Langeland Marthinsen Anne Beate, Dybdahl Wanderås Anne, Lundgren Steinar, Strickert Trond, Hundal Elisabeth, Graff Bjørn Anton
Department of Oncology, St. Olavs Hospital, University Hospital of Trondheim, 7006 Trondheim, Norway.
Oncol Rep. 2002 Mar-Apr;9(2):397-403.
Different growth factors are supposed to be involved in evolution of breast cancer. Radiation therapy is used in treatment of breast cancer patients, and the possible relationships between the influence of growth factors on cells and their radiation sensitivity are therefore of interest. Cell growth and radiation sensitivity of the human oestrogen and progesterone receptor positive cell line T-47D were investigated following exposure to the growth factors IGF-1, TGF-alpha and TGF-beta. Experiments were done with standard medium and in growth factor defined medium. Changes in cell cycle distribution were investigated by flow cytometry. The cell growth was significantly decreased by removal of growth factors in the culture medium, an effect which partly could be reversed by supplementation of growth factors. The growth factors decreased the cellular doubling time in standard medium, but to a smaller extent than seen in growth factor defined medium. The radiation sensitivity and plating efficiency were slightly affected by growth factor defined versus standard growth conditions. Additional growth factor exposure was able to some extent to change the radiation sensitivity, mainly by effects due to changes in repair of sublethal damage. Only minor changes were seen in phase distribution of these cells. Cellular growth was dependent on presence of different growth factors, and changes in growth factor conditions greatly influenced the cellular doubling time in vitro. Corresponding changes in radiation sensitivity were minor for doses relevant for radiation therapy.
不同的生长因子被认为与乳腺癌的演变有关。放射治疗用于乳腺癌患者的治疗，因此生长因子对细胞的影响与其放射敏感性之间的可能关系备受关注。在暴露于生长因子IGF-1、TGF-α和TGF-β后，研究了人雌激素和孕激素受体阳性细胞系T-47D的细胞生长和放射敏感性。实验在标准培养基和生长因子限定培养基中进行。通过流式细胞术研究细胞周期分布的变化。去除培养基中的生长因子会显著降低细胞生长，补充生长因子可部分逆转这一效应。生长因子缩短了标准培养基中细胞的倍增时间，但程度小于生长因子限定培养基中的情况。与标准生长条件相比，生长因子限定条件对放射敏感性和接种效率的影响较小。额外的生长因子暴露在一定程度上能够改变放射敏感性，主要是通过对亚致死损伤修复变化的影响。这些细胞的周期分布仅出现微小变化。细胞生长依赖于不同生长因子的存在，生长因子条件的变化极大地影响了体外细胞的倍增时间。对于放射治疗相关剂量，放射敏感性的相应变化较小。
