Fig. 3: Fasting and CBIs cooperate to slow tumour growth by reducing circulating insulin, IGF1 and leptin.

a Capan-1 cells were treated for 96 h with standard FBS (10%) and glucose (1 g/L) concentration (standard CC), standard FBS, but low glucose (0.5 g/L) concentration, low FBS (1%), but standard glucose concentration, or FMCC (1% FBS, 0.5 g/L glucose). During the last 72 h, cells were also stimulated w/ or w/o 15 μM clotrimazole or 30 μM terbinafine. Thereafter, cell viability was determined. b Serum was collected before treatment onset and at the end of the experiment from the animals presented in Fig. 2h (HCT116 xenografts) and Igf1, c-peptide and leptin concentrations were measured by ELISA. c Capan-1 cells were treated for 96 h w/ or w/o FMCC and for the last 72 h w/ or w/o 20 μM terbinafine, IGF1 (5 ng/ml), leptin (50 ng/ml), insulin (500 pM), or IGF1+leptin+insulin (“fasting-reduced factors” combination, FRFs comb.). Thereafter, cell viability was measured. d Capan-1 cells were treated for 48 h w/ or w/o FMCC, IGF1 (5 ng/ml), leptin (50 ng/ml), insulin (500 pM), or IGF1+leptin+insulin. 20 μM terbinafine was added during the last 24 h. Thereafter, cellular cholesterol content was measured. e–g Capan-1 xenografts were established in 6-8-week-old female athymic nude mice. Once tumours were palpable, mice were randomized to be treated with ad lib. diet (n = 8), weekly 48 h water-only fasting (n = 11), terbinafine (n = 11), combined fasting plus terbinafine (n = 12), fasting plus terbinafine and human LDL (n = 8) or fasting, terbinafine and combined intraperitoneal (i.p.) injection of insulin, IGF1 and leptin (“fasting-reduced factors” combination, FRFs comb.; n = 13). Tumour volume was determined at the indicated time points (e). At the end of the experiment, tumours were weighted (f) and used for cholesterol content determination (g). In (e), n indicates the number of tumours per treatment group. In (a, c, d), data points are experimental replicates. In (b, f, g), data points are biological replicates: they represent sera from different animals (b) or single tumours (f, g). In (a–d, f–g) data are shown as mean ± SD and p values were calculated by two-tailed Student’s t test. In (e), data are shown as mean ± SEM and p values were determined by one-way ANOVA with Tukey post-test. Source data are provided as a Source Data file.