Critical update and emerging trends in epidermal growth factor receptor targeting in cancer

A Label-Free Approach for Cell-Level Drug Dosage Response Tests With an Optimized Flow Cytometry Device

Cancer is among the most significant health threats to humanity. As a critical front-line treatment in the early stages of the disease, chemotherapy drugs provide positive effects on more than one disease. Traditional analytical methods for screening these drugs are often marred by the need for intricate sample preparation and reliance on costly equipment or reagents. In this study, we profiled the biophysical properties of cancer cells (MCF-7) as they traversed a detection region using a high-throughput seven-electrode double-differential biochip. To ensure precise and reliable cell status assessment, we optimized both the electrode dimensions within the assay system and the buffer's conductivities. Our findings indicated that an electrode configuration of E:F:G = 2:5:1 (E, F, and G stand for exciting/floating/gap, respectively), coupled with a conductivity setting of 1.6 S/m, was optimal for probing the electrical properties of breast cancer cells (MCF-7). Utilizing this refined system, we achieved a live-dead cell differentiation accuracy of approximately 94.25%. Moreover, MCF-7 cells displayed distinct impedance signatures in response to varying drug concentrations. Changes in impedance signal characteristics, such as opacity and phase, stand for the physiological shifts within the cells under drug exposure. This research is of considerable importance, offering a novel and efficient methodology for drug dosage response testing. It paves the way for more precise and personalized cancer treatment strategies, potentially enhancing patient outcomes and quality of life.

Design, synthesis, and molecular dynamics-driven evaluation of quinoline-sulfonamide derivatives as potent and selective EGFR inhibitors with promising anti-cancer efficacy and safety profiles

The creation of new molecules that target EGFR is essential for the progression of cancer treatment. This study synthesized and evaluated 16 quinoline-sulfonamide derivatives for their potential as anti-cancer agents. Compound 8c, which contains a methoxy group on the benzenesulfonamide tail, exhibited notable EGFR inhibitory activity (IC50 = 0.161 µM), similar to that of Erlotinib (IC50 = 0.142 µM). Compound 8c demonstrated enhanced in-vitro cytotoxicity against HCT-116, MCF-7, HeLa, and HepG2 cancer cell lines. Studies on the cell cycle and apoptosis demonstrated that compound 8c caused G1/S arrest and markedly enhanced apoptosis in HepG2 cells. In-vivo, compound 8c demonstrated comparable and/or superior efficacy compared to doxorubicin in decreasing tumor volume, weight, TNF-alpha, and COX-2 levels in the SEC model, alongside improved histopathological and immunohistochemical results. Molecular docking and dynamic simulations confirmed its stable binding to EGFR, exhibiting superior stability metrics in comparison to Erlotinib. Pharmacokinetic and toxicity evaluations indicated that compound 8c exhibits favorable drug-like properties and a safer toxicity profile. These findings identify compound 8c as a potential candidate for the development of safe and effective anti-cancer therapies, necessitating additional preclinical investigations.

An Overview of Cellular and Molecular Determinants Regulating Chemoresistance in Pleural Mesothelioma

Malignant pleural mesothelioma (PM) is a highly aggressive disease of the lung pleura associated with poor prognosis. Despite advances in improving the clinical management of this malignancy, there is no effective chemotherapy for refractory or relapsing PM. The acquisition of resistance to standard and targeted therapy in this disease is a foremost concern; therefore, a deeper understanding of the complex factors surrounding the emergence of drug resistance is deemed necessary. In this review, we will present broad insights into various cellular and molecular concepts, accounting for the recalcitrance of PM to chemotherapy, including signaling networks regulating drug tolerance, drug resistance-associated proteins, genes, and miRNAs, as well as the critical role of cancer stem cells. Identification of the biological determinants and their associated mechanisms may provide a framework for the development of appropriate treatment.

Magnetic lipid-poly(lactic-co-glycolic acid) nanoparticles conjugated with epidermal growth factor receptor antibody for dual-targeted delivery of CPT-11

To entrap sparingly water-soluble drugs like CPT-11 (irinotecan), the poly(lactic-co-glycolic acid) (PLGA) nanoparticle (NP) is highly favored due to its low cytotoxicity and approval for clinical use. On the other hand, entrapping hydrophobic oleic acid-coated iron oxide magnetic nanoparticles (OMNP) in PLGA NP can provide a nanovehicle for magnetically targeted drug delivery. Our goal in this study is to develop a new dual-targeted magnetic lipid-polymer NP for the delivery of CPT-11. We first co-entrap OMNP and CPT-11 in self-assembled lipid-PLGA NP to prepare OLNP@CPT-11. The OLNP@CPT-11 surface was modified with an epidermal growth factor receptor (EGFR) antibody Cetuximab (CET), which can actively target the overexpressed EGFR on the U87 glioblastoma cell surface. The OLNP-CET@CPT-11 enables dual targeting through both external magnetic guidance and CET-mediated active targeting. The NP was characterized for physicochemical properties using various analytical techniques. In vitro study confirms ligand-receptor interaction results in enhanced endocytosis of OLNP-CET@CPT-11 by U87 cells, which offers increased cytotoxicity and elevated cell apoptosis rates. Furthermore, magnetic guidance of OLNP-CET@CPT-11 to U87 cells can induce cell death exclusively in the magnetically targeted zone. The dual-targeted strategy also provides the best therapeutic efficacy against subcutaneously implanted U87 tumors in nude mice with intravenously delivered OLNP-CET@CPT-11.

Novel EGFR inhibitors against resistant L858R/T790M/C797S mutant for intervention of non-small cell lung cancer

To overcome C797S mutation, the latest and most common resistance mechanism in the clinical treatment of third-generation EGFR inhibitor, a novel series of substituted 6-(2-aminopyrimidine)-indole derivatives were designed and synthesized. Through the structure-activity relationship (SAR) study, compound 11eg was identified as a novel and potent EGFR L858R/T790M/C797S inhibitor (IC50 = 0.053 μM) but had a weak effect on EGFRWT (IC50 = 1.05 μM). 11eg significantly inhibited the proliferation of the non-small cell lung cancer (NSCLC) cells harboring EGFRL858R/T790M/C797S with an IC50 of 0.052 μM. 11eg also showed potent inhibitory activity against other NSCLC cell lines harboring main EGFR mutants. Furthermore, 11eg exhibited much superior activity in arresting cell cycle and inducing apoptosis of NSCLC cells with mutant EGFRC797S. It blocked cellular EGFR signaling. Importantly, 11eg markedly suppressed the tumor growth in in vivo xenograft mouse model with good safety. Additionally, 11eg displayed good microsomal stability. These results demonstrated the potential of 11eg with novel scaffold as a promising lead compound targeting EGFRC797S to guide in-depth structural optimization.

From Bench to Bedside: A Team's Approach to Multidisciplinary Strategies to Combat Therapeutic Resistance in Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is diagnosed in more than 71,000 patients each year in the United States, with nearly 16,000 associated deaths. One significant hurdle in the treatment of HNSCC is acquired and intrinsic resistance to existing therapeutic agents. Over the past several decades, the University of Wisconsin has formed a multidisciplinary team to move basic scientific discovery along the translational spectrum to impact the lives of HNSCC patients. In this review, we outline key discoveries made throughout the years at the University of Wisconsin to deepen our understanding of therapeutic resistance in HNSCC and how a strong, interdisciplinary team can make significant advances toward improving the lives of these patients by combatting resistance to established therapeutic modalities. We are profoundly grateful to the many scientific teams worldwide whose groundbreaking discoveries, alongside evolving clinical paradigms in head and neck oncology, have been instrumental in making our work possible.

Discovery of new cyclopropane sulfonamide derivatives as EGFR inhibitors to overcome C797S-mediated resistance and EGFR double mutation

The C797S mutation of EGFR leads to Osimertinib resistance by blocking the covalent binding of Cys797. To develop new agents that can overcome EGFR mutation resistance, thirty seven new cyclopropane sulfonamide derivatives were synthesized and evaluated as EGFRL858R/T790M/C797S or EGFRDel19/T790M/C797S inhibitors by structure-based screening. Most of the synthesized compounds exhibit good to excellent anti proliferation activity against to BaF3-EGFR L858R/T790M/C797S and BaF3-C797S/Del19/T790M cancer cell lines. Representative compounds 8l showed inhibitory activity against the two cancer cell lines with the IC50 values of 0.0012 and 0.0013 μM, respectively. Another compound 8h, exhibited slightly lower activity (0.0042 and 0.0034 μM of the IC50 values) to both of the two tri-mutation cell lines, but excellent activities against H1975 and PC9 cells with IC50 values of 13 and 19 nM, respectively. Considering the acquired drug resistance of tumors is a gradual process, we chose 8h for further in vivo and mechanism study. 8h was demonstrated significantly inhibited tumor growth with 72.1 % of the TGI in the BaF3/EGFR-TM xenograft tumor model and 83.5 % in the H1975-DM xenograft tumor model. Compound 8h was confirmed to be safe with no significant side effects as showed by the results of in vitro assay of human normal cells and the sections of animals major organs. Mechanism studies showed that in addition to inhibiting EGFR mutations, 8h can also target the tumor microenvironment and induce tumor cell apoptosis. All these results indicate that 8h deserves further investigation as an EGFR inhibitor to overcome C797S-mediated resistance.

Single cell lineage tracing reveals clonal dynamics of anti-EGFR therapy resistance in triple negative breast cancer

BACKGROUND

Most primary Triple Negative Breast Cancers (TNBCs) show amplification of the Epidermal Growth Factor Receptor (EGFR) gene, leading to increased protein expression. However, unlike other EGFR-driven cancers, targeting this receptor in TNBC yields inconsistent therapeutic responses.

METHODS

To elucidate the underlying mechanisms of this variability, we employ cellular barcoding and single-cell transcriptomics to reconstruct the subclonal dynamics of EGFR-amplified TNBC cells in response to afatinib, a tyrosine kinase inhibitor (TKI) that irreversibly inhibits EGFR.

RESULTS

Integrated lineage tracing analysis revealed a rare pre-existing subpopulation of cells with distinct biological signature, including elevated expression levels of Insulin-Like Growth Factor Binding Protein 2 (IGFBP2). We show that IGFBP2 overexpression is sufficient to render TNBC cells tolerant to afatinib treatment by activating the compensatory insulin-like growth factor I receptor (IGF1-R) signalling pathway. Finally, based on reconstructed mechanisms of resistance, we employ deep learning techniques to predict the afatinib sensitivity of TNBC cells.

CONCLUSIONS

Our strategy proved effective in reconstructing the complex signalling network driving EGFR-targeted therapy resistance, offering new insights for the development of individualized treatment strategies in TNBC.

A bioorthogonal cell sorting strategy for isolation of desired cell phenotypes

Here we describe a cost-effective and simplified cell sorting method using tetrazine bioorthogonal chemistry. We successfully isolated SKOV3 cells from complex mixtures, demonstrating efficacy in separating mouse lymphocytes expressing interferon and HeLa cells expressing virally transduced green fluorescent protein post-infection.

Design, synthesis and biological evaluation of potent epidermal growth factor receptor tyrosine kinase (EGFR-TK) inhibitors against resistance mutation for lung cancer treatment

In this study, we identified a newly synthesized compound 7o with potent inhibition on EGFR primary mutants (L858R, Del19) and drug-resistant mutant T790M with nanomolar IC50 values. 7o showed strong antiproliferative effects against EGFR mutant-driven non-small cell lung cancer (NSCLC) cells such as H1975, PC-9 and HCC827, over cells expressing EGFRWT. Molecular docking was performed to investigate the possible binding modes of 7o inside the binding site of EGFRL858R/T790M and EGFRWT. Analysis of cell cycle evidenced that 7o induced cell cycle arrest in G1 phases in the EGFR mutant cells, H1975 and PC-9, which resulted in decreased S-phase populations. Moreover, compound 7o induced cancer cell apoptosis in in vitro assays. In addition, 7o inhibited cellular phosphorylation of EGFR. In vivo, oral administration of 7o caused rapid tumor regression in H1975 xenograft model. Therefore, 7o might deserve further optimization as cancer treatment agent for EGFR mutant-driven NSCLC.

Molecular Docking, Pharmacokinetic and Molecular Simulation Analysis of Novel Mono-Carbonyl Curcumin Analogs as L858R/T790M/C797S Mutant EGFR Inhibitors

INTRODUCTION

Curcumin, an anticancer natural compound with multiple pharmacological activities, has a weak pharmacokinetic and instability due to diketone moiety. Curcumin's stability challenges can be overcome by removing the diketone moiety and shortening the 7-carbon chain, resulting in mono-carbonyl analogs. Cancer proliferation is caused by the activation of Epidermal Growth Factor (EGFR) pathways. Current available EGFR inhibitors have an issue of resistance.

AIM

Thus, we aimed to design new mono-carbonyl curcumin derivatives and analyse their drug likeness properties. Further, to investigate them on three distinct crystal structures, namely two wild-type and L858R/T790M/C797S mutant generations for EGFR inhibitory activity.

METHOD

Ten New Molecular Entities (NME's) were designed using literature survey. These molecules were subjected to comparative molecular docking, on the EGFR crystal structures viz. wild-type (PDB: 1M17 and 4I23) and L858R/T790M/C797S mutant (PDB: 6LUD) using Schrodinger software. The molecules were also tested for Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties. The docked complex of the hit molecule was studied for molecular simulation.

RESULT AND DISCUSSION

In molecular docking studies, NMEs 1, 2, and 3 were found to have good binding affinity with 1st , 2nd , and 3rd generation EGFR crystal structures and a greater dock score than standard curcumin. All molecules have shown a good ADMET profile. Since L858R/T790M/C797S is currently being explored more, we decided to take the best molecule, NME 3, for molecular dynamics with 6LUD, and the results were compared with those of the co-crystallized ligand S4 (Osimertinib). It was found that the Relative mean square standard deviation (RMSD) (1.8 Å), Relative mean standard Fluctuation (RMSF) (1.45 Å) and radius of gyration (4.87 Å) values of NME 3 were much lower than those of reference S4. All these confirm that our designed NME 3 is more stable than reference S4.

CONCLUSION

NME 1 and NME 2 have shown better binding against wild type of EGFR. NME 3 have shown comparable binding and more stability as compared to Osimertinib against L858R/T790M/C797S mutated protein structure. The hit compound can be further explored for its Molecular mechanics with generalised Born and surface area solvation (MM-GBSA) and discrete Fourier transform (DFT) studies to find out the energy and atomic level study. In the future, this molecule could be taken for wet lab studies and can be tested for mutated EGFR inhibitory activity.

RUNX3 regulates the susceptibility against EGFR-targeted non-small cell lung cancer therapy using 47Sc-conjugated cetuximab

BACKGROUND

Radioimmunotherapy with cetuximab and conjugates with various radioisotopes is a feasible treatment option for different tumor models. Scandium-47 (⁴⁷Sc), one of several β^--particle-emitting radioisotopes, displays favorable physical and chemical properties for conjugation to monoclonal antibodies. However, the therapeutic efficacy of ⁴⁷Sc in preclinical and clinical studies is largely unknown. Given that intrinsic alterations in tumors greatly contribute to resistance to anti-epidermal growth factor receptor (EGFR)-targeted therapy, research on overcoming resistance to radioimmunotherapy using cetuximab is required.

METHODS

⁴⁷Sc was produced by irradiation of a CaCO₃ target at the HANARO research reactor in KAERI (Korea Atomic Energy Research Institute) and prepared by chromatographic separation of the irradiated target. Cetuximab was conjugated with ⁴⁷Sc using the bifunctional chelating agent DTPA. Radiochemical purity was determined using instant thin-layer chromatography. The immunoreactivity of ⁴⁷Sc-DTPA-cetuximab was evaluated using the Lindmo method and an in vitro cell-binding assay. The inhibitory effects of cetuximab and ⁴⁷Sc-DTPA-cetuximab were confirmed using cell growth inhibition and BrdU cell proliferation assays. Differences in protein expression levels between cetuximab- and ⁴⁷Sc-DTPA-cetuximab-treated cells were confirmed using western blotting. Complex formation between RUNX3 and DNA repair components was confirmed using immunoprecipitation and western blotting.

RESULTS

Cetuximab induces cell cycle arrest and cell death in EGFR-overexpressing NSCLC cells. Radiolabeling of cetuximab with ⁴⁷Sc led to increased therapeutic efficacy relative to cetuximab alone. Application of ⁴⁷Sc-DTPA-cetuximab induced DNA damage responses, and activation of RUNX3 significantly enhanced the therapeutic efficacy of ⁴⁷Sc-DTPA-cetuximab. RUNX3 mediated susceptibility to EGFR-targeted NSCLC therapy using ⁴⁷Sc-DTPA-cetuximab via interaction with components of the DNA damage and repair machinery.

CONCLUSIONS

⁴⁷Sc-DTPA-cetuximab promoted cell death in EGFR-overexpressing NSCLC cells by targeting EGFR and inducing DNA damage as a result of β irradiation emitted from the conjugated ⁴⁷Sc. Activation of RUNX3 played a key role in DNA damage and repair processes in response to the ionizing radiation and inhibited cell growth, thus leading to more effective tumor suppression. RUNX3 can potentially moderate susceptibility to ⁴⁷Sc-conjugated cetuximab by modulating DNA damage and repair process mechanisms.

Efficacy and safety of adjuvant EGFR TKI alone and in combination with chemotherapy for resected EGFR mutation-positive non-small cell lung cancer: A Bayesian network meta-analysis

Adjuvant therapy with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), alone or with chemotherapy, is used for early-stage non-small cell lung cancer (NSCLC) with EGFR mutations. A Bayesian meta-analysis was conducted to compare the efficacy and safety of adjuvant EGFR-TKI and adjuvant chemotherapy plus EGFR-TKI to determine whether additional adjuvant chemotherapy is beneficial. Randomised controlled trials and retrospective comparative studies examining the efficacy of adjuvant EGFR-TKI were searched from inception to July 2022. Ten studies (1344 patients) were analysed. Disease-free survival (DFS), overall survival (OS), and adverse events (AEs) were the endpoints. Our network meta-analysis demonstrated that EGFR-TKI monotherapy is noninferior to chemotherapy plus EGFR-TKI for DFS and OS in the adjuvant setting. However, combination treatment was associated with a higher AE incidence and severity. Adjuvant EGFR-TKI monotherapy seems a viable alternative to chemotherapy plus EGFR-TKI in patients with resected EGFR mutation-positive NSCLC.

Antitumor effects of erlotinib in combination with berberine in A431 cells

BACKGROUND

First-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as erlotinib, have been shown to target tumors with L858R (exon 21) and exon 19 deletions, resulting in significant clinical benefits. However, acquired resistance often occurs due to EGFR mutations. Therefore, novel therapeutic strategies for treatment of patients with EGFR-positive tumors are needed. Berberine (BBR) is an active alkaloid extracted from pharmaceutical plants such as Coptis chinensis. Berberine has been shown to significantly inhibit EGFR activity and mediate anticancer effects in multiple preclinical studies. We investigated whether combining BBR with erlotinib could augment erlotinib-induced cell growth inhibition of EGFR-positive cells in a mouse xenograft model.

METHODS

We examined the antitumor activities and potential mechanisms of erlotinib in combination with berberine in vitro and in vivo using the MTT assay, immunoblotting, flow cytometry, and tumor xenograft models.

RESULTS

In vitro studies with A431 cells showed that synergistic cell growth inhibition by the combination of BBR and erlotinib was associated with significantly greater inhibition of pEGFR and pAKT, and inhibition of cyclin D and Bcl-2 expression compared to that observed in response to BBR or erlotinib alone. The efficacy of the combination treatment was also investigated in nude mice. Consistent with the in vitro results, BBR plus erlotinib significantly reduced tumor growth.

CONCLUSION

Our data supported use of BBR in combination with erlotinib as a novel strategy for treatment of patients with EGFR positive tumors.

An ultra-performance LC-MS/MS method for determination of JRF103 in human plasma: application in first-in-patient study

Background: JRF103, a novel pan-HER inhibitor, has shown potent activity against HER1, HER2, HER4 and EGFR in vitro. To support its first-in-patient trial, a sensitive and rapid method was developed and validated using ultra-performance LC-MS/MS. Materials & methods: JRF103 was extracted from plasma using protein precipitation. Extracts were subjected to ultra-performance LC-MS/MS with electrospray ionization. Results: Separation of analyte was achieved using a 1.7-μm C₁₈ column (2.1 × 50-mm internal diameter) with a gradient elution. The developed method was fully validated following the international guides. Conclusion: The developed method was sensitive, specific and suitable for measuring JRF103 concentration in patients with advanced solid tumors in the first-in-patient study of JRF103.

Effects of Para-Toluenesulfonamide on Canine Melanoma Xenotransplants in a BALB/c Nude Mouse Model

The pharmacological pathway of para-toluenesulfonamide (PTS) restricts the kinase activity of the mammalian target of rapamycin, potentially leading to reductions in cell division, cell growth, cell proliferation, and inflammation. These pathways have a critical effect on tumorigenesis. We aimed to examine the antitumor effect of PTS or PTS combined with cisplatin on canine melanoma implanted in BALB/c nude mice by estimating tumor growth, apoptosis expression, inflammation, and metastasis. The mice were randomly divided into four groups: control, cisplatin, PTS, and PTS combined with cisplatin. Mice treated with PTS or PTS combined with cisplatin had retarded tumor growth and increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase phosphorylation, decreased inflammatory cytokine levels, reduced inflammation-related factors, enhanced anti-inflammation-related factors, and inhibition of metastasis-related factors. Mice treated with PTS combined with cisplatin exhibited significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with those treated with cisplatin or PTS alone. PTS or PTS combined with cisplatin could retard canine melanoma growth and inhibit tumorigenesis. PTS and cisplatin were found to have an obvious synergistic tumor-inhibiting effect on canine melanoma. PTS alone and PTS combined with cisplatin may be antitumor agents for canine melanoma treatment.

Near-Infrared-Emissive AIE Bioconjugates: Recent Advances and Perspectives

Near-infrared (NIR) fluorescence materials have exhibited formidable power in the field of biomedicine, benefiting from their merits of low autofluorescence background, reduced photon scattering, and deeper penetration depth. Fluorophores possessing planar conformation may confront the shortcomings of aggregation-caused quenching effects at the aggregate level. Fortunately, the concept of aggregation-induced emission (AIE) thoroughly reverses this dilemma. AIE bioconjugates referring to the combination of luminogens showing an AIE nature with biomolecules possessing specific functionalities are generated via the covalent conjugation between AIEgens and functional biological species, covering carbohydrates, peptides, proteins, DNA, and so on. This perfect integration breeds unique superiorities containing high brightness, good water solubility, versatile functionalities, and prominent biosafety. In this review, we summarize the recent progresses of NIR-emissive AIE bioconjugates focusing on their design principles and biomedical applications. Furthermore, a brief prospect of the challenges and opportunities of AIE bioconjugates for a wide range of biomedical applications is presented.

Receptor, Signal, Nucleus, Action: Signals That Pass through Akt on the Road to Head and Neck Cancer Cell Migration

This review aims to provide evidence for the role of the tumour microenvironment in cancer progression, including invasion and metastasis. The tumour microenvironment is complex and consists of tumour cells and stromal-derived cells, in addition to a modified extracellular matrix. The cellular components synthesise growth factors such as EGF, TGFα and β, VEGF, and NGF, which have been shown to initiate paracrine signalling in head and neck cancer cells by binding to cell surface receptors. One example is the phosphorylation, and hence activation, of the signalling protein Akt, which can ultimately induce oral cancer cell migration in vitro. Blocking of Akt activation by an inhibitor, MK2206, leads to a significant decrease, in vitro, of cancer-derived cell migration, visualised in both wound healing and scatter assays. Signalling pathways have therefore been popular targets for the design of chemotherapeutic agents, but drug resistance has been observed and is related to direct tumour-tumour cell communication, the tumour-extracellular matrix interface, and tumour-stromal cell interactions. Translation of this knowledge to patient care is reliant upon a comprehensive understanding of the complex relationships present in the tumour microenvironment and could ultimately lead to the design of efficacious treatment regimens such as targeted therapy or novel therapeutic combinations.

Molecular dynamic simulations based discovery and development of thiazolidin-4-one derivatives as EGFR inhibitors targeting resistance in non-small cell lung cancer (NSCLC)

Targeting kinases with oncogenic driver mutations in malignancies with allosteric kinase inhibitors is a promising new treatment technique. EGFR inhibitors targeting the L858R/T790M/C797S mutation bearing thiazolidine-4-one scaffold were discovered, optimized, synthesized, and biologically evaluated. According to in silico and in vitro studies, compounds 6a and 6b resulted to be highly potent with IC₅₀ values of 120 nM and 134 nM and good selectivity. Compound 6a displayed significant antioxidant activity, with a DPPH radical scavenging value of 92.15%. The potency of compounds was also compared with ADMET and molecular dynamics simulations study. A comparative simulation of model protein and protein-ligand complex in presence and absence of compound 6a has been carried out. Communicated by Ramaswamy H. Sarma.

FTO mediated ERBB2 demethylation promotes tumor progression in esophageal squamous cell carcinoma cells

N⁶-methyladenosine (m⁶A) is the most prevalent and internal modification that occurs in the messenger RNAs of eukaryotes. However, knowledge of the impact of these modifications on gene expression regulation remains limited. By using the in vitro MeRIP-seq and RNA-seq assays, we discovered that the mRNA demethylase FTO was significantly up-regulated in esophageal squamous cell carcinoma (ESCC) tissues and cells. Knockdown of FTO drastically suppressed the proliferation, migration, and invasion of ESCC cells. Furthermore, by using transcriptome-wide m⁶A-seq and RNA-seq assays, we identified ERBB2 is the target of FTO, which acts in concert in ESCC tumorigenesis and metastasis. Moreover, loss and gain functional studies suggested that the m⁶A reader YTHDF1 stabilizes ERBB2 mRNA via decoding the m⁶A modification. All these results uncovered a new signaling cascade, including FTO, YTHDF1, and ERBB2, which finely regulates the ESCC progression.

Comparative genomic analysis of esophageal squamous cell carcinoma and adenocarcinoma: New opportunities towards molecularly targeted therapy

Esophageal cancer is one of the most lethal cancers worldwide because of its rapid progression and poor prognosis. Esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) are two major subtypes of esophageal cancer. ESCC predominantly affects African and Asian populations, which is closely related to chronic smoking and alcohol consumption. EAC typically arises in Barrett's esophagus with a predilection for Western countries. While surgical operation and chemoradiotherapy have been applied to combat this deadly cancer, molecularly targeted therapy is still at the early stages. With the development of large-scale next-generation sequencing, various genomic alterations in ESCC and EAC have been revealed and their potential roles in the initiation and progression of esophageal cancer have been studied. Potential therapeutic targets have been identified and novel approaches have been developed to combat esophageal cancer. In this review, we comprehensively analyze the genomic alterations in EAC and ESCC and summarize the potential role of the genetic alterations in the development of esophageal cancer. Progresses in the therapeutics based on the different tissue types and molecular signatures have also been reviewed and discussed.

Small Molecule Compounds of Natural Origin Target Cellular Receptors to Inhibit Cancer Development and Progression

Receptors are macromolecules that transmit information regulating cell proliferation, differentiation, migration and apoptosis, play key roles in oncogenic processes and correlate with the prognoses of cancer patients. Thus, targeting receptors to constrain cancer development and progression has gained widespread interest. Small molecule compounds of natural origin have been widely used as drugs or adjuvant chemotherapeutic agents in cancer therapies due to their activities of selectively killing cancer cells, alleviating drug resistance and mitigating side effects. Meanwhile, many natural compounds, including those targeting receptors, are still under laboratory investigation for their anti-cancer activities and mechanisms. In this review, we classify the receptors by their structures and functions, illustrate the natural compounds targeting these receptors and discuss the mechanisms of their anti-cancer activities. We aim to provide primary knowledge of mechanistic regulation and clinical applications of cancer therapies through targeting deregulated receptors.

Quinoline–hydrazone hybrids as dual mutant EGFR inhibitors with promising metallic nanoparticle loading: rationalized design, synthesis, biological investigation and computational studies

A novel quinoline–hydrazone hybrid induced apoptosis in MCF-7 cells through dual mutant EGFR inhibition with promising metallic nanoparticle loading.

Enhancement of NK Cell Antitumor Effector Functions Using a Bispecific Single Domain Antibody Targeting CD16 and the Epidermal Growth Factor Receptor

Simple Summary

Strategies to enhance the preferential accumulation and activation of Natural Killer (NK) cells in the tumor microenvironment can be expected to increase the efficacy of NK cell-based cancer immunotherapy. In this study, we report that a bispecific single domain antibody (VHH) that targets CD16 (FcRγIII) on NK cells and the epidermal growth factor receptor (EGFR) on tumor cells can be used to target and enhance cytolysis of cancer cells. The bispecific VHH enhanced NK cell activation and cytotoxicity in an EGFR- and CD16-dependent and KRAS-independent manner. Moreover, the bispecific VHH induced stronger activity of cancer patient-derived NK cells and resulted in tumor control in a co-culture of metastatic colorectal cancer cells and either autologous peripheral blood mononuclear cells or allogeneic CD16⁺ NK cells. We believe that this novel approach could represent a valid therapeutic strategy either alone or in combination with other NK cell-based therapies.

Abstract

The ability to kill tumor cells while maintaining an acceptable safety profile makes Natural Killer (NK) cells promising assets for cancer therapy. Strategies to enhance the preferential accumulation and activation of NK cells in the tumor microenvironment can be expected to increase the efficacy of NK cell-based therapies. In this study, we show binding of a novel bispecific single domain antibody (VHH) to both CD16 (FcRγIII) on NK cells and the epidermal growth factor receptor (EGFR) on tumor cells of epithelial origin. The bispecific VHH triggered CD16- and EGFR-dependent activation of NK cells and subsequent lysis of tumor cells, regardless of the KRAS mutational status of the tumor. Enhancement of NK cell activation by the bispecific VHH was also observed when NK cells of colorectal cancer (CRC) patients were co-cultured with EGFR expressing tumor cells. Finally, higher levels of cytotoxicity were found against patient-derived metastatic CRC cells in the presence of the bispecific VHH and autologous peripheral blood mononuclear cells or allogeneic CD16 expressing NK cells. The anticancer activity of CD16-EGFR bispecific VHHs reported here merits further exploration to assess its potential therapeutic activity either alone or in combination with adoptive NK cell-based therapeutic approaches.

Distinguishing features of a novel humanized anti-EGFR monoclonal antibody based on cetuximab with superior antitumor efficacy

BACKGROUND

Cetuximab, the first approved EGFR targeting therapeutic antibody, is currently used to treat colorectal cancer and head and neck cancer. While effective, cetuximab is associated with a higher rate of skin rash, infusion reactions, and gastrointestinal toxicity, which was suggested to be linked to the presence of heterogeneous glycan contents on the Fab of the SP2/0-produced cetuximab.

OBJECTIVE AND METHODS

To improve efficacy and minimize toxicity of EGFR inhibition treatment, we re-engineered cetuximab by humanizing its Fab regions and minimizing its glycan contents to generate HLX07.

RESULTS

HLX07 binds to EGFR with similar affinity as cetuximab and shows better bioactivity compared to cetuximab in vitro. In vivo studies demonstrated that HLX07 significantly inhibited the growth of A431, FaDu, NCI-H292, and WiDr tumor cells and synergized them with chemotherapeutics and immune simulator agents such as anti-PD-1. In cynomolgus monkeys, 13-week repeat-dose GLP toxicokinetic studies showed minimal-to-mild toxicities in the dose range of up to 60 mg/kg/wk. In the preliminary phase 1 dose-escalation study, HLX07 had showed lower incidence of skin rashes with grade >2 severities.

CONCLUSION

HLX07 is currently under phase 1/2 clinical development. We believe HLX07 would potentially be an alternative for patients who have been suffering from cetuximab-mediated toxicity.

Prognostic Impact of Membranous/Nuclear Epidermal Growth Factor Receptor Localization in Clear Cell Renal Cell Carcinoma

EGFR is overexpressed in the majority of clear cell renal cell carcinomas (CCRCCs). Although EGFR deregulation was found to be of great significance in CCRCC biology, the EGFR overexpression is not associated with EGFR-targeted therapy responsiveness. Moreover, the prognostic role of EGFR expression remains controversial. In the present study, we evaluated the role played by EGFR overexpression in CCRCC and its prognostic significance associated with different immunohistochemical localization patterns. In our study, the Total Score (TS) related to membranous-cytoplasmic EGFR expression showed a significant correlation with grade, pathologic stage (pT), and Stage, Size, Grade, and Necrosis (SSIGN) score, and a negative correlation with nuclear EGFR expression. No significant correlations were shown between nuclear EGFR and clinic-pathological features. Additionally, a correlation between SGLT1 expression levels and pT was described. Multivariate analysis identifies pT and SSIGN score as independent prognostic factors for CCRCC. A significantly increased survival rate was found in the case of positive expression of nuclear EGFR and SGLT1. Based on our findings, SGLT1 and nuclear EGFR overexpression defines a subgroup of CCRCC patients with good prognosis. Membranous-cytoplasmic EGFR expression was shown to be a poor prognostic factor and could define a CCRCC subgroup with poor prognosis that should be responsive to anti-EGFR therapies.

Anti-Cancer Effects of Zotarolimus Combined with 5-Fluorouracil Treatment in HCT-116 Colorectal Cancer-Bearing BALB/c Nude Mice

Zotarolimus is a semi-synthetic derivative of rapamycin and an inhibitor of mammalian target of rapamycin (mTOR) signaling. Currently, zotarolimus is used to prolong the survival time of organ grafts, but it is also a novel immunosuppressive agent with potent anti-proliferative activity. Here, we examine the anti-tumor effect of zotarolimus, alone and in combination with 5-fluorouracil, on HCT-116 colorectal adenocarcinoma cells implanted in BALB/c nude mice. Compared with the control mice, mice treated with zotarolimus or zotarolimus combined with 5-FU showed retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; reduced inflammation-related factors such as IL-1β, TNF-α, and cyclooxygenase-2 (COX-2) protein; and inhibited metastasis-related factors such as CD44, epidermal growth factor receptor (EGFR), transforming growth factor β (TGF-β), and vascular endothelial growth factor (VEGF). Notably, mice treated with a combination of zotarolimus and 5-FU showed significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with mice treated with 5-FU or zotarolimus alone, indicating a strong synergistic effect. This in vivo study confirms that zotarolimus or zotarolimus combined with 5-FU can be used to retard colorectal adenocarcinoma growth and inhibit tumorigenesis. Our results suggest that zotarolimus may increase the chemo-sensitization of tumor cells. Therefore, zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents in the treatment of human colon adenocarcinoma. Future research on zotarolimus may lead to the development of new therapeutic strategies.

Free energy perturbation guided Synthesis with Biological Evaluation of Substituted Quinoline derivatives as small molecule L858R/T790M/C797S mutant EGFR inhibitors targeting resistance in Non-Small Cell Lung Cancer (NSCLC)

Two different schemes of novel substituted quinoline derivatives were designed and synthesized via simple reaction steps and conditions. A comparative molecular docking study was carried out on two different types of EGFR enzymes which include wild-type (PDB: 4I23) and T790M mutated (PDB: 2JIV) respectively. Compounds were also validated upon T790M/C797S mutated (PDB ID: 5D41) EGFR enzyme at the allosteric binding site. Free energy perturbations were carried out to determine the absolute binding free energy of a protein-ligand complex in the form of ΔG_binding, which in turn provided 4ab and 5ad as the most potential contenders through the structural enhancement in the determined initial scaffolds. Anticancer activity of the synthesized derivatives was examined against HCC827, H1975 (L858R/T790M), A549, and HT-29 cell lines by standard MTT assay. Compound 4ad (6-chloro-2-(isoindolin-2-yl)-4-methylquinoline) has shown excellent inhibitory activities against mutant EGFR kinase with IC₅₀ value 0.91 µM. The potency of compounds 4ab, 4ad and 5adwas compared throughan insilicoADMET study.

Progress of molecular targeted therapy for head and neck cancer in clinical aspects

Since the body's head and neck area affects many functions such as breathing, swallowing, and speaking, systemic treatments to head and neck cancer patients are important not only for survival but also for preserving functions and quality of life. With the progress that has been made in molecular targeted therapy, anti-EGFR antibody (cetuximab) and immune checkpoint inhibitors (nivolumab, pembrolizumab) have provided survival benefits to head and neck cancer patients and are approved for clinical practice. Clinical trials incorporating these new drugs for patients with locally advanced head/neck cancers are underway. However, the existing clinical evidence regarding molecular targeted drugs for head and neck cancers is based mostly on clinical trials allocated to squamous cell carcinoma patients. New targeted therapies for non-squamous cell carcinoma patients were recently reported, e.g., tyrosine kinase inhibitors for the treatment of thyroid cancers and HER2-targeted therapy for salivary gland cancers. With the goal of improving local control, molecular targeted treatment strategies as salvage local therapy are being investigated, including boron neutron capture therapy (BNCT) and near-infrared photoimmunotherapy (NIR-PIT). Herein the history and landscape of molecular targeted therapy for head and neck cancers are summarized and reviewed.

Quantification of HER family dimers by proximity ligation assay and its clinical evaluation in non-small cell lung cancer patients treated with osimertinib

OBJECTIVES

The epidermal growth factor receptor (EGFR, also known as Her1) is a member of the human epidermal growth factor receptor (HER) family of proteins and a target of tyrosine kinase inhibitors (TKIs) in the treatment of non-small cell lung cancer (NSCLC) positive for activating mutations ofEGFR. Signal transduction by HER family proteins is dependent on their homo- or heterodimerization, but little is known of the relation between the relative proportions of such dimers of Her1 and sensitivity to EGFR-TKIs. We here investigated the feasibility of assessing this relation with the in situ proximity ligation assay (PLA) technique, which is able to detect the interaction of two proteins of interest when they are in close proximity.

MATERIALS AND METHODS

In situ PLA was applied to detect Her1 homodimers and Her1 heterodimers in NSCLC cell lines and tissue specimens positive for EGFR activating mutations.

RESULTS

In situ PLA allowed visualization and quantitative assessment of Her1 homodimers as well as of Her1 heterodimers with Her2, Her3, or Her4 not only in NSCLC cell lines but also in NSCLC tissue specimens obtained from various anatomic sites and by different collection methods. Treatment of NSCLC cell lines with EGFR-TKIs resulted in a decrease in the number of Her1 dimers, with the effect on homodimers being greater than that on heterodimers. A high ratio of Her1 heterodimers to homodimers was associated with poor progression-free survival in NSCLC patients treated with osimertinib.

CONCLUSION

In situ PLA allows the detection of HER family dimers in NSCLC tissue, and quantitative assessment of Her1 homo- and heterodimers may prove informative for prediction of the response of NSCLC patients to EGFR-TKI treatment.

Combined Treatment with JFKD and Gefitinib Overcomes Drug Resistance in Non-Small Cell Lung Cancer

BACKGROUND

Gefitinib is an important drug used to treat Non-Small Cell Lung Cancer (NSCLC) with EGFR activating mutations, but drug resistance restricts its clinical application. In this present study, combined Jin Fu Kang Decoction (JFKD) and gefitinib showed specific cytotoxicity to gefitinib-resistant cancer cells (PC-9/gef).

OBJECTIVE

This study aimed to decipher the molecular mechanism of the JFKD on drug resistance when used together with Gefitinib and to find the contributing bio-active substance(s) in JFKD based on the putative mechanism.

METHODS

To investigate the combined effect of gefitinib and JFKD, in vitro experiments were conducted on the established gefitinib-resistant PC-9 subclone, while in vivo experiments were conducted on the BALB/c nude mice with PC-9/gef xenografts. Western blot was used to evaluate the protein expression, and Ultra-Performance Liquid Chromatography (UPLC) coupled with quadrupole time-offlight Mass Spectrometry (MS) was used to detect the bio-active compounds of JFKD.

RESULTS

The expression of the PTEN-relevant protein p-EGFR, p-Akt in vitro was inhibited more when combined JKFD and gefitinib were used, whereas the activities of PDCD4 and PTEN were increased; remarkably, in vivo experiments showed enhanced tumor growth inhibition when treated with this combination. Due to this combination, the effect on the gefitinib-resistant cell line, one of the JFKD-induced anti-cancer mechanisms, was found. To link the putative mechanism and the anticancer compounds in JFKD, 14 saponins and flavonoids were detected.

CONCLUSION

The results suggested that a promising TCM-participated therapy can be established by the putative mechanism of the combined treatment in resistant NSCLC and screening the contributing bio-active substance(s) in JFKD is meaningful on new TCM formula discovery.

Role of EGFR and HER-2/NEU Expression in Gall Bladder Carcinoma (GBC)

Background  Gall bladder carcinoma (GBC) is the most common malignancy of the biliary tract. Being known for its geographical and racial variations, and compared with the global statistics, its incidence is higher in the Indian subcontinent, mainly in the northern and eastern regions, accounting for 80 to 95% of cases. Aims and Objectives  This study was conducted to evaluate the clinic-pathological spectrum and expression of EGFR and HER-2/NEU in GBCs and to understand their relation to prognosis, paving the way for targeted therapies for better treatment outcomes and patient survival. Materials and Methods  This is a prospective study performed in a tertiary care hospital in 30 resected specimens of GBC cases recorded in our Department of Pathology from November 2017 to November 2019. Clinical history including the radiological reports and demographic parameters were included in the study pro forma. Immunohistochemical (IHC) staining for EGFR and HER-2/NEU was performed on all the selected cases. Clinicopathologic parameters like age, sex, histologic type, perineural, and lymphovascular invasion were compared and correlated with EGFR and HER-2/NEU status. Results  Expression of EGFR was found in 93.33% of cases, which showed a highly significant correlation with histological tumor type ( p = 0.000). HER-2/NEU expression was found in 56.66% of cases, which also showed a significant correlation with histological tumour type ( p = 0.021). We found most of the cases with strong EGFR immunoreactivity (3+) were poorly differentiated tumors and most of the cases showing weak immunoreactivity for EGFR (1+) were well-differentiated. Conversely, in case of HER-2/NEU immunoreactivity, strong staining (3+) was seen in well-differentiated tumors and weak staining (1+) in poorly differentiated tumors. A significant correlation was also found between EGFR and HER-2/NEU expression ( p = 0.000) and between cholelithiasis and EGFR expression ( p = 0 .033). Conclusion  EGFR is expressed in most cases of GBC. Its expression is more in poorly differentiated carcinomas as compared to the well-differentiated carcinomas, whereas HER-2/NEU expression is more in well-differentiated carcinomas. Therefore, they may serve as independent prognostic factors and also as targets for molecular therapy in GBCs.

Clinicopathological profile and its association with peritoneal disease among gastric cancer patients

BACKGROUND

There are no clinicopathological criteria or test to predict peritoneal metastasis either in primary or recurrent gastric cancer. The early prediction will help in altering or adding other adjuvant potential therapy modalities like HIPEC and maintenance chemotherapy.

METHODS

Paraffin based blocks of 110 gastric tumor specimens were subjected to IHC staining to assess VEGF, Her 2 neu, E cadherin, bcl 2 and p 53 expression and its association with peritoneal disease evaluated.

RESULTS

Her 2 neu uptake was present in 17.3%, bcl-2 expression in 19.1%, P53 expression in 40.9%, VEGF in 41.8% and E cadherin expression in 49.1% patients. On univariate analysis, a younger age(p = .029), female sex(p = .026), positive VEGF expression (p = .001) and p53 expression(p = .015) were significantly associated with peritoneal disease. A binomial logistic regression was performed to ascertain the effects of independent variables evaluated on univariate analysis. Of the 10 predictors variables, only three were statistically significant: tumor type, P53, and VEGF. Positive VEGF expression had 48.7, E cadherin 2.6 and Her2neu 1.5 times higher odds of exhibiting peritoneal disease.

CONCLUSION

A younger age, female sex, distal 2/3rd, diffuse variant, VEGF staining in >10% cells and decrease p53 expression were associated with peritoneal disease.

The Anti-Cancer Effects of a Zotarolimus and 5-Fluorouracil Combination Treatment on A549 Cell-Derived Tumors in BALB/c Nude Mice

Zotarolimus is a semi-synthetic derivative of rapamycin and a novel immunosuppressive agent used to prevent graft rejection. The pharmacological pathway of zotarolimus restricts the kinase activity of the mammalian target of rapamycin (mTOR), which potentially leads to reductions in cell division, cell growth, cell proliferation, and inflammation. These pathways have a critical influence on tumorigenesis. This study aims to examine the anti-tumor effect of zotarolimus or zotarolimus combined with 5-fluorouracil (5-FU) on A549 human lung adenocarcinoma cell line implanted in BALB/c nude mice by estimating tumor growth, apoptosis expression, inflammation, and metastasis. We established A549 xenografts in nude mice, following which we randomly divided the mice into four groups: control, 5-FU (100 mg/kg/week), zotarolimus (2 mg/kg/day), and zotarolimus combined with 5-FU. Compared the results with those for control mice, we found that mice treated with zotarolimus or zotarolimus combined with 5-FU retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; decreased inflammation cytokines levels (e.g., IL-1β, TNF-α, and IL-6); reduced inflammation-related factors such as cyclooxygenase-2 (COX-2) protein and nuclear factor-κB (NF-κB) mRNA; enhanced anti-inflammation-related factors including IL-10 and inhibitor of NF-κB kinase α (IκBα) mRNA; and inhibited metastasis-related factors such as transforming growth factor β (TGF-β), CD44, epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF). Notably, mice treated with zotarolimus combined with 5-FU had significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with the groups of mice treated with 5-FU or zotarolimus alone. The in vivo study confirmed that zotarolimus or zotarolimus combined with 5-FU could retard lung adenocarcinoma growth and inhibit tumorigenesis. Zotarolimus and 5-FU were found to have an obvious synergistic tumor-inhibiting effect on lung adenocarcinoma. Therefore, both zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents for treatment of human lung adenocarcinoma.

1,3,4-Oxadiazole Containing Compounds As Therapeutic Targets For Cancer Therapy

BACKGROUND

Cancer is the first or second leading cause of premature death in 134 of 183 countries in the world. 1,3,4-Oxadiazoles are five memebered heterocyclic rings containing two nitrogen (two atoms) and oxygen (one atom). They show better thermal stability, metabolic stability, aqueous solubility and lower lipophilicity than the other isomeric oxadiazoles. They are important class of heterocycles present in many drug structures like Raltegravir, Furamizole Tidazosin, Nesapidil, Setileuton (MK-0633) and Zibotentan. Presence of this nucleus in the therapeutics has made them an indispensable anchor for drug design and development. Several 1,3,4-oxadiazoles are prepared and reported as anticancer agents by numerous scientists worldwide.

OBJECTIVES

The present review discusses the anticancer potentials together with the molecular targets of 1,3,4-oxadiazoles reported since 2010. The structure activity relationship (SAR) and molecular docking simulation on different targets have also been discussed herein. Some of the important cancer targets have also been explored.

METHODS

The most potent 1,3,4-oxadiazoles reported in literature was highlighted in the manuscript. The anticancer activity was reported in terms of growth percent (GP), percent growth inhibition (%GI), GI50, IC50, and LC50 and TGI.

RESULTS

1,3,4-Oxadiazoles are an important heterocyclic scaffolds with broad spectrum biological activities. They may be either mono substituted or disubstituted and act as an indispensable anchor for drug design and discovery due to their thermal stability together with low lipophilicity. They exhibited anticancer potentials and showed the inhibitions of various cancer targets.

CONCLUSION

The discussion outlined herein will proved to be a helpful and vital tool for medicinal chemists investigating and working with 1,3,4-oxadiazoles and anticancer research programs.

The human VRK1 chromatin kinase in cancer biology

VRK1 is a nuclear Ser-Thr chromatin kinase that does not mutate in cancer, and is overexpressed in many types of tumors and associated with a poor prognosis. Chromatin VRK1 phosphorylates several transcription factors, including p53, histones and proteins implicated in DNA damage response pathways. In the context of cell proliferation, VRK1 regulates entry in cell cycle, chromatin condensation in G2/M, Golgi fragmentation, Cajal body dynamics and nuclear envelope assembly in mitosis. This kinase also controls the initial chromatin relaxation associated with histone acetylation, and the non-homologous-end joining (NHEJ) DNA repair pathway, which involves sequential steps such as γH2AX, NBS1 and 53BP1 foci formation, all phosphorylated by VRK1, in response to ionizing radiation or chemotherapy. In addition, VRK1 can be an alternative target for therapies based on synthetic lethality strategies. Therefore, VRK1 roles on proliferation have a pro-tumorigenic effect. Functions regulating chromatin stability and DNA damage responses have a protective anti-tumor role in normal cells, but in tumor cells can also facilitate resistance to genotoxic treatments.

Review on Epidermal Growth Factor Receptor (EGFR) Structure, Signaling Pathways, Interactions, and Recent Updates of EGFR Inhibitors

The epidermal growth factor receptor (EGFR) belongs to the ERBB family of tyrosine kinase receptors. EGFR signaling cascade is a key regulator in cell proliferation, differentiation, division, survival, and cancer development. In this review, the EGFR structure and its mutations, signaling pathway, ligand binding and EGFR dimerization, EGF/EGFR interaction, and the progress in the development of EGFR inhibitors have been explored.

Computational and Synthetic approach with Biological Evaluation of Substituted Quinoline derivatives as small molecule L858R/T790M/C797S triple mutant EGFR inhibitors targeting resistance in Non-Small Cell Lung Cancer (NSCLC)

New substituted quinoline derivatives were designed and synthesized via a five-step modified Suzuki coupling reaction. A comparative molecular docking study was carried out on two different types of EGFR enzymes which include wild-type (PDB: 4I23) and T790M mutated (PDB: 2JIV) respectively. Compounds were also validated upon T790M/C797S mutated (PDB ID: 5D41) EGFR enzyme at the allosteric binding site. All docking studies confirmed high potency and flexibility towards wild type as well as a mutated enzyme. Anticancer activity of the synthesized derivatives was examined against HCC827, H1975 (L858R/T790M/C797S and L858R/T790M), A549, and HT-29 cell lines by standard MTT assay. Most of the quinoline derivatives revealed a significant cytotoxic effect. The IC50 values of 4-(4-methylquinolin-2-yl)phenyl 4-(chloromethyl)benzoate (5j) were found to be 0.0042 µM, 0.02 µM, 1.91 µM, 3.82 µM and 3.67 µM while IC50 values of osimertinib were 0.0040 µM, 0.02 µM, ND, 0.99 µM and 1.22 µM, respectively. Compound 5j has shownexcellent inhibitory activities against EGFR kinases triple mutant with IC 50 value 1.91 µM. It was observed that, compared to H1975, A549 and A431 cell lines, synthesized compounds significantly inhibited proliferation of the HCC827 cell line. These data suggested that synthesized compounds showed promising selective anticancer activity against tumor cells harboring EGFR Del E746-A750. The potency of compound 5j was compared through molecular dynamic simulations andan insilicoADMET study. QSAR models were generated and the best model was correctly compared with respect to predicted and observed activity of compounds. The built model will assist to design, refine and construct novel substituted quinoline derivatives as potent EGFR inhibitors in near future.

Protein kinases as targets for developing anticancer agents from marine organisms

Protein kinases play a fundamental role in the intracellular transduction because of their ability to phosphorylate plethora of proteins. Over the past three decades, numerous protein kinase inhibitors have been identified and are being used clinically successfully. The biodiversity of marine organisms provides a rich source for the discovery and development of novel anticancer agents in the treatment of human malignancies and a lot of bioactive ingredients from marine organisms display anticancer effects by affecting the protein kinases-mediated pathways. In the present mini-review, anticancer compounds from marine source were reviewed and discussed in context of their targeted pathways associated with protein kinases and the progress of these compounds as anticancer agents in recent five years were emphasized. The molecular entities and their modes of actions were presented. We focused on protein kinases-mediated signaling pathways including PI3K/Akt/mTOR, p38 MAPK, and EGFR. The marine compounds targeting special pathways of protein kinases were highlighted. We have also discussed the existing challenges and prospects related to design and development of novel protein kinase inhibitors from marine sources.

B-cell epitope peptide cancer vaccines: a new paradigm for combination immunotherapies with novel checkpoint peptide vaccine

In light of the numerous US FDA-approved humanized monoclonal antibodies (mAbs) for cancer immunotherapy, it is surprising that the advancement of B-cell epitope vaccines designed to elicit a natural humoral polyclonal antibody response has not gained traction in the immune-oncology landscape. Passive immunotherapy with humanized mAbs (Trastuzumab [Herceptin®]; Pertuzumab [Perjeta®]) has provided clinical benefit to breast cancer patients, albeit with significant shortcomings including toxicity problems and resistance, high costs, sophisticated therapeutic regimen and long half-life. The role of B-cell humoral immunity in cancer is under appreciated and underdeveloped. We have advanced the idea of active immunotherapy with chimeric B-cell epitope peptides incorporating a 'promiscuous' T-cell epitope that elicits a polyclonal antibody response, which provides safe, cost-effective therapeutic advantage over mAbs. We have created a portfolio of validated B-cell peptide epitopes against multiple receptor tyrosine kinases (HER-1, HER-3, IGF-1R and VEGF). We have successfully translated two HER-2 combination B-cell peptide vaccines in Phase I and II clinical trials. We have recently developed an effective novel PD-1 vaccine. In this article, I will review our approaches and strategies that focus on B-cell epitope cancer vaccines.

MiR-1299 Impedes the Progression of Non-Small-Cell Lung Cancer Through EGFR/PI3K/AKT Signaling Pathway

Background

Non-small-cell lung cancer (NSCLC) is one of the most malignant tumors. In which, numerous miRNAs had been reported to participate in the pathogenesis. However, the expression and function of miR-1299 in NSCLC are not clear.

Methods

To explore the roles of miR-1299 in NSCLC, we detected the levels of miR-1299 in clinical samples of NSCLC and investigated the role of miR-1299 in the regulation of the NSCLC cells proliferation, metastasis, and EMT. Luciferase reporter assay was employed to verify the target of miR-1299. Additionally, the proliferation, metastasis, and EMT of A549 and H1299 cells were analyzed after the overexpression and knockdown of miR-1299.

Results

We found that the miR-1299 expression negatively corresponded with the clinical stage and overall survival in NSCLC patients. Overexpression of miR-1299 inhibited the migration, invasion, and EMT of A549 and H1975 cells. Meanwhile, we proved that miR-1299 is the sponge of EGFR. Besides, our results suggested that miR-1299 inhibits the progression of NSCLC cells through the PI3K/Akt signal pathway.

Conclusion

We demonstrated that miR-1299 inhibits the progression of NSCLC through the EGFR/PI3K/Akt signal pathway. Therapeutic intervention targeting the miR-1299 may provide a potential strategy for the treatment of NSCLC.

LncZEB1-AS1 regulates hepatocellular carcinoma bone metastasis via regulation of the miR-302b-EGFR-PI3K-AKT axis

In patients with hepatocellular carcinoma (HCC), disease progression and associated bone metastasis (BM) can markedly reduce quality of life. While the long non-coding RNA (lncRNA) zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) has been shown to function as a key regulator of oncogenic processes in HCC and other tumor types, whether it plays a role in controlling HCC BM remains to be established. In the current study, we detected the significant upregulation of lncZEB1-AS1 in HCC tissues, and we found this expression to be associated with BM progression. When we knocked down this lncRNA in HCC cells, we found that this significantly reduced their migratory, invasive, and metastatic activity both in vitro and in vivo. At a mechanistic level, we found that lncZEB1-AS1 was able to target miR-302b and to thereby increase PI3K-AKT pathway activation and EGFR expression, resulting in the enhanced expression of downstream matrix metalloproteinase genes in HCC cells. In summary, our results provide novel evidence that lncZEB1-AS1 can promote HCC BM through a mechanism dependent upon the activation of PI3K-AKT signaling, thus highlighting a potentially novel therapeutic avenue for the treatment of such metastatic progression in HCC patients.

Role of hypoxia-related proteins in adenoid cystic carcinoma invasion

BACKGROUND

Among cancers affecting the oral cavity, adenoid cystic carcinoma (ACC) is a relatively common malignant neoplasm. It has high rates of metastasis and recurrence and is associated with significant morbidity. During the progression of ACC, the oxygen concentration is reduced in specific areas of the tumour microenvironment, leading to intratumoural hypoxia. The expression of NOTCH1, a disintegrin and metalloproteinase 12 (ADAM-12), hypoxia-inducible factor 1 alpha (HIF-1α), and heparin-binding epidermal growth factor (HB-EGF) under hypoxic conditions has been implicated in invadopodia formation, tumour invasiveness, and metastasis. The aim of this study was to analyse the expression of these proteins to elucidate the mechanisms underlying ACC invasiveness.

METHODS

Fifteen ACC samples and 10 normal-looking salivary gland (SG) samples were used to investigate the expression of these proteins by immunohistochemistry. Primary antibodies against NOTCH1, ADAM-12, HIF-1α, and HB-EGF were used.

RESULTS

The immunoexpression of all proteins was higher in ACC samples than in SG samples (p < 0.05).

CONCLUSIONS

There was increased expression of proteins associated with hypoxia and tumour invasiveness in ACC samples, which indicates a possible role of these proteins in the biological behaviour of this tumour.

miR-206 inhibits liver cancer stem cell expansion by regulating EGFR expression

Liver cancer stem cells (CSCs) are involved in tumorigenesis, progression, drug resistance and recurrence of hepatocellular carcinoma (HCC). However, the underlying mechanism for the propagation of liver cancer stem cells was unclear. Herein, we observed miR-206 expression was reduced in both chemoresistant HCCs and recurrent HCCs from patients. A dramatically decrease of miR-206 was detected in cluster of differentiation 133 (CD133) or epithelial cell adhesion molecule (EpCAM)-positive liver CSCs and in CSC-enriched hepatoma spheres. Functional studies revealed that a forced expression of miR-206 inhibited liver CSCs expansion by suppressing the dedifferentiation of hepatoma cells and attenuating the self-renewal of liver CSCs. Mechanistically, bioinformatic and luciferase reporter analysis identified epidermal growth factor receptor (EGFR) as a direct target of miR-206. Moreover, miR-206 downregulated the expression of EGFR in liver CSCs. There was a significant inverse correlation between miR-206 and EGFR mRNA expression in HCC samples. Special EGFR inhibitor Gefitinib abolished the discrepancy in liver CSC proportion and the self-renewal capacity between miR-206 overexpression hepatoma cells and control cells, which further confirmed that EGFR was required in miR-206-inhibited liver CSCs expansion. Conclusion: miR-206 could suppress HCC cell dedifferentiation and liver CSCs expansion by targeting EGFR signaling.

Kinetic analysis of HER2-binding ABY-025 Affibody molecule using dynamic PET in patients with metastatic breast cancer

Background

High expression of human epidermal growth factor receptor type 2 (HER2) represents an aggressive subtype of breast cancer. Anti-HER2 treatment requires a theragnostic approach wherein sufficiently high receptor expression in biopsy material is mandatory. Heterogeneity and discordance of HER2 expression between primary tumour and metastases, as well as within a lesion, present a complication for the treatment and require multiple biopsies. Molecular imaging using the HER2-targeting Affibody peptide ABY-025 radiolabelled with ⁶⁸Ga-gallium for PET/CT is currently under investigation as a non-invasive tool for whole-body evaluation of metastatic HER2 expression. Initial studies demonstrated a high correlation between ⁶⁸Ga-ABY-025 standardized uptake values (SUVs) and histopathology. However, detecting small liver lesions might be compromised by high background uptake. This study aimed to explore the applicability of kinetic modelling and parametric image analysis for absolute quantification of ⁶⁸Ga-ABY-025 uptake and HER2-receptor expression and how that relates to static SUVs.

Methods

Dynamic ⁶⁸Ga-ABY-025 PET of the upper abdomen was performed 0-45 min post-injection in 16 patients with metastatic breast cancer. Five patients underwent two examinations to test reproducibility. Parametric images of tracer delivery (K₁) and irreversible binding (K_i) were created with an irreversible two-tissue compartment model and Patlak graphical analysis using an image-derived input function from the descending aorta. A volume of interest (VOI)-based analysis was performed to validate parametric images. SUVs were calculated from 2 h and 4 h post-injection static whole-body images and compared to K_i.

Results

Characterization of HER2 expression in smaller liver metastases was improved using parametric images. K_i values from parametric images agreed very well with VOI-based gold standard (R² > 0.99, p < 0.001). SUVs of metastases at 2 h and 4 h post-injection were highly correlated with K_i values from both the two-tissue compartment model and Patlak method (R² = 0.87 and 0.95, both p < 0.001). ⁶⁸Ga-ABY-025 PET yielded high test-retest reliability (relative repeatability coefficient for Patlak 30% and for the two-tissue compartment model 47%).

Conclusion

⁶⁸Ga-ABY-025 binding in HER2-positive metastases was well characterized by irreversible two-tissue compartment model wherein K_i highly correlated with SUVs at 2 and 4 h. Dynamic scanning with parametric image formation can be used to evaluate metastatic HER2 expression accurately.

Trastuzumab Emtansine: Mechanisms of Action and Resistance, Clinical Progress, and Beyond

The approval of ado-trastuzumab emtansine (T-DM1) for clinical use represented a turning point both in HER2-positive breast cancer treatment and antibody-drug conjugate (ADC) technology. T-DM1 has proved its value and effectiveness in advanced metastatic disease as well as in the adjuvant setting. However, its therapeutic potential extends beyond the treatment of breast cancer. Around 100 clinical trials have evaluated or are studying different aspects of T-DM1, such as its role in other HER2 malignancies, rational combinations with immunotherapy, or its function in brain metastasis. Conceptually, many lessons can be learned from this ADC. Understanding its mechanisms of action and the molecular basis underlying resistance to T-DM1 may be relevant to comprehend resistances raised to other ADCs and identify pitfalls that may be overcome.