Function of the c-Met receptor tyrosine kinase in carcinogenesis and associated therapeutic opportunities

Targeting the hedgehog pathway in MET mutation cancers and its effects on cells associated with cancer development

The mutation of MET plays a crucial role in the initiation of cancer, while the Hedgehog (Hh) pathway also plays a significant role in cell differentiation and the maintenance of tumor stem cells. Conventional chemotherapy drugs are primarily designed to target the majority of cell populations within tumors rather than tumor stem cells. Consequently, after a brief period of remission, tumors often relapse. Moreover, the exclusive targeting of tumor stemness cell disregards the potential for other tumor cells to regain stemness and acquire drug resistance. As a result, current drugs that solely target the HGF/c-MET axis and the Hh pathway demonstrate only moderate efficacy in specific types of cancer. Mounting evidence indicates that these two pathways not only play important roles in cancer but also exert significant influence on the development of resistance to single-target therapies through the secretion of their own ligands. In this comprehensive review, we analyze and compare the potential impact of the Hh pathway on the tumor microenvironment (TME) in HGF/c-MET-driven tumor models, as well as the interplay between different cell types. Additionally, we further substantiate the potential and necessity of dual-pathway combination therapy as a critical target in MET addicted cancer treatment. Video Abstract.

Imidazopyridine-based kinase inhibitors as potential anticancer agents: A review

Considering the fundamental role of protein kinases in the mechanism of protein phosphorylation in critical cellular processes, their dysregulation, especially in cancers, has underscored their therapeutic relevance. Imidazopyridines represent versatile scaffolds found in abundant bioactive compounds. Given their structural features, imidazopyridines have possessed pivotal potency to interact with different protein kinases, inspiring researchers to carry out numerous structural variations. In this comprehensive review, we encompass an extensive survey of the design and biological evaluations of imidazopyridine-based small molecules as potential agents targeting diverse kinases for anticancer applications. We describe the structural elements critical to inhibitory potency, elucidating their key structure-activity relationships (SAR) and mode of actions, where available. We classify these compounds into two groups: Serine/threonine and Tyrosine inhibitors. By highlighting the promising role of imidazopyridines in kinase inhibition, we aim to facilitate the design and development of more effective, targeted compounds for cancer treatment.

SMYD3 Modulates the HGF/MET Signaling Pathway in Gastric Cancer

Gastric cancer (GC) is the third most deadly cancer worldwide. Considerable efforts have been made to find targetable drivers in order to improve patient outcomes. MET is one of the most important factors involved in GC initiation and progression as it plays a major role in GC invasiveness and is related to cancer stemness. Unfortunately, treatment strategies targeting MET are still limited, with a proportion of patients responding to therapy but later developing resistance. Here, we showed that MET is a molecular partner of the SMYD3 methyltransferase in GC cells. Moreover, we found that SMYD3 pharmacological inhibition affects the HGF/MET downstream signaling pathway. Extensive cellular analyses in GC models indicated that EM127, a novel active site-selective covalent SMYD3 inhibitor, can be used as part of a synergistic approach with MET inhibitors in order to enhance the targeting of the HGF/MET pathway. Importantly, our data were confirmed in a 3D GC cell culture system, which was used as a surrogate to evaluate stemness characteristics. Our findings identify SMYD3 as a promising therapeutic target to impair the HGF/MET pathway for the treatment of GC.

LIMS-Kinase provides sensitive and generalizable label-free in vitro measurement of kinase activity using mass spectrometry

Measurements of kinase activity are important for kinase-directed drug development, analysis of inhibitor structure and function, and understanding mechanisms of drug resistance. Sensitive, accurate, and miniaturized assay methods are crucial for these investigations. Here, we describe a label-free, high-throughput mass spectrometry-based assay for studying individual kinase enzymology and drug discovery in a purified system, with a focus on validated drug targets as benchmarks. We demonstrate that this approach can be adapted to many known kinase substrates and highlight the benefits of using mass spectrometry to measure kinase activity in vitro, including increased sensitivity. We speculate that this approach to measuring kinase activity will be generally applicable across most of the kinome, enabling research on understudied kinases and kinase drug discovery.

Fully automated radiolabeling of [68Ga]Ga-EMP100 targeting c-MET for PET-CT clinical imaging

BACKGROUND

c-MET is a transmembrane receptor involved in many biological processes and contributes to cell proliferation and migration during cancer invasion process. Its expression is measured by immunehistochemistry on tissue biopsy in clinic, although this technique has its limitations. PET-CT could allow in vivo mapping of lesions expressing c-MET, providing whole-body detection. A number of radiopharmaceuticals are under development for this purpose but are not yet in routine clinical use. EMP100 is a cyclic oligopeptide bound to a DOTA chelator, with nanomolar affinity for c-MET. The aim of this project was to develop an automated method for radiolabelling the radiopharmaceutical [68Ga]Ga-EMP100.

RESULTS

The main results showed an optimal pH range between 3.25 and 3.75 for the complexation reaction and a stabilisation of the temperature at 90 °C, resulting in an almost complete incorporation of gallium-68 after 10 min of heating. In these experiments, 90 µg of EMP-100 peptide were initially used and then lower amounts (30, 50, 75 µg) were explored to determine the minimum required for sufficient synthesis yield. Radiolysis impurities were identified by radio-HPLC and ascorbic acid and ethanol were used to improve the purity of the compound. Three batches of [68Ga]Ga-EMP100 were then prepared according to the optimised parameters and all met the established specifications. Finally, the stability of [68Ga]Ga-EMP100 was assessed at room temperature over 3 h with satisfactory results in terms of appearance, pH, radiochemical purity and sterility.

CONCLUSIONS

For the automated synthesis of [68Ga]Ga-EMP100, the parameters of pH, temperature, precursor peptide content and the use of adjuvants for impurity management were efficiently optimised, resulting in the production of three compliant and stable batches according to the principles of good manufacturing practice. [68Ga]Ga-EMP100 was successfully synthesised and is now available for clinical development in PET-CT imaging.

Molecular Basis and Natural History of Medullary Thyroid Cancer: It is (Almost) All in the RET

Medullary thyroid cancer (MTC) is a rare disease, which can be either sporadic (roughly 75% of cases) or genetically determined (multiple endocrine neoplasia type 2, due to REarranged during Transfection RET germline mutations, 25% of cases). Interestingly, RET pathogenic variants (mainly M918T) have also been reported in aggressive forms of sporadic MTC, suggesting the importance of RET signalling pathways in the pathogenesis of MTC. The initial theory of RET codon-related MTC aggressiveness has been recently questioned by studies suggesting that this would only define the age at disease onset rather than the aggressiveness of MTC. Other factors might however impact the natural history of the disease, such as RET polymorphisms, epigenetic factors, environmental factors, MET (mesenchymal-epithelial transition) alterations, or even other genetic alterations such as RAS family (HRAS, KRAS, NRAS) genetic alterations. This review will detail the molecular bases of MTC, focusing on RET pathways, and the potential mechanisms that explain the phenotypic intra- and interfamilial heterogeneity.

Capmatinib‑associated interstitial lung disease in a patient with lung adenocarcinoma harboring a skipping mutation of mesenchymal‑epithelial transition exon 14: A case report

Capmatinib is a medication used to treat patients with non-small cell lung cancer (NSCLC) who have a specific genetic mutation known as a mesenchymal-epithelial transition exon 14 skipping mutation. Previous clinical trials have reported that capmatinib treatment has a high objective response rate in patients with this genetic mutation. However, there have also been rare reports of patients developing interstitial lung disease (ILD) following capmatinib treatment, which can be life-threatening. The present case study reports the treatment of a patient who developed ILD after 6 weeks of capmatinib treatment for NSCLC, which was resolved following application of corticosteroids. The present case demonstrated that early recognition of the onset of ILD and discontinuation of capmatinib treatment, along with the prompt initiation of corticosteroid administration, can lead to complete resolution of ILD.

Targeting Lactate Dehydrogenase-B as a Strategy to Fight Cancer: Identification of Potential Inhibitors by In Silico Analysis and In Vitro Screening

Lactate dehydrogenase (LDH) is an enzyme that catalyzes the reversible conversion of lactate to pyruvate while reducing NAD+ to NADH (or oxidizing NADH to NAD+). Due to its central role in the Warburg effect, LDH-A isoform has been considered a promising target for treating several types of cancer. However, research on inhibitors targeting LDH-B isoform is still limited, despite the enzyme's implication in the development of specific cancer types such as breast and lung cancer. This study aimed to identify small-molecule compounds that specifically inhibit LDH-B. Our in silico analysis identified eight commercially available compounds that may affect LDH-B activity. The best five candidates, namely tucatinib, capmatinib, moxidectin, rifampicin, and acetyldigoxin, were evaluated further in vitro. Our results revealed that two compounds, viz., tucatinib and capmatinib, currently used for treating breast and lung cancer, respectively, could also act as inhibitors of LDH-B. Both compounds inhibited LDH-B activity through an uncompetitive mechanism, as observed in in vitro experiments. Molecular dynamics studies further support these findings. Together, our results suggest that two known drugs currently being used to treat specific cancer types may have a dual effect and target more than one enzyme that facilitates the development of these types of cancers. Furthermore, the results of this study could be used as a new starting point for identifying more potent and specific LDH-B inhibitors.

An Overview of Systemic Targeted Therapy in Renal Cell Carcinoma, with a Focus on Metastatic Renal Cell Carcinoma and Brain Metastases

The most commonly diagnosed malignancy of the urinary system is represented by renal cell carcinoma. Various subvariants of RCC were described, with a clear-cell type prevailing in about 85% of all RCC tumors. Patients with metastases from renal cell carcinoma did not have many effective therapies until the end of the 1980s, as long as hormonal therapy and chemotherapy were the only options available. The outcomes were unsatisfactory due to the poor effectiveness of the available therapeutic options, but then interferon-alpha and interleukin-2 showed treatment effectiveness, providing benefits but only for less than half of the patients. However, it was not until 2004 that targeted therapies emerged, prolonging the survival rate. Currently, new technologies and strategies are being developed to improve the actual efficacy of available treatments and their prognostic aspects. This article summarizes the mechanisms of action, importance, benefits, adverse events of special interest, and efficacy of immunotherapy in metastatic renal cell carcinoma, with a focus on brain metastases.

Off-target pharmacological activity at various kinases: Potential functional and pathological side effects

In drug discovery, during the lead optimization and candidate characterization stages, novel small molecules are frequently evaluated in a battery of in vitro pharmacology assays to identify potential unintended, off-target interactions with various receptors, transporters, ion channels, and enzymes, including kinases. Furthermore, these screening panels may also provide utility at later stages of development to provide a mechanistic understanding of unexpected safety findings. Here, we present a compendium of the most likely functional and pathological outcomes associated with interaction(s) to a panel of 95 kinases based on an extensive curation of the scientific literature. This panel of kinases was designed by AbbVie based on safety-related data extracted from the literature, as well as from over 20 years of institutional knowledge generated from discovery efforts. For each kinase, the scientific literature was reviewed using online databases and the most often reported functional and pathological effects were summarized. This work should serve as a practical guide for small molecule drug discovery scientists and clinical investigators to predict and/or interpret adverse effects related to pharmacological interactions with these kinases.

The role of cancer-associated fibroblasts in bladder cancer progression

Cancer-associated fibroblasts (CAFs) are key stromal cells in the tumor microenvironment (TME) that critically contribute to cancer initiation and progression. In bladder cancer (BCa), there is emerging evidence that BCa CAFs are actively involved in cancer cell proliferation, invasion, metastasis, and chemotherapy resistance. This review outlines the present knowledge of BCa CAFs, with a particular emphasis on their origin and function in BCa progression, and provides further insights into their clinical application.

LncRNA PVT1: as a therapeutic target for breast cancer

A significant number of women are identified with breast cancer (BC) every year, making it among the most prevalent malignancies and one of the leading causes of mortality globally. Despite significant progress in understanding BC pathogenesis and treatment options, there is still a need to identify new therapeutic targets and develop more effective treatments. LncRNAs have been discovered as biomarkers and a promising target for various cancers, including BC. PVT1 is a particular one of these lncRNAs, and research has indicated that it has a significant impact on the appearance and progression of BC.PVT1 is an attractive therapeutic target for BC due to its role in promoting cancer cell growth, metastasis and invasion. In addition to its potential as a treatment strategy, PVT1 may also have diagnostic value in BC. In this article, we will discuss targeting PVT1 as a treatment strategy for BC.

Discovery of a new potent oxindole multi-kinase inhibitor among a series of designed 3-alkenyl-oxindoles with ancillary carbonic anhydrase inhibitory activity as antiproliferative agents

An optimization strategy was adopted for designing and synthesizing new series of 2-oxindole conjugates. Selected compounds were evaluated for their antiproliferative effect in vitro against NCI-60 cell lines panel, inhibitory effect on carbonic anhydrase (CA) isoforms (hCAI, II, IX and XII), and protein kinases. Compounds 5 and 7 showed promising inhibitory effects on hCA XII, whereas compound 4d was the most potent inhibitor with low nanomolar CA inhibition against all tested isoforms. These results were rationalized by using molecular docking. Despite its lack of CA inhibitory activity, compound 15c was the most active antiproliferative candidate against most of the 60 cell lines with mean growth inhibition 61.83% and with IC₅₀ values of 4.39, 1.06, and 0.34 nM against MCT-7, DU 145, and HCT-116 cell lines, respectively. To uncover the mechanism of action behind its antiproliferative activity, compound 15c was assessed against a panel of protein kinases (RET, KIT, cMet, VEGFR1,2, FGFR1, PDFGR and BRAF) showing % inhibition of 74%, 31%, 62%, 40%, 73%, 74%, 59%, and 69%, respectively, and IC₅₀ of 1.287, 0.117 and 1.185 μM against FGFR1, VEGFR, and RET kinases, respectively. These results were also explained through molecular docking.

Distinct shared and compartment-enriched oncogenic networks drive primary versus metastatic breast cancer

Metastatic breast-cancer is a major cause of death in women worldwide, yet the relationship between oncogenic drivers that promote metastatic versus primary cancer is still contentious. To elucidate this relationship in treatment-naive animals, we hereby describe mammary-specific transposon-mutagenesis screens in female mice together with loss-of-function Rb, which is frequently inactivated in breast-cancer. We report gene-centric common insertion-sites (gCIS) that are enriched in primary-tumors, in metastases or shared by both compartments. Shared-gCIS comprise a major MET-RAS network, whereas metastasis-gCIS form three additional hubs: Rho-signaling, Ubiquitination and RNA-processing. Pathway analysis of four clinical cohorts with paired primary-tumors and metastases reveals similar organization in human breast-cancer with subtype-specific shared-drivers (e.g. RB1-loss, TP53-loss, high MET, RAS, ER), primary-enriched (EGFR, TGFβ and STAT3) and metastasis-enriched (RHO, PI3K) oncogenic signaling. Inhibitors of RB1-deficiency or MET plus RHO-signaling cooperate to block cell migration and drive tumor cell-death. Thus, targeting shared- and metastasis- but not primary-enriched derivers offers a rational avenue to prevent metastatic breast-cancer.

The Development and Role of Capmatinib in the Treatment of MET-Dysregulated Non-Small Cell Lung Cancer-A Narrative Review

Non-small cell lung cancer (NSCLC) is a leading cause of death, but over the past decade, there has been tremendous progress in the field with new targeted therapies. The mesenchymal-epithelial transition factor (MET) proto-oncogene has been implicated in multiple solid tumors, including NSCLC, and dysregulation in NSCLC from MET can present most notably as MET exon 14 skipping mutation and amplification. From this, MET tyrosine kinase inhibitors (TKIs) have been developed to treat this dysregulation despite challenges with efficacy and reliable biomarkers. Capmatinib is a Type Ib MET TKI first discovered in 2011 and was FDA approved in August 2022 for advanced NSCLC with MET exon 14 skipping mutation. In this narrative review, we discuss preclinical and early-phase studies that led to the GEOMETRY mono-1 study, which showed beneficial efficacy in MET exon 14 skipping mutations, leading to FDA approval of capmatinib along with Foundation One CDx assay as its companion diagnostic assay. Current and future directions of capmatinib are focused on improving the efficacy, overcoming the resistance of capmatinib, and finding approaches for new indications of capmatinib such as acquired MET amplification from epidermal growth factor receptor (EGFR) TKI resistance. Clinical trials now involve combination therapy with capmatinib, including amivantamab, trametinib, and immunotherapy. Furthermore, new drug agents, particularly antibody-drug conjugates, are being developed to help treat patients with acquired resistance from capmatinib and other TKIs.

ERK Signaling Pathway Is Constitutively Active in NT2D1 Non-Seminoma Cells and Its Inhibition Impairs Basal and HGF-Activated Cell Proliferation

c-MET/hepatocyte growth factor (HGF) system deregulation is a well-known feature of malignancy in several solid tumors, and for this reason this system and its pathway have been considered as potential targets for therapeutic purposes. In previous manuscripts we reported c-MET/HGF expression and the role in testicular germ cell tumors (TGCTs) derived cell lines. We demonstrated the key role of c-Src and phosphatidylinositol 3-kinase (PI3K)/AKT adaptors in the HGF-dependent malignant behavior of the embryonal carcinoma cell line NT2D1, finding that the inhibition of these onco-adaptor proteins abrogates HGF triggered responses such as proliferation, migration, and invasion. Expanding on these previous studies, herein we investigated the role of mitogen-activated protein kinase (MAPK)/extracellular signal regulated kinase (ERK) pathways in the HGF-dependent and HGF-independent NT2D1 cells biological responses. To inhibit MAPK/ERK pathways we chose a pharmacological approach, by using U0126 inhibitor, and we analyzed cell proliferation, collective migration, and chemotaxis. The administration of U0126 together with HGF reverts the HGF-dependent activation of cell proliferation but, surprisingly, does not exert the same effect on NT2D1 cell migration. In addition, we found that the use of U0126 alone significantly promotes the acquisition of NT2D1 «migrating phenotype», while collective migration of NT2D1 cells was stimulated. Notably, the inhibition of ERK activation in the absence of HGF stimulation resulted in the activation of the AKT-mediated pathway, and this let us speculate that the paradoxical effects obtained by using U0126, which are the increase of collective migration and the acquisition of partial epithelium-mesenchyme transition (pEMT), are the result of compensatory pathways activation. These data highlight how the specific response to pathway inhibitors, should be investigated in depth before setting up therapy.

Discovery of novel cMET-targeting antibody Fab drug conjugates as potential treatment for solid tumors with highly expressed cMET

BACKGROUND

Solid tumors are becoming prevalent affecting both old and young populations. Numerous solid tumors are associated with high cMET expression. The complexity of solid tumors combined with the highly interconnected nature of the cMET/HGF pathway with other cellular pathways make the pursuit of finding an effective treatment extremely challenging. The current standard of care for these malignancies is mostly small molecule-based chemotherapy. Antibody-based therapeutics as well as antibody drug conjugates are promising emerging classes against cMET-overexpressing solid tumors.

RESEARCH DESIGN AND METHODS

In this study, we described the design, synthesis, in vitro and in vivo characterization of cMET-targeting Fab drug conjugates (FDCs) as an alternative therapeutic strategy. The format is comprised of a Fab conjugated to a potent cytotoxic drug via a cleavable linker employing lysine-based and cysteine-based conjugation chemistries.

RESULTS

We found that the FDCs have potent anti-tumor efficacies in cancer cells with elevated overexpression of cMET. Moreover, they demonstrated a remarkable anti-tumor effect in a human gastric xenograft mouse model.

CONCLUSIONS

The FDC format has the potential to overcome some of the challenges presented by the other classes of therapeutics. This study highlights the promise of antibody fragment-based drug conjugate formats for the treatment of solid tumors.

HGF/c-Met pathway inhibition combined with chemotherapy increases cytotoxic T-cell infiltration and inhibits pancreatic tumour growth and metastasis

Pancreatic cancer (PC) is a deadly cancer with a high mortality rate. The unique characteristics of PC, including desmoplasia and immunosuppression, have made it difficult to develop effective treatment strategies. Pancreatic stellate cells (PSCs) play a crucial role in the progression of the disease by interacting with cancer cells. One of the key mediators of PSC - cancer cell interactions is the hepatocyte growth factor (HGF)/c-MET pathway. Using an immunocompetent in vivo model of PC as well as in vitro experiments, this study has shown that a combined approach using HGF/c-MET inhibitors to target stromal-tumour interactions and chemotherapy (gemcitabine) to target cancer cells effectively decreases tumour volume, EMT, and stemness, and importantly, eliminates metastasis. Notably, HGF/c-MET inhibition decreases TGF-β secretion by cancer cells, resulting in an increase in cytotoxic T-cell infiltration, thus contributing to cancer cell death in tumours. HGF/c-MET inhibition + chemotherapy was also found to normalise the gut microbiome and improve gut microbial diversity. These findings provide a strong platform for assessment of this triple therapy (HGF/c-MET inhibition + chemotherapy) approach in the clinical setting.

Anticancer Potential of Natural Chalcones: In Vitro and In Vivo Evidence

There is no doubt that significant progress has been made in tumor therapy in the past decades. However, the discovery of new molecules with potential antitumor properties still remains one of the most significant challenges in the field of anticancer therapy. Nature, especially plants, is a rich source of phytochemicals with pleiotropic biological activities. Among a plethora of phytochemicals, chalcones, the bioprecursors of flavonoid and isoflavonoids synthesis in higher plants, have attracted attention due to the broad spectrum of biological activities with potential clinical applications. Regarding the antiproliferative and anticancer effects of chalcones, multiple mechanisms of action including cell cycle arrest, induction of different forms of cell death and modulation of various signaling pathways have been documented. This review summarizes current knowledge related to mechanisms of antiproliferative and anticancer effects of natural chalcones in different types of malignancies including breast cancers, cancers of the gastrointestinal tract, lung cancers, renal and bladder cancers, and melanoma.

Molecular characterization of MET fusions from a large real-world Chinese population: A multicenter study

PURPOSE

MET is a notable driver gene in the diversity of aberrations with clinical relevance, including exon 14 skipping, copy number gain, point mutations, and gene fusions. Compared with the former two, MET fusions are severely under-reported, leaving a series of unanswered questions. In this study, we addressed this gap by characterizing MET fusions in a large, real-world Chinese cancer population.

METHODS

We retrospectively included patients with solid tumors who had DNA-based genome profiles acquired through targeted sequencing from August 2015 to May 2021. MET fusion-positive (MET+) patients were subsequently selected for clinical and molecular characterization.

RESULTS

We screened 79,803 patients across 27 tumor types and detected 155 putative MET fusions from 122 patients, resulting in an overall prevalence of 0.15%. Lung cancer comprised the majority of MET+ patients (92, 75.4%). Prevalence was markedly higher in liver cancer, biliary tract cancer, and renal cancer (range 0.52%-0.60%). It was lower in ovarian cancer (0.06%). A substantial proportion (48/58, 82.8%) of unique partners were reported for the first time. High heterogeneity was observed for partners, with ST7, HLA-DRB1, and KIF5B as the three most common partners. Mutational landscape analysis of lung adenocarcinoma (n = 32) revealed a high prevalence of TP53 in MET+ alterations, EGFR L858R, EGFR L861Q, and MET amplification.

CONCLUSION

To our knowledge, this is currently the largest study in characterizing MET fusions. Our findings warrant that further clinical validation and mechanistic study may translate into therapeutic avenues for MET+ cancer patients.

Oncolytic virotherapy in lung cancer

Lung tumors are one of the most aggressive threats affecting humans. Current therapeutic approaches have improved patients' survival; however, further efforts are required to increase effectiveness and protection against tumor relapse and metastasis. Immunotherapy presents an alternative to previous treatments that focuses on stimulating of the patient's immune system to destroy tumor cells. Viruses can be used as part of the immune therapeutic approach as agents that could selectively infect tumor cells, triggering an immune response against the infection and against the tumor cells. Some viruses have been selected for specifically infecting and destroying cancer cells, activating the immune response, enhancing access, amplifying the cytotoxicity against the tumor cells, and improving the long-term memory that can prevent tumor relapse. Oncolytic virotherapy can then be used as a strategy to target the destruction of transformed cells at the tumor site and act in locations distant from the primary targeted tumor site. Some of the current challenges in lung cancer treatment can be addressed using traditional therapies combined with oncolytic virotherapy. Defining the best combination, including the choice of the right settings will be at the next frontier in lung cancer treatment.

Angiogenic signaling pathways and anti-angiogenic therapy for cancer

Angiogenesis, the formation of new blood vessels, is a complex and dynamic process regulated by various pro- and anti-angiogenic molecules, which plays a crucial role in tumor growth, invasion, and metastasis. With the advances in molecular and cellular biology, various biomolecules such as growth factors, chemokines, and adhesion factors involved in tumor angiogenesis has gradually been elucidated. Targeted therapeutic research based on these molecules has driven anti-angiogenic treatment to become a promising strategy in anti-tumor therapy. The most widely used anti-angiogenic agents include monoclonal antibodies and tyrosine kinase inhibitors (TKIs) targeting vascular endothelial growth factor (VEGF) pathway. However, the clinical benefit of this modality has still been limited due to several defects such as adverse events, acquired drug resistance, tumor recurrence, and lack of validated biomarkers, which impel further research on mechanisms of tumor angiogenesis, the development of multiple drugs and the combination therapy to figure out how to improve the therapeutic efficacy. Here, we broadly summarize various signaling pathways in tumor angiogenesis and discuss the development and current challenges of anti-angiogenic therapy. We also propose several new promising approaches to improve anti-angiogenic efficacy and provide a perspective for the development and research of anti-angiogenic therapy.

Immunohistochemical expression of the hepatocyte growth factor in chromophobe renal cell carcinoma

BACKGROUND

The prognostic value of Hepatocyte growth factor (HGF) in non-clear cell renal cell carcinoma (RCC) is still unclear. The aim of this study is to evaluate the prognostic impact of HGF expression in a large cohort of chromophobe RCC (chRCC).

METHODS

Patients who underwent renal surgery due to chRCC were recruited. Clinical data was retrospectively evaluated. Tumor specimen were analyzed for HGF expression by immunohistochemistry.

RESULTS

81 chRCC patients were eligible for analysis, thereof 37 (45.7%) patients were positive for HGF. No significant associations were found for HGF expression and clinical attributes in patients with chRCC. Kaplan-Meier analysis revealed no differences in 5-year overall survival (OS) for patients with HGF^- compared to HGF⁺ tumors (95.0% versus 90.9%; p = 0.410).

CONCLUSIONS

In chRCC HGF expression is not associated with parameters of aggressiveness or survival.

Quinacrine inhibits cMET-mediated metastasis and angiogenesis in breast cancer stem cells

A trans-membrane receptor tyrosine kinase, cMET, belonging to the MET proto-oncogene family, is responsible for cancer metastasis and angiogenesis. But not much is known about the role of cMET in growth and progression of cancer stem cells (CSCs). Earlier studies have shown that Quinacrine (QC), a bioactive agent, has anti-CSCs activity. Here, the role of QC in deregulation of cMET-mediated metastasis and angiogenesis has been systematically evaluated in vitro in highly metastatic breast CSCs (mBCSCs), ex vivo in patient-derived breast cancer stem cells (PDBCSCs) and in vivo in xenograft mice model systems. Cell proliferation, migration, invasion and representative metastasis markers were upregulated in cMET-overexpressed cells and QC exposure inhibited these processes in both mBCSCs and PDBCSCs. Interestingly, metastasis was significantly inhibited by QC in cMET-overexpressed cells but comparatively lesser significant alteration of the process was noted in cMET-silenced cells. Increase in vascularization (in in ovo CAM assay), and cell-cell tube formation (in HUVECs), and enhanced MMP9 and MMP2 enzymatic activities (in gelatin zymography) were noted after cMET overexpression but these processes got reversed after cMET knockdown or QC treatment in cMET-overexpressed cells. QC inhibited angiogenesis significantly in cMET-overexpressed cells, but lesser significant change was observed in cMET-silenced cells. Reduction in tumor volume and decreased expression of metastatic and angiogenic markers were also noted in xenograft mice after QC treatment. Furthermore, QC inhibited cMET activity by dephosphorylation of its tyrosine residues (Y1234 and Y1356) and downregulation of its downstream cascade. Thus, QC inhibited the cMET-mediated metastasis and angiogenesis in in vitro, in ovo, in vivo and ex vivo model systems. Ligand (HGF) binding leads to receptor dimerization and phosphorylation of tyrosine kinase domain of cMET. This activates the cMET signaling cascade. The representative downstream metastasis and angiogenesis-related proteins get upregulated and induce the metastasis and angiogenesis process. But after the QC treatment, cMET get dephosphorylated and inactivated. As a result, the downstream signaling proteins of cMET along with the other representative metastatic and angiogenic factors get downregulated. These lead to inhibition of cMET-mediated metastasis and angiogenesis. (Created with BioRender.com).

Inferring ligand-receptor cellular networks from bulk and spatial transcriptomic datasets with BulkSignalR

The study of cellular networks mediated by ligand-receptor interactions has attracted much attention recently owing to single-cell omics. However, rich collections of bulk data accompanied with clinical information exists and continue to be generated with no equivalent in single-cell so far. In parallel, spatial transcriptomic (ST) analyses represent a revolutionary tool in biology. A large number of ST projects rely on multicellular resolution, for instance the Visium™ platform, where several cells are analyzed at each location, thus producing localized bulk data. Here, we describe BulkSignalR, a R package to infer ligand-receptor networks from bulk data. BulkSignalR integrates ligand-receptor interactions with downstream pathways to estimate statistical significance. A range of visualization methods complement the statistics, including functions dedicated to spatial data. We demonstrate BulkSignalR relevance using different datasets, including new Visium liver metastasis ST data, with experimental validation of protein colocalization. A comparison with other ST packages shows the significantly higher quality of BulkSignalR inferences. BulkSignalR can be applied to any species thanks to its built-in generic ortholog mapping functionality.

Pharmacokinetic/Pharmacodynamic Analysis of Savolitinib plus Osimertinib in an EGFR Mutation-Positive, MET-Amplified Non-Small Cell Lung Cancer Model

Osimertinib is a third-generation, irreversible, oral EGFR tyrosine kinase inhibitor (TKI) recommended as first-line treatment for patients with locally advanced/metastatic EGFR mutation-positive (EGFRm) non-small cell lung cancer (NSCLC). However, MET amplification/overexpression is a common acquired osimertinib resistance mechanism. Savolitinib is an oral, potent, and highly selective MET-TKI; preliminary data suggest that combining osimertinib with savolitinib may overcome MET-driven resistance. A patient-derived xenograft (PDX) mouse model with EGFRm, MET-amplified NSCLC was tested with a fixed osimertinib dose [10 mg/kg for exposures equivalent to (≈)80 mg], combined with doses of savolitinib (0-15 mg/kg, ≈0-600 mg once daily), both with 1-aminobenzotriazole (to better match clinical half-life). After 20 days of oral dosing, samples were taken at various time points to follow the time course of drug exposure in addition to phosphorylated MET and EGFR (pMET and pEGFR) change. Population pharmacokinetics, savolitinib concentration versus percentage inhibition from baseline in pMET, and the relationship between pMET and tumor growth inhibition (TGI) were also modeled. As single agents, savolitinib (15 mg/kg) showed significant antitumor activity, reaching ∼84% TGI, and osimertinib (10 mg/kg) showed no significant antitumor activity (34% TGI, P > 0.05 vs. vehicle). Upon combination, at a fixed dose of osimertinib, significant savolitinib dose-related antitumor activity was shown, ranging from 81% TGI (0.3 mg/kg) to 84% tumor regression (15 mg/kg). Pharmacokinetic-pharmacodynamic modeling showed that the maximum inhibition of both pEGFR and pMET increased with increasing savolitinib doses. Savolitinib demonstrated exposure-related combination antitumor activity when combined with osimertinib in the EGFRm MET-amplified NSCLC PDX model.

Pharmacological impact of microRNAs in head and neck squamous cell carcinoma: Prevailing insights on molecular pathways, diagnosis, and nanomedicine treatment

Head and neck squamous cell carcinoma is a disease that most commonly produce tumours from the lining of the epithelial cells of the lips, larynx, nasopharynx, mouth, or oro-pharynx. It is one of the most deadly forms of cancer. About one to two percent of all neo-plasm-related deaths are attributed to head and neck squamous cell carcinoma, which is responsible for about six percent of all cancers. MicroRNAs play a critical role in cell proliferation, differentiation, tumorigenesis, stress response, triggering apoptosis, and other physiological process. MicroRNAs regulate gene expression and provide new diagnostic, prognostic, and therapeutic options for head and neck squamous cell carcinoma. In this work, the role of molecular signaling pathways related to head and neck squamous cell carcinoma is emphasized. We also provide an overview of MicroRNA downregulation and overexpression and its role as a diagnostic and prognostic marker in head and neck squamous cell carcinoma. In recent years, MicroRNA nano-based therapies for head and neck squamous cell carcinoma have been explored. In addition, nanotechnology-based alternatives have been discussed as a promising strategy in exploring therapeutic paradigms aimed at improving the efficacy of conventional cytotoxic chemotherapeutic agents against head and neck squamous cell carcinoma and attenuating their cytotoxicity. This article also provides information on ongoing and recently completed clinical trials for therapies based on nanotechnology.

Therapeutic targeting of anoikis resistance in cutaneous melanoma metastasis

The acquisition of resistance to anoikis, the cell death induced by loss of adhesion to the extracellular matrix, is an absolute requirement for the survival of disseminating and circulating tumour cells (CTCs), and for the seeding of metastatic lesions. In melanoma, a range of intracellular signalling cascades have been identified as potential drivers of anoikis resistance, however a full understanding of the process is yet to be attained. Mechanisms of anoikis resistance pose an attractive target for the therapeutic treatment of disseminating and circulating melanoma cells. This review explores the range of small molecule, peptide and antibody inhibitors targeting molecules involved in anoikis resistance in melanoma, and may be repurposed to prevent metastatic melanoma prior to its initiation, potentially improving the prognosis for patients.

Acquired resistance mechanisms to osimertinib: The constant battle

Lung cancer is the leading cause of cancer-related mortality worldwide. Detectable driver mutations have now changed the course of lung cancer treatment with the emergence of targeted therapy as a novel strategy that widely improved lung cancer prognosis, especially in metastatic patients. Osimertinib (AZD9291) is an irreversible third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) used to treat stage IV EGFR-mutated non-small-cell lung cancer. It was initially designed to target both EGFR-activating mutations and the EGFR T790M mutation as well, which is the most common resistance mechanism to first- and second-generation EGFR-TKIs. Following the FLAURA trial, osimertinib is now widely used in the first-line setting. However, resistance to osimertinib inevitably develops, with numerous mechanisms leading to its resistance, classified into two main categories: EGFR-dependent and EGFR-independent mechanisms. While EGFR-dependent mechanisms consist mainly of the C797S EGFR mutation, EGFR-independent mechanisms include bypass pathways, oncogenic fusions, and phenotypic transformation, among others. This review summarizes the molecular resistance mechanisms to osimertinib, with the aim of identifying novel therapeutic approaches to overcome osimertinib resistance and improve patient outcome.

Identification of Protein Biomarkers of the Dietary Approaches to Stop Hypertension Diet in Randomized Feeding Studies and Validation in an Observational Study

Background The Dietary Approaches to Stop Hypertension (DASH) diet is recommended for cardiovascular disease prevention. We aimed to identify protein biomarkers of the DASH diet using data from 2 randomized feeding studies and validate them in an observational study, the ARIC (Atherosclerosis Risk in Communities) study. Methods and Results Large-scale proteomic profiling was conducted in serum specimens (SomaLogic) collected at the end of 8-week and 4-week DASH diet interventions in multicenter, randomized controlled feeding studies of the DASH trial (N=215) and the DASH-Sodium trial (N=396), respectively. Multivariable linear regression models were used to compare the relative abundance of 7241 proteins between the DASH and control diet interventions. Estimates from the 2 trials were meta-analyzed using fixed-effects models. We validated significant proteins in the ARIC study (N=10 490) using the DASH diet score. At a false discovery rate <0.05, there were 71 proteins that were different between the DASH diet and control diet in the DASH and DASH-Sodium trials. Nineteen proteins were validated in the ARIC study. The 19 proteins collectively improved the prediction of the DASH diet intervention in the feeding studies (range of difference in C statistics, 0.267-0.313; P<0.001 for both tests) and the DASH diet score in the ARIC study (difference in C statistics, 0.017; P<0.001) beyond participant characteristics. Conclusions We identified 19 proteins robustly associated with the DASH diet in 3 studies, which may serve as biomarkers of the DASH diet. These results suggest potential pathways that are impacted by consumption of the DASH diet. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT03403166, NCT00000608.

A transcriptomics approach to expand therapeutic options and optimize clinical trials in oncology

Background

The current model of clinical drug development in oncology displays major limitations due to a high attrition rate in patient enrollment in early phase trials and a high failure rate of drugs in phase III studies.

Objective

Integrating transcriptomics for selection of patients has the potential to achieve enhanced speed and efficacy of precision oncology trials for any targeted therapies or immunotherapies.

Methods

Relative gene expression level in the metastasis and normal organ-matched tissues from the WINTHER database was used to estimate in silico the potential clinical benefit of specific treatments in a variety of metastatic solid tumors.

Results

As example, high mRNA expression in tumor tissue compared to analogous normal tissue of c-MET and its ligand HGF correlated in silico with shorter overall survival (OS; p < 0.0001) and may constitute an independent prognostic marker for outcome of patients with metastatic solid tumors, suggesting a strategy to identify patients most likely to benefit from MET-targeted treatments. The prognostic value of gene expression of several immune therapy targets (PD-L1, CTLA4, TIM3, TIGIT, LAG3, TLR4) was investigated in non-small-cell lung cancers and colorectal cancers (CRCs) and may be useful to optimize the development of their inhibitors, and opening new avenues such as use of anti-TLR4 in treatment of patients with metastatic CRC.

Conclusion

This in silico approach is expected to dramatically decrease the attrition of patient enrollment and to simultaneously increase the speed and detection of early signs of efficacy. The model may significantly contribute to lower toxicities. Altogether, our model aims to overcome the limits of current approaches.

Detection of MET gene somatic mutations in hepatocellular carcinoma of Egyptian patients using next-generation sequencing

INTRODUCTION

Hepatocellular carcinoma (HCC) is the sixth most common type of cancer worldwide and fourth in Egypt. Liquid biopsy is important to get cell-tumour DNA (ctDNA), for subsequent utilisation as a biomarker for cancer diagnosis, prognosis, and treatment. In clinical oncology, ctDNA analysis is utilised in cancer screening.

METHODS

The collected 48 blood samples from HCC patients were classified according to Barcelona Clinic Liver Cancer (BCLC) staging, in addition to Hepatitis C Virus (HCV) group and normal group. After the liquid biopsy, ctDNA and genomic DNA (gDNA) of the same individual were extracted. Next-generation sequencing (NGS) was conducted using a Hot spot panel, and data analysis via different cancer databases was performed.

RESULTS

There were no significant differences in the detected mutation frequency between groups. The frequency of mutations was higher in ctDNA than in the gDNA samples from the same patients. Hence, it can be concluded that these mutations are somatic mutations, rather than germline mutations.

CONCLUSION

Screening of the targeted genes such as c-MET for potential mutations is very important in the determination of the appropriate therapy. Therefore, it can be used as a biomarker in the prognosis of HCC. Such screenings are also of paramount importance in the development of personalised medicine.

Targeting MET and FGFR in Relapsed or Refractory Acute Myeloid Leukemia: Preclinical and Clinical Findings, and Signal Transduction Correlates

PURPOSE

Patients with relapsed/refractory (R/R) acute myeloid leukemia (AML) have poor outcomes and require new therapies. In AML, autocrine production of hepatocyte growth factor (HGF) drives MET signaling that promotes myeloblast growth and survival, making MET an attractive therapeutic target. MET inhibition exhibits activity in AML preclinical studies, but HGF upregulation by the FGFR pathway is a common mechanism of resistance.

PATIENTS AND METHODS

We performed preclinical studies followed by a Phase I trial to investigate the safety and biological activity of the MET inhibitor merestinib in combination with the FGFR inhibitor LY2874455 for patients with R/R AML. Study Cohort 1 underwent a safety lead-in to determine a tolerable dose of single-agent merestinib. In Cohort 2, dose-escalation of merestinib and LY2874455 was performed following a 3+3 design. Correlative studies were conducted.

RESULTS

The primary dose-limiting toxicity (DLT) observed for merestinib alone or with LY2874455 was reversible grade 3 transaminase elevation, occurring in 2 of 16 patients. Eight patients had stable disease and one achieved complete remission (CR) without measurable residual disease. Although the MTD of combination therapy could not be determined due to drug supply discontinuation, single-agent merestinib administered at 80 mg daily was safe and biologically active. Correlative studies showed therapeutic plasma levels of merestinib, on-target attenuation of MET signaling in leukemic blood, and increased HGF expression in bone marrow aspirate samples of refractory disease.

CONCLUSIONS

We provide prospective, preliminary evidence that MET and FGFR are biologically active and safely targetable pathways in AML.

Up-regulation of PUM1 by miR-218-5p promotes colorectal tumor-initiating cell properties and tumorigenesis by regulating the PI3K/AKT axis

Background

Colorectal cancer (CRC) is the third most common cancer and the fourth most common cause of cancer-related death worldwide. Advanced stage CRC, during the recent past, had a dismal prognosis and only a few available treatments. Pumilio homologous protein 1 (PUM1) is reportedly aberrant in human malignancies, including CRC. However, the role of PUM1 in the regulation of tumor-initiating cells (T-ICs) remains unknown.

Methods

The levels of messenger RNAs (mRNAs) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunoblot analyses. Statistical analyses were performed to determine the associations between the levels of PUM1 and tumor features and patient outcomes. Whether PUM1 is a downstream target of miR-218-5p was verified by bioinformatics target gene prediction and qRT-PCR.

Results

Herein, it was found that T-ICs, chemoresistance, and recurrent CRC samples all manifest increased PUM1 expression. Functional investigations have shown that PUM1 increased the self-renewal, tumorigenicity, malignant proliferation, and chemoresistance of colorectal cells. PUM1 activates the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway biochemically. Furthermore, it was discovered that miR-218-5p specifically targets T-ICs' PUM1 3'-untranslated region (3'-UTR). More importantly, the PUM1/PI3K/AKT axis regulates CRC cells' responses to treatment with cetuximab, and PUM1 overexpression increased cetuximab resistance. More evidence points to the possibility that low PUM1 may predict cetuximab benefits in CRC patients after analysis of the patient cohort, patient-derived tumor organoids, and patient-derived xenografts (PDXs).

Conclusions

Taken together, the result of this work points to the critical function of the miR-218-5p/PUM1/PI3K/AKT regulatory circuit in regulating T-ICs characteristics and thus suggests possible therapeutic targets for CRC.

Downstream Targets of VHL/HIF-α Signaling in Renal Clear Cell Carcinoma Progression: Mechanisms and Therapeutic Relevance

The clear cell variant of renal cell carcinoma (ccRCC) is the most common renal epithelial malignancy and responsible for most of the deaths from kidney cancer. Patients carrying inactivating mutations in the Von Hippel-Lindau (VHL) gene have an increased proclivity to develop several types of tumors including ccRCC. Normally, the Hypoxia Inducible Factor alpha (HIF-α) subunits of the HIF heterodimeric transcription factor complex are regulated by oxygen-dependent prolyl-hydroxylation, VHL-mediated ubiquitination and proteasomal degradation. Loss of pVHL function results in elevated levels of HIF-α due to increased stability, leading to RCC progression. While HIF-1α acts as a tumor suppressor, HIF-2α promotes oncogenic potential by driving tumor progression and metastasis through activation of hypoxia-sensitive signaling pathways and overexpression of HIF-2α target genes. One strategy to suppress ccRCC aggressiveness is directed at inhibition of HIF-2α and the associated molecular pathways leading to cell proliferation, angiogenesis, and metastasis. Indeed, clinical and pre-clinical data demonstrated the effectiveness of HIF-2α targeted therapy in attenuating ccRCC progression. This review focuses on the signaling pathways and the involved genes (cyclin D, c-Myc, VEGF-a, EGFR, TGF-α, GLUT-1) that confer oncogenic potential downstream of the VHL-HIF-2α signaling axis in ccRCC. Discussed as well are current treatment options (including receptor tyrosine kinase inhibitors such as sunitinib), the medical challenges (high prevalence of metastasis at the time of diagnosis, refractory nature of advanced disease to current treatment options), scientific challenges and future directions.

Ran GTPase and Its Importance in Cellular Signaling and Malignant Phenotype

Ran is a member of the Ras superfamily of proteins, which primarily regulates nucleocytoplasmic trafficking and mediates mitosis by regulating spindle formation and nuclear envelope (NE) reassembly. Therefore, Ran is an integral cell fate determinant. It has been demonstrated that aberrant Ran expression in cancer is a result of upstream dysregulation of the expression of various factors, such as osteopontin (OPN), and aberrant activation of various signaling pathways, including the extracellular-regulated kinase/mitogen-activated protein kinase (ERK/MEK) and phosphatidylinositol 3-kinase/Protein kinase B (PI3K/Akt) pathways. In vitro, Ran overexpression has severe effects on the cell phenotype, altering proliferation, adhesion, colony density, and invasion. Therefore, Ran overexpression has been identified in numerous types of cancer and has been shown to correlate with tumor grade and the degree of metastasis present in various cancers. The increased malignancy and invasiveness have been attributed to multiple mechanisms. Increased dependence on Ran for spindle formation and mitosis is a consequence of the upregulation of these pathways and the ensuing overexpression of Ran, which increases cellular dependence on Ran for survival. This increases the sensitivity of cells to changes in Ran concentration, with ablation being associated with aneuploidy, cell cycle arrest, and ultimately, cell death. It has also been demonstrated that Ran dysregulation influences nucleocytoplasmic transport, leading to transcription factor misallocation. Consequently, patients with tumors that overexpress Ran have been shown to have a higher malignancy rate and a shorter survival time compared to their counterparts.

Current therapeutic modalities and chemopreventive role of natural products in liver cancer: Progress and promise

Liver cancer is a severe concern for public health officials since the clinical cases are increasing each year, with an estimated 5-year survival rate of 30%–35% after diagnosis. Hepatocellular carcinoma (HCC) constitutes a significant subtype of liver cancer (approximate75%) and is considered primary liver cancer. Treatment for liver cancer mainly depends on the stage of its progression, where surgery including, hepatectomy and liver transplantation, and ablation and radiotherapy are the prime choice. For advanced liver cancer, various drugs and immunotherapy are used as first-line treatment, whereas second-line treatment includes chemotherapeutic drugs from natural and synthetic origins. Sorafenib and lenvatinib are first-line therapies, while regorafenib and ramucirumab are second-line therapy. Various metabolic and signaling pathways such as Notch, JAK/ STAT, Hippo, TGF-β, and Wnt have played a critical role during HCC progression. Dysbiosis has also been implicated in liver cancer. Drug-induced toxicity is a key obstacle in the treatment of liver cancer, necessitating the development of effective and safe medications, with natural compounds such as resveratrol, curcumin, diallyl sulfide, and others emerging as promising anticancer agents. This review highlights the current status of liver cancer research, signaling pathways, therapeutic targets, current treatment strategies and the chemopreventive role of various natural products in managing liver cancer.

Halorotetin A: A Novel Terpenoid Compound Isolated from Ascidian Halocynthia rotetzi Exhibits the Inhibition Activity on Tumor Cell Proliferation

Halocynthia roretzi, the edible ascidian, has been demonstrated to be an important source of bioactive natural metabolites. Here, we reported a novel terpenoid compound named Halorotetin A that was isolated from tunic ethanol extract of H. roretzi by silica gel column chromatography, preparative layer chromatography (PLC), and semipreparative-HPLC. 1H and 13C NMRs, 1H-1H COSY, HSQC, HMBC, NOESY, and HRESIMS profiles revealed that Halorotetin A was a novel terpenoid compound with antitumor potentials. We therefore treated the culture cells with Halorotetin A and found that it significantly inhibited the proliferation of a series of tumor cells by exerting cytotoxicity, especially for the liver carcinoma cell line (HepG-2 cells). Further studies revealed that Halorotetin A affected the expression of several genes associated with the development of hepatocellular carcinoma (HCC), including oncogenes (c-myc and c-met) and HCC suppressor genes (TP53 and KEAP1). In addition, we compared the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells. To our surprise, the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells were similar at the same concentration and Halorotetin A did not significantly reduce the viability of the normal cells. Thus, our study identified a novel compound that significantly inhibited the proliferation of tumor cells, which provided the basis for the discovery of leading compounds for antitumor drugs.

A New Model of Esophageal Cancers by Using a Detergent-Free Decellularized Matrix in a Perfusion Bioreactor

The lack of physiologically relevant human esophageal cancer models has as a result that many esophageal cancer studies are encountering major bottleneck challenges in achieving breakthrough progress. To address the issue, here we engineered a 3D esophageal tumor tissue model using a biomimetic decellularized esophageal matrix in a customized bioreactor. To obtain a biomimetic esophageal matrix, we developed a detergent-free, rapid decellularization method to decellularize porcine esophagus. We characterized the decellularized esophageal matrix (DEM) and utilized the DEM for the growth of esophageal cancer cell KYSE30 in well plates and the bioreactor. We then analyzed the expression of cancer-related markers of KYSE30 cells and compared them with formalin-fixed, paraffin-embedded (FFPE) esophageal squamous cell carcinoma (ESCC) tissue biospecimens. Our results show that the detergent-free decellularization method preserved the esophageal matrix components and effectively removed cell nucleus. KYSE30 cancer cells proliferated well on and inside the DEM. KYSE30 cells cultured on the DEM in the dynamic bioreactor show different cancer marker expressions than those in the static well plate, and also share some similarities to the FFPE-ESCC biospecimens. These findings built a foundation with potential for further study of esophageal cancer behavior in a biomimetic microenvironment using this new esophageal cancer model.

Molecular pathways, resistance mechanisms and targeted interventions in non-small-cell lung cancer

Lung cancer is the leading cause of cancer-related mortality worldwide. The discovery of tyrosine kinase inhibitors effectively targeting EGFR mutations in lung cancer patients in 2004 represented the beginning of the precision medicine era for this refractory disease. This great progress benefits from the identification of driver gene mutations, and after that, conventional and new technologies such as NGS further illustrated part of the complex molecular pathways of NSCLC. More targetable driver gene mutation identification in NSCLC patients greatly promoted the development of targeted therapy and provided great help for patient outcomes including significantly improved survival time and quality of life. Herein, we review the literature and ongoing clinical trials of NSCLC targeted therapy to address the molecular pathways and targeted intervention progress in NSCLC. In addition, the mutations in EGFR gene, ALK rearrangements, and KRAS mutations in the main sections, and the less common molecular alterations in MET, HER2, BRAF, ROS1, RET, and NTRK are discussed. The main resistance mechanisms of each targeted oncogene are highlighted to demonstrate the current dilemma of targeted therapy in NSCLC. Moreover, we discuss potential therapies to overcome the challenges of drug resistance. In this review, we manage to display the current landscape of targetable therapeutic patterns in NSCLC in this era of precision medicine.

Non-small cell lung cancer with MET exon 14 skip mutation: case report

Background

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, making up 80-85% of all lung malignancies. It can be further subdivided into different types. The three main subtypes are adenocarcinoma, squamous cell carcinoma, and large cell carcinoma. Traditionally, NSCLCs have been treated with a combination of chemotherapy, surgery, and/or radiation therapy. However, with the advent of genotype subtype analysis and targeted therapy it has become possible to have individualized treatment options for patients with NSCLC.

Case Description

We present a case report of a 68-year-old female with NSCLC. Patient initially only received radiation therapy due to her not being a surgical candidate. While initial treatment was responsive, later imaging showed metastasis of disease. Subsequent genotype analysis of the patient's tumor indicated a MET exon 14 skipping mutation which qualified her for treatment with Capmatinib (Tabrecta).

Conclusions

Patients on Capmatinib have minimal side effects and better efficacy than traditional chemotherapy. Patients with MET exon 14 skipping mutations should be considered for Capmatinib therapy.

Blockade of c-Met-Mediated Signaling Pathways by E7050 Suppresses Growth and Promotes Apoptosis in Multidrug-Resistant Human Uterine Sarcoma Cells

E7050 is a potent inhibitor of c-Met receptor tyrosine kinase and has potential for cancer therapy. However, the underlying molecular mechanism involved in the anti-cancer property of E7050 has not been fully elucidated. The main objective of this study was to investigate the anti-tumor activity of E7050 in multidrug-resistant human uterine sarcoma MES-SA/Dx5 cells in vitro and in vivo, and to define its mechanisms. Our results revealed that E7050 reduced cell viability of MES-SA/Dx5 cells, which was associated with the induction of apoptosis and S phase cell cycle arrest. Additionally, E7050 treatment significantly upregulated the expression of Bax, cleaved PARP, cleaved caspase-3, p21, p53 and cyclin D1, while it downregulated the expression of survivin and cyclin A. On the other hand, the mechanistic study demonstrated that E7050 inhibited the phosphorylation of c-Met, Src, Akt and p38 in HGF-stimulated MES-SA/Dx5 cells. Further in vivo experiments showed that treatment of athymic nude mice carrying MES-SA/Dx5 xenograft tumors with E7050 remarkably suppressed tumor growth. E7050 treatment also decreased the expression of Ki-67 and p-Met, and increased the expression of cleaved caspase-3 in MES-SA/Dx5 tumor sections. Therefore, E7050 is a promising drug that can be developed for the treatment of multidrug-resistant uterine sarcoma.

Lipocalin 2 Reduces MET Levels by Inhibiting MEK/ERK Signaling to Inhibit Nasopharyngeal Carcinoma Cell Migration

Nasopharyngeal carcinoma (NPC) is the most common cancer that occurs in the nasopharynx, and it is difficult to detect early. The main cause of death of NPC patients is cancer metastasis. Lipocalin 2 (LCN2) has been shown to be involved in a variety of carcinogenesis processes. Here, we aimed to study the role of LCN2 in NPC cells and determine its underlying mechanism. We found that LCN2 was expressed differently in NPC cell lines, namely HONE-1, NPC-39, and NPC-BM. The down-regulation of LCN2 levels by siRNA targeting LCN2 (siLCN2) increased cell migration and invasion in HONE-1 cells, while the up-regulation of LCN2 levels by transfection with the LCN2 expression plasmid decreased cell migration and invasion in NPC-BM cells. Furthermore, LCN2 levels negatively regulated the phosphorylation of MEK/ERK pathways. The treatment of the specific MEK/ERK inhibitor, U0126, reduced cell migration in HONE-1 cells, whereas the treatment of tBHQ, an ERK activator, enhanced cell migration in NPC-BM cells. Based on the bioinformatics data, there was a moderately negative correlation between LCN2 and MET in metastatic NPC tissues (r = -0.5946, p = 0.0022). Indeed, the manipulation of LCN2 levels negatively regulated MET levels in these NPC cells. The treatment of U0126 reduced siLCN2-increased MET levels, while the treatment of tBHQ enhanced LCN2-enhanced MET levels. Interestingly, the down-regulation of MET levels by siMET further decreased siLCN2-enhanced MET levels and cell migration. Therefore, LCN2 inhibits NPC cell migration by reducing MET levels through MEK/ERK signaling.

Study of the anticancer effect of new quinazolinone hydrazine derivatives as receptor tyrosine kinase inhibitors

The advent of novel receptor tyrosine kinase inhibitors has provided an important therapeutic tool for cancer patients. In this study, a series of quinazolinone hydrazide triazole derivatives were designed and synthesized as novel MET (c-MET) receptor tyrosine kinase inhibitors. The antiproliferative effect of the synthesized compounds was examined against EBC-1, A549, HT-29 and U-87MG cells by MTT assay. MET kinase inhibitory effect was tested by a Homogenous Time Resolved Fluorescence (HTRF) assay. The antiproliferative effect of compounds in a three-dimensional spheroid culture was studied by acid phosphatase (APH) assay, while apoptosis induction was examined by Hoechst 33258 staining. We found that compound CM9 bearing p-bromo benzyl pendant inhibited MET kinase activity at the concentrations of 10-50 μM (% Inhibition = 37.1-66.3%). Compound CM9 showed antiproliferative effect against cancer cells, in particular lung cancer cells with MET amplification (EBC-1) with an IC50 value of 8.6 μM. Moreover, this derivative inhibited cell growth in spheroid cultures in a dose-dependent manner and induced apoptosis in cancer cells. Assessment of inhibitory effect of CM9 against a panel of 18 different protein kinases demonstrated that this compound also inhibits ALK, AXL, FGFR1, FLT1 (VEGFR1) and FLT4 (VEGFR3) more than 50% at 25 μM. Finally, molecular docking and dynamics simulation corroborated the experimental findings and showed critical structural features for the interactions between CM9 and target kinases. The findings of this study present quinazolinone hydrazide triazole derivatives as kinase inhibitors with considerable anticancer effects.

Preclinical characterization and phase I clinical trial of CT053PTSA targets MET, AXL, and VEGFR2 in patients with advanced solid tumors

BACKGROUND

CT053PTSA is a novel tyrosine kinase inhibitor that targets MET, AXL, VEGFR2, FLT3 and MERTK. Here, we present preclinical data about CT053PTSA, and we conducted the first-in-human (FIH) study to evaluate the use of CT053PTSA in adult patients with pretreated advanced solid tumors.

METHODS

The selectivity and antitumor activity of CT053PTSA were assessed in cell lines in vitro through kinase and cellular screening panels and in cell line-derived tumor xenograft (CDX) and patient-derived xenograft (PDX) models in vivo. The FIH, phase I, single-center, single-arm, dose escalation (3 + 3 design) study was conducted, patients received at least one dose of CT053PTSA (15 mg QD, 30 mg QD, 60 mg QD, 100 mg QD, and 150 mg QD). The primary objectives were to assess safety and tolerability, to determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), and the recommended dose of CT053PTSA for further study. Secondary objectives included pharmacokinetics, antitumor activity.

RESULTS

CT053 (free-base form of CT053PTSA) inhibited MET, AXL, VEGFR2, FLT3 and MERTK phosphorylation and suppressed tumor cell angiogenesis by blocking VEGF and HGF, respectively, in vitro. Moreover, cell lines with high MET expression exhibited strong sensitivity to CT053, and CT053 blocked the MET and AXL signaling pathways. In an in vivo study, CT053 significantly inhibited tumor growth in CDX and PDX models. Twenty eligible patients were enrolled in the FIH phase I trial. The most common treatment-related adverse events were transaminase elevation (65%), leukopenia (45%) and neutropenia (35%). DLTs occurred in 3 patients, 1/6 in the 100 mg group and 2/4 in the 150 mg group, so the MTD was set to 100 mg. CT053PTSA was rapidly absorbed after the oral administration of a single dose, and the Cmax and AUC increased proportionally as the dose increased. A total of 17 patients in this trial underwent tumor imaging evaluation, and 29.4% had stable disease.

CONCLUSIONS

CT053PTSA has potent antitumor and antiangiogenic activity in preclinical models. In this FIH phase I trial, CT053PTSA was well tolerated and had a satisfactory safety profile. Further trials evaluating the clinical activity of CT053PTSA are ongoing.

MiR-23b-3p suppresses epithelial-mesenchymal transition, migration, and invasion of hepatocellular carcinoma cells by targeting c-MET

Background

Aberrant expression of c-MET is known to be associated with tumor recurrence and metastasis by promoting cell proliferation, epithelial-mesenchymal transition (EMT), and migration in hepatocellular carcinoma (HCC). Recently, miR-23b-3p has been identified as a tumor suppressor, but detailed role of miR-23b-3p in HCC is still unclear. Our study aimed to investigate how miR-23b-3p is associated with the malignant potential of HCC cells.

Methods

HCC tissues and their adjacent non-tumor tissues were acquired from 30 patients with HCC. Expression of EMT- or stemness-related genes were examined in the two HCC cell lines. Migration of HCC cells was analyzed using transwell and wound healing assays.

Results

c-MET was overexpressed in HCC tissues compared to the adjacent non-tumor tissues. c-MET knockdown inhibited EMT and reduced migration and invasion of HCC cells. Furthermore, c-MET was a target of miR-23b-3p, and miR-23b-3p expression was decreased in HCC tissues compared to non-tumor tissues. Treatment of miR-23b-3p inhibitor in HCC cells promoted EMT, cell migration, and invasion. In contrast, miR-23b-3p overexpression suppressed EMT, cell migration, and invasion, concomitantly reducing c-MET expression. Transfection of miR-23b-3p inhibitor with concomitant c-MET knockdown mitigated the effects of miR-23b-3p inhibitor on EMT in HCC cells. In addition, transforming growth factor beta1 (TGF-β1) stimulation after miR-23b-3p overexpression induced neither the mesenchymal phenotype nor migratory property of HCC cells.

Conclusion

In this study, we confirmed that miR-23b-3p downregulation significantly increased EMT, migration, and invasion of HCC cells. In addition, c-MET was confirmed to be a target of miR-23b-3p in HCC cells and regulated the functional effects of miR-23b-3p. These results suggest that miR-23b-3p can be used as a prognostic biomarker and candidate target for HCC treatment.

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c-MET is a target of miR-23b-3p and overexpressed in HCC tissues.

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MiR-23b-3p expression was decreased in HCC tissues compared to non-tumor tissues.

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Inhibition of miR-23b-3p induced migration and invasion via EMT in HCC cells.

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MiR-23b-3p/c-MET axis may serve as a therapeutic target for HCC.

Procaine Abrogates the Epithelial-Mesenchymal Transition Process through Modulating c-Met Phosphorylation in Hepatocellular Carcinoma

Simple Summary

Epithelial-mesenchymal transition (EMT) is a vital process that leads to the dissemination of tumor cells to distant organs and promotes cancer progression. Aberrant activation of c-Met has been positively correlated with tumor metastasis in hepatocellular carcinoma (HCC). In this report, we have demonstrated the suppressive effect of procaine on the EMT process through the blockade of the c-Met signaling pathway. Procaine downregulated mesenchymal markers and upregulated epithelial markers. Functionally, procaine abrogated cellular migration and invasion. Moreover, procaine suppressed c-Met and its downstream signaling events in HCC models. We report that procaine can function as a novel inhibitor of the EMT process and c-Met-dependent signaling cascades. These results support the consideration of procaine being tested as a potential anti-metastatic agent.

Abstract

EMT is a critical cellular phenomenon that promotes tumor invasion and metastasis. Procaine is a local anesthetic agent used in oral surgeries and as an inhibitor of DNA methylation in some types of cancers. In this study, we have investigated whether procaine can inhibit the EMT process in HCC cells and the preclinical model. Procaine suppressed the expression of diverse mesenchymal markers but induced the levels of epithelial markers such as E-cadherin and occludin in HGF-stimulated cells. Procaine also significantly reduced the invasion and migration of HCC cells. Moreover, procaine inhibited HGF-induced c-Met and its downstream oncogenic pathways, such as PI3K/Akt/mTOR and MEK/ERK. Additionally, procaine decreased the tumor burden in the HCC mouse model and abrogated lung metastasis. Overall, our study suggests that procaine may inhibit the EMT process through the modulation of a c-Met signaling pathway.