Study On Trace Element Levels And Chemical Species In Malignant And Paramalignat Tissues

In this thesis, the levels of 12 trace elements in malignant and paranialignant tissues of 6 sorts cancer patients (37patients), and the factors affecting the distribution of these trace elements between malignant and paramalignant tissues were studied. The results showed that the distribution of these trace elements had organ-specificity, and levels of some trace elements were correlated with cancer to some extent, but the distribution were affected by age, gender, nicotine (smoking), ethanol (drinking) and interactions among trace elements. Therefore, the conclusion that the abundance or absence of trace elements had necessary connexion with cancer could not be drawn from the difference of trace elements between malignant and paramalignant tissues. The study of copper chemical species showed a significant difference between malignant and paramalignant tissues. Copper chemical species in malignant colon tissues were little, and copper was combined with proteins, whereas copper in paramalignant colon tissues had a variety of chemical species whose ultraviolet absorption was weak. Copper chemical species in malignant and paramalignant liver tissues also differed significantly. In paramaligmant liver tissues, copper existed mainly in four species whose MWs were between 3000 Da and 80000Da, with little ultraviolet absorption. Copper in malignant liver tissues had two sorts of chemical species, one had absorption at 280nm, the other had no absorption but a MW bigger than 80000Da. The study also showed that part of copper and cadmium existed in paramalignant liver tissues together. Part of Cadmium combined with biomolecules with higher molecular weight (>80000Da) in paramalignant liver tissues was transformed into biomolecules with lesser molecular weight (3000-80000Da). According to these, not only copper but also cadmium had chemical specie transformation during the occurrence and development of cancer. This paper was very important in revealing the action mechanism of trace elements in the occurrence of cancer.