Boal J H, Deamond S F, Callahan D E, Bruce S A, Ts'o P O, Kan L S
Department of Chemistry, Catholic University of America, Washington, DC 20017.
Cell Biophys. 1989 Jun;14(3):245-56. doi: 10.1007/BF02797271.
The nuclear magnetic resonance (NMR) parameters, spin-lattice (T1), and spin-spin (T2) relaxation time, are usually longer for neoplastic cells than for normal cells of the same cell type. This has generally been true at low NMR frequencies (less than or equal to 100 MHz) when comparisons have been made between normal and neoplastic cells that have both spent a short time in culture. We have previously demonstrated that although the T1 values of paired normal and neoplastic Syrian hamster (SH) fibroblastic cells in culture are not significantly different when measured at 300 MHz, the 300 MHz T2 values for the neoplastic cells are smaller than those of the normal cells. (Xin et al. (1986), Cell Biophysics 8, 213.) Since treatment of normal diploid cells with polypeptide growth factors or tumor promoters frequently results in reversible expression of neoplasia-associated phenotypes, T1 and T2 were obtained at 300 MHz for treated and untreated SH cells to see if these compounds could also produce smaller 300 MHz T2 values. Secondary culture SH fetal fibroblast cells were treated with epidermal growth factor (EGF), fibroblast growth factor (FGF), phorbol-12,13-didecanoate (PDD) and 4-alpha-phorbol-12,13-didecanoate (4 alpha PDD). Treatment with either growth factor resulted in smaller T2 values, but a statistically significant decrease was not observed for PDD or 4 alpha PDD. The observed reductions in T2 values were correlated with the morphological and growth-stimulatory effects of these compounds on the cells.
核磁共振（NMR）参数，即自旋晶格（T1）和自旋 - 自旋（T2）弛豫时间，对于肿瘤细胞通常比对相同细胞类型的正常细胞更长。当在低NMR频率（小于或等于100 MHz）下对在培养中短期培养的正常细胞和肿瘤细胞进行比较时，情况通常如此。我们之前已经证明，虽然在300 MHz下测量时，培养的成对正常和肿瘤叙利亚仓鼠（SH）成纤维细胞的T1值没有显著差异，但肿瘤细胞的300 MHz T2值小于正常细胞。（Xin等人（1986年），《细胞生物物理学》8，213。）由于用多肽生长因子或肿瘤启动子处理正常二倍体细胞经常导致肿瘤相关表型的可逆表达，因此在300 MHz下获得了处理过和未处理过的SH细胞的T1和T2，以查看这些化合物是否也能产生更小的300 MHz T2值。对传代培养的SH胎儿成纤维细胞用表皮生长因子（EGF）、成纤维细胞生长因子（FGF）、佛波醇 - 12,13 - 十二烷酸酯（PDD）和4 - α - 佛波醇 - 12,13 - 十二烷酸酯（4αPDD）进行处理。用任何一种生长因子处理都会导致T2值减小，但对于PDD或4αPDD未观察到统计学上显著的降低。观察到的T2值降低与这些化合物对细胞的形态学和生长刺激作用相关。
