[Clinicopathologic features of papillary tumors of the pineal region].

OBJECTIVE: To study the clinicopathologic features of papillary tumor of the pineal region (PTPR). METHOD: Three hundred and eighty six cases of pineal region and posterior third ventricle tumors, two newborn and two adult pineal glands were analyzed by HE, PAS and immunohistochemistry of 16 antibodies (EnVision method). RESULTS: Five cases of PTPR were diagnosed with mixed papillary features and densely cellular areas, and included one recurrent case. In the papillary areas, the vessels were lined by one or several layers of cuboidal/columnar cells; the vessel wall was hyalinized. In the densely cellular areas, sheets or nests of tumor cells were seen. The tumor cells of these five cases were immunoreactive to CK, CK8/18, synaptophysin, MAP2, nestin, S-100, and vimentin. Four cases were immunoreactive to NSE and CgA; and 2 cases were immunoreactive to NF. All five cases were negative for EMA, CK5/6, CEA, and NeuN. Ki-67 labeling index ranged from 1% to 6%.Three patients were alive, and the recurrent one died. CONCLUSIONS: PTPR occurs in patients with over a wide age range, from children to adults, and is more commonly found in male than female. PTPR is composed of both papillary and solid areas, characterized by epithelial cytology, and needs to be differentiated from ependymoma. PTPR may originate from the specialized ependymocytes of the subcommissural organ. The prognostic factors are early diagnosis, complete surgical resection and radiotherapy.

[Identification of bone marrow stromal cells and expression of tyrosine hydroxylase gene in them].

The study is to establish the method of isolation and identification of bone marrow stromal cells and to investigate the ability of bone marrow stromal cells to accept and express TH gene. Cells were isolated by a density gradient (lymphocytes separation) and identified by BrdU labeling and fluorescence-activated cell sorting (FACS) technology using CD11b, CD45 and CD90 antibodies. TH and lacZ gene were transfected to rBMSCs with an adeno-associated virus vector. The results showed that most tightly adherent cells in the primary culture were fibroblast-like and formed foci of two to four cells. The cells in the foci remained dormant for 2 to 4 days and then began to multiply rapidly. After several passages, the adherent cells became more uniformly spindle-shaped in appearance. BrdU, indicating that BMSCs replicate actively, labeled about 74.9% of cultured cells. Data from FACS showed that about 75% of isolated cells were CD90(+)/CD45(-)/CD11b(-), which is the marker of bone marrow stromal cells. The efficiency of TH gene transfection was about 75%. BMSCs could readily be genetically engineered and could be useful delivery targets of gene therapy for Parkinson's disease.

[Gene therapy of tyrosine hydroxylase, aromatic L-amino acid decarboxylase, and GTP cyclohydrolase genes in rat model of Parkinson's disease].

OBJECTIVE: To detect the expression and function of enzyme genes involved in biosynthetic pathway for dopamine in vitro and assess their effect in rat model of Parkinson's disease. METHODS: Cos7 cells were transfected with separate adeno-associated virus (AAV) expressing tyrosine hydroxylase (TH) gene, aromatic L-amino acid decarboxylase (AADC) gene and GTP cyclohydrolase I (GCH-I) gene. The expression and function of the three genes were detected by methods of immunohistochemistry, in situ hybridization and high performance liquid chromatograph and electrochemical detection (HPLC-ECD). Gene engineered cells were sequentially transplanted into the striatum of 6-hydroxy-dopamine-leisioned Parkinsonian rat by stereotaxic instrastriatal injection. The asymmetric rotations of these rats after apomorphine administration were detected every week after transplantation. 10 weeks after grafting, the animals were sacrificed and the dopamine produced in the striatum was detected by HPLC-ECD. RESULTS: In vitro experiments showed that the three genes were high expressed in Cos7 cells. When Cos7 cells expressing TH, AADC and GCH-I were cocultured, they produced large amount of dopamine in the condition of existance of L-tyrosine. Furthermore, triple genes therapy resulted in greater dopamine production in the striatum of Parkinsonian rats and improved the rotational behavior of the rats more efficiently than did single gene therapy. However, the production of dopamine in the rats with triple genes therapy is no more than double genes therapy. CONCLUSION: For gene therapy in Parkinson's disease, the amount of target genes to be used should be determined by the level of doperminergic neurons damaged. In the present study, the efficiency of multiple genes therapy is significantly better than that of single gene therapy.