Review of "bioinformatics basics: applications in biological science and medicine" by Buehler & Rashidi

Chinese hamster cells (V79 379A) cells from a human small cell carcinoma of the lung (ME/MAR) and two xenografted human melanomas (HX117 and HX118) have been grown as multicellular spheroids in vitro. The radiation response of these four cell types has been compared when grown as spheroids (200 or 400 pm in diameter) and as single cells from disaggregated spheroids. The radiation sensitivity of tne three human lines irradiated as single cells in air, is similar. In comparison, the V79 cells are more radioresistant. Only the V79 and HX 118 cells show a spheroid size dependent radiation response. The radiation response of spheroids has been assayed using both cell survival and growth delay. V79, ME/MAR and HX 1 17 cells demonstrate a good correlation between the two endpoints whereas with HX 1 18 there appears to be greater cell kill for a given level of growth delay. This may be because HXl 18 is efficient in the repair of potentially lethal damage (PLD). The results support the view that extrinsic factors such as three dimensional contact, hypoxia and repair of PLD can be important and together with the intrinsic cell radiosensitivity will determine the radiation response of tumours. Multicellular spheroids have many characteristics which make them an interesting in vitro model of small solid tumours. In radiobiological studies of Chinese hamster V79 spheroids the importance of have been demonstrated. A simplified method of spheroid production using a static culture technique was described by Yuhas et al. (1977). Subsequently, cells from a variety of sources, including some of human origin, were shown to form spheroids and grow in culture undertook a study of spheroid formation by cells from a wide variety of xenografted human tumours (Jones et al., 1982). It was shown that there was a heterogeneity of response between the different cell types to a variety of chemotherapeutic drugs and this broadly reflected the xenograft response in the mouse. It has been suggested that the wide variation in radiocurability of human tumours may be less dependent upon the inherent radiation sensitivity of the cells than on extrinsic factors such as hypoxia and/or the repair of potentially lethal damage (PLD) (Weichselbaum et al., 1982) or on other so-called "contact effects" (Dertinger & Liicke-Hiihle, 1975; Durand, 1980). In order to provide information which might substantiate these suggestions we have compared the radiosensitivity of V79 spheroids and those of spheroids derived from two …