Treatment of Non-small Cell Lung Cancer with EGFR-mutations

Anlotinib combined with gefitinib can significantly improve the proliferation of epidermal growth factor receptor-mutant advanced non-small cell lung cancer in vitro and in vivo

Background

The effect of anlotinib combined with epidermal growth factor receptor TKIs (EGFR-TKIs) in patients with advanced non-small cell lung cancer (NSCLC) with acquired resistance to EGFR-TKIs and the possible molecular mechanisms are still unclear.

Methods

From April 2018 to June 2020, 20 patients with advanced NSCLC who had developed potential acquired drug resistance after receiving gefitinib or icotinib were enrolled. Anlotinib (12 mg orally, once a day) was added to the targeted drug at the original dose. Patients underwent computed tomography every 8 weeks, and the curative effect and related side effects were observed. Furthermore, in vitro experiments were performed to study the effect of anlotinib alone or in combination with gefitinib on the proliferation and clone-forming ability of NSCLC cells (A549 cells: EGFR wild-type; H1975 cells: with L858R and T790M mutations). Immunohistochemistry was used to detect the expression of related proteins (Ki-67, CD31, EGFR, P-EGFR, VEGFR2, and p-VEGFR2).

Results

After the administration of anlotinib, 8 patients were in a stable condition and continued to receive treatment, and the best efficacy disease control rate (DCR) was 100%. The median follow-up time was 6.6 months (4.08-8.28 months). The median progression-free survival was 15.7 months (10.19-18.87 months). The levels of the tumor marker (carcinoembryonic antigen) were found to be significantly decreased in seven patients. The main adverse reactions reported after anlotinib administration were hypertension, hand-foot-skin reaction, diarrhea, fatigue, oral ulcers, and anorexia.In the in vitro experiment, anlotinib combined with gefitinib significantly inhibited the proliferation and cloning ability of lung cancer cells. In the nude mouse model, this combination treatment significantly inhibited the growth of lung cancer cells. Immunohistochemical results showed that anlotinib combined with gefitinib significantly inhibited the expression of Ki-67, CD31, EGFR, P-EGFR, VEGFR2, and p-VEGFR2 in tumor tissues.

Conclusions

Anlotinib combined with gefitinib inhibited the proliferation of EGFR-TKI-resistant NSCLC cells in vitro and tumor angiogenesis in vivo. It also significantly improved the treatment efficacy for some patients, delaying disease progression and improving survival, with only mild side effects. This drug combination is therefore a promising treatment for patients with EGFR-TKI-resistant and potentially secondary drug-resistant advanced NSCLC.

Longitudinal Change of Circulating Tumor Cells During Chemoradiation and Its Correlation with Prognosis in Advanced Nonsmall-Cell Lung Cancer Patients

Background: This study aimed to investigate the association of circulating tumor cells (CTCs) change during chemoradiation with the treatment response and survival profiles in advanced nonsmall-cell lung cancer (NSCLC) patients. Materials and Methods: Fifty-eight advanced NSCLC patients who underwent concurrent chemoradiation were enrolled, then their peripheral blood samples were collected before chemoradiation, and at 1 month postchemoradiation assessed the CTCs using a CTC-Biopsy system. Moreover, CTCs were classified as CTCs positive and CTCs negative according to CTCs' count, and change of CTCs was calculated. In addition, response of chemoradiation was evaluated at 1 month postchemoradiation, then progression-free survival (PFS) and overall survival (OS) were assessed. Results: Prechemoradiation CTCs positive were associated with increased TNM stage, but not other clinicopathologic characteristics. After chemoradiation, the CTCs' number [1.0 (0.0-3.0) vs. 4.0 (2.0-10.0)] and the percentage of CTC-positive cases (37.9% vs. 77.6%) were both decreased compared to those before chemoradiation. Regarding treatment response, prechemoradiation CTCs positive were associated with lower partial response; postchemoradiation CTCs positive were associated with reduced disease control rate, while CTCs' change during chemoradiation was not associated with treatment response. Kaplan-Meier curves showed that postchemoradiation CTCs positive and increased CTCs' number during chemoradiation were associated with reduced PFS, then multivariate Cox's regression analysis disclosed that they independently predicted decreased PFS. However, no correlation of CTCs' status or CTCs' change with OS was observed. Conclusions: Prechemoradiation CTCs relate to increased TNM stage and worse prognosis in chemoradiation-treated advanced NSCLC patients.

Downregulation of breast cancer resistance protein by long-term fractionated radiotherapy sensitizes lung adenocarcinoma to SN-38

Chemotherapy is usually the subsequent treatment for non-small cell lung cancer patients with acquired radioresistance after long-term fractionated radiotherapy. However, few studies have focused on the selection of chemotherapeutic drugs to treat lung adenocarcinoma patients with radioresistance. Our study compared the sensitivity changes of lung adenocarcinoma cells to conventional chemotherapeutic drugs under radioresistant circumstances by using three lung adenocarcinoma cell models, which were irradiated with fractionated X-rays at a total dose of 60 Gy. The results showed that the toxicities of paclitaxel, docetaxel and SN-38 were increased in radioresistant cells. The IC₅₀ values of docetaxel and SN-38 decreased 0 ~ 3 times and 3 ~ 36 times in radioresistant cells, respectively. Notably, the A549 radioresistant cells were approximately 36 times more sensitive to SN-38 than the parental cells. Further results revealed that the downregulation of the efflux transporter BCRP by long-term fractionated irradiation was an important factor contributing to the increased cytotoxicity of SN-38. In addition, the reported miRNAs and transcriptional factors that regulate BCRP did not participate in the downregulation. In conclusion, these results presented important data on the sensitivity changes of lung adenocarcinoma cells to chemotherapeutic drugs after acquiring radioresistance and suggested that irinotecan (the prodrug of SN-38) might be a promising drug candidate for lung adenocarcinoma patients with acquired radioresistance.

Organ-restricted vascular delivery of nanoparticles for lung cancer therapy

Nanoparticle-based targeted drug delivery holds promise for treatment of cancers. However, most approaches fail to be translated into clinical success due to ineffective tumor targeting in vivo. Here, the delivery potential of mesoporous silica nanoparticles (MSN) functionalized with targeting ligands for EGFR and CCR2 is explored in lung tumors. The addition of active targeting ligands on MSNs enhances their uptake in vitro but fails to promote specific delivery to tumors in vivo, when administered systemically via the blood or locally to the lung into immunocompetent murine lung cancer models. Ineffective tumor targeting is due to efficient clearance of the MSNs by the phagocytic cells of the liver, spleen, and lung. These limitations, however, are successfully overcome using a novel organ-restricted vascular delivery (ORVD) approach. ORVD in isolated and perfused mouse lungs of Kras-mutant mice enables effective nanoparticle extravasation from the tumor vasculature into the core of solid lung tumors. In this study, ORVD promotes tumor cell-specific uptake of nanoparticles at cellular resolution independent of their functionalization with targeting ligands. Organ-restricted vascular delivery thus opens new avenues for optimized nanoparticles for lung cancer therapy and may have broad applications for other vascularized tumor types.

Promoter Methylation of Selected Genes in Non-Small-Cell Lung Cancer Patients and Cell Lines

Specific gene promoter DNA methylation is becoming a powerful epigenetic biomarker in cancer diagnostics. Five genes (CDH1, CDKN2Ap16, RASSF1A, TERT, and WT1) were selected based on their frequently published potential as epigenetic markers. Diagnostic promoter methylation assays were generated based on bisulfite-converted DNA pyrosequencing. The methylation patterns of 144 non-small-cell lung cancer (NSCLC) and 7 healthy control formalin-fixed paraffin-embedded (FFPE) samples were analyzed to evaluate the applicability of the putative diagnostic markers. Statistically significant changes in methylation levels are shown for TERT and WT1. Furthermore, 12 NSCLC and two benign lung cell lines were characterized for promoter methylation. The in vitro tests involved a comparison of promoter methylation in 2D and 3D cultures, as well as therapeutic tests investigating the impact of CDH1/CDKN2Ap16/RASSF1A/TERT/WT1 promoter methylation on sensitivity to tyrosine kinase inhibitor (TKI) and DNA methyl-transferase inhibitor (DNMTI) treatments. We conclude that the selected markers have potential and putative impacts as diagnostic or even predictive marker genes, although a closer examination of the resulting protein expression and pathway regulation is needed.

Synergistic effects of Bcl-2 inhibitors with AZD9291 on overcoming the acquired resistance of AZD9291 in H1975 cells

Non-small cell lung cancer (NSCLC) patients with epithermal growth factor receptor (EGFR) mutations can be treated with EGFR-tyrosine kinase inhibitors (EGFR-TKIs), however, development of acquired resistance could significantly limit curative effects of EGFR-TKIs. Different mechanisms of acquired resistance to first-generation and second-generation EGFR TKIs have been widely reported, but there were few reports on the resistant mechanism of third-generation EGFR-TKI such as osimertinib (AZD9291). In the present study, significant upregulation of Bcl-2 was found in AZD9291-resistant H1975 cells (H1975AR) compared with H1975, which may constitute an important resistant mechanism of acquired resistance to AZD9291. More importantly, our study showed that synergism between AZD9291 and Bcl-2 inhibitor ABT263 (0.25 μM) or ABT199 (1 μM) could effectively overcome the acquired resistance of AZD9291 in H1975AR in vitro. Flow cytometry analyses demonstrated that AZD9291 + ABT263/ABT199 caused a significantly different cell cycle distribution and produced significantly more apoptosis compared with either AZD9291 or ABT263/ABT199 treatment alone. Further multiscreen/Western blot analyses revealed that NF-κB was significantly downregulated in AZD9291 + ABT263/ABT199 treatment groups compared with AZD9291 or ABT263/ABT199 treatment alone, with a more significant reduction of NF-κB in AZD9291 + ABT199 compared with AZD9291 + ABT263. It is also noticeable that AZD9291 + ABT263 specifically caused a significantly reduced expression of p21 compared with AZD9291 or ABT263 treatment alone while AZD9291 + ABT199 specifically caused significantly reduced expressions of SQSTM1 and survivin, but increased expression of autophagosome marker LC3-II compared with AZD9291 or ABT199 treatment alone. Furthermore, cytotoxicity of AZD9291 + ABT199 could be partially reversed by autophagy inhibitor chloroquine. These results suggest that ABT263 and ABT199 may work through different signaling pathways to achieve synergistic cytotoxicity with AZD9291 in H1975AR. These findings suggest that Bcl-2 inhibitor may provide an effective option in combination therapy with EGFR-TKIs to treat NSCLC with EGFR-TKI acquired resistance.

A review of Osimertinib in NSCLC and pharmacist role in NSCLC patient care

Lung cancer is a complex, genetically heterogeneous disease. It is the most common cause of cancer-related deaths worldwide. Non-small cell lung cancer (NSCLC) represents the majority of the diagnosed lung cancer cases. Osimertinib is a new treatment option that demonstrated a superior efficacy over standard epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) or platinum-based chemotherapy. The safety and efficacy of osimertinib (a third generation EGFR-TKIs) were confirmed by well-designed clinical trials. Consequently, osimertinib was considered a first-line treatment option, particularly in patients with EGFR mutant NSCLC. It has been approved by FDA for the treatment of advance or metastatic NSCLC patients with specific EGFR-mutant NSCLC. As an active member of the multidisciplinary team, pharmacist has a promising role in assuring safe, effective and cost-effective treatment in patient with NSCLC. This review article aims to highlight the latest evidence about osimertinib use as a new treatment option in the clinical practice and to review the potential pharmacist key roles in NSCLC patient care.