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BACKGROUND: Thyroid cancer stem cells are essential to the recurrence and metastasis of thyroid carcinoma. Leukemia inhibitory factor receptor (LIFR) shows a downward trend in a variety of malignant tumors, and its overexpression can inhibit the recurrence and metastasis of malignant tumors. OBJECTIVE:To explore the effect of LIFR on the stemness maintenance and lung metastasis of thyroid cancer stem cells in vivo. METHODS: Primary thyroid cancer cells TCLM were isolated from the lung metastases of a metastatic thyroid cancer patient. Serum-free suspension culture was used to form tumor cell balls. Flow cytometry was used to screen CD133+phenotype of metastatic thyroid cancer stem cell subpopulation TCLM-S. The overexpressed recombinant lentiviral plasmid containing LIFR and its negative control containing the empty plasmid were infected into thyroid cancer stem cells TCLM-S at the ratio of virus/cell number=20, and screened with 2.0 mg/L puromycin to construct TCLM-SLIFRand TCLM-Scontrolstem cells which stably expressed LIFR and its control. Real-time quantitative PCR (qRT-PCR) was used to detect the expression of LIFR in TCLM-SLIFRand TCLM-Scontrolstem cells. Flow cytometry was used to detect the percentage of CD133+phenotype cell subsets, western blot assay was used to detect the expression of tumor stemness related factors SOX2, Oct4, Nanog and tumor invasion and metastasis related proteins E-cadherin, matrix metalloproteinase (MMP)-2, MMP-7 in TCLM-SLIFRand TCLM-Scontrol stem cells. TCLM-SLIFRand TCLM-Scontrolstem cells were respectively injected into BALB/c nude mice by tail vein, and the lung metastasis model of thyroid cancer stem cells was constructed. The effect of LIFR overexpression on lung metastasis was observed. RESULTS AND CONCLUSION: Compared with TCLM-Scontrolcells, the expression of LIFR in TCLM-SLIFRcells was significantly increased, the proportion of CD133+phenotype stem cell subsets was significantly decreased, the expression of SOX2, Oct4 and Nanog were significantly decreased, the expression of E-cadherin was significantly increased, and the expression of MMP-2 and MMP-7 was significantly decreased. Moreover, the number of lung metastasis in nude mice given TCLM-SLIFRcells was significantly decreased as compared with those given TCLM-Scontrol cells.To conclude,LIFR overexpression can decrease the stemness and ability of lung metastasis in vivo.
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Purpose To investigate the clinicopathologic characteristics, diagnosis, differential diagnosis and prognosis of malignant solitary fibrous tumor/hemangiopericytoma ( SFT/HPC). Methods Sixteen cases of intracranial malignant SFT/HPC were retrospectively studied. The clinical data, imaging features, histopathological and immunohistochemical characteris-tics were analyzed. Results The 8 male and 8 female patients were between 31 and 71 years of age ( mean 51). The median age was 51 years (range, 31-71 years). 16 malignant SFT/HPC cases were originated from intracalvarium. The imaging features showed intracranial neoplasms with relatively clear surrounding boundaries. Microscopically spindle shaped cells were hypercel-lular, and exhibited≥5 mitoses per 10 HPF. Cytological atypia was mild. The clinicopathologic characteristics included pattern-less growth pattern, storiform or fascicular growth pattern, solita-ry fibrous tumor-like regions and hemangiopericytoma-like re-gions. Tnere were 2 cases with abundant papillary structure and 2 with sarcomatous structure, 2 with focal necrosis, 2 with inva-ded cerebral tissues, and 10 with invaded meninges. Immuno-histochemically, 93. 75% ( 15/16 ) cases were positive for STAT6, with 15/16 showing diffuse staining. 87. 5% (14/16) cases were positive for CD34, with 37. 5% (6/16) showing dif-fuse staining. 81. 25% (13/16) cases were positive for BCL-2. 68. 75% (11/16) cases were positive for CD99. The Ki-67 in-dex ranged from 5% to 40% . Sixteen patients were followed up for 1-64 months, and 7 patients ( 43. 75% ) had recurrences. Conclusion Malignant SFT/HPC shares malignant behaviours. STAT6 is a specific marker for the diagnosis of this tumor. The prognosis of malignant SFT/HPC is related to the extent of tumor excision and long-term follow-up.