Souttou B, Hamelin R, Crépin M
Institut d'Oncologie Cellulaire et Moléculaire Humaine, Bobigny, France.
Cell Growth Differ. 1994 Jun;5(6):615-23.
HBL100 is a human breast epithelial cell line which has been immortalized by the defective genome of SV40 but which is not tumorigenic in nude mice. Growth experiments in defined serum-free and protein-free media revealed its ability to grow without exogenous supply of serum growth factors. Addition of heparin to the serum-free medium increased its growth rate, suggesting the release of heparin-binding autocrine growth factor(s) in the culture medium. HBL100-conditioned medium was mitogenic for HEMG (human embryonic mammary gland) and CCL39 fibroblasts. Western blot analysis of growth factors revealed the presence of the M(r) 18,000, 22,000 and 24,000 forms of basic fibroblast growth factor (bFGF or FGF2) both in HBL100 cell extracts partially purified on heparin-Sepharose beads and in concentrated conditioned medium. Northern blot analysis of HBL100 RNA demonstrated the synthesis of 7-, 3.7-, and 1.8-kilobase (kb) FGF2-specific mRNAs by these cells. Anti-FGF2 neutralizing IgG inhibited HBL100 growth in serum-free medium in a dose-dependent manner. Affinity cross-linking of 125I-FGF2 to the HBL100 cell surface revealed an FGF receptor of 130 kDa. Taken together, these results suggest that FGF2 may be implicated as an autocrine growth factor in the early events leading to neoplastic transformation of human breast epithelial cells.
HBL100是一种人乳腺上皮细胞系，它通过SV40的缺陷基因组实现了永生化，但在裸鼠中不具有致瘤性。在限定的无血清和无蛋白培养基中进行的生长实验表明，它能够在不额外供应血清生长因子的情况下生长。向无血清培养基中添加肝素可提高其生长速率，这表明培养基中释放了肝素结合自分泌生长因子。HBL100条件培养基对HEMG（人胚胎乳腺）和CCL39成纤维细胞具有促有丝分裂作用。对生长因子进行的蛋白质印迹分析显示，在经肝素-琼脂糖珠部分纯化的HBL100细胞提取物以及浓缩的条件培养基中均存在分子量为18,000、22,000和24,000的碱性成纤维细胞生长因子（bFGF或FGF2）形式。对HBL100 RNA进行的Northern印迹分析表明，这些细胞可合成7、3.7和1.8千碱基（kb）的FGF2特异性mRNA。抗FGF2中和性IgG以剂量依赖性方式抑制HBL100在无血清培养基中的生长。125I-FGF2与HBL100细胞表面的亲和交联显示出一种130 kDa的FGF受体。综上所述，这些结果表明FGF2可能作为一种自分泌生长因子参与导致人乳腺上皮细胞肿瘤转化的早期事件。
