Table 4.
Association of BRCA1 promoter methylation with mitosis, immunohistochemistry, and molecular subtype of breast cancer.
| Overall (N = 40) | % | BRCA1 methylation in normal tissues | BRCA1 methylation in cancer tissues | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Methylated (14) | Unmethylated (26) | p value | Methylated (17) | Unmethylated (23) | p value | |||||||
| Freq. | (%) | Freq. | (%) | Freq. | (%) | Freq. | (%) | |||||
| Mitosis: | ||||||||||||
| 0 | 4 | 10.0% | 0 | (0) | 4 | (15.4) | 0.292 | 0 | (0.0) | 4 | (17.4) | 0.042∗ |
| 1 | 5 | 12.5% | 3 | (21.4) | 2 | (7.7) | 4 | (23.5) | 1 | (4.3) | ||
| 2 | 29 | 72.5% | 10 | (71.4) | 19 | (73.1) | 13 | (76.5) | 16 | (69.6) | ||
| 3 | 2 | 5.0% | 1 | (7.1) | 1 | (3.8) | 0 | (0.0) | 2 | (8.7) | ||
| Estrogen receptor: | ||||||||||||
| Positive | 27 | 67.5% | 10 | (71.4) | 17 | (65.4) | 0.912 | 13 | (76.5) | 14 | (60.9) | 0.568 |
| Negative | 7 | 17.5% | 2 | (14.3) | 5 | (19.2) | 2 | (11.8) | 5 | (21.7) | ||
| No available data | 6 | 15.0% | 2 | (14.3) | 4 | (15.4) | 2 | (11.8) | 4 | (17.4) | ||
| Progesterone receptor: | ||||||||||||
| Positive | 25 | 62.5% | 9 | (64.3) | 16 | (61.5) | 0.985 | 11 | (64.7) | 14 | (60.9) | 0.907 |
| Negative | 9 | 22.5% | 3 | (21.4) | 6 | (23.1) | 4 | (23.5) | 5 | (21.7) | ||
| No available data | 6 | 15.0% | 2 | (14.3) | 4 | (15.4) | 2 | (11.8) | 4 | (17.4) | ||
| Her2: | ||||||||||||
| Positive | 10 | 25.0% | 2 | (14.3) | 8 | (30.8) | 0.279 | 2 | (11.8) | 8 | (34.8) | 0.007∗ |
| Negative | 19 | 47.5% | 9 | (64.3) | 10 | (38.5) | 13 | (76.4) | 6 | (26.1) | ||
| No available data | 11 | 27.5% | 3 | (21.4) | 8 | (30.8) | 2 | (11.8) | 9 | (39.1) | ||
| Molecular subtype: | ||||||||||||
| Luminal A | 13 | 32.5% | 7 | (50.0) | 6 | (23.1) | 0.242 | 9 | (52.9) | 4 | (17.4) | 0.049∗ |
| Luminal B | 9 | 22.5% | 2 | (14.3) | 7 | (26.9) | 2 | (11.8) | 7 | (30.4) | ||
| Basal-like | 2 | 5.0% | 1 | (7.1) | 1 | (3.8) | 2 | (11.8) | 0 | (0.0) | ||
| Her2 | 1 | 2.5% | 1 | (7.1) | 0 | (0.0) | 0 | (0.0) | 1 | (4.3) | ||
| Others | 8 | 20.0% | 1 | (7.1) | 7 | (26.9) | 2 | (11.8) | 6 | (26.1) | ||
| No available data | 7 | 17.5% | 2 | (14.3) | 5 | (19.2) | 2 | (11.8) | 5 | (21.7) | ||
∗Chi-square exact test is statistically significant at 95% confidence level.