放疗后体内31P核磁共振波谱测量、肿瘤大小、缺氧分数与细胞存活之间的相关性。

Correlations between in vivo 31P NMR spectroscopy measurements, tumor size, hypoxic fraction and cell survival after radiotherapy.

作者信息

Fu K K, Wendland M F, Iyer S B, Lam K N, Engeseth H, James T L

机构信息

Department of Radiation Oncology, University of California, San Francisco 94143.

出版信息

Int J Radiat Oncol Biol Phys. 1990 Jun;18(6):1341-50. doi: 10.1016/0360-3016(90)90307-6.

DOI:10.1016/0360-3016(90)90307-6

PMID:2370183

Abstract

Phosphorus metabolite levels were measured non-invasively using 31P magnetic resonance spectroscopy (MRS) in SCCVII/SF tumors, subcutaneously transplanted into the legs of unanesthetized C3Hf/Sed mice. Shortly after MRS measurements, tumors were irradiated with a single dose of 20 Gy, and cell survival and radiobiologic hypoxic fraction were determined with an in vitro cloning assay. Significant correlations were found between tumor size and surviving fraction, hypoxic fraction, pH, and phosphorus metabolite ratios. With increase of tumor size, surviving fraction and hypoxic fraction both increased, the ratios of inorganic phosphate and phosphomonoesters to nucleoside triphosphates (Pi/NTP and PME/NTP, respectively) and inorganic phosphate to phosphocreatine (Pi/PCr) increased and pH decreased. However, considerable heterogeneity of MRS spectral parameters, even in tumors of similar size, precluded accurate prediction of hypoxic fraction and cell survival after radiotherapy.

摘要

在未麻醉的C3Hf/Sed小鼠腿部皮下移植的SCCVII/SF肿瘤中，使用31P磁共振波谱（MRS）对磷代谢物水平进行无创测量。MRS测量后不久，肿瘤接受20 Gy的单次照射，并通过体外克隆试验测定细胞存活率和放射生物学缺氧分数。发现肿瘤大小与存活分数、缺氧分数、pH值和磷代谢物比率之间存在显著相关性。随着肿瘤大小的增加，存活分数和缺氧分数均增加，无机磷酸盐与磷酸单酯与核苷三磷酸的比率（分别为Pi/NTP和PME/NTP）以及无机磷酸盐与磷酸肌酸的比率（Pi/PCr）增加，pH值降低。然而，即使在大小相似的肿瘤中，MRS光谱参数也存在相当大的异质性，这使得放疗后缺氧分数和细胞存活率的准确预测变得不可能。