Nrf3 Promotes 5-FU Resistance in Colorectal Cancer Cells via the NF-κB/BCL-2 Signaling Pathway In Vitro and In Vivo

Figure 6

Nrf3 increased 5-FU resistance of colon cancer cells in vivo. HT29 and HT29/Nrf3 tumor models were established to observe the antitumor effect of 5-FU in vivo. Mice were treated with DMSO or 5-FU (25 mg/kg/day) for 14 days at the same time (IP injection, n = 5 per group). (a) Tumor growth curve. (b) The typical photos of tumor. (c) The average tumor weights of each group. These results showed that 5-FU has a lower anticancer effect on HT29/Nrf3 than HT29. Data are shown as mean ± SD. (d) Typical graph of immunohistochemical staining of Nrf3, RELA, and BCL-2 in tumor tissues (×200). (e) The average staining intensities of Nrf3, RELA, and BCL-2. The results showed that Nrf3 significantly increased the expression of RELA and BCL-2 (). (f) Sections showing typical apoptosis in tumor tissues. (g) Apoptotic index within tumor tissues. As shown in Figures 6(f) and 6(g), the group with Nrf3 overexpression showed a significant decrease of apoptotic cells in tumor tissues (HT29/Nrf3 compared to the control (HT29) (). Data are expressed as the mean apoptotic index ± SD.

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