Targeting c-Myc to overcome acquired resistance of EGFR mutant NSCLC cells to the third generation EGFR tyrosine kinase inhibitor, osimertinib

SNX16 is required for hepatocellular carcinoma survival via modulating the EGFR-AKT signaling pathway

Sorting nexin 16 (SNX16), a pivotal sorting nexin, emerges in tumor progression complexity, fueling research interest. However, SNX16's biological impact and molecular underpinnings in hepatocellular carcinoma (HCC) remain elusive. This study probes SNX16's function, clinical relevance via mRNA, and protein expression in HCC. Overexpression/knockdown assays of SNX16 were employed to elucidate impacts on HCC cell invasion, proliferation, and EMT. Additionally, the study delved into SNX16's regulation of the EGFR-AKT signaling cascade mechanism. SNX16 overexpression in HCC correlates with poor patient survival; enhancing proliferation, migration, invasion, and tumorigenicity, while SNX16 knockdown suppresses these processes. SNX16 downregulation curbs phospho-EGFR, dampening AKT signaling. EGFR suppression counters SNX16-overexpression-induced HCC proliferation, motility, and invasiveness. Our findings delineate SNX16's regulatory role in HCC, implicating it as a prospective therapeutic target.

AXIN1/MYC Axis Mediated the Osimertinib Resistance in EGFR Mutant Non-Small Cell Lung Cancer Cells

Osimertinib, a promising and approved third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), is a standard strategy for EGFR-mutant non-small cell lung cancer (NSCLC) patients. However, developed resistance is unavoidable, which reduces its long-term effectiveness. In this study, RNA sequencing was performed to analyze differentially expressed genes (DEGs). The PrognoScan database and Gene Expression Profiling Interactive Analysis (GEPIA) were used to identify the key genes for clinical prognosis and gene correlation respectively. Protein expression was determined by western blot analysis. Cell viability assay and Ki67 staining were used to evaluate the effect of osimertinib on tumor cells. Finally, we screened out two hub genes, myelocytomatosis oncogene (Myc) and axis inhibition protein 1 (Axin1), upregulated in three osimertinib-resistant cell lines through RNA sequencing and bioinformatics analysis. Next, cell experiment confirmed that expression of C-MYC and AXIN1 were elevated in different EGFR mutant NSCLC cell lines with acquired resistance to osimertinib, compared with their corresponding parental cell lines. Furthermore, we demonstrated that AXIN1 upregulated the expression of C-MYC and mediated the acquired resistance of EGFR mutant NSCLC cells to osimertinib in vitro. In conclusion, AXIN1 affected the sensitivity of EGFR mutant NSCLC to osimertinib via regulating C-MYC expression in vitro. Targeting AXIN1/MYC signaling may be a potential new strategy for overcoming acquired resistance to osimertinib.

Sialyltransferase ST3GAL4 confers osimertinib resistance and offers strategies to overcome resistance in non-small cell lung cancer

The third-generation EGFR-TKI osimertinib is widely used in EGFR-mutated positive non-small cell lung cancer (NSCLC) patients, but drug resistance is inevitable. The currently known mechanisms only explain resistance in a small proportion of patients. For most patients, the mechanism of osimertinib resistance is still unclear, especially for EGFR-independent resistance. Herein, we thoroughly investigated the novel mechanism of osimertinib resistance and treatment strategies. We identified that ST3GAL4, a sialyltransferase, catalyzes terminal glycan sialylation of receptor protein tyrosine kinases, which induces acquired resistance to osimertinib in vitro and in vivo. In addition, ST3GAL4 is generally overexpressed in osimertinib-resistant patients with unknown resistance mechanisms. ST3GAL4 modifies MET glycosylation on N785 with sialylation, which antagonizes K48-related ubiquitin-dependent MET degradation and subsequently activates MET and its downstream proliferation signaling pathways. Meanwhile, ST3GAL4 knockdown or inhibition by brigatinib resensitizes resistant non-small cell lung cancer cells to osimertinib in vitro and in vivo This study suggests that ST3GAL4 can induce acquired resistance to osimertinib, which may be an important EGFR-independent resistance mechanism Furthermore, targeting ST3GAL4 with brigatinib provides new strategies to overcome osimertinib resistance.

DNA topoisomerase II inhibition potentiates osimertinib's therapeutic efficacy in EGFR-mutant non-small cell lung cancer models

Development of effective strategies to manage the inevitable acquired resistance to osimertinib, a third-generation EGFR inhibitor for the treatment of EGFR-mutant (EGFRm) non-small cell lung cancer (NSCLC), is urgently needed. This study reports that DNA topoisomerase II (Topo II) inhibitors, doxorubicin and etoposide, synergistically decreased cell survival, with enhanced induction of DNA damage and apoptosis in osimertinib-resistant cells; suppressed the growth of osimertinib-resistant tumors; and delayed the emergence of osimertinib-acquired resistance. Mechanistically, osimertinib decreased Topo IIα levels in EGFRm NSCLC cells by facilitating FBXW7-mediated proteasomal degradation, resulting in induction of DNA damage; these effects were lost in osimertinib-resistant cell lines that possess elevated levels of Topo IIα. Increased Topo IIα levels were also detected in the majority of tissue samples from patients with NSCLC after relapse from EGFR tyrosine kinase inhibitor treatment. Enforced expression of an ectopic TOP2A gene in sensitive EGFRm NSCLC cells conferred resistance to osimertinib, whereas knockdown of TOP2A in osimertinib-resistant cell lines restored their susceptibility to osimertinib-induced DNA damage and apoptosis. Together, these results reveal an essential role of Topo IIα inhibition in mediating the therapeutic efficacy of osimertinib against EGFRm NSCLC, providing scientific rationale for targeting Topo II to manage acquired resistance to osimertinib.

TP53 gain-of-function mutations promote osimertinib resistance via TNF-α-NF-κB signaling in EGFR-mutated lung cancer

EGFR tyrosine kinase inhibitors (TKIs) are effective against EGFR-mutated lung cancer, but tumors eventually develop resistance to these drugs. Although TP53 gain-of-function (GOF) mutations promote carcinogenesis, their effect on EGFR-TKI efficacy has remained unclear. We here established EGFR-mutated lung cancer cell lines that express wild-type (WT) or various mutant p53 proteins with CRISPR-Cas9 technology and found that TP53-GOF mutations promote early development of resistance to the EGFR-TKI osimertinib associated with sustained activation of ERK and expression of c-Myc. Gene expression analysis revealed that osimertinib activates TNF-α-NF-κB signaling specifically in TP53-GOF mutant cells. In such cells, osimertinib promoted interaction of p53 with the NF-κB subunit p65, translocation of the resulting complex to the nucleus and its binding to the TNF promoter, and TNF-α production. Concurrent treatment of TP53-GOF mutant cells with the TNF-α inhibitor infliximab suppressed acquisition of osimertinib resistance as well as restored osimertinib sensitivity in resistant cells in association with attenuation of ERK activation and c-Myc expression. Our findings indicate that induction of TNF-α expression by osimertinib in TP53-GOF mutant cells contributes to the early development of osimertinib resistance, and that TNF-α inhibition may therefore be an effective strategy to overcome such resistance in EGFR-mutant lung cancer with TP53-GOF mutations.

EZH2/G9a interact to mediate drug resistance in non-small-cell lung cancer by regulating the SMAD4/ERK/c-Myc signaling axis

Drug resistance is the leading problem in non-small-cell lung cancer (NSCLC) therapy. The contribution of histone methylation in mediating malignant phenotypes of NSCLC is well known. However, the role of histone methylation in NSCLC drug-resistance mechanisms remains unclear. Here, our data show that EZH2 and G9a, two histone methyltransferases, are involved in the drug resistance of NSCLC. Gene manipulation results indicate that the combination of EZH2 and G9a promotes tumor growth and mediates drug resistance in a complementary manner. Importantly, clinical study demonstrates that co-expression of both enzymes predicts a poor outcome in patients with NSCLC. Mechanistically, G9a and EZH2 interact and promote the silencing of the tumor-suppressor gene SMAD4, activating the ERK/c-Myc signaling pathway. Finally, SU08, a compound targeting both EZH2 and G9a, is demonstrated to sensitize resistant cells to therapeutic drugs by regulating the SMAD4/ERK/c-Myc signaling axis. These findings uncover the resistance mechanism and a strategy for reversing NSCLC drug resistance.

The cell line models to study tyrosine kinase inhibitors in non-small cell lung cancer with mutations in the epidermal growth factor receptor: A scoping review

Non-Small Cell Lung Cancer (NSCLC) represents ∼85% of all lung cancers and ∼15-20% of them are characterized by mutations affecting the Epidermal Growth Factor Receptor (EGFR). For several years now, a class of tyrosine kinase inhibitors was developed, targeting sensitive mutations affecting the EGFR (EGFR-TKIs). To date, the main burden of the TKIs employment is due to the onset of resistance mutations. This scoping review aims to resume the current situation about the cell line models employed for the in vitro evaluation of resistance mechanisms induced by EGFR-TKIs in oncogene-addicted NSCLC. Adenocarcinoma results the most studied NSCLC histotype with the H1650, H1975, HCC827 and PC9 mutated cell lines, while Gefitinib and Osimertinib the most investigated inhibitors. Overall, data collected frame the current advancement of this topic, showing a plethora of approaches pursued to overcome the TKIs resistance, from RNA-mediated strategies to the innovative combination therapies.

Overall signature of acquired KRAS gene changes in advanced non-small cell lung cancer patient with EGFR-TKI resistance

OBJECTIVE

Numerous scattered case studies continue to demonstrate a strong correlation between acquired KRAS mutations and epidermal growth factor receptor-tyrosine kinase inhibitor resistance in non-small cell lung cancer. However, the comprehensive understanding of the KRAS pathway following the failure of epidermal growth factor receptor-tyrosine kinase inhibitor therapy remains limited.

METHODS

We conducted a retrospective evaluation of the next generation sequencing data from 323 patients with advanced non-small cell lung cancer and EGFR-activating mutations after experiencing progression with epidermal growth factor receptor-tyrosine kinase inhibitor therapy. Our analysis specifically focused on the acquired changes to the KRAS gene.

RESULTS

Among the 323 patients with advanced non-small cell lung cancer and EGFR-activating mutations who experienced resistance to epidermal growth factor receptor-tyrosine kinase inhibitor therapy, 14 individuals (4.3%) developed resistance due to acquired KRAS alterations. Of these 14 patients, 10 cases (71.4%) were due to KRAS missense mutations, 1 case (7.2%) was due to KRAS gene fusion and 3 cases (21.4%) were due to KRAS amplification. Notably, we identified one newly demonstrated KRAS gene fusion (KRAS and LMNTD1), one KRAS G13D and one KRAS K117N. The emergence of acquired KRAS alterations was often accompanied by novel mutations and high tumor mutation burden, with TP53, CNKN2A, PIK3CA, MYC, STK11, CDK4, BRCA2 and ERBB2 being the most frequently observed concurrent mutations. The median progression-free survival and overall survival for the 14 patients were 5.2 and 7.3 months, respectively. Acquired KRAS missense variants were associated with significantly worse progression-free survival compared with other KRAS variant subtypes (P < 0.028).

CONCLUSIONS

This study provides significant evidence of the role of acquired KRAS variants in the development of resistance to epidermal growth factor receptor-tyrosine kinase inhibitor therapy. Our results contribute to the growing body of knowledge on the mutational profiles associated with resistance to epidermal growth factor receptor-tyrosine kinase inhibitor treatment. Furthermore, our study highlights the KRAS gene change as a significant mechanism of resistance to epidermal growth factor receptor-tyrosine kinase inhibitor therapy.

MYC expression and fatty acid oxidation in EGFR-TKI acquired resistance

This report expands on our previous research, highlighting a unique inverse correlation between MYC expression in tumor cells and immune cells during the development of EGFR-TKI resistance. It is observed that MYC expression and fatty acid oxidation (FAO) metabolism in tissue-resident memory (TRM) CD8 + T cells are significantly impaired. These findings offer new insights into the mechanisms of TKI resistance. Although the study is preliminary, it suggests caution when interpreting the effectiveness of MYC inhibitors in reversing TKI resistance, especially when immune factors are not considered.

Pharmacological inhibition of MYC to mitigate chemoresistance in preclinical models of squamous cell carcinoma

Rationale: Cisplatin-based chemotherapy is the first-line treatment for late-stage head and neck squamous cell carcinoma (HNSCC). However, resistance to cisplatin has become a major obstacle for effective therapy. Cancer stem cells (CSCs) are critical for tumor initiation, growth, metastasis, and chemoresistance. How to effectively eliminate CSCs and overcome chemoresistance remains a key challenge. Herein, we confirmed that MYC plays critical roles in chemoresistance, and explored targeting MYC to overcome cisplatin resistance in preclinical models. Methods: The roles of MYC in HNSCC cisplatin resistance and cancer stemness were tested in vitro and in vivo. The combined therapeutic efficiency of MYC targeting using the small molecule MYC inhibitor MYCi975 and cisplatin was assessed in a 4‑nitroquinoline 1-oxide-induced model and in a patient-derived xenograft model. Results: MYC was highly-expressed in cisplatin-resistant HNSCC. Targeting MYC using MYCi975 eliminated CSCs, prevented metastasis, and overcame cisplatin resistance. MYCi975 also induced tumor cell-intrinsic immune responses, and promoted CD8+ T cell infiltration. Mechanistically, MYCi975 induced the DNA damage response and activated the cGAS-STING-IRF3 signaling pathway to increase CD8+ T cell-recruiting chemokines. Conclusions: Our findings suggested that targeting MYC might eliminate CSCs, prevent metastasis, and activate antitumor immunity to overcome cisplatin resistance in HNSCC.

Discovery of YS-363 as a highly potent, selective, and orally efficacious EGFR inhibitor

The Epidermal Growth Factor Receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the standard first-line therapy for EGFR-mutated NSCLC. However, long-term clinical treatment often leads to acquired drug resistance, making NSCLC refractory. Therefore, it is essential to design new EGFR inhibitors as potential drugs against NSCLC. This study reports on a novel quinazoline-based compound called YS-363 that acts as a new EGFR inhibitor. YS-363 demonstrated potent inhibition against both wild-type and L858R mutant forms of EGFR with IC50 values of 0.96 nM and 0.67 nM, respectively. Additionally, YS-363 had a reversible inhibitory effect on cellular EGFR signaling, had excellent inhibitory activity on cell proliferation and migration, and induced G0/G1 cell cycle arrest and apoptosis. In xenograft models dependent on EGFR signaling, oral administration of YS-363 substantially suppressed tumor growth by inhibiting this pathway. In summary, YS-363 is a promising selective reversible inhibitor with a novel quinazoline scaffold that can potentially develop more effective anti-lung cancer agents targeting EGFR in patients who have developed resistance to current therapies such as TKIs like gefitinib or erlotinib.

Tackling Osimertinib Resistance in EGFR-Mutant Non-Small Cell Lung Cancer

The current landscape of targeted therapies directed against oncogenic driver alterations in non-small cell lung cancer (NSCLC) is expanding. Patients with EGFR-mutant NSCLC can derive significant benefit from EGFR tyrosine kinase inhibitor (TKI) therapy, including the third-generation EGFR TKI osimertinib. However, invariably, all patients will experience disease progression with this therapy mainly due to the adaptation of cancer cells through primary or secondary molecular mechanisms of resistance. The comprehension and access to tissue and cell-free DNA next-generation sequencing have fueled the development of innovative therapeutic strategies to prevent and overcome resistance to osimertinib in the clinical setting. Herein, we review the biological and clinical implications of molecular mechanisms of osimertinib resistance and the ongoing development of therapeutic strategies to overcome or prevent resistance.

The potential therapeutic regimen for overcoming resistance to osimertinib due to rare mutations in NSCLC

The mechanisms of osimertinib resistance have not been well characterized. We conducted next-generation sequencing to recognize novel resistance mechanism and used cell line-derived xenograft (CDX) and patient-derived xenograft (PDX) models to evaluate the anti-proliferative effects of aspirin in vivo and in vitro. We observed that PIK3CG mutations led to acquired resistance to osimertinib in a patient and further confirmed that both PIK3CG and PIK3CA mutations caused osimertinib resistance. Mechanistically, the expression of PI3Kγ or PI3Kα was up-regulated after PIK3CG or PIK3CA lentivirus transfection, respectively, and which can be effectively suppressed by aspirin. Lastly, our results from in vivo studies indicate that aspirin can reverse osimertinib resistance caused by PIK3CG or PIK3CA mutations in both CDX and PDX models. Herein, we first confirmed that mutations in PIK3CG can lead to resistance to osimertinib, and the combined therapy may be a strategy to reverse PIK3CG/PIK3CA mutation-induced osimertinib resistance.

Genomic characterisation of de novo EGFR copy number gain and its impact on the efficacy of first-line EGFR-tyrosine kinase inhibitors for EGFR mutated non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation generally respond well to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs). However, genomic characterisation of de novo EGFR copy number gain (CNG) and its impact on the efficacy of first-line EGFR-TKIs remains unclear.

METHODS

This multicenter, retrospective and real-world study included two cohorts that enroled EGFR mutant NSCLC patients. EGFR CNG was tested by next-generation sequencing of untreated tissue specimens. Cohort 1 detected the impact of EGFR CNG on first-line EGFR-TKIs treatment, and cohort 2 explored the genomic characterisation.

RESULTS

Cohort 1 enroled 355 patients from four cancer centres between January 2013 and March 2022. The patients were divided into three groups, included the EGFR non-CNG, EGFR CNG, and EGFR uncertain-CNG. No significant difference in progression-free survival (PFS) was found between the three groups (10.0 months vs. 10.8 months vs. 9.9 months, respectively, p = 0.384). Furthermore, the overall response rate was not statistically significant in the EGFR CNG group compared to the EGFR non-CNG or uncertain arm (70.3% vs. 63.2% vs. 54.5%, respectively, p = 0.154). Cohort 2 included 7876 NSCLC patients with 16.4% showing EGFR CNG. Gene mutations such as TP53, IKZF1, RAC1, MYC, MET, CDKN2A/B and alterations of the metabolic-related and ERK signalling pathway were significantly associated with patients with EGFR CNG compared to those without.

CONCLUSIONS

De novo EGFR CNG had no effect on the efficacy of first-line EGFR-TKI treatment in EGFR mutant NSCLC patients, and tumours with EGFR CNG had more complex genomic profiles than those without.

Challenges of EGFR-TKIs in NSCLC and the potential role of herbs and active compounds: From mechanism to clinical practice

Epidermal growth factor receptor (EGFR) mutations are the most common oncogenic driver in non-small cell lung cancer (NSCLC). Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are widely used in the treatment of lung cancer, especially in the first-line treatment of advanced NSCLC, and EGFR-TKIs monotherapy has achieved better efficacy and tolerability compared with standard chemotherapy. However, acquired resistance to EGFR-TKIs and associated adverse events pose a significant obstacle to targeted lung cancer therapy. Therefore, there is an urgent need to seek effective interventions to overcome these limitations. Natural medicines have shown potential therapeutic advantages in reversing acquired resistance to EGFR-TKIs and reducing adverse events, bringing new options and directions for EGFR-TKIs combination therapy. In this paper, we systematically demonstrated the resistance mechanism of EGFR-TKIs, the clinical strategy of each generation of EGFR-TKIs in the synergistic treatment of NSCLC, the treatment-related adverse events of EGFR-TKIs, and the potential role of traditional Chinese medicine in overcoming the resistance and adverse reactions of EGFR-TKIs. Herbs and active compounds have the potential to act synergistically through multiple pathways and multiple mechanisms of overall regulation, combined with targeted therapy, and are expected to be an innovative model for NSCLC treatment.

Optimal therapy for concomitant EGFR and TP53 mutated non-small cell lung cancer: a real-world study

BACKGROUND

Non-small cell cancer (NSCLC) patients with concomitant epidermal growth factor receptor (EGFR) and TP53 mutations have a poor prognosis with the treatment of tyrosine kinase inhibitors (TKIs), and may benefit from a combination regimen preferentially. The present study aims to compare the benefits of EGFR-TKIs and its combination with antiangiogenic drugs or chemotherapy in patients with NSCLC harboring EGFR and TP53 co-mutation in a real-life setting.

METHODS

This retrospective analysis included 124 patients with advanced NSCLC having concomitant EGFR and TP53 mutations, who underwent next-generation sequencing prior to treatment. Patients were classified into the EGFR-TKI group and combination therapy group. The primary end point of this study was progression-free survival (PFS). The Kaplan-Meier (KM) curve was drawn to analyze PFS, and the differences between the groups were compared using the logarithmic rank test. Univariate and multivariate cox regression analysis was performed on the risk factors associated with survival.

RESULTS

The combination group included 72 patients who received the regimen of EGFR-TKIs combined with antiangiogenic drugs or chemotherapy, while the EGFR-TKI monotherapy group included 52 patients treated with TKI only. The median PFS was significantly longer in the combination group than in the EGFR-TKI group (18.0 months; 95% confidence interval [CI]: 12.1-23.9 vs. 7.0 months; 95% CI: 6.1-7.9; p < 0.001) with greater PFS benefit in TP53 exon 4 or 7 mutations subgroup. Subgroup analysis showed a similar trend. The median duration of response was significantly longer in the combination group than in the EGFR-TKI group. Patients with 19 deletions or L858R mutations both achieved a significant PFS benefit with combination therapy versus EGFR-TKI alone.

CONCLUSION

Combination therapy had a higher efficacy than EGFR-TKI alone for patients with NSCLC having concomitant EGFR and TP53 mutations. Future prospective clinical trials are needed to determine the role of combination therapy for this patient population.

The Effect of Citrus aurantium on Non-Small-Cell Lung Cancer: A Research Based on Network and Experimental Pharmacology

Purpose

To screen the main active components of Citrus aurantium through a network pharmacology approach, construct a component-disease target network, explore its molecular mechanism for the treatment of non-small-cell lung cancer (NSCLC), and validate it experimentally.

Methods

The active ingredients in Citrus aurantium and the targets of Citrus aurantium and NSCLC were collected through the Traditional Chinese Medicine Systematic Pharmacology Database and Analysis Platform (TCMSP), GeneCards, and OMIM databases. The protein interaction network was constructed using the STRING database, and the component-disease relationship network graph was analyzed using Cytoscape 3.9.1. The Metascape database can be used for GO and KEGG enrichment analyses. The Kaplan-Meier plotter was applied for overall survival analysis of key targets of Citrus aurantium in the treatment of NSCLC. Real-time PCR (RT-PCR) and Western blotting were used to determine the mRNA and protein levels of key targets of Citrus aurantium for the treatment of NSCLC.

Results

Five active ingredients of Citrus aurantium were screened, and 54 potential targets for the treatment of NSCLC were found, of which the key ingredient was nobiletin and the key targets are TP53, CXCL8, ESR1, PPAR-α, and MMP9. GO and KEGG enrichment analyses indicated that the mechanism of nobiletin in treating NSCLC may be related to the regulation of cancer signaling pathway, phosphatidylinositol-3 kinase (PI3K)/protein kinase B (Akt) signaling pathway, lipid and atherosclerosis signaling pathway, and neurodegenerative signaling pathway. The experimental results showed that nobiletin could inhibit the proliferation of NSCLC cells and upregulate the levels of P53 and PPAR-α and suppress the expression of MMP9 (P < 0.05).

Conclusion

Citrus aurantium can participate in the treatment of NSCLC through multiple targets and pathways.

Therapeutic Targeting of MYC in Head and Neck Squamous Cell Carcinoma

MYC plays critical roles in tumorigenesis and is considered an attractive cancer therapeutic target. Small molecules that directly target MYC and are well tolerated in vivo represent invaluable anti-cancer therapeutic agents. Here, we aimed to investigate the therapeutic effect of MYC inhibitors in head and neck squamous cell carcinoma (HNSCC). The results showed that pharmacological and genetic inhibition of MYC inhibited HNSCC proliferation and migration. MYC inhibitor 975 (MYCi975), inhibited HNSCC growth in both cell line-derived xenograft and syngeneic murine models. MYC inhibition also induced tumor cell-intrinsic immune responses, and promoted CD8⁺ T cell infiltration. Mechanistically, MYC inhibition increased CD8⁺ T cell-recruiting chemokines by inducing the DNA damage related cGAS-STING pathway. High expression of MYC combined with a low level of infiltrated CD8⁺ T cell in HNSCC correlated with poor prognosis. These results suggested the potential of small-molecule MYC inhibitors as anti-cancer therapeutic agents in HNSCC.

Evaluate the Prognosis of MYC/TP53 Comutation in Chinese Patients with EGFR-Positive Advanced NSCLC Using Next-Generation Sequencing: A Retrospective Study

Purpose: The purpose of this study was to investigate the effect of MYC and TP53 comutations on the clinical efficacy of EGFR tyrosine kinase inhibitors (TKIs) in Chinese patients with advanced EGFR-positive nonsmall-cell lung cancer (NSCLC). Patients and methods: Tissue samples and information from 65 patients with advanced NSCLC in Northern Jiangsu People's Hospital were collected and analyzed by next-generation sequencing (NGS). Progression-free survival (PFS) and total survival (OS) were the main endpoints, and the objective response rate (ORR) and disease control rate (DCR) were the secondary endpoints. Result: Among 65 patients, 17 had TP53 and MYC wild-type mutations (WT/WT), 36 had TP53 mutant and MYC wild-type mutations (TP53/WT), and 12 had coexisting MYC/TP53 mutations (MYC/TP53). When 12 patients with MYC/TP53 comutation were compared with the other two groups (TP53/WT, WT/WT), mPFS and mOS are significantly lower than those in the other two groups (mPFS: 4.1 months vs 6.0 months, 12.3 months, HR: 0.769, 95% CI: 4.592-7.608, P  =  .047. mOS: 14.6 months vs 24.1 months, 31.5 months, HR: 3.170, 95% CI: 18.786-31.214, P < .001), and the ORR, DCR of patients with MYC/TP53 comutation was lower than that of the other two groups (ORR, 25% vs 44.4%, 70.6%, P  =  .045. DCR, 58.3% vs 72.2%, 82.4%, P  =  .365). Conclusion: Patients with MYC/TP53 comutations with EGFR-positive advanced NSCLC are more likely to develop drug resistance after early treatment with EGFR-TKIs and have a worse clinical outcome.

Control of cell metabolism by the epidermal growth factor receptor

The epidermal growth factor receptor (EGFR) triggers the activation of many intracellular signals that control cell proliferation, growth, survival, migration, and differentiation. Given its wide expression, EGFR has many functions in development and tissue homeostasis. Some of the cellular outcomes of EGFR signaling involve alterations of specific aspects of cellular metabolism, and alterations of cell metabolism are emerging as driving influences in many physiological and pathophysiological contexts. Here we review the mechanisms by which EGFR regulates cell metabolism, including by modulation of gene expression and protein function leading to control of glucose uptake, glycolysis, biosynthetic pathways branching from glucose metabolism, amino acid metabolism, lipogenesis, and mitochondrial function. We further examine how this regulation of cell metabolism by EGFR may contribute to cell proliferation and differentiation and how EGFR-driven control of metabolism can impact certain diseases and therapy outcomes.

Targeting apoptosis to manage acquired resistance to third generation EGFR inhibitors

A significant clinical challenge in lung cancer treatment is management of the inevitable acquired resistance to third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs), such as osimertinib, which have shown remarkable success in the treatment of advanced NSCLC with EGFR activating mutations, in order to achieve maximal response duration or treatment remission. Apoptosis is a major type of programmed cell death tightly associated with cancer development and treatment. Evasion of apoptosis is considered a key hallmark of cancer and acquisition of apoptosis resistance is accordingly a key mechanism of drug acquired resistance in cancer therapy. It has been clearly shown that effective induction of apoptosis is a key mechanism for third generation EGFR-TKIs, particularly osimertinib, to exert their therapeutic efficacies and the development of resistance to apoptosis is tightly associated with the emergence of acquired resistance. Hence, restoration of cell sensitivity to undergo apoptosis using various means promises an effective strategy for the management of acquired resistance to third generation EGFR-TKIs.

Therapeutic potential of the novel Bcl-2/Bcl-XL dual inhibitor, APG1252, alone or in combination against non-small cell lung cancer

Targeting the induction of apoptosis is a promising cancer therapeutic strategy with some clinical success. This study focused on evaluating the therapeutic efficacy of the novel Bcl-2/Bcl-X_L dual inhibitor, APG1252-M1 (also named APG-1244; an in vivo active metabolite of APG1252 or pelcitoclax), as a single agent or in combination, against non-small cell lung cancer (NSCLC) cells. APG1252-M1 effectively decreased the survival of some NSCLC cell lines expressing low levels of Mcl-1 and induced apoptosis. Overexpression of ectopic Mcl-1 in the sensitive cells substantially compromised APG1252-M1's cell-killing effects, whereas inhibition of Mcl-1 greatly sensitized insensitive cell lines to APG1252-M1, indicating the critical role of Mcl-1 levels in impacting cell response to APG1252-M1. Moreover, APG1252-M1, when combined with the third generation epidermal growth factor receptor (EGFR) inhibitor, osimertinib, synergistically decreased the survival of EGFR-mutant NSCLC cell lines including those resistant to osimertinib with enhanced induction of apoptosis and abrogated emergence of acquired resistance to osimertinib. Importantly, the combination was effective in inhibiting the growth of osimertinib-resistant tumors in vivo. Collectively, these results demonstrate the efficacy of APG1252 alone or in combination against human NSCLC cells.

Challenges for the application of EGFR-targeting peptide GE11 in tumor diagnosis and treatment

Abnormal regulation of cell signaling pathways on cell survival, proliferation and migration contributes to the development of malignant tumors. Among them, epidermal growth factor receptor (EGFR) is one of the most important biomarkers in many types of malignant solid tumors. Its over-expression and mutation status can be served as a biomarker to identify patients who can be benifit from EGFR tyrosine kinase inhibitors and anti-EGFR monocloncal antibody (mAb) therapy. For decades, researches on EGFR targeted ligands were actively carried out to identify potent candidates for cancer therapy. An ideal EGFR ligand can competitively inhibit the binding of endogenous growth factor, such as epidermal growth factor (EGF) and transforming growth factor-α(TGF-α) to EGFR, thus block EGFR signaling pathway and downregulate EGFR expression. Alternatively, conjugation of EGFR ligands on drug delivery systems (DDS) can facilitate targeting delivery of therapeutics or diagnostic agents to EGFR over-expression tumors via EGFR-mediated endocytosis. GE11 peptide is one of the potent EGFR ligand screened from a phage display peptide library. It is a dodecapeptide that can specifically binds to EGFR with high affinity and selectivity. GE11 has been widely used in the diagnosis and targeted delivery of drugs for radiotherapy, genetherapy and chemotherpy against EGFR positive tumors. In this review, the critical factors affecting the in vivo and in vitro targeting performance of GE11 peptide, including ligand-receptor intermolecular force, linker bond properties and physiochemical properties of carrier materials, are detailedly interpreted. This review provides a valuable vision for the rational design and optimization of GE11-based active targeting strategies for cancer treatment, and it will promote the translation studies of GE11 from lab research to clinical application.

Emerging strategies to overcome resistance to third-generation EGFR inhibitors

Epidermal growth factor receptor (EGFR), the receptor for members of the epidermal growth factor family, regulates cell proliferation and signal transduction; moreover, EGFR is related to the inhibition of tumor cell proliferation, angiogenesis, invasion, metastasis, and apoptosis. Therefore, EGFR has become an important target for the treatment of cancer, including non-small cell lung cancer, head and neck cancer, breast cancer, glioma, cervical cancer, and bladder cancer. First- to third-generation EGFR inhibitors have shown considerable efficacy and have significantly improved disease prognosis. However, most patients develop drug resistance after treatment. The challenge of overcoming intrinsic and acquired resistance in primary and recurrent cancer mediated by EGFR mutations is thus driving the search for alternative strategies in the design of new therapeutic agents. In view of resistance to third-generation inhibitors, understanding the intricate mechanisms of resistance will offer insight for the development of more advanced targeted therapies. In this review, we discuss the molecular mechanisms of resistance to third-generation EGFR inhibitors and review recent strategies for overcoming resistance, new challenges, and future development directions.

Synchronous intracellular delivery of EGFR-targeted antibody-drug conjugates by p38-mediated non-canonical endocytosis

Monoclonal antibodies targeting the epidermal growth factor receptor (EGFR), including cetuximab and panitumumab, have been used in clinic settings to treat cancer. They have also recently been applied to antibody–drug conjugates (ADCs); however, their clinical efficacy is limited by several issues, including lower internalization efficiency. The binding of cetuximab to the extracellular domain of EGFR suppresses ligand-induced events; therefore, we focus on ligand-independent non-canonical EGFR endocytosis for the delivery of ADCs into cells. Tumor necrosis factor-α (TNF-α) strongly induces the endocytosis of the cetuximab-EGFR complex within 15 min via the p38 phosphorylation of EGFR in a tyrosine kinase-independent manner. A secondary antibody conjugated with saporin, a ribosome-inactivating protein, also undergoes internalization with the complex and enhances its anti-proliferative activity. Anti-cancer agents, including cisplatin and temozolomide, also induce the p38-mediated internalization. The results of the present study demonstrate that synchronous non-canonical EGFR endocytosis may be a feasible strategy for promoting the therapeutic efficacy of EGFR-targeting ADCs in clinical settings.

An integral genomic signature approach for tailored cancer therapy using genome-wide sequencing data

Low-cost multi-omics sequencing is expected to become clinical routine and transform precision oncology. Viable computational methods that can facilitate tailored intervention while tolerating sequencing biases are in high demand. Here we propose a class of transparent and interpretable computational methods called integral genomic signature (iGenSig) analyses, that address the challenges of cross-dataset modeling through leveraging information redundancies within high-dimensional genomic features, averaging feature weights to prevent overweighing, and extracting unbiased genomic information from large tumor cohorts. Using genomic dataset of chemical perturbations, we develop a battery of iGenSig models for predicting cancer drug responses, and validate the models using independent cell-line and clinical datasets. The iGenSig models for five drugs demonstrate predictive values in six clinical studies, among which the Erlotinib and 5-FU models significantly predict therapeutic responses in three studies, offering clinically relevant insights into their inverse predictive signature pathways. Together, iGenSig provides a computational framework to facilitate tailored cancer therapy based on multi-omics data.

Afatinib, an effective treatment for patient with lung squamous cell carcinoma harboring uncommon EGFR G719A and R776C co-mutations

BACKGROUND

Epidermal growth factor receptor (EGFR) is a crucial driven gene in non-small cell lung cancer (NSCLC), and the EGFR mutation rate in lung squamous cell carcinoma (SCC) is only 3 ~ 6.92%. Uncommon EGFR mutations, such as S768I, L861Q and G719X, accounting for approximately 15% of NSCLC harboring EGFR mutation. Afatinib, a second-generation EGFR-tyrosine kinase inhibitor (TKI), has been approved for NSCLC harboring uncommon mutations by the FDA in 2018. In our report, the lung SCC patient harboring uncommon compound EGFR mutation (G719A and R776C) benefited from afatinib.

CASE PRESENTATION

A case of a lung SCC patient harboring uncommon compound EGFR mutation (G719A and R776C) benefited from afatinib, and new MYC amplification was detected by next-generation sequencing (NGS) after disease progression.

CONCLUSIONS

This case first identified a patient with lung squamous cell carcinoma harboring uncommon compound EGFR mutation (G719A and R776C) benefited from afatinib and achieved 11 months of progression-free survival (PFS). Then, new MYC amplification was detected after disease progression, indicating that MYC amplification may be one of the reasons for afatinib resistance.

Epigenome-wide three-way interaction study identifies a complex pattern between TRIM27, KIAA0226, and smoking associated with overall survival of early-stage NSCLC

The interaction between DNA methylation of tripartite motif containing 27 (cg05293407_TRIM27 ) and smoking has previously been identified to reveal histologically heterogeneous effects of TRIM27 DNA methylation on early-stage non-small-cell lung cancer (NSCLC) survival. However, to understand the complex mechanisms underlying NSCLC progression, we searched three-way interactions. A two-phase study was adopted to identify three-way interactions in the form of pack-year of smoking (number of cigarettes smoked per day × number of years smoked) × cg05293407_TRIM27  × epigenome-wide DNA methylation CpG probe. Two CpG probes were identified with FDR-q ≤ 0.05 in the discovery phase and P ≤ 0.05 in the validation phase: cg00060500_KIAA0226 and cg17479956_EXT2 . Compared to a prediction model with only clinical information, the model added 42 significant three-way interactions using a looser criterion (discovery: FDR-q ≤ 0.10, validation: P ≤ 0.05) had substantially improved the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model for both 3-year and 5-year survival. Our research identified the complex interaction effects among multiple environment and epigenetic factors, and provided therapeutic target for NSCLC patients.