Drug resistance analysis of gefitinib-targeted therapy in non-small cell lung cancer

Rhein Inhibits the Progression of Chemoresistant Lung Cancer Cell Lines via the Stat3/Snail/MMP2/MMP9 Pathway

Chemotherapy is a common drug for lung cancer. Nevertheless, the development of drug resistance greatly limits their clinical efficacy. Therefore, to reduce drug resistance, we need to constantly explore new treatments. This study is aimed at determining the role of rhein in the proliferation and metastasis of lung cancer cell. Our study found that rhein significantly inhibits the proliferation and migration of lung cancer cells. Additionally, the mRNA expression and protein levels of Snail, MMP2, and MMP9 are decreasing in lung cancer cells treated by rhein. Our results showed that rhein plays a vital role in proliferation and metastasis of chemosensitive and chemoresistant lung cancer cells, and the mechanism may be related to the Stat3/Snail/MMP2/MMP9 pathway.

Physicochemical Characterization and Biopharmaceutical Evaluation of ZWF: A Novel Anticancer Drug for the Treatment of Non-small Cell Lung Cancer

The orally available novel small molecule drug ZWF is under preclinical development for an anticancer purpose. The present study aimed to assess the viability of developing ZWF as a form of oral formulation for clinical application based on the principles of biopharmaceutics and pharmacokinetics. The crucial physicochemical properties of ZWF were determined by in vitro assays. The in situ gastrointestinal absorption characteristics and in vivo pharmacokinetic behaviors of ZWF in rats were characterized. The solubility of ZWF showed a highly pH-dependent profile, decreasing from 25,392.89 to 20.48 μg/mL as the solution pH increased from 1.0 to 5.8. In PBS with a pH of 1.0 to 5.8, the LogP value of ZWF ranged from -2.35 to 2.20 and was gradually increased as the pH value increased. ZWF was partially absorbed in the stomach, and the favorable absorption sites were the duodenum, jejunum, and ileum. Pharmacokinetic studies showed that the AUC_(0-t) and C_max values of ZWF after its oral administration as a suspension prepared with 0.5% CMC-Na were increased by 18.97% and 40% than that with normal saline, providing a model oral formulation of ZWF with ideal bioavailability and system exposure in rats. From the perspective of oral absorption, ZWF possessed appealing qualities as a drug candidate and could be prepared as an oral preparation for clinical application. The present study has established a fundamental foundation for the development and quality evaluation of the ZWF oral formulations.

SOX9 promotes epidermal growth factor receptor-tyrosine kinase inhibitor resistance via targeting β-catenin and epithelial to mesenchymal transition in lung cancer

AIMS

The first-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), gefitinib, continues to be a primary treatment option for lung cancer patients. However, acquisition of resistance to gefitinib is a major obstacle in lung cancer treatment and its cause is poorly understood. The present study aimed to implicate the role of SOX9-β-catenin in developed resistance to gefitinib through epithelial to mesenchymal transition (EMT) in lung cancer in vitro and ex vivo.

MAIN METHODS

Expression effect of SOX9 on survivability of lung cancer patients was demonstrated through online available Kaplan-Meier Plotter data base. Then, cell viability assay, colony forming assay, cell migration and invasion assays, flow cytometry, drug efflux assay, qRT-PCR, and western blotting were conducted to confirmed the role of SOX9 in gefitinib resistance in lung cancer cells. Dual-luciferase assay established the regulatory relation between SOX9 and β-catenin. Multicellular spheroid assay further explored that down regulation of SOX9 could reverse gefitinib resistance ex vivo.

KEY FINDINGS

Kaplan-Meier method correlated the higher expression of SOX9 and β-catenin with poor overall survival of lung cancer patients. Upregulation of SOX9 was associated gefitinib resistance with increased cell proliferation, migration and invasion, single-cell colony-forming ability, reduced apoptosis, and gefitinib intake in lung cancer cells. Moreover, upregulated SOX9 promoted EMT via targeting β-catenin and knockdown of SOX9 reversed the resistance and EMT phenotype. Similarly, we found that multicellular spheroid of gefitinib resistant cells showed larger surface area with more dispersion and viability of cells, while SOX9 knockdown abolished these induced properties ex vivo.

SIGNIFICANCE

SOX9 expression could provide an innovative perspective as biomarker to understand the EGFR-TKIs resistance in lung cancer.

Targeting Hypoxia Sensitizes TNBC to Cisplatin and Promotes Inhibition of Both Bulk and Cancer Stem Cells

Development of targeted therapies for triple-negative breast cancer (TNBC) is an unmet medical need. Cisplatin has demonstrated its promising potential for the treatment of TNBC in clinical trials; however, cisplatin treatment is associated with hypoxia that, in turn, promotes cancer stem cell (CSC) enrichment and drug resistance. Therapeutic approaches to attenuate this may lead to increased cisplatin efficacy in the clinic for the treatment of TNBC. In this report we analyzed clinical datasets of TNBC and found that TNBC patients possessed higher levels of EGFR and hypoxia gene expression. A similar expression pattern was also observed in cisplatin-resistant ovarian cancer cells. We, thus, developed a new therapeutic approach to inhibit EGFR and hypoxia by combination treatment with metformin and gefitinib that sensitized TNBC cells to cisplatin and led to the inhibition of both CD44+/CD24− and ALDH+ CSCs. We demonstrated a similar inhibition efficacy on organotypic cultures of TNBC patient samples ex vivo. Since these drugs have already been used frequently in the clinic; this study illustrates a novel, clinically translatable therapeutic approach to treat patients with TNBC.

Precision medicine in gastric cancer

Gastric cancer (GC) is a complex disease linked to a series of environmental factors and unhealthy lifestyle habits, and especially to genetic alterations. GC represents the second leading cause of cancer-related deaths worldwide. Its onset is subtle, and the majority of patients are diagnosed once the cancer is already advanced. In recent years, there have been innovations in the management of advanced GC including the introduction of new classifications based on its molecular characteristics. Thanks to new technologies such as next-generation sequencing and microarray, the Cancer Genome Atlas and Asian Cancer Research Group classifications have also paved the way for precision medicine in GC, making it possible to integrate diagnostic and therapeutic methods. Among the objectives of the subdivision of GC into subtypes is to select patients in whom molecular targeted drugs can achieve the best results; many lines of research have been initiated to this end. After phase III clinical trials, trastuzumab, anti-Erb-B2 receptor tyrosine kinase 2 (commonly known as ERBB2) and ramucirumab, anti-vascular endothelial growth factor receptor 2 (commonly known as VEGFR2) monoclonal antibodies, were approved and introduced into first- and second-line therapies for patients with advanced/metastatic GC. However, the heterogeneity of this neoplasia makes the practical application of such approaches difficult. Unfortunately, scientific progress has not been matched by progress in clinical practice in terms of significant improvements in prognosis. Survival continues to be low in contrast to the reduction in deaths from many common cancers such as colorectal, lung, breast, and prostate cancers. Although several target molecules have been identified on which targeted drugs can act and novel products have been introduced into experimental therapeutic protocols, the overall approach to treating advanced stage GC has not substantially changed. Currently, surgical resection with adjuvant or neoadjuvant radiotherapy and chemotherapy are the most effective treatments for this disease. Future research should not underestimate the heterogeneity of GC when developing diagnostic and therapeutic strategies aimed toward improving patient survival.

Astragaloside IV Inhibits the Progression of Non-Small Cell Lung Cancer Through the Akt/GSK-3β/β-Catenin Pathway

Astragaloside IV (AS-IV) is an active ingredient in Astragalus membranaceus and is involved in various biological processes, such as regulating the immune system, and counteracting inflammation and malignancy. The aim of this study was to explore the effect of AS-IV on non-small cell lung cancer (NSCLC) cells. Cell counting kit (CCK)-8 assay and flow cytometry were performed to investigate cell survival and cell death, and Western blotting was performed to assess protein expression. We found that AS-IV inhibited the migration and proliferation of NSCLC cells and caused a noticeable increase in cell death. Furthermore, the expression of Bax, a marker of cell death, was increased, whereas the expression of Bcl-2, an antiapoptotic protein, was reduced. AS-IV also promoted cleavage of caspase-3, another indication of apoptosis. Finally, the Akt/GSK-3β/β-catenin axis was suppressed in response to AS-IV. Taken together, these findings provide evidence that AS-IV inhibits NSCLC development via inhibition of the Akt/GSK-3β/β-catenin signaling axis. We therefore propose that AS-IV represents a promising novel agent for the treatment of NSCLC.

[Thioridazine Sensitizes Apoptotic Effect of TRAIL in Human Lung Cancer PC9 Cells Through ER Stress Mediated Up-regulation of DR5]

背景与目的

肿瘤坏死因子相关凋亡诱导配体（tumor necrosis factor-related apoptosis-inducting ligand, TRAIL）可诱导肿瘤细胞发生凋亡，然而相当数量的肿瘤细胞可耐受TRAIL诱导的凋亡而得以存活。本实验观察硫利达嗪（thioridazine, THZ）通过诱导内质网应激（endoplasmic reticulum stress, ER stress）介导的死亡受体5（death receptor 5, DR5）表达上调，继而增敏TRAIL对肺腺癌细胞PC9的生长抑制及凋亡诱导效应，探讨其机制。

方法

不同浓度硫利达嗪及TRAIL单独或联合处理PC9细胞，MTT法检测细胞活性变化，流式细胞术检测细胞表面DR5表达及细胞凋亡率，Western blotting检测内质网应激相关蛋白GRP78（glucose regulated protein 78）、C/EBP环磷酸腺苷反应元件结合转录因子同源蛋白（C/EBP homologous protein, CHOP）、p-PERK（PKR-like ER kinase）、p-eIF2α（eukaryotic initiation factor-2α, eIF2α）、ATF4（activating transcription factor 4, ATF4）及凋亡相关蛋白Caspase-3、Caspase-9、Caspase-8、PARP、DR5表达变化。

结果

硫利达嗪对PC9细胞的增殖抑制效应呈浓度依赖性（P < 0.05），硫利达嗪可增加TRAIL对PC9细胞的抑制作用及凋亡诱导作用且可上调PC9细胞表面DR5表达水平，流式细胞术结果显示：TRAIL联合硫利达嗪组细胞凋亡率较单独TRAIL组显著增加（P < 0.05），Western blotting结果显示：TRAIL联合硫利达嗪组细胞Cleaved-caspase-8、Cleaved-PARP、DR5表达水平较单独TRAIL组明显上调。DR5表达上调及促凋亡效应是通过诱导内质网应激发生，并伴随着GRP78及CHOP表达上调发生的，且该效应可被4-苯基丁酸（4-phenylbutyric acid, 4-PBA）可抑制（P < 0.05）。

结论

硫利达嗪增敏TRAIL对PC9细胞的增殖抑制效应显著，其机制可能与硫利达嗪内质网应激介导的DR5上调有关。