Retinoblastoma Cell Culturing and Evaluation of Their Drug Resistance

Assessment of the Chemosensitivity of Uveal Melanoma Cells Ex Vivo

The study was designed to create a primary cell culture of uveal melanoma and to evaluate its resistance to chemotherapy. Of the obtained 20 samples of uveal melanoma, the primary cultures with proliferation sufficient for MTT test were derived in only 7 cases. However, even these cultures were unable to survive more than 4 passages; the cells accumulated melanin and underwent apoptosis. Retinol palmitate and nepafenac produced no cytotoxic effect on uveal melanoma cells. Of 5 cultures treated with sodium valproate (Convulex), no pronounced cytotoxic effect was observed in one culture (UM4); in 2 cultures, 50% cells died in the presence of the lowest drug concentration of 1.88 mg/ml; and in 2 cultures, the same effect was achieved at drug concentrations 7-10 mg/ml. The cytotoxic effect of treosulfan was evaluated in only 4 cultures of uveal melanoma: the drug exhibited pronounced antitumor activity on all cultures, in 2 cases, it was effective at a concentration of 0.16 mg/ml. Gemcitabine in a concentration of 2.5 mg/ml produced a pronounced cytotoxic effect in 4 out of 7 cultures (death of 70-80% cells) and induced death of ~45% cells in the remaining 3 cultures. Mitoxantrone had ambiguous effect: in 2 of 5 cultures, the drug in high concentrations stimulated the growth of tumor cells, but in 3 cultures, the drug even in minimum concentrations induced death of 70-80% cells.

Development of In Vivo Model of Intraocular Retinoblastoma

Here we describe creation of a model of intraocular retinoblastoma on 4 mature immunodeficient BALB/c nude mice of both sexes. A suspension of the primary retinoblastoma culture was injected into each of the 8 eyes of the test animals. The injections were performed under the control of an operating microscope using insulin syringes with a diameter of 29G transsclerally into the subretinal space in a volume of 0.3 ml at a rate of 10,000 cells in 25 μl physiological saline. The culture of Rb10 cells derived from a patient with retinoblastoma passed 12 passages at the time of the experiments. After 9-week follow-up, a clinical (ophthalmoscopy) and instrumental (ultrasound) study was performed with visualization of the tumor mass on the fundus. After enucleation, a morphological study was performed. The retinoblastoma tumor nodes were identified in two eyes. The proposed model can be used for further research and for testing new chemotherapeutic drugs and treatment regimens for retinoblastoma.