Objective: To investigate the expression and signification of B-cell lymphoma/leukemia-2 (bcl-2), bax and ER proteins in epithelial cells in different depth of adenomyosis.
Methods: Expression and correlation of bcl-2, bax and ER proteins were detected by immunohistochemistry staining in 36 adenomyosis cases with superficial (< 1/2 depth of penetration) and deep (≥ 1/2 depth of penetration) ectopic endometrium and eutopic endometrial tissues matched with 30 cases with benign ovarian tumor, uterine septum, pelvic floor dysfunction without adenomyosis as controls.
Results: (1) The expression of ER protein in superficial and deep ectopic tissues (5.04 ± 0.24, 4.91 ± 0.16) were found significantly lower than 6.06 ± 0.36 in eutopic tissues (P < 0.01) and higher than 3.70 ± 0.58 in control group (P < 0.05). There was no statistical difference of ER expression in superficial and deep ectopic endometrium (P > 0.05). (2) The level of bcl-2 protein of 5.6 ± 0.4 in superficial and 6.0 ± 0.3 in deep myometrium of ectopic tissues were significantly higher than 3.6 ± 0.4 in eutopic tissues and 1.9 ± 0.4 in control group (P < 0.01). (3) The level of bax protein of 3.50 ± 0.28 in superficial and 4.80 ± 0.29 in deep myometrial ectopic and 4.43 ± 0.37 in eutopic tissues were significantly lower than 6.18 ± 0.65 in control groups (P < 0.05). The expression of bax in superficial myometrium is significantly lower than deep myometrium in ectopic tissues (P < 0.01). (4) The positive correlation between the expression of ER and bcl-2 protein at superficial myometrium of ectopic tissues (r = 0.720, P < 0.01). And there was no significant correlation with the expression of ER and bax protein at superficial myometrium (r = 0.008, P > 0.05). As well as, there was not significant correlation with the expression of bcl-2, bax and ER protein at deep myometrium (r = 0.089, r = -0.023, P > 0.05). The expression of bax protein in ectopic endometrium was positive correlation with the depth of adenomyosis penetration (r = 0.736, P < 0.01). There was positive correlation between the expression of ER and bcl-2 protein at normal endometrium (r = 0.453, P < 0.05). And there was negative correlation between the expression of ER and bax protein at control group (r = -0.514, P = 0.05).
Conclusion: The bax protein expression of ectopic endometrium in deep adenomyosis was higher than superficial adenomyosis.