Anlotinib can overcome acquired resistance to EGFR-TKIs via FGFR1 signaling in non-small cell lung cancer without harboring EGFR T790M mutation

Liensinine overcomes EGFR-TKI resistance in lung adenocarcinoma through DRP1-mediated autophagy

INTRODUCTION

Persistent upregulation of autophagy contributes to tumour cells' resistance to EGFR-TKI therapy, and hence, inhibiting autophagy could be a valuable strategy for overcoming such resistance.

OBJECTIVES

This study investigated the effects of liensinine in EGFR-TKI resistant lung adenocarcinoma (LUAD) and to explore the underlying mechanism.

METHODS

CCK-8 assay, colony formation, EdU assay and apoptosis assays were conducted for investigating the effect of EGFR-TKI and liensinine combination treatment in LUAD. Furthermore, autophagic flux were detected by western blot, fluorescence assays and TEM. In addition, by employing a DARTS approach, a CETSA assay, and SPR analysis, we identified DRP1 as a target of liensinine. Finally, by establishing a xenograft model of the disease, the impact of combination treatment in vivo was assessed.

RESULT

In vitro and in vivo experiments revealed that the novel autophagy inhibitor liensinine enhanced the sensitivity of LUAD to EGFR-TKIs. This effect was achieved by inhibiting autophagic flux. We then examined whether liensinine inhibits autophagic flux through the impairment of autophagosome and autolysosome degradation. Furthermore, we identified DRP1 as a target of liensinine. The activation of DRP1 by liensinine through dephosphorylation at Ser637 promotes the accumulation of autophagosomes and autolysosomes while simultaneously blocking autophagic flux, thereby enhancing the cancer cell-killing effects of EGFR-TKIs.

CONCLUSIONS

Our study validated the efficacy of liensinine in overcoming EGFR-TKI resistance and elucidated the mechanism underlying liensinine's inhibition of autophagy.

Anlotinib enhances the anti-tumor activity of osimertinib in patients with non-small cell lung cancer by reversing drug resistance

Background

Osimertinib, a third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), significantly improves the prognosis of patients with EGFR-mutant non-small cell lung cancer (NSCLC). However, subsequently-acquired resistance limits its effectiveness. This study aimed to explore the efficacy of anlotinib, a multitarget inhibitor of angiogenesis, in combination with osimertinib using in vitro and in vivo EGFR-TKI-sensitive and EGFR-TKI-resistant models.

Methods

We established osimertinib-resistant cell lines (H1975-OR and PC9-OR) and evaluated the effects of osimertinib, anlotinib, and their combination on cell proliferation in vivo and in vitro. In addition, we used pleural fluid from nine patients with EGFR-mutant NSCLC who received osimertinib therapy in the clinic to successfully establish a zebrafish patient-derived xenograft (zPDX) model. The effect of the combined treatment in vivo was assessed by quantifying red fluorescent regions representing tumor cell growth in zebrafish embryos to assess tumor proliferation and migration.

Results

Combination osimertinib and anlotinib therapy did not have an obvious synergistic antiproliferative effect in parental H1975 and PC9 cells; however, anlotinib reversed osimertinib resistance in osimertinib-resistant H1975-OR and PC9-OR cells in vivo and in vitro. A similar phenomenon was observed in the zPDX model.

Conclusions

In conclusion, anlotinib did not significantly enhance the anti-tumor effects of osimertinib in osimertinib-sensitive NSCLC cell lines or a zPDX model. However, it partially reversed osimertinib resistance. This combination therapy may improve the outcomes of patients with advanced NSCLC showing osimertinib-resistance.

Pharmacological and Biological Targeting of FGFR1 in Cancer

FGFR1 is a key member of the fibroblast growth factor receptor family, mediating critical signaling pathways such as RAS-MAPK and PI3K-AKT. which are integral to regulating essential cellular processes, including proliferation, differentiation, and survival. Alterations in FGFR1 can lead to constitutive activation of signaling pathways that drive oncogenesis by promoting uncontrolled cell division, inhibiting apoptosis, and enhancing the metastatic potential of cancer cells. This article reviews the activation mechanisms and signaling pathways of FGFR1 and provides a detailed exposition of the types of FGFR1 aberration. Furthermore, we have compiled a comprehensive overview of current therapies targeting FGFR1 aberration in cancer, aiming to offer new perspectives for future cancer treatments by focusing on drugs that address specific FGFR1 alterations.

The later-line efficacy and safety of immune checkpoint inhibitors plus anlotinib in EGFR-mutant patients with EGFR-TKI-resistant NSCLC: a single-center retrospective study

BACKGROUND

Effective treatment after EGFR-TKI resistance is of great clinical concern. We aimed to investigate the efficacy and safety of anlotinib in combination with an anti-PD-1/PD-L1 antibody in later-line therapy for EGFR-mutant NSCLC patients after TKI treatment failure and to explore the independent predictive factors of therapeutic efficacy.

METHODS

A total of 71 patients with confirmed advanced EGFR-mutated NSCLC who progressed after previous standard EGFR-TKI therapy but still failed after multiline treatments were included retrospectively in this study. Most of the patients had previously received at least three lines of treatment. All were treated with anlotinib combined with anti-PD-1 or anti-PD-L1 therapy. The safety of this combined treatment was assessed by the incidence of adverse events. The efficacy of the regimens was evaluated by survival analysis (OS, PFS, ORR, DCR).

RESULTS

The median follow-up period was 28.6 months (range: 2.3-54.0 months), and the median number of treatment lines was 4. The overall response rate (ORR) and disease control rate (DCR) were 19.7% and 77.5%, respectively. The median PFS was 5.8 months (95% CI 4.2-7.4 months), and the median OS was 17.1 months (95% CI 12.0-22.3 months). Patients who received immune checkpoint inhibitors plus anlotinib had an encouraging intracranial ORR of 38.5% and a DCR of 80.8%. ECOG performance status < 2 at baseline was independent protective factors of PFS. Metastatic organs and ECOG performance status were independent parameters in predicting OS. Treatment-related adverse events occurred in 66 (93.0%) patients; most of the adverse events were Grade 1-2, and no increase in adverse events was observed compared to monotherapy.

CONCLUSION

Anlotinib combined with an anti-PD-1/PD-L1-based regimen exhibited promising efficacy and tolerance in NSCLC patients with EGFR mutations after previous TKI failure. The efficacy of this combined regimen in patients with EGFR mutations should be further evaluated.

Synergistic anticancer effects of ginsenoside CK and gefitinib against gefitinib-resistant NSCLC by regulating the balance of angiogenic factors through HIF-1α/VEGF

Drug resistance is a serious problem for gefitinib in the treatment of lung cancer. Ginsenoside CK, a metabolite of diol ginsenosides, have many excellent pharmacological activities, but whether ginsenoside CK can overcome gefitinib resistance remains unclear. In our study, the sensitizing activity of ginsenoside CK on gefitinib-resistant non-small cell lung cancer (NSCLC) in vitro and in vivo was investigated. Ginsenoside CK was confirmed to enhance the anti-proliferation, pro-apoptotic and anti-migration effects of gefitinib in primary and acquired resistant NSCLC. Furthermore, the combined administration of CK and gefitinib effectively promoted the sensitivity of lung cancer xenograft to gefitinib in vivo, and the tumor inhibition rate reached 70.97% (vs. gefitinib monotherapy 32.65%). Subsequently, tubule formation experiment and western blot results showed that co-treatment of ginsenoside CK inhibited the angiogenesis ability of HUVEC cells, and inhibited the expression of HIF-1α, VEGF, FGF and MMP2/9. More interestingly, ginsenoside CK co-treatment enhanced the expression of anti-angiogenic factor PF4, increased pericellular envelope, and promoted the normalization of vascular structure. In conclusion, ginsenoside CK improved the resistance of gefitinib by regulating the balance of angiogenic factors through down-regulating the HIF-1α/VEGF signaling pathway, providing a theoretical basis for improving the clinical efficacy of gefitinib and applying combined strategies to overcome drug resistance.

SOD2 confers anlotinib resistance via regulation of mitochondrial damage in OSCC

OBJECTIVE

Previous studies had revealed that anlotinib had outstanding anti-tumor efficacy on oral squamous cell carcinoma. However, the underlying mechanism is still unclear.

MATERIALS AND METHODS

Anlotinib resistant OSCC cells were established and analyzed by RNA-sequencing. The correlations between SOD2 expression and anlotinib resistance were investigated in OSCC cells and PDX models. Functional assays were performed to verify the SOD2 expression and anlotinib resistance in OSCC cells.

RESULTS

Anlotinib resistant genes were enriched in the biological processes of mitochondrion organization and the gene pathway of reactive oxygen species. SOD2 expression level was positively correlated with the resistance of anlotinib in OSCC cells and PDX models. Higher SOD2 expression of OSCC cells was more resistant to anlotinib. Anlotinib induced ROS generation, apoptosis and mitochondrial damage in OSCC cells, which can be enhanced by SOD2 knockdown and decreased by SOD2 overexpression. Mitochondrial damage was identified as swelling and cristae disappearance morphology under TEM, decreased mitochondrial membrane potential and lower MFN2 expression.

CONCLUSIONS

SOD2 may be capable of protecting mitochondria by downregulating ROS generation, which contributes to the resistance of anlotinib in OSCC cells. SOD2 can be utilized as a potential therapeutic target to improve the anti-cancer efficacy of anlotinib in OSCC.

Efficacy and Safety of Anlotinib-Containing Regimens in Advanced Non-Small Cell Lung Cancer: A Real-World Study

Purpose

Anlotinib is widely used in the clinical treatment of non-small cell lung cancer (NSCLC), alone or in combination with other anticancer drugs. The aim of this study was to investigate the real-world efficacy and safety of anlotinib-containing regimens.

Patients and Methods

Confirmed advanced NSCLC patients who had received anlotinib alone or in combination were enrolled. An overall analysis of the efficacy and safety of anlotinib was performed in all patients, and then subgroup analysis was used to further compare the efficacy between anlotinib monotherapy and combination therapy. The primary endpoint was progression-free survival (PFS), and the secondary endpoints were ADR, ORR, and DCR.

Results

A total of 240 patients were included. The overall median PFS was 8.5 months (95% confidence interval [CI]: 7.1-9.9 months). Anlotinib treatment regimens (monotherapy or combination therapy) and whether they received previous antiangiogenesis were associated with PFS. Anlotinib plus immunotherapy achieved longer PFS than anlotinib monotherapy (median PFS: 10.5 vs 6.5 months, p=0.007). Stratification analysis showed the PFS of anlotinib plus immunotherapy was significantly longer in male, adenocarcinoma, <=65 years old, patients stage IV, EGFR wild type, with extrathoracic metastasis, performance status scores ≥2, the first-line treatment, patients with a history of hypertension and no previous antiangiogenesis than anlotinib monotherapy. The median PFS of anlotinib plus chemotherapy, targeted therapy was slightly longer than anlotinib alone (respectively, 10.5 vs 6.5 months, p=0.095; 9.5 vs 6.5 months, p=0.177). Adverse reactions were mostly mild and acceptable, with hypertension being the most common.

Conclusion

Anlotinib is effective and tolerable in advanced NSCLC patients. Immunotherapy combination with anlotinib significantly improved PFS. The efficacy of anlotinib may be impaired by previous antiangiogenic therapy, which can be investigated in further studies.

Low‑dose anlotinib combined with EGFR‑TKI can be used as an alternative for EGFR‑TKI‑resistant non‑small cell lung cancer in elderly patients

The current treatment options for epidermal growth factor receptor (EGFR) mutation-positive lung cancer in the elderly with tyrosine kinase inhibitor (TKI) resistance are limited. Although chemotherapy combined with vascular endothelial growth factor inhibitors significantly improves progression-free survival (PFS) in TKI-resistant patients, it often cannot be tolerated in elderly patients, leading to treatment failure. Anlotinib is a small molecule inhibitor made in China. The application of low-dose anlotinib in elderly patients with TKI-resistant lung cancer deserves further investigation. A total of 48 elderly patients with non-small cell lung cancer (NSCLC) were enrolled to evaluate the efficacy of anlotinib combined with continuous EGFR-TKI vs. anlotinib monotherapy in patients with acquired EGFR-TKI resistance. Anlotinib was administered at a dose of 6-8 mg per day, lower than the normal dose and known as a low dose, which is well tolerated in elderly patients. There were 25 cases in the combination group and 23 cases in the anlotinib monotherapy group. The primary endpoint of the present study was PFS, and the secondary endpoints were overall survival (OS), response rate and toxicity. The median PFS (mPFS) was significantly longer in the combination group than that in the anlotinib monotherapy group: 6.0 months [95% confidence interval (CI), 4.35-7.65] compared with 4.0 months (95% CI, 3.38-4.62) (P=0.002). Analysis of the subgroups showed similar trends in results. The median OS was 32 months (95% CI, 22.04-41.96) in the combination group and 28 months (95% CI, 27.13-28.87) in the anlotinib monotherapy group (P=0.217). According to stratification analysis, second-line treatment with anlotinib combined with EGFR-TKI resulted in a better mPFS than third-line treatment (7.5 vs. 3.7 months, HR=3.477; 95% CI, 1.117-10.820; P=0.031). In the combination group, patients with gradual/local progression after EGFR-TKI failure had a longer mPFS than those with dramatic progression (7.5 vs. 6.0 months, HR=5.875; 95% CI, 1.414-10.460; P=0.015). Multivariate analyses showed that continuous EGFR-TKI combined with anlotinib after EGFR-TKI resistance was associated with longer PFS (P=0.019), whereas dramatic progression (P=0.014) had a detrimental effect on follow-up treatment. Grade 2 adverse events (AEs) were reported in four patients (17.39%) in the anlotinib monotherapy group and eight patients (32.00%) in the combination group. Of these, the most common grade 2 AEs were hypertension, fatigue, diarrhea, paronychia, mucositis and transaminase elevation. There were no grade 3/4/5 AEs. In conclusion, the present study demonstrated that low-dose anlotinib combined with EGFR-TKI is superior to anlotinib alone following EGFR-TKI failure, making it the preferred regimen for elderly patients with acquired EGFR-TKI resistance.

Experimental study of EGFR-TKI aumolertinib combined with ionizing radiation in EGFR mutated NSCLC brain metastases tumor

Aumolertinib is an irreversible third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), although it has been administered for the treatment of epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC). However, it is unclear whether aumolertinib combined with ionizing radiation (IR) has potential therapeutic effects in treating brain metastases (BM) tumors from NSCLC. This study explored the anti-tumor effects of aumolertinib combined with IR in epidermal growth factor receptor mutated (EGFRm) NSCLC BM tumors. First, we established a xenograft model of NSCLC BM tumors in BALB/c nude mice and assessed the anti-tumor effects of this combination. Furthermore, we examined the concentrations of aumolertinib in brain tissue and blood using liquid chromatography-mass spectrometry (LC-MS); after that, we used CCK-8, colony formation, flow cytometry assay, and immunofluorescence staining to detect the effects of aumolertinib combined with IR upon PC-9 and NCI-H1975 cells, such as cell proliferation, survival, apoptosis, cycle distribution, the situation of DNA damage, and the expression levels of relevant proteins which were detected via western blotting; finally, we chose a clinical case with which to explore the clinical benefits to the EGFRm NSCLC BM patient after the treatment of the aforementioned combination. The experiments of NSCLC BM tumor animal models demonstrated that the combination enhanced the therapeutic effects and increased the intracranial accumulation of aumolertinib; the combination can inhibit cell proliferation and survival, delay the repair of DNA damage, and increase the rates of cell apoptosis and aumolertinib abrogated G2/M phase arrest, which the IR induced; the clinical study verified that the combination demonstrated better patient benefits. In conclusion, our study demonstrated that combining aumolertinib and IR has promising anti-tumor effects in EGFR-mutant NSCLC and that this combined treatment modality may be employed as a potential therapeutic strategy for EGFR-mutant NSCLC BM patients clinically.

Anlotinib plus chemotherapy for T790M-negative EGFR-mutant non-sqNSCLC resistant to TKIs: A multicenter phase 1b/2 trial

BACKGROUND

This multicenter phase 1b/2 trial aimed to explore the maximum tolerated dose (MTD), activity, and safety of anlotinib plus chemotherapy in patients with T790M-negative epidermal growth factor receptor (EGFR)-mutant advanced nonsquamous non-small cell lung cancer (NSCLC) after resistance to first- or second-generation EGFR tyrosine kinase inhibitors (TKIs).

METHODS

In the phase 1b stage, patients received anlotinib (8/10/12 mg, days 1-14) combined with cisplatin (75 mg/m² , day 1) or carboplatin (AUC = 5, day 1) plus pemetrexed (500 mg/m² , day 1) for a 3-week cycle based on a 3 + 3 dose-escalation design. In the phase 2 single-arm stage, anlotinib was administered at MTD combined with platinum plus pemetrexed for four cycles, followed by anlotinib maintenance therapy. The primary endpoint of the phase 2 stage was progression-free survival (PFS).

RESULTS

The study was prematurely terminated due to slow accrual after 19 patients had been enrolled between January 18, 2019, and March 21, 2021. The MTD of anlotinib was 12 mg. The median PFS was 5.75 (95% confidence interval, 4.37-7.52) months. The objective response rate was 47.4% (95% confidence interval, 24.5%-71.1%). In the 12 mg group, seven (58.3%) patients experienced grade 3-4 treatment-related adverse events, and the most common ones were hypertension (6 [50.0%]), decreased platelet count (2 [16.7%]), and hypertriglyceridemia (1 [8.3%]). No treatment-related deaths occurred.

CONCLUSION

Anlotinib plus platinum and pemetrexed showed promising antitumor activity with manageable toxicity in patients with T790M-negative EGFR-mutant advanced nonsquamous NSCLC after progression on first- or second-generation EGFR TKIs.

Efficacy and potential resistance mechanisms of afatinib in advanced non-small cell lung cancer patients with EGFR G719X/L861Q/S768I

BACKGROUND

Afatinib is the only currently approved EGFR-tyrosine kinase inhibitors for advanced non-small cell lung cancer (NSCLC) patients with EGFR G719X/L861Q/S768I. However, there are limited real-world data concerning the benefits and resistance mechanisms of afatinib in patients with these nonclassical mutations. To fill this gap, the present study was conducted.

METHODS

All NSCLC patients treated with afatinib were screened, and patients with EGFR G719X/L861Q/S768I were enrolled into the analysis. Either tumor tissue or blood specimens were detected by the commercial next-generation sequencing (NGS) panels or amplification-refractory mutation system (ARMS)-polymerase chain reaction (PCR) to figure out the mutation genotype.

RESULTS

A total of 106 advanced NSCLC patients with EGFR G719X/L861Q/S768I received afatinib treatment. The benefits of afatinib exhibited heterogeneity in different mutation genotypes. Notably, at baseline, NGS testing was performed in 59 patients, and TP53 was the most frequently coexisting mutation. Patients with TP53 mutations obtained fewer survival benefits than those with TP53 wild-type. A total of 68 patients ultimately experienced progression, and 27 patients received NGS testing to clarify the potential resistance mechanisms. EGFR-T790M, CDK4 amplification, FGFR1 amplification, PIK3CA, MET amplification, RET fusions, HER2, and BRAF mutations were identified in three (11.1%), three (11.1%), three (11.1%), three (11.1%), three (11.1%), one (3.7%), one (3.7%), and one (3.7%) of the cases, respectively. Five patients underwent ARMS-PCR testing for detecting EGFR-T790M mutation, and only one patient was T790M-positive.

CONCLUSIONS

The present study elucidated the differential benefits of afatinib within different mutation genotypes and first revealed the spectrum of potential resistance mechanisms in patients with EGFR G719X/L861Q/S768I. The results of this study may provide practical clinical information that can guide optimal treatment in this setting.

Exosomal miR-181a-3p Regulates the Anlotinib Resistance of Lung Cancer Cells

This study investigates the mechanism of Anlotinib in the treatment of lung cancer drug resistance. A total of 30 lung cancer tissue specimens were retrospectively analyzed and 30 normal lung tissues were included as a control. Real-time PCR detected miR-181a-3p expression along with analysis of cell viability by MTT assay, cell invasion by transwell, and the exosomal miR-181a-3p/UPR/ERAD signaling pathway. The expression of miR-181a-3p in peripheral blood of lung cancer was increased and the overall survival rate of patients with high miR-181a-3p in exosomes was shorter than patients with low expression. In A549 and H292 cell lines, anlotinib is added to overexpress exosomal miR-181a-3p, cell viability and invasion were significantly increased. After knocking down exosomal miR-181a-3p, cell viability and invasion were significantly reduced. The expression of miR-181a-3p is directly regulated by exosomes UPR/ERAD. After overexpression of exosomes miR-181a-3p, the protein levels of UPR and ERAD were significantly reduced and increased after knockdown of exosomes miR-181a-3p. In conclusion, the secretory miR-181a-3p/UPR/ERAD pathway promotes the proliferation of A549 and H292 cells, regulates the resistance of Anlotinib, and can increase the resistance of lung cancer to Anlotinib by promoting the proliferation signaling pathway, and promote the growth of tumor cells.

New developments in the biology of fibroblast growth factors

The fibroblast growth factor (FGF) family is composed of 18 secreted signaling proteins consisting of canonical FGFs and endocrine FGFs that activate four receptor tyrosine kinases (FGFRs 1-4) and four intracellular proteins (intracellular FGFs or iFGFs) that primarily function to regulate the activity of voltage-gated sodium channels and other molecules. The canonical FGFs, endocrine FGFs, and iFGFs have been reviewed extensively by us and others. In this review, we briefly summarize past reviews and then focus on new developments in the FGF field since our last review in 2015. Some of the highlights in the past 6 years include the use of optogenetic tools, viral vectors, and inducible transgenes to experimentally modulate FGF signaling, the clinical use of small molecule FGFR inhibitors, an expanded understanding of endocrine FGF signaling, functions for FGF signaling in stem cell pluripotency and differentiation, roles for FGF signaling in tissue homeostasis and regeneration, a continuing elaboration of mechanisms of FGF signaling in development, and an expanding appreciation of roles for FGF signaling in neuropsychiatric diseases. This article is categorized under: Cardiovascular Diseases > Molecular and Cellular Physiology Neurological Diseases > Molecular and Cellular Physiology Congenital Diseases > Stem Cells and Development Cancer > Stem Cells and Development.

A Linear Discriminant Analysis Model Based on the Changes of 7 Proteins in Plasma Predicts Response to Anlotinib Therapy in Advanced Non-Small Cell Lung Cancer Patients

Background

Anlotinib is a multi-targeted tyrosine kinase inhibitor mainly targeting angiogenesis signaling. The predictive marker of anlotinib’s efficacy remains elusive. This study was designed to explore the predictive marker of anlotinib in non-small cell lung cancer (NSCLC).

Methods

We prospectively enrolled 52 advanced NSCLC patients who underwent at least one line of targeted therapy or chemotherapy between August 2018 and March 2020. Patients were divided into durable responders (DR) and non-durable responders (NDR) based on the median progression-free survival (PFS, 176 days). The Olink Immuno-Oncology panel (92 proteins) was used to explore the predictive protein biomarkers in plasma samples before treatment (baseline) and on the first treatment evaluation (paired).

Results

At baseline, the response to anlotinib was not significantly associated with age, gender, smoke history, histology, oligo-metastases, EGFR mutations, and other clinical characteristics. The results of PFS-related protein biomarkers at baseline were all not satisfying. Then we assessed the changes of 92 proteins levels in plasma on the first treatment evaluation. We obtained a Linear discriminant analysis (LDA) model based on 7 proteins, with an accuracy of 100% in the original data and an accuracy of 89.2% in cross validation. The 7 proteins were CD70, MIC-A/B, LAG3, CAIX, PDCD1, MMP12, and PD-L2. Multivariate Cox analysis further showed that the changes of CD70 (HR 25.48; 95% CI, 4.90–132.41, P=0.000) and MIC-A/B (HR 15.04; 95% CI, 3.81–59.36, P=0.000) in plasma were the most significant prognostic factors for PFS.

Conclusion

We reported herein a LDA model based on the changes of 7 proteins levels in plasma before and after treatment, which could predict anlotinib responders among advanced NSCLC patients with an accuracy of 100%. Further studies are warranted to verify the prediction performance of the LDA model.

Metformin Potentiates the Effects of Anlotinib in NSCLC via AMPK/mTOR and ROS-Mediated Signaling Pathways

Anlotinib is a novel multi-targeted tyrosine kinase inhibitor with activity against soft tissue sarcoma, small cell lung cancer, and non-small cell lung cancer (NSCLC). Potentiating the anticancer effect of anlotinib in combination strategies remains a clinical challenge. Metformin is an oral agent that is used as a first-line therapy for type 2 diabetes. Interesting, metformin also exerts broad anticancer effects through the activation of AMP-activated protein kinase (AMPK) and inhibition of mammalian target of rapamycin (mTOR). Here, we evaluated the possible synergistic effect of anlotinib and metformin in NSCLC cells. The results showed that metformin enhanced the antiproliferative effect of anlotinib. Moreover, anlotinib combined with metformin induced apoptosis and oxidative stress, which was associated with the activation of AMPK and inhibition of mTOR. Reactive oxygen species (ROS)- mediated p38/JNK MAPK and ERK signaling may be involved in the anticancer effects of this combination treatment. Our results show that metformin potentiates the efficacy of anlotinib in vivo by increasing the sensitivity of NSCLC cells to the drug. These data provide a potential rationale for the combination of anlotinib and metformin for the treatment of patients with NSCLC or other cancers.

Real-World Efficacy and Safety of Anlotinib With and Without Immunotherapy in Advanced Non-Small Cell Lung Cancer

Aims

Combination of anti-angiogenesis therapy and immunotherapy has showed synergistic effects in non-small cell lung cancer (NSCLC). The aim of this retrospective study was to investigate the efficacy and safety of anlotinib with and without immunotherapy in NSCLC.

Methods

Pathologically confirmed NSCLC patients (stage IIIB-IV) receiving anlotinib between November 2018 and February 2020 were enrolled for retrospective analysis. The outcomes and safety of overall patients were evaluated, and the efficacies of anlotinib plus immunotherapy and anlotinib alone was compared. The primary endpoint was progression-free survival (PFS).

Results

A total of 80 patients (median age: 62 years, range: 29-86 years) were included. Overall median PFS was 4.3 months (95% confidence interval (CI): 2.7-5.9 months). In univariate analysis, patients without EGFR mutation, previous EGFR target therapy, and brain metastasis had significantly longer PFS. Cox regression analysis showed that only brain metastasis was an independent predictor of PFS. The median PFS of patients receiving anlotinib plus immunotherapy was slightly longer than that of patients receiving anlotinib alone (4.2 vs 3.1 months); however, the difference was not statistically significant. A tendency of longer median PFS was observed in patients with adenocarcinoma, EGFR wild type, stage IV, no liver metastasis, former smoker, ≥2 previous treatment lines, no previous VEGF or EGFR target therapies in anlotinib plus immunotherapy group. Treatments with anlotinib alone or anlotinib plus immunotherapy were well tolerable. The most common adverse events were fatigue, decreased hemoglobin count, hypertension, hand-foot syndrome, oral mucositis and hoarseness.

Conclusion

Anlotinib is well tolerable and effective in advanced NSCLC patients. Brain metastasis is an independent predictor of PFS in NSCLC patients receiving anlotinib. Future prospective studies with larger sample size and extended follow-up are needed to confirm the clinical benefit in NSCLC patients treated with anlotinib combined with immunotherapy.

Abnormally activated OPN/integrin αVβ3/FAK signalling is responsible for EGFR-TKI resistance in EGFR mutant non-small-cell lung cancer

BACKGROUND

Acquired epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance limits the long-term clinical efficacy of tyrosine kinase-targeting drugs. Although most of the mechanisms of acquired EGFR-TKI resistance have been revealed, the mechanism of ~ 15% of cases has not yet been elucidated.

METHODS

Cell viability was analysed using the Cell Counting Kit-8 (CCK-8) assay. Proteome profiler array analysis was performed to find proteins contributing to acquired EGFR-TKI resistance. Secreted OPN was detected by ELISA. Immunohistochemical analysis was conducted to detect expression of integrin αV in NSCLC tissue. The effect of VS-6063 on apoptosis and proliferation of PC9 gefitinib-resistant cells was detected by fluorescence-activated cell sorting (FACS) and clonogenic assays. A mouse xenograft model was used to assess the effect of VS-6063 on the sensitivity of PC9 gefitinib-resistant cells to gefitinib.

RESULTS

OPN was overexpressed in acquired EGFR-TKI-resistant NSCLCs. Secreted OPN contributed to acquired EGFR-TKI resistance by activating the integrin αVβ3/FAK pathway. Inhibition of FAK signalling increased sensitivity to EGFR-TKIs in PC9 gefitinib-resistant cells both in vitro and in vivo.

CONCLUSIONS

OPN contributes to acquired EGFR-TKI resistance by up-regulating expression of integrin αVβ3, which activates the downstream FAK/AKT and ERK signalling pathways to promote cell proliferation in NSCLC.

Targeting c-kit inhibits gefitinib resistant NSCLC cell growth and invasion through attenuations of stemness, EMT and acquired resistance

EGFR tyrosine kinase inhibitors (TKIs) are the first-line drugs for NSCLC. But, the acquired resistance limited their efficacy, so that the patients deteriorate eventually. Therefore, it is necessary to clarify the mechanism of the acquired resistance and overcome it for effective NSCLC therapy. In this experimental study, a stable gefitinib resistant lung adenocarcinoma cell line (PC9/GR) infected with shRNA-c-kit-homo-1386 were established; c-kit siRNA and c-kit inhibitors were used to block c-kit signaling; the acquired resistance of PC9/GR cells and the effects of c-kit siRNA and c-kit inhibitors on the growth and invasion of PC9/GR cells were investigated with CCK-8 assay, colony formation and cell invasion assays in vitro; the tumor growth inhibition effects of c-kit inhibitors on PC9/GR cell generated tumors were tested in vivo; the mechanisms involved in the acquired resistance reverse, growth and invasion inhibition effects of c-kit siRNA and c-kit inhibitors on PC9/GR cells were evaluated with qRT-PCR, Western blot and immunohistochemistry staining. The proliferation, colony formation, and invasion of PC9/GR cells were decreased by c-kit siRNA and inhibitors in vitro significantly; c-kit inhibitors suppressed the tumor growth of PC9/GR cell generated tumors in vivo. In the stable shRNA-c-kit transfected PC9/GR cells, the protein expressions of c-kit signaling and stemness phenotype related proteins, including ALDH1A1, Oct4, Sox2 and ABCG2 were decreased, and EMT phenotype related protein expressions including vimentin, N-cadherin, and Slug, were downregulated and with upregulation of E-cadherin; c-kit inhibitors reduced stemness phenotype related protein expressions, downregulated EMT phenotype related protein expressions including vimentin, N-cadherin, and Slug, with upregulation of E-cadherin, and the stemness related protein expressions of c-kit, ALDH1A1, ABCG2 and EMT-related proteins of vimentin and slug were decreased in the imatinib treated tumor tissues. The findings of this study indicated that c-kit signaling mediated the acquired gefitinib resistance, cell growth, invasion, stemness and EMT phenotype of PC9/GR cells. Targeting c-kit signaling with c-kit siRNA and small molecule c-kit inhibitors might overcome the acquired gefitinib resistance, and inhibit PC9/GR cell growth in vitro and in vivo.