EGFR inhibitors as the first-line systemic treatment for advanced non-small-cell lung cancer

Efficacy of Gefitinib Combined with 125I Radioactive Particles in the Treatment of Transplanted Lung Cancer Tumors in Nude Mice

OBJECTIVE

To investigate the efficacy of gefitinib combined with iodine-125 (¹²⁵I) radioactive particles in the treatment of transplanted tumors of the lung cancer cell line A549 in nude mice.

MATERIALS AND METHODS

Twenty-four nude mice were inoculated with A549-luc human lung adenocarcinoma cells stably expressing luciferase. The tumor size was approximately 8-10 mm after 20 days. The mice were randomly divided into four groups: a control group (n = 6), an ¹²⁵I particles group (n = 6), a gefitinib group (n = 6) and a gefitinib combined ¹²⁵I particles implantation group (n = 6). Tumor growth was observed, and changes in tumor size were continuously measured. Bioluminescence imaging was used to detect the bioluminescence activity of human lung adenocarcinoma A549-luc cells containing the luciferase reporter gene in vivo. After 35 days, the nude mice were sacrificed, and a tumor growth curve was drawn.

RESULTS

Before treatment, the tumor volumes of the four groups were not significantly different. The tumor volume difference was statistically significant in the four groups (control group, ¹²⁵I radioactive particles, gefitinib group and combined drug group) at 5 weeks after treatment (F = 10.305, P < 0.05). The tumor size in the gefitinib combined with ¹²⁵I particles group was significantly smaller than that in the gefitinib, ¹²⁵I particles and control groups and significantly smaller than that before treatment. There was no significant difference in the bioluminescence signal intensity between the four groups before treatment. The numbers of biofluorescence photons difference were statistically significant in the four groups (F = 28.975, P < 0.05). The bioluminescence signal intensity in the gefitinib combined with ¹²⁵I particles group was significantly lower than that in the ¹²⁵I particles, gefitinib and control groups and significantly lower than that before treatment.

CONCLUSION

Gefitinib combined with ¹²⁵I radioactive particles brachytherapy can significantly inhibit tumor growth.

[Effect and Significance of BIM on Non-small Cell Lung Cancer]

B细胞淋巴瘤-2促细胞凋亡（B-cell lymphoma 2 interacting mediator of cell death, BIM）基因作为抑癌基因，在调控细胞凋亡中起重要作用。在非小细胞肺癌（non-small cell lung cancer, NSCLC）中，BIM表达水平的下调或功能缺陷会降低酪氨酸激酶抑制剂（tyrosine kinase inhibitors, TKIs）及化疗药物的疗效并影响术后患者的预后。本文将对BIM的结构、功能以及BIM在NSCLC治疗中的作用及意义进行介绍。

The Response, Outcome and Toxicity of Aggressive Palliative Thoracic Radiotherapy for Metastatic Non-Small Cell Lung Cancer Patients with Controlled Extrathoracic Diseases

BACKGROUND AND PURPOSE

For metastatic non-small cell lung cancer (NSCLC) patients with controlled extrathoracic disease after systemic treatment, stable or progressive primary lung lesions may cause respiratory symptoms and increase comorbidities. In the present study, we sought to investigate whether aggressive palliative thoracic radiotherapy (RT) can enhance local control and improve the survival for this subgroup of patients.

MATERIALS AND METHODS

Between March 2006 and December 2014, 56 patients with metastatic NSCLC who had responsive or stable extrathoracic diseases after chemotherapy and/or molecular targets, and received thoracic RT for stable and progressive primary lung lesions were included. RT with a median dose of 55 Gy (range, 40-62 Gy) was administered in 1.8-2.5 Gy fractions to primary lung tumor and regional mediastinal lymph nodes using modern RT technique. Overall survival (OS) from diagnosis, and locoregional progression-free survival (LRPFS), and survival calculated from radiotherapy (OS-RT) were estimated using the Kaplan-Meier method.

RESULTS

There were 37 men and 19 women with a median age of 60 years at diagnosis. The median interval from the diagnosis of metastatic disease to thoracic RT was 8 months. Following thoracic RT, 26 patients (46%) achieved complete or partial response (overall response rate, ORR). Patients with squamous cell carcinoma or poorly-differentiated carcinoma had a higher ORR than those with adenocarcinoma (63% vs. 34%, P = 0.034). EGFR mutations was closely associated with a better ORR (45% vs. 29%, P = 0.284). At a median follow-up time of 44 months, the median OS, LRPFS after RT, and OS-RT were 50 months, 15 months, and 18 months.

CONCLUSION

Radical palliative throractic RT is safe and might be beneficial for primary lung lesions of metastatic NSCLC patients with controlled extrathoracic diseases.

Bcl-2-like protein 11 deletion polymorphism predicts survival in advanced non-small-cell lung cancer

INTRODUCTION

Germline Bcl-2-like protein 11 (BIM) deletion polymorphism in Asian is a poor predictive factor for treatment outcomes to tyrosine kinase inhibitors (TKIs) in malignancies. We explored the impact of BIM deletion polymorphism on treatment outcome of advanced non-small-cell lung cancer (NSCLC).

METHODS

We prospectively collected tissue samples, blood, and clinical data from two cohorts of advanced NSCLC patients. BIM deletion polymorphism was correlated with overall survival (OS) and progression-free survival (PFS) to epidermal growth factor receptor (EGFR) TKIs and chemotherapy treatment.

RESULTS

BIM deletion polymorphism was detected in blood of 16.2% (33 of 204) patients. The PFS to first-line EGFR-TKIs in 153 patients were 8.6 and 4.6 months for patients with wild-type BIM and BIM deletion polymorphism, respectively (p = 0.004). Among 120 patients who received chemotherapies, the PFS to chemotherapies were 5.6 and 3.5 months for patients with wild-type BIM and BIM deletion polymorphism, respectively (p = 0.050). The OS of all 204 patients was 24.8 and 16.8 months for patients with wild-type BIM and BIM deletion polymorphism, respectively (p = 0.005). Multivariate analyses suggested that BIM deletion polymorphism was an independent predictor for shorter PFS to EGFR-TKIs (hazard ratio [HR] 2.15, p = 0.002), PFS to chemotherapy (HR 2.40, p = 0.016), and OS (HR 1.65, p = 0.039).

CONCLUSIONS

BIM deletion polymorphism predicts shorter PFS to EGFR-TKIs and OS in advanced NSCLC.

Dichloroacetate treatment accelerates the development of pathology in rodent autosomal recessive polycystic kidney disease

Dichloroacetate (DCA) is a toxicant by-product from the chlorination disinfection process for municipal water. The levels would not affect people with normal renal and liver function. However, people with impaired renal or liver function may have an increased susceptibility to DCA toxicity as those are the organs affected by DCA. People (and rodents) with polycystic kidney disease (PKD) are polyuric, drink more fluids, and have both renal and liver pathology. In PKD, renal tubules and biliary epithelial cells proliferate to form cysts, which can eventually cause renal and/or liver dysfunction. Therefore, PKD may be a predisposing condition with an increased sensitivity to DCA toxicity. PCK rats are an orthologous model of human autosomal recessive PKD and were treated with 75 mg/l DCA in their drinking water. Male and female PCK and male Sprague-Dawley rats were treated from 4 to 8 wk of age, after which the severity of the renal and liver pathology induced by DCA were assessed. Only male PCK rats were adversely affected by DCA treatment, with an increase in the severity of renal cystic disease evinced by an increase in cystic enlargement and proteinuria. In conclusion, the chlorination byproduct DCA may adversely affect those with a preexisting renal disease, especially those who are polydipsic, like those with PKD.

Antibodies directed against receptor tyrosine kinases: current and future strategies to fight cancer

Approximately 30 therapeutic monoclonal antibodies have already been approved for cancers and inflammatory diseases, and monoclonal antibodies continue to be one of the fastest growing classes of therapeutic molecules. Because aberrant signaling by receptor tyrosine kinases (RTKs) is a commonly observed factor in cancer, most of the subclasses of RTKs are being extensively studied as potential targets for treating malignancies. The first two RTKs that have been targeted by antibody therapy, with five currently marketed antibodies, are the growth factor receptors EGFR and HER2. However, due to systemic side effects, refractory patients and the development of drug resistance, these treatments are being challenged by emerging therapeutics. This review examines current monoclonal antibody therapies against RTKs. After an analysis of agents that have already been approved, we present an analysis of antibodies in clinical development that target RTKs. Finally, we highlight promising RTKs that are emerging as new oncological targets for antibody-based therapy.

Discovery and Biological Evaluation of Novel Dual EGFR/c-Met Inhibitors

Activating mutations in the epidermal growth factor receptor (EGFR) have been identified in a subset of non-small cell lung cancer (NSCLC), which is one of the leading cancer types worldwide. Application of EGFR tyrosine kinase inhibitors leads to acquired resistance by secondary EGFR mutations or by amplification of the hepatocyte growth factor receptor (c-Met) gene. Although several EGFR and c-Met inhibitors have been reported, potent dual EGFR/c-Met inhibitors, which can overcome this latter resistance mechanism, have hitherto not been published and have not reached clinical trials. In the present study we have identified dual EGFR/c-Met inhibitors and designed novel N-[4-(quinolin-4-yloxy)-phenyl]-biarylsulfonamide derivatives, which inhibit the c-Met receptor and both the wild-type and the activating mutant EGFR kinases in nanomolar range. We have demonstrated by Western blot analysis that compound 10 inhibits EGFR and c-Met phosphorylation at cellular level and effectively inhibits viability of the NSCLC cell lines.