Next-generation EGFR/HER tyrosine kinase inhibitors for the treatment of patients with non-small-cell lung cancer harboring EGFR mutations: a review of the evidence

Epidermal Growth Factor Receptor Inhibitors in Glioblastoma: Current Status and Future Possibilities

Glioblastoma, a grade 4 glioma as per the World Health Organization, poses a challenge in adult primary brain tumor management despite advanced surgical techniques and multimodal therapies. This review delves into the potential of targeting epidermal growth factor receptor (EGFR) with small-molecule inhibitors and antibodies as a treatment strategy. EGFR, a mutationally active receptor tyrosine kinase in over 50% of glioblastoma cases, features variants like EGFRvIII, EGFRvII and missense mutations, necessitating a deep understanding of their structures and signaling pathways. Although EGFR inhibitors have demonstrated efficacy in other cancers, their application in glioblastoma is hindered by blood-brain barrier penetration and intrinsic resistance. The evolving realm of nanodrugs and convection-enhanced delivery offers promise in ensuring precise drug delivery to the brain. Critical to success is the identification of glioblastoma patient populations that benefit from EGFR inhibitors. Tools like radiolabeled anti-EGFR antibody 806i facilitate the visualization of EGFR conformations, aiding in tailored treatment selection. Recognizing the synergistic potential of combination therapies with downstream targets like mTOR, PI3k, and HDACs is pivotal for enhancing EGFR inhibitor efficacy. In conclusion, the era of precision oncology holds promise for targeting EGFR in glioblastoma, contingent on tailored treatments, effective blood-brain barrier navigation, and the exploration of synergistic therapies.

microRNA-184 in the landscape of human malignancies: a review to roles and clinical significance

MicroRNAs (miRNAs) are a class of non-coding RNAs (ncRNAs) with a short length of 19-22 nucleotides. miRNAs are posttranscriptional regulators of gene expression involved in various biological processes like cell growth, apoptosis, and angiogenesis. miR-184 is a well-studied miRNA, for which most studies report its downregulation in cancer cells and tissues and experiments support its role as a tumor suppressor inhibiting malignant biological behaviors of cancer cells in vitro and in vivo. To exert its functions, miR-184 affects some signaling pathways involved in tumorigenesis like Wnt and β-catenin, and AKT/mTORC1 pathway, oncogenic factors (e.g., c-Myc) or apoptotic proteins, such as Bcl-2. Interestingly, clinical investigations have shown miR-184 with good performance as a prognostic/diagnostic biomarker for various cancers. Additionally, exogenous miR-184 in cell and xenograft animal studies suggest it as a therapeutic anticancer target. In this review, we outline the studies that evaluated the roles of miR-184 in tumorigenesis as well as its clinical significance.

Sanikovich V, S. Rusanov A, N. Pirogova Y, Boroda A, Rozhkov A, Kemfang Ngowa JD, N. Bagmet L, I. Sekacheva M. Angiogenesis in Lung Cancer: Understanding the Roles of Growth Factors

Research has shown the role of growth factors in lung cancer angiogenesis. Angiogenesis promotes lung cancer progression by stimulating tumor growth, enhancing tumor invasion, contributing to metastasis, and modifying immune system responses within the tumor microenvironment. As a result, new treatment techniques based on the anti-angiogenic characteristics of compounds have been developed. These compounds selectively block the growth factors themselves, their receptors, or the downstream signaling pathways activated by these growth factors. The EGF and VEGF families are the primary targets in this approach, and several studies are being conducted to propose anti-angiogenic drugs that are increasingly suitable for the treatment of lung cancer, either as monotherapy or as combined therapy. The efficacy of the results are encouraging, but caution must be placed on the higher risk of toxicity, outlining the importance of personalized follow-up in the management of these patients.

EGFR-T790M Mutation-Derived Interactome Rerouted EGFR Translocation Contributing to Gefitinib Resistance in Non-Small Cell Lung Cancer

Secondary mutation, T790M, conferring tyrosine kinase inhibitors (TKIs) resistance beyond oncogenic epidermal growth factor receptor (EGFR) mutations presents a challenging unmet need. Although TKI-resistant mechanisms are intensively investigated, the underlying responses of cancer cells adapting drug perturbation are largely unknown. To illuminate the molecular basis linking acquired mutation to TKI resistance, affinity purification coupled mass spectrometry was adopted to dissect EGFR interactome in TKI-sensitive and TKI-resistant non-small cell lung cancer cells. The analysis revealed TKI-resistant EGFR-mutant interactome allocated in diverse subcellular distribution and enriched in endocytic trafficking, in which gefitinib intervention activated autophagy-mediated EGFR degradation and thus autophagy inhibition elevated gefitinib susceptibility. Alternatively, gefitinib prompted TKI-sensitive EGFR translocating toward cell periphery through Rab7 ubiquitination which may favor efficacy to TKIs suppression. This study revealed that T790M mutation rewired EGFR interactome that guided EGFR to autophagy-mediated degradation to escape treatment, suggesting that combination therapy with TKI and autophagy inhibitor may overcome acquired resistance in non-small cell lung cancer.

Dual kinase inhibitor for EGFR mutants and ErbB2 limit breast cancer

Mutations in the epidermal growth factor receptor (EGFR) have been found in more than 10% of non-small cell lung cancer (NSCLC) patients in North America. The vast majority of these differences are L858R point mutations in Exon 21. Currently, monoclonal antibodies directed against the extracellular domain of EGFR or small molecule/tyrosine kinase inhibitors (TKI) are the stalwarts of NSCLC therapy. Resistance, however, gradually develops because of the T790 mutation towards first and second generation TKIs. The third generation TKI AZD9291 (Osimertinib) has a high affinity for both activating and the acquired resistant mutation (T790 M) in EGFR, with a low affinity towards wild-type EGFR. Recent research, however, suggests that the EGFR (C797S) mutation in the tyrosine kinase domain is a likely cause of resistance to AZD9291. Another significant transformation mechanism associated with this resistance is erbB2 amplification. Our laboratory has developed a small kinase inhibitor, ER121 (MW: ∼500), that inhibits the erbB2/HER2 tyrosine kinases in addition to the EGFR C797S mutations. We have identified a TKI, ER121 targeting the mutant EGFR(T790 M). Using in vitro and in vivo models, examined the efficacy of ER121 on mutant EGFR cell lines. This has enabled us to establish that ER121 is well tolerated when administered orally and produces significant inhibitory activity against human cancers generated by mutant EGFR and amplified ErbB2.

Clinical updates on tyrosine kinase inhibitors in HER2-positive breast cancer

Breast cancer (BC) is caused by epigenetic modifications and genetic heterogeneity and exhibits various histological feature. HER2+ (Human epidermal growth factor receptor 2) is a more aggressive type of breast cancer, diagnosis and prognosis are difficult for HER2+ BC. Anti-HER2+ inhibitors have been effectively used for patient treatment. High mortality rate is reported in HER2+ BC, due to availability of limited therapeutic options. Despite advances in systemic medications to treat metastatic breast cancer (MBC), HER2-positive MBC is still challenging for patients and treating clinicians. The clinical characteristics of the disease have changed after treatment with HER2-targeted therapy. Various types of Tyrosine kinase inhibitors (TKIs) have been developed to treat patients with HER2+ BC including afatinib, lapatinib, neratinib, tucatinib, and pyrotinib, have been developed as HER2-targeted therapies. The antibody-drug conjugates adotrastuzumab, emtansine, famtrastuzumab, and deruxtecan, as well as the anti-HER2 monoclonal antibody pertuzumab are used in both early-stage and metastatic situations, either alone or in conjunction with chemotherapy and other HER2-targeting therapies. The emergence of drug resistance in anti-HER2 therapies has been observed. To overcome drug resistance and limited efficacy in current treatment options, nano formulations can be used in patients with HER2+ BC treatment. Anti-HER2 ligands can be used in various nano formulations to target HER2 receptors. Here we will discuss, targeted TKIs in patients with HER2+ BC, clinical studies of HER2+ targeted TKIs, mechanisms of resistance to HER2-directed therapies with new implications of TKIs in HER2+ MBC (metastatic breast cancer) and anti-HER2 ligand in various nano formulations to target HER2 receptors.

EGFR, the Lazarus target for precision oncology in glioblastoma

The Lazarus effect is a rare condition that happens when someone seemingly dead shows signs of life. The epidermal growth factor receptor (EGFR) represents a target in the fatal neoplasm glioblastoma (GBM) that through a series of negative clinical trials has prompted a vocal subset of the neuro-oncology community to declare this target dead. However, an argument can be made that the core tenets of precision oncology were overlooked in the initial clinical enthusiasm over EGFR as a therapeutic target in GBM. Namely, the wrong drugs were tested on the wrong patients at the wrong time. Furthermore, new insights into the biology of EGFR in GBM vis-à-vis other EGFR-driven neoplasms, such as non-small cell lung cancer, and development of novel GBM-specific EGFR therapeutics resurrects this target for future studies. Here, we will examine the distinct EGFR biology in GBM, how it exacerbates the challenge of treating a CNS neoplasm, how these unique challenges have influenced past and present EGFR-targeted therapeutic design and clinical trials, and what adjustments are needed to therapeutically exploit EGFR in this devastating disease.

Design, synthesis and biological evaluation of novel macrocyclic derivatives bearing aniline pyrimidine scaffolds as EGFR-TKIs

Based on EGFR-TKI Osimertinib as lead compound, a series of novel macrocyclic derivatives bearing aniline pyrimidine scaffolds were designed and synthesized by macrocyclization. Their structures were identified by ¹H NMR, ¹³C NMR, ¹⁹F NMR and HRMS. The pharmacological activities of the target compounds were tested and the preliminary structure-activity relationship was discussed. Among them, 17-membered ring compound H1 displayed the best inhibitory activities against EGFR^L858R/T790M and EGFR^{d746-750/T790M} with IC₅₀ value of 2.92 nM and 0.34 nM, respectively. Exhilaratingly, 17-membered ring compound H7 possessed the most potent antiproliferative activity against BaF3-EGFR^del19/T790M cell lines (IC₅₀ = 0.035 µm), which rivaled that of Osimertinib (IC₅₀ = 0.033 µm).

Oncogenic dependency on STAT3 serine phosphorylation in KRAS mutant lung cancer

The oncogenic potential of the latent transcription factor signal transducer and activator of transcription (STAT)3 in many human cancers, including lung cancer, has been largely attributed to its nuclear activity as a tyrosine-phosphorylated (pY₇₀₅ site) transcription factor. By contrast, an alternate mitochondrial pool of serine phosphorylated (pS₇₂₇ site) STAT3 has been shown to promote tumourigenesis by regulating metabolic processes, although this has been reported in only a restricted number of mutant RAS-addicted neoplasms. Therefore, the involvement of STAT3 serine phosphorylation in the pathogenesis of most cancer types, including mutant KRAS lung adenocarcinoma (LAC), is unknown. Here, we demonstrate that LAC is suppressed in oncogenic Kras^G12D-driven mouse models engineered for pS₇₂₇-STAT3 deficiency. The proliferative potential of the transformed Kras^G12D lung epithelium, and mutant KRAS human LAC cells, was significantly reduced upon pS₇₂₇-STAT3 deficiency. Notably, we uncover the multifaceted capacity of constitutive pS₇₂₇-STAT3 to metabolically reprogramme LAC cells towards a hyper-proliferative state by regulating nuclear and mitochondrial (mt) gene transcription, the latter via the mtDNA transcription factor, TFAM. Collectively, our findings reveal an obligate requirement for the transcriptional activity of pS₇₂₇-STAT3 in mutant KRAS-driven LAC with potential to guide future therapeutic targeting approaches.

Identification of Phospho-Tyrosine Targets as a Strategy for the Treatment of Esophageal Adenocarcinoma Cells

Introduction

Esophageal cancer (EC) is an aggressive cancer type that is increasing at a high rate in the US and worldwide. Extensive sequencing of EC specimens has shown that there are no consistent driver mutations that can impact treatment strategies. The goal of this study was to identify activated tyrosine kinase receptors (TKRs) in EC samples as potential targets in the treatment of EC.

Methods

Activated tyrosine kinase receptors were detected using a dot-blot array for human TK receptors. Human esophageal cancer cell lines were transplanted into immunocompromised mice, and tumor xenografts were subjected to tyrosine kinase inhibitors based on the dot-blot array data.

Results

Using the OE33 esophageal cancer cell line, we identified activated EGF receptor (EGFR), as well as ErbB2 and ErbB3. Treatment of this cell line with erlotinib, a specific inhibitor of EGFR, did not impact the growth of this tumor cell line. Treating the OE33 cell line with afatinib, a pan-EGFR family inhibitor resulted in the growth inhibition of OE33, indicating that the ErbB2 and ErbB3 receptors were contributing to tumor cell proliferation. Afatinib treatment of mice growing OE33 tumors inhibited growth of the OE33 tumor cells.

Discussion

Activated tyrosine kinase receptors were readily detected in both cancer cell lines and human esophageal cancer samples. By identifying the activated receptors and then using the appropriate tyrosine kinase inhibitors, we can block tumor growth in vitro and in animal xenografts. We propose that identifying and targeting activated TKRs can be used as a personalized EC tumor treatment strategy.

ARIH1 signaling promotes anti-tumor immunity by targeting PD-L1 for proteasomal degradation

Cancer expression of PD-L1 suppresses anti-tumor immunity. PD-L1 has emerged as a remarkable therapeutic target. However, the regulation of PD-L1 degradation is not understood. Here, we identify several compounds as inducers of PD-L1 degradation using a high-throughput drug screen. We find EGFR inhibitors promote PD-L1 ubiquitination and proteasomal degradation following GSK3α-mediated phosphorylation of Ser279/Ser283. We identify ARIH1 as the E3 ubiquitin ligase responsible for targeting PD-L1 to degradation. Overexpression of ARIH1 suppresses tumor growth and promotes cytotoxic T cell activation in wild-type, but not in immunocompromised mice, highlighting the role of ARIH1 in anti-tumor immunity. Moreover, combining EGFR inhibitor ES-072 with anti-CTLA4 immunotherapy results in an additive effect on both tumor growth and cytotoxic T cell activation. Our results delineate a mechanism of PD-L1 degradation and cancer escape from immunity via EGFR-GSK3α-ARIH1 signaling and suggest GSK3α and ARIH1 might be potential drug targets to boost anti-tumor immunity and enhance immunotherapies.

In vitro and ex vivo anti‑tumor effect and mechanism of Tucatinib in leukemia stem cells and ABCG2‑overexpressing leukemia cells

Leukemia stem cells (LSCs), which evade standard chemotherapy, may lead to chemoresistance and disease relapse. The overexpression of ATP-binding cassette subfamily G member 2 (ABCG2) is an important determinant of drug resistance in LSCs and it can serve as a marker for LSCs. Targeting ABCG2 is a potential strategy to selectively treat and eradicate LSCs, and, hence, improve leukemia therapy. Tucatinib (Irbinitinib) is a novel tyrosine kinase inhibitor, targeting ErbB family member HER2, and was approved by the Food and Drug Administration in April 2020, and in Switzerland in May 2020 for the treatment of HER2-positive breast cancer. In the present study, the results demonstrated that tucatinib significantly improved the efficacy of conventional chemotherapeutic agents in ABCG2-overexpressing leukemia cells and primary leukemia blast cells, derived from patients with leukemia. In addition, tucatinib markedly decreased the proportion of leukemia stem cell-like side population (SP) cells. In SP cells, isolated from leukemia cells, the intracellular accumulation of Hoechst 33342, which is an ABCG2 substrate, was significantly elevated by tucatinib. Furthermore, tucatinib notably inhibited the efflux of [³H]-mitoxantrone and, hence, there was a higher level of [³H]-mitoxantrone in the HL60/ABCG2 cell line. The result from the ATPase assay revealed that tucatinib may interact with the drug substrate-binding site and stimulated ATPase activity of ABCG2. However, the protein expression level and cellular location of ABCG2 were not affected by tucatinib treatment. Taken together, these data suggested that tucatinib could sensitize conventional chemotherapeutic agents, in ABCG2-overexpressing leukemia cells and LSCs, by blocking the pump function of the ABCG2 protein. The present study revealed that combined treatment with tucatinib and conventional cytotoxic agents could be a potential therapeutic strategy in ABCG2-positive leukemia.

Advances in targeting EGFR allosteric site as anti-NSCLC therapy to overcome the drug resistance

BACKGROUND

The epidermal growth factor receptor (EGFR) inhibitors represent the first-line therapy regimen for non-small cell lung cancer (NSCLC). Most of these inhibitors target the ATP-site to stop the aggressive development of NSCLC. Stabilization of the ATP-binding on EGFR is difficult due to autophosphorylation of the EGFR domain. This leads to activation of nonintrinsic influence of the tumor microenvironment and expression of anti-apoptotic pathways and drug resistance.

METHODS

The NSCLC related literature search was carried out using online databases such as Scopus, Web of Sciences, PubMed, Protein Data Bank and UniPort for the last ten years and selected articles are referred for discussion in this review.

RESULTS

To overcome the problem of mutations in NSCLC, the allosteric site of EGFR was targeted, which shows significant therapeutic outcome without causing resistance. Compounds like EAI001, EAI045 JBJ-04-125-02, DDC4002 and a series of small molecules with an affinity towards the EGFR allosteric site are reported and are under the investigational stage. These compounds are categorized under fourth-generation anti-NSCLC agents.

CONCLUSION

Composition of this review highlights the advantage of inhibiting allosteric site in the EGFRTK receptor domains and presents a comparative analysis of the new fourth-generation anti-NSCLC agents to overcome the drug resistance.

Fluoropyrimidin-2,4-dihydroxy-5-isopropylbenzamides as antitumor agents against CRC and NSCLC cancer cells

A major cause of failure of therapy in patients with non-small cell lung cancer (NSCLC) is development of acquired drug resistance leading to tumor recurrence and disease progression. In addition to the development of new generations of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), different molecular targets may provide opportunities to improve the therapeutic outcomes. In this study, we utilized the core structure 5-fluorouracil (5-FU) or tegafur, a 5-FU prodrug combined through different linkers with resorcinol to generate a series of fluoropyrimidin-2,4-dihydroxy-5-isopropylbenzamides which inhibit potent Heat Shock Protein 90 (HSP90). These compounds were found to show significant antiproliferative activity in colorectal cancer (CRC) HCT116 and NSCLC A549, H460, and H1975 (EGFR L858R/T790 M double mutation) cells. Compound 12c, developed by molecular docking analysis and enzymatic assays exhibits promising inhibitory activity of HSP90. This compound, 12c shows the most potent HSP90 inhibitory activity with an IC₅₀ value of 27.8 ± 4.4 nM, superior to that of reference compounds AUY-922 (Luminespib) and BIIB021 whose IC₅₀ values are 43.0 ± 0.9 nM and 56.8 ± 4.0 nM respectively. This strong HSP90 inhibitory activity of 12c leads to rapid degradation of client proteins EGFR and Akt in NSCLC cells. In addition, 12c induces significant accumulation of a sub-G1 phase population in parallel with apoptosis by showing activated caspase-3, -8 and -9 and PARP induction. These results provide a new strategy for development of novel HSP90 inhibitors for cancer treatment.

Serum CRIPTO does not confer drug resistance against osimertinib but is an indicator of tumor burden in non-small cell lung cancer

BACKGROUND

Adenocarcinoma is the most common subtype of non-small cell lung cancer (NSCLC) and often harbors oncogenic driver mutations in the epidermal growth factor receptor (EGFR). Osimertinib (AZD9291), a third generation EGFR TKI, has replaced earlier generation EGFR TKIs for first line treatment of EGFR mutant lung cancer due to its improved overall survival, longer progression free survival, and better tolerability compared to earlier generation inhibitors. However, like earlier generation EGFR TKIs, only about two thirds of patients respond, indicating an unknown mechanism of intrinsic resistance for the non-responders. We previously identified overexpression of CRIPTO as a potential mechanism of intrinsic resistance to EGFR TKIs of first and second generation.

OBJECTIVE

To determine if CRIPTO could promote drug resistance against the third generation EGFR-TKIs osimertinib. We also wanted to investigate whether this resistance was conferred by both membrane bound and secreted CRIPTO. Finally, we wanted to explore the potential of secreted CRIPTO as a non-invasive biomarker for EGFR-TKI resistance.

MATERIALS AND METHODS

HCC827 and H1975, EGFR mutant non-small cell lung carcinoma (NSCLC) cell lines, were transfected with wildtype CRIPTO, two secreted variants of CRIPTO, a membrane only version of CRIPTO, and the mock backbone vector as the control. Western blotting, immunoprecipitation, and in vitro viability experiments were performed. In vivo work was carried out in athymic nude mice; 2 × 10⁶ CRIPTO overexpressing HCC827 cells were implanted per mouse. EGFR mutant NSCLC patient blood samples were collected before treatment with and EGFR-TKI, during response while on treatment, and at progression while on treatment.

RESULTS

Although both membrane bound and secreted CRIPTO forms were able to activate downstream pathways such as SRC, CRIPTO was unable to elicit resistance towards osimertinib in vitro or in vivo. CRIPTO serum levels in mice were higher in larger xenograft tumors. Furthermore, CRIPTO serum levels were higher in patients with progressing lung cancer when compared to their CRIPTO serum levels during EGFR-TKI response.

CONCLUSIONS

CRIPTO does not cause resistance against third generation EGFR-TKI osimertinib. CRIPTO levels in serum might be a potentially useful biomarker for tumor burden in NSCLC patients.

Comprehensive review of targeted therapy for colorectal cancer

Colorectal cancer (CRC) is among the most lethal and prevalent malignancies in the world and was responsible for nearly 881,000 cancer-related deaths in 2018. Surgery and chemotherapy have long been the first choices for cancer patients. However, the prognosis of CRC has never been satisfying, especially for patients with metastatic lesions. Targeted therapy is a new optional approach that has successfully prolonged overall survival for CRC patients. Following successes with the anti-EGFR (epidermal growth factor receptor) agent cetuximab and the anti-angiogenesis agent bevacizumab, new agents blocking different critical pathways as well as immune checkpoints are emerging at an unprecedented rate. Guidelines worldwide are currently updating the recommended targeted drugs on the basis of the increasing number of high-quality clinical trials. This review provides an overview of existing CRC-targeted agents and their underlying mechanisms, as well as a discussion of their limitations and future trends.

The synergistic inhibitory effect of combining therapies targeting EGFR and mitochondria in sarcomas

Our group previously demonstrated that sarcoma cell lines were insensitive to epidermal growth factor receptor (EGFR) inhibitor gefitinib monotherapy. PENAO, an anti-tumour metabolic compound created in our laboratory, is currently in clinical trials. Considering the positive regulation of tumour energy production by both the EGFR signalling and tumour metabolism pathways, this study aimed to investigate the effect and mechanisms of combination therapy using gefitinib and PENAO in sarcoma cell lines in vitro and in vivo.

PENAO monotherapy reduced proliferation in 12 sarcoma cell lines. Combining gefitinib and PENAO resulted in synergistic inhibition in both a time- and dose-dependent manner in 3 sarcoma cell lines with less prominent monotherapy effects. Combined treatment significantly enhanced cell death and perturbed mitochondrial function. In vivo combination therapy with PENAO and gefitinib was non-toxic to mice and significantly delayed tumour growth and prolonged survival. At 20 days after treatment, tumours from the combination treated mice were significantly smaller than those from untreated and single drug treated mice. The survival curves also showed significant difference across and between groups.

The combination of PENAO and gefitinib in vitro and in vivo, shows promise as a treatment pathway in this poor outcome tumour.

miR-425 regulates cell proliferation, migration and apoptosis by targeting AMPH-1 in non-small-cell lung cancer

BACKGROUND

MicroRNAs (miRNAs) have been proved to act as vital roles on non-small-cell lung cancer (NSCLC), and miR-425 has been proven to serve an important function in several tumors. However, the functional role of miR-425 on NSCLC is still unclear.

METHODS

The mRNA and protein expression of miR-425 and AMPH-1 were determined by qRT-PCR and western blot analysis, respectively. NSCLC cells (SK-MES-1 and A549) proliferation and migration were measured by CCK-8 and transwell assay, respectively. Cell apoptosis was assessed by flow cytometry and western blotting, In addition, luciferase reporter assay was carried out to confirm the direct targeting of AMPH-1 by miR-425. Xenograft experiments were performed to observe the tumorigenesis of miR-425 in vivo.

RESULTS

The results showed that miR-425 was overexpressed and AMPH-1 expression was downregulated in SK-MES-1 and A549 cells. Silencing miR-425 inhibited proliferation, migration and promoted apoptosis of NSCLC cells. Moreover, we proved that miR-425 could target AMPH-1. The expression of AMPH-1was upregulated in A549 with miR-425 inhibitor. Moreover, miR-425 knockdown were less tumorigenic than the control in vivo.

CONCLUSIONS

Taken together, miR-425 could promote the proliferation, invasion and suppress apoptosis by targeting AMPH-1 in NSCLC cells. miR-425/AMPH-1 axis may represent a potential therapeutic strategy or novel prognostic biomarkers to NSCLC.

Targeting Degradation of EGFR through the Allosteric Site Leads to Cancer Cell Detachment-Promoted Death

Targeting epidermal growth factor receptor (EGFR) with tyrosine kinase inhibitors (TKI) has been widely exploited to disrupt aberrant phosphorylation flux in cancer. However, a bottleneck of potent TKIs is the acquisition of drug resistance mutations, secondary effects, and low ability to attenuate tumor progression. We have developed an alternative means of targeting EGFR that relies on protein degradation through two consecutive routes, ultimately leading to cancer cell detachment-related death. We describe furfuryl derivatives of 4-allyl-5-[2-(4-alkoxyphenyl)-quinolin-4-yl]-4H-1,2,4-triazole-3-thiol that bind to and weakly inhibit EGFR tyrosine phosphorylation and induce strong endocytic degradation of the receptor in cancer cells. The compound-promoted depletion of EGFR resulted in the sequestration of non-phosphorylated Bim, which no longer ensured the integrity of the cytoskeleton machinery, as shown by the detachment of cancer cells from the extracellular matrix (ECM). Of particular note, the longer CH₃(CH₂)n chains in the terminal moiety of the anti-EGFR molecules confer higher hydrophobicity in the allosteric site located in the immediate vicinity of the catalytic pocket. Small compounds accelerated and enhanced EGFR and associated proteins degradation during EGF and/or glutamine starvation of cultures, thereby demonstrating high potency in killing cancer cells by simultaneously modulating signaling and metabolic pathways. We propose a plausible mechanism of anti-cancer action by small degraders through the allosteric site of EGFR. Our data represent a rational and promising perspective in the treatment of aggressive tumors.

Comparison of Epidermal Growth Factor Receptor Gene Mutations Identified Using Pleural Effusion and Primary Tumor Tissue Samples in Non-Small Cell Lung Cancer

BACKGROUND

Although the use of pleural effusion samples for epidermal growth factor receptor (EGFR) testing in lung cancer is increasing, the accuracy rate and effectiveness of identifying EGFR mutations using these samples, rather than primary tumor tissue samples, is not established.

MATERIALS AND METHODS

One hundred ninety-two advanced, non-small cell lung cancer patients were enrolled into this study. All patients had primary tumor tissue and corresponding pleural effusion samples, and we employed the Amplification Refractory Mutation System to detect EGFR gene mutations in these samples.

RESULT

The number of EGFR mutations detected in primary tumor tissue and pleural effusion samples was 119 (61.98%) and 113 (58.85%), respectively. The EGFR-mutation rate was significantly higher in female than in male patients, and in adenocarcinoma than in nonadenocarcinoma patients (P=0.000). Single mutations in exons 19 and 21 were the predominant observed mutation type, and the overall concordance rate of EGFR-mutation status between the 192 matched pleural effusion and primary tumor tissue samples was 86.98%.

CONCLUSIONS

We observed a high concordance rate between EGFR mutations identified using primary tumor tissue and corresponding pleural effusion samples by Amplification Refractory Mutation System. Thus, it is likely that pleural effusion sampling from advanced non-small cell lung cancer patients, especially those with adenocarcinoma, may be effective in EGFR-mutation screening.

Comutation and exclusion analysis in human tumors: A tool for cancer biology studies and for rational selection of multitargeted therapeutic approaches

Malignant tumors originate from somatic mutations and other genomic and epigenomic alterations, which lead to loss of control of the cellular circuitry. These alterations present patterns of co-occurrence and mutual exclusivity that can influence prognosis and modify response to drugs, highlighting the need for multitargeted therapies. Studies in this area have generally focused in particular malignancies and considered whole genes instead of specific mutations, ignoring the fact that different alterations in the same gene can have widely different effects. Here, we present a comprehensive analysis of co-dependencies of individual somatic mutations in the whole spectrum of human tumors. Combining multitesting with conditional and expected mutational probabilities, we have discovered rules governing the codependencies of driver and nondriver mutations. We also uncovered pairs and networks of comutations and exclusions, some of them restricted to certain cancer types and others widespread. These pairs and networks are not only of basic but also of clinical interest, and can be of help in the selection of multitargeted antitumor therapies. In this respect, recurrent driver comutations suggest combinations of drugs that might be effective in the clinical setting, while recurrent exclusions indicate combinations unlikely to be useful.

Epidermal Growth Factor Receptor Gene Mutation Status in Primary Lung Adenocarcinoma and Corresponding Bone Metastases

BACKGROUND

The aim of this study was to compare epidermal growth factor receptor (EGFR) mutations between primary tumors and corresponding bone metastases (BMs) in lung adenocarcinoma.

MATERIALS AND METHODS

In total, 115 paired primary lung adenocarcinoma and corresponding BM tumors were analyzed for EGFR mutations by Amplification Refractory Mutation System.

RESULTS

EGFR mutations were detected in 61 primary lung adenocarcinomas (53.04%) and in 67 corresponding metastases (58.26%), respectively. The EGFR mutation rate was significantly higher in female and in never-smoker patients. The consistency of EGFR mutations between the 115 matched BMs and primary tumor tissue samples reached to 80.87%, and the disparity was 19.13%. Mutations in exons 19 (19-del) and 21 (point mutation L858R) were the predominant mutation type.

CONCLUSIONS

The concordance rate demonstrated the feasibility of EGFR mutations in corresponding metastases using Amplification Refractory Mutation System when the primary tumor tissue is unavailable in the lung adenocarcinoma patients, and the inconsistency indicates that corresponding metastasis being screened simultaneously with the primary tumor samples may present some supplementary information for the patients.

Efficacy and adverse events of five targeted agents in the treatment of advanced or metastatic non-small-cell lung cancer: A network meta-analysis of nine eligible randomized controlled trials involving 5,059 patients

Recently, targeted agents were reported to improve overall survival, progression-free survival (PFS), response rate, and quality of life compared with cytotoxic chemotherapies, which provides hope for the treatment of non-small-cell lung cancer (NSCLC). The network meta-analysis is applied to compare the efficacies and adverse events of five targeted agents (erlotinib, gefitinib, vandetanib, dacomitinib, and icotinib) for advanced or metastatic NSCLC. Nine eligible randomized controlled trials from PubMed and Cochrane Library database were included. Weighted mean difference, odds ratio, and surface under the cumulative ranking curve (SUCRA) values were evaluated for the efficacy and adverse events of the five targeted agents in the treatment of NSCLC. With regard to efficacy, the overall response rate (ORR) of advanced or metastatic NSCLC patients treated with gefitinib was relatively higher than those treated with placebo. Compared with patients treated with placebo, the disease control rate (DCR) of patients treated with erlotinib and with gefitinib was relatively higher. Furthermore, in terms of PFS and DCR, the SUCRA value of icotinib was the highest among the five targeted drugs. With regard to ORR, the SUCRA value of gefitinib was the highest among the five targeted drugs. In terms of fatigue, rash, and cough, erlotinib had the lowest SUCRA value, whereas vandetanib exhibited the lowest SUCRA value in terms of diarrhea. Our study suggests that the efficacies of gefitinib and icotinib for advanced or metastatic NSCLC were comparatively better, whereas the toxicities of erlotinib and vandetanib were relatively greater.

Molecular mechanisms of the juvenile form of Batten disease: important role of MAPK signaling pathways (ERK1/ERK2, JNK and p38) in pathogenesis of the malady

Background

Mutations in the CLN3 gene lead to so far an incurable juvenile-onset neuronal ceroid lipofuscinosis (JNCL) or Batten disease that starts at the age of 4–6 years with a progressive retinopathy leading to blindness. Motor disturbances, epilepsy and dementia manifest during several following years. Most JNCL patients carry the same 1.02-kb deletion in the CLN3 gene, encoding an unusual transmembrane protein, CLN3 or battenin.

Results

Based on data of genome-wide expression profiling in CLN3 patients with different rate of the disease progression [Mol. Med., 2011, 17: 1253–1261] and our bioinformatic analysis of battenin protein-protein interactions in neurons we propose that CLN3 can function as a molecular chaperone for some plasma membrane proteins, being crucially important for their correct folding in endoplasmic reticulum. Changes in spatial structure of these membrane proteins lead to transactivation of the located nearby receptors. Particularly, CLN3 interacts with a subunit of Na/K ATPase ATP1A1 which changes its conformation and activates the adjacent epidermal growth factor receptor (EGFR). As a result, a large amount of erroneously activated EGFR generates MAPK signal cascades (ERK1/ERK2, JNKs and p38) from cell surface eventually causing neurons’ death.

Conclusions

Molecular mechanism of the juvenile form of Batten disease (JNCL), which is based on the excessive activation of signaling cascades in a time of the radical increase of neuronal membranes’ area in the growing brain, have been proposed and substantiated. The primary cause of this phenomenon is the defective function of the CLN3 protein that could not act properly as molecular chaperone for some plasma membrane proteins in the endoplasmic reticulum. The incorrect three-dimensional structure of at least one such protein, ATP1A1, leads to unregulated spontaneous and repetitive activation of the SRC kinase that transactivates EGFR with the subsequent uncontrolled launch of various MAPK cascades. Possible ways of treatment of patients with JNCL have been suggested.

Reviewers

This article was reviewed by Konstantinos Lefkimmiatis, Eugene Koonin and Vladimir Poroikov.

A CARP-1 functional mimetic compound is synergistic with BRAF-targeting in non-small cell lung cancers

Non-small cell lung cancers (NSCLC) account for 85% of all lung cancers, and the epidermal growth factor receptor (EGFR) is highly expressed or activated in many NSCLC that permit use of EGFR tyrosine kinase inhibitors (TKIs) as frontline therapies. Resistance to EGFR TKIs eventually develops that necessitates development of improved and effective therapeutics. CARP-1/CCAR1 is an effector of apoptosis by Doxorubicin, Etoposide, or Gefitinib, while CARP-1 functional mimetic (CFM) compounds bind with CARP-1, and stimulate CARP-1 expression and apoptosis. To test whether CFMs would inhibit TKI-resistant NSCLCs, we first generated and characterized TKI-resistant NSCLC cells. The GI₅₀ dose of Erlotinib for parental and Erlotinib-resistant HCC827 cells was ∼0.1 μM and ≥15 μM, respectively. While Rociletinib or Ocimertinib inhibited the parental H1975 cells with GI₅₀ doses of ≤0.18 μM, the Ocimertinib-resistant pools of H1975 cells had a GI₅₀ dose of ∼12 μM. The GI₅₀ dose for Rociletinib-resistant H1975 sublines ranged from 4.5-8.0 μM. CFM-4 and its novel analog CFM-4.16 attenuated growth of the parental and TKI-resistant NSCLC cells. CFMs activated p38/JNKs, inhibited oncogenic cMet and Akt kinases, while CARP-1 depletion blocked NSCLC cell growth inhibition by CFM-4.16 or Erlotinib. CFM-4.16 was synergistic with B-Raf-targeting in NSCLC, triple-negative breast cancer, and renal cancer cells. A nano-lipid formulation (NLF) of CFM-4.16 in combination with Sorafenib elicited a superior growth inhibition of xenografted tumors derived from Rociletinib-resistant H1975 NSCLC cells in part by stimulating CARP-1 and apoptosis. These findings support therapeutic potential of CFM-4.16 together with B-Raf targeting in treatment of TKI-resistant NSCLCs.

MicroRNAs associated with therapy of non-small cell lung cancer

Background & Objective: The incidence of non-small cell lung cancer (NSCLC) has been rising over the past several decades. Despite various therapeutic regimens and modern diagnostic techniques are developed, NSCLC still have an extremely poor prognosis due to drug resistance. Therefore, it is critical to find a novel precise diagnosis and effective treatment approach for NSCLC patients. MicroRNAs (MiRNAs) are a class of 18-25nt non-coding small RNAs, which have been shown to be involved profoundly in the pathogenesis such as cellular proliferation, differentiation, development, apoptosis and tumorigenesis in many human tumors including of NSCLC. We reviewed existing research literature regarding correlations between miRNAs and their target's response to anticancer treatment, and summarized the recent findings between miRNAs and therapy availability in NSCLC.

Targeted therapy with apatinib in a patient with relapsed small cell lung cancer: A case report and literature review

RATIONALE

Small cell lung cancer (SCLC) is a lethal malignancy. Once relapsed, the disease is irreversible and most of the patients will die of cancer aggravation in 1 to 2 months. In the past several decades, little progress has been made in the systemic treatment of SCLC. Apatinib, as a novel small-molecule tyrosine kinase inhibitor specifically targeting the vascular endothelial growth factor receptor 2 (VEGFR2), has achieved progress in treatment of a variety of cancers. However, there has been no report of the targeted therapy with apatinib in SCLC yet.

PATIENT CONCERNS

A 63-year-old man, an ex-smoker, presented with a slight hoarseness and cough. The patient was admitted to our department with a primary diagnosis of SCLC at an extensive stage (ES-SCLC). After 17 months of successful first-, second-, and third-line chemotherapy, the disease eventually became relapsed. Then, apatinib treatment started promptly on demand by the patient and his family.

INTERVENTION

After presenting an informed consent, the patient received apatinib treatment immediately at a dose of 250 mg/day orally.

OUTCOMES

(1) On the 28th day of apatinib therapy, the symptoms of dyspnea and poor appetite of the patient were notably improved. (2) The CT scan taken on the 70th day showed that the pleural effusion in the left lung almost disappeared. (3) The elevated serum neuron-specific enolase (NSE) level was decreased. The patient died of acute respiratory failure on the 172nd day of apatinib treatment. Importantly, the tumor mass did not enlarge obviously during apatinib treatment.

LESSONS

Here, we presented a case with relapsed SCLC who unexpectedly responded to single-agent apatinib treatment. Therefore, this report will shed light on future studies of targeted therapy with apatinib in SCLC at different stages.

Molecularly targeted therapies in cancer: a guide for the nuclear medicine physician

Molecular imaging continues to influence every aspect of cancer care including detection, diagnosis, staging and therapy response assessment. Recent advances in the understanding of cancer biology have prompted the introduction of new targeted therapy approaches. Precision medicine in oncology has led to rapid advances and novel approaches optimizing the use of imaging modalities in cancer care, research and development. This article focuses on the concept of targeted therapy in cancer and the challenges that exist for molecular imaging in cancer care.

A genetic interaction analysis identifies cancer drivers that modify EGFR dependency

In this study, Liao et al. comprehensively investigated how cancer drivers genetically interact. They searched for modifiers of EGFR dependency by performing CRISPR, shRNA, and expression screens in a NSCLC model, and their data provide strong support for the hypothesis that many cancer drivers can substitute for each other in certain contexts.

A large number of cancer drivers have been identified through tumor sequencing efforts, but how they interact and the degree to which they can substitute for each other have not been systematically explored. To comprehensively investigate how cancer drivers genetically interact, we searched for modifiers of epidermal growth factor receptor (EGFR) dependency by performing CRISPR, shRNA, and expression screens in a non-small cell lung cancer (NSCLC) model. We elucidated a broad spectrum of tumor suppressor genes (TSGs) and oncogenes (OGs) that can genetically modify proliferation and survival of cancer cells when EGFR signaling is altered. These include genes already known to mediate EGFR inhibitor resistance as well as many TSGs not previously connected to EGFR and whose biological functions in tumorigenesis are not well understood. We show that mutation of PBRM1, a subunit of the SWI/SNF complex, attenuates the effects of EGFR inhibition in part by sustaining AKT signaling. We also show that mutation of Capicua (CIC), a transcriptional repressor, suppresses the effects of EGFR inhibition by partially restoring the EGFR-promoted gene expression program, including the sustained expression of Ets transcription factors such as ETV1. Together, our data provide strong support for the hypothesis that many cancer drivers can substitute for each other in certain contexts and broaden our understanding of EGFR regulation.

Claudin-5, -7, and -18 suppress proliferation mediated by inhibition of phosphorylation of Akt in human lung squamous cell carcinoma

Abnormal expression of claudin (CLDN) subtypes has been reported in various solid cancers. However, it is unknown which subtype plays a key role in the regulation of proliferation in cancer cells. The expression of CLDN3-5, 7, and 18 in human lung squamous carcinoma tissues was lower than that in normal tissue. Here, we examined which combination of exogenous CLDNs expression inhibits proliferation and the molecular mechanism using human lung squamous RERF-LC-AI cells. Real-time polymerase chain reaction and western blotting showed that CLDN3-5, 7, and 18 are little expressed in RERF-LC-AI cells. In the exogenously transfected cells, CLDN5, 7, and 18 were distributed in the cell-cell contact areas concomitant with ZO-1, a tight junctional scaffolding protein, whereas CLDN3 and 4 were not. Cell proliferation was individually and additively suppressed by CLDN5, 7, and 18. The expression of these CLDNs showed no cytotoxicity compared with mock cells. CLDN5, 7, and 18 increased p21 and decreased cyclin D1, resulting in the suppression of cell cycle G1-S transition. The expression of these CLDNs inhibited phosphorylation of Akt without affecting phosphorylated ERK1/2. Furthermore, these CLDNs inhibited the nuclear localization of Akt and its association with 3-phosphoinositide-dependent protein kinase-1 (PDK1). The suppression of G1-S transition caused by CLDN5, 7, and 18 was rescued by the expression of constitutively active-Akt. We suggest that the reduction of CLDN5, 7, and 18 expression loses the suppressive ability of interaction between PDK1 and Akt and causes sustained phosphorylation of Akt, resulting in the disordered proliferation in lung squamous carcinoma cells.