INSULIN-LIKE GROWTH-FACTOR-T PROMOTES LEIOMYOMA CELL-GROWTH IN-VITRO

OBJECTIVE: Our purpose was to determine whether insulin-like growth fa ctors I and II preferentially stimulate uterine leiomyoma cells versus myometrial cells in monolayer culture. STUDY DESIGN: Leiomyomas and n ormal myometrium were obtained at hysterectomy from five premenopausal women. Specimens were enzymatically digested for use in primary monol ayer cell cultures. By use of serum-free media, insulin-like growth fa ctor I or II was added in 1, 10, and 100 ng/ml concentrations to both cell types with the patient serving as her own control. Cell number, p rolactin production, and proliferative index values were measured on d ay 15 of cell culture. RESULTS: Significant increases in cell number w ere found in the leiomyoma cultures (p < 0.05) treated with 10 and 100 ng/ml insulin-like growth factors I but not with insulin-like growth factors II. Neither factor exerted a stimulatory effect on myometrial cells. CONCLUSION: Insulin-like growth factors I preferentially stimul ates leiomyoma cells in monolayer culture. These results suggest an au tocrine-paracrine role in vivo for this factor in conjunction with gon adal steroids in promoting leiomyoma growth.