| BackgroundSomastostatin is an important pituitary hormone, as well as a gastroenteric hormone to regulate a variety of physiologic functions. Somatostatin acts as an inhibitory peptide of various secretory and proliferative reponses. Its effects are mediated by a family of G-protein-coupled receptors (SSTR1-5) that can couple to diverse signal transducton pathways such as inhibition of adenylate cyclase and guanylate cyclase, modulation of ionic conductance channels, and protein dephosphorylation. The five receptors are expressed in various normal and tumor cells, the expression of each receptor being receptor subtype and cell type.Somatostatin acts on various targets including the brain, pituitary, pancreas,gut, adrenals, thyroid, kidney and immune system to regulate a variety of physiological functions. Its actions include inhibition of endocrine and exocrine secretions, modulation of neurotransmission, motor and cognitive functions, inhibition of intestinal motility, absorption of nutrients and ions, vascular contractility and cell proliferation.Compelling evidence has implicated somatostatin in the inhibition of the growth and development of various normal and tumor cells. Thus, somatostatin analogues show antineoplastic activity in a variety of experimental models in vivo and in vitro. Somatostatin receptors are expressed in a large variety of human tumors. However, the clinical implications of the presence of somatostatin receptors in tumors for diagnostic and therapeutic purposes will need to define the physiological role of each receptor subtype expressed in the tumors with respect to its antisecretory and antiproliferative properties.Tumour tissue or cell strain exist ss receptor. At present, non-neuroendocrine rumour tissue had been certified that level of SSTRs are low.More than 50% breast cancer, 40% colorectal cancer present positive sstr, as well as sstrs exist in lymphoma, prostatic cancer, lung cancer and metastases . Singapore national university hospital Loh ks for the first time reported autoradiographic result to detect SSTRs of biopsy specimen of nasopharyngeal carcinoma patients.Found intermediate to high sstr-2 expression.Detecting somatostatin receptor in nasopharyngeal carcinoma might have got definite help treat the tumorous.We study nasopharyngeal carcinoma CNE-2 in vitro, adopt RT-PCR and immunhistochemitry detect changes of relative apoptotic gene and protein, to study relative apoptotic preliminary pathway, and reversion record-polymerase chain reaction (RT-PCR) to detect mRNA expression of SSTRs (1-5) receptor. Treat CNE-2 with somatostatin analogue otreotide, Flow cytometry (FCM) tomeasure cell cycle and apoptosis. 1. methods1.1 Cell culture: human nasopharyngeal carcinoma cell line CNE-2 were supplied by cancer institute of Zhejiang cancer hospital. In contain 10% calf sera, PRMI 1640 intermediate, penicillin and streptomycin each l00u to 37oC, 5% CO2 condition, cells grew and adhibited wall well, per two-three day were generated once.1.2 RT-PCR reaction and measure mRNA series.1.2.1 Extract total RNA, measure concentration of RNA by ultraviolet spectrophotometer, OD 260/280 ratio between 1.7-2.2.1.2.2 RT-PCR reaction: Put out the extractive 3 g RNA, reverse cDNA under 20 l reaction system intermediate.1.2.3 RT-PCR reaction and agarose gel electrophoresis: take forementioned reversion record reaction product to 25 l reactant intermediate to proceed PCR reaction. Manufacture gum. Take 20 l PUC Mix Marker,8 and l0l PCR reaction products respectively, spot sample. Run gel electrify electrophoresis: l00v, 20-30 minutes, observe required amplification fragment by ultraviolet light.1.2.4 RT-PCR amplification primer and measure PCR product series: somatostatin receptor primer were designed and synthesized by shanghai Boya Biology Corporation; PCR products series measured by the corporation.1.3 Flow cytometry analyses cell cycle and detect apoptosis: Take human nasopharyngeal carcinoma CNE-2 cell...
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