[Expression of CD200 and INSM1 in gastrointestinal and pancreatic neuroendocrine neoplasms and its diagnostic values]

Objective: To investigate the expression and diagnostic values of CD200 and insulinoma associated protein 1 (INSM1) in gastrointestinal and pancreatic neuroendocrine neoplasm (GIP-NEN). Methods: The expression of CD200, INSM1, Syn and CgA was detected in 69 cases of GIP-NEN, 66 cases of gastrointestinal and pancreatic non-neuroendocrine neoplasm (GIP-nonNEN) and 16 cases of metastatic neuroendocrine neoplasm by immunohistochemistry, to compare the values of CD200, INSM1, Syn, CgA and their combinations in diagnosing GIP-NEN. Receiver operating characteristics (ROC) curve was used. Results: The immunoreactivity of CD200 was present in the cytoplasma and/or membrane of the neoplasms cells, the positive expression rates in GIP-NEN and GIP-nonNEN were significantly different (P<0.01). The sensitivity and specificity of CD200 for diagnosing GIP-NEN were 95.7% and 78.8%, respectively. There was significant difference of the positive rates of CD200 between neuroendocrine tumor and neuroendocrine carcinoma (P=0.05). The immunoreactivity of INSM1 was present in the nuclei of neoplasms cells. The positive expression rates in GIP-NEN and GIP-nonNEN were significantly different (P<0.01). The sensitivity and specificity of INSM1 for diagnosis of GIP-NEN were 85.5% and 95.5%, respectively. There were also significantly different positive rates of INSM1 between neuroendocrine tumor and neuroendocrine carcinoma, as well as between G1 and G3 neuroendocrine tumors (P<0.05). There was no difference in the area under ROC curve (AUC) of single stain of CD200, INSM1, Syn or CgA (0.857, 0.907, 0.890 and 0.833, respectively, P>0.05). The sensitivity of combined CD200+INSM1 stains for diagnosing GIP-NEN was significantly higher than that of Syn+CgA (85.5% vs. 63.8%, P<0.05). The AUC of two combinations were 0.962 and 0.925, respectively, which were not statistically different (P>0.05). Conclusions: CD200 and INSM1 are two novel markers of neuroendocrine neoplasm, which aid to diagnosis for GIP-NEN and exclude its mimickers. They are associated with tumor grades. Combining both as an immunohistochemical panel shows high sensitivity and specificity. Thus, the combined panel can be utilized as useful supplement for Syn and CgA.

[The stimulation of human pulmonary artery endothelial cells by cigarette smoke extract contributed to cell senescence and induced human pulmonary artery smooth cell migration]

Objective: To observe the senescent effect of human pulmonary arterial endothelial cells (HPAEC) stimulated by cigarette smoke extract (CSE) and the effect of secretion of senescent cells on human pulmonary arterial smooth muscles cell (HPASMC) proliferation and migration. Methods: HPAEC was treated with different concentrations of CSE in vitro and cell proliferation was determined by CCK8, senescence cells analyzed by detecting the β-gal activity, and the senescent proteins of cells measured by Western blot. The concentration of senescence-associated secretory phenotype (SASP) was detected by ELISA and the expression of MCP-1 and TGF-β1 was measured by Real-time PCR. The number of the proliferated cells was measured by Transwell assay and immunoflurescence. Results: The HPAEC was aging with the stimulation concentration of CSE increasing and the stimulation time prolonging (P<0.05). Western blot indicated that the senescent associated protein p53 or p21 increased markedly after 48 h and 72 h CSE-exposure (n=3, P<0.05). The SA-β-Gal staining showed that the number of senescent cells increased as the exposure time prolonged. Compared with the control group, cell viability of 48 h group(1.8±0.1) and 72 h group (1.8±0.1) decreased significantly. The flow cytometry showed a significant difference between the CSE group(14.1±1.2) and the control group(28.5±1.8) in S phase(P<0.01), indicating cell cycle arrest. The SASP was increasing as the CSE-exposure prolonged. Compared with the control group(177±39), the 48 h group(460±43) and the 72 h group(609±64) showed a marked increase in MCP-1(P<0.05). For TGF-β1, it had a same tendency and a significant difference between the control group(121±18) and the 48 h group(413±32) or 72 h group(606±67, both P<0.05). In the meantime, the bFGF increased after 48 h stimulation(291±13, P<0.05). Besides MCP-1, TGF-β1 showed a significant difference between the control group and the 72 h CSE-exposure group (P<0.01). Premature cells could secrete SASP which induced HPASMC proliferation. After different times of conditioned medium stimulation, HPASMC proliferated especially at 72 h(P<0.05) . The immnoflorescence and Transwell assay confirmed this finding. Conclusion: CSE could induce senescence of HPAEC and SASP production which improved HPASMC proliferation and migration.