Effect of hematoporphyrin derivative (HPD) plus light on transcription activity in the nucleus
To elucidate the mechanism of photodynamic damage of cells, the effect of HPD plus light on transcriptional ectivity in the mucleus isolate from the normal rat liver was studiedin vitor by3H- UTP incorporation into RNA. Measurements of fluorescence spectrum showed that HPD was bound to the nucleus and its fluorescence intensity increased with the increase of HPD concentration. The experimental results indicated that no changes could be observed when either HPD or light was used alone. Whereas the nuclear transcription activity was found to be inhibited significantly by both HPD and light treatment, and the degree of inhibition was dependent on the HPD concentration and the time of exposure to light. After treatment by 3 µg/ml HPD, the inhibition rate of the nuclear transcription activity was 23%, 45%, 69%, 80% and 90%, respectively for light exposure of 2, 5, 10, 20 and 30 minutes. Our results suggested that dose-dependent decreases in the nuclear transcription activity, and marked inhibition of the activity was found in the range from 3 to 7 µg/ml HPD following exposure to light.
KeywordsFluorescence Spectrum Transcription Activity Light Treatment Hematoporphyrin Hematoporphyrin Derivative
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
Boye E, et al. The Photodynamic effect of hematoporphyrin on DNA. Photochem Photobiol 1980; 31:223.CrossRefGoogle Scholar
Evensen JF, et al. Photodynamic action and chromosomal damage: A comparison of haematoporphyrin derivative (HPD) and light with Xirradiation. Br J Cancer 1982; 45: 456.PubMedGoogle Scholar
Moan J, et al. DNA single-strand break and sister chromatid exchanges induced by treatment with hematoporphyfin and light or by X-rays in human NHIK 3025 cells. Cancer Res 1980; 40:2915.PubMedGoogle Scholar
Salet C, et al. Hematoporphyrin and hematoporphyrin-derivative photosensitization of mitochondria. Biochimie 1986; 68:865.PubMedCrossRefGoogle Scholar
1988; 10(5):349.Google Scholar
1989; 11(1):22.Google Scholar
1981; 13(5):523.Google Scholar
Burton KAA. Study of the conditions and mechanism of the diphenylamine reaction for the colorimetric estimation of deoxyri-bonucleic acid. Biochem J 1956; 62:315.PubMedGoogle Scholar
Bugelski PJ, et al. Autoradiographic distribution of haematoporphyrin deriva-tive in normal and tumor tissue of the mouse. Cancer Res 1981; 41:4606.PubMedGoogle Scholar
Dougherty TT, et al. Photoradiation therapy for the treatment of malignant tumors. Cancer res 1978; 38(2):628.Google Scholar
1983; 60(6):336.Google Scholar
© Chinese Journal Of Cancer Research 1992