溶瘤病毒治疗犬类癌症的研究进展

溶瘤病毒疗法是一种有前景的癌症治疗新策略。溶瘤病毒治疗主要依赖于非致病性病毒株的参与,在原发和转移肿瘤细胞中表现出选择性的病毒复制,造成细胞病理反应和特异性免疫反应,从而导致肿瘤细胞的裂解死亡,同时对正常细胞和组织却没有破坏作用或影响较小。已有大量研究对天然病毒和基因改造病毒(如腺病毒、犬瘟热病毒、呼肠病毒、牛痘病毒及重组病毒等)的溶瘤机制、给药途径、治疗效果及安全性等方面进行了广泛探讨。论文综述溶瘤病毒在治疗犬类癌症中常用的病毒种类,分析溶瘤病毒在肿瘤治疗中的研究现状,将有助于溶瘤病毒在犬类癌症治疗中的制剂开发。     

新城疫病毒在肿瘤治疗中的研究进展

新城疫病毒(NDV)是一种新兴的肿瘤生物治疗因子,反向遗传学操作技术的成熟使其在肿瘤治疗中的应用研究越来越深入。NDV能够通过其直接的溶瘤作用杀死肿瘤细胞,也可通过感染自体肿瘤细胞制成疫苗对患者进行主动特异性免疫治疗。但直接溶瘤效应会对患者产生一定的负面影响,自体肿瘤疫苗的免疫治疗也不能彻底杀死肿瘤细胞。目前,以NDV为复制型病毒载体的肿瘤基因治疗已成为该病毒肿瘤生物治疗的研究热点,这种基因治疗方法被认为是人类征服癌症的潜在手段。论文综述了NDV在肿瘤治疗中的研究与应用,对其溶瘤及抗肿瘤免疫学机制进行了分析,并对NDV作为载体的肿瘤基因治疗前景进行展望。     

猪A型塞内卡毒株CH-01-2015的溶瘤效果

为探究猪A型塞内卡毒株(SVA) CH-01-2015的溶瘤效果，本试验以SVA CH-01-2015为研究对象，在体外通过显微镜观察和细胞活性测定检测该毒株对前列腺癌细胞(PC-3)、非小细胞肺癌细胞(H1299、A549)、子宫内膜癌细胞(Ishikawa)、胶质瘤细胞(U251)和宫颈癌细胞(Hela)共6种肿瘤细胞的杀伤情况，通过病毒复制动力学测定检测SVA CH-01-2015在不同肿瘤细胞中的复制情况；在体内，通过PC-3裸鼠荷瘤试验检测SVA CH-01-2015的溶瘤效果，通过免疫组化和组织病理学染色检测肿瘤组织中病毒的复制以及治疗后肿瘤组织的形态变化。体外试验结果显示，与对照组细胞相比，感染SVA CH-01-2015的PC-3、H1299和Ishikawa肿瘤细胞被显著裂解，而U251、A549和Hela肿瘤细胞形态无显著变化；且与对照组细胞相比，SVA CH-01-2015毒株能极显著杀伤PC-3、H1299和Ishikawa肿瘤细胞(P<0.01),对U251、A549和Hela肿瘤细胞几乎无杀伤作用(P>0.05);以感染复数(MOI)为1的SVA...     

犬乳腺肿瘤的临床分析

犬乳腺肿瘤是临床多发的犬肿瘤性疾病,约占犬临床肿瘤性疾病的50%。成年及老年母犬较易发生,临床常见良性瘤包括腺瘤和纤维素瘤,恶性肿瘤包括原发性乳腺癌和肉瘤。论文结合国内外相关资料,主要从该病的诊断方法、治疗等方面进行综述和分析,为犬乳腺肿瘤的诊断与治疗提供参考     

犬黑色素瘤治疗研究进展

犬黑色素瘤是一种恶变率和转移率高的肿瘤,且多发生于口腔,由于疾病发展迅速,如果不尽早治疗,在疾病发展后期,患犬的生存期和生存质量会显著下降。另一方面,现有临床传统肿瘤治疗方法,如手术、化疗及放疗,对于犬黑色素瘤的治疗效果不尽如人意,且在实际应用中受限。论文通过结合人医和兽医黑色素瘤的研究进展,对目前关于犬黑色素瘤的免疫疗法、靶向治疗、细胞因子和溶瘤病毒等新型治疗方法进行总结及分析,期望能够对我国小动物临床应用和科研工作有所启发。     

犬口腔乳头状瘤的诊疗病例

正犬口腔乳头状瘤是一种接触性良性肿瘤病,由犬乳头状瘤病毒引起。该病毒的表现型有两种,一种是感染1岁以下的幼犬引起口腔肿瘤,另一种是感染老年犬引起皮肤肿瘤。犬口腔乳头状瘤在临床中不多见,大量或较大的口腔肿瘤会引起吞咽困难、口臭、流涎、口腔炎症等。因此该病需要尽早进行手术治疗。     

紫杉醇和姜黄素联合使用的体内外抗乳腺肿瘤效果

为了探究紫杉醇(TAX)、姜黄素(CUR)联合使用在体内、体外抗乳腺肿瘤的作用,本试验采用CCK-8法测定TAX、CUR单体及二者联合使用对犬乳腺肿瘤细胞系7364的细胞增殖抑制率;将荷瘤小鼠随机分为生理盐水组、TAX组、TAX+CUR组,考察TAX、CUR联合使用对小鼠乳腺肿瘤细胞系(4T1)皮下移植瘤模型的抑瘤药效。体外试验结果显示,TAX单体药物对犬乳腺肿瘤细胞系7364的半数抑制浓度(IC₅₀)为0.191μmol/L,CUR单体药物IC₅₀为53.160μmol/L,CUR(0.25～2μmol/L)和TAX(0.013～0.4μmol/L)联合给药时TAX IC₅₀与其单独给药相比显著降低,表明TAX和CUR在一定比例、浓度时具有协同抗肿瘤效应。动物试验结果显示,TAX+CUR组初次给药后第11天肿瘤体积显著低于生理盐水组(P<0.05);治疗结束后完整剥离肿瘤,测得TAX+CUR组的抑瘤率为17.3%,而TAX组无明显抑瘤效果。结果表明TAX和CUR在一定配比、浓度条件下对犬乳腺肿瘤细胞系7364具有...     

一例泰迪犬肿瘤疾病的诊断与治疗

为了解当前犬肿瘤疾病的临床诊断及治疗现状，本文记录了一例患病泰迪犬的临床症状、治疗过程及预后情况，并对患病犬进行临床综合诊断、实验室诊断、影像学检查和手术摘除疗法。通过对切除肿瘤进行病理组织学观察，进一步研判了肿瘤类型。经综合诊断，该泰迪犬患肥大细胞瘤（恶性肿瘤），已向乳腺周围和口腔局部扩散，目前正在使用长春新碱化疗药物维持，需定期复诊。     

犬细小病毒诊治报告

犬细小病毒病是由犬细小病毒(CPV)引起的一种急性,热性接触性传染病,临床上的出血性肠类和非化脓性心肌类为主要特征,笔者200~2005年门诊救治的30多例本病病例,采取对症疗法和使用单克隆抗体,如犬五联高免血清等特异性治疗,收到了较为显著的治疗效果,治愈率达到85%以上。现将治     

家禽抗肿瘤和抗病毒感染新制剂——干扰素

家禽肿瘤和病毒感染性疾病的有效治疗一直是困惑禽病防制的难题之一。至今仍未有一类药物能特异性地有效杀灭家禽病毒性病原，干扰和抑制其病原的复制。细胞因子干扰素(Interferon,IFN)的出现及其临床试验证明，该类细胞因子在病毒性禽病和家畜肿瘤的治疗上极具临床应用前景。1957年Isaacs和Lindenmann首先发现了病毒干扰现象，即病毒感染的细胞能产生一种因子，作用于其他细胞干扰病毒的复制，因而命名为干扰素。目前已知干扰素并不能直接杀伤病毒，而是诱导宿主细胞产生数种酶，干扰病毒的基因转录或病毒蛋白组分的翻译。根据产生干扰…     

Anti‐tumour activity of oncolytic Western Reserve vaccinia viruses in canine tumour cell lines,xenografts, and fresh tumour biopsies

Cancer is one of the most common reasons for death in dogs. One promising approach is oncolytic virotherapy. We assessed the oncolytic effect of genetically modified vaccinia viruses in canine cancer cells, in freshly excised tumour biopsies, and in mice harbouring canine tumour xenografts. Tumour transduction efficacy was assessed using virus expressing luciferase or fluorescent marker genes and oncolysis was quantified by a colorimetric cell viability assay. Oncolytic efficacy in vivo was evaluated in a nude mouse xenograft model. Vaccinia virus was shown to infect most tested canine cancer cell lines and primary surgical tumour tissues. Virus infection significantly reduced tumour growth in the xenograft model. Oncolytic vaccinia virus has antitumour effects against canine cancer cells and experimental tumours and is able to replicate in freshly excised patient tumour tissue. Our results suggest that oncolytic vaccinia virus may offer an effective treatment option for otherwise incurable canine tumours.     

The oncolytic effects of reovirus in canine solid tumor cell lines

Oncolytic virotherapy is a new strategy for cancer treatment for humans and dogs. Reovirus has been proven to be a potent oncolytic virus in human medicine. Our laboratory has previously reported that canine mast cell tumor and canine lymphoma were susceptible to reovirus. In this study, canine solid tumor cell lines (mammary gland tumor, osteosarcoma and malignant melanoma) were tested to determine their susceptibility towards reovirus. We demonstrated that reovirus induces more than 50% cell death in three canine mammary gland tumors and one canine malignant melanoma cell line. The reovirus-induced cell death occurred via the activation of caspase 3. Ras activation has been shown to be one of the important mechanisms of reovirus-susceptibility in human cancers. However, Ras activation was not related to the reovirus-susceptibility in canine solid tumor cell lines, which was similar to reports in canine mast cell tumor and canine lymphoma. The results of this study highly suggest that canine mammary gland tumor and canine malignant melanoma are also potential candidates for reovirus therapy in veterinary oncology.     

Oncolysis of canine tumor cells by myxoma virus lacking the serp2 gene

Objective-To determine the oncolytic efficacy of an attenuated form of myxoma virus lacking the serp2 gene in canine tumor cells. Sample-Primary cells were isolated from tumors that were surgically removed from dogs and from connective tissue obtained from the cadaver of a dog. Cells of various established cell lines from tumors and nontumorous tissues were obtained. Procedures-Experiments were performed with cells in monolayer culture. Cell cultures were inoculated with wild-type myxoma viruses or myxoma viruses lacking the serp2 gene, and measures of cytopathic effects, viral growth kinetics, and cell death and apoptosis were determined. Results-Myxoma viruses replicated in cells of many of the primary and established canine tumor cell lines. Canine tumor cells in which expression of activated protein kinase B was upregulated were more permissive to myxoma virus infection than were cells in which expression of activated protein kinase B was not upregulated. Myxoma viruses lacking the serp2 gene caused more cytopathic effects in canine tumor cells because of apoptosis than did wild-type myxoma viruses. Conclusions and Clinical Relevance-Results of the present study indicated myxoma viruses lacking the serp2 gene may be useful for treatment of cancer in dogs. Impact for Human Medicine-Results of the present study may be useful for development of novel oncolytic treatments for tumors in humans.     

Oncolytic potential of rodent parvoviruses for cancer therapy in humans: a brief review

Summary Rodent parvoviruses are promising candidates for oncolytic virotherapy of cancer in humans because of their oncotropism (preferential killing of transformed cells) in the absence of pathogenicity. Here, we give an overview concerning the possible application of parvovirus H-1 for cancer therapy, with specific emphasis on malignant brain tumours in humans.     

Oncolytic gene therapy for canine cancers: teaching old dog viruses new tricks

The use of viruses to treat cancer has been studied for decades. With the advancement of molecular biology, viruses have been modified and genetically engineered to optimize their ability to target cancer cells. Canine viruses, such as distemper virus and adenovirus, are being exploited for the treatment of canine cancer as the dog has proven to be a good comparative model for human cancer research and proof of concept investigations. In this review, we introduce the concept of oncolytic viruses and describe some of the preliminary attempts to use oncolytic viruses for the treatment of canine cancer.     

Tumour necrosis factor‐alpha‐induced protein 8 (TNFAIP8) expression associated with cell survival and death in cancer cell lines infected with canine distemper virus

Oncolytic virotherapy is a novel strategy for treatment of cancer in humans and companion animals as well. Canine distemper virus (CDV), a paramyxovirus, has proven to be oncolytic through induction of apoptosis in canine‐derived tumour cells, yet the mechanism behind this inhibitory action is poorly understood. In this study, three human mammary tumour cell lines and one canine‐derived adenofibrosarcoma cell line were tested regarding to their susceptibility to CDV infection, cell proliferation, apoptosis, mitochondrial membrane potential and expression of tumour necrosis factor‐alpha‐induced protein 8 (TNFAIP8). CDV replication‐induced cytopathic effect, decrease of cell proliferation rates, and >45% of infected cells were considered death and/or under late apoptosis/necrosis. TNFAIP8 and CDVM gene expression were positively correlated in all cell lines. In addition, mitochondrial membrane depolarization was associated with increase in virus titres (p < 0.005). Thus, these results strongly suggest that both human and canine mammary tumour cells are potential candidates for studies concerning CDV‐induced cancer therapy.     

Effect of the VP3 gene of chicken anemia virus on canine mammary tumor cells

OBJECTIVE: To investigate the antitumor effect of the chicken anemia virus (CAV) VP3 gene in canine mammary tumor (CMT) cells. SAMPLE POPULATIONS: Established primary canine cell lines that originated from epithelial cells of resected CMTs and nonneoplastic mammary gland epithelial (MGE) cells. PROCEDURES: Expression vectors and lentiviral vectors encoding the VP3 gene from a Taiwan-Ilan isolate of CAV were used to deliver the VP3 gene into CMT cells and nonneoplastic MGE cells. Ectopic gene expression and the pro-apoptotic effect of the VP3 gene on CMT and nonneoplastic MGE cells by either transfection or viral infection were evaluated via immunofluorescence microscopy, western blot analysis, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling analysis. RESULTS: Overexpression of the enhanced green fluorescent protein-VP3 fusion protein was detected predominantly in the nuclei of CMT cells. In contrast, the VP3 protein was localized to the cytoplasm of nonneoplastic MGE cells. Among the fusion protein-expressing CMT cells, most underwent characteristic changes of apoptosis, whereas apoptosis was not detected in fusion protein-expressing, nonneoplastic MGE cells. Induction of apoptosis by VP3 gene overexpression in CMT cells was associated with the caspase-9-, but not the caspase-8-, mediated apoptosis pathway. CONCLUSIONS AND CLINICAL RELEVANCE: These data indicate that the VP3 gene of the CAV induces apoptosis in malignant CMT cells, but not in nonneoplastic canine MGE cells. On the basis of such tumor cell-specific killing, the VP3 gene may be a promising agent for the treatment of malignant mammary gland tumors in dogs.     

The potential of the combined use of targeted type I interferon pathway inhibitors and oncolytic viruses to treat sarcomas

Replicating oncolytic viruses (OVs) are appealing, new, FDA‐approved, therapeutic options for humans with head and neck cancers and melanomas. These treatments are not yet available for veterinary patients, but recent clinical trials have shown several OVs to be safe in dogs and cats. Specific viruses being used to treat sarcomas in dogs include modified canine adenovirus 2, myxoma virus, vesicular stomatitis virus and reovirus. In cats with vaccine‐associated sarcomas, poxviruses have been injected postoperatively and a reduced rate of tumour recurrence was documented. To date, the response rates of canine and feline patients to OV therapy have been variable (as they are in people). Optimal methods of OV administration and dosing schedules continue to be evaluated. One way to improve outcomes of OV therapy in veterinary patients may be to use OVs in combination with other immunomodulatory therapies. This review discusses the potential utility of concurrent therapy with an OV and an inhibitor of the type I interferon pathway.     

Oncolytic reovirus synergizes with chemotherapeutic agents to promote cell death in canine mammary gland tumor

The oncolytic effects of reovirus in various cancers have been proven in many clinical trials in human medicine. Oncolytic virotherapy using reovirus for canine cancers is being developed in our laboratory. The objective of this study was to examine the synergistic anti-cancer effects of a combination of reovirus and low doses of various chemotherapeutic agents on mammary gland tumors (MGTs) in dogs. The first part of this study demonstrated the efficacy of reovirus in canine MGTs in vitro and in vivo. Reovirus alone exerted significant cell death by means of caspase-dependent apoptosis in canine MGT cell lines. A single injection of reovirus impeded growth of canine MGT tumors in xenografted mice, but was insufficient to induce complete tumor regression. The second part of this study highlighted the anti-tumor effects of reovirus in combination with low doses of paclitaxel, carboplatin, gemcitabine, or toceranib. Enhanced synergistic activity was observed in the MGT cell line treated concomitantly with reovirus and in all the chemotherapeutic agents except toceranib. In addition, combining reovirus with paclitaxel or gemcitabine at half dosage of half maximal inhibitory concentration (IC₅₀) enhanced cytotoxicity by activating caspase 3. Our data suggest that the combination of reovirus and low dose chemotherapeutic agents provides an attractive option in canine cancer therapy.     

2例犬肝胆管细胞癌的病理学诊断

肝胆管细胞癌是来源于肝胆管上皮细胞的恶性肿瘤,在多物种中都有发生。笔者运用组织病理学和免疫组织化学的方法,对2例犬肝肿瘤进行了诊断。结果显示：肝肿瘤眼观均为圆球形白色肿块,组织病理学检查肿瘤组织由呈腺管状排列的瘤细胞构成,有的腺管中央有坏死脱落的细胞,有的有黏液样物质,腺管间以薄的纤维结缔组织分隔,瘤组织有大片的坏死。瘤细胞多呈卵圆形,细胞核大、卵圆形,核分裂象多见,瘤细胞的CK19阳性表达,而CK18和AFP呈阴性表达。根据组织病理学和免疫组织化学检查结果判断,2例犬肝肿瘤为肝胆管细胞癌,本研究为犬肝肿瘤诊断积累了病理学资料。