Quinoline-Based Compound BPIQ Exerts Anti-Proliferative Effects on Human Retinoblastoma Cells via Modulating Intracellular Reactive Oxygen Species

Retinoblastoma (Rb) is the most common primary intraocular malignant tumor of childhood. It is important to develop the strategy for Rb treatment. We have tested a quinolone derivative 2,9-bis[2-(pyrrolidin-1-yl)ethoxy]-6-{4-[2-(pyrrolidin-1-yl)ethoxy]phenyl}-11H-indeno[1,2-c]quinolin-11-one (BPIQ) for its anti-cancer effects against Rb via cultured human Rb cell line Y79. Our results showed that BPIQ significantly inhibits cell growth of Y79. Furthermore, the flow cytometer-based assays and Western blotting showed that BPIQ induces the apoptosis of Y79 via increasing the level of reactive oxygen species (ROS). Besides, the activation of γH2AX, a DNA damage sensor in human Y79 cells was also observed, indicating the potential of BPIQ for causing DNA damage of Rb cells. On the contrary, BPIQ-induced apoptosis of Y79 cells was attenuated significantly by N-acetyl-L-cysteine (NAC), an ROS scavenger. The results of Western blot showed that BPIQ down-regulates the levels of anti-apoptotic proteins Bcl-2, survivin and XIAP while up-regulates the pro-apoptotic proteins Bad, Bax and Bid. Our present study demonstrated the anti-proliferative effect of BPIQ in human Y79 cells. The inhibitory effect of BPIQ on the proliferation of Y79 cells is, at least, partly mediated by the regulation of ROS and DNA damage pathway. In conclusion, BPIQ may provide an alternative option in the chemotherapeutics or chemoprevention on the Rb therapy in the future.

The treatment of retinoblastoma with four-drug regimen including cisplatin, etoposide, vincristine, and cyclophosphamide

Over an 11-year period, 59 patients (83 eyes) were treated with four-drug chemotherapy (cisplatin, etoposide, cyclophosphamide, and vincristine) at Hacettepe University, Departments of Ophthalmology and Pediatric Oncology. We evaluated the clinical features, treatment modalities, and outcome of these patients with a median follow-up of 55 months (range 9-130 months). Enucleation was performed as a first-line treatment for 30 eyes due to iris neovascularization and neovascular glaucoma, tumor in the anterior chamber regardless of the tumor stage, and for the patients with the Reese-Ellsworth (RE) group Vb. Chemotherapy was given regardless of tumor stages according to the RE groups in all 59 patients (83 eyes). Fifty-three eyes were treated with chemoreduction (CRD) and focal treatment. The rates of globe preservation were 87% for bilateral tumors and 35% for unilateral tumors in the CRD group. The 5-year overall (OS) and enucleation-free survival (EnFS) was 86.9% and 40%, respectively, for the whole group. At 3rd year, ocular survival rate for the eyes with vitreal or subretinal seeding was 58% and without seeding was 66% (P = .78). Seeding or subretinal collection may not indicate poor prognosis under intensive chemotherapy. The intensive four-drug chemotherapy protocol might have satisfactory results in the retinoblastoma (RBL) patients.