Altered Regulation of HIF-1α in Naive- and Drug-Resistant EGFR-Mutant NSCLC: Implications for a Vascular Endothelial Growth Factor-Dependent Phenotype

The HIF-1α/PKM2 Feedback Loop in Relation to EGFR Mutational Status in Lung Adenocarcinoma

OBJECTIVE

Gene mutations in tumor cells can lead to several unique metabolic phenotypes, which are crucial for the proliferation of cancer cells. EGFR mutation (EGFR-mt) is the main oncogenic driving mutation in lung adenocarcinoma (LUAD). HIF-1 α and PKM2 are two key metabolic regulatory proteins that can form a feedback loop and promote cancer growth by promoting glycolysis. Here, the linkage between EGFR mutational status and HIF-1α/PKM2 feedback loop in LUAD were evaluated.

METHODS

Retrospective study were performed on LUAD patients (n = 89) undergoing first-time therapeutic surgical resection. EGFR mutation was analyzed by real-time PCR. Immunohistochemistry was used to measure the expressions of HIF-1α and PKM2.

RESULTS

We found that the protein expressions of HIF-1α and PKM2 were significantly higher in LUAD than normal lung tissues. In adenocarcinomas, the two protein expressions were both correlated with worse pTNM stage. Moreover, the correlation between the proteins of HIF-1α/PKM2 feedback loop and the EGFR mutational status were also analyzed. We found that EGFR-mt tumors showed higher HIF-1α and PKM2 proteins compared to tumors with EGFR wild-type. Meanwhile, HIF-1α expression was significantly correlated with higher pTNM stage, and PKM2 showed a similar trend, only in EGFR-mutated tumors. The expression of HIF-1α was positively correlated with PKM2 in LUAD, furthermore, this correlation was mainly in patients with EGFR-mt.

CONCLUSION

Different expression and clinical features of HIF-1α/PKM2 feedback loop was existed between LUAD and normal lung tissues, especially in EGFR mutational tumors, supporting the relationship between EGFR mutation and the key related proteins of aerobic glycolysis (HIF-1α and PKM2) in lung adenocarcinomas.

Decoding the mechanism of earthworm extract against wounds: an integrated metabolomics and network pharmacology study

Earthworms are used to cure wounds in Chinese villages for thousands of years. Recently, scientists realized their extracts could promote wound healing and they have anti-inflammatory, antioxidant, anti-apoptosis, and anti-microbial properties, but its mechanism of promoting wound healing remains unclear. In the presented study, electronic literature databases and LC-MS/MS were used to determine earthworms' ingredients and differential metabolites. Swiss Target Prediction database was used for ingredients' target prediction and wound disease-relevant genes were found from GeneCards, OMIM, and DrugBank databases. Network pharmacology was conducted to demonstrate filtering hub targets, biological functions, and the signaling pathways of earthworms extract against wounds. Molecular docking and metabolism analysis were used to look for core target genes and key bioactive molecules from earthworms. Finally, the investigation shows 5 most important signal pathways, 5 core genes, and 6 bioactive ingredients-related cell-cell adhesion, cell proliferation, and cell migration processes could be affected by earthworms' extract. On 3rd day, the extract could regulate HIF1A and EGFR targets to make the differences of quantities of 4-pyridoxate, tetradecanoic acid, and L-kynurenine. While on 7th day, the regulation refers 6 earthworms' bioactive ingredients, 4 core genes (CTNNB1, EGFR, SRC, and CASP3), and 4 differential metabolites (4-hydoxy-2-quinolinecarboxylic acid, urocanate, deoxyinosine, creatine, and sn-glycerol-3-phosphocholine). on 14th day, 2 core genes (EGFR, SRC) are influenced in the biological processes. Briefly, we found that 6 ingredients from earthworms have most bioactive and 5 core genes play an important role in promoting wound-healing processes. These discovers indicates earthworms could against wound via AGE-RAGE, PI3K-Akt, HIF1A, MAPK, and Axon guidance pathways.

Lipocalin 2 (LCN2) confers acquired resistance to almonertinib in NSCLC through LCN2-MMP-9 signaling pathway

Almonertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is highly selective for EGFR-activating mutations as well as the EGFR T790M mutation in patients with advanced non-small cell lung cancer (NSCLC). However, the development of resistance inevitably occurs and poses a major obstacle to the clinical efficacy of almonertinib. Therefore, a clear understanding of the mechanism is of great significance to overcome drug resistance to almonertinib in the future. In this study, NCI-H1975 cell lines resistant to almonertinib (NCI-H1975 AR) were developed by concentration-increasing induction and were employed for clarification of underlying mechanisms of acquired resistance. Through RNA-seq analysis, the HIF-1 and TGF-β signaling pathways were significantly enriched by gene set enrichment analysis. Lipocalin-2 (LCN2), as the core node in these two signaling pathways, were found to be positively correlated to almonertinib-resistance in NSCLC cells. The function of LCN2 in the drug resistance of almonertinib was investigated through knockdown and overexpression assays in vitro and in vivo. Moreover, matrix metalloproteinases-9 (MMP-9) was further identified as a critical downstream effector of LCN2 signaling, which is regulated via the LCN2-MMP-9 axis. Pharmacological inhibition of MMP-9 could overcome resistance to almonertinib, as evidenced in both in vitro and in vivo models. Our findings suggest that LCN2 was a crucial regulator for conferring almonertinib-resistance in NSCLC and demonstrate the potential utility of targeting the LCN2-MMP-9 axis for clinical treatment of almonertinib-resistant lung adenocarcinoma.

Potential roles of tumor microenvironment in gefitinib-resistant non-small cell lung cancer: A narrative review

During the course of treating non-small cell lung cancer (NSCLC) with epithelial growth factor receptor (EGFR) mutant, gefitinib resistance (GR) is unavoidable. As the environment for tumor cells to grow and survive, tumor microenvironment (TME) can significantly affect therapeutic response and clinical outcomes, offering new opportunities for addressing GR. Dynamic changes within the TME were identified during the treatment of gefitinib, suggesting the close relationship between TME and GR. Various dynamic processes like angiogenesis, hypoxia-pathway activation, and immune evasion can be blocked so as to synergistically enhance the therapeutic effects of gefitinib or reverse GR. Besides, cellular components like macrophages can be reprogrammed for the same purpose. In this review, we summarized recently proposed therapeutic targets to provide an overview of the potential roles of TME in treating gefitinib-resistant NSCLC, and discussed the difficulty of applying these targets in cancer treatment.

The Anti-atherosclerosis Mechanism of Ziziphora clinopodioides Lam. Based On Network Pharmacology

We investigated the mechanisms underlying the effects of Ziziphora clinopodioides Lam. (ZCL) on atherosclerosis (AS) using network pharmacology and in vitro validation.We collected the active components of ZCL and predicted their targets in AS. We constructed the protein-protein interaction, compound-target, and target-compound-pathway networks, and performed GO and KEGG analyses. Molecular docking of the active components and key targets was constructed with Autodock and Pymol software. Validation was performed with qRT-PCR, ELISA, and Western blot.We obtained 80 components of ZCL. The network analysis identified that 14 components and 37 genes were involved in AS. Then, 10 key nodes in the PPI network were identified as the key targets of ZCL because of their importance in network topology. The binding energy of 8 components (Cynaroside, α-Spinasterol, Linarin, Kaempferide, Acacetin, Genkwanin, Chrysin, and Apiin) to 4 targets (MMP9, TP53, AKT1, SRC) was strong and <-1 kJ/mol. In addition, 13 of the 14 components were flavonoids and thus total flavonoids of Ziziphora clinopodioides Lam. (ZCF) were used for in vitro validation. We found that ZCF reduced eNOS, P22phox, gp91phox, and PCSK9 at mRNA and protein levels, as well as the levels of IL-1β, TNF-α, and IL-6 proteins in vitro (P < 0.05).We successfully predicted the active components, targets, and mechanisms of ZCL in treating AS using network pharmacology. We confirmed that ZCF may play a role in AS by modulating oxidative stress, lipid metabolism, and inflammatory response via Cynaroside, Linarin, Kaempferide, Acacetin, Genkwanin, Chrysin, and Apiin.

Ramucirumab plus erlotinib versus placebo plus erlotinib in previously untreated EGFR-mutated metastatic non-small-cell lung cancer (RELAY): exploratory analysis of next-generation sequencing results

BACKGROUND

Ramucirumab plus erlotinib (RAM + ERL) demonstrated superior progression-free survival (PFS) over placebo + ERL (PBO + ERL) in the phase III RELAY study of patients with epidermal growth factor receptor (EGFR)-mutated metastatic non-small-cell lung cancer (EGFR+ mNSCLC; NCT02411448). Next-generation sequencing (NGS) was used to identify clinically relevant alterations in circulating tumor DNA (ctDNA) and explore their impact on treatment outcomes.

PATIENTS AND METHODS

Eligible patients with EGFR+ mNSCLC were randomized 1 : 1 to ERL (150 mg/day) plus RAM (10 mg/kg)/PBO every 2 weeks. Liquid biopsies were to be prospectively collected at baseline, cycle 4 (C4), and postdiscontinuation follow-up. EGFR and co-occurring/treatment-emergent (TE) genomic alterations in ctDNA were analyzed using Guardant360 NGS platform.

RESULTS

In those with valid baseline samples, detectable activating EGFR alterations in ctDNA (aEGFR+) were associated with shorter PFS [aEGFR+: 12.7 months (n = 255) versus aEGFR-: 22.0 months (n = 131); hazard ratio (HR) = 1.87, 95% confidence interval (CI) 1.42-2.51]. Irrespective of detectable/undetectable baseline aEGFR, RAM + ERL was associated with longer PFS versus PBO + ERL [aEGFR+: median PFS (mPFS) = 15.2 versus 11.1 months, HR = 0.63, 95% CI 0.46-0.85; aEGFR-: mPFS = 22.1 versus 19.2 months, HR = 0.80, 95% CI 0.49-1.30]. Baseline alterations co-occurring with aEGFR were identified in 69 genes, most commonly TP53 (43%), EGFR (other than aEGFR; 25%), and PIK3CA (10%). PFS was longer in RAM + ERL, irrespective of baseline co-occurring alterations. Clearance of baseline aEGFR by C4 was associated with longer PFS (mPFS = 14.1 versus 7.0 months, HR = 0.481, 95% CI 0.33-0.71). RAM + ERL improved PFS outcomes, irrespective of aEGFR mutation clearance. TE gene alterations were most commonly in EGFR [T790M (29%), other (19%)] and TP53 (16%).

CONCLUSIONS

Baseline aEGFR alterations in ctDNA were associated with shorter mPFS. RAM + ERL was associated with improved PFS outcomes, irrespective of detectable/undetectable aEGFR, co-occurring baseline alterations, or aEGFR+ clearance by C4. aEGFR+ clearance by C4 was associated with improved PFS outcomes. Monitoring co-occurring alterations and aEGFR+ clearance may provide insights into mechanisms of EGFR tyrosine kinase inhibitor resistance and the patients who may benefit from intensified treatment schedules.

Integrated bioinformatics analysis for exploring hub genes and related mechanisms affecting the progression of gastric cancer

Objective Gastric cancer (GC) is a high-risk tumor disease worldwide. The goal of the current study was to explore new diagnostic and prognostic indicators for gastric cancer. Methods Database GSE19826 and GSE103236 were gained from the Gene Expression Omnibus (GEO) to screen for differentially expressed genes (DEGs), which were then grouped together as co-DEGs. GO and KEGG pathway analysis were used to investigate the function of these genes. The protein-protein interaction (PPI) network of DEGs was constructed by STRING. Results GSE19826 selected 493 DEGs in GC and gastric normal tissues, including 139 up-regulated genes and 354 down-regulated genes. A total of 478 DEGs were selected by GSE103236, including 276 up-regulated genes and 202 downregulated genes. 32 co-DEGs were overlapped from two databasesand involved in digestion, regulation of response to wounding, wound healing, potassium ion imports across plasma membrane, regulation of wound healing, anatomical structure homeostasis, and tissue homeostasis. KEGG analysis revealed that co-DEGs were mainly involved in ECM-receptor interaction, tight junction, protein digestion and absorption, gastric acid secretion and cell adhesion molecules. Twelve hub genes were screened by Cytoscape, including cholecystokinin B receptor (CCKBR), Collagen type I alpha 1 (COL1A1), COL1A2, COL2A1, COL6A3, COL11A1, matrix metallopeptidase 1 (MMP1), MMP3, MMP7, MMP10, tissue inhibitor of matrix metalloprotease 1 (TIMP1) and secreted phosphoprotein 1 (SPP1). Conclusions Twelve key genes affecting the progression of gastric cancer were obtained by bioinformatics, which may be potential biomarkers for the diagnosis and prognosis of GC.

Effects of Aidi injection on life quality and incidence of adverse reactions in patients with non-small cell lung cancer compared with traditional chemotherapy: a systematic review and meta-analysis

Objective

Although the clinical application value of Aidi injection when treating non-small cell lung cancer (NSCLC) patients is explained only by the effectiveness of a certain literature or the improvement of a certain evaluation index, and the result is not convincing. To evaluate the effect of Aidi injection on life quality and incidence of adverse reactions in patients with NSCLCcompared with traditional chemotherapy.

Methods

PubMed, EMBASE, ScienceDirect, Cochrane Library, China Journal full-text Database (CNKI), VIP full-text Database, Wanfang Database and Chinese Biomedical Literature data (CBM), search relevant Chinese and foreign periodicals, conference papers, degree papers, etc. were searched Database and China Biomedical Literature Database (CBM) to search case-control trials of Aidi injection when treating NSCLC patients. The retrieval period begins with the establishment of the database and ends when the database is closed. Cochrane Handbook 5.3 was adopted to assess the bias risk of each contained literature based on independently extracted data by two researchers. A meta-analysis of the collected data was carried out using RevMan5.3 statistical software.

Results

2306 articles were retrieved by computer database, 1422 articles were harvested by excluding repeated studies, 865 articles were harvested by preliminary reading of article titles and abstracts, and 533 articles were initially contained by excluding unrelated studies, reviews, case reports and uncontrolled articles, and then the full text of the literature was carefully read. Eight clinical controlled studies were finally included, with a total of 784 samples, after excluding 525 literatures with incomplete data and no primary outcome indicators. Data from the contained studies were not noticeably heterogeneous in the meta-analysis of treatment effectiveness. The fixed effect model analysis indicated that the treatment effective rate of the study group was noticeably better, and the difference was statistically significant(P<0.05). The findings of the heterogeneity test were clearly heterogeneous among the contained research data, according to the meta-analysis of the levels of T lymphocyte subsets following treatment. The random effect model analysis indicated that the improvement of the cellular immune function of the research group was obvious, and the difference was statistically significant (P<0.05). According to the meta-analysis of the life quality scores after treatment, data from the contained research were evidently heterogeneous, according to results of the heterogeneity test. The random effect model analysis indicated that the life quality of the study group was noticeably higher, and the difference was statistically significant (P<0.05). The levels of serum vascular endothelial growth factor (VEGF) after treatment were measured by meta. Data from the contained research were evidently heterogeneous, according to results of the heterogeneity test. Random effect model analysis indicated that the level of serum VEGF in the study group was noticeably lower, and the difference was not statistically significant (P>0.05). A meta-analysis was conducted on the incidence of adverse reactions after treatment. The results of the heterogeneity test indicated that data from the contained research were evidently heterogeneous. The incidence was noticeably lower, and the difference was statistically significant (P<0.05). The funnel chart was drawn based on the effective rate of treatment, the level of T lymphocyte subsets, the score of life quality, the level of serum VEGF and the incidence of adverse reactions, and the publication bias analysis was carried out. The results indicated that most of the funnel maps were symmetrical and a small part of them were asymmetrical, suggesting that despite the heterogeneity of the study and the small number of included literatures, a publication bias was apparent in the included literature.

Conclusion

Based on routine chemotherapy associated with Aidi injection, the therapeutic effect of NSCLC patients can be noticeably enhanced, the effective rate of treatment can be noticeably promoted, the immune function and life quality can be improved, and the incidence of adverse reactions is low, which is worth popularizing in clinical practice, but several studies and follow-ups are needed to improve methodological quality and to verify the results over a longer period of time.

Phase 2 Study of Osimertinib in Combination with Platinum and Pemetrexed in Patients with Previously Untreated EGFR-Mutated Advanced Non-Squamous Non-Small Cell Lung Cancer: The OPAL Study

BACKGROUND

This multicenter phase 2 trial evaluated the safety and efficacy of osimertinib and platinum-based chemotherapy (OPP) in patients with previously untreated EGFR-mutated advanced non-squamous non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Patients received osimertinib 80 mg once daily (QD), with either cisplatin 75 mg/m² (arm A) or carboplatin (area under the curve [AUC] = 5; arm B), plus pemetrexed 500 mg/m² for four cycles and maintenance therapy of osimertinib 80 mg QD with pemetrexed 500 mg/m² every 3 weeks. The primary end-points were safety and objective response rate (ORR), and the secondary end-points were complete response rate (CRR), disease control rate (DCR), and progression-free survival (PFS).

RESULTS

In total, 67 patients (34 in arm A and 33 in arm B) were enrolled between July 2019 and February 2020. At the data cutoff (28th February 2022), 35 (52.2%) patients had discontinued the protocol treatment, including 10 (14.9%) due to adverse events. No treatment-related deaths occurred. In the full analysis set, the ORR, CRR, and DCR were 90.9% (95% confidence interval [CI], 84.0-97.8), 3.0% (0.0-7.2), and 97.0% (92.8-100.0), respectively. Based on updated survival data (data cutoff on August 31, 2022, median follow-up time: 33.4 months), the median PFS was 31.0 months (95% CI, 26.8 months-not reached) and median overall survival was not reached.

CONCLUSIONS

This is the first study to show that OPP has excellent efficacy with acceptable toxicity in previously untreated EGFR-mutated advanced non-squamous NSCLC patients.

Hypoxic microenvironment in cancer: molecular mechanisms and therapeutic interventions

Having a hypoxic microenvironment is a common and salient feature of most solid tumors. Hypoxia has a profound effect on the biological behavior and malignant phenotype of cancer cells, mediates the effects of cancer chemotherapy, radiotherapy, and immunotherapy through complex mechanisms, and is closely associated with poor prognosis in various cancer patients. Accumulating studies have demonstrated that through normalization of the tumor vasculature, nanoparticle carriers and biocarriers can effectively increase the oxygen concentration in the tumor microenvironment, improve drug delivery and the efficacy of radiotherapy. They also increase infiltration of innate and adaptive anti-tumor immune cells to enhance the efficacy of immunotherapy. Furthermore, drugs targeting key genes associated with hypoxia, including hypoxia tracers, hypoxia-activated prodrugs, and drugs targeting hypoxia-inducible factors and downstream targets, can be used for visualization and quantitative analysis of tumor hypoxia and antitumor activity. However, the relationship between hypoxia and cancer is an area of research that requires further exploration. Here, we investigated the potential factors in the development of hypoxia in cancer, changes in signaling pathways that occur in cancer cells to adapt to hypoxic environments, the mechanisms of hypoxia-induced cancer immune tolerance, chemotherapeutic tolerance, and enhanced radiation tolerance, as well as the insights and applications of hypoxia in cancer therapy.

Carbonic Anhydrase IX Controls Vulnerability to Ferroptosis in Gefitinib-Resistant Lung Cancer

Acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI, such as gefitinib) in lung cancer continues to be a major problem. Recent studies have shown the promise of ferroptosis-inducing therapy in EGFR-TKI resistant cancer, but have not been translated into clinical benefits. Here, we identified carbonic anhydrase IX (CA9) was upregulated in gefitinib-resistant lung cancer. Then we measured the cell viability, intracellular reactive oxygen species (ROS) levels, and labile iron levels after the treatment of ferroptosis inducer erastin. We found that CA9 confers resistance to ferroptosis-inducing drugs. Mechanistically, CA9 is involved in the inhibition of transferrin endocytosis and the stabilization of ferritin, leading to resistance to ferroptosis. Targeting CA9 promotes iron uptake and release, thus triggering gefitinib-resistant cell ferroptosis. Notably, CA9 inhibitor enhances the ferroptosis-inducing effect of cisplatin on gefitinib-resistant cells, thus eliminating resistant cells in heterogeneous tumor tissues. Taken together, CA9-targeting therapy is a promising approach to improve the therapeutic effect of gefitinib-resistant lung cancer by inducing ferroptosis.

Molecular Mechanisms and Future Implications of VEGF/VEGFR in Cancer Therapy

Angiogenesis, the sprouting of new blood vessels from existing vessels, is one of six known mechanisms employed by solid tumors to recruit blood vessels necessary for their initiation, growth, and metastatic spread. The vascular network within the tumor facilitates the transport of nutrients, oxygen, and immune cells and is regulated by pro- and anti-angiogenic factors. Nearly four decades ago, VEGF was identified as a critical factor promoting vascular permeability and angiogenesis, followed by identification of VEGF family ligands and their receptors (VEGFR). Since then, over a dozen drugs targeting the VEGF/VEGFR pathway have been approved for approximately 20 solid tumor types, usually in combination with other therapies. Initially designed to starve tumors, these agents transiently "normalize" tumor vessels in preclinical and clinical studies, and in the clinic, increased tumor blood perfusion or oxygenation in response to these agents is associated with improved outcomes. Nevertheless, the survival benefit has been modest in most tumor types, and there are currently no biomarkers in routine clinical use for identifying which patients are most likely to benefit from treatment. However, the ability of these agents to reprogram the immunosuppressive tumor microenvironment into an immunostimulatory milieu has rekindled interest and has led to the FDA approval of seven different combinations of VEGF/VEGFR pathway inhibitors with immune checkpoint blockers for many solid tumors in the past 3 years. In this review, we discuss our understanding of the mechanisms of response and resistance to blocking VEGF/VEGFR, and potential strategies to develop more effective therapeutic approaches.

Dual-responsive nanoparticles loading bevacizumab and gefitinib for molecular targeted therapy against non-small cell lung cancer

The combination of vascular endothelial growth factor (VEGF) inhibitors and tyrosine kinase inhibitors (TKIs) is newly available for molecular targeted therapy against non-small cell lung cancer (NSCLC) in clinic. However, the therapeutic benefits remain unsatisfying due to the poor drug delivery to targets of interest. In this study, we developed bevacizumab-coated gefitinib-loaded nanoparticles (BCGN) with dual-responsive drug release for inhibiting tumor angiogenesis and phosphorylation of epidermal growth factor receptor (EGFR). Through an exogenous corona strategy, bevacizumab is easily coated on gefitinib-loaded nanoparticles via electrostatic interaction. After intravenous injection, BCGN are efficiently accumulated in NSCLC tumors as confirmed by dual-model imaging. Bevacizumab is released from BCGN upon oxidation in tumor microenvironment, whereas gefitinib is released after being internalized by tumor cells and disassembled in reduction cytoplasm. The dual-responsive release of bevacizumab and gefitinib significantly inhibits tumor growth in both A549 and HCC827 human NSCLC models. Our approach provides a promising strategy to improve combinational molecular targeted therapy of NSCLC with precisely controlled drug release.

EGFR-Tyrosine Kinase Inhibitors Induced Activation of the Autocrine CXCL10/CXCR3 Pathway through Crosstalk between the Tumor and the Microenvironment in EGFR-Mutant Lung Cancer

CXCL10 is a cytokine that is elevated during EGFR-TKI treatment in the tumor microenvironment of lung cancer. Here, we report an original study that the impact of the CXCL10/CXCR3 pathway on EGFR-TKI resistance in EGFR-mutant lung cancer through a cytokine array analysis during in vitro coculture with tumor cells and activated PBMCs treated with EGFR-TKI, as well as the serial analysis of CXCL10 in EGFR-mutant lung cancer transgenic mice during EGFR-TKI treatment. In EGFR-mutant tumor cells cocultured with activated PBMCs, EGFR-TKI treatment increased CXCL10 in the supernatant; this activated CXCR3 in the tumor cells to induce the phosphorylation of Src and the NF-κB subunit, p65, and the expression of HIF-1α. CXCL10 siRNA treatment of EGFR-mutant tumor cells also decreased CXCL10 in the supernatant from coculturing with activated PBMCs, suggesting that the effects of CXCL10 occur via autocrine and paracrine pathways. Importantly, elevated CXCL10/CXCR3 signaling was recapitulated in a transgenic lung cancer mouse model. Our results show that increased CXCL10 levels during early EGFR-TKI treatment stimulate oncogenic signaling of persistent tumor cells to contribute to EGFR-TKI resistance via autocrine and paracrine pathways.

Development and validation of a pyradiomics signature to predict initial treatment response and prognosis during transarterial chemoembolization in hepatocellular carcinoma

We aimed to develop and validate a pyradiomics model for preoperative prediction of initial treatment response to transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC). To this end, computed tomography (CT) images were acquired from multi-centers. Numerous pyradiomics features were extracted and machine learning approach was used to build a model for predicting initial response of TACE treatment. The predictive accuracy, overall survival (OS), and progression-free survival (PFS) were analyzed. Gene Set Enrichment Analysis (GSEA) was further used to explore signaling pathways in The Cancer Genome Atlas (TCGA)-HCC cohort. Overall, 24 of the 1,209 pyradiomic features were selected using the least absolute shrinkage and selection operator (LASSO) algorithm. The pyradiomics signature showed high predictive accuracy across the discovery set (AUC: 0.917, 95% confidence interval [CI]: 86.93-96.39), validation set 1 (AUC: 0.902, 95% CI: 84.81-95.59), and validation set 2 (AUC: 0.911; 95% CI: 83.26-98.98). Based on the classification of pyradiomics model, we found that a group with high values base on pyramidomics score showed good PFS and OS (both P<0.001) and was negatively correlated with glycolysis pathway. The proposed pyradiomics signature could accurately predict initial treatment response and prognosis, which may be helpful for clinicians to better screen patients who are likely to benefit from TACE.

Molecular basis and clinical implications of HIFs in cardiovascular diseases

Oxygen maintains the homeostasis of an organism in a delicate balance in different tissues and organs. Under hypoxic conditions, hypoxia-inducible factors (HIFs) are specific and dominant factors in the spatiotemporal regulation of oxygen homeostasis. As the most basic functional unit of the heart at the cellular level, the cardiomyocyte relies on oxygen and nutrients delivered by the microvasculature to keep the heart functioning properly. Under hypoxic stress, HIFs are involved in acute and chronic myocardial pathology because of their spatiotemporal specificity, thus granting them therapeutic potential. Most adult animals lack the ability to regenerate their myocardium entirely following injury, and complete regeneration has long been a goal of clinical treatment for heart failure. The precise manipulation of HIFs (considering their dynamic balance and transformation) and the development of HIF-targeted drugs is therefore an extremely attractive cardioprotective therapy for protecting against myocardial ischemic and hypoxic injury, avoiding myocardial remodeling and heart failure, and promoting recovery of cardiac function.

RELAY, ramucirumab plus erlotinib versus placebo plus erlotinib in untreated EGFR-mutated metastatic non-small cell lung cancer: exposure-response relationship

PURPOSE

In RELAY, ramucirumab plus erlotinib (RAM + ERL) improved progression-free survival (PFS) in patients with untreated, metastatic, EGFR-mutated, non-small cell lung cancer (NSCLC). Here, we present the exposure-response relationship of RAM from RELAY.

METHODS

Patients received ERL (150 mg/day) with either RAM (10 mg/kg) or placebo (PBO + ERL) every 2 weeks (Q2W). A population pharmacokinetic model predicted RAM minimum concentration after first dose (Cmin,1), and at steady state (Cmin,ss), which were used to evaluate correlation between RAM exposure and efficacy and safety. The Kaplan-Meier method and Cox regression analyses were utilized to evaluate exposure-efficacy by Cmin,1 quartile. Exposure-safety was evaluated by assessing incidence rates for safety parameters by Cmin,ss quartile, with ordered categorical analysis used for ALT/AST only.

RESULTS

Analyses included 216 patients treated with RAM + ERL and 225 patients treated with PBO + ERL. Adjusting for significant baseline covariates, no exposure-efficacy relationship was identified in RELAY: PFS hazard ratio (mean, 95% confidence intervals) for the Cmin,1 quartiles were 0.67 (0.45-0.99), 0.77 (0.53-1.12), 0.57 (0.38-0.84), and 0.50 (0.33-0.76). No apparent exposure-safety relationship was observed for selected safety endpoints, including Grade ≥ 3 hypertension, diarrhea, and dermatitis acneiform, and any grade hypertension, any grade and Grade ≥ 3 proteinuria, and any grade ALT/AST increased within liver failure/liver injury.

CONCLUSIONS

No association was observed between RAM exposure and response, suggesting that the RELAY regimen of RAM 10 mg/kg Q2W with ERL is an optimized, efficacious, and safe first-line treatment for patients with untreated, metastatic, EGFR-mutated NSCLC.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02411448.

Immunotherapy for EGFR-mutant advanced non-small-cell lung cancer: Current status, possible mechanisms and application prospects

Immune checkpoint inhibitors (ICIs) are effective against advanced and even perioperative non-small-cell lung cancer (NSCLC) and result in durable clinical benefit, regardless of programmed death ligand-1 (PD-L1) expression status in cancer. Existing clinical evidence shows that the effect of immunotherapy in patients with EGFR-mutant NSCLC after the development of tyrosine kinase inhibitor (TKI) resistance is not satisfactory. However, compared with monotherapy, ICIs combined with chemotherapy can improve the efficacy. Encouragingly, compared with that of patients with sensitive mutations, the progression-free survival of patients with rare mutations who were treated with ICIs was increased. Adequately maximizing the efficacy of ICIs in EGFR-mutant NSCLC patients is worth exploring. In this review, we described preclinical and clinical studies of ICIs or combined therapy for EGFR-mutant NSCLC. We further focused on EGFR mutations and the cancer immune response, with particular attention given to the role of EGFR activation in the cancer-immunity cycle. The mechanisms for the natural resistance to ICIs were explored to identify corresponding countermeasures that made more EGFR-mutant NSCLC patients benefit from ICIs.

Poziotinib for EGFR exon 20-mutant NSCLC: Clinical efficacy, resistance mechanisms, and impact of insertion location on drug sensitivity

We report a phase II study of 50 advanced non-small cell lung cancer (NSCLC) patients with point mutations or insertions in EGFR exon 20 treated with poziotinib (NCT03066206). The study achieved its primary endpoint, with confirmed objective response rates (ORRs) of 32% and 31% by investigator and blinded independent review, respectively, with a median progression-free survival of 5.5 months. Using preclinical studies, in silico modeling, and molecular dynamics simulations, we found that poziotinib sensitivity was highly dependent on the insertion location, with near-loop insertions (amino acids A767 to P772) being more sensitive than far-loop insertions, an observation confirmed clinically with ORRs of 46% and 0% observed in near versus far-loop, respectively (p = 0.0015). Putative mechanisms of acquired resistance included EGFR T790M, MET amplifications, and epithelial-to-mesenchymal transition (EMT). Our data demonstrate that poziotinib is active in EGFR exon 20-mutant NSCLC, although this activity is influenced by insertion location.

Effect of smoking habits on the efficacy of EGFR-TKI plus anti-angiogenic agent in advanced EGFR-mutant NSCLC

BACKGROUND

The types of epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) patients who could obtain significant clinical benefit from the dual inhibition of EGFR/vascular EGFR (VEGFR) pathways remain unclear. No consensus has been reached on the significance of smoking habits in clinical benefit obtained from EGFR-TKI plus anti-angiogenic agents.

METHODS

PubMed, EMBASE, and Cochrane databases for all phase II/III randomized clinical trials (RCTs) investigating the efficacy of EGFR-TKI combined with anti-angiogenic agents stratified by smoking habits (updated October 2021) were searched systematically. The primary outcomes were the pooled HRs for PFS/OS in smokers and non-smokers, and differences in efficacy of EGFR-TKI plus anti-angiogenic treatment between smokers and non-smokers, measured by difference in PFS and OS.

RESULTS

Seven phase II/III RCTs involving 1452 patients were identified. The pooled analysis demonstrated that EGFR-TKI plus anti-angiogenic agent could decrease the risk of progression by 40% (HR, 0.60; 95%CI 0.48-0.75) in smokers when compared with EGFR-TKI alone, but not in non-smokers (HR, 0.92; 95%CI 0.68-1.25). The comparison analysis further demonstrated that EGFR-mutated NSCLC patients who smoked obtained greater progression-free survival (PFS) benefit from treatment with EGFR-TKI plus anti-angiogenic agents (HR, 0.68; 95%CI 0.51-0.91). Consistent with the results for PFS, smokers receiving EGFR-TKI plus anti-angiogenic agents appeared to exhibit better overall survival (OS) than non-smokers but not to a statistically significant degree (HR, 0.60; 95%CI 0.23-1.52). Meta-regression analysis revealed no significant effect of the line of treatment (P = 0.52), trial phase (P = 0.52), EGFR-TKI type (P = 0.13), or anti-angiogenic agent type (P = 0.50) on PFS effect sizes under multivariate models.

CONCLUSION

Comprehensive analysis suggested that EGFR-TKI plus anti-angiogenic agents led to favorable PFS among smoking EGFR-mutant patients, comparable to nonsmokers, which might provide a useful guide for clinicians.

LncRNA USP2-AS1 Promotes Hepatocellular Carcinoma Growth by Enhancing YBX1-Mediated HIF1α Protein Translation Under Hypoxia

Recently, the role of lncRNAs in tumorigenesis and development has received increasing attention, but the mechanism underlying lncRNAs-mediated tumor growth in the hypoxic microenvironment of solid tumors remains obscure. Using RNA sequencing, 25 hypoxia-related lncRNAs were found to be upregulated in HCC, of which lncRNA USP2-AS1 were significantly increased under hypoxia. We further confirmed that USP2-AS1 was significantly upregulated in liver cancer using FISH assay and that USP2-AS1 was associated with advanced liver cancer and increased tumor size. Furthermore, overexpression of USP2-AS1 under hypoxia dramatically increased HCC proliferation and clone formation, whereas the opposite results were observed after USP2-AS1 knockdown. We also found that overexpression of USP2-AS1 increased migration and invasion of HCC cells, while USP2-AS1 knockdown led to the opposite effect. In addition, USP2-AS1 knockdown can increase the efficacy of lenvatinib in our mice tumor xenograft model. Our findings also suggest that USP2-AS1 could increase the protein level of HIF1α by enhancing YBX1 protein binding to HIF1α mRNA under hypoxia and the therapeutic effect of lenvatinib can be enhanced by combination with HIF1α inhibitors in liver cancer.

Sequence-dependent synergistic effect of aumolertinib-pemetrexed combined therapy on EGFR-mutant non-small-cell lung carcinoma with pre-clinical and clinical evidence

BACKGROUND

Inevitably developed resistance of the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) limited its clinical benefit on non-small cell lung cancer (NSCLC). Upfront combination therapy is promising to prevent this resistance. Compelling clinical evidence indicated the failure of third-generation EGFR TKIs combined with either immunotherapy or antiangiogenic agents. In comparison, combined treatment of third-generation EGFR TKIs and chemotherapy might be a favorable choice. Herein, we systematically analyzed and compared the effects of pemetrexed and a novel third-generation EGFR TKI aumolertinib combined in different sequences, subsequently revealed the potential mechanisms and proved the optimal combination schedule with clinical retrospective study.

METHODS

Three combination schedules involving pemetrexed and aumolertinib in different sequences were developed. Their inhibition effects on cell proliferation and metastasis were firstly compared upon three human NSCLC cell lines in vitro, by cell counting kit-8, colony formation, wound healing and transwell assays respectively. Further evaluation in vivo was proceeded upon H1975 and HCC827 xenograft model. Gene and protein expression were detected by Q-PCR and western blot. Drug concentration was determined by LC-MS/MS. VEGF secretion was determined by ELISA. Tumor vessel was visualized by immunofluorescence. Lastly, a clinical retrospective study was raised with 65 patients' data.

RESULTS

The combination of pemetrexed and aumolertinib exhibited a sequence-dependent and EGFR mutant-dependent synergistic effect in vitro and in vivo. Only treatment with aumolertinib following pemetrexed (P-A) exhibited synergistic effect with stronger anti-tumor growth and anti-metastasis ability than monotherapy and also other combination sequences. This synergism could exclusively be observed in H1975 and HCC827 but not A549. Pathway analysis showed that P-A significantly enhanced the suppression of EGFR pathway. In addition, our results intriguingly found an obvious reduction of VEGF secretion and the accompanying normalization of the intratumor vessel, consequently increasing intratumoral accumulation of pemetrexed in P-A group. Finally, the clinical retrospective study verified the synergistic effect of P-A combination by significantly superior tumor response than aumolertinib monotherapy.

CONCLUSION

Aumolertinib-pemetrexed combined therapy is promising for EGFR mutant NSCLC but only in right administration sequence. P-A could become an advantageous combination strategy in clinical with synergistic inhibition of tumor growth and metastasis.

Anti-angiogenesis revisited: reshaping the treatment landscape of advanced non-small cell lung cancer

Although anti-angiogenic agents have been of limited use in the treatment of non-small cell lung cancer (NSCLC) until recently, further roles for the use of angiogenesis inhibition have emerged in the era of targeted therapy and immune checkpoint blockade. Given the shared common downstream signals of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) with their complementary roles in tumorigenesis and tumor angiogenesis, the dual inhibition of EGFR and VEGF pathways represents a rational strategy to maximize clinical efficacy and overcome resistance in the treatment of EGFR-mutant NSCLC. VEGF-driven angiogenesis is a potent driver of immunosuppressive tumor microenvironment (TME), with the recruited immunosuppressive cells driving angiogenesis, highlighting the interplay between the tumor vasculature and the anticancer immunity. Anti-angiogenic therapy can normalize the tumor vasculature and reprogram the TME from immunosuppressive into immunosupportive. Intensive research is under way to utilize the anti-angiogenic combination therapy to its full potential in diverse clinical settings in urgent unmet needs for the treatment of NSCLC. In this review, we present an overview of tumor angiogenesis and summarize the scientific background and preclinical and clinical evidence of anti-angiogenic therapy in combination with target therapy and immunotherapy for the treatment of NSCLC.

EGFR signaling pathway as therapeutic target in human cancers

Epidermal Growth Factor Receptor (EGFR) enacts major roles in the maintenance of epithelial tissues. However, when EGFR signaling is altered, it becomes the grand orchestrator of epithelial transformation, and hence one of the most world-wide studied tyrosine kinase receptors involved in neoplasia, in several tissues. In the last decades, EGFR-targeted therapies shaped the new era of precision-oncology. Despite major advances, the dream of converting solid tumors into a chronic disease is still unfulfilled, and long-term remission eludes us. Studies investigating the function of this protein in solid malignancies have revealed numerous ways how tumor cells dysregulate EGFR function. Starting from preclinical models (cell lines, organoids, murine models) and validating in clinical specimens, EGFR-related oncogenic pathways, mechanisms of resistance, and novel avenues to inhibit tumor growth and metastatic spread enriching the therapeutic portfolios, were identified. Focusing on non-small cell lung cancer (NSCLC), where EGFR mutations are major players in the adenocarcinoma subtype, we will go over the most relevant discoveries that led us to understand EGFR and beyond, and highlight how they revolutionized cancer treatment by expanding the therapeutic arsenal at our disposal.

Current status of immunotherapy for non-small cell lung cancer

Nowadays, lung cancer is still the deadliest oncological disease in the world. Among them, non-small cell lung cancer (NSCLC) accounts for 80%∼85% of all lung cancers, and its 5-year survival rate is less than 15%, making the situation critical. In the past decades, despite some clinical advances in conventional treatments, the overall survival rate of NSCLC is still not optimistic due to its unique physiological conditions and the frequent occurrence of tumor escape. In recent years, immunotherapy has become a new hot spot in lung cancer research, including antibody therapy and cell therapy, which have been developed and utilized one after another, especially immune checkpoint inhibitor (ICI). These approaches have effectively improved the overall survival rate and objective response rate of NSCLC patients by enhancing the immune capacity of the body and targeting tumor cells more effectively, which is more specific and less toxic compared with conventional chemotherapy, and providing more strategies for NSCLC treatment. In this paper, we reviewed the relevant targets, clinical progress and adverse reaction in monoclonal antibodies, antibody-drug conjugates, ICI, bispecific antibodies, T-cell receptor engineered T cell therapy (TCR-T), Chimeric antigen receptor T-cell immunotherapy (CAR-T), and also report on their combination therapy from the immune-related background to provide better NSCLC treatment and prospective.

Case Report: Osimertinib Followed by Osimertinib Plus Bevacizumab, Personalized Treatment Strategy for a Lung Cancer Patient With a Novel EGFR Exon 20 Insertion D770_N771insGT and Multiple Brain Metastases

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs) are the standard of care for non–small cell lung cancer (NSCLC) patients with EGFR exon 19 deletion and L858R mutations. However, no EGFR TKI has been approved for NSCLC patients harboring insertion mutations in EGFR exon 20 (EGFRex20ins), a subgroup of uncommon EGFR mutations resistant to first-generation EGFR TKIs. This unmet clinical challenge is further complicated by disease progression due to brain metastases (BMs), which limits the use of EGFR TKIs with low intracranial activity. Osimertinib, a third-generation EGFR TKI with high CNS activity, has demonstrated superior efficacy as a first-line treatment for EGFR-mutant NSCLC with or without BM. The VEGF pathway is a key mediator of cancer metastasis and resistance to EGFR TKIs. Accumulating evidence has demonstrated that the addition of anti-VEGF agents to EGFR TKIs provides an alternative treatment option for the clinical management of EGFR-mutant NSCLC. We herein report an NSCLC case with a novel EGFRex20ins mutation D770_N771insGT and multiple brain metastases who briefly responded to first-line osimertinib treatment and subsequently achieved prolonged disease control with osimertinib plus bevacizumab as second-line treatment. Our case suggests that osimertinib in combination with bevacizumab may be an effective option for NSCLC patients with specific EGFRex20ins mutations and brain metastases.

The safety and efficacy of erlotinib and ramucirumab combination in EGFR-mutant non-small-cell lung cancer

INTRODUCTION

EGFR-tyrosine kinase inhibitors (TKIs) changed the natural history of EGFR-mutant advanced NSCLC patients, but acquired resistance is inevitable. New strategies are being tested to overcome or prevent the emergence of resistance mechanisms to first-line TKIs, among which combinations of TKIs with antiangiogenic agents.

AREAS COVERED

We performed a literature search for preclinical and clinical data on the interplay and dual inhibition of EGFR/VEGF pathways, particularly in EGFR-mutant NSCLC. We then focused on RELAY, a placebo-controlled phase 3 trial evaluating ramucirumab combined to erlotinib in treatment-naïve advanced EGFR-mutant NSCLC patients. This article aims to summarize efficacy and safety of the ramucirumab-erlotinib combination in this setting.

EXPERT OPINION

RELAY confirmed the clinical relevance of combining EGFR and VEGF(R)-targeting therapies, previously investigated in smaller phase 2-3 trials of erlotinib and bevacizumab. However, the meaningful PFS benefit observed in the ramucirumab + erlotinib arm is counterbalanced by the toxicity profile of ramucirumab and the need for bimonthly infusions. Pending OS results are, therefore, critical to assess the real benefit from this combination, especially as first-line osimertinib has improved survival in EGFR-mutant NSCLC patients and will probably remain the pivotal EGFR-TKI in this setting. However, its heterogeneous efficacy across subgroups paves the way for osimertinib-based combinations, which are being investigated in ongoing trials.

DCE-MRI quantitative transport mapping for noninvasively detecting hypoxia inducible factor-1α, epidermal growth factor receptor overexpression, and Ki-67 in nasopharyngeal carcinoma patients

BACKGROUND

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has the potential to noninvasively detect expression of hypoxia inducible factor-1-alpha (HIF-1α), epidermal growth factor receptor (EGFR), and Ki-67 in nasopharyngeal carcinoma (NPC) by quantitatively measuring tumor blood flow, vascularity, and permeability.

PURPOSE

We aim to explore the utility of DCE-MRI in detecting HIF-1α, EGFR, and Ki-67 expression levels using traditional Kety's/Tofts' modeling and quantitative transport mapping (QTM).

MATERIALS AND METHODS

Eighty-nine NPC patients underwent DCE-MRI before treatment were enrolled. DCE-MRI was processed to generate the following kinetic parameters: |u| and D from the QTM model, tumor blood flow (TBF) from Kety's model, and K^trans, V_e, and K_ep from Tofts' model. Pretreatment levels of HIF-1α, EGFR, and Ki-67 were assessed by immunohistochemistry and classified into low and high expression groups.

RESULTS

|u| (p < 0.001) and TBF (p = 0.015) values were significantly higher in the HIF-1α high-expression group compared to low-expression group. Only K^trans (p = 0.016) was significantly higher in the EGFR high-expression group. Only |u| (p < 0.001) values were significantly higher in the Ki-67 high-expression group compared to low-expression group. Multiple linear regression analyses showed that |u| independently correlated with HIF-1α and Ki-67 expression, and K^trans independently correlated with EGFR. The areas under the ROC curves of |u| for HIF-1α and Ki-67, and K^trans for EGFR were 0.83, 0.74, and 0.70, respectively.

CONCLUSION

|u| and K^trans derived from DCE-MRI may be considered as noninvasive imaging markers for detecting hypoxia and proliferation in NPC patients.

The role of ramucirumab with docetaxel in epidermal growth factor receptor mutant and wild-type non-small cell lung cancer

Background

Ramucirumab paired with docetaxel extends progression free survival and overall survival in non-small cell lung cancer (NSCLC) following progression on platinum therapy. There is some data that epidermal growth factor receptor (EGFR) mutant disease would respond better to vascular endothelial growth factor receptor (VEGFR) therapy than EGFR wild type disease.

Methods

This retrospective, single-institution cohort study reports outcomes of patients who received docetaxel with or without ramucirumab according to EGFR status. Clinical data including age, performance status, metastatic burden and prior treatment history was obtained and reported with time on treatment and overall survival as primary endpoints. Data analysis was performed for three cohorts: EGFR mutant disease receiving docetaxel and ramucirumab (EGFR-doce/ram), EGFR mutant disease receiving docetaxel alone (EGFR-doce) and EGFR wild type disease receiving docetaxel and ramucirumab (WT-doce/ram).

Results

Patients in the EGFR-doce/ram cohort had a median time on docetaxel of 1.4 months (95% CI: 0.72-5.2 months) and of 0.8 months (95% CI: 0.2-6.5 months) on ramucirumab. Patients in the EGFR-doce cohort were on docetaxel for a median 1.4 months (95% CI: 0.9-2.4 months). Patients in the WT-doce/ram cohort had a median time on docetaxel of 2.3 months (95% CI: 1.6-4.1 months) and on ramucirumab of 1.4 months (95% CI: 0.8-3.2 months). There was no significant difference between time on ramucirumab or docetaxel between the cohorts. Overall survival for the three cohorts was noted to be 6.7 months (95% CI: 2.5-16.2 months) for the EGFR-doce/ram cohort, 4.9 months (95% CI: 4.2-12.5 months) for the EGFR-doce cohort and 6.6 months (95% CI: 4.3-12.8 months) for the WT-doce/ram cohort. There was no significant difference in overall survival between the cohorts.

Conclusions

Our data did not support the initial hypothesis that patients with EGFR mutant disease would do better with the addition of ramucirumab. Our study was limited by small sample size, retrospective nature and inability to control for confounders including prior bevacizumab or immune checkpoint inhibitor (ICI) exposure. This study offers real-world estimates to clinicians and patients about the length of time they can expect to derive benefit from the combination of ramucirumab and docetaxel.

ARTEMIS highlights VEGF inhibitors as effective partners for EGFR TKIs in EGFR mutant NSCLC

The randomized ARTEMIS study demonstrates that adding the VEGF inhibitor bevacizumab to the EGFR inhibitor erlotinib improves progression-free survival in EGFR mutant non-small-cell lung cancer by more than 6 months, with even greater benefits seen in patients with brain metastases and EGFR L858R mutation. This provides further evidence for the tailored use of VEGF/EGFR combinations.

SIRT1/PGC-1α/PPAR-γ Correlate With Hypoxia-Induced Chemoresistance in Non-Small Cell Lung Cancer

Resistance is the major cause of treatment failure and disease progression in non-small cell lung cancer (NSCLC). There is evidence that hypoxia is a key microenvironmental stress associated with resistance to cisplatin, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), and immunotherapy in solid NSCLCs. Numerous studies have contributed to delineating the mechanisms underlying drug resistance in NSCLC; nevertheless, the mechanisms involved in the resistance associated with hypoxia-induced molecular metabolic adaptations in the microenvironment of NSCLC remain unclear. Studies have highlighted the importance of posttranslational regulation of molecular mediators in the control of mitochondrial function in response to hypoxia-induced metabolic adaptations. Hypoxia can upregulate the expression of sirtuin 1 (SIRT1) in a hypoxia-inducible factor (HIF)-dependent manner. SIRT1 is a stress-dependent metabolic sensor that can deacetylate some key transcriptional factors in both metabolism dependent and independent metabolic pathways such as HIF-1α, peroxisome proliferator-activated receptor gamma (PPAR-γ), and PPAR-gamma coactivator 1-alpha (PGC-1α) to affect mitochondrial function and biogenesis, which has a role in hypoxia-induced chemoresistance in NSCLC. Moreover, SIRT1 and HIF-1α can regulate both innate and adaptive immune responses through metabolism-dependent and -independent ways. The objective of this review is to delineate a possible SIRT1/PGC-1α/PPAR-γ signaling-related molecular metabolic mechanism underlying hypoxia-induced chemotherapy resistance in the NSCLC microenvironment. Targeting hypoxia-related metabolic adaptation may be an attractive therapeutic strategy for overcoming chemoresistance in NSCLC.

Apatinib Plus Gefitinib as First-Line Treatment in Advanced EGFR-Mutant NSCLC: The Phase III ACTIVE Study (CTONG1706)

INTRODUCTION

Blocking vascular endothelial growth factor pathway can enhance the efficacy of EGFR tyrosine kinase inhibitors in EGFR-mutant NSCLC. ACTIVE is the first phase 3 study conducted in the People's Republic of China evaluating apatinib, a vascular endothelial growth factor receptor 2 tyrosine kinase inhibitor, plus gefitinib as first-line therapy in EGFR-mutant NSCLC.

METHODS

Treatment-naive patients with stage IIIB or IV nonsquamous NSCLC, an Eastern Cooperative Oncology Group performance status of 0 or 1, and EGFR exon 19 deletion or exon 21 L858R mutation were randomized 1:1 to receive oral gefitinib (250 mg/d), plus apatinib (500 mg/d; apatinib [A] + gefitinib [G] group), or placebo (placebo [P] + gefitinib [G] group). Stratification factors were mutation type, sex, and performance status. The primary end point was progression-free survival (PFS) by blinded independent radiology review committee (IRRC). Secondary end points were investigator-assessed PFS, overall survival, quality of life (QoL), safety, etc. Next-generation sequencing was used to explore efficacy predictors and acquired resistance.

RESULTS

A total of 313 patients were assigned to the A + G (n = 157) or P + G group (n = 156). Median IRRC PFS in the A + G group was 13.7 months versus 10.2 months in the P + G group (hazard ratio 0.71, p = 0.0189). Investigator- and IRRC-assessed PFS were similar. Overall survival was immature. The most common treatment-emergent adverse events greater than or equal to grade 3 were hypertension (46.5%) and proteinuria (17.8%) in the A + G group and increased alanine aminotransferase (10.4%) and aspartate aminotransferase (3.2%) in the P + G group. QoL in the two groups had no statistical differences. Post hoc analysis revealed PFS benefits tended to favor the A + G group in patients with TP53 exon 8 mutation.

CONCLUSIONS

Apatinib + gefitinib as first-line therapy had superior PFS in advanced EGFR-mutant NSCLC versus placebo + gefitinib. Combination therapy brought more adverse events but did not interfere QoL.

TRIAL REGISTRATION

NCT02824458.