PURPOSE: To investigate the radiosensitivity of uveal melanoma cell lines by a clonogenic survival assay, to improve the efficiency of the radiation regimen. METHODS: Four primary and four metastatic human uveal melanoma cell lines were cultured in the presence of conditioned medium. After single-dose irradiation (0-12 Gy), colonies were allowed to form for 6 to 14 days. Two cutaneous melanomas cell lines were also tested for comparison. The survival curves were analyzed by the linear quadratic (LQ) model, and the surviving fraction at a dose of 2 Gy (SF(2)), the SF at 10 Gy (SF(10)), the ratio of initial irreparably damaged DNA (alpha-coefficient) to the capacity to repair sublethally damaged DNA (beta-coefficient), and the plating efficiency were calculated. RESULTS: The melanomas displayed a wide range of initial irreparable DNA damage (alpha-component), as well as a capacity for repair of sublethal DNA damage (beta-component), which ultimately resulted in a wide range of alpha/beta ratios. These findings were similar in both primary and metastatic melanomas and were comparable with data obtained from two cutaneous melanomas. CONCLUSIONS: Cell lines obtained from primary and metastatic human uveal melanomas displayed a wide range of radiosensitivity, similar to that published for cutaneous melanomas. Translating these data to the clinical setting indicates that a fractionated dose of 8 to 10 Gy administered in three to four fractions, as currently delivered in many centers, should be sufficient to eradicate tumors of approximately 1 cm(3).
PURPOSE: To investigate the radiosensitivity of uveal melanoma cell lines by a clonogenic survival assay, to improve the efficiency of the radiation regimen. METHODS: Four primary and four metastatic humanuveal melanoma cell lines were cultured in the presence of conditioned medium. After single-dose irradiation (0-12 Gy), colonies were allowed to form for 6 to 14 days. Two cutaneous melanomas cell lines were also tested for comparison. The survival curves were analyzed by the linear quadratic (LQ) model, and the surviving fraction at a dose of 2 Gy (SF(2)), the SF at 10 Gy (SF(10)), the ratio of initial irreparably damaged DNA (alpha-coefficient) to the capacity to repair sublethally damaged DNA (beta-coefficient), and the plating efficiency were calculated. RESULTS: The melanomas displayed a wide range of initial irreparable DNA damage (alpha-component), as well as a capacity for repair of sublethal DNA damage (beta-component), which ultimately resulted in a wide range of alpha/beta ratios. These findings were similar in both primary and metastatic melanomas and were comparable with data obtained from two cutaneous melanomas. CONCLUSIONS: Cell lines obtained from primary and metastatic humanuveal melanomas displayed a wide range of radiosensitivity, similar to that published for cutaneous melanomas. Translating these data to the clinical setting indicates that a fractionated dose of 8 to 10 Gy administered in three to four fractions, as currently delivered in many centers, should be sufficient to eradicate tumors of approximately 1 cm(3).
Authors: Krzysztof Bilmin; Kamil J Synoradzki; Anna M Czarnecka; Mateusz J Spałek; Tamara Kujawska; Małgorzata Solnik; Piotr Merks; Mario Damiano Toro; Robert Rejdak; Michał Fiedorowicz Journal: Cancers (Basel) Date: 2021-12-28 Impact factor: 6.639