Figures & data
Figure 1 Nrf2 and HO-1 were consistently located in vitro and were upregulated in human ccRCC tissues.
Notes: (A) Nrf2 and HO-1 were consistently located in the 786-O, OS-RC-2, A498, and ACHN cell lines using immunofluorescence. Scale bar, 50µm. (B) Nrf2 and HO-1 protein levels were upregulated in ccRCC tissues. (C) Pearson’s correlation curves are shown, revealing the positive relationship between Nrf2 and HO-1 expression.
Abbreviation: ccRCC, clear cell renal cell carcinoma.
Figure 2 Nrf2 and HO-1 were expressed both in ccRCC and adjacent normal tissues. Expression scoring was performed as follows: the staining of tumors was quantitated by determining the percentage of positive cells and the staining intensity (Scale bar, 50µm).
Notes: The intensity of cell staining was categorized as follows: 0, negative staining; 1, weak staining; 2, moderate staining; and 3, strong staining. The extent scores (percentages of cells stained positive) were as follows: 0, no positive cells; 1, positive cells staining <10%; 2, 11%–30% of cells; 3, 31%–60%; 4, 61%–90% of cells; and 5, the percentage of positive cells staining >90%. The final staining score was calculated by adding the points from the positive cell percentage and the staining intensity. A score of 0 points was considered negative expression (–), 1–3 points were considered weakly positive expression (+), 4–6 points were considered moderately positive expression (++), and 7–8 points were considered strongly positive expression (+++).
Abbreviation: ccRCC, clear cell renal cell carcinoma.
Figure 3 Positive immunostaining was predominantly localized in the cytoplasm.
Notes: Low levels of nuclear staining were also evident in some cancer cells. (A) H&E staining in ccRCC tissue. Scale bar, 20 µm. (B) Some scattered Nrf2 nucleus-positive cells were observed in ccRCC tissue (shown by black arrows, scale bar, 20 µm). (C) Some scattered HO-1 nucleus-positive cells were observed in ccRCC tissue (shown by black arrows, scale bar, 20 µm).
Abbreviation: ccRCC, clear cell renal cell carcinoma.
Table 1 The difference expression of Nrf2/HO-1 in ccRCC
Table 2 Correlation analysis between Nrf2/HO-1 protein expression and clinicopathological parameters
Table 3 Correlation between Nrf2 protein expression and HO-1 protein in ccRCC tissues
Figure 4 Kaplan–Meier survival curves were performed to determine the MST and OS rate.
Notes: (A) Patients with a high expression level of Nrf2 or HO-1 tended to have a worse prognosis. (B) Additionally, patients with a high expression level of HO-1 tended to have a worse prognosis.
Abbreviations: ccRCC, clear cell renal cell carcinoma; MST, mean survival time; OS, overall survival.
Figure 5 Simultaneous analysis of the protein expression levels in carcinoma and adjacent normal tissues.
Notes: The Kaplan–Meier survival estimate was performed to determine the MST and OS rate. (A) The group highly expressing Nrf2 in cancer tissues but not in paracancerous tissues had the worst prognosis of all the subgroups (log-rank P=0.005, HR =4.932). (B) There was a group with high expression levels of HO-1 in cancer tissues but not in paracancerous tissues had the worst prognosis (log-rank P=0.002, HR =7.436). (C) Patients with low levels of expression of Nrf2 in ccRCC but positive expression of Nrf2 in paracancerous tissues had better prognoses (log-rank P=0.044, HR =0.159). (D) The HO-1 protein was expressed at low levels in ccRCC and at higher levels in paracancerous tissues, and the patient’s prognosis was better (log-rank P=0.378, HR =0.400).
Abbreviations: ccRCC, clear cell renal cell carcinoma; MST, mean survival time; OS, overall survival.
Table 4 Kaplan–Meier survival analysis based on different subgroups
Table 5 Cox regression: univariate/multivariate analysis