Humanized anti-hepatocyte growth factor (HGF) antibody suppresses innate irinotecan (CPT-11) resistance induced by fibroblast-derived HGF

Role of cancer-associated fibroblasts in colorectal cancer and their potential as therapeutic targets

Cancer-associated fibroblasts (CAFs) are mesenchymal cells in the tumor microenvironment (TME). CAFs are the most abundant cellular components in the TME of solid tumors. They affect the progression and course of chemotherapy and radiotherapy in various types of tumors including colorectal cancer (CRC). CAFs can promote tumor proliferation, invasion, and metastasis; protect tumor cells from immune surveillance; and resist tumor cell apoptosis caused by chemotherapy, resulting in drug resistance to chemotherapy. In recent years, researchers have become increasingly interested CAF functions and have conducted extensive research. However, compared to other types of malignancies, our understanding of the interaction between CRC cells and CAFs remains limited. Therefore, we searched the relevant literature published in the past 10 years, and reviewed the origin, biological characteristics, heterogeneity, role in the TME, and potential therapeutic targets of CAFs, to aid future research on CAFs and tumors.

Role of cancer-associated fibroblasts in colorectal cancer

Colorectal cancer (CRC) is a malignancy that has a high incidence in all countries around the world. Cancer-associated fibroblasts (CAFs) are a vital component of the tumor microenvironment (TME), playing an important role in the development of CRC. CAFs can release multiple cytokines and exosomes, activating a variety of related signaling pathways and boosting the processes of the invasion, metastasis, metabolism, drug resistance, and immunosuppression in CRC. Thus, CAFs are a prognostic marker and therapeutic target for CRC. Understanding the role and mechanism of CAFs can provide new insights for the treatment of CRC.

Role of cancer-associated fibroblasts in colorectal cancer

Colorectal cancer (CRC) is a malignancy that has a high incidence in all countries around the world. Cancer-associated fibroblasts (CAFs) are a vital component of the tumor microenvironment (TME), playing an important role in the development of CRC. CAFs can release multiple cytokines and exosomes, activating a variety of related signaling pathways and boosting the processes of the invasion, metastasis, metabolism, drug resistance, and immunosuppression in CRC. Thus, CAFs are a prognostic marker and therapeutic target for CRC. Understanding the role and mechanism of CAFs can provide new insights for the treatment of CRC.

Case report: Savolitinib induced severe adverse reactions resembling septic shock in an HIV-1-positive patient with advanced non-small cell lung cancer

Savolitinib, a small-molecule inhibitor of the receptor tyrosine kinase mesenchymal-epithelial transition (MET) factor, was approved for the treatment of non-small cell lung cancer (NSCLC) by the China National Medical Products Administration in June 2021. Its safety for NSCLC treatment has been confirmed in several prospective cohort studies. Herein, we report a rare case of shock, a serious adverse event, after treatment with savolitinib in an HIV-1-positive patient with advanced NSCLC. A 38-year-old man with an 8-year history of HIV-1 positivity was diagnosed with NSCLC 5 years ago; the lung cancer recurred after surgical resection. Despite chemotherapy, immunotherapy, and targeted therapy, tumor progression continued. He received savolitinib because of MET amplification. In the first 2 weeks of savolitinib use, he developed a mild rash on his trunk. In the following month, he was hospitalized for fever and circulatory shock thrice after taking savolitinib 400 mg. He had no urticaria or eosinophilia. During the three hospitalizations, he was negative for pathogens. His condition gradually improved after treatment with antibiotics, steroids, and vasopressors. Attention should be paid to the occurrence of septic shock-like presentations when using savolitinib in HIV-1 patients with NSCLC.

Therapeutic Strategies for Ovarian Cancer in Point of HGF/c-MET Targeting

Ovarian cancer is the fifth leading cause of cancer deaths in women and is regarded as one of the most difficult cancers to treat. Currently, studies are being conducted to develop therapeutic agents for effective treatment of ovarian cancer. In this review, we explain the properties of the hepatocyte growth factor (HGF)/mesenchymal-epithelial transition factor (c-MET) and how the signaling pathway of HGF/c-MET is activated in different cancers and involved in tumorigenesis and metastasis of ovarian cancer. We present the findings of clinical studies using small chemicals or antibodies targeting HGF/c-MET signaling in various cancer types, particularly in ovarian cancer. We also discuss that HGF/c-MET-targeted therapy, when combined with chemo drugs, could be an effective strategy for ovarian cancer therapeutics.

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.

First-in-human phase I trial of anti-hepatocyte growth factor antibody (YYB101) in refractory solid tumor patients

Background

YYB101, a humanized monoclonal antibody against hepatocyte growth factor (HGF), has shown safety and efficacy in vitro and in vivo. This is a first-in-human trial of this antibody.

Materials and Methods

YYB101 was administered intravenously to refractory cancer patients once every 4 weeks for 1 month, and then once every 2 weeks until disease progression or intolerable toxicity, at doses of 0.3, 1, 3, 5, 10, 20, 30 mg/kg, according to a 3+3 dose escalation design. Maximum tolerated dose, safety, pharmacokinetics, and pharmacodynamics were studied. HGF, MET, PD-L1, and ERK expression was evaluated for 9 of 17 patients of the expansion cohort (20 mg/kg).

Results

In 39 patients enrolled, no dose-limiting toxicity was observed at 0.3 mg/kg, and the most commonly detected toxicity was generalized edema (n = 7, 18.9%) followed by pruritis and nausea (n = 5, 13.5%, each), fatigue, anemia, and decreased appetite (n = 4, 10.8%, each). No patient discontinued treatment because of adverse events. YYB101 showed dose-proportional pharmacokinetics up to 30 mg/kg. Partial response in 1 (2.5%) and stable disease in 17 (43.5%) were observed. HGF, MET, PD-L1, and ERK proteins were not significant predictors for treatment response. However, serum HGF level was significantly lowered in responders upon drug administration. RNA sequencing revealed a mesenchymal signature in two long-term responders.

Conclusion

YYB101 showed favorable safety and efficacy in patients with refractory solid tumors. Based on this phase I trial, a phase II study on the YYB101 + irinotecan combination in refractory metastatic colorectal cancer patients is planned.

Conclusion

ClinicalTrials.gov Identifier: NCT02499224.

Humanized Anti-hepatocyte Growth Factor Monoclonal Antibody (YYB-101) Inhibits Ovarian Cancer Progression

Current chemotherapy regimens have certain limitations in improving the survival rates of patients with advanced ovarian cancer. Hepatocyte growth factor (HGF) is important in ovarian cancer cell migration and invasion. This study assessed the effects of YYB-101, a humanized monoclonal anti-HGF antibody, on the growth and metastasis of ovarian cancer cells. YYB-101 suppressed the phosphorylation of the HGF receptor c-MET and inhibited the migration and invasion of SKOV3 and A2780 ovarian cancer cells. Moreover, the combination of YYB-101 and paclitaxel synergistically inhibited tumor growth in an in vivo ovarian cancer mouse xenograft model and significantly increased the overall survival (OS) rate compared with either paclitaxel or YYB-101 alone. Taken together, these findings suggest that YYB-101 has therapeutic potential in ovarian cancer when combined with conventional chemotherapy agents.

Replication Study: Wnt activity defines colon cancer stem cells and is regulated by the microenvironment

As part of the Reproducibility Project: Cancer Biology we published a Registered Report (Evans et al., 2015), that described how we intended to replicate selected experiments from the paper 'Wnt activity defines colon cancer stem cells and is regulated by the microenvironment' (Vermeulen et al., 2010). Here, we report the results. Using three independent primary spheroidal colon cancer cultures that expressed a Wnt reporter construct we observed high Wnt activity was associated with the cell surface markers CD133, CD166, and CD29, but not CD24 and CD44, while the original study found all five markers were correlated with high Wnt activity (Figure 2F; Vermeulen et al., 2010). Clonogenicity was highest in cells with high Wnt activity and clonogenic potential of cells with low Wnt activity were increased by myofibroblast-secreted factors, including HGF. While the effects were in the same direction as the original study (Figure 6D; Vermeulen et al., 2010) whether statistical significance was reached among the different conditions varied. When tested in vivo, we did not find a difference in tumorigenicity between high and low Wnt activity, while the original study found cells with high Wnt activity were more effective in inducing tumors (Figure 7E; Vermeulen et al., 2010). Tumorigenicity, however, was increased with myofibroblast-secreted factors, which was in the same direction as the original study (Figure 7E; Vermeulen et al., 2010), but not statistically significant. Finally, we report meta-analyses for each results where possible.

Role of HGF/c-Met in the treatment of colorectal cancer with liver metastasis

The system of hepatocyte growth factor (HGF) and its receptor c-Met plays a critical role in tumor invasive growth and metastasis. The mortality rate of colorectal cancer (CRC), one of the most commonly diagnosed malignancies, is increased by it gradual development into metastasis, most frequently in the liver. Overexpression of c-Met, the protein tyrosine kinase receptor for the HCF/scatter factor, has been implicated in the progression and metastasis of human colorectal carcinoma. In this study, we aimed to investigate the role of c-Met in CRC liver metastasis and illustrate the clinical impact of regulating HGF/c-Met signaling in patients with CRC liver metastasis. We found that (I) higher levels of c-Met expression (mRNA and Protein) in CRC liver metastasis than primary CRC by assessing the patient tissue samples; (II) a positive correlation of c-Met expression with tumor stages of CRC liver metastasis, as well as c-Met expression in CRC, live metastasis concurred with regional lymph node metastasis; (III) the clinical impact of downregulation of HGF/c-Met signaling on the reduction of proliferation and invasion in CRC liver metastasis. Therefore, we demonstrate that the regulation of HGF/c-Met pathways may be a promising strategy in the treatment of patients with CRC liver metastasis.

Targeting c-met receptor tyrosine kinase by the DNA aptamer SL1 as a potential novel therapeutic option for myeloma

Hepatocyte growth factor (HGF)/c‐met pathway activation has been implicated in the pathogenesis of multiple myeloma (MM), and blocking this pathway has been considered a rational therapeutic strategy for treating MM. Aptamers are single‐stranded nucleic acid molecules that fold into complex 3D structures and bind to a variety of targets. Recently, it was reported that DNA aptamer SL1 exhibited high specificity and affinity for c‐met and inhibited HGF/c‐met signaling in SNU‐5 cells. However, as the first c‐met‐targeted DNA aptamer to be identified, application of SL1 to myeloma treatment requires further investigation. Here, we explore the potential application of SL1 in MM. Our results indicated that c‐met expression is gradually increased in MM patients and contributes to poor outcomes. SL1 selectively bound to c‐met‐positive MM cells but not to normal B cells and suppressed the growth, migration and adhesion of MM cells in vitro in a co‐culture model performed with HS5 cells, wherein SL1 inhibited HGF‐induced activation of c‐met signaling. In vivo and ex vivo fluorescence imaging showed that SL1 accumulated in the c‐met positive tumour areas. In addition, SL1 was active against CD138+ primary MM cells and displayed a synergistic inhibition effect with bortezomib. Collectively, our data suggested that SL1 could be beneficial as a c‐met targeted antagonist in MM.

Status of Agents Targeting the HGF/c-Met Axis in Lung Cancer

Hepatocyte growth factor (HGF) is the ligand for the tyrosine kinase receptor c-Met (Mesenchymal Epithelial Transition Factor also known as Hepatocyte Growth Factor Receptor, HGFR), a receptor with expression throughout epithelial and endothelial cell types. Activation of c-Met enhances cell proliferation, invasion, survival, angiogenesis, and motility. The c-Met pathway also stimulates tissue repair in normal cells. A body of past research shows that increased levels of HGF and/or overexpression of c-Met are associated with poor prognosis in several solid tumors, including lung cancer, as well as cancers of the head and neck, gastro-intestinal tract, breast, ovary and cervix. The HGF/c-Met signaling network is complex; both ligand-dependent and ligand-independent signaling occur. This article will provide an update on signaling through the HGF/c-Met axis, the mechanism of action of HGF/c-Met inhibitors, the lung cancer patient populations most likely to benefit, and possible mechanisms of resistance to these inhibitors. Although c-Met as a target in non-small cell lung cancer (NSCLC) showed promise based on preclinical data, clinical responses in NSCLC patients have been disappointing in the absence of MET mutation or MET gene amplification. New therapeutics that selectively target c-Met or HGF, or that target c-Met and a wider spectrum of interacting tyrosine kinases, will be discussed.

C-MET inhibitors for advanced non-small cell lung cancer

INTRODUCTION

The role of the c-mesenchymal-epithelial transition factor (c-MET) signaling pathway in tumor progression and invasion has been extensively studied. C-MET inhibitors have shown anti-tumor activity in NSCLC both in preclinical and in clinical trials. However, given the molecular heterogeneity of NSCLC, it is likely that only a specific subset of NSCLC patients will benefit from c-MET inhibitors. Emerging data also suggest that MET inhibitors in combination with EGFR-TKIs (epidermal growth factor receptor tyrosine kinase inhibitors) may have a role in therapy for both EGFR-TKI resistant and EGFR-TKI naïve patients. The challenges ahead are in the identification of the molecular subtypes that benefit most.

AREAS COVERED

This review summarizes the current understanding of c-MET biology in relation to studies evaluating c-MET inhibitors in the treatment of NSCLC.

EXPERT OPINION

MET inhibitors have the potential to benefit subsets of NSCLC patients with specific genetic alterations. Exon-14 skipping mutations appear so far to be the most promising molecular subset that is sensitive to MET inhibitors, whereas overexpression, amplification and point mutations of MET seem more challenging subgroups to target. Combination with other target agents, such as EGFR inhibitors, may represent a promising therapeutic strategy in specific areas (e.g. EGFR-TKI resistance).

Hepatocyte growth factor produced in lung fibroblasts enhances non-small cell lung cancer cell survival and tumor progression

Background

The influence of lung fibroblasts on lung cancer progression is not fully understood.

Methods

Lung fibroblasts (HFL1, MRC5, and IMR90 cells) and non-small cell lung cancer (NSCLC)-derived cell lines (A549, EBC1, and HI1017) were cultured under serum-free conditions, and the resulting culture media were designated “cell-conditioned media”. Cell survival (viability) was assessed by WST-1 assay. Concentrations of hepatocyte growth factor (HGF) were measured by ELISA. The BALB/c-nu mouse strain was used for the xenograft model.

Results

Lung fibroblast-conditioned media enhanced the survival of the three NSCLC cell lines tested. HGF was produced to a greater extent by lung fibroblasts than NSCLC cells. Exogenous HGF enhanced the survival of NSCLC cells. Either an anti-HGF neutralizing antibody or the Met inhibitor PHA-665752 inhibited the fibroblast-conditioned media-enhanced survival of NSCLC cells. The co-inoculation of mice with NSCLC cells and fibroblasts enhanced tumorigenicity and tumor progression in a mouse xenograft model. PHA-665752 significantly inhibited tumor progression that occurred after the co-inoculation of NSCLC cells and fibroblasts. In addition, HGF production by fibroblasts was stimulated by NSCLC cells.

Conclusions

The current study provides evidence for an interaction between fibroblasts and NSCLC cells via the HGF/Met signaling pathway, which affects NSCLC cell survival and tumor progression. These findings may contribute to the development of anti-cancer-associated fibroblast therapeutic strategies.

Trial registration

No trial registration is required because this study is not a clinical trial. This study does not include any participants or patients.

Preclinical development of a humanized neutralizing antibody targeting HGF

Hepatocyte growth factor (HGF) and its receptor, cMET, play critical roles in cell proliferation, angiogenesis and invasion in a wide variety of cancers. We therefore examined the anti-tumor activity of the humanized monoclonal anti-HGF antibody, YYB-101, in nude mice bearing human glioblastoma xenografts as a single agent or in combination with temozolomide. HGF neutralization, The extracellular signal-related kinases 1 and 2 (ERK1/2) phosphorylation, and HGF-induced scattering were assessed in HGF-expressing cell lines treated with YYB-101. To support clinical development, we also evaluated the preclinical pharmacokinetics and toxicokinetics in cynomolgus monkeys, and human and cynomolgus monkey tissue was stained with YYB-101 to test tissue cross-reactivity. We found that YYB-101 inhibited cMET activation in vitro and suppressed tumor growth in the orthotopic mouse model of human glioblastoma. Combination treatment with YYB-101 and temozolomide decreased tumor growth and increased overall survival compared with the effects of either agent alone. Five cancer-related genes (TMEM119, FST, RSPO3, ROS1 and NBL1) were overexpressed in YYB-101-treated mice that showed tumor regrowth. In the tissue cross-reactivity assay, critical cross-reactivity was not observed. The terminal elimination half-life was 21.7 days. Taken together, the in vitro and in vivo data demonstrated the anti-tumor efficacy of YYB-101, which appeared to be mediated by blocking the HGF/cMET interaction. The preclinical pharmacokinetics, toxicokinetics and tissue cross-reactivity data support the clinical development of YYB-101 for advanced cancer.

Progress of antibody-based inhibitors of the HGF-cMET axis in cancer therapy

Dysregulated receptor tyrosine kinase signaling in human cancer cells leads to tumor progression, invasion and metastasis. The receptor tyrosine kinase cMET is frequently overexpressed in cancer tissue, and activation of cMET signaling is related to drug resistance and the processes of carcinogenesis, invasion and metastasis. For that reason, cMET and its ligand, hepatocyte growth factor (HGF), are considered prime targets for the development of anticancer drugs. At least eight anti-cMET and four anti-HGF antibodies have been tested or are being tested in clinical trials. However, to date none of these HGF/cMET inhibitors have shown significant efficacy in clinical trials. Furthermore, no receptor tyrosine kinase inhibitors primarily targeting cMET have been approved. Given that neutralization of HGF or cMET does not cause significant adverse effects, inhibition of the HGF/cMET signaling pathway appears to be safe. In this review, we summarized the completed and ongoing clinical trials testing antibody- or protein-based anticancer drugs targeting cMET and HGF.

Determinants of metastatic competency in colorectal cancer

Colorectal cancer (CRC) is one of the most common cancer types and represents a major therapeutic challenge. Although initial events in colorectal carcinogenesis are relatively well characterized and treatment for early‐stage disease has significantly improved over the last decades, the mechanisms underlying metastasis – the main cause of death – remain poorly understood. Correspondingly, no effective therapy is currently available for advanced or metastatic disease. There is increasing evidence that colorectal cancer is hierarchically organized and sustained by cancer stem cells, in concert with various stromal cell types. Here, we review the interplay between cancer stem cells and their microenvironment in promoting metastasis and discuss recent insights relating to both patient prognosis and novel targeted treatment strategies. A better understanding of these topics may aid the prevention or reduction of metastatic burden.