Immunohistochemical study of glutathione S-transferase in preneoplastic and neoplastic lesions of human urinary bladder / 대한비뇨기과학회지

Glutathione S-transferase(GST) is a family of enzymes which plays an important role in cellular detoxification by catalyzing the conjugation of electrophilic xenobiotics with glutathione and recently have been shown to be closely associated with chemical carcinogenesis and resistance to cytotoxic drugs in several types of malienancies. However, it remains ill-defined about the role of GST in bladder tumor. Herein we performed immunohistochemical study using polyclonal antibody directed against acidic(pi form) and basic GST and analyzed the intensity(0-3+) and proportion(grade 1-4) of staining in bladder specimens from 50 patients with bladder tumor and from 10 normal controls. On GST-pi immunohistochemical stain, normal bladder mucosa was stained only focally and in low intensity, whereas the staining intensity and proportion were significantly increased in transitional cell hyperplasia, dysplasia /carcinoma in situ(CIS), and overt carcinoma (p<0.05). The staining intensity and proportion of GST-pi were significantly lower in invasive and high grade (III, IV/VI) transitional cell carcinoma(TCC) compared to superficial and low grade TCC (p<0.001). There were no significant differences in the intensity and proportion of GST-pi staining between superficial bladder TCC which recurred and which did not recur after prophylactic intravesical chemotherapy. On basic GST immunohistochemical stain, normal bladder as well as preneoplastic and neoplastic lesions or the bladder showed only focal and low intensity staining. These results suggest that GST-pi may be a marker of preneoplatic lesions and low grade, superficial TCC or bladder and that invasive and high grade TCC of bladder may have another cellular deloxilication mechanism different from GST. GST may not be the major mechanism of drug resistance in superficial bladder TCC. The role or basic GST in normal bladder as well as in bladder TCC is in doubt.

Malignant Choroid Plexus Tumor in an Infant

A 42 day-old male infant visited to our emergency room with chief complaints of convulsion. Prenatal and birth histories were unremarkable. The patient appeared well except persistent jaundice and had no signs of increased intracranial pressure. The head circumference at birth was not measured. The head circumference at 42 days was 39cm(50th percnntile) At the age of 42 days, tonic convulsion developed suddenly and soon fell into coma. The patient died, 20 hours after arrival. Postmortem examiation revealed a large necrotic tumor mass in the left lateral ventricle of the cerebral hemispheres. The tumor growths were histologically composed of partly papillary but most undifferentiated carcinoma arising from the choroid plexus of the left lateral ventricle. In addition to celluar anaplasia many mitoses were observed. The tumor masses invaded periventricular while matter and also extended to subarachnoid space of the cerebral and cerebellar hemispheres. The central part of the tumor was undergoing necrosis and massive hemorrhage which extended into surrounding brain parenchyme.