Extended Data Fig. 9: Regulation of UPP1 expression is independent of c-MYC.

a. Western blot showing Myc inhibition by 10058-F4 in ASPC1 cells after 24 h of culture. On the right: UPP1 mRNA expression determined by qPCR. kDa, unit for molecular weight. b. Western blot of Myc inhibition by Fedratinib in ASPC1 cells after 24 h of culture. On the right: UPP1 mRNA expression determined by qPCR. c. CiiDER analysis of transcription factor binding sites in the promoters of mouse and human UPP1. Myc binding sites were not detected. Details of analysis is in the “Methods” section. d. qPCR showing UPP1 expression upon uridine supplementation with or without basal glucose concentration in culture medium. e. RNA seq data showing the expression of Upp1 in sorted tumour cells and in KPC cells cultured in vitro in regular RPMI culture medium or tumour interstitial fluid medium (TIFM). Sample sizes: Tumour, n = 6, RPMI, n = 3 biologically independent cell samples, TIFM, n = 3 biologically independent cell samples. Normalized by log transformation [log2 (count +1)]. Statistical significance was measured using one-way ANOVA with Dunnett’s multiple comparisons test. Comparison between RPMI and TIFM group, ****P < 0.0001 or tumour group, ****P < 0.0001. Statistics and reproducibility: a, qPCR, n = 3 biologically independent samples per group. b. n = 3 biologically independent samples per group. Blots shown (a-b) are representative of two biological and technical replicate analyses with similar results. d. n = 3 biologically independent samples per group per cell line. Statistical significance was measured using one-way ANOVA with Tukey’s multiple comparisons test. PATU8988S (comparison between no glucose and no glucose + 1 mM uridine: P = ns (0.994); comparison between cells cultured in glucose-containing medium with and without uridine: **P = 0.005); comparison between no glucose and glucose: *P = 0.0316; CAPAN2 (comparison between no glucose and no glucose + 1 mM uridine: ****P < 0.0001; comparison between cells cultured in glucose-containing medium with and without uridine: P = ns (0.8688); DANG (comparison between no glucose and no glucose + 1 mM uridine: ****P < 0.0001; comparison between cells cultured in glucose-containing medium with and without uridine: *P = 0.0021); ASPC1 (comparison between no glucose and no glucose + 1 mM uridine: ****P < 0.0001; comparison between cells cultured in glucose-containing medium with and without uridine: P = ns (0.5339). Comparison between no glucose and glucose for CAPAN2, DANG and ASPC1: ****P < 0.0001. Data (a,b,d,e) shown as mean ± s.d.