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51.
AIM: To investigate the mechanism of the radiosensitizing effect of maximum non-cytotoxic doses of tetrandrine (Tet) on nasopharyngeal carcinoma cell lines CNE1 and CNE2.METHODS: The cells were treated with ma-ximum non-cytotoxic doses of Tet (for CNE1 cells at 1.5 μmol/L and for CNE2 cells at 1.8 μmol/L), irradiation at 4 Gy, or combination of irradiation and maximum non-cytotoxic doses of Tet. The cell cycle distribution was analyzed by flow cytometry. The protein levels of γ-H2AX, cleaved caspase-3, p-CDC25C, CDK1, p-CDK1, cyclin B1, ERK and p-ERK were determined by Western blot.RESULTS: The expression of γ-H2AX was increased in CNE1 cells and CNE2 cells after combined treatment with irradiation and maximum non-cytotoxic doses of Tet. The percentages of CNE1 cells and CNE2 cells at G2/M phase in irradiation group were (18.09±0.42)% and (18.48±1.32)%, respectively, which were decreased to (15.88±1.04)% and (13.80±0.82)% in combined treatment group, respectively (P<0.05). Combined treatment enhanced the increase in the protein level of cleaved caspase-3 caused by irradiation. The protein levels of p-CDC25C and p-CDK1 were increased in a dose-dependent manner by Tet treatment (P<0.05), while the expression of CDK1 showed no difference among different doses of Tet treatments. The protein levels of p-CDC25C, p-CDK1 and CDK1 showed no difference after the treatment with maximum non-cytotoxic doses of Tet. The combined treatment with irradiation and the maximum non-cytotoxic doses of Tet decreased the protein levels of p-CDC25C and p-CDK1 (P<0.05), increased the expression of cyclin B1, and had no influence on the expression of CDK1 (P<0.05). The combined treatment resulted in an increase in the protein level of p-ERK1 (P<0.05).CONCLUSION: The maximum non-cytotoxic doses of Tet enhance the DNA damage and apoptosis in CNE1 cells and CNE2 cells caused by irradiation, and the mechanism might be associated with ending of G2/M arrest via activation of ERK/CDC25C/CDK1/cyclin B1 pathways.  相似文献   
52.
本文对6例乳腺癌的肿瘤血供研究发现主要供血动脉是胸廓外侧动脉,而非肩胛下动脉和胸廓内动脉。提出行动脉灌注化疗时,不宜只行胸廓内动脉灌注,而应扩大范围,包括上述三支动脉。同时对6例乳腺癌术前灌注化疗的效果作了观察。  相似文献   
53.
Eight dogs with a firm, nonpainful swelling in the ventral laryngeal region and with a final diagnosis of ectopic thyroid carcinoma were investigated by Computed Tomography (CT) at six different institutions. Computed Tomography findings were reviewed, focusing on lesion volume, shape, margins, relationship with surrounding structures and adjacent vessels, attenuation characteristics, and presence of metastases. Ectopic thyroid carcinomas were seen as oval‐to‐bilobed masses centered on the basihyoid bone with associated bone lysis, highly vascularized capsules with central poorly contrast enhancing areas. In all cases there was laryngeal wall infiltration, in two dogs invasion of the laryngeal lumen and in one case invasion of the ventral muscular and subcutaneous plane. Metastases were found in retropharyngeal lymph nodes (three cases) and in the lung (two cases). Ectopic thyroid carcinoma should be considered in the differential diagnosis when a mass in the basihyoid region is present. Described CT features may be typical for ectopic thyroid neoplasia and could be used to help decide the therapeutic plan.  相似文献   
54.
Objective  Local photodynamic therapy (PDT) is a novel cancer therapy in veterinary ophthalmology. A prospective pilot study seeking to demonstrate proof of principle and safety for the treatment of equine periocular squamous cell carcinoma (PSCC) was therefore conducted. We hypothesized that surgical excision with adjunctive local PDT is an effective and safe treatment for equine PSCC.
Procedures  Nine horses (10 eyes) with PSCC were treated with surgical resection, local infiltration of resulting wound beds with 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH) and irradiation with 665-nm wavelength diode laser. Regular follow-up ophthalmic examinations were performed.
Results  Surgical resection and PDT yielded disease-free intervals of 25–68 months in our study horses as of January, 2008. These results were obtained following a single treatment in seven horses and two treatments in one horse. In one horse, carcinoma in situ developed 2.5 months after partial surgical excision and PDT, requiring local excision under standing sedation.
Conclusions  Preliminary results suggest that surgical resection and adjunctive local PDT is a safe and effective novel treatment for PSCC in horses. More research is needed before PDT for the treatment of equine PSCC can be adequately compared with other current modalities. Important to future investigations regarding PDT, tumor recurrence rate, length of hospitalization, number of treatment episodes required to effect tumor remission, and total treatment costs should be examined in a controlled manner. Our present results and experiences suggest that this treatment may be useful in the treatment of equine PSCC.  相似文献   
55.
56.
MDM2和p53在大肠癌组织中的表达及其意义   总被引:1,自引:0,他引:1  
目的:探讨抑癌基因mdm2、p53在大肠癌组织中表达情况及与临床病理之间的关系。方法:采用免疫组化SABC法检测大肠癌79例,大肠腺瘤样息肉34例,正常大肠粘膜组织15例中MDM2、p53的表达。结果:MDM2在正常大肠组织、大肠腺瘤、大肠癌中表达阳性率分别为6.67%(1/15)、41.18%(14/34)、63.29%(50/79);p53阳性率分别为0、35.29%(12/34)、67.09%(53/79)。MDM2、p53在正常组织、大肠腺瘤、大肠癌组织中表达率逐渐增加(P〈0.01),两者与DukesC期、D期及远处转移相关,与年龄、性别及组织细胞分化程度无关。MDM2与p53表达之间呈正相关。结论:MDM2、p53高表达与大肠癌的发生、发展和预后相关。  相似文献   
57.
58.
利用噬菌体环七肽库筛选与肝癌细胞特异性结合的多肽,并对其亲和力进行生物学鉴定。以HL-7702为消减细胞,HepG2为筛选靶细胞,对噬菌体随机环七肽库进行4轮全细胞消减筛选,并随机挑取60个阳性噬菌体克隆,以ELISA法鉴定其与HepG2细胞的结合活性,并取阳性克隆进行测序分析,并合成多肽进行免疫细胞化学染色鉴定。经4轮筛选,噬菌体在靶细胞HepG2上出现明显富集;利用ELISA从随机挑选的60个噬菌体克隆中得到15个与肝癌细胞具有高结合力的阳性克隆,测序并进行序列分析比对发现氨基酸序列无同源性,经免疫细胞化学染色鉴定后,发现1条多肽序列亲和力较高,为提高抗菌肽对肿瘤细胞的靶向杀伤作用奠定基础。  相似文献   
59.
AIM:To investigate the relationship of microRNA-7 (miRNA-7) over-expression and epidermal growth factor receptor (EGFR)/phosphatidylinositol kinase-3 (PI3K)/protein kinase B (PKB, also called Akt) pathway in human nasopharyngeal carcinoma 5-8F cells. METHODS:The 5-8F cells were transfected with miRNA-7 mimics (carrying by Lipofectamine 2000). The expression of miRNA-7 was detected by real-time PCR. The cell proliferation was analyzed by CCK-8 assay. The cell colony-forming capability was determined by cell colony formation test. The expression of EGFR/PI3K/Akt at mRNA and protein levels was examined by real-time PCR and Western blotting. RESULTS:The expression level of miRNA-7 was significantly increased in 5-8F cells compared with negative control (NC) group and control group (P<0.01). The proliferation of NPC 5-8F cells was decreased extremely after tansfected with the miRNA-7 mimics (P<0.01), so did the result of the cell colony-formation test. The expression of EGFR/PI3K/Akt at mRNA and protein levels was significantly down-regulated compared with NC group and control group (P<0.01). CONCLUSION: Over-expression of miRNA-7 significantly inhibits the proliferation and colony-forming ability of nasopharyngeal carcinoma 5-8F cells by down-regulation of EGFR/PI3K/Akt pathway.  相似文献   
60.
目的:观察nm23表达与皮肤鳞状细胞癌(鳞癌)发生、发展与转移的关系。方法;采用免疫组织化学及图像分析技术检测66例皮肤鳞癌、12例淋巴结转移灶、21例假上皮瘤样增生及20例正常皮肤中nm23表达情况。结果:皮肤鳞癌中nm23表达下调,但鳞癌中nm23表达与鳞癌的转移、TNM分期、病理分化程度及发病部位无关。结论:nm23基因表达下调是发生在鳞癌演进过程中的一个早期事件。nm23可能不具有抑制皮肤鳞癌转移的功能。  相似文献   
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