Urinary bladder malignant paraganglioma with vertebral metastasis: a case report with literature review / 癌症

Paraganglioma is a rare neuroendocrine neoplasm observed in patients of all ages, with an estimated incidence of 3/1,000,000 population. It has long been recognized that some cases are familial. The majority of these tumors are benign, and the only absolute criterion for malignancy is the presence of metastases at sites where chromaffin tissue is not usually found. Some tumors show gross local invasion and recurrence, which may indeed kill the patient, but this does not necessarily associate with metastatic potential. Here, we report a case of vertebral metastatic paraganglioma that occurred 19 months after the patient had undergone partial cystectomy for urinary bladder paraganglioma. We believe this to be a rarely reported bone metastasis of paraganglioma arising originally within the urinary bladder. In this report, we also provide a summary of the general characteristics of this disease, together with progress in diagnosis, treatment, and prognosis.

Double-mutant dihydrofolate reductase gene transfection into bone marrow cells protects mice from chemotherapy / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the feasibility of transfecting DHFR (human double-mutant dihydrofolate reductase) gene into mouse bone marrow cells and the effect of resistance to high dose MTX chemotherapy.</p><p><b>METHODS</b>After DHFR gene was transfected into mouse bone marrow cells with retroviral vector, the cells were treated with methotrexate (MTX) and then CFU-GM (granulocyte-macrophage colony-forming unit) assay was performed. Peripheral blood leucocytes and platelets, body weight and survival rate were observed. After treatment with high dose MTX, the expression of drug resistance gene was checked by RT-PCR in the transfected bone marrow cells.</p><p><b>RESULTS</b>SFG-F/S-NeoR gene-transfected mice bone marrow cells yielded drug-resistance colonies to MTX (donor mice: 15.8%, recipient mice: 18.0%, control: 0) The peripheral blood leucocytes and platelets, body weight recovered gradually and the survival rate was 83.3% at the 40th day, while 0 in controls in gene transfected mice after large dose MTX treatment. RT-PCR of transgenic mouse marrow cells showed the band of F/S gene (400 bp).</p><p><b>CONCLUSION</b>DHFR gene can not only be integrated and expressed in bone marrow cells but also improve their drug-resistence to MTX.</p>