Angiogenesis inhibition in the second-line treatment of metastatic colorectal cancer: A systematic review and pooled analysis

A systemic review and meta-analysis of Aflibercept plus FOLFIRI regimen as a second-line treatment for metastatic colorectal cancer: A PRISMA compliant pooled analysis of randomized controlled trials and single arm studies to assess efficacy and safety

BACKGROUND AND OBJECTIVE

Aflibercept; a decoy receptor for vascular endothelial growth factors (VEGFs) and placental growth factor (PLGF), in combination with FOLFIRI (leucovorin calcium, fluorouracil, irinotecan hydrochloride) chemotherapy regime, was FDA approved in 2012 as second-line salvage chemotherapy for metastatic colorectal cancer (mCRC). This is the first systematic review, and meta-analysis-based evidence to determine the efficacy and safety of Aflibercept plus FOLFIRI regimen pooling randomized controlled trials and single-arm studies.

METHOD

PubMed, Cochrane library, Embase, and Clinical trial.gov were systematically searched for published randomized controlled trials, single-arm studies, and national patient programs on aflibercept plus FOLFIRI chemotherapy for the treatment of mCRC till 11/10/2022.

RESULT

Ten studies met the inclusion criteria comprising 1075 patients for efficacy studies and 2027 patients for safety studies. The pooled prevalences were 18% (95% CI, 5%-37%, p = 0.00) for 12m PFS and 61% (95% CI, 53% - 68%, p = 0.00) for 12m OS. The pooled prevalences were 69% (95% CI, 55% - 82%, p = 0.00) for any grade 3-4 toxicities, 10% (95% CI, 5% - 16%, p = 0.00) for grade 3-4 diarrhea, 13% (95% CI, 5% - 24%, p = 0.00) for grade 3-4 hypertension, 31% (95% CI, 22% - 40%, p = 0.00) for grade 3-4 neutropenia and 5% (95% CI, 2% - 7%, p = 0.00) for grade 3-4 venous thromboembolic event.

CONCLUSION

Our meta-analysis shows that the aflibercept plus FOLFIRI combination shows better survival efficacies however; it is also associated with more high-grade adverse events.

New developments in targeted therapy for metastatic colorectal cancer

Colorectal cancer (CRC) is the second most lethal cancer worldwide and the prognosis of metastatic CRC (mCRC) remains poor. Recent advancements in translational research have led to the identification of several new therapeutic targets and improved the treatment outcome of patients with tumours harbouring BRAF V600E mutation, (HER2) ErBB2 alterations, NTRK gene fusions and KRAS(G12C) mutation. Improved understanding towards the mechanism of resistance to targeted therapy such as anti-epidermal growth factor receptor antibodies and the evolving role of therapeutic monitoring with circulating tumour DNA (ctDNA) has enabled the longitudinal tracking of clonal evolution during treatment and the individualization of subsequent treatments. To broaden the community-based implementation of precision oncology in directing targeted therapies for patients with gastrointestinal cancers including mCRC, the feasibility of 'Master Protocols' that utilizes ctDNA-based genotyping platforms is currently being evaluated. Such protocols encompass both observational and interventional clinical trials of novel targeted therapies conducted within a large clinical trial network. In this review, we will discuss the latest developments in targeted therapies, and therapeutic strategies for overcoming acquired drug resistance in patients with mCRC.

Licoflavone A Suppresses Gastric Cancer Growth and Metastasis by Blocking the VEGFR-2 Signaling Pathway

Objectives

Licoflavone A (LA) is a natural flavonoid compound derived from the root of Glycyrrhiza. This study investigated the antitumor effect and underlying molecular mechanisms of LA against gastric cancer (GC) in vitro and in vivo.

Materials and Methods

A CCK8 assay was used to measure the antiproliferative activity of LA in human GC SGC-7901, MKN-45, MGC-803 cells, and human GES-1 cells. Target prediction and protein-protein interaction (PPI) analysis were used to identify the potential molecular targets of LA. The binding pattern of LA to VEGFR-2 was analyzed by molecular docking and molecular dynamic (MD). The affinity of LA for VEGFR-2 was determined by microscale thermophoresis (MST). The protein tyrosine kinase activity of VEGFR-2 in the presence of LA was determined by an enzyme activity test. The effect of LA on the proliferation of VEGF-stimulated MKN-45 cells was measured with CCK8 assays, clone formation assays, and 3D microsphere models. Hoechst 33342 staining, FCM, MMP, and WB assays were used to investigate the ability of LA to block cell cycle and promote apoptosis of VEGF-stimulated MKN-45 cells. Transwell matrix assays were used to measure migration and invasion, and WB assays were used to measure EMT.

Results

LA inhibited the proliferation of SGC-7901, MKN-45, and MGC-803 cells and VEGF-stimulated MKN-45 cells. VEGFR-2 was identified as the target of LA. LA could also block cell cycle, induce apoptosis, and inhibit migration, invasion, and EMT of VEGF-stimulated MKN-45 cells. Functional analyses further revealed that the cytotoxic effect of LA on VEGF-stimulated MKN-45 cells potentially involved the PI3K/AKT and MEK/ERK signaling pathways.

Conclusions

This study demonstrates that LA has anti-GC potency in vitro and in vivo. LA affects the proliferation, cycle, apoptosis, migration, invasion, and EMT by targeting VEGFR-2 and blocks the PI3K/AKT and MEK/ERK signaling pathways in VEGF-stimulated MKN-45 cells.

Evidence-Based Second-Line Treatment in RAS Wild-Type/Mutated Metastatic Colorectal Cancer in the Precision Medicine Era

Target-oriented agents improve metastatic colorectal cancer (mCRC) survival in combination with chemotherapy. However, the majority of patients experience disease progression after first-line treatment and are eligible for second-line approaches. In such a context, antiangiogenic and anti-Epidermal Growth Factor Receptor (EGFR) agents as well as immune checkpoint inhibitors have been approved as second-line options, and RAS and BRAF mutations and microsatellite status represent the molecular drivers that guide therapeutic choices. Patients harboring K- and N-RAS mutations are not eligible for anti-EGFR treatments, and bevacizumab is the only antiangiogenic agent that improves survival in combination with chemotherapy in first-line, regardless of RAS mutational status. Thus, the choice of an appropriate therapy after the progression to a bevacizumab or an EGFR-based first-line treatment should be evaluated according to the patient and disease characteristics and treatment aims. The continuation of bevacizumab beyond progression or its substitution with another anti-angiogenic agents has been shown to increase survival, whereas anti-EGFR monoclonals represent an option in RAS wild-type patients. In addition, specific molecular subgroups, such as BRAF-mutated and Microsatellite Instability-High (MSI-H) mCRCs represent aggressive malignancies that are poorly responsive to standard therapies and deserve targeted approaches. This review provides a critical overview about the state of the art in mCRC second-line treatment and discusses sequential strategies according to key molecular biomarkers.

An appraisal of emerging second line therapies for metastatic colorectal cancer

INTRODUCTION

Despite a significant improvement in overall survival over the last 15 years, colorectal cancer remains a major public health problem worldwide. Much effort has been made to develop an optimal choice of first-line treatments, but after progression the therapeutic possibilities and the criteria for choice are different.

AREAS COVERED

The purpose of this literature review is to discuss the different possibilities of second-line treatment and to specify the criteria for choice. Biological subgroups requiring specific therapeutic decisions will be described. We conducted a systematic review for randomized controlled trials published since 1995. A non-exhaustive review of published phase II studies, cohort studies, and international guidelines was also given and future leads were discussed.

EXPERT OPINION

Some choices of second-line treatments are a direct result of the option chosen in the first line. Others are necessary because of the biological specificity of the tumor: immunotherapy for tumors with microsatellite instability, or the combination encorafenib cetuximab for mutated BRAF-V600E tumors. In many other circumstances, there are several options that require extensive involvement of multidisciplinary boards and the patient in the final therapeutic decision.

Different administration methods of endostar combined with second-line chemotherapy in advanced malignancies

Background

This study aimed to compare the therapeutic efficacy and the side effects of different endostar administration methods in patients with advanced malignancy who underwent second-line chemotherapy.

Methods

98 patients with advanced malignancies were divided into 2 groups based on the delivery methods of endostar, including drip intravenous administration of endostar (DE) group and continuous intravenous administration of endostar (CE) group. Response rate (RR), disease control rate (DCR), and quality of life (QOL) of the patients were examined to evaluate the therapeutic efficacy, and toxicity reactions were analyzed to evaluate the adverse effects.

Results

Compared with the DE group, the therapeutic efficacy of CE has been slightly improved, but the difference did not reach statistical significance (P > 0.05). Additionally, no different incidence rate was observed in toxic reactions, including leukopenia, thrombocytopenia, nausea and vomiting, diarrhea, and hepatic function damage, between the DE and CE groups (P > 0.05).

Conclusion

In conclusion, no significant difference was observed between the traditional intravenous drip of endostar group and the intravenous drip followed by continuous pumping of endostar group in the patients with advanced malignancies.

Existing anti-angiogenic therapeutic strategies for patients with metastatic colorectal cancer progressing following first-line bevacizumab-based therapy

Continuous inhibition of angiogenesis beyond progression is an emerging treatment concept in the management of metastatic colorectal cancer patients with prior bevacizumab exposure. Treatment options include the continuation or reintroduction of bevacizumab during the second-line chemotherapy or switching to a different antiangiogenic monoclonal antibody such as aflibercept or ramucirumab. In the selection of treatment, patient-based factors such as performance status, age, tumor burden, and tolerance and sensitivity to the first-line bevacizumab-based therapy, as well as treatment-related factors such as toxicity, efficacy, and cost, should be taken into consideration.

Autophagy Inhibition Promotes Bevacizumab-induced Apoptosis and Proliferation Inhibition in Colorectal Cancer Cells

Aim: Anti-VEGF therapy plays an important role in the treatment of malignant tumors, especially metastatic malignant tumors. However, resistance and an inefficient response to anti-VEGF therapy exist. The current study aimed to investigate whether autophagy plays a part in the anti-tumor effect of bevacizumab in colorectal cancer cells. Methods: VEGF-A expression was measured by immunohistochemical methods. Cell viability and cell apoptosis were detected using 3-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT) and flow cytometry. Autophagy was assessed by a western blot, fluorescence microscopy and transmission electron microscopy. HIF-1α was measured using a western blot. A xenograft tumor model of colorectal cancer was constructed to determine the efficacy of the treatment of bevacizumab and chloroquine. Results: VEGF-A protein was upregulated in colorectal cancer tissue. Anti-VEGF (bevacizumab) inhibited cell viability and induced apoptosis. Moreover, bevacizumab induced autophagy. The inhibition of autophagy by chloroquine or by small interfering RNA promoted bevacizumab-induced apoptosis and proliferation inhibition. Further study showed that bevacizumab treatment significantly augmented HIF-1α. Furthermore, cells pretreated with YC-1, a HIF-1α inhibitor, displayed significantly attenuated bevacizumab-induced autophagy. Finally, a combinatory treatment of bevacizumab and chloroquine synergistically inhibited tumor growth in a xenograft tumor model of colorectal cancer cells. Conclusions: Our results showed that the inhibition of autophagy promoted the anti-tumor effect of bevacizumab and may offer a promising therapeutic strategy for colorectal cancer.

CIMAvax-EGF: Toward long-term survival of advanced NSCLC

Lung cancer remains one of the leading causes of cancer-related deaths. Non-small cell lung cancer (NSCLC) is the most common histologic type of lung cancer. Medical and scientific progress has led to longer survival in an increasing number of patients suffering from cancer. Concerning patients with advanced NSCLC, there is a subgroup with long-term survival. The human epidermal growth factor receptor (EGFR) family plays a key role in tumor development. This cluster of genes is associated with augmented angiogenesis and enhanced proliferation, survival, and migration of tumor cells. The CIMAvax-EGF vaccine consists of a chemical conjugate of the EGF with the P64 protein derived from the Meningitis B bacteria and the Montanide ISA 51, as adjuvant. The vaccine induces antibodies against EGF that results in EGF withdrawal. CIMAvax-EGF has been demonstrated to be safe and immunogenic in advanced NSCLC patients. Here we summarize the current knowledge of the mechanism of action of CIMAvax-EGF, highlighting the impact of this anti-EGF-based vaccine on the long-term survival of advanced NSCLC patients.