Fig. 6: Detection of chemo-resistant ESCC biomarkers in patient pathological specimens.

a Dose-response curves of ESCCOs after the treatment with CDDP. After the seeding of ESCC cells at day 0, CDDP was added from day 5 to day 10. Cell viability was measured on day 10. Data are presented as means of technical triplicates. One or two experiments were performed for each ESCCO. b Heat map showing AUC values for each ESCCO treated with CDDP. c The rank of Spearman correlation coefficients (r) for genes whose expression levels are positively correlated with the dose-response curve AUC values of CDDP in ESCCOs. Only genes with an r > 0.5 and mean TPM > 50 were plotted. A total of 117 genes were identified as positively correlated genes. d Gene ontology analysis of CDDP resistance-associated genes (r > 0.5, p-value < 0.05, and mean TPM > 50). Bar chart showing the top 10 GO terms for biological process, ranked by -Log10 p-value. e Scatter plot, with the line of best fit, showing the correlation between dose-response curve AUC values of CDDP [x-axis] and ALDH3A1 mRNA expression level (TPM) [y-axis] in each ESCCO line. Correlation coefficients (r) and p-values are also shown. f Detection of ALDH3A1, SPP1, and TXNRD1 mRNA by RNAscope in pathological specimens from patients #15, 17, 18, and 20. ESCCOs derived from patients #15 and 17 were chemo-resistant, and ESCCOs derived from patients #18 and 20 were chemo-sensitive. g Quantification of the area of the mRNA molecule spot relative to the area of the tumor region using QuPath software. n = 5 technical replicates for each sample. Data are presented as means are (%) ± s.d. Statistical significance was determined by a two-tailed Mann–Whitney test (ALDH3A1: p < 0.0001; SPP1: p < 0.0001; TXNRD1: p < 0.0001).