene profile to accurately classify AML patients into subgroups with different survival probabilities.

Methods:

Survival-related genes were determined by Kaplan–Meier survival analysis and multivariate analysis using the expression and clinical data of 405 AML patients from Oregon Health & Science University (OHSU) dataset and validated in The Cancer Genome Atlas (TCGA) database. Feature selection was performed by using the Least Absolute Shrinkage and Selection Operator (LASSO) method. With the LASSO model, a prognostic 85-gene score was established and compared with 2 known gene-expression risk scores. The stratification of AML patients was performed by unsupervised hierarchical clustering of 85 gene expression levels to identify clusters of AML patients with different survival probabilities.

Results:

The LASSO model comprising 85 genes was considered as the optimal model based on relatively high area under curve value (0.83) and the minimum mean squared error. The 85-gene score was associated with increased mortality in AML patients. Hierarchical clustering analysis of the 85 genes revealed 3 subgroups of AML patients in the OHSU dataset. The cluster1 AML patients were associated with more female cases, higher percent of bone marrow blast cells, 85-gene score, cytogenetics risk, more frequent FLT3-ITD, DNMT3A, NP1 mutations, less frequent TP53, RUNX1 mutations, poorer overall survival than cluster2 tumors. The 85-gene score had higher AUC (0.75) than the 5-gene risk score and LSC17 score (0.74 and 0.65).

Conclusions:

The 85-gene score is superior to the 2 established prognostic gene signatures in the prediction of prognosis of AML patients.

Recent Advances in Monoclonal Antibody Therapy for Colorectal Cancers

Colorectal cancer (CRC) is one of the leading causes of cancer deaths worldwide. Recent advances in recombinant DNA technology have led to the development of numerous therapeutic antibodies as major sources of blockbuster drugs for CRC therapy. Simultaneously, increasing numbers of therapeutic targets in CRC have been identified. In this review, we first highlight the physiological and pathophysiological roles and signaling mechanisms of currently known and emerging therapeutic targets, including growth factors and their receptors as well as immune checkpoint proteins, in CRC. Additionally, we discuss the current status of monoclonal antibodies in clinical development and approved by US Food and Drug Administration for CRC therapy.

Characterization of pathways involved in colorectal cancer using real-time RT-PCR gene expression data

AIM

Efforts to explore biomarkers and biological pathways involved in the disease are needed to improve colorectal cancer (CRC) diagnosis and alternative treatments.

BACKGROUND

The fourth common malignancy in the world is colorectal cancer. The over-all burden is predicted to rise by 2030.

METHODS

In the current study, nine genes were selected. Previously, a panel of genes by Agendia, a classifier of robust gene expression (ColoPrint), was determined to significantly improve the prognostic accuracy of pathologic factors in stage II and III colorectal cancer patients. Five genes, including Ppara, Mctp1, Pyroxd1, Il2r, and Cyfip2, from this panel and four other genes which were not in this panel but were cited abundantly in the literature were selected. Then, expression levels of the selected genes in CRC tissue were compared with levels in adjacent normal tissue. To identify the pathways involved in CRC, gene set enrichment analysis was subsequently performed. Furthermore, to illustrate the relationship between genes in this disease, the cross-shaped co-expression pattern and gene regulatory network were determined using computational methods.

RESULTS

This research found that the pairs of genes: {IL2R, CYFIP2}, {FOXM1, PPARA}, {MCTP1, CTSC}, and {PYROXD1, CYF1P2} are functionally related. Furthermore, two differentially expressed gene pairs ({FOXM1, PPARA} and {IL2R, CYFIP2}) are involved in the vascular endothelial growth factor receptor signaling pathway and the purine ribonucleoside diphosphate metabolic process, respectively.

CONCLUSION

This research found that the combination of computational analysis and laboratory data provided the opportunity to better characterize the relation between central colorectal cancer genes as well as possible pathways involved in the colorectal cancer.

Compounds from Natural Sources as Protein Kinase Inhibitors

The advantage of natural compounds is their lower number of side-effects when compared to most synthetic substances. Therefore, over the past several decades, the interest in naturally occurring compounds is increasing in the search for new potent drugs. Natural compounds are playing an important role as a starting point when developing new selective compounds against different diseases. Protein kinases play a huge role in several diseases, like cancers, neurodegenerative diseases, microbial infections, or inflammations. In this review, we give a comprehensive view of natural compounds, which are/were the parent compounds in the development of more potent substances using computational analysis and SAR studies.

DKK2 blockage-mediated immunotherapy enhances anti-angiogenic therapy of Kras mutated colorectal cancer

There are limited options for targeted therapies for colorectal cancer (CRC). Anti-EGFR therapy is limited to CRC without KRAS mutations. Even worse, most of CRC are refractory to currently immune checkpoint blockade. DKK2, which is upregulated in CRC, was recently found to suppress host immune responses, and its blockage effectively impeded tumor progression in benign genetic CRC models in our previous study. Here, our recent study demonstrated that in human CRC tumor samples expressing high levels of DKK2, DKK2 blockade caused stronger activation of tumor infiltrating CD8⁺ T cells in ex vivo culture. Intriguingly, we observed a correlation of high DKK2 expression with increased lymph node metastasis prevalence in these CRC patients as well. Furthermore, in a mouse genetic CRC model with mutations in APC and KRAS, which more closely mimics advanced human CRC, we confirmed the tumor inhibitory effect of DKK2 blockade, which significantly retarded tumor progression and extended survival, with increased immune effector cell activation and reduced angiogenesis. Based on this, we performed a combined administration of DKK2 blockade with sub-optimal anti-VEGFR treatment and observed a synergetic effect on suppressing tumor angiogenesis and progression, as well as extending survival, better than those of every single therapy. Thus, this study provides further evidence for the potential therapeutic application of DKK2 blockade in the clinical treatment of human CRC.

Comprehensive gene and pathway analysis of cervical cancer progression

Cervical Cancer is one of the leading causes of cancer-associated mortality in women. The present study aimed to identify key genes and pathways involved in cervical cancer (CC) progression, via a comprehensive bioinformatics analysis. The GSE63514 dataset from the Gene Expression Omnibus database was analyzed for hub genes and cancer progression was divided into four phases (phases I-IV). Pathway enrichment, protein-protein interaction (PPI) and pathway crosstalk analyses were performed, to identify key genes and pathways using a criterion nodal degree ≥5. Gene pathway analysis was determined by mapping the key genes into the key pathways. Co-expression between key genes and their effect on overall survival (OS) time was assessed using The Cancer Genome Atlas database. A total of 3,446 differentially expressed genes with 107 hub genes were identified within the four phases. A total of 14 key genes with 11 key pathways were obtained, following extraction of ≥5 degree nodes from the PPI and pathway crosstalk networks. Gene pathway analysis revealed that CDK1 and CCNB1 regulated the cell cycle and were activated in phase I. Notably, the following terms, 'pathways in cancer', 'focal adhesion' and the 'PI3K-Akt signaling pathway' ranked the highest in phases II-IV. Furthermore, FN1, ITGB1 and MMP9 may be associated with metastasis of tumor cells. STAT1 was indicated to predominantly function at the phase IV via cancer-associated signaling pathways, including 'pathways in cancer' and 'Toll-like receptor signaling pathway'. Survival analysis revealed that high ITGB1 and FN1 expression levels resulted in significantly worse OS. CDK1 and CCNB1 were revealed to regulate proliferation and differentiation through the cell cycle and viral tumorigenesis, while FN1 and ITGB1, which may be developed as novel prognostic factors, were co-expressed to induce metastasis via cancer-associated signaling pathways, including PI3K-Art signaling pathway, and focal adhesion in CC; however, the underlying molecular mechanisms require further research.

Endothelial Cells (ECs) Metabolism: A Valuable Piece to Disentangle Cancer Biology

Effective therapies to fight cancer should not be focused specifically on cancer cells, but it should consider the various components of the TME. Non-cancerous cells cooperate with cancer cells by sharing signaling and organic molecules, accounting for cancer progression. Most of the anti-angiogenic therapy clinically approved for the treatment of human diseases relies on targeting vascular endothelial growth factor (VEGF) signaling pathway. Unexpectedly and unfortunately, the results of anti-angiogenic therapies in the treatment of human diseases are not so effective, showing an insufficient efficacy and resistance.This chapter will give some insights on showing that targeting endothelial cell metabolism is a missing piece to revolutionize cancer therapy. Only recently endothelial cell (EC) metabolism has been granted as an important inducer of angiogenesis. Metabolic studies in EC demonstrated that targeting EC metabolism can be an alternative to overcome the failure of anti-angiogenic therapies. Hence, it is urgent to increase the knowledge on how ECs alter their metabolism during human diseases, in order to open new therapeutic perspectives in the treatment of pathophysiological angiogenesis, as in cancer.

Network Pharmacology Approach Reveals the Potential Immune Function Activation and Tumor Cell Apoptosis Promotion of Xia Qi Decoction in Lung Cancer

As the leading cause of cancer death worldwide, lung cancer (LC) has seriously affected human health and longevity. Chinese medicine is a complex system guided by traditional Chinese medicine theories (TCM). Nowadays, the clinical application of TCM for LC patients has become the focus for its effectiveness and security. In this paper, we will analyze and study the mechanism of Xia Qi Decoction (XQD) in the treatment of LC. The results collectively show that XQD could act on 41 therapeutic targets of LC. At the same time, 8 of 41 targets were significantly expressed in immune tissues and cells by activating CD8+T cells to promote apoptosis of cancer cells. It reveals the molecular mechanism of XQD in the treatment of LC from the perspective of network pharmacology. In addition, in the treatment of LC, XQD can activate (up-regulate) the function of immune cells, promote the apoptosis of tumor cells, and have an active anti-tumor immune effect. In conclusion, this study reveals the unique advantages of traditional Chinese medicine in the treatment of cancer, in reinforcing the healthy qi and eliminating the pathogenic factors. More research, however, is needed to verify the potential mechanisms.

Successful management of cutaneous lymphangitis carcinomatosa arising from cervical cancer with paclitaxel-cisplatin and bevacizumab combination therapy: a case report and review of the literature

Background

Globally, cervical cancer is the fourth most common cancer in women. Here, we report a case of cutaneous lymphangitis carcinomatosa arising from cervical cancer, an extremely rare and treatment-resistant condition.

Case presentation

A 64-year-old Japanese woman presented with genital bleeding. She was diagnosed as having stage IB1 squamous cell cervical cancer and subsequently treated with radiotherapy. Approximately 2 years after the curative radiotherapy, she developed itching, skin rash, and small nodules on her left femoral and pubic area. Slight ¹⁸F-fluorodeoxyglucose uptake was detected at her left femoral skin on positron emission tomography with computed tomography. A histopathological examination was performed on a biopsy sample from an erythematous macule on her left femoral skin and vulva. Consequently, she was diagnosed as having cutaneous lymphangitis carcinomatosa arising from cervical cancer. Paclitaxel (135 mg/m²), cisplatin (50 mg/m²), and bevacizumab (15 mg/kg) combination therapy was administered every 21 days. Both itching and rash improved after three treatment cycles. After the completion of six cycles, skin erythema in the femoral and vulval area disappeared completely. Our patient experienced a 25-month symptom-free interval after the last chemotherapy session.

Conclusion

Our findings suggest that combination chemotherapy plus bevacizumab is an effective therapeutic option in patients with cutaneous lymphangitis carcinomatosa arising from cervical cancer.

The Microenvironment of Pituitary Tumors-Biological and Therapeutic Implications

The tumor microenvironment (TME) includes resident and infiltrative non-tumor cells, as well as blood and lymph vessels, extracellular matrix molecules, and numerous soluble factors, such as cytokines and chemokines. While the TME is now considered to be a prognostic tool and a therapeutic target for many cancers, little is known about its composition in pituitary tumors. This review summarizes our current knowledge of the TME within pituitary tumors and the strong interest in TME as a therapeutic target. While we cover the importance of angiogenesis and immune infiltrating cells, we also address the role of the elusive folliculostellate cells, the emerging literature on pituitary tumor-associated fibroblasts, and the contribution of extracellular matrix components in these tumors. The cases of human pituitary tumors treated with TME-targeting therapies are reviewed and emerging concepts of vascular normalization and combined therapies are presented. Together, this snapshot overview of the current literature pinpoints not only the underestimated role of TME components in pituitary tumor biology, but also the major promise it may offer for both prognosis and targeted therapeutics.

pathfindR: An R Package for Comprehensive Identification of Enriched Pathways in Omics Data Through Active Subnetworks

Pathway analysis is often the first choice for studying the mechanisms underlying a phenotype. However, conventional methods for pathway analysis do not take into account complex protein-protein interaction information, resulting in incomplete conclusions. Previously, numerous approaches that utilize protein-protein interaction information to enhance pathway analysis yielded superior results compared to conventional methods. Hereby, we present pathfindR, another approach exploiting protein-protein interaction information and the first R package for active-subnetwork-oriented pathway enrichment analyses for class comparison omics experiments. Using the list of genes obtained from an omics experiment comparing two groups of samples, pathfindR identifies active subnetworks in a protein-protein interaction network. It then performs pathway enrichment analyses on these identified subnetworks. To further reduce the complexity, it provides functionality for clustering the resulting pathways. Moreover, through a scoring function, the overall activity of each pathway in each sample can be estimated. We illustrate the capabilities of our pathway analysis method on three gene expression datasets and compare our results with those obtained from three popular pathway analysis tools. The results demonstrate that literature-supported disease-related pathways ranked higher in our approach compared to the others. Moreover, pathfindR identified additional pathways relevant to the conditions that were not identified by other tools, including pathways named after the conditions.

lncRNA ROR promotes the progression of renal cell carcinoma through the miR‑206/VEGF axis

Renal cell carcinoma (RCC) is the most common kidney malignancy, responsible for ~80% of all cases in adults. The pathogenesis of RCC is complex, involving alterations at both the genetic and epigenetic levels. Numerous signaling pathways, such as PI3K/Akt/mTOR and Wnt‑β‑catenin have been demonstrated to be associated with the tumorigenesis and development of RCC. Long non‑coding RNAs (lncRNAs) are functional RNA molecules involved in the initiation and progression of cancer, and investigating the effects of lncRNA could facilitate the development of novel treatments. The lncRNA regulator of reprogramming (ROR) is aberrantly expressed in a variety of tumors. However, its underlying mechanisms remain largely unknown. In the present study, ROR was found to be upregulated and microRNA (miR)‑206 was found to be downregulated in RCC tissues and cells. Furthermore, the knockdown of ROR inhibited the proliferation, migration and invasion of RCC cells. It was found that ROR binds to miR‑206, and that ROR‑induced cell proliferation and metastasis were reversed by the overexpression of miR‑206. In addition, the levels of miR‑206 and ROR were negatively correlated in RCC tissues. Furthermore, the overexpression of miR‑206 notably suppressed the proliferation, migration and invasion of RCC cells, and these effects were enhanced by the knockdown of vascular endothelial growth factor (VEGF); cell growth and metastasis induced by miR‑206 inhibitors could be reversed by the knockdown of VEGF. In addition, the expression levels of miR‑206 and VEGF were inversely correlated in RCC samples. In summary, the results of the present study revealed that ROR was upregulated in RCC tissues, which promoted tumor progression by regulating the miR‑206/VEGF axis. The present findings provided a novel insight into the potential functions of ROR in RCC, and the ROR/miR‑206/VEGF pathway may be a promising therapeutic target for the treatment of patients with RCC.

Stoichioproteomics reveal oxygen usage bias, key proteins and pathways in glioma

Background

The five-year survival rate and therapeutic effect of malignant glioma is low. Identification of key/associated proteins and pathways in glioma is necessary for developing effective diagnosis and targeted therapy of glioma. In addition, Glioma involves hypoxia-specific microenvironment, whether hypoxia restriction influences the stoichioproteomic characteristics of expressed proteins is unknown.

Methods

In this study, we analyzed the most comprehensive immunohistochemical data from 12 human glioma samples and 4 normal cell types of cerebral cortex, identified differentially expressed proteins (DEPs), and researched the oxygen contents of DEPs, highly and lowly expressed proteins. Further we located key genes on human genome to determine their locations and enriched them for key functional pathways.

Results

Our results showed that although no difference was detected on whole proteome, the average oxygen content of highly expressed proteins is 6.65% higher than that of lowly expressed proteins in glioma. A total of 1480 differentially expressed proteins were identified in glioma, including 226 up regulated proteins and 1254 down regulated proteins. The average oxygen content of up regulated proteins is 2.56% higher than that of down regulated proteins in glioma. The localization of differentially expressed genes on human genome showed that most genes were on chromosome 1 and least on Y. The up regulated proteins were significantly enriched in pathways including cell cycle, pathways in cancer, oocyte meiosis, DNA replication etc. Functional dissection of the up regulated proteins with high oxygen contents showed that 51.28% of the proteins were involved in cell cycle and cyclins.

Conclusions

Element signature of oxygen limitation could not be detected in glioma, just as what happened in plants and microbes. Unsaved use of oxygen by the highly expressed proteins and DEPs were adapted to the fast division of glioma cells. This study can help to reveal the molecular mechanism of glioma, and provide a new approach for studies of cancer-related biomacromolecules. In addition, this study lays a foundation for application of stoichioproteomics in precision medicine.

Electronic supplementary material

The online version of this article (10.1186/s12920-019-0571-y) contains supplementary material, which is available to authorized users.

Circulating miR-182-5p and miR-5187-5p as biomarkers for the diagnosis of unprotected left main coronary artery disease

Background

Patients with unprotected left main coronary artery disease (uLMCAD) have high mortality rate due to sudden heart failure and acute myocardial infarction, for which reliable diagnostic biomarkers to detect this disease at an early stage are in urgent need. Circulating microRNAs (miRNAs) have emerged as a class of novel biomarkers for cardiovascular diseases. The purpose of this study was to investigate utility of miRNAs as biomarkers for early detection of uLMCAD.

Methods

High-throughput sequencing (NGS) was initially employed to compare circulating miRNA expression profiles in uLMCAD patients to that in patients without coronary artery disease (CAD) to identify candidate miRNA biomarkers. We further validated the expression of candidate miRNAs by quantitative polymerase chain reaction (qPCR) in a larger cohort. Receiver operating characteristic (ROC) analysis with multivariate logistic regression was used to evaluate the diagnostic power of candidate miRNAs individually and combined.

Results

MiR-182-5p, miR-199a-5p and miR-5187-5p were found significantly differentially expressed through NGS (fold changes =1.35, 1.65, 0.5, P values =0.018, 0.046, 0.030, respectively, n=5 for both uLMCAD group and non-CAD control group). In a larger cohort (n=27 for uLMCAD patient and n=38 for non-CAD controls), qPCR confirmed that expression of miR-182-5p was up-regulated (2.57-fold, P=0.011) and expression of miR-5187-5p was down-regulated (0.47-fold, P=0.018) in the plasma of uLMCAD patients. ROC analysis with multivariate logistic regression show that miR-182 and miR-5187 have an AUC score of 0.97 and 0.94 respectively, indicating high diagnostic power as biomarkers for uLMCAD. Interestingly, correlation analysis suggests that the expression of two miRNAs were independent to each other.

Conclusions

These results suggested that circulating miR-182-5p and miR-5187-5p were suitable diagnostic biomarkers for uLMCAD, both potentially providing diagnostic information for discriminating uLMCAD patients from non-CAD population prior to invasive diagnostic coronary angiography (CAG).

Bioinformatic analysis of miR-4792 regulates Radix Tetrastigma hemsleyani flavone to inhibit proliferation, invasion, and induce apoptosis of A549 cells

BACKGROUND

Radix Tetrastigma hemsleyani, a kind of Chinese medicinal herb, contains multiple medicinal ingredients and can exert a variety of pharmacological activities. Our previous study revealed that miR-4792 was significantly upregulated in Radix Tetrastigma hemsleyani flavone (RTHF)-treated A549 cells; however, the regulatory mechanism of RTHF-treated A549 cells remains unclear.

MATERIALS AND METHODS

In this study, we investigated the antitumor mechanism and regulatory pathway of miR-4792 in RTHF-treated A549 cells, and the target genes were predicted and pathway enrichment of miR-4792 was performed using bioinformatic analysis.

RESULTS

Our results confirmed that the upregulated expression of miR-4792 could inhibit cell proliferation and invasion, provoke cell cycle arrest, and induce apoptosis in A549 cells. Gene Ontology analysis showed that target genes of miR-4792 were enriched in protein binding, cytosol, cytoplasm, plasma membrane, and metal ion binding. Kyoto Encyclopedia of Genes and Genomes analysis showed that target genes of miR-4792 were enriched in aminoacyltRNA biosynthesis, AGE-RAGE signaling pathway in diabetic complications, sphingolipid signaling pathway, neuroactive ligand-receptor interaction, glycosaminoglycan degradation, and regulation of lipolysis in adipocytes. Additionally, FOXC1 was identified as an important target gene of miR-4792 in RTHF-treated A549 cells, and miR-4792 may be the target of some apoptotic-related proteins involved in induction of apoptosis in A549 cells by RTHF. Moreover, the intracellular Ca2+ levels of A549 cells were increased after RTHF treatment, which may be involved in the anticancer regulatory process of miR-4792 in RTHF-treated A549 cells.

CONCLUSION

These findings suggest a novel therapeutic approach for lung cancer that will be investigated in future studies.

Correlation Between Tumor Vasculogenic Mimicry and Poor Prognosis of Human Digestive Cancer Patients: A Systematic Review and Meta-Analysis

Vasculogenic mimicry (VM) is a new pattern of blood supplement independent of endothelial vessels, which is related with tumor invasion, metastasis and prognosis. However, the role of VM in the prognosis of cancer patients is controversial. This study aimed to perform a meta-analysis of the published data to attempt to clarify the prognostic value of VM in the digestive cancer. Relevant studies were retrieved from the PubMed, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure and VIP databases published before March 29, 2018. Studies were included if they detected VM in the digestive cancer and analyzed the overall survival (OS) or disease-free survival (DFS) according to VM status. Two independent reviewers screened the studies, extracted data, and evaluated the quality of included studies with the Newcastle-Ottawa scale. Meta-analysis was performed using STATA 12.0 software. A total of 22 studies with 2411 patients were included in this meta-analysis. Meta-analysis showed that VM was related with the poor OS (HR = 2.30, 95% CI: 2.06-2.56, P < 0.001) and DFS (HR = 2.60, 95% CI: 2.07-3.27, P < 0.001) of patients with digestive cancer. Subgroup analysis showed VM was related with tumor differentiation, lymph node metastasis and TNM stage. Moreover, the present meta-analysis was reliable, and there was no obvious publication bias. This meta-analysis suggested that VM was a poor prognosis of digestive cancer patients. Further large and well-designed studies are required.

Perivascular cell coverage of intratumoral vasculature is a predictor for bevacizumab efficacy in metastatic colorectal cancer

Purpose

Tumor vessels supported by perivascular cells have been implicated in the failure of some anti-angiogenic agents. The relationship between perivascular cell coverage (PC) and bevacizumab efficacy in metastatic colorectal cancer (mCRC) was analyzed.

Patients and methods

A total of 284 consecutive mCRC patients who received first-line chemotherapy with or without bevacizumab from 2007-2014 in Sun Yat-Sen University Cancer Center were analyzed. Immunohistochemical double-stain for the perivascular cell marker alpha-smooth muscle actin and endothelial cell (cluster of differentiation 31) was performed to characterize the intratumoral microvascular density. Multispectral image capturing and computerized image analyses were used to quantify the microvessels supported by the perivascular cells. The patients were divided into high and low PC group according to a median cutoff value of 0.55.

Results

No significant differences in overall survival (OS) and progression-free survival (PFS) were noted between the high and low PC group. In the low PC group, the patients with bevacizumab treatment had favorable OS (P=0.03), but without PFS benefit. In the high PC group, neither OS nor PFS was significantly different between the B+C and C subgroup. Tumors with perineural invasion had high PC (P=0.03).

Conclusion

The data showed that a low PC value could be a predictor for bevacizumab benefit.

Comparative in vitro/theoretical studies on the anti-angiogenic activity of date pollen hydro-alcoholic extract: Highlighting the important roles of its hot polyphenols

Introduction: Date palm pollen (DPP) is the male reproductive soft powder from date flowers widely used as the valuable dietary supplement to fortify the size of testis and ovarian to increase the power of sex. This part of date palm significantly exhibited anti-diabetic, anti-inflammation and protective effects against male and female infertility. Though the anticancer activity of date fruits was previously reported, the DPP anti-angiogenic effects were not reported, and as the first study, its inhibitory effects were examined in the current study.

Methods: The DPP soft powder was collected to prepare its hydro-alcoholic extract to examine its anti-angiogenic activity in an in vitro model. At different concentrations, the cytotoxicity of the prepared extract was examined on human umbilical vein endothelial cells (HUVECs) using lactate dehydrogenase method. Cell proliferation was determined using the MTT assay and cytodex-3D model in collagen gel was used to assay its possible anti-angiogenic activity. The expression of VEGF, MMP-2 and MMP-9 genes was measured using real-time polymerase chain reaction (PCR). Finally, molecular docking simulation was used to highlight the possible role of DPP polyphenols to interact with the associated receptors.

Results: The prepared hydro-alcoholic extract exhibited significant anti-angiogenic activity in a dose-dependent manner and decreased the endothelial cell proliferation. The calculated IC₅₀ value for the examined extract in angiogenesis model was 260 µg·mL, respectively. Also, the expression of VEGF, MMP-2 and MMP-9 genes were significantly decreased. Docking simulation results unveiled that the isolated DPP polyphenols have the affinity to interact with ctDNA, VEGF and its receptors.

Conclusion: The DPP is the new source of non-toxic anti-cancer agents to use as a dietary supplement in the pre-treatment of cancer.

Network-Based Predictors of Progression in Head and Neck Squamous Cell Carcinoma

The heterogeneity in head and neck squamous cell carcinoma (HNSCC) has made reliable stratification extremely challenging. Behavioral risk factors such as smoking and alcohol consumption contribute to this heterogeneity. To help elucidate potential mechanisms of progression in HNSCC, we focused on elucidating patterns of gene interactions associated with tumor progression. We performed de-novo gene co-expression network inference utilizing 229 patient samples from The Cancer Genome Atlas (TCGA) previously annotated by Bornstein et al. (2016). Differential network analysis allowed us to contrast progressor and non-progressor cohorts. Beyond standard differential expression (DE) analysis, this approach evaluates changes in gene expression variance (differential variability DV) and changes in covariance, which we denote as differential wiring (DW). The set of affected genes was overlaid onto the co-expression network, identifying 12 modules significantly enriched in DE, DV, and/or DW genes. Additionally, we identified modules correlated with behavioral measures such as alcohol consumption and smoking status. In the module enriched for differentially wired genes, we identified network hubs including IL10RA, DOK2, APBB1IP, UBASH3A, SASH3, CELF2, TRAF3IP3, GIMAP6, MYO1F, NCKAP1L, WAS, FERMT3, SLA, SELPLG, TNFRSF1B, WIPF1, AMICA1, PTPN22; the network centrality and progression specificity of these genes suggest a potential role in tumor evolution mechanisms related to inflammation and microenvironment. The identification of this network-based gene signature could be further developed to guide progression stratification, highlighting how network approaches may help improve clinical research end points and ultimately aid in clinical utility.

Analysis of aqueous humor concentrations of cytokines in retinoblastoma

To investigate the components of the aqueous humor (AH) in patients with retinoblastoma (RB). We collected 0.1 ml AH of 35 children with RB and 20 patients with congenital cataracts as controls. Multiplex enzyme-linked immunosorbent assays (ELISAs) and Luminex xMAP technology were used to assess 45 cytokines/chemokines, matrix metalloproteinases (MMPs), and acute-phase proteins in the identification cohort. The concentrations of IL-6, IL-7, IL-8, IFN-γ, PIGF-1, VEGF-A, β-NGF, HGF, EGF and FGF-2 were significantly higher in the AH of patients with RB than those in the control group (P<0.05). The study showed that the higher levels of IP-10, IL-6, IL-7, IL-8, IFN-γ, PIGF-1, VEGF-A, β-NGF, HGF, EGF and FGF-2 in AH may be associated with RB. Our findings may facilitate a better understanding of the molecular pathways of tumors and solid molecular targets for new strategies for therapy and the earlier diagnosis of RB.

Differential Receptor Binding and Regulatory Mechanisms for the Lymphangiogenic Growth Factors Vascular Endothelial Growth Factor (VEGF)-C and -D

VEGF-C and VEGF-D are secreted glycoproteins that induce angiogenesis and lymphangiogenesis in cancer, thereby promoting tumor growth and spread. They exhibit structural homology and activate VEGFR-2 and VEGFR-3, receptors on endothelial cells that signal for growth of blood vessels and lymphatics. VEGF-C and VEGF-D were thought to exhibit similar bioactivities, yet recent studies indicated distinct signaling mechanisms (e.g. tumor-derived VEGF-C promoted expression of the prostaglandin biosynthetic enzyme COX-2 in lymphatics, a response thought to facilitate metastasis via the lymphatic vasculature, whereas VEGF-D did not). Here we explore the basis of the distinct bioactivities of VEGF-D using a neutralizing antibody, peptide mapping, and mutagenesis to demonstrate that the N-terminal α-helix of mature VEGF-D (Phe⁹³–Arg¹⁰⁸) is critical for binding VEGFR-2 and VEGFR-3. Importantly, the N-terminal part of this α-helix, from Phe⁹³ to Thr⁹⁸, is required for binding VEGFR-3 but not VEGFR-2. Surprisingly, the corresponding part of the α-helix in mature VEGF-C did not influence binding to either VEGFR-2 or VEGFR-3, indicating distinct determinants of receptor binding by these growth factors. A variant of mature VEGF-D harboring a mutation in the N-terminal α-helix, D103A, exhibited enhanced potency for activating VEGFR-3, was able to promote increased COX-2 mRNA levels in lymphatic endothelial cells, and had enhanced capacity to induce lymphatic sprouting in vivo. This mutant may be useful for developing protein-based therapeutics to drive lymphangiogenesis in clinical settings, such as lymphedema. Our studies shed light on the VEGF-D structure/function relationship and provide a basis for understanding functional differences compared with VEGF-C.

Future options of anti-angiogenic cancer therapy

In human patients, drugs that block tumor vessel growth are widely used to treat a variety of cancer types. Many rigorous phase 3 clinical trials have demonstrated significant survival benefits; however, the addition of an anti-angiogenic component to conventional therapeutic modalities has generally produced modest survival benefits for cancer patients. Currently, it is unclear why these clinically available drugs targeting the same angiogenic pathways produce dissimilar effects in preclinical models and human patients. In this article, we discuss possible mechanisms of various anti-angiogenic drugs and the future development of optimized treatment regimens.

Comparisons of biophysical properties and bioactivities of mono-PEGylated endostatin and an endostatin analog

Background

Endostatin (ES) is a well-established potent endogenous antiangiogenic factor. An ES variant, called zinc-binding protein-ES (ZBP-ES), is clinically available; however, its use is limited by rapid renal clearance and short residence time. PEGylation has been exploited to overcome these shortcomings, and mono-PEGylated ES (called M₂ES) as well as mono-PEGylated ZBP-ES (MZBP-ES) are developed in our study. This study aimed to compare the biophysical properties and biological effects of M₂ES and MZBP-ES to evaluate their druggability.

Methods

Circular dichroism and tryptophan emission fluorescence were used to monitor the conformational changes of M₂ES and MZBP-ES. Their resistance to trypsin digestion and guanidinium chloride (GdmCl)-induced unfolding was examined by Coomassie staining and tryptophan emission fluorescence, respectively. The biological effects of M₂ES and MZBP-ES on endothelial cell migration were evaluated using Transwell migration and wound healing assays, and the uptake of M₂ES and MZBP-ES in endothelial cells was also compared by Western blotting and immunofluorescence.

Results

Structural analyses revealed that M₂ES has a more compact tertiary structure than MZBP-ES. Moreover, M₂ES was more resistant to trypsin digestion and GdmCl-induced unfolding compared with MZBP-ES. In addition, although M₂ES and MZBP-ES showed comparable levels of inhibiting transwell migration and wound healing of endothelial cells, M₂ES displayed an increased ability to enter cells compared with MZBP-ES, possibly caused by the enhanced interaction with nucleolin.

Conclusions

M₂ES has a more compact tertiary structure, is more stable for trypsin digestion and GdmCl-induced unfolding, exhibits increased cellular uptake and shows equivalent inhibitory effects on cell migration relative to MZBP-ES, indicating that M₂ES is a more promising candidate for anticancer drug development compared with MZBP-ES.

Revisiting tumor angiogenesis: vessel co-option, vessel remodeling, and cancer cell-derived vasculature formation

Tumor growth and metastasis depend on the establishment of tumor vasculature to provide oxygen, nutrients, and other essential factors. The well-known vascular endothelial growth factor (VEGF) signaling is crucial for sprouting angiogenesis as well as recruitment of circulating progenitor endothelial cells to tumor vasculature, which has become therapeutic targets in clinical practice. However, the survival benefits gained from targeting VEGF signaling have been very limited, with the inevitable development of treatment resistance. In this article, we discuss the most recent findings and understanding on how solid tumors evade VEGF-targeted therapy, with a special focus on vessel co-option, vessel remodeling, and tumor cell-derived vasculature establishment. Vessel co-option may occur in tumors independently of sprouting angiogenesis, and sprouting angiogenesis is not always required for tumor growth. The differences between vessel-like structure and tubule-like structure formed by tumor cells are also introduced. The exploration of the underlying mechanisms of these alternative angiogenic approaches would not only widen our knowledge of tumor angiogenesis but also provide novel therapeutic targets for better controlling cancer growth and metastasis.

A plasma cytokine and angiogenic factor (CAF) analysis for selection of bevacizumab therapy in patients with metastatic colorectal cancer

This study intends to identify biomarkers that could refine the selection of patients with metastatic colorectal cancer (mCRC) for bevacizumab treatment. Pretreatment 36 plasma cytokines and angiogenic factors (CAFs) were first measured by protein microarray analysis in patients who received first-line bevacizumab-containing therapies (discovery cohort, n = 64), and further evaluated by enzyme-linked immunosorbent assay in patients treated on regimens with or without bevacizumab (validation cohort, n = 186). Factor levels were correlated with clinical outcomes, predictive values were assessed using a treatment by marker interaction term in the Cox model. Patients with lower pretreatment levels of hepatocyte growth factor (HGF) or VEGF-A¹²¹ gain much more benefit from bevacizumab treatment as measured by progression-free survival (PFS) and overall survival (OS), while angiopoietin-like 4 (ANGPTL4) levels negatively correlated with PFS and response rate following bevacizumab (all adjusted interaction P < 0.05). A baseline CAF signature combining these three markers has greater predictive ability than individual markers. Signature-negative patients showed impaired survival following bevacizumab treatment (PFS, 7.3 vs 7.0 months; hazard ratio [HR] 1.03; OS, 29.9 vs 21.1 months, HR 1.33) compared with signature-positive patients (PFS, 6.5 vs 11.9 months, HR 0.52; OS, 28.0 vs 55.3 months, HR 0.67). These promising results warrant further prospective studies.

Factor inhibiting HIF1α (FIH-1) functions as a tumor suppressor in human colorectal cancer by repressing HIF1α pathway

Colorectal cancer (CRC) is one of the most common cancers worldwide. The molecular mechanisms underlying CRC development involve a multistep process with the accumulation of both genetic and epigenetic changes. To deeply understand CRC tumorigenesis and progression, advances in identification of novel mechanisms and key factors are therefore in an urgent need. Here, we examined the correlation of factor inhibiting HIF-1α (FIH-1) expression with clinicopathological features of CRC. The finding that FIH-1 was not only significantly decreased in tumor tissue but also was significantly correlated with tumor invading depth, lymph node involvement, and metastasis suggested the role of FIH-1 as a tumor suppressor in CRC development. To further support the above hypothesis, we performed both in vitro and in vivo experiments to identify the role of FIH-1 in CRC development. FIH-1 was found to inhibit CRC cell proliferation, migration, invasion, and colony formation in vitro. FIH-1 was also shown to repress LOVO xenograft tumor growth in vivo. To decipher the mechanism, we examined the expression level of HIF-1α and its target genes. We found that FIH-1 was able to inhibit HIF1α mediated transcription of GLUT1 and VEGF in CRC cells. The above observation points to the possibility that loss or decreased expression of FIH-1 gene may lead to a constitutive activation of HIF1α and an alteration of HIF-1 targets such as GLUT-1 and VEGF. These findings highlight the critical role of FIH-1 in CRC and indicate FIH-1 functions as a tumor suppressor in human CRC by repressing HIF1α pathway.

Stem cell-derived exosomes: roles in stromal remodeling, tumor progression, and cancer immunotherapy

Stem cells are known to maintain stemness at least in part through secreted factors that promote stem-like phenotypes in resident cells. Accumulating evidence has clarified that stem cells release nano-vesicles, known as exosomes, which may serve as mediators of cell-to-cell communication and may potentially transmit stem cell phenotypes to recipient cells, facilitating stem cell maintenance, differentiation, self-renewal, and repair. It has become apparent that stem cell-derived exosomes mediate interactions among stromal elements, promote genetic instability in recipient cells, and induce malignant transformation. This review will therefore discuss the potential of stem cell-derived exosomes in the context of stromal remodeling and their ability to generate cancer-initiating cells in a tumor niche by inducing morphologic and functional differentiation of fibroblasts into tumor-initiating fibroblasts. In addition, the immunosuppressive potential of stem cell-derived exosomes in cancer immunotherapy and their prospective applications in cell-free therapies in future translational medicine is discussed.

Cytochrome b5 reductase 2 suppresses tumor formation in nasopharyngeal carcinoma by attenuating angiogenesis

Background

Cytochrome b5 reductase 2 (CYB5R2) is a potential tumor suppressor that inhibits cell proliferation and motility in nasopharyngeal carcinoma (NPC). Inactivation of CYB5R2 is associated with lymph node metastasis in NPC. This study aimed to explore the mechanisms contributing to the anti-neoplastic effects of CYB5R2.

Methods

Polymerase chain reaction (PCR) assays were used to analyze the transcription of 84 genes known to be involved in representative cancer pathways in the NPC cell line HONE1. NPC cell lines CNE2 and HONE1 were transiently transfected with CYB5R2, and data was validated by real-time PCR. A chick chorioallantoic membrane (CAM) embryo model was implanted with CYB5R2-expressing CNE2 and HONE1 cells to evaluate the effect of CYB5R2 on angiogenesis. An immunohistochemical assay of the CAM model was used to analyze the protein expression of vascular endothelial growth factor (VEGF).

Results

In CYB5R2-transfected NPC cells, PCR assays revealed up-regulated mRNA levels of Fas cell surface death receptor (FAS), FBJ murine osteosarcoma viral oncogene homolog (FOS), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), integrin beta 3 (ITGB3), metastasis suppressor 1 (MTSS1), interferon beta 1 (IFNB1), and cyclin-dependent kinase inhibitor 2A (CDKN2A) and down-regulated levels of integrin beta 5 (ITGB5), insulin-like growth factor 1 (IGF1), TEK tyrosine kinase (TEK), transforming growth factor beta receptor 1 (TGFBR1), and VEGF. The angiogenesis in the CAM model implanted with CYB5R2-transfected NPC cells was inhibited. Down-regulation of VEGF by CYB5R2 in NPC cells was confirmed by immunohistochemical staining in the CAM model.

Conclusion

CYB5R2 up-regulates the expression of genes that negatively modulate angiogenesis in NPC cells and down-regulates the expression of VEGF to reduce angiogenesis, thereby suppressing tumor formation.

Ziv-aflibercept in metastatic colorectal cancer

The combination of cytotoxic chemotherapy and antiangiogenic agents has become a conventional treatment option for patients with metastatic colorectal cancer. Ziv-aflibercept is a fusion protein which acts as a decoy receptor for vascular endothelial growth factor (VEGF)-A, VEGF-B, and placental growth factor (PlGF); it was approved in combination with 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) for the treatment of patients with metastatic colorectal cancer that is resistant to or has progressed after an oxaliplatin-containing fluoropyrimidine-based regimen. Herein we review the role of tumor angiogenesis as the rationale for antiangiogenic therapy, the clinical data associated with ziv-aflibercept, and its current role as a treatment option compared to other antiangiogenic agents, such as bevacizumab and regorafenib.