Characterization of Cyclin D2 Expression in Human Endometrium

Abstract

Objective: This study was undertaken to investigate cyclin D2 mRNA and protein expression in human endometrium during the menstrual cycle.

Methods: Endometrial samples were obtained from 15 premenopausal nonpregnant women who had hysterectomies for benign gynecologic reasons. They were divided into the following five groups according to histologic dating: early proliferative (n = 3), mid to late proliferative (n = 3), early secretory (n = 3), mid secretory (n = 3), and late secretory (n = 3). Cyclin D2 mRNA and protein expression were analyzed using reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemistry.

Results: Cyclin D2 mRNA and protein were expressed in human endometrial tissue throughout the menstrual cycle. Cyclin D2 mRNA and protein expression of proliferative phase endometrium were significantly higher than those of secretory phase endometrium (P < .05). The staining intensity of cyclin D2 in proliferative phase endometrium was higher than that in secretory phase (P < .05). Cyclin D2 mRNA level showed good correlation with cyclin D2 protein level (R = 0.579, P < .03), and cyclin D2 protein also showed good correlation with immunohistochemical staining intensity (R = 0.562, P < .03).

Conclusion: Cyclin D2 was expressed in human endometrium throughout the menstrual cycle. Cyclin D2 mRNA and protein were expressed at high levels in proliferative phase endometrium, especially in the early proliferative phase, and then decreased in the secretory phase.

Keywords

Cyclin D2 human endometrium menstrual cycle

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References

1. Sherr CJ . G1 progression: Cycling on cue. Cell 1994;79:551-555.

2. Robker RL , Richards JS . Hormone-induced proliferation and differentiation of granulose cells: A coordinated balance of the cell cyclin regulators cyclin D2 and p27KIP1. Mol Endocrinol 1998;12:924-940.

3. Choi DS , Lee EY , Yoon SR , Hwang SS , Yoon BK , Lee JH . Clinical correlation of cyclin D2 mRNA expression in human luteinized granulosa cells. J Assist Reprod Genet 2000;17:574-579.

4. Noyes RW , Hertig AT , Rock J . Dating the endometrial biopsy. Fertil Steril 1950;1:3-25.

5. Grana X , Reddy EP . Cell cycle control in mammalian cells: Role of cyclins, cyclin-dependent kinases, growth suppressor genes and cyclin-dependent kinase inhibitors. Oncogene 1995;11:211-219.

6. Hunter T , Pines F . Cyclins and cancer II: Cycin D and cdk inhibitors come of age. Cell 1994;79:573-582.

7. Baldin V , Lukas J , Marcote MJ , Pagano M , Draetta G . Cyclin D1 is a nuclear protein required for cell cycle progression in G1. Genes Dev 1993;7:812-821.

8. Quelle DE , Ashmun RA , Shurtleff SA , Kato JY , Bar-Sagi D , Roussel MF , Sherr CJ . Overexpression of mouse D-type cyclins accelerates G1 phase in rodent fibroblasts. Genes Dev 1993;7:1559-1571.

9. Richards JS . Hormonal control of follicular growth and maturation in mammals. In: Jones RE , ed. The vertebrate ovary: Comparative biology and evolution. New York: Plenum Press, 1978:331-360.

10.

10. Richards JS . Maturation of ovarian follicles: Action and interactions of pituitary and ovarian hormones on follicular cell differentiation. Physiol Rev 1980;60:51-89.

11.

11. Uilenbroek JT , Richards JS . Ovarian follicular development during the rat oestrous cycle: Gonadotropin receptors and follicular responsiveness. Biol Reprod 1979;20:1159-1165.

12.

12. Brooks AR , Shiffman D , Chan CS , Brooks EE , Milner PG . Functional analysis of the human cyclin D2 and cyclin D3 promotors. J Biol Chem 1996;271:9090-9099.

13.

13. Shiozawa T , Li SF , Nakayama K , Nikaido T , Fujii S . Relationship between the expression of cyclins/cyclin-dependent kinases and sex-steroid receptors/Ki67 in normal human endometrial glands and stroma during the menstrual cycle. Mol Hum Reprod 1996;2:745-752.