Quick regression of brain metastases from lung adenocarcinoma with epidermal growth factor receptor-tyrosine kinase inhibitor treatment: A case report and literature review

Brain metastasis (BM) commonly occurs in patients with advanced lung cancer, and is associated with poor prognosis and limited treatment options, particularly for end-stage patients who are in poor physical and mental state. We herein present a case of lung adenocarcinoma with BM, as revealed by tumor marker and imaging studies. The patient was a 74-year-old woman who was diagnosed with lung adenocarcinoma with several metastatic lesions in the mediastinal lymph nodes, bone and brain. The patient underwent two cycles of chemotherapy, but the cancer recurred with enlarged BM, resulting in confusion and body dysfunction. The patient then received epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy with icotinib. After approximately 12 h of treatment the symptoms disappeared, and the metastatic lesions in the brain largely regressed in the following months. Our case indicates that the EGFR-TKI icotinib may provide a rapid and safe approach for emergency situations with BM from lung adenocarcinoma.

Effects of tetraspanin CD151 inhibition on A549 human lung adenocarcinoma cells

Tetraspanin protein CD151 is overexpressed in a wide variety of cancer types, including lung cancer, and is closely associated with metastasis and poor prognosis of carcinoma. To investigate whether knockdown of CD151 expression can inhibit the malignant biological behavior of lung adenocarcinoma (LAC), RNA interference technology (RNAi) was used to silence CD151 expression in the A549 LAC cell line. Specific small interfering RNA (siRNA) for targeting human endogenous CD151 were delivered into A549 cells in order to examine the effects on cell proliferation, survival, migration, invasion and colony formation. The expression levels of CD151 were assayed by western blotting, proliferation was evaluated by MTT method and apoptosis was determined by flow cytometry. The invasive and metastatic ability of A549 cells was investigated by wound healing and Boyden chamber assays. Colony formation analysis was used to determine the A549 cell growth properties. Finally, the expression of phosphorylated FAK, PI3K‑AKT, MEK‑Erk1/2, MMPs, and VEGF was detected by western blotting. The results demonstrated that CD151‑siRNA significantly decreased the expression level of CD151 in A549 cells. Reduced CD151 expression in A549 cells lead to the inhibition of cellular proliferation, migration, invasion and colony formation and an enhancement of apoptosis. Furthermore, the expression of tumor development‑related proteins, including FAK, PI3K‑AKT, MEK‑ERK1/2MAPK as well as the expression of MMP9 and VEGF, were restrained. Taken together, the present study has shown that CD151 expression is essential for LAC progression. Thus, knockdown CD151 expression by targeted siRNA could inhibit the related downstream intercellular signaling pathways, and this may provide a novel gene therapy for patients with LAC.

Icotinib: activity and clinical application in Chinese patients with lung cancer

INTRODUCTION

Icotinib (BPI-2009H, Conmana) is a novel oral quinazoline compound that has proven survival benefit in Chinese patients with lung cancer, for which several therapies are currently available often with unsatisfactory results. Icotinib is the first self-developed small molecular drug in China for targeted therapy of lung cancer.

AREAS COVERED

The authors' experience in the clinical application of icotinib is reviewed in combination with related publications in the literature. Antitumor activities were observed in non-small-cell lung cancer and others in several recent studies. On 7 June 2011, icotinib was approved by the State Food and Drug Administration of China for the treatment of local advanced or metastatic non-small-cell lung cancer based on the results of a nationwide, of 27 centers, randomized, double-blind, double-modulated, parallel-controlled, Phase III trial with single agent icotinib in lung cancer patients after failure of chemotherapy.

EXPERT OPINION

Icotinib is a generic drug. Compared to the other two commercially available EGFR tyrosine kinase inhibitors, gefitinib and erlotinib, icotinib is similar to them in chemical structure, mechanism of activity and therapeutic effects but less expensive. Better safety as well as a wider therapeutic window has also been proven in several Chinese studies. Future studies on cost effectiveness are warranted.