Adenosine dialdehyde and nitrous oxide induce HL-60 differentiation

Adenosine dialdehyde and nitrous oxide, specific S-adeno- sylhomocysteine hydrolase and methionine synthetase inhibitors, respectively, induced differentiation of the human promyelocytic cell line HL-60. Their effect did not appear to be mediated through changes in transmethylation or decreased S-adenosylmethionine synthesis because (1) there was little correlation between the concentrations of adenosine dialdehyde that induced differentiation and those that changed the ratio of the intracellular concentrations of S- adenosylmethionine to S-adenosylhomocysteine, and (2) inhibition of methionine adenosyltransferase by cycloleucine did not induce differentiation. The differentiation induced by adenosine dialdehyde was prevented by homocysteine and that by nitrous oxide was inversely related to the medium methionine concentration. This suggested that differentiation was secondary to decreased methionine synthesis.     

Primary site as a prognostic variable for children with pelvic soft tissue sarcomas

From 1974 to 1983 we treated 16 children between 1 and 16 years old for soft tissue sarcoma arising in the pelvis, bladder or prostate. An incisional biopsy was obtained in every patient. Each child then was treated with a combination chemotherapy program, incorporating vincristine, actinomycin D and cyclophosphamide with or without doxorubicin, cis-platinum and etoposide. Of the 16 patients 13 (81 per cent) also received radiation therapy. In 8 children with urinary obstruction or hematuria sarcomas arose in the bladder or bladder-prostate region, including 7 who had localized tumors and 1 who had lung metastases at diagnosis. The median tumor diameter in these patients was 5 cm. Of these 8 patients 3 eventually required total cystectomy and prostatectomy to eradicate persistent local tumor, and 6 are alive and remain free of recurrent sarcoma for 1 to 9 years after initiation of therapy. The 8 other children had a pelvic mass at diagnosis, which arose adjacent to but outside of the bladder or prostate, and 2 had lung metastases at diagnosis. The median tumor diameter in these patients was 15 cm. Only 3 of these 8 children are alive and remain free of sarcoma for 1 to 8 years after initiation of therapy. In only 1 of these children was complete tumor excision ever possible despite the use of local radiation therapy and aggressive chemotherapy. Sarcomas arising in the bladder-prostate region are found when relatively small, perhaps because they soon produce overt signs, and they appear to have a better prognosis than those arising in the retroperitoneum-pelvis outside the bladder. Better treatment strategies are needed for the latter group of tumors that often are locally uncontrollable.     

Malignant Rhabdoid Tumor Presenting as a Hemangioma

Abstract: Malignant rhabdoid tumor is a rare and highly aggressive malignancy of unknown etiology. We report a primary cutaneous rhabdoid tumor on the upper back of a newborn. It was initially diagnosed as a hemangioma clinically, and that diagnosis was supported by radiologic studies, including magnetic resonance imaging. However, detailed investigation with light microscopy, immunohistochemistry, and electron microscopy enabled us to make a diagnosis of rhabdoid tumor. This is the seventh reported case of rhabdoid tumor with primary cutaneous involvement.