Antitumor activity of high-dose pulsatile gefitinib in non-small-cell lung cancer with acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors

In vitro and in vivo Study of a Novel Liposome-Mediated Dual Drug Delivery for Synergistic Lung Cancer Therapy via Oral Administration

Background

To establish the co-delivery liposomes of gefitinib (GFT) and curcumin (CUR) via oral administration with the goals of improving the synergistic effect and reducing acquired drug resistance.

Methods

We prepared liposomes (LPs) which can embed the anticancer compound GFT and CUR and investigated whether they could enhance the antitumor effects of anticancer drugs against MDR. The LPs system was characterized by transmission electron microscopy (TEM), particle size, encapsulation efficiency, cellular uptake and cell viability. In addition, the release characteristics and pharmacodynamics of the LPs were also studied in detail.

Results

The results showed that GFT/CUR LPs were characterized by small particle size of about 130 nm and negative zeta potential of about −22.2 mV, and the drug controlled to release slowly on a biphasic pattern. Compared with control groups, GFT/CUR LPs showed a higher cellular uptake and cell inhibition rates. Through pharmacodynamics analysis, we found that two compounds (GFT and CUR) were incorporated into one LPs carrier, which played a good role in synergistic effect.

Conclusion

Co-delivery of GFT and CUR has the potential to improve cancer treatment efficacy and overcome acquired resistance, especially towards GFT-resistant cells.

Co-Delivery Anticancer Drug Nanoparticles for Synergistic Therapy Against Lung Cancer Cells

Introduction

This study aims to develop a novel co-delivery gefitinib and quercetin system loaded with PLGA-PEG nanoparticles and evaluate their antitumor activity in vitro and in vivo.

Methods

Gef/Qur NPs were prepared and characterized. The release of drugs, stability, cellular uptake and cytotoxicity were evaluated in vitro. The antitumor effects and systemic toxicity of different formulations were also investigated.

Results

Gef/Qur NPs displayed a smaller particle size and a PDI and zeta potential of 0.11 and −23.5 mV, respectively. The hydrophobic Gef and Qur content in NPs reached up to 65.2% and 56.4%, respectively, and their high entrapment efficiencies recorded 83.7% and 82.3%, respectively. The in vitro release of Gef/Qur from the NPs was sustained for 12 h. Compared with control groups, Gef/Qur NPs showed higher cellular uptake and cell inhibition rates. In vivo studies identified the lungs as the target tissue and the region of maximum drug release. Through pharmacodynamics analysis, we found that two drugs (Gef and Qur) were incorporated into one nanoparticle carrier, which played a good role in generating synergistic effect.

Discussion

It is concluded that PLGA-PEG is an ideal drug carrier for the co-delivery of Gef/Qur to treat lung cancer.

Diffusion-Weighted Magnetic Resonance Imaging for Early Detection of Chemotherapy Resistance in Non-Small Cell Lung Cancer

Background

The aim of this study was to examine the role of magnetic resonance imaging-diffusion weighted imaging (MRI-DWI) in the early detection of chemotherapy resistance in non-small cell lung cancer (NSCLC) patients.

Material/Methods

MRI-DWI and computed tomography (CT) were carried out in 75 patients with newly diagnostic NSCLC before and after first, second, fourth, and sixth cycles of chemotherapy. Resistance to chemotherapy was assessed based on the change in the largest tumor diameter after chemotherapy. Diffusion of water molecule in each lesion was quantitatively measured by apparent diffusion coefficient (ADC). The diagnostic results of DWI after first and second cycle of chemotherapy were analyzed by the area under receiver operating characteristics curve (ROC).

Results

Among the patients, 43 patients were chemo-resistance while 32 patients were chemo-sensitive. The ADC changing rate between second and first cycle of chemotherapy was significantly higher in chemo-sensitive patients compared with chemo-resistance patients (t=3.236, P=0.002). The ROC showed cutoff values of the ADC changing rate after first and second cycles of chemotherapy for resistance/sensitive discrimination were 23.6% and 5.56%, respectively. DWI after first and second cycles of therapy showed sensitivities of 55.8% and 55.8%, specificities of 65.6% and 87.5%, and area under ROC of 0.568 and 0.733, respectively.

Conclusions

ADC changing rate between first and second cycles of chemotherapy could sensitively distinguish chemo-sensitive and chemo-resistant tumors at earlier stages, which may direct treatment adjustment and improve the prognosis of patients.

Gjb4 serves as a novel biomarker for lung cancer and promotes metastasis and chemoresistance via Src activation

Most lung cancer patients are diagnosed late with metastasis, which is the major cause of cancer-related death and recurrent tumors that often exhibit chemoresistance. In the present study, we initially identified gap junction beta-4 protein (Gjb4) to be overexpressed in highly metastatic cancer cells selected by their enhanced binding to serum components. Overexpression or knockdown of Gjb4 increased or decreased lung metastasis of syngeneic mice, respectively. We found that Gjb4 expression was higher in lung tumors than normal tissues (p = 0.0026), and Gjb4 levels in blood buffy coat samples showed significant performance in diagnosing stage I-III (p = 0.002814) and stage IV (p < 0.0001) lung cancer. Moreover, high Gjb4 expression levels were correlated with poor prognosis (p = 1.4e-4) and recurrence (p = 1.9e-12). Using syngeneic mouse model, we observed that Gjb4 was able to promote tumor growth. High molecular weight serum fraction containing the major growth factor component IGF1 was able to induce Gjb4 via PKC pathway. Gjb4 activated Src signaling via MET, and overexpression of Gjb4 enhanced sphere-forming ability and anchorage-independent growth, which were reversed by inhibition of Src. In addition, we demonstrated that Gjb4-mediated Src activation enhanced chemoresistance of cancer cells toward gemcitabine and etoposide. The combination of Gjb4 knockdown, gemcitabine, and dasatinib further enhanced the inhibition of cancer cell viability. Together, our study has identified Gjb4 as a potential novel diagnostic and prognostic biomarker for lung cancer. Targeting Gjb4 may be exploited as a modality for improving lung cancer therapy.

Anticancer effects of isofraxidin against A549 human lung cancer cells via the EGFR signaling pathway

Lung cancer is the leading cause of mortality due to tumor malignancy worldwide. In recent years, the treatment of lung cancer with chemotherapy has demonstrated notable resistance and insensitivity. Therefore, it is of great importance to investigate anti‑lung cancer drugs with high efficiency and low toxicity. In the present study, the effects of isofraxidin on lung cancer cells and the associated mechanisms were investigated. The results revealed that, in vivo and in vitro, isofraxidin exhibited marked inhibitory effects on the A549 lung cancer cell line. The results of Cell Counting kit‑8, Transwell migration and Matrigel invasion assays, and flow cytometry to determine apoptosis, revealed that isofraxidin significantly inhibited the proliferation, migration and invasion of A549 cells, and induced the cell apoptosis. Furthermore, western blot analysis demonstrated that isofraxidin treatment led to effects on the expression of apoptosis‑associated proteins, including members of the Bcl‑2 protein family, and invasion‑associated proteins, including matrix metallopeptidase (MMP)‑2 and MMP‑9, which may occur via inhibition of the expression of phosphorylated (p)‑epidermal growth factor receptor, p‑AKT and p‑extracellular signal‑regulated kinase. This regulation of protein expression may contribute to the inhibition of proliferation, migration and invasion of A549lung cancer cells by isofraxidin. In addition, despite the inhibitory effects on the A549 lung cancer cell line, the present study revealed that isofraxidin exhibited low toxicity towards BEAS‑2B normal lung epithelial cells within a certain dose range (0‑160 µM), indicating that isofraxidin may be employed for lung cancer treatment with hypotoxicity and fewer side effects. In conclusion, isofraxidin may be a novel candidate for anti‑lung cancer chemotherapy.