Although 24 hours after incubation with or without MMC no relevant changes in HSP27 expression were detected in HT-29 cells, upregulated expression as in SW480 for 5-FU tumor cells was demonstrated after 48 and 72 hours: hyperthermia alone resulted in intense HSP27 expression compared with normothermic controls and additional exposure to MMC caused further increase in expression (Figure 2A). This evidence concerns the gene HSPB1 and neoplasm.