Intrinsic resistance to EGFR tyrosine kinase inhibitors in advanced non-small-cell lung cancer with activating EGFR mutations

STAT3 Pathways Contribute to β-HCH Interference with Anticancer Tyrosine Kinase Inhibitors

Organochlorine pesticides (OCPs) are a class of environmentally persistent and bioaccumulative pollutants. Among these, β-hexachlorocyclohexane (β-HCH) is a byproduct of lindane synthesis, one of the most worldwide widespread pesticides. β-HCH cellular mechanisms inducing chemical carcinogenesis correspond to many of those inducing chemoresistance, in particular, by the activation of signal transducer and activator of transcription 3 (STAT3) signaling pathways. For this purpose, four cell lines, representative of breast, lung, prostate, and hepatocellular cancers, were treated with β-HCH, specific tyrosine kinase inhibitors (TKIs), and a STAT3 inhibitor. All cell samples were analyzed by a viability assay, immunoblotting analysis, a wound-healing assay, and a colony formation assay. The results show that β-HCH reduces the efficacy of TKIs. The STAT3 protein, in this context, plays a central role. In fact, by inhibiting its activity, the efficacy of the anticancer drug is restored. Furthermore, this manuscript aimed to draw the attention of the scientific and socio-healthcare community to the issue of prolonged exposure to contaminants and their impact on drug efficacy.

Influence of TP53 mutation on efficacy and survival in advanced EGFR-mutant non-small cell lung cancer patients treated with third-generation EGFR tyrosine kinase inhibitors

TP53 comutation is related to poor prognosis of non-small cell lung cancer. However, there is limited study focusing on the structural influence of TP53 mutation on third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment. We retrospectively analyzed the clinical and molecular data of patients treated with third-generation EGFR-TKIs in two independent cohorts. A total of 117 patients from the Sun Yat-sen University Cancer Center (SYSUCC) and 141 patients from the American Association for Cancer Research Project GENIE database were included. In the SYSUCC cohort, TP53 comutations were found in 59 patients (50.4%) and were associated with poor median progress-free survival (mPFS) and median overall survival (mOS). The additional subtype analysis found that TP53 mutation in the alpha-helix region had shorter mOS compared with those with TP53 mutations in other regions in the SYSUCC cohort (mOS, 12.2 vs. 21.7 months; p = 0.027). Similar findings were confirmed in the GENIE cohort. Specifically, the presence of TP53 mutation in the alpha-helix region was an independent negative predictive factor for PFS [hazard ratio (HR) 2.05(1.01-4.18), p = 0.048] and OS [HR 3.62(1.60-8.17), p = 0.002] in the SYSUCC cohort. TP53 mutation in alpha-helix region was related to inferior clinical outcomes in patients treated with third-generation EGFR-TKIs.

The study of primary and acquired resistance to first-line osimertinib to improve the outcome of EGFR-mutated advanced Non-small cell lung cancer patients: the challenge is open for new therapeutic strategies

The development of targeted therapy in epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) patients has radically changed their clinical perspectives. Current first-line standard treatment for advanced disease is commonly considered third-generation tyrosine kinase inhibitors (TKI), osimertinib. The study of primary and acquired resistance to front-line osimertinib is one of the main burning issues to further improve patients' outcome. Great heterogeneity has been depicted in terms of duration of clinical benefit and pattern of progression and this might be related to molecular factors including subtypes of EGFR mutations and concomitant genetic alterations. Acquired resistance can be categorized into two main classes: EGFR-dependent and EGFR-independent mechanisms and specific pattern of progression to first-line osimertinib have been demonstrated. The purpose of the manuscript is to provide a comprehensive overview of literature about molecular resistance mechanisms to first-line osimertinib, from a clinical perspective and therefore in relationship to emerging therapeutic approaches.

Molecular mechanisms underlying the regulation of tumour suppressor genes in lung cancer

Tumour suppressor genes play a cardinal role in the development of a large array of human cancers, including lung cancer, which is one of the most frequently diagnosed cancers worldwide. Therefore, extensive studies have been committed to deciphering the underlying mechanisms of alterations of tumour suppressor genes in governing tumourigenesis, as well as resistance to cancer therapies. In spite of the encouraging clinical outcomes demonstrated by lung cancer patients on initial treatment, the subsequent unresponsiveness to first-line treatments manifested by virtually all the patients is inherently a contentious issue. In light of the aforementioned concerns, this review compiles the current knowledge on the molecular mechanisms of some of the tumour suppressor genes implicated in lung cancer that are either frequently mutated and/or are located on the chromosomal arms having high LOH rates (1p, 3p, 9p, 10q, 13q, and 17p). Our study identifies specific genomic loci prone to LOH, revealing a recurrent pattern in lung cancer cases. These loci, including 3p14.2 (FHIT), 9p21.3 (p16INK4a), 10q23 (PTEN), 17p13 (TP53), exhibit a higher susceptibility to LOH due to environmental factors such as exposure to DNA-damaging agents (carcinogens in cigarette smoke) and genetic factors such as chromosomal instability, genetic mutations, DNA replication errors, and genetic predisposition. Furthermore, this review summarizes the current treatment landscape and advancements for lung cancers, including the challenges and endeavours to overcome it. This review envisages inspired researchers to embark on a journey of discovery to add to the list of what was known in hopes of prompting the development of effective therapeutic strategies for lung cancer.

Leucine Zipper Downregulated in Cancer-1 Interacts with Clathrin Adaptors to Control Epidermal Growth Factor Receptor (EGFR) Internalization and Gefitinib Response in EGFR-Mutated Non-Small Cell Lung Cancer

The epidermal growth factor receptor (EGFR) is a common driver of non-small cell lung cancer (NSCLC). Clathrin-mediated internalization (CMI) sustains EGFR signaling. AXL is associated with resistance to EGFR-tyrosine kinase inhibitors (TKIs) in EGFR-mutated (EGFRM) NSCLC. We investigated the effects of Leucine zipper downregulated in cancer-1 (LDOC1) on EGFR CMI and NSCLC treatment. Coimmunoprecipitation, double immunofluorescence staining, confocal microscopy analysis, cell surface labelling assays, and immunohistochemistry studies were conducted. We revealed that LDOC1 interacts with clathrin adaptors through binding motifs. LDOC1 depletion promotes internalization and plasma membrane recycling of EGFR in EGFRM NSCLC PC9 and HCC827 cells. Membranous and cytoplasmic EGFR decreased and increased, respectively, in LDOC1 (-) NSCLC tumors. LDOC1 depletion enhanced and sustained activation of EGFR, AXL, and HER2 and enhanced activation of HER3 in PC9 and HCC827 cells. Sensitivity to first-generation EGFR-TKIs (gefitinib and erlotinib) was significantly reduced in LDOC1-depleted PC9 and HCC827 cells. Moreover, LDOC1 downregulation was significantly associated (p < 0.001) with poor overall survival in patients with EGFRM NSCLC receiving gefitinib (n = 100). In conclusion, LDOC1 may regulate the efficacy of first-generation EGFR-TKIs by participating in the CMI of EGFR. Accordingly, LDOC1 may function as a prognostic biomarker for EGFRM NSCLC.

A perspective on emerging therapies in metastatic colorectal cancer: Focusing on molecular medicine and drug resistance

The majority of cancer cases are colorectal cancer, which is also the second largest cause of cancer-related deaths worldwide. Metastasis is the leading cause of death for patients with colorectal cancer. Metastatic colorectal cancer incidence are on the rise due to a tiny percentage of tumors developing resistant to medicines despite advances in treatment tactics. Cutting-edge targeted medications are now the go-to option for customized and all-encompassing CRC care. Specifically, multitarget kinase inhibitors, antivascular endothelial growth factors, and epidermal growth factor receptors are widely used in clinical practice for CRC-targeted treatments. Rare targets in metastatic colorectal cancer are becoming more well-known due to developments in precision diagnostics and the extensive use of second-generation sequencing technology. These targets include the KRAS mutation, the BRAF V600E mutation, the HER2 overexpression/amplification, and the MSI-H/dMMR. Incorporating certain medications into clinical trials has significantly increased patient survival rates, opening new avenues and bringing fresh viewpoints for treating metastatic colorectal cancer. These focused therapies change how cancer is treated, giving patients new hope and better results. These markers can significantly transform and individualize therapy regimens. They could open the door to precisely customized and more effective medicines, improving patient outcomes and quality of life. The fast-growing body of knowledge regarding the molecular biology of colorectal cancer and the latest developments in gene sequencing and molecular diagnostics are directly responsible for this advancement.

Ganoderma microsporum immunomodulatory protein as an extracellular epidermal growth factor receptor (EGFR) degrader for suppressing EGFR-positive lung cancer cells

Epidermal growth factor receptor (EGFR) abnormalities relevant to tumor progression. A newly developed strategy for cancer therapy is induction of EGFR degradation. GMI, an immunomodulatory protein from the medicinal mushroom Ganoderma microsporum, exhibits anticancer activity. However, its role in the intracellular trafficking and degradation of EGFR remains unclear. In this study, we discovered that GMI inhibits the phosphorylation of multiple tyrosine kinases. Specifically, GMI was discovered to suppress lung cancer cells harboring both wild-type and mutant EGFR by inhibiting EGFR dimerization and eliminating EGFR-mediated signaling. Functional studies revealed that GMI binds to the extracellular segment of EGFR. GMI interacts with EGFR to induce phosphorylation of EGFR at tyrosine1045, which triggers clathrin-dependent endocytosis and degradation of EGFR. Furthermore, in the mouse models, GMI was discovered to suppress tumor growth. Knockdown of EGFR in lung cancer cells abolishes GMI's anticancer activity in vivo and in vitro. Our results reveal the interaction mechanisms through which GMI induces EGFR degradation and abolishes EGFR-mediated intracellular pathway. Our study indicates that GMI is an EGFR degrader for inhibiting EGFR-expressing tumor growth.

PDL1-status predicts primary resistance of metastatic, EGFR-mutated non small cell lung cancers to EGFR tyrosine-kinase inhibitors

BACKGROUND

EGFR tyrosine-kinase inhibitors (TKIs) are the reference treatment for metastatic, EGFR-mutated, non-small-cell lung cancers (EGFRm NSCLCs). However, 16-20% of those tumors progress early (3-6 months) and factors predicting that resistance are unknown. This study was undertaken to examine PDL1 status as such a factor.

METHODS

This retrospective analysis included metastatic, EGFRm-NSCLC patients who received first-line 1st-, 2nd- or 3rd-generation EGFR TKIs with PDL1 expression determined in pretreatment biopsies. Kaplan-Meier estimations of probabilities of progression-free survival (PFS) and overall survival (OS) were compared with log-rank test, and logistic-regression analyses.

RESULTS

PDL1 status of the 145 included patients was ≥1% (47%), 1-49% (33%) or ≥50% (14%). For PDL1-positive vs PDL1-negative patients, respectively, median PFS lasted 8 (95% CI: 6-12) vs 12 (95% CI: 11-17) months (p = 0.008), with 18% vs. 8% (NS) of NSCLCs progressing at 3 months, and 47% vs. 18% (HR 0.25 [95% CI 0.10-0.566], p<0.001) at 6 months. Multivariate analysis retained 1st- or 2nd-generation EGFR TKI, brain metastases and albuminemia <35 g/L at diagnosis as significantly associated with shorter PFS, but not PDL1 status, which was independently associated with progression at 6 months (HR 3.76 [1.23-12.63], p = 0.02). PDL1-negative and PDL1-positive patients' OS lasted 27 (95% CI 24-39) and 22 (95% CI 19-41) months, respectively (NS). Multivariate analysis retained only brain metastases or albuminemia <35 g/L at diagnosis as being independently associated with OS.

CONCLUSION

PDL1 expression ≥1% seems to be associated with early progression during the first 6 months of first-line EGFR-TKI treatment of metastatic EGFRm NSCLCs, without impacting OS.

Targeting Epidermal Growth Factor Receptor for Cancer Treatment: Abolishing Both Kinase-Dependent and Kinase-Independent Functions of the Receptor

Epidermal growth factor receptor (EGFR), a receptor tyrosine kinase, is activated by ligand binding, overexpression, or mutation. It is well known for its tyrosine kinase-dependent oncogenic activities in a variety of human cancers. A large number of EGFR inhibitors have been developed for cancer treatment, including monoclonal antibodies, tyrosine kinase inhibitors, and a vaccine. The EGFR inhibitors are aimed at inhibiting the activation or the activity of EGFR tyrosine kinase. However, these agents have shown efficacy in only a few types of cancers. Drug resistance, both intrinsic and acquired, is common even in cancers where the inhibitors have shown efficacy. The drug resistance mechanism is complex and not fully known. The key vulnerability of cancer cells that are resistant to EGFR inhibitors has not been identified. Nevertheless, it has been increasingly recognized in recent years that EGFR also possesses kinase-independent oncogenic functions and that these noncanonical functions may play a crucial role in cancer resistance to EGFR inhibitors. In this review, both kinase-dependent and -independent activities of EGFR are discussed. Also discussed are the mechanisms of actions and therapeutic activities of clinically used EGFR inhibitors and sustained EGFR overexpression and EGFR interaction with other receptor tyrosine kinases to counter the EGFR inhibitors. Moreover, this review discusses emerging experimental therapeutics that have shown potential for overcoming the limitation of the current EGFR inhibitors in preclinical studies. The findings underscore the importance and feasibility of targeting both kinase-dependent and -independent functions of EGFR to enhance therapeutic efficacy and minimize drug resistance. SIGNIFICANCE STATEMENT: EGFR is a major oncogenic driver and therapeutic target, but cancer resistance to current EGFR inhibitors remains a significant unmet clinical problem. This article reviews the cancer biology of EGFR as well as the mechanisms of actions and the therapeutic efficacies of current and emerging EGFR inhibitors. The findings could potentially lead to development of more effective treatments for EGFR-positive cancers.

Impact of RBM10 and PD-L1 expression on the prognosis of pathologic N1-N2 epidermal growth factor receptor mutant lung adenocarcinoma

Background

Impact of RNA-binding motif protein 10 (RBM10) and programmed death-ligand 1 (PD-L1) on the postoperative prognosis of patients with epidermal growth factor receptor gene mutation (EGFR-Mt) lung adenocarcinoma with pathological lymph node metastasis is still unclear.

Methods

Patients who underwent curative surgery for pN1-N2 EGFR-Mt lung adenocarcinoma (n=129) harboring the EGFR exon 19 deletion mutation (Ex19) (n=66) or EGFR exon 21 L858R mutation (Ex21) (n=63) between January 2010 and December 2020 were included in this retrospective study. The prognoses of patients with low/high cytoplasmic RBM10 expression and PD-L1 negativity/positivity based on immunohistochemistry (IHC) of resected specimens were compared using the log-rank test. The effects of RBM10 and PD-L1 expression on overall survival (OS) were examined via multivariable analysis using the Cox proportional hazards regression model. The effects of RBM10 and PD-L1 expression on progression-free survival (PFS) of EGFR-tyrosine kinase inhibitors (TKIs) therapy among patients with recurrent pN1-N2 EGFR-Mt lung adenocarcinoma (n=67) were examined using log-rank tests.

Results

The RBM10 low expression group showed significantly better 5-year OS than the RBM10 high expression group (89.4% vs. 71.5%, P=0.020), and the PD-L1 negative group tended to have longer 5-year OS than the PD-L1 positive group (86.4% vs. 68.4%, P=0.050). Multivariable analysis showed that high RBM10 expression [hazard ratio (HR), 3.12; 95% confidence interval (CI): 1.19-8.17; P=0.021] and PD-L1 positivity (HR, 3.80; 95% CI: 1.64-8.84; P=0.002) were independent poor prognostic factors for OS. PFS of patients with relapse and first-line EGFR-TKI treatment was significantly better in the PD-L1-negative group than in the PD-L1-positive group (34.5 vs. 12.1 months, P=0.045). PFS of patients with Ex21 relapse and first-line EGFR-TKI treatment was significantly better in the RBM10 low expression group than in the RBM10 high expression group (25.5 vs. 13.0 months, P=0.025).

Conclusions

High RBM10 expression and PD-L1 positivity are poor prognostic factors for OS in patients with pN1-N2 EGFR-Mt lung adenocarcinoma after curative surgery. In patients with recurrent pN1-N2 EGFR-Mt lung adenocarcinoma, PD-L1 and RBM10 expression may influence response to EGFR-TKIs.

Regulation of Ferroptosis in Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) is the most common lung cancer, which accounts for about 35-40% of all lung cancer patients. Despite therapeutic advancements in recent years, the overall survival time of LUAD patients still remains poor, especially KRAS mutant LUAD. Therefore, it is necessary to further explore novel targets and drugs to improve the prognos is for LUAD. Ferroptosis, an iron-dependent regulated cell death (RCD) caused by lipid peroxidation, has attracted much attention recently as an alternative target for apoptosis in LUAD therapy. Ferroptosis has been found to be closely related to LUAD at every stage, including initiation, proliferation, and progression. In this review, we will provide a comprehensive overview of ferroptosis mechanisms, its regulation in LUAD, and the application of targeting ferroptosis for LUAD therapy.

Aberrant m5C hypermethylation mediates intrinsic resistance to gefitinib through NSUN2/YBX1/QSOX1 axis in EGFR-mutant non-small-cell lung cancer

BACKGROUND

RNA 5-methylcytosine (m⁵C) modification plays critical roles in the pathogenesis of various tumors. However, the function and molecular mechanism of RNA m⁵C modification in tumor drug resistance remain unclear.

METHODS

The correlation between RNA m⁵C methylation, m⁵C writer NOP2/Sun RNA methyltransferase family member 2 (NSUN2) and EGFR-TKIs resistance was determined in non-small-cell lung cancer (NSCLC) cell lines and patient samples. The effects of NSUN2 on EGFR-TKIs resistance were investigated by gain- and loss-of-function assays in vitro and in vivo. RNA-sequencing (RNA-seq), RNA bisulfite sequencing (RNA-BisSeq) and m⁵C methylated RNA immunoprecipitation-qPCR (MeRIP-qPCR) were performed to identify the target gene of NSUN2 involved in EGFR-TKIs resistance. Furthermore, the regulatory mechanism of NSUN2 modulating the target gene expression was investigated by functional rescue and puromycin incorporation assays.

RESULTS

RNA m⁵C hypermethylation and NSUN2 were significantly correlated with intrinsic resistance to EGFR-TKIs. Overexpression of NSUN2 resulted in gefitinib resistance and tumor recurrence, while genetic inhibition of NSUN2 led to tumor regression and overcame intrinsic resistance to gefitinib in vitro and in vivo. Integrated RNA-seq and m⁵C-BisSeq analyses identified quiescin sulfhydryl oxidase 1 (QSOX1) as a potential target of aberrant m⁵C modification. NSUN2 methylated QSOX1 coding sequence region, leading to enhanced QSOX1 translation through m⁵C reader Y-box binding protein 1 (YBX1).

CONCLUSIONS

Our study reveals a critical function of aberrant RNA m⁵C modification via the NSUN2-YBX1-QSOX1 axis in mediating intrinsic resistance to gefitinib in EGFR-mutant NSCLC.

Genomic Landscape of Primary Resistance to Osimertinib Among Hispanic Patients with EGFR-Mutant Non-Small Cell Lung Cancer (NSCLC): Results of an Observational Longitudinal Cohort Study

BACKGROUND

Epidermal growth factor receptor (EGFR) mutations (EGFRm) represent one of the most common genomic alterations identified among patients with non-small cell lung cancer (NSCLC). Several targeted agents for patients with EGFRm have been proven safe and effective, including the third-generation tyrosine kinase inhibitor (TKI) osimertinib. Nonetheless, some patients will present with or develop EGFR-TKI resistance mechanisms.

OBJECTIVE

We characterized the genomic landscape of primary resistance to osimertinib among Hispanic patients with EGFR-mutant NSCLC.

METHODS

An observational longitudinal cohort study was conducted with two groups of patients, those with intrinsic resistance (cohort A) and those with long-term survival (cohort B). All patients were treated and followed between January 2018 and May 2022. All patients were assessed for Programmed Cell Death Ligand 1 (PD-L1) expression and Bcl-2-like protein 11 (BIM)/AXL mRNA expression before starting TKI. After 8 weeks of treatment, a liquid biopsy was performed to determine the presence of circulating free DNA (cfDNA), and next-generation sequencing (NGS) was used to identify mutations at the time of progression. In both cohorts, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) were evaluated.

RESULTS

We found a homogeneous distribution of EGFR-sensitizing mutations in both cohorts. For cohort A, exon 21 mutations were more common than exon 19 deletions (ex19dels) for cohort B (P = 0.0001). The reported ORR for osimertinib was 6.3% and 100% for cohorts A and B, respectively (P = 0.0001). PFS was significantly higher in cohort B (27.4 months vs. 3.1 months; P = 0.0001) and ex19del patients versus L858R (24.5 months, 95% confidence interval [CI] 18.2-NR), vs. 7.6 months, 95% CI 4.8-21.1; P = 0.001). OS was considerably lower for cohort A (20.1 months vs. 36.0 months; P = 0.0001) and was better for patients with ex19del, no brain metastasis, and low tumor mutation burden. At the time of progression, more mutations were found in cohort A, identifying off-target alterations more frequently, including TP53, RAS, and RB1.

CONCLUSION

EGFR-independent alterations are common among patients with primary resistance to osimertinib and significantly impact PFS and OS. Our results suggest that among Hispanic patients, other variables associated with intrinsic resistance include the number of commutations, high levels AXL mRNA, and low levels of BIM mRNA, T790M de novo, EGFR p.L858R presence, and a high tumoral mutational burden.

Prognostic value of sarcopenia in patients with lung cancer treated with epidermal growth factor receptor tyrosine kinase inhibitors or immune checkpoint inhibitors

Objectives

It remains controversial whether sarcopenia has any significant impact on the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) or immune checkpoint inhibitors (ICIs) in patients with advanced non-small cell lung cancer (NSCLC). Therefore, in this study, we aimed to assess the association between sarcopenia and clinical outcomes in patients with advanced NSCLC receiving EGFR-TKIs or ICIs as a first-line therapy.

Methods

We retrospectively enrolled 131 patients with advanced NSCLC treated with first-line EGFR-TKIs or ICIs between 1 March 2019 and 31 March 2021. To estimate sarcopenia, we calculated skeletal muscle index (SMI) as the ratio of skeletal muscle area (cm2) to height squared (m2). Associations between sarcopenia and overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan–Meier method and log-rank tests, respectively. A Cox proportional hazards regression model was used to assess the factors associated with OS and PFS. The Student’s t-test or Mann–Whitney U test was used to compare the SMI between patients with or without objective response and disease control. The chi-squared test was used to compare adverse events (AEs) between patients with and without sarcopenia.

Results

Among the 131 patients, 35 (26.7%) were diagnosed with sarcopenia. Sarcopenia was an independent predictor of poor OS and PFS (p &lt; 0.05) overall and in the EGFR-TKI- and ICI-treated cohorts. Among all patients, those with sarcopenia showed significantly shorter OS and PFS than those without sarcopenia (median OS and PFS: 13.0 vs. 26.0 months and 6.4 vs. 15.1 months; both p &lt; 0.001). These associations were consistent across the subtypes of most clinical characteristics. Statistically significant differences between the objective response (OR) and non-OR groups were also observed in the mean SMI (OR group, 43.89 ± 7.55 vs. non-OR group, 38.84 ± 7.11 cm2/m2; p &lt; 0.001). In addition, we observed similar results with disease control (DC) and non-DC groups (DC group, 42.46 ± 7.64 vs. non-DCR group, 33.74 ± 4.31 cm2/m2; p &lt; 0.001). The AEs did not differ significantly between the sarcopenia and non-sarcopenia groups.

Conclusion

Sarcopenia before treatment might be a significant predictor of poor clinical outcomes (shorter OS and PFS, fewer ORs, less DC) in patients with advanced NSCLC treated with EGFR-TKIs or ICIs as the first-line therapy.

Nanotechnology-based approaches overcome lung cancer drug resistance through diagnosis and treatment

Lung cancer continues to be a malignant tumor with high mortality. Two obstacles interfere with curative therapy of lung cancer: (i) poor diagnosis at the early stages, as symptoms are not specific or asymptomatic; and (ii) invariably emerging drug resistance after treatment. Some factors contributing to drug resistance include preexisting genetic/genomic drug-resistant alteration(s); activation of adaptive drug resistance pathways; remodeling of the tumor microenvironment; and pharmacological mechanisms or activation of drug efflux pumps. Despite the mechanisms explored to better understand drug resistance, a gap remains between molecular understanding and clinical application. Therefore, facilitating the translation of basic science into the clinical setting is a great challenge. Nanomedicine has emerged as a promising tool for cancer treatment. Because of their excellent physicochemical properties and enhanced permeability and retention effects, nanoparticles have great potential to revolutionize conventional lung cancer diagnosis and combat drug resistance. Nanoplatforms can be designed as carriers to improve treatment efficacy and deliver multiple drugs in one system, facilitating combination treatment to overcome drug resistance. In this review, we describe the difficulties in lung cancer treatment and review recent research progress on nanoplatforms aimed at early diagnosis and lung cancer treatment. Finally, future perspectives and challenges of nanomedicine are also discussed.

Monitoring EGFR-lung cancer evolution: a possible beginning of a "methylation era" in TKI resistance prediction

The advances in scientific knowledge on biological therapies of the last two decades have impressively oriented the clinical management of non-small-cell lung cancer (NSCLC) patients. The treatment with tyrosine kinase inhibitors (TKIs) in patients harboring Epidermal Growth Factor Receptor (EGFR)-activating mutations is dramatically associated with an improvement in disease control. Anyhow, the prognosis for this selected group of patients remains unfavorable, due to the innate and/or acquired resistance to biological therapies. The methylome analysis of many tumors revealed multiple patterns of methylation at single/multiple cytosine-phosphate-guanine (CpG) sites that are linked to the modulation of several cellular pathways involved in cancer onset and progression. In lung cancer patients, ever increasing evidences also suggest that the association between DNA methylation changes at promoter/intergenic regions and the consequent alteration of gene-expression signatures could be related to the acquisition of resistance to biological therapies. Despite this intriguing hypothesis, large confirmatory studies are demanded to consolidate and finalize many preliminary observations made in this field. In this review, we will summarize the available knowledge about the dynamic role of DNA methylation in EGFR-mutated NSCLC patients.

Efficacy and safety of Kanglaite plus EGFR-TKI in the treatment of advanced non-small cell lung cancer: A meta-analysis of 13 RCTs

BACKGROUND

Kanglaite (KLT) is a Chinese medicine antitumor drug independently developed in China, which has been widely used in the treatment of advanced non-small cell lung cancer (NSCLC). The purpose of this study was to systematically evaluate the efficacy and safety of KLT plus epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) in the treatment of advanced NSCLC.

METHODS

Up to September 1, 2022, the databases of PubMed, EMBASE, Cochrane Library, ClinicalTrials.gov, China National Knowledge Infrastructure, Chinese Biomedical Literature, China Science and Technology Journal, and Wanfang were searched, and the randomized controlled clinical trials (RCTs) of KLT plus EGFR-TKI in the treatment of advanced NSCLC were included. Two researchers independently screened the literature, extracted data, and evaluated the quality of the included literature. Revman5.4 software was used for meta-analysis.

RESULTS

A total of 1057 patients were included in 13 RCTs. The results of meta-analysis showed that KLT plus EGFR-TKI could improve the objective response rate (ORR) (risk ratio (RR) confidence interval (CI) [RR = 1.54, 95% CI: 1.27-1.86, P < .00001]), the disease control rate (DCR) (RR = 1.23, 95% CI: 1.14-1.32, P < .00001), and quality of life (QOL) (RR = 1.79, 95% CI: 1.36-2.36, P < .0001) in patients with advanced NSCLC. The percentages of CD3+T cells (standardized mean difference [SMD = 2.37, 95% CI: 0.80-3.93, P = .003]), CD4+T cells (SMD = 1.39, 95% CI: 0.85-1.93, P < .00001), NK cells (SMD = 1.59, 95% CI: 0.88-2.30, P < .0001), and CD4+/CD8+ratio (SMD = 0.37, 95% CI: 0.19-0.55, P < .0001) were also increased. However, the results of subgroup analysis showed that in patients with EGFR mutation NSCLC, compared with EGFR-TKI alone, KLT plus EGFR-TKI did not significantly increase ORR and DCR (RR = 1.43, 95% CI: 0.88-2.32, P = .15; RR = 1.07, 95% CI: 0.96-1.20, P = .21). In terms of adverse events of drugs, the incidence of diarrhea, rash, anorexia, nausea and vomiting, liver and renal function damage of KLT plus EGFR-TKI was similar to that of EGFR-TKI alone (P > .05).

CONCLUSION

KLT plus EGFR-TKI has some clinical benefits and good safety compared with EGFR-TKI alone in the treatment of advanced NSCLC. However, it seems that patients with EGFR mutations do not get significant clinical benefits, and more high-quality RCTs are needed to prove the efficacy of the combined regimen.

Development and validation of a new LC–MS/MS method for the determination of mefatinib in human plasma and its first application in pharmacokinetic studies

Mefatinib (MET306) is a novel second-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) designed to address the highly unmet clinical need of gefitinib-induced resistance and irreversibly bind to mutated tyrosine kinase domain of EGFR and human epidermal growth factor receptor 2 (HER2). In this study, a liquid chromatography–tandem mass spectrometry method was established and validated for determining MET306 in non-small cell lung cancer patients and a backpropagation artificial neural network was developed and constructed to predict the pharmacokinetic process. The mobile phase was water containing 5 mM ammonium acetate and acetonitrile at a flow rate of 0.3 mL min−1, within a 4.5 min run time. MET306 was separated on a Hypersil Gold-C18 at 40 °C and subjected to mass analysis using positive electrospray ionization. A total of 524 data were used as development groups and 145 data were used as testing groups. The final established Northern Goshawk Optimization-Backpropagation Artificial Neural Network (NGO-BPANN) model consisted of one input layer with 6 neurons, 1 hidden layer with 10 nodes, and 1 output layer with one node processed by MATLAB2021a.The calibration range of MET306 was 0.5–200 ng mL−1 with the correlation coefficient r ≥ 0.99. Accuracies ranged from 97.20 to 110.80% and the inter- and intra-assay precision were less than 15%. The ranges of extraction recoveries were 104.95% to 112.09% for analyte and internal standard and there was no significant matrix effect. The storage stability under different conditions was in accordance with the bioanalytical guidelines. The time-concentration profiles of the measured and predicted concentrations of MET306 by NGO-BPANN agree well. An NGO-BPANN model was developed to predict the plasma concentration and pharmacokinetic parameters of MET306 in the first time.

Emerging genetic biomarkers in lung adenocarcinoma

Comprehensive genomic profiling is a next-generation sequencing approach used to detect several known and emerging genomic alterations. Many genomic variants detected by comprehensive genomic profiling have become recognized as significant cancer biomarkers, leading to the development of major clinical trials. Lung adenocarcinoma has become one of the most targeted cancers for genomic profiling with a series of actionable mutations such as EGFR, KRAS, HER2, BRAF, FGFR, MET, ALK, and many others. The importance of these mutations lies in establishing targeted therapies that significantly change the outcome in lung adenocarcinoma besides the prognostic value of some mutations. This review sheds light on the development of the comprehensive genomic profiling field, mainly lung adenocarcinoma, and discusses the role of a group of mutations in this disease.

Identification of EGFR-Related LINC00460/mir-338-3p/MCM4 Regulatory Axis as Diagnostic and Prognostic Biomarker of Lung Adenocarcinoma Based on Comprehensive Bioinformatics Analysis and Experimental Validation

Background: Lung adenocarcinoma (LUAD) is one of the most aggressive and lethal tumor types and requires effective diagnostic and therapeutic targets. Though the epidermal growth factor receptor (EGFR) is an important target for LUAD therapy, acquired resistance is still inevitable. In recent years, the regulation of the EGFR by competing endogenous RNAs (ceRNAs) has been extensively studied and significant progress has been made. Therefore, we aim to find new targets for the diagnosis and treatment of LUAD by analyzing the EGFR-related ceRNA network in LUAD and expect to address the problem of EGFR resistance. Methods: We identified differentially expressed lncRNAs, miRNAs and mRNAs closely associated with the EGFR by analyzing transcriptome data from LUAD samples. Comprehensive bioinformatics analysis strongly suggests that the LINC00460-mir-338-3p-MCM4 ceRNA network plays an important role in the diagnosis and prognosis of LUAD. The effects of different patterns of the LINC00460/MCM4 axis on the overall survival of patients with LUAD were analyzed by a polygene regulation model. We also verified the expression of these genes in LUAD cell lines and tumor tissues by RT-PCR and immunohistochemistry. The functional enrichment analysis and targeted drug prediction of the MCM4 gene were performed. Results: Survival analysis indicated that high expressions of LINC00460 and MCM4 predict a shorter survival period for patients. Univariate and multivariate regression analyses demonstrated that higher expressions of LINC00460 and MCM4 were significantly associated with tumor size, lymph node metastasis, distant metastasis and TNM stage. A multi-gene regulation model analysis revealed that the LINC00460 (downregulation)-mir-338-3p (upregulation)-MCM4 (downregulation) pattern significantly improved the overall survival of LUAD patients (p = 0.0093). RT-PCR and immunohistochemical experiments confirmed our analytical results. In addition, the functional enrichment analysis indicated that MCM4-related genes were mainly enriched in the cell cycle and cell division. A functional association network analysis showed that MCM4 was closely related to the EGFR. Finally, the possible targeted drugs of MCM4 were queried through the drug database platform, hoping to solve its drug resistance problem by targeting EGFR-related genes. Conclusions: In summary, the LINC00460/MCM4 axis can be used as a potential new perspective for targeting EGFR genes in precision medicine and is expected to serve as a diagnostic, prognostic and drug target for LUAD.

Targeting Ferroptosis Pathway to Combat Therapy Resistance and Metastasis of Cancer

Ferroptosis is an iron-dependent regulated form of cell death caused by excessive lipid peroxidation. This form of cell death differed from known forms of cell death in morphological and biochemical features such as apoptosis, necrosis, and autophagy. Cancer cells require higher levels of iron to survive, which makes them highly susceptible to ferroptosis. Therefore, it was found to be closely related to the progression, treatment response, and metastasis of various cancer types. Numerous studies have found that the ferroptosis pathway is closely related to drug resistance and metastasis of cancer. Some cancer cells reduce their susceptibility to ferroptosis by downregulating the ferroptosis pathway, resulting in resistance to anticancer therapy. Induction of ferroptosis restores the sensitivity of drug-resistant cancer cells to standard treatments. Cancer cells that are resistant to conventional therapies or have a high propensity to metastasize might be particularly susceptible to ferroptosis. Some biological processes and cellular components, such as epithelial–mesenchymal transition (EMT) and noncoding RNAs, can influence cancer metastasis by regulating ferroptosis. Therefore, targeting ferroptosis may help suppress cancer metastasis. Those progresses revealed the importance of ferroptosis in cancer, In order to provide the detailed molecular mechanisms of ferroptosis in regulating therapy resistance and metastasis and strategies to overcome these barriers are not fully understood, we described the key molecular mechanisms of ferroptosis and its interaction with signaling pathways related to therapy resistance and metastasis. Furthermore, we summarized strategies for reversing resistance to targeted therapy, chemotherapy, radiotherapy, and immunotherapy and inhibiting cancer metastasis by modulating ferroptosis. Understanding the comprehensive regulatory mechanisms and signaling pathways of ferroptosis in cancer can provide new insights to enhance the efficacy of anticancer drugs, overcome drug resistance, and inhibit cancer metastasis.

Peruvoside is a novel Src inhibitor that suppresses NSCLC cell growth and motility by downregulating multiple Src-EGFR-related pathways

The tyrosine kinase Src plays an essential role in the progression of many cancers and is involved in several epidermal growth factor receptor (EGFR)-mediated signalling pathways. To improve the efficacy of lung cancer treatments, this study aimed to identify novel compounds that can disrupt the Src-EGFR interaction and that are less dependent on EGFR status with wild-type and mutations than other compounds. We used the Src pY419 ELISA as the platform to screen a compound library of more than 400 plant-derived active ingredients and identified peruvoside as a candidate Src-EGFR crosstalk inhibitor. The effects of peruvoside were evaluated by western blotting, cell function assays, combination Index (CI)-isobologram analyses and in vivo experiments. Peruvoside significantly suppressed the phosphorylation of Src, EGFR, and signal transducer and activator of transcription 3 (STAT3) in a dose- and time-dependent manner and somewhat suppressed their protein expression. Cell function assays revealed that peruvoside inhibited the proliferation, invasion, migration, and colony formation of lung cancer cells in vitro and tumour growth in vivo. Furthermore, peruvoside sensitized gefitinib-resistant tumour cells (A549, PC9/gef and H1975) to gefitinib treatment, indicating that peruvoside may exert synergistic effects when used in combination with established therapeutic agents. Our data also demonstrated that the inhibitory effects of peruvoside on lung cancer progression might be attributed to its ability to regulate Src, phosphoinositide 3-kinase (PI3K), c-Jun N-terminal kinase (JNK), Paxillin, p130cas, and EGFR. Our findings suggest that peruvoside suppresses non-small-cell lung carcinoma (NSCLC) malignancy by downregulating multiple Src-related pathways and could serve as a potential base molecule for developing new anticancer drugs and therapeutic strategies for lung cancer.

Preclinical Models for Acquired Resistance to Third-Generation EGFR Inhibitors in NSCLC: Functional Studies and Drug Combinations Used to Overcome Resistance

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are currently recommended as first-line treatment for advanced non-small-cell lung cancer (NSCLC) with EGFR-activating mutations. Third-generation (3rd G) EGFR-TKIs, including osimertinib, offer an effective treatment option for patients with NSCLC resistant 1st and 2nd EGFR-TKIs. However, the efficacy of 3rd G EGFR-TKIs is limited by acquired resistance that has become a growing clinical challenge. Several clinical and preclinical studies are being carried out to better understand the mechanisms of resistance to 3rd G EGFR-TKIs and have revealed various genetic aberrations associated with molecular heterogeneity of cancer cells. Studies focusing on epigenetic events are limited despite several indications of their involvement in the development of resistance. Preclinical models, established in most cases in a similar manner, have shown different prevalence of resistance mechanisms from clinical samples. Clinically identified mechanisms include EGFR mutations that were not identified in preclinical models. Thus, NRAS genetic alterations were not observed in patients but have been described in cell lines resistant to 3rd G EGFR-TKI. Mainly, resistance to 3rd G EGFR-TKI in preclinical models is related to the activation of alternative signaling pathways through tyrosine kinase receptor (TKR) activation or to histological and phenotypic transformations. Yet, preclinical models have provided some insight into the complex network between dominant drivers and associated events that lead to the emergence of resistance and consequently have identified new therapeutic targets. This review provides an overview of preclinical studies developed to investigate the mechanisms of acquired resistance to 3rd G EGFR-TKIs, including osimertinib and rociletinib, across all lines of therapy. In fact, some of the models described were first generated to be resistant to first- and second-generation EGFR-TKIs and often carried the T790M mutation, while others had never been exposed to TKIs. The review further describes the therapeutic opportunities to overcome resistance, based on preclinical studies.

TP53 Co-Mutations in Advanced EGFR-Mutated Non-Small Cell Lung Cancer: Prognosis and Therapeutic Strategy for Cancer Therapy

Lung cancer is the leading cause of cancer-related deaths worldwide. As the most prevalent molecular mutation subtypes in non-small cell lung cancer (NSCLC), EGFR-TKIs are currently a standard first-line therapy for targeting the mutated EGFR in advanced NSCLC patients. However, 20-30% of this subset of patients shows primary resistance to EGFR-TKIs. Patients with co-mutations of EGFR and several other genes have a poor response to EGFR-TKIs, whereas the prognostic and predictive significance of EGFR/TP53 co-mutation in NSCLC patients remains controversial. Meanwhile, little is known about how to choose an optimal therapeutic strategy for this subset of patients. Presently, no drugs targeting TP53 mutations are available on the market, and some p53 protein activators are in the early stage of clinical trials. A combination of EGFR-TKIs with antiangiogenic agents or chemotherapy or other agents might be a more appropriate strategy to tackle the problem. In this review, we describe the prognostic and predictive value of EGFR/TP53 co-mutation in NSCLC patients, investigate the mechanisms of this co-mutation affecting the response to EGFR-TKIs, and further explore optimal regimens effectively to prolong the survival time of the NSCLC patients harboring this co-mutation.

Co-occurrence CDK4/6 amplification serves as biomarkers of de novo EGFR TKI resistance in sensitizing EGFR mutation non-small cell lung cancer

Despite the development of predictive biomarkers to shape treatment paradigms and outcomes, de novo EGFR TKI resistance advanced non-small cell lung cancer (NSCLC) remains an issue of concern. We explored clinical factors in 332 advanced NSCLC who received EGFR TKI and molecular characteristics through 65 whole exome sequencing of various EGFR TKI responses including; de novo (progression within 3 months), intermediate response (IRs) and long-term response (LTRs) (durability > 2 years). Uncommon EGFR mutation subtypes were significantly variable enriched in de novo resistance. The remaining sensitizing EGFR mutation subtypes (exon 19 del and L858R) accounted for 75% of de novo resistance. Genomic landscape analysis was conducted, focusing in 10 frequent oncogenic signaling pathways with functional contributions; cell cycle, Hippo, Myc, Notch, Nrf2, PI-3-Kinase/Akt, RTK-RAS, TGF-β, p53 and β-catenin/Wnt signaling. Cell cycle pathway was the only significant alteration pathway among groups with the FDR p-value of 6 × 10^-4. We found only significant q-values of < 0.05 in 7 gene alterations; CDK6, CCNE1, CDK4, CCND3, MET, FGFR4 and HRAS which enrich in de novo resistance [range 36-73%] compared to IRs/LTRs [range 4-22%]. Amplification of CDK4/6 was significant in de novo resistance, contrary to IRs and LTRs (91%, 27.9% and 0%, respectively). The presence of co-occurrence CDK4/6 amplification correlated with poor disease outcome with HR of progression-free survival of 3.63 [95% CI 1.80-7.31, p-value < 0.001]. The presence of CDK4/6 amplification in pretreatment specimen serves as a predictive biomarker for de novo resistance in sensitizing EGFR mutation.

miR-196a Upregulation Contributes to Gefitinib Resistance through Inhibiting GLTP Expression

Tyrosine kinase inhibitor (TKI) therapy has greatly improved lung cancer survival in patients with epidermal growth factor receptor (EGFR) mutations. However, the development of TKI-acquired resistance is the major problem to be overcome. In this study, we found that miR-196a expression was greatly induced in gefitinib-resistant lung cancer cells. To understand the role and mechanism of miR-196a in TKI resistance, we found that miR-196a-forced expression alone increased cell resistance to gefitinib treatment in vitro and in vivo by inducing cell proliferation and inhibiting cell apoptosis. We identified the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) bound to the promoter region of miR-196a and induced miR-196a expression at the transcriptional level. NRF2-forced expression also significantly increased expression levels of miR-196a, and was an upstream inducer of miR-196a to mediate gefitinib resistance. We also found that glycolipid transfer protein (GLTP) was a functional direct target of miR-196a, and downregulation of GLTP by miR-196a was responsible for gefitinib resistance. GLTP overexpression alone was sufficient to increase the sensitivity of lung cancer cells to gefitinib treatment. Our studies identified a new role and mechanism of NRF2/miR-196a/GLTP pathway in TKI resistance and lung tumor development, which may be used as a new biomarker (s) for TKI resistance or as a new therapeutic target in the future.

Hitting the Right Spot: Advances in the Treatment of NSCLC With Uncommon EGFR Mutations

An understanding of the biology of uncommon epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) is evolving. These mutations are important for the selection of targeted therapy and the development of resistance. The advent of genomic profiling has led to guideline-recommended molecular testing to identify patients with NSCLC who carry uncommon EGFR mutations to aid in the selection of appropriate targeted therapy. This article discusses the efficacy and safety of current and emerging targeted therapies for the treatment of uncommon EGFR mutations in NSCLC to aid in developing patient-specific treatment plans.

Kanglaite Combined With Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor Therapy for Stage III/IV Non-Small Cell Lung Cancer: A PRISMA-Compliant Meta-Analysis

Objective: Kanglaite(KLT), a type of Chinese medicine preparation, is considered as an adjuvant therapeutic option for malignant cancer treatment. This study aimed to systematically investigate the efficacy and safety of the combination of KLT and epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) for the treatment of stage III/IV non-small cell lung cancer.

Methods: Randomized controlled trials (RCTs) that compared KLT plus EGFR-TKI with EGFR-TKI alone for the treatment of stage III/IV non-small cell lung cancer were reviewed. Literature searches (up to July 10, 2021) were performed on PubMed, Web of Science, Cochrane Library, Embase, ClinicalTrials.gov, China National Knowledge Infrastructure (CNKI), Wanfang Database, and the Chinese Scientific Journal Database. Two researchers independently assessed the risk of bias with the tool of Cochrane Collaboration. RevMan 5.3.0 was used in the analysis of the included trial data.

Results: 12 RCTs recruiting 1,046 patients with stage III/IV NSCLC were included. Results showed that compared with EGFR-TKI alone, KLT plus EGFR-TKI significantly increased the disease control rate (DCR) (odds ratio [OR]=3.26; 95% confidence interval [CI]:2.22–4.77; p < 0.00001), the objective response rate (ORR) (OR=2.59; 95% CI:1.87–3.58; p < 0.00001) and Karnofsky performance status (KPS) (OR = 2.76; 95% CI:1.73–4.39; p < 0.00001). Furthermore, patient immunity was enhanced with KLT plus EGFR-TKI. The combined treatment increased the percentage of CD4 + T cells (weighted mean difference [WMD]=5.36; 95% CI:3.60–7.13; p < 0.00001),the CD4+/CD8 + ratio (WMD = 0.18; 95% CI: 0.08–0.27; p = 0.004), and percentage of NK cells (WMD=4.84; 95% CI: 3.66–6.02; p < 0.00001).With regard to drug toxicity, the occurrence rate of nausea and vomiting was significantly reduced by KLT plus EGFR-TKI (OR=0.37; 95% CI: 0.16–0.86; p = 0.02).

Conclusion: KLT plus EGFR-TKI was effective in treating stage III/IV non-small cell lung cancer. Thus, its application in these patients is worth promoting. Additional double-blind, well-designed and multicenter RCTs are required to confirm the efficacy and safety of this treatment.

An Observational Study to Assess the Molecular Epidemiology and Direct Medical Costs of Epidermal Growth Factor Receptor (EGFR) Mutations in Patients with Advanced EGFR Mutation-Positive Non-Small Cell Lung Cancer Treated with Afatinib in Real-World Clinical Settings in Greece

Purpose

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the preferred first-line option for patients with advanced, EGFR-mutant non-small cell lung cancer (NSCLC). Afatinib, a second-generation irreversible EGFR-TKI, has been extensively used in Greece in this setting; however, real-world data regarding molecular epidemiology and financial implications of afatinib use are lacking.

Materials and Methods

This was an observational, non-interventional, multicenter, retrospective cohort study, based on real-world data collected from the medical charts/records of patients treated with afatinib between 15/03/2015 and 25/06/2020 and were recorded on a web-based data capture system. Cox models were used to assess the prognostic significance of clinicopathological parameters with respect to clinical outcomes of interest. Cost analysis was conducted from a public third-payer perspective, and only direct medical costs reimbursed by the payer were considered.

Results

A total of 59 patients were treated with afatinib for their EGFR mutation-positive advanced NSCLC; the median age was 61 years (range: 37-91). Performance status was zero in 61%, and brain metastases were present in 13.6%. Forty-four patients (74.6%) had a deletion in exon 19 only, while nine (15.3%) had a mutation in exon 21, 8 of them in L858R and one in L861Q. At a median follow-up of 41.8 months (95% CI 35.9-51.4), the median PFS was 14.3 months (95% CI 12.2-16.4), and the median OS was 29 months (95% CI 25.6-33.4). Corresponding values for patients with deletion 19 only were 14.3 months (95% CI 11.5-18.5) and 28.1 months (95% CI 21.1-32.6), respectively. The mean expenditure for the treatment of each patient equals €25,333.68; with €21,865.06 being attributed to drug acquisition costs, €3325.35 to monitoring costs and €143.27 to adverse event treatment-related costs.

Conclusion

Long-term data in the real-world setting in Greece confirm activity, tolerability and cost-effectiveness of afatinib as first-line treatment of patients with advanced EGFR-mutant NSCLC.

Clinical Trial Registration

Clinicaltrials.gov NCT04640870.

Hype or hope - Can combination therapies with third-generation EGFR-TKIs help overcome acquired resistance and improve outcomes in EGFR-mutant advanced/metastatic NSCLC?

Three generations of epidermal growth factor receptor - tyrosine kinase inhibitors (EGFR-TKIs) have been developed for treating advanced/metastatic non-small cell lung cancer (NSCLC) patients harboring EGFR-activating mutations, while a fourth generation is undergoing preclinical assessment. Although initially effective, acquired resistance to EGFR-TKIs usually arises within a year due to the emergence of clones harboring multiple resistance mechanisms. Therefore, the combination of EGFR-TKIs with other therapeutic agents has emerged as a potential strategy to overcome resistance and improve clinical outcomes. However, results obtained so far are ambiguous and ideal therapies for patients who experience disease progression during treatment with EGFR-TKIs remain elusive. This review provides an updated landscape of EGFR-TKIs, along with a description of the mechanisms causing resistance to these drugs. Moreover, it discusses the current knowledge, limitations, and future perspective regarding the use of EGFR-TKIs in combination with other anticancer agents, supporting the need for bench-to-bedside approaches in selected populations.

Liquid biopsy uncovers distinct patterns of DNA methylation and copy number changes in NSCLC patients with different EGFR-TKI resistant mutations

Targeted therapy with tyrosine kinase inhibitors (TKI) provides survival benefits to a majority of patients with non-small cell lung cancer (NSCLC). However, resistance to TKI almost always develops after treatment. Although genetic and epigenetic alterations have each been shown to drive resistance to TKI in cell line models, clinical evidence for their contribution in the acquisition of resistance remains limited. Here, we employed liquid biopsy for simultaneous analysis of genetic and epigenetic changes in 122 Vietnamese NSCLC patients undergoing TKI therapy and displaying acquired resistance. We detected multiple profiles of resistance mutations in 51 patients (41.8%). Of those, genetic alterations in EGFR, particularly EGFR amplification (n = 6), showed pronounced genome instability and genome-wide hypomethylation. Interestingly, the level of hypomethylation was associated with the duration of response to TKI treatment. We also detected hypermethylation in regulatory regions of Homeobox genes which are known to be involved in tumor differentiation. In contrast, such changes were not observed in cases with MET (n = 4) and HER2 (n = 4) amplification. Thus, our study showed that liquid biopsy could provide important insights into the heterogeneity of TKI resistance mechanisms in NSCLC patients, providing essential information for prediction of resistance and selection of subsequent treatment.

A Real-World, Observational, Prospective Study to Assess the Molecular Epidemiology of Epidermal Growth Factor Receptor (EGFR) Mutations upon Progression on or after First-Line Therapy with a First- or Second-Generation EGFR Tyrosine Kinase Inhibitor in EGFR Mutation-Positive Locally Advanced or Metastatic Non-Small Cell Lung Cancer: The 'LUNGFUL' Study

Simple Summary

Non-small cell lung cancer (NSCLC) accounts for approximately 85% of lung cancer cases, with few patients carrying driver mutations in the gene encoding for epidermal growth factor receptor (EGFR). Advances in translational research have established EGFR tyrosine kinase inhibitors (TKIs) as the standard first-line therapy for NSCLC patients with activating EGFR mutations. The aim of our observational study was to assess the frequency of T790M acquired resistance and predictors of its presence, in patients with EGFR-mutated locally advanced or metastatic NSCLC who have progressed in the first-line EGFR-TKI treatment setting with first- or second-generation TKIs and have undergone molecular testing in tissue and/or plasma biopsy. The study highlights the challenges of performing tissue re-biopsy in routine care settings, which can lead to patients considered non-eligible for certain therapies from which they can benefit, and merits further actions from the healthcare community, in order to establish re-biopsy as a standard procedure.

Abstract

Background: Real-world data on the molecular epidemiology of EGFR resistance mutations at or after progression with first- or second-generation EGFR-TKIs in patients with advanced NSCLC are lacking. Methods: This ongoing observational study was carried out by 23 hospital-based physicians in Greece. The decision to perform cobas^®EGFR Mutation Test v2 in tissue and/or plasma at disease progression was made before enrollment. For patients with negative/inconclusive T790M plasma-based results, tissue re-biopsy could be performed. Results: Ninety-six (96) eligible patients were consecutively enrolled (median age: 67.8 years) between July-2017 and September-2019. Of the patients, 98% were tested upon progression using plasma and 2% using tissue/cytology biopsy. The T790M mutation was detected in 16.0% of liquid biopsies. Tissue re-biopsy was performed in 22.8% of patients with a T790M-negative plasma result. In total, the T790M positivity rate was 21.9%, not differing between patients on first- or second-generation EGFR-TKI. Higher (≥2) ECOG performance status and longer (≥10 months) time to disease progression following EGFR-TKI treatment initiation were associated with T790M positivity. Conclusions: Results from plasma/tissue-cytology samples in a real-world setting, yielded a T790M positivity rate lower than previous reports. Fewer than one in four patients with negative plasma-based testing underwent tissue re-biopsy, indicating the challenges in routine care settings.

Predictive value of pretreatment PD-L1 expression in EGFR-mutant non-small cell lung cancer: a meta-analysis

Objective

To investigate the predictive value of programmed death-ligand 1 (PD-L1) expression in non-small cell lung cancer (NSCLC) patients treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs).

Methods

We conducted a systemic search of PubMed, EMBASE, and the Cochrane Library from 1 January 2000 to 30 August 2020, to identify related studies. We combined the hazard ratio (HR) and 95% confidence interval (CI) to assess the correlation of PD-L1 expression with progression-free survival (PFS) and overall survival (OS). We assessed the quality of the included studies by the Newcastle–Ottawa Scale (NOS). We performed subgroup analyses based on immunohistochemistry (IHC) scoring system, IHC antibodies, sample size, countries, and survival analysis mode. Sensitivity analysis and evaluation of publication bias were also performed.

Results

Twelve studies including 991 patients met the criteria. The mean NOS score was 7.42 ± 1.19. Patients with high PD-L1 expression was associated with poorer PFS (HR = 1.90; 95% CI = 1.16–3.10; P = 0.011), while there was no association between PD-L1 expression and OS (HR = 1.19; 95% CI = 0.99–1.43; P = 0.070). Subgroup analysis prompted IHC scoring systems, IHC antibodies, and sample size have important effects on heterogeneity. The pooled results were robust according to the sensitivity analysis.

Conclusions

The result of this meta-analysis suggested that PD-L1 expression might be a predictive biomarker for EGFR-mutant non-small cell lung cancer treated with EGFR-TKIs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02254-x.

Targeting histone deacetylase enhances the therapeutic effect of Erastin-induced ferroptosis in EGFR-activating mutant lung adenocarcinoma

Background

Intrinsic or acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is common, thus strategies for the management of EGFR-TKIs resistance are urgently required. Ferroptosis is a recently discovered form of cell death that has been implicated in tumorigenesis and resistance treatment. Accumulating evidence suggests that ferroptosis can be therapeutically exploited for the treatment of solid tumors; however, whether ferroptosis can be targeted to treat EGFR mutant lung cancer and/or overcome the resistance to EGFR-TKIs is still unknown.

Methods

The effect of ferroptosis inducers on a panel of EGFR mutant lung cancer cell lines, including those with EGFR-TKI intrinsic and acquired (generated by long-term exposure to the third-generation EGFR-TKI osimertinib), was determined using cytotoxicity assays. Further, drug candidates to enhance the effect of ferroptosis inducers were screened through implementing WGCNA (weighted gene co-expression network analysis) and CMAP (connectivity map) analysis. Flow cytometry-based apoptosis and lipid hydroperoxides measurement were used to evaluate the cell fates after treatment.

Results

Compared with EGFR-TKI-sensitive cells, those with intrinsic or acquired resistance to EGFR-TKI display high sensitivity to ferroptosis inducers. In addition, Vorinostat, a clinically used inhibitor targeting histone deacetylase, can robustly enhance the efficacy of ferroptosis inducers, leading to a dramatic increase of hydroperoxides in EGFR mutant lung cancer cells with intrinsic or acquired resistance to EGFR-TKI. Mechanistically, Vorinostat promotes ferroptosis via xCT downregulation.

Conclusions

Ferroptosis-inducing therapy shows promise in EGFR-activating mutant lung cancer cells that display intrinsic or acquired resistance to EGFR-TKI. Histone deacetylase inhibitor (HDACi) Vorinostat can further promote ferroptosis by inhibiting xCT expression.

Computational Analysis of Drug Resistance Network in Lung Adenocarcinoma

BACKGROUND

Lung cancer is a significant health problem and accounts for one-third of the deaths worldwide. A great majority of these deaths are caused by non-small cell lung cancer (NSCLC). Chemotherapy is the leading treatment method for NSCLC, but resistance to chemotherapeutics is an important limiting factor that reduces the treatment success of patients with NSCLC.

OBJECTIVE

In this study, the relationship between differentially expressed genes affecting the survival of the patients, according to the bioinformatics analyses, and the mechanism of drug resistance is investigated for non-small cell lung adenocarcinoma patients.

METHODS

Five hundred thirteen patient samples were compared with fifty-nine control samples. The employed dataset was downloaded from The Cancer Genome Atlas (TCGA) database. The information on how the drug activity altered against the expressional diversification of the genes was extracted from the NCI-60 database. Four hundred thirty-three drugs with known mechanism of action (MoA) were analyzed. Diversifications of the activity of these drugs related to genes were considered based on nine lung cancer cell lines virtually. The analyses were performed using R programming language, GDCRNATools, rcellminer, and Cytoscape.

RESULTS

This work analyzed the common signaling pathways and expressional alterations of the proteins in these pathways associated with survival and drug resistance in lung adenocarcinoma. Deduced computational data demonstrated that proteins of EGFR, JNK/MAPK, NF-κB, PI3K /AKT/mTOR, JAK/STAT, and Wnt signaling pathways were associated with molecular mechanism of resistance to anticancer drugs in NSCLC cells.

CONCLUSION

To understand the relationships between resistance to anticancer drugs and EGFR, JNK/MAPK, NF-κB, PI3K /AKT/mTOR, JAK/STAT, and Wnt signaling pathways is an important approach to design effective therapeutics for individuals with NSCLC adenocarcinoma.

Molecular mechanism and pharmacokinetics of flavonoids in the treatment of resistant EGF receptor-mutated non-small-cell lung cancer: A narrative review

Here, we review the molecular mechanism and pharmacokinetics of flavonoids in the treatment of resistant EGF receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) and particularly the possible mechanism(s) of delicaflavone, a biflavonoid extracted from Selaginella doederleinii Hieron. EGFR TK inhibitors (EGFR-TKI) are ubiquitously used in the treatment of NSCLC bearing EGFR mutations. However, patients treated with EGFR-TKI inevitably and continuously develop resistance. In laboratory studies, flavonoids, as potential adjuvants for cancer chemotherapy, exhibited anti-cancer properties such as inhibition of chemoresistance by interference with ABC transporters-induced drug efflux, curbing of c-MET amplification, or reversal of T790M mutation-mediated resistance. The current review aims at summarizing the association between the anti-cancer potentials of flavonoids and their possible regulatory roles in certain types of mutation that could trigger EGFR-TKI resistance in NSCLC. Potential practical applications of these phytochemicals, as well as the relevant pharmacokinetics, are also discussed.

RNA methyltransferase METTL3 induces intrinsic resistance to gefitinib by combining with MET to regulate PI3K/AKT pathway in lung adenocarcinoma

Clinical research data show that gefitinib greatly improves the progression‐free survival of patients, so it is used in advanced non‐small cell lung cancer patients with EGFR mutation. However, some patients with EGFR sensitive mutations do not have good effects on initial gefitinib treatment, and this mechanism is rarely studied. METTL3, a part of N6‐adenosine‐methyltransferase, has been reported to play an important role in a variety of tumours. In this study, we found that METTL3 is up‐regulated in gefitinib‐resistant tissues compared to gefitinib‐sensitive tissues. Cell function experiments have proved that under the treatment of gefitinib, METTL3 knockdown promotes apoptosis and inhibits proliferation of lung cancer cells. Mechanistic studies have shown that METTL3 combines with MET and causes the PI3K/AKT signalling pathway to be manipulated, which affects the sensitivity of lung cancer cells to gefitinib. Therefore, our research shows that METTL3 can be used as a molecular marker to predict the efficacy of EGFR‐TKI therapy in patients, and METTL3 may be a potential therapeutic target.

The emergence of various genetic alterations mediated the Osimertinib resistance of a patient harboring heterozygous germline EGFR T790M: a case report

Epidermal growth factor receptor (EGFR) T790M is the major mechanism mediating resistance to first- and second-generation EGFR tyrosine kinase inhibitors. Despite the high frequency of EGFR activating mutations among East Asian lung cancer patients, germline T790M has been the subject of very little research. Questions remain as to whether germline T790M develops resistance to Osimertinib and if so, through which mechanisms. This study examined a patient harboring germline EGFR T790M who acquired resistance to Osimertinib therapy. After the failure of first-line icotinib therapy, which was administered for only 3 months, targeted next-generation sequencing of plasma samples collected at icotinib progression and the re-analysis of the baseline tissue biopsy sample revealed EGFR T790M with allelic frequencies approximating 50%. Lymphocyte genomic deoxyribonucleic acid (DNA) sequencing confirmed the germline heterozygous status of the T790M mutation. In addition to the EGFR T790M, a concurrent EGFR L858R was detected from the baseline tissue sample. Osimertinib therapy was initiated resulting in a partial response within 1 month of the commencement of the therapy. After 15.2 months of Osimertinib therapy, disease progression was evaluated due to the presence of pleural effusion. The targeted sequencing of plasma and pleural effusion samples revealed the emergence of EGFR G719A, tumor protein p53 (TP53) Q136X, and the co-amplification of Cyclin D1, fibroblast growth factor (FGF) 19, FGF3, and FGF4. This case highlights the importance of conducting next-generation sequencing–based molecular testing during both diagnostic and disease progression assessments to reveal sensitizing mutations and mutations that could mediate primary and acquired resistance to targeted therapeutics.

Mechanism of intrinsic resistance of lung squamous cell carcinoma to epithelial growth factor receptor-tyrosine kinase inhibitors revealed by high-throughput RNA interference screening

Although targeted therapy has achieved a great breakthrough in the treatment of lung adenocarcinoma, there are still no effective targeted drugs for lung squamous cell carcinoma (SqCC). In addition, as immunotherapy can only prolong the overall survival (OS) of lung SqCC by ≤5 months, chemotherapy and radiotherapy are still the main types of therapy for advanced SqCC. The expression level of epithelial growth factor receptor (EGFR) in patients with lung SqCC is higher compared with those with adenocarcinoma, but the former group is intrinsically resistant to EGFR-tyrosine kinase inhibitors (EGFR-TKIs). Therefore, if the drug resistance in patients with lung SqCC could be reversed, the majority of patients may benefit from EGFR-TKIs. In the present study, the high-throughput RNA interference technology was used to screen the genes involved in the EGFR-TKI erlotinib resistance of lung SqCCs, and integrin-linked kinase (ILK) was identified to be the most effective. The role of ILK in erlotinib resistance was further studied in cell lines, and the expression of ILK was analyzed in patients with SqCC and adenocarcinoma. Finally, the mechanism of ILK in EGFR-TKIs resistance was analyzed using Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO) and ingenuity pathway analysis (IPA). The results demonstrated that the ILK gene knockdown could overcome erlotinib resistance by inhibiting cell proliferation, inducing apoptosis and blocking the cell cycle at the G2/M phase. The expression of ILK in patients with SqCC was significantly higher compared with those with adenocarcinoma with sensitizing EGFR mutations. In addition, the cell cycle pathway 'G2/M DNA damage and checkpoint regulation' was identified to be significantly inhibited by ILK knockdown in IPA, KEGG and GO analysis. The results of the present study may improve the understanding of EGFR-TKI resistance in lung SqCCs, thus promoting the development of potential targeted therapies for lung SqCCs.

Mechanisms of resistance in head and neck cancer

Resistance to treatment is one of the biggest challenges in combating head and neck squamous cell carcinoma (HNSCC). The concept of resistance, however, is often viewed as a whole without categorization into the two types of resistance: acquired and intrinsic. Comparison of the mechanisms of the two types of resistance can give further insight as to the importance of these resistance pathways, as mechanisms that are common between the two categories are more likely to be integral to cell survival. In this review, a new perspective on resistance is presented in order to identify molecular targets that have potential for wide therapeutic application. Resistance mechanisms are grouped by the primary pathway involved in order to help establish connections between studies and identify the pathways most active in HNSCC resistance. The receptor tyrosine kinase AXL is one of the targets that showed the greatest promise for overcoming resistance to cetuximab, an antibody targeting the epidermal growth factor receptor (EGFR), as it is shown to be upregulated in both acquired and intrinsically cetuximab-resistant cells. Other targets of interest are signal transducer and activator of transcription 3 (STAT3), a downstream transcription factor of the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, and TWIST, a marker of epithelial-mesenchymal transition. STAT3 has been shown to be upregulated and more active in cetuximab-resistant HNSCC cell lines, and its inhibition decreased cell growth in cell lines resistant to anti-EGFR therapy. Twist has been shown to have roles in acquired resistance for both cetuximab and cisplatin, a platinum-based therapy that targets dividing cells, which suggests that it also has an integral role in resistance. Other resistance mechanisms are also summarized in this review, but further studies are needed in order to confirm their utility as targets for overcoming resistance in HNSCC.

Current Strategies for Treating NSCLC: From Biological Mechanisms to Clinical Treatment

The identification of specific epidermal growth factor receptor (EGFR)-activating mutations heralded a breakthrough in non-small-cell lung cancer (NSCLC) treatments, with the subsequent development of EGFR-tyrosine kinase inhibitor (TKIs) becoming the first-line therapy for patients harboring EGFR mutations. However, acquired resistance to EGFR-TKIs inevitably occurs in patients following initial TKI treatment, leading to disease progression. Various mechanisms are behind the acquired resistance, and mainly include (1) target gene modification, (2) alternative parallel pathway activation, (3) downstream pathway activation, and (4) histological/phenotypic transformation. Approaches to combat the acquired resistance have been investigated according to these mechanisms. Newer generations of TKIs have been developed to target the secondary/tertiary EGFR mutations in patients with acquired resistance. In addition, combination therapies have been developed as another promising strategy to overcome acquired resistance through the activation of other signaling pathways. Thus, in this review, we summarize the mechanisms for acquired resistance and focus on the potential corresponding therapeutic strategies for acquired resistance.

Real-world assessment of afatinib for patients with EGFR-positive non-small cell lung cancer

Introduction Afatinib is used to treat patients with advanced non-small cell lung cancer (NSCLC) harboring common EGFR mutations; however, the clinicopathological factors that predict this drug's effectiveness in real-world settings remain unclear. We therefore evaluated the effectiveness of afatinib in such patients and assessed potential prognostic factors. Methods We retrospectively investigated patients with NSCLC who received first-line afatinib between July 2014 and August 2018. Variables (including sex, age, performance status, neutrophil-to-lymphocyte ratio, EGFR genotype, smoking status, clinical stage prior to treatment [stage IV vs.. postoperative recurrence], presence or absence of brain metastases, body surface area, any afatinib dose reductions, and afatinib starting dose [40 vs.. 20 or 30 mg]) were subjected to a Cox proportional hazards regression model to estimate progression-free survival (PFS). Results Forty-eight patients with a median age of 67 years were included; the objective response rate was 62.5% (30 patients). The median PFS was 14.1 months; the PFS periods were 11.8 and 15.9 months for patients receiving 40 mg versus 20-30 mg of afatinib (P = 0.41), respectively, and were 14.5 and 13.8 months for patients who required afatinib dose reduction and those who did not, respectively (P = 0.80). The PFS tended to be longer in patients without brain metastases (albeit not significantly). Ultimately, no significant predictive values for PFS were identified. Conclusions Afatinib is effective for patients with NSCLC harboring common EGFR mutations irrespective of their clinicopathological backgrounds. A direct comparison of afatinib and osimertinib in treatment-naïve patients is warranted to determine the optimal standard of care.

[Genetic Profile of Young Chinese Patients with Lung Adenocarcinoma]

背景与目的

全球肺癌的发病率正呈逐年上升趋势，其中腺癌所占的百分比日益升高。据统计，全球的肺癌平均初诊年龄在70岁左右，虽然肺癌仍以老年患者居多，但发病年龄的年轻化趋势愈加明显。结合现有研究数据，我们已知在非小细胞肺癌中，年轻患者疾病的发生有其独特的生物学特点。但年轻肺腺癌患者的基因组学特性和临床特征仍有待确定。本研究采用高通量测序（next-generation sequencing technology, NGS）技术对中国年轻肺腺癌患者的基因突变状态进行了研究。

方法

共收集了89例年龄≤45岁的肺腺癌患者组织标本，所有患者均知情同意。使用NGS检测用于确定癌组织中驱动基因突变。此外，对同期行NGS检测的95例 > 45岁肺腺癌患者的基因组和临床病理特征进行回顾性分析。

结果

根据年龄分类对184例肺腺癌患者的驱动基因突变频率进行了分析，揭示了年龄≤45岁的年轻组患者的独特基因特征。其中间变淋巴瘤激酶（anaplastic lymphoma kinase, ALK）融合基因和人表皮生长因子受体-2（human epidermal growth factor receptor 2, HER2）基因的突变频率较高。而鼠类肉瘤病毒癌基因（kirsten rat sarcoma viral oncogene, KRAS）、丝氨酸/苏氨酸蛋白激酶11（serine/threonine kinase 11, STK11）和表皮生长因子受体（epidermal growth factor receptor, EGFR）20外显子突变的趋势则相反，这些突变在年龄 > 45岁的老年组中更为常见。此外，年轻组EGFR基因突变同时伴有肿瘤蛋白p53（tumor protein p53, TP53）基因突变较老年组更为普遍（81.6% vs 44.9%），这可能使其应用EGFR酪氨酸激酶抑制剂（EGFR-tyrosine kinase inhibitor, EGFR-TKI）后疗效较差。

结论

NGS分析显示年轻腺癌患者具有独特的基因突变特点。在年轻患者中发现EGFR/TP53共突变的频率较高，这些独特的基因组学特征对临床治疗有重要的指导意义。

Emerging non-invasive detection methodologies for lung cancer

The potential for non-invasive lung cancer (LC) diagnosis based on molecular, cellular and volatile biomarkers has been attracting increasing attention, with the development of advanced techniques and methodologies. It is standard practice to tailor the treatments of LC for certain specific genetic alterations, including the epidermal growth factor receptor, anaplastic lymphoma kinase and BRAF genes. Despite these advances, little is known about the internal mechanisms of different types of biomarkers and the involvement of their related biochemical pathways during the development of LC. The development of faster and more effective techniques is essential for the identification of different biomarkers. The present review summarizes some of the latest methods used for detecting molecular, cellular and volatile biomarkers in LC and their potential use in clinical diagnosis and targeted therapy.

Involvement of the TNF-α Pathway in TKI Resistance and Suggestion of TNFR1 as a Predictive Biomarker for TKI Responsiveness in Clear Cell Renal Cell Carcinoma

BACKGROUND

Mechanism and predictive biomarkers for tyrosine kinase inhibitor (TKI) resistance of advanced clear cell renal cell carcinoma (ccRCC) have not been fully evaluated.

METHODS

We performed gene expression profiling on samples from an acquired TKI resistance cohort that consisted of 10 cases of TKI-treated ccRCC patients with matched tumor tissues harvested at pre-treatment and TKI-resistant post-treatment periods. In addition, a public microarray dataset from patient-derived xenograft model for TKI-treated ccRCC (GSE76068) was retrieved. Commonly altered pathways between the datasets were investigated by Ingenuity Pathway Analysis using commonly regulated differently expressed genes (DEGs). The significance of candidate DEG on intrinsic TKI resistance was assessed through immunohistochemistry in a separate cohort of 101 TKI-treated ccRCC cases.

RESULTS

TNFRSF1A gene expression and tumor necrosis factor (TNF)-α pathway were upregulated in ccRCCs with acquired TKI resistance in both microarray datasets. Also, high expression (> 10% of labeled tumor cells) of TNF receptor 1 (TNFR1), the protein product of TNFRSF1A gene, was correlated with sarcomatoid dedifferentiation and was an independent predictive factor of clinically unfavorable response and shorter survivals in separated TKI-treated ccRCC cohort.

CONCLUSION

TNF-α signaling may play a role in TKI resistance, and TNFR1 expression may serve as a predictive biomarker for clinically unfavorable TKI responses in ccRCC.

Potential mechanism of primary resistance to icotinib in patients with advanced non-small cell lung cancer harboring uncommon mutant epidermal growth factor receptor: A multi-center study

The incidence of epidermal growth factor receptor uncommon mutation (EGFRum) is relatively low and patients harboring EGFRum are resistant to the first-generation tyrosine kinase inhibitors (TKI). However, the mechanism of primary resistance remains unclear. Medical records of 98 patients who had never been treated by TKI and who accepted icotinib treatment were collected and followed. The circulating tumor DNA (ctDNA) were detected and analyzed using the next-generation sequencing (NGS) platform after progression on icotinib. The potential primary resistance mechanism of icotinib was explored. A total of 21 (21.4%) and 48 (49%) patients developed primary and acquired resistance to icotinib, respectively. The median progression-free survival (PFS) of primary resistance patients was 1.8 months (0.5-2.3, 95% CI = 1.50-2.10). Before treatment, 52.4% (11/21) of patients carried S768I, 23.8% (5/21) L861Q, 14.3% (3/21) G719X and 14.3% (3/21) exon 20-ins mutations. Approximately 23.8% (5/21) of patients harbored the combined pattern mutations and 76.2% (16/21) of patients harbored the single pattern mutations. The combined pattern with EGFR classical mutation (EGFRcm) had worse PFS than the combined with EGFRum and single pattern (P < .05). There were 6 (28.57%) patients with acquired EGFR extracellular domain mutation, 5 (23.81%) with BCL2L11 loss (BIM deletion polymorphism), 3 (14.29%) with MET amplification, 1 (4.76%) with ERBB2 amplification, 1 (4.76%) with MYC amplification, 1 (4.76%) with PTEN mutation, 1 (4.76%) with PIK3CA mutation and 3 (14.29%) with unknown status. EGFR extracellular domain mutation, BCL2L11 loss, PI3K-AKT-mTOR signaling pathway (PTEN and PIK3CA mutations), MET amplification, ERBB2 amplification or MYC amplification might contribute to molecular mechanisms of primary resistance to icotinib in patients with advanced non-small cell lung cancer harboring uncommon mutant epidermal growth factor receptor. Combined targeted therapy or chemotherapy should be considered in this population.