Chalcomoracin inhibits cell proliferation and increases sensitivity to radiotherapy in human non-small cell lung cancer cells via inducing endoplasmic reticulum stress-mediated paraptosis.

Chalcomoracin (CMR) is a kind of Diels-Alder adduct extracted from the mulberry leaves. Recent studies showed that CMR has a broad spectrum of anticancer activities and induces paraptosis in breast cancer and prostate cancer cells. In this study, we investigated the effects of CMR against human non-small cell lung cancer cells and the underlying mechanisms. We found that CMR dose-dependently inhibited the proliferation of human lung cancer H460, A549 and PC-9 cells. Furthermore, exposure to low and median doses of CMR induced paraptosis but not apoptosis, which was presented as the formation of extensive cytoplasmic vacuolation with increased expression of endoplasmic reticulum stress markers, Bip and Chop, as well as activation of MAPK pathway in the lung cancer cells. Knockdown of Bip with siRNA not only reduced the cell-killing effect of CMR, but also decreased the percentage of cytoplasmic vacuoles in H460 cells. Moreover, CMR also increased the sensitivity of lung cancer cells to radiotherapy through enhanced endoplasmic reticulum stress. In lung cancer H460 cell xenograft nude mice, combined treatment of CMR and radiation caused greatly enhanced tumor growth inhibition with upregulation of endoplasmic reticulum stress proteins and activation of pErk in xenograft tumor tissue. These data demonstrate that the anticancer activity and radiosensitization effect of CMR result from inducing paraptosis, suggesting that CMR could be considered as a potential anticancer agent and radiation sensitizer in the future cancer therapeutics.

Thermo-responsive magnetic liposomes for hyperthermia-triggered local drug delivery.

We prepared and characterised thermo-responsive magnetic liposomes, which were designed to combine features of magnetic targeting and thermo-responsive control release for hyperthermia-triggered local drug delivery. The particle size and zeta-potential of the thermo-responsive magnetic ammonium bicarbonate (MagABC) liposomes were about 210 nm and -14 mV, respectively. The MagABC liposomes showed encapsulation efficiencies of about 15% and 82% for magnetic nanoparticles (mean crystallite size 12 nm) and doxorubicin (DOX), respectively. The morphology of the MagABC liposomes was visualised using transmission electron microscope (TEM). The MagABC liposomes showed desired thermo-responsive release. The MagABC liposomes, when physically targeted to tumour cells in culture by a permanent magnetic field yielded a substantial increase in intracellular accumulation of DOX as compared to non-magnetic ammonium bicarbonate (ABC) liposomes. This resulted in a parallel increase in cytotoxicity for DOX loaded MagABC liposomes over DOX loaded ABC liposomes in tumour cells.

Phase II trial of gefitinib in pretreated Chinese women with advanced non-small-cell lung cancer.

A phase II clinical trial was performed to evaluate the efficacy and safety of gefitinib on pretreated Chinese female non-small-cell lung cancer (NSCLC) patients. Chinese female patients with locally advanced or metastatic NSCLC who failed at least one platinum-based chemotherapy received gefitinib monotherapy (250 mg/day) between April 2002 and January 2010. The primary endpoint was overall response rate (ORR), and secondary endpoints were overall survival (OS) and progression-free survival (PFS). Of the 40 evaluable female patients, the ORR was 62.5%. All patients have responded with one (2.5%) complete response, 24 (60%) partial response, 12 (30%) stable disease, and 3 (7.5%) progressive disease. The OS and PFS were 20 months (95% CI: 11.9-28 months) and 13 months (95% CI: 8.0-17.9 months), respectively. Survival (OS and PFS) were longer in patients with good performance status and in patients older than 65 years (P < 0.05). The most frequently observed toxicities were rash/dry skin (80%), diarrhea (42.5%), and vomiting/anorexia (32.5%). Four patients developed grade 3 toxicities (rash and diarrhea) but did not require either dose reduction or discontinuation. Gefitinib is a highly effective and well-tolerated agent for Chinese women with pretreated advanced NSCLC.