Novel angiogenesis inhibitors in nonsmall cell lung cancer

Effectiveness of Lomustine Combined With Bevacizumab in Glioblastoma: A Meta-Analysis

Introduction: Despite surgical and chemotherapeutical treatment options, the prognosis for glioblastoma (GBM) remains poor. Some studies have found that using lomustine plus bevacizumab to treat GBM can prolong overall survival (OS) and progression-free survival (PFS). The aim of this study was to explore the efficacy of the two drugs in combination treatment of GBM using a meta-analysis of the existing literature to help settle the ongoing debate. Materials and Methods: PubMed, EMBASE, and the Cochrane Library were searched for the effectiveness of lomustine plus bevacizumab in GBM literature, updated on June 6, 2020. The main outcomes analyzed included PFS and OS; the effects of this drug combination on the 6-month PFS, which represents the percentage of patients who had PFS for 6 months, were also analyzed. All the data were pooled: OS and PFS with the mean difference (MD) and 6-month PFS with the risk ratio (RR). Because there were different control groups and dose groups, two subgroup analyses were run to ensure they were comparable. All statistical analyses were performed using the Review Manager Version 5.3 software. Results: Six clinical trials were identified which included 1,095 patients (treatment group: 516; control group: 579). The group treated with lomustine and bevacizumab showed an improvement in OS (MD =1.37; 95% CI, 0.49-2.25; p = 0.002), PFS (MD = 0.23; 95% CI, 0.13-0.34; p < 0.00001), and 6-month PFS (RR = 2.29; 95% CI, 1.43-3.65; p = 0.0005). Two subgroup analyses of the main outcome, OS, show that the results of Control group A (p = 0.01) and Dose group 2 (p = 0.003) are significantly different from those of the other control or dose groups. Conclusion: This study shows that lomustine and bevacizumab can effectively increase OS, PFS, and 6-month PFS in patients with GBM. The encouraging results of the lomustine and bevacizumab combination therapy for GBM should be studied in more clinical trials in the future.

Angiogenesis in NSCLC: is vessel co-option the trunk that sustains the branches?

The critical role of angiogenesis in tumor development makes its inhibition a valuable new approach in therapy, rapidly making anti-angiogenesis a major focus in research. While the VEGF/VEGFR pathway is the main target of the approved anti-angiogenic molecules in NSCLC treatment, the results obtained are still modest, especially due to resistance mechanisms. Accumulating scientific data show that vessel co-option is an alternative mechanism to angiogenesis during tumor development in well-vascularized organs such as the lungs, where tumor cells highjack the existing vasculature to obtain its blood supply in a non-angiogenic fashion. This can explain the low/lack of response to current anti-angiogenic strategies. The same principle applies to lung metastases of other primary tumors. The exact mechanisms of vessel co-option need to be further elucidated, but it is known that the co-opted vessels regress by the action of Angiopoietin-2 (Ang-2), a vessel destabilizing cytokine expressed by the endothelial cells of the pre-existing mature vessels. In the absence of VEGF, vessel regression leads to tumor cell loss and hypoxia, with a subsequent switch to a neoangiogenic phenotype by the remaining tumor cells. Unravelling the vessel co-option mechanisms and involved players may be fruitful for numerous reasons, and the particularities of this form of vascularization should be carefully considered when planning anti-angiogenic interventions or designing clinical trials for this purpose. In view of the current knowledge, rationale for therapeutic approaches of dual inhibition of Ang-2 and VEGF are swiftly gaining strength and may serve as a launchpad to more successful NSCLC anti-vascular treatments.

Randomized Phase II Trial of Parsatuzumab (Anti-EGFL7) or Placebo in Combination with Carboplatin, Paclitaxel, and Bevacizumab for First-Line Nonsquamous Non-Small Cell Lung Cancer

Lessons Learned.

The lack of efficacy associated with anti‐EGFL7 combined with standard bevacizumab and chemotherapy in this phase II trial in non‐small cell lung carcinoma is consistent with the lack of benefit observed in colorectal carcinoma, highlighting the challenge of enhancing the efficacy of VEGF inhibition in unselected populations.

Future efforts with agents like anti‐EGFL7 should be guided by advances in pharmacodynamic and predictive biomarker development for antiangiogenic agents.

Background.

Epidermal growth factor‐like domain 7 (EGFL7) is an extracellular matrix‐associated protein that is upregulated during angiogenesis and supports endothelial cell survival. This phase II trial evaluated the efficacy of the anti‐EGFL7 antibody, parsatuzumab, in combination with bevacizumab plus platinum‐based therapy for advanced or recurrent nonsquamous non‐small cell lung cancer (NS‐NSCLC).

Methods.

Patients (n = 104) were randomized to either placebo or parsatuzumab (600 mg) in combination with bevacizumab (15 mg/kg) and carboplatin/paclitaxel, administered on day 1 of each 21‐day cycle. Carboplatin and paclitaxel were administered for up to six cycles. Bevacizumab and parsatuzumab/placebo were administered for a maximum of 24 months.

Results.

The progression‐free survival (PFS) hazard ratio (HR) was 1.7 (95% confidence interval [CI], 1.0–2.8; p = .047). The median PFS was 6.7 months for the parsatuzumab arm versus 8.1 months for the placebo arm. The hazard ratio for overall survival (OS) was 1.1 (95% CI, 0.5–2.2; p = .847). The objective response rate (ORR) was 29% in the parsatuzumab arm and 56% in the placebo arm. Overall safety and tolerability were consistent with the established toxicity profile of bevacizumab.

Conclusion.

There was no evidence of efficacy for the addition of parsatuzumab to the combination of bevacizumab and chemotherapy for first‐line NS‐NSCLC.

Triple Angiokinase Inhibitor Nintedanib Directly Inhibits Tumor Cell Growth and Induces Tumor Shrinkage via Blocking Oncogenic Receptor Tyrosine Kinases

The triple-angiokinase inhibitor nintedanib is an orally available, potent, and selective inhibitor of tumor angiogenesis by blocking the tyrosine kinase activities of vascular endothelial growth factor receptor (VEGFR) 1-3, platelet-derived growth factor receptor (PDGFR)-α and -β, and fibroblast growth factor receptor (FGFR) 1-3. Nintedanib has received regulatory approval as second-line treatment of adenocarcinoma non-small cell lung cancer (NSCLC), in combination with docetaxel. In addition, nintedanib has been approved for the treatment of idiopathic lung fibrosis. Here we report the results from a broad kinase screen that identified additional kinases as targets for nintedanib in the low nanomolar range. Several of these kinases are known to be mutated or overexpressed and are involved in tumor development (discoidin domain receptor family, member 1 and 2, tropomyosin receptor kinase A (TRKA) and C, rearranged during transfection proto-oncogene [RET proto oncogene]), as well as in fibrotic diseases (e.g., DDRs). In tumor cell lines displaying molecular alterations in potential nintedanib targets, the inhibitor demonstrates direct antiproliferative effects: in the NSCLC cell line NCI-H1703 carrying a PDGFRα amplification (ampl.); the gastric cancer cell line KatoIII and the breast cancer cell line MFM223, both driven by a FGFR2 amplification; AN3CA (endometrial carcinoma) bearing a mutated FGFR2; the acute myeloid leukemia cell lines MOLM-13 and MV-4-11-B with FLT3 mutations; and the NSCLC adenocarcinoma LC-2/ad harboring a CCDC6-RET fusion. Potent kinase inhibition does not, however, strictly translate into antiproliferative activity, as demonstrated in the TRKA-dependent cell lines CUTO-3 and KM-12. Importantly, nintedanib treatment of NCI-H1703 tumor xenografts triggered effective tumor shrinkage, indicating a direct effect on the tumor cells in addition to the antiangiogenic effect on the tumor stroma. These findings will be instructive in guiding future genome-based clinical trials of nintedanib.

Use of animal models for the imaging and quantification of angiogenesis

Angiogenesis is the process of developing new blood vessels from the original vascular network; it is necessary for normal physiological processes, such as embryonic development and wound healing. Angiogenesis is also involved in pathological events, including myocardial ischemia and tumor growth. To investigate the molecular mechanisms of this important process, a variety of methods and models are employed. These strategies can also be used to provide insight into the etiology of angiogenesis-related diseases, thereby contributing to the development of new diagnostics and treatments. Commonly used animal models include the chorioallantoic membrane and yolk sac membrane of chick embryos, the mouse retina and aortic ring, and angiogenesis reactors implanted into mice. These animal models have been instrumental in the study of the angiogenic process. For example, the chorioallantoic membrane undergoes robust angiogenesis during the development of chick embryos, and, because its surface is easily accessible, this membrane provides a convenient model for experimentation. Here, we discuss the methods that employ animal models for the imaging and quantification of angiogenesis. In addition, we propose potential novel directions for future investigations in this area.

Progression-free and overall survival in patients with recurrent Glioblastoma multiforme treated with last-line bevacizumab versus bevacizumab/lomustine

Bevacizumab (BEV) is widely used for treatment of patients with recurrent glioblastoma multiforme (GBM). 1-(2-Chlorethyl)-cyclohexyl-nitrosourea (CCNU, lomustine) monotherapy is an approved chemotherapeutical option for recurrent GBM. Recent evidence demonstrated a survival benefit of combined treatment with BEV and CCNU in patients with a first recurrence of GBM. We examined the outcome of recurrent GBM patients with BEV monotherapy versus BEV/CCNU therapy when used as last-line therapy. 35 patients with recurrent GBM treated between 2010 and 2014 were included in this retrospective study. Progression-free and overall survival was determined with reference to the beginning of BEV or BEV/CCNU therapy and initial diagnosis. 17 patients received BEV monotherapy, 18 patients received combined BEV and CCNU therapy. The impact of parameters such as IDH mutation, MGMT promoter methylation, tumor localization, histology and the number of surgeries were included in a multivariate ANOVA analysis. Furthermore, Karnofsky performance score (KPS), neurological function and toxicity were assessed. BEV/CCNU treatment led to an extension of PFS (6.11 months; 95% CL 3.41-12.98 months; log-rank p = 0.00241) and OS (6.59 months; 95% CL 5.51-16.3 months; log-rank p = 0.0238) of 2 months compared to BEV monotherapy. This survival advantage was independent of histology, IDH mutation status or the number of previous surgeries. Neurological function, KPS and toxicity were not significantly different between both treatment groups. Last-line therapy with BEV/CCNU results in a longer PFS and OS compared to BEV monotherapy and is well-tolerated. These findings confirm the role of these agents in the treatment of recurrent GBM and are in line with other studies.

Novel targeted agents for the treatment of lung cancer in China

Since the discovery of epidermal growth factor receptor mutations and epidermal growth factor receptor tyrosine kinase inhibitors, lung cancer treatment in China has entered the precision era. However, novel targeted agents based on novel biomarkers still need to be developed. In the current study, the authors review the biomarker features of lung cancer in the Chinese population and the novel agents that are aimed at novel targets. Furthermore, they discuss issues that require improvement for the production of novel drugs and provided future directions for development in China.