YC-1 Prevents Tumor-Associated Tissue Factor Expression and Procoagulant Activity in Hypoxic Conditions by Inhibiting p38/NF-κB Signaling Pathway

Boosting immune responses in lung tumor immune microenvironment: A comprehensive review of strategies and adjuvants

The immune system has a substantial impact on the growth and expansion of lung malignancies. Immune cells are encompassed by a stroma comprising an extracellular matrix (ECM) and different cells like stromal cells, which are known as the tumor immune microenvironment (TIME). TME is marked by the presence of immunosuppressive factors, which inhibit the function of immune cells and expand tumor growth. In recent years, numerous strategies and adjuvants have been developed to extend immune responses in the TIME, to improve the efficacy of immunotherapy. In this comprehensive review, we outline the present knowledge of immune evasion mechanisms in lung TIME, explain the biology of immune cells and diverse effectors on these components, and discuss various approaches for overcoming suppressive barriers. We highlight the potential of novel adjuvants, including toll-like receptor (TLR) agonists, cytokines, phytochemicals, nanocarriers, and oncolytic viruses, for enhancing immune responses in the TME. Ultimately, we provide a summary of ongoing clinical trials investigating these strategies and adjuvants in lung cancer patients. This review also provides a broad overview of the current state-of-the-art in boosting immune responses in the TIME and highlights the potential of these approaches for improving outcomes in lung cancer patients.

Discovery of 5-Hydroxy-1,4-naphthoquinone (Juglone) Derivatives as Dual Effective Agents Targeting Platelet-Cancer Interplay through Protein Disulfide Isomerase Inhibition

In this study, a series of 2- and/or 3-substituted juglone derivatives were designed and synthesized. Among them, 9, 18, 22, 30, and 31 showed stronger inhibition activity against cell surface PDI or recombinant PDI and higher inhibitory effects on U46619- and/or collagen-induced platelet aggregation than juglone. The glycosylated derivatives 18 and 22 showed improved selectivity for inhibiting the proliferation of multiple myeloma RPMI 8226 cells, and the IC50 values reached 61 and 48 nM, respectively, in a 72 h cell viability test. In addition, 18 and 22 were able to prevent tumor cell-induced platelet aggregation and platelet-enhanced tumor cell proliferation. The molecular docking showed the amino acid residues Gln243, Phe440, and Leu443 are important for the compound-protein interaction. Our results reveal the potential of juglone derivatives to serve as novel antiplatelet and anticancer dual agents, which are available to interrupt platelet-cancer interplay through covalent binding to PDI catalytic active site.

11,12-EET suppressed LPS induced TF expression and thrombus formation by accelerating mRNA degradation rate via strengthening PI3K-Akt signaling pathway and inhibiting p38-TTP pathway

Epoxyeicosatrienoic acids (EETs), which are synthesized from arachidonic acid by cytochrome P450 epoxygenases, function primarily as autocrine and paracrine effectors in the cardiovascular system. So far, most research has focused on the vasodilatory, anti-inflammatory, anti-apoptotic and mitogenic properties of EETs in the systemic circulation. However, whether EETs could suppress tissue factor (TF) expression and prevent thrombus formation remains unknown. Here we utilized in vivo and in vitro models to investigate the effects and underlying mechanisms of exogenously EETs on LPS induced TF expression and inferior vein cava ligation induced thrombosis. We observed that the thrombus formation rate and the size of the thrombus were greatly reduced in 11,12-EET treated mice，accompanied by decreased TF and inflammatory cytokines expression. Further in vitro studies showed that by enhancing p38 MAPK activation and subsequent tristetraprolin (TTP) phosphorylation, LPS strengthened the stability of TF mRNA and induced increased TF expression. However, by strengthening PI3K-dependent Akt phosphorylation, which acted as a negative regulator of p38-TTP signaling pathway，11,12-EET reduced LPS-induced TF expression in monocytes. In addition, 11,12-EET inhibited LPS-induced NF-κB nuclear translocation by activating the PI3K/Akt pathway. Further study indicated that the inhibitory effect of 11,12-EET on TF expression was mediated by antagonizing LPS-induced activation of thromboxane prostanoid receptor. In conclusion, our study demonstrated that 11,12-EET prevented thrombosis by reducing TF expression and targeting the CYP2J2 epoxygenase pathway may represent a novel approach to mitigate thrombosis related diseases.

Advances in antitumor research of HIF-1α inhibitor YC-1 and its derivatives

Generally, hypoxia-inducible factor-1α (HIF-1α) is highly expressed in solid tumors, it plays a key role in the occurrence and development of tumors, hindering cancer treatment in various ways. The antitumor activity and pharmacological mechanism of YC-1 [3-(5'-hydroxymethyl-2'-furyl)-1‑benzyl indazole], an HIF-1α inhibitor, and the design and synthesis of its derivatives have attracted tremendous attention in the field of antitumor research. YC-1 is a potential drug candidate and a lead compound for tumor therapy. Hence, the multifaceted mechanism of action of YC-1 and the structure activity relationship (SAR) of its derivatives are important factors to be considered for the development of HIF-1α inhibitors. Therefore, this review aimed to provide a comprehensive overview of the various antitumor mechanisms of YC-1 in antitumor research and an in-depth summary of the SAR for the development of its derivatives. A full understanding and discussion of these aspects are expected to provide potential ideas for developing novel HIF-1α inhibitors and antitumor drugs belonging to the YC-1 class. The review also highlighted the application prospects of the YC-1 class of potential antitumor candidates, and provided some unique insights about these antitumor agents.

Advances in the Prediction and Risk Assessment of Lung Cancer-Associated Venous Thromboembolism

According to the most recent data from the National Cancer Center, venous thromboembolism (VTE) has unsurprisingly become one of the most common complications in lung cancer. VTE not only interferes with the equilibrium of the clotting system but it also affects tumor progression and prognosis. For the identification of high-risk patients, many clinical risk assessment models have been developed and validated based on the risk factors found in previous studies. In this review, we will summarize advances in prediction and risk assessment of VTE, with a focus on early diagnosis and therapy, reduction of mortality, and the burden of medical costs in lung cancer patients.

Codelivery of High-Molecular-Weight Poly-porphyrins and HIF-1α Inhibitors for In Vivo Synergistic Anticancer Therapy

Photodynamic therapy (PDT) is showing great potential in the treatment of cancer diseases, and photosensitizers play crucial roles in absorbing the energy of light and generating reactive oxygen species (ROS) during PDT. Most of the photosensitizers bearing macrocyclic structures have strong hydrophobicity and suffer from the π-π interaction and undesired aggregation caused quenching (ACQ), which severely limit the PDT efficacy. Moreover, the continuous oxygen consumption during PDT also leads to the upregulated expression of hypoxia-inducible factor-1α (HIF-1α), which can aggravate the growth of tumors. To overcome the abovementioned problems, polymerized photosensitizers repelled by flexible thioketal linkers were designed and synthesized using a multicomponent polymerization (MCP) method to afford the poly-porphyrins with high molecular weight (M_w > 20 000 g/mol) under room temperature. The ACQ effect could be significantly inhibited by introducing flexible chains and increasing M_w, leading to the improvement in the singlet oxygen quantum yield and phototoxicity simultaneously. An HIF-1α inhibitor, Lificiguat (YC-1) was synthesized as a chemodrug and codelivered with poly-porphyrins to decrease the expression of HIF-1α and inhibit tumor growth under hypoxia. With the synergistic PDT and chemotherapy, poly-porphyrin/YC-1 micelles showed excellent therapeutic antitumor efficacy both in vitro and in vivo.

Chronic and Cycling Hypoxia: Drivers of Cancer Chronic Inflammation through HIF-1 and NF-κB Activation: A Review of the Molecular Mechanisms

Chronic (continuous, non-interrupted) hypoxia and cycling (intermittent, transient) hypoxia are two types of hypoxia occurring in malignant tumors. They are both associated with the activation of hypoxia-inducible factor-1 (HIF-1) and nuclear factor κB (NF-κB), which induce changes in gene expression. This paper discusses in detail the mechanisms of activation of these two transcription factors in chronic and cycling hypoxia and the crosstalk between both signaling pathways. In particular, it focuses on the importance of reactive oxygen species (ROS), reactive nitrogen species (RNS) together with nitric oxide synthase, acetylation of HIF-1, and the action of MAPK cascades. The paper also discusses the importance of hypoxia in the formation of chronic low-grade inflammation in cancerous tumors. Finally, we discuss the effects of cycling hypoxia on the tumor microenvironment, in particular on the expression of VEGF-A, CCL2/MCP-1, CXCL1/GRO-α, CXCL8/IL-8, and COX-2 together with PGE₂. These factors induce angiogenesis and recruit various cells into the tumor niche, including neutrophils and monocytes which, in the tumor, are transformed into tumor-associated neutrophils (TAN) and tumor-associated macrophages (TAM) that participate in tumorigenesis.

Schisandrin B inhibits epithelial‑mesenchymal transition and stemness of large‑cell lung cancer cells and tumorigenesis in xenografts via inhibiting the NF‑κB and p38 MAPK signaling pathways

Lung cancer is one of the most common types of cancer in the world, resulting in numerous cancer-associated deaths. The properties of cancer stem cells (CSCs) are important for the initiation and deterioration of lung cancer. Schisandrin B (SchB), an active compound extracted from Schisandra chinensis, exerts anticancer effects in various malignancies, including lung cancer. Nevertheless, the potential of SchB in epithelial-mesenchymal transition (EMT) and CSC features of large-cell lung cancer remains unclear. The present study established cancer stem-like cells derived from large-cell lung cancer cells, NCI-H460 and H661, and revealed that SchB inhibited the viability of cancer stem-like cells at concentrations of ≥40 µmol/l. Moreover, SchB prominently inhibited cell migration, invasion and EMT. Sphere-forming assays and western blotting demonstrated that the stemness of cancer stem-like cells was alleviated by SchB treatment. Mechanistically, the current findings revealed that SchB contributed to the suppression of the NF-κB and p38 MAPK signaling pathways. Notably, further results revealed that the malignant behaviors of NCI-H460-CSCs induced by the activation of the NF-κB and p38 MAPK signaling pathways were suppressed by SchB treatment. Consistently, the inhibitory role of SchB in EMT and CSC activities, as well as in the activation of the NF-κB and p38 MAPK signaling pathways, was confirmed in vivo. In conclusion, the present study demonstrated that SchB exerted inhibitory effects on large-cell lung cancer cells via targeting the NF-κB and p38 MAPK signaling pathways, suggesting that SchB may act as a potential therapeutic drug for large-cell lung cancer.

Golden berry 4β-hydroxywithanolide E prevents tumor necrosis factor α-induced procoagulant activity with enhanced cytotoxicity against human lung cancer cells

Inflammation in the tumor microenvironment is positively correlated with cancer progression and metastasis as well as the risk of thromboembolism in lung cancer patients. Here we show, in human non-small cell lung cancer (NSCLC) cell lines, the master inflammatory cytokine tumor necrosis factor (TNF-α) induced tissue factor expression and procoagulant activity, and these effects were potently inhibited by 4β-hydroxywithanolide E (4HW), a natural compound isolated from Physalis peruviana. Furthermore, combination of 4HW and TNF-α caused synergistic cytotoxicity against NSCLC cells by inducing caspase-dependent apoptosis. The underlying mechanism by which 4HW reverses the procoagulant effect of TNF-α but enhances its cytotoxic effect appears to be due to inhibition of NF-κB, which is a key switch for both inflammation-induced coagulation and cell survival. Our results suggest that 4HW may have a potential application for treating inflammation-derived cancer progression and cancer-associated hypercoagulable state.

Comparison of VEGF-A secretion from tumor cells under cellular stresses in conventional monolayer culture and microfluidic three-dimensional spheroid models

Vascular endothelial growth factor (VEGF) is a major cytokine in tumor biology affecting tumor survival, aggressiveness and pro-angiogenetic activities. In addition, cellular stresses often result in aggressive pro-angiogenetic behavior in tumors. For in vitro study, conventional monolayer cell culture has been broadly exploited; however, it often provides limited information due to its different microenvironment from that in vivo. Recently, three-dimensional (3D) cell spheroid culture provides in vivo-like microenvironments to study tumor biology and their survival mechanisms with better predictive power. In this work, vascular endothelial growth factor of type A (VEGF-A) secretion from osteosarcoma (MG-63) cells cultured using monolayer and 3D spheroid models under two stress conditions: nutrient deficiency (reduced serum culture) and hypoxia-inducible factor (HIF) inhibition (HIF inhibitor, YC-1) are characterized and systematically compared. In order to obtain ample sample size for consistent characterization of cellular responses from cancer spheroids under the stresses and compare the responses to those from the conventional monolayer model, a microfluidic spheroid formation and culture device is utilized in the experiments. In the analysis, cell viability is estimated from captured images, and quantification of VEGF-A secreted from the cells is achieved using enzyme-linked immunosorbent assay (ELISA). The experimental results show that the viabilities decrease when the cells face higher stress levels in both monolayer and 3D spheroid culture models; however, the VEGF-A secretion profiles between the cell culture models are different. The VEGF-A secretion decreases when the cells face higher stress conditions in the monolayer cell culture. In contrast, for the 3D spheroid culture, the VEGF-A concentration decreases for low stress levels but increases while the stress level is high. The VEGF-A regulation in the 3D models mimics in vivo cases of tumor survival and can provide insightful information to investigate tumor angiogenesis in vitro. The approach developed in this paper provides an efficient method to quantitatively and statistically study tumor growth kinetics and stress responses from highly uniform samples and it can also be applied to compare the underlying biomolecular mechanisms in monolayer and 3D spheroid culture models to elucidate the effects of microenvironments on cellular response in cancer research.

YC-1 Antagonizes Wnt/β-Catenin Signaling Through the EBP1 p42 Isoform in Hepatocellular Carcinoma

Novel drugs targeting Wnt signaling are gradually being developed for hepatocellular carcinoma (HCC) treatment. In this study, we used a Wnt-responsive Super-TOPflash (STF) luciferase reporter assay to screen a new compound targeting Wnt signaling. 3-(5'-Hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1) was identified as a small molecule inhibitor of the Wnt/β-catenin pathway. Our coimmunoprecipitation (co-IP) data showed that YC-1 did not affect the β-catenin/TCF interaction. Then, by mass spectrometry, we identified the ErbB3 receptor-binding protein 1 (EBP1) interaction with the β-catenin/TCF complex upon YC-1 treatment. EBP1 encodes two splice isoforms, p42 and p48. We further demonstrated that YC-1 enhances p42 isoform binding to the β-catenin/TCF complex and reduces the transcriptional activity of the complex. The suppression of colony formation by YC-1 was significantly reversed after knockdown of both isoforms (p48 and p42); however, the inhibition of colony formation was maintained when only EBP1 p48 was silenced. Taken together, these results suggest that YC-1 treatment results in a reduction in Wnt-regulated transcription through EBP1 p42 and leads to the inhibition of tumor cell proliferation. These data imply that YC-1 is a drug that antagonizes Wnt/β-catenin signaling in HCC.