Angiogenesis inhibitors in the treatment of non-small cell lung cancer

Sanikovich V, S. Rusanov A, N. Pirogova Y, Boroda A, Rozhkov A, Kemfang Ngowa JD, N. Bagmet L, I. Sekacheva M. Angiogenesis in Lung Cancer: Understanding the Roles of Growth Factors

Research has shown the role of growth factors in lung cancer angiogenesis. Angiogenesis promotes lung cancer progression by stimulating tumor growth, enhancing tumor invasion, contributing to metastasis, and modifying immune system responses within the tumor microenvironment. As a result, new treatment techniques based on the anti-angiogenic characteristics of compounds have been developed. These compounds selectively block the growth factors themselves, their receptors, or the downstream signaling pathways activated by these growth factors. The EGF and VEGF families are the primary targets in this approach, and several studies are being conducted to propose anti-angiogenic drugs that are increasingly suitable for the treatment of lung cancer, either as monotherapy or as combined therapy. The efficacy of the results are encouraging, but caution must be placed on the higher risk of toxicity, outlining the importance of personalized follow-up in the management of these patients.

Tissue factor (coagulation factor III): a potential double-edge molecule to be targeted and re-targeted toward cancer

Tissue factor (TF) is a protein that plays a critical role in blood clotting, but recent research has also shown its involvement in cancer development and progression. Herein, we provide an overview of the structure of TF and its involvement in signaling pathways that promote cancer cell proliferation and survival, such as the PI3K/AKT and MAPK pathways. TF overexpression is associated with increased tumor aggressiveness and poor prognosis in various cancers. The review also explores TF's role in promoting cancer cell metastasis, angiogenesis, and venous thromboembolism (VTE). Of note, various TF-targeted therapies, including monoclonal antibodies, small molecule inhibitors, and immunotherapies have been developed, and preclinical and clinical studies demonstrating the efficacy of these therapies in various cancer types are now being evaluated. The potential for re-targeting TF toward cancer cells using TF-conjugated nanoparticles, which have shown promising results in preclinical studies is another intriguing approach in the path of cancer treatment. Although there are still many challenges, TF could possibly be a potential molecule to be used for further cancer therapy as some TF-targeted therapies like Seagen and Genmab's tisotumab vedotin have gained FDA approval for treatment of cervical cancer. Overall, based on the overviewed studies, this review article provides an in-depth overview of the crucial role that TF plays in cancer development and progression, and emphasizes the potential of TF-targeted and re-targeted therapies as potential approaches for the treatment of cancer.

A review of recent advances in the novel therapeutic targets and immunotherapy for lung cancer

Lung cancer is amongst the most pervasive malignancies having high mortality rates. It is broadly grouped into non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). The concept of personalized medicine has overshadowed the conventional chemotherapy given to all patients with lung cancer. The targeted therapy is given to a particular population having specific mutations to help in the better management of lung cancer. The targeting pathways for NSCLC include the epidermal growth factor receptor, vascular endothelial growth factor receptor, MET (Mesenchymal epithelial transition factor) oncogene, Kirsten rat sarcoma viral oncogene (KRAS), and anaplastic lymphoma kinase (ALK). SCLC targeting pathway includes Poly (ADP-ribose) polymerases (PARP) inhibitors, checkpoint kinase 1 (CHK 1) pathway, WEE1 pathway, Ataxia Telangiectasia and Rad3-related (ATR)/Ataxia telangiectasia mutated (ATM), and Delta-like canonical Notch ligand 3 (DLL-Immune checkpoint inhibitors like programmed cell death protein 1 (PD-1)/ programmed death-ligand 1 (PD-L1) inhibitors and Cytotoxic T-lymphocyte-associated antigen-4 (CTLA4) blockade are also utilized in the management of lung cancer. Many of the targeted therapies are still under development and require clinical trials to establish their safety and efficacy. This review summarizes the mechanism of molecular targets and immune-mediated targets, recently approved drugs, and their clinical trials for lung cancer.

Cholesterol-lowering drug pitavastatin targets lung cancer and angiogenesis via suppressing prenylation-dependent Ras/Raf/MEK and PI3K/Akt/mTOR signaling

Therapeutic agents that target both tumor cell and vascular endothelial cell may achieve additional anti-tumor efficacy, particularly in lung cancer due to the critical roles of angiogenesis during lung cancer progression and metastasis. In this work, we showed that pitavastatin, a novel cholesterol-lowering drug, potently inhibited lung cancer cells and angiogenesis. This was achieved by the induction of apoptosis and inhibition of proliferation of lung cancer cells and human lung tumor-associated endothelial cell. Pitavastatin was not only effective to chemo-sensitive but also chemo-resistant lung cancer cells. This was also consistent with the finding that pitavastatin significantly enhanced cisplatin's efficacy in lung cancer xenograft model without causing toxicity in mice. We further showed that pitavastatin inhibited lung tumor angiogenesis in vitro and in vivo through suppressing human lung tumor-associated endothelial cell migration and morphogenesis without affecting adhesion. Mechanistically, we showed that pitavastatin acted on lung cancer cells and human lung tumor-associated endothelial cell through suppressing prenylation-dependent Ras/Raf/MEK and PI3K/Akt/mTOR signaling. Our work is the first to demonstrate the inhibitory effects of pitavastatin on Ras-mediated signaling. Our findings provide pre-clinical evidence to repurpose pitavastatin for the treatment of lung cancer.

Inhibition of eIF4E signaling by ribavirin selectively targets lung cancer and angiogenesis

Although the introduction of immune- and targeted-therapy has improved the clinical response and outcomes, lung cancer remains a therapeutic challenge. Developing new therapeutics is necessary to improve the treatment of lung cancer. Here, we show that ribavirin, a clinically available anti-viral drug, is an attractive candidate for lung cancer treatment. We show that ribavirin is active against a panel of lung cancer cell lines regardless of molecular and cellular heterogeneity. Notably, the effective concentrations of ribavirin are clinically achievable, display minimal toxicity to normal cells and synergistic effect with paclitaxel. Its potent efficacy and synergism with chemotherapy on cancer cell, and minimal toxicity on normal cells are observed in lung xenograft mouse model. Ribavirin is also an angiogenesis inhibitor as it inhibits capillary network formation, growth and survival of human lung tumor-associated endothelial cell (HLT-EC). The mechanism studies demonstrate that ribavirin acts on lung cancer cells via suppressing eIF4E and mTOR signaling, leading to the subsequent inhibition of eIF4E-mediated protein translation. Our work suggests that ribavirin has advantage than many anti-cancer agents by targeting both tumor cells and angiogenesis. Our work also highlights the therapeutic potential of ribavirin for the treatment of lung cancer.

Antibiotic bedaquiline effectively targets growth, survival and tumor angiogenesis of lung cancer through suppressing energy metabolism

Tumor angiogenesis plays essential roles during lung cancer progression and metastasis. Therapeutic agent that targets both tumor cell and vascular endothelial cell may achieve additional anti-tumor efficacy. We demonstrate that bedaquiline, a FDA-approved antibiotic drug, effectively targets lung cancer cells and angiogenesis. Bedaquiline dose-dependently inhibits proliferation and induces apoptosis of a panel of lung cancer cell lines regardless of subtypes and molecular heterogeneity. Bedaquiline also inhibits capillary network formation of human lung tumor associated-endothelial cell (HLT-EC) on Matrigel and its multiple functions, such as spreading, proliferation and apoptosis, even in the presence of vascular endothelial growth factor (VEGF). We further demonstrate that bedaquiline acts on lung cancer cells and HLT-EC via inhibiting mitochondrial respiration and glycolysis, leading to ATP reduction and oxidative stress. Consistently, oxidative damage on DNA, protein and lipid were detected in cells exposed to bedaquiline. Importantly, the results obtained in in vitro cell culture are reproducible in in vivo xenograft lung cancer mouse model, confirming that bedaquiline suppresses lug tumor growth and angiogenesis, and increases oxidative stress. Our findings demonstrating that energy depletion is effectively against lung tumor cells and angiogenesis. Our work also provide pre-clinical evidence to repurpose antibiotic bedaquiline for lung cancer treatment.

Azithromycin effectively inhibits tumor angiogenesis by suppressing vascular endothelial growth factor receptor 2-mediated signaling pathways in lung cancer

Tumor angiogenesis is essential during lung cancer development and targeting angiogenesis may possess a potential therapeutic value. The present study demonstrates that azithromycin, a Food and Drug Administration-approved antibiotic drug, is a novel tumor angiogenesis inhibitor. Azithromycin inhibits capillary network formation of human lung tumor associated-endothelial cells (HLT-ECs) in vitro and in vivo. It significantly inhibits HLT-EC adhesion and vascular endothelial growth factor (VEGF)-induced proliferation of HLT-ECs in a dose-dependent manner without affecting migration. In addition, azithromycin induces apoptosis of HLT-ECs even in the presence of VEGF. Notably, azithromycin inhibits proliferation and induces apoptosis in multiple lung cancer cell lines to a significantly reduced extent compared with in HLT-ECs, suggesting that HLT-ECs are more susceptible to azithromycin treatment. In a lung tumor xenograft model, azithromycin significantly inhibits tumor growth and its anti-tumor activities are achieved by suppressing angiogenesis. Notably, the inhibitory effects of azithromycin on angiogenesis are associated with its ability to suppress VEGF-induced activation of VEGF receptor 2 (VEGFR2), phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt), focal adhesion kinase, and disruption of focal adhesion assembly and actin stress fiber formation in HLT-ECs. The present study identifies that azithromycin targets VEGFR2-mediated focal adhesion and PI3K/Akt signaling pathways in HLT-ECs, leading to the suppression of angiogenesis and lung tumor growth.

Proteomic profiling of lung adenocarcinoma indicates heightened DNA repair, antioxidant mechanisms and identifies LASP1 as a potential negative predictor of survival

BACKGROUND

Lung cancer is the leading cause of cancer mortality in the United States. Non-small cell lung cancer accounts for 85% of all lung cancers for which adenocarcinoma is the most common histological type. Management of lung cancer is hindered by high false-positive rates due to difficulty resolving between benign and malignant tumors. Better molecular analysis comparing malignant and non-malignant tissues will provide important evidence of the underlying biology contributing to tumorigenesis.

METHODS

We utilized a proteomics approach to analyze 38 malignant and non-malignant paired tissue samples obtained from current or former smokers with early stage (Stage IA/IB) lung adenocarcinoma. Statistical mixed effects modeling and orthogonal partial least squares discriminant analysis were used to identify key cancer-associated perturbations in the adenocarcinoma proteome. Identified proteins were subsequently assessed against clinicopathological variables.

RESULTS

Top cancer-associated protein alterations were characterized by: (1) elevations in APEX1, HYOU1 and PDIA4, indicative of increased DNA repair machinery and heightened anti-oxidant defense mechanisms; (2) increased LRPPRC, STOML2, COPG1 and EPRS, suggesting altered tumor metabolism and inflammation; (3) reductions in SPTB, SPTA1 and ANK1 implying dysregulation of membrane integrity; and (4) decreased SLCA41 suggesting altered pH regulation. Increased protein levels of HYOU1, EPRS and LASP1 in NSCLC adenocarcinoma was independently validated by tissue microarray immunohistochemistry. Immunohistochemistry for HYOU1 and EPRS indicated AUCs of 0.952 and 0.841, respectively, for classifying tissue as malignant. Increased LASP1 correlated with poor overall survival (HR 3.66 per unit increase; CI 1.37-9.78; p = 0.01).

CONCLUSION

These results reveal distinct proteomic changes associated with early stage lung adenocarcinoma that may be useful prognostic indicators and therapeutic targets.

Sanguinarine is a novel VEGF inhibitor involved in the suppression of angiogenesis and cell migration

Vascular endothelial growth factor (VEGF) is a main angiogenic factor which is known to be upregulated in lung cancer. In the present study, it was demonstrated that sanguinarine, an alkaloid obtained from the bloodroot plant, markedly repressed the VEGF-induced tube formation of human microvascular endothelial cells (HMVECs) and the migration of human A549 lung cancer cells. Furthermore, sanguinarine decreased VEGF secretion and expression in HMVECs and A549 lung cancer cells in a dose- and time-dependent manner. Additionally, sanguinarine inhibited the activation of serum starvation- and hypoxia-induced VEGF promoter activity. Sanguinarine also inhibited the VEGF-mediated Akt and p38 activation, as well as VE-cadherin protein phosphorylation. To the best of our knowledge, this is the first study demonstrating that VEGF inhibition appears to be an important mechanism involved in the antiangiogenic and anti-invasive activities of sanguinarine in lung cancer treatment.