Effect of Agaricus blazei Murrill extract on HT-29 human colon cancer cells in SCID mice in vivo

Agaricus blazei Murrill (ABM) popularly known as 'Cogumelo do Sol' in Brazil, or 'Himematsutake' in Japan, is a mushroom native to Brazil and widely cultivated in Japan for its medicinal uses and is now considered one of the most important edible and culinary-medicinal biotechnological species. This study is the first tumor growth model to evaluate the amelioratory effect of ABM extract using HT-29 human colon cancer cells in severe combined immunodeficiency (SCID) mice. Forty SCID mice were inoculated with HT-29 cells to induce tumor formation and were then divided into four groups. All the four groups (control, low, medium and high concentration treatment) of mice were separately orally administered 0 mg, 1.125 mg, 4.5 mg or 45 mg ABM extract daily. After six weeks of treatment, 8 out of the 40 mice had not survived including one mouse which scored +++ (tumor up to 15 mm diameter) and four mice which scored ++++ (tumor over 15 mm diameter) in the control group and three mice which scored ++++ on the low-dose ABM treatment. After high- or medium-dose treatment, all ten mice in each group survived. The oral administration of ABM does not prevent tumor growth, as shown by increased tumor mass, but compared with the control group, the tumor mass seems to grow more slowly depending on the ABM dose.     

A novel plasmin-inhibitor inhibits the growth of human tumor xenografts and decreases metastasis number

The novel plasmin inhibitor YO-2, which also exerts an apoptosis-inducing effect on various human tumor cell cultures, was examined regarding its tumor growth inhibitory and antimetastatic action. The tumor growth inhibitory effect of YO-2 was studied using HT-29 human colon carcinoma, HT-18 human melanoma and HT-58 human B cell lymphoma inoculated as xenografts into immuno-deprived mice. Antimetastatic activity was tested on the B16 mouse melanoma muscle-lung model. YO-2 inhibited the growth of all xenografts in the range of 40-50%, when administered s.c. at a dose of 2.0 mg/kg (HT-29, HT-58) or orally at a dose of 0.4 mg/kg (HT-18). YO-2 decreased the number of lung metastasis found in mice inoculated i.m. with B16 melanoma, 4 mg/kg being the most effective. Since YO-2 is the only plasmin inhibitor having antihemorrhagic and also antitumor effect, this compound could be rationally used in combination therapy of neoplastic disease, especially when hemorrhage aggravates the course of the disease.     

螺旋藻多糖硫酸酯化修饰前后抗肿瘤及免疫活性的研究

比较螺旋藻多糖硫酸酯化修饰前后体内外抗肿瘤及免疫活性.采用MTT比色法研究药物在体外对人肿瘤细胞株的抑制作用,促进正常小鼠脾淋巴细胞的增殖活性以及对荷瘤小鼠NK和CTL细胞活性的影响.采用移植性肿瘤实验方法考察了药物对小鼠S180肉瘤的抑制作用.结果显示,螺旋藻多糖（NPSP）对肿瘤细胞株几乎无细胞毒作用,硫酸酯化螺旋藻多糖（SNPSP）对肿瘤细胞株具有显著的细胞毒作用,其中对SMMC-7721人肝癌细胞株抑制率最高达50%.NPSP50 mg/kg对小鼠S180肉瘤无抑制,相同剂量的SNPSP对小鼠S180肉瘤的抑制率达35.42%.NPSP具有促进脾淋巴细胞增殖作用,但对ConA和LPS诱导的脾淋巴细胞增殖反应无促进作用,SNPSP促进脾淋巴细胞增殖作用较NPSP增强,同时对ConA和LPS诱导的脾淋巴细胞增殖反应也具有明显的促进作用.NPSP和SNPSP均能促进荷瘤小鼠NK细胞和CTL细胞活性,其中SNPSP促进CTL细胞活性较NPSP增强.     

化合物209对人结直肠癌细胞HT-29的体内和体外作用(英文)

化合物209是一个新合成的氨基二硫代甲酸酯类化合物,它在体外水平可以抑制肿瘤细胞的增殖,但是化合物209的体内抗肿瘤作用及其抗肿瘤机制并不明确。本文探究了化合物209对人结直肠癌细胞HT-29的作用并初步探讨了相关机制。体外研究表明,化合物209可以显著抑制HT-29细胞的增殖;体内研究结果表明,化合物209可以显著抑制裸鼠HT-29移植瘤的生长,但是对裸鼠体重和白细胞无影响。流式细胞分析实验结果表明,化合物209可将HT-29细胞阻滞于细胞周期的G1期。同时,化合物209能上调体外培养HT-29细胞中p27,cyclin E,CDK2,cyclin D1和CDK4的表达。在体内瘤组织中上述蛋白表达情况与体外实验结果一致。这些结果说明,化合物209具有较好的抗肿瘤活性,其抗肿瘤作用与细胞周期阻滞及其相关蛋白的表达变化有关。     

Moxifloxacin increases anti-tumor and anti-angiogenic activity of irinotecan in human xenograft tumors

Camptothecins (CPTs) are topoisomerase I inhibitors chemotherapeutic agents used in combination chemotherapy. We showed previously that combination of moxifloxacin (MXF) and CPT induced inhibitory effects on topoisomerase I activity, on proliferation of HT-29 cells in vitro and enhanced apoptosis, compared to CPT alone. Analysis of secretion of the pro-angiogenic factors IL-8 and VEGF showed significant reduction by MXF. Using a murine model of human colon carcinoma xenograft, we compared the effects of MXF/CPT in vitro to MXF/irinotecan combination in vivo. We show that the MXF/CPT inhibitory effects observed in vitro are reflected in the inhibition of the progressive growth of HT-29 cells implanted in SCID mice. Using caliper measurements, Doppler ultrasonography, image analyses and immunohistochemistry of nuclear proteins (Ki-67) and vascular endothelial cells (CD-31) we show that addition of MXF (45 mg/kg) to a relatively ineffective dose of irinotecan (20 mg/kg), results in a 50% and 30% decrease, respectively, in tumor size and a decrease in Ki-67 staining. Power Doppler Ultrasound showed a significant, pronounced decrease in the number of blood vessels, as did CD-31 staining, indicating decreased blood flow in tumors in mice treated with MXF alone or MXF/irinotecan compared to irinotecan. These results suggest that the combination of MXF/irinotecan may result in enhanced anti-neoplastic/anti-angiogenic activity.     

The role of NK cells in antitumor activity of dietary fucoidan from Undaria pinnatifida sporophylls (Mekabu)

Fucoidan from Mekabu (sporophyll of Undaria pinnatifida), a dietary alga, exerts antitumor activity possibly through enhancing the immune response. The present report describes the effects of dietary Mekabu fucoidan on the tumor growth of mouse A20 leukemia cells and on T cell-mediated immune responses in T cell receptor transgenic (DO-11 - 10 - Tg) mice. The animals were fed with a diet containing 1% Mekabu fucoidan (0.034 +/- 0.003 g/mouse/day) for 10 days and subcutaneously (s. c.) inoculated with A20 leukemia cells. Thereafter, the mice were fed with the diet containing fucoidan for 40 days. Mekabu fucoidan inhibited tumors by 65.4 %. We studied how the killer activities of T cell-mediated and natural killer (NK) cells are augmented in DO-11 - 10 mice fed with Mekabu fucoidan. The cytolytic activities of ovalbumin (OVA), which is specific against OVA-transfected A20 (OVA-A20) B lymphoma cells, and NK cells against YAC-1 were significantly enhanced in the mice fed with fucoidan compared with a basic diet. Thus, these findings suggested that Mekabu fucoidan mediates tumor destruction through Th1 cell and NK cell responses.     

CCI-779 plus cisplatin is highly effective against human melanoma in a SCID mouse xenotranplantation model

BACKGROUND: This study set out to investigate the antitumor effects of a treatment strategy combining the mTOR inhibitor CCI-779 with cisplatin in vitro and in a human melanoma SCID mouse model. METHODS: In vitro 518A2, Mel-JUSO or 607B cell lines were incubated with CCI-779, cisplatin and CCI-779 plus cisplatin. Based on these results, a 4-group, parallel, controlled experimental study design was initiated in vivo. SCID mice were injected with melanoma cells, and after the development of tumors the mice received daily injections of CCI-779 or solvent. On treatment days 2 and 6 cisplatin or mock solution were administered. RESULTS: In vitro a synergistic antitumor effect was observed for the treatment regimen of CCI-779 plus cisplatin. In SCID mice after 2 weeks of therapy with CCI-779 plus cisplatin 4 of 6 tumors of the 518A2 cell line were completely eradicated. In the two remaining 518A2 xenografts this treatment strategy reduced the tumor weight by 94 +/- 9% compared to solvent. CCI-779 plus cisplatin also exerted a significant antitumor effect in Mel-JUSO and 607B xenografts compared to mock-treated animals. CONCLUSION: We provide circumstantial evidence that the use of CCI-779 plus cisplatin might qualify as a promising strategy in the treatment of human melanoma.     

In vivo therapeutic effects of IFN-gamma on human myelogenous leukemia in a severe combined immunodeficiency mouse model

BACKGROUND: Results of clinical trials of IFN-gamma on the treatment of various types of leukemia are not so promising, regardless of the antiproliferative activity against leukemic cells and expected immunomodulatory effects. In this study, we have re-evaluated the anti-leukemic effects of natural human IFN-gamma (nHuIFN-gamma) using an established human myelogenous leukemia model in SCID mice. MATERIALS AND METHODS: SCID mice transplanted with human myelogenous leukemia cell line ML-2S received subcutaneously 5 x 10(4) IU/mouse of nHuIFN-gamma at 5 times/week for 5 weeks. RESULT: nHuIFN-gamma significantly prolonged the lifespan of SCID mice in leukemic crisis. Percentages of ML-2S cells in the peripheral blood were also significantly decreased by the IFN-gamma treatment. Histopathological examination revealed that IFN-gamma treatment suppressed the replacement of pancreatic cells by tumor cells and the formation of tumor masses in the intestine. CONCLUSIONS: These results suggest that IFN-gamma is effective against human myeloid leukemia, especially extramedullary tumor mass-forming type in the peritoneal organs. Our results further suggest that studies employing SCID mice leukemia model would help in devising appropriate therapeutic strategies of IFN-gamma based on the specific characteristics of each leukemia subtype.     

p-JNK在结肠癌组织中的表达及抑制JNK通路后HT-29细胞增殖和凋亡变化

目的研究p-JNK在结肠癌组织中的表达以及抑制JNK信号通路后人结肠癌HT-29细胞增殖和凋亡的变化。方法使用免疫组织化学方法检测50例结肠癌组织标本和50例正常结肠组织标本中p-JNK的表达情况并和临床资料进行比较分析;在人结肠癌细胞株HT-29中使用SP600125抑制JNK信号通路后,MTT法检测细胞增殖,TUNEL法检测凋亡。结果 p-JNK在结肠癌组织中的表达水平明显高于正常对照组织(P<0.05);并和淋巴结转移、肿瘤分化程度、肿瘤的侵犯深度相关(P<0.05);而与肿瘤部位无关。抑制JNK信号通路后,HT-29细胞中的p-JNK表达降低(P<0.05);增殖减少,凋亡增加(P<0.05)。结论在结肠癌组织中存在p-JNK的高表达,抑制JNK信号通路能降低人结肠癌细胞株HT-29细胞的增殖,并促进凋亡;JNK信号通路和结肠癌的发生发展有关。     

Bryostatin 1 induces differentiation and potentiates the antitumor effect of Auristatin PE in a human pancreatic tumor (PANC-1) xenograft model

Pancreatic cancer has the worst prognosis of all cancers with a dismal 5-year survival rate. Hence, there is a tremendous need for development of new and effective therapy for this tumor. In an earlier study we reported a potent antitumor activity of Auristatin PE (AuriPE) against pancreatic tumor. In addition, we have also reported that bryostatin 1 (bryo1) induces differentiation of leukemia cells, but the effect of bryo1 has not been investigated in pancreatic tumors. This is the first report where we demonstrate that bryo1 induces differentiation and potentiates the antitumor effect of AuriPE in a human pancreatic tumor (PANC-1) xenograft model. A xenograft model was established by injecting the PANC-1 cells s.c. in severe combined immune deficient (SCID) mice. After development of the s.c. tumors, tumors were dissected and small fragments were transplanted in vivo to new SCID mice, with a success rate of 100% and a doubling time of 4.8 days. The SCID mouse xenograft model was used to test the in vivo differentiation effect of bryo1 and its efficacy when given alone or in combination with AuriPE. Sections from paraffin-embedded tumors excised from untreated (control) SCID mice revealed typical poorly differentiated adenocarcinoma of the pancreas. Interestingly, sections of s.c. tumors taken from bryo1-treated mice revealed carcinomas that were much lower grade and less aggressive, and displayed prominent squamous and glandular differentiation. In this study, the tumor growth inhibition (T/C), activity score and cure rate for bryo1, AuriPE and bryo1+AuriPE were 80%, (+) and 0/4; 0.0%, (++++) and 3/5; and 0.0%, (++++) and 3/4, respectively. Mice treated with either AuriPE or bryo1+AuriPE were free of tumors for more than 150 days and were considered cured. The use of bryo1 as a novel differentiating agent and its combination with AuriPE should be further explored for the treatment of adenocarcinoma of the pancreas.     

Enhanced therapeutic efficacy of a novel liposome-based formulation of SN-38 against human tumor models in SCID mice

SN-38 is an active metabolite of CPT-11. The poor solubility of SN-38 in any pharmaceutically acceptable solvent and pH-dependent activity has limited its clinical use. Our objective was to evaluate an easy-to-use liposome-based formulation of SN-38 (LE-SN38) and compare the antitumor activity with its pro-drug CPT-11 against cancer cell lines and human xenograft tumor models. The cytotoxicity of LE-SN38 and CPT-11 was determined in four human cancer cell lines using the sulforhodamine B assay. The therapeutic efficacy was tested against human colon (HT-29) and breast (MX-1) xenograft tumor models in SCID mice. LE-SN38 with greater than 95% drug entrapment was found to be highly cytotoxic against four different cell lines with GI50 values of less than 0.1 microM. In the HT-29 tumor model, LE-SN38 (q x d5) at 2, 4 or 8 mg/kg resulted in 33, 81 and 91% tumor growth inhibition, respectively, compared to the drug-free liposome group. In contrast, similar dose levels of CPT-11 treatment led to only 2, 36 and 46% growth inhibition. For the MX-1 model, LE-SN38 (q x d5) regressed tumor growth by 44 and 88% at 4 and 8 mg/kg dose, respectively, whereas no regression was observed in the CPT-11-treated group. We conclude that LE-SN38 is a novel liposome-based formulation with enhanced therapeutic efficacy against human tumor models.     

Calcium pterin as an antitumor agent

A series of in vivo studies are reported that provide evidence for an immunologically mediated mechanism for the antitumor response from a calcium pterin (CaPterin) suspension. Strong antitumor efficacy was demonstrated in fully immunocompetent female C3H/HeN-MTV+ mice (retired breeders) presenting spontaneous mammary gland adenocarcinomas. Comparison of results obtained by testing CaPterin in either nude or SCID mice (severely compromised immunodeficient) implanted with MDA-MB-231 human cancer cells showed a significant antitumor response in the nudes and no response in the SCIDs. This comparison argues for B-cell immunological involvement in the mechanism of CaPterin antitumor activity since nude mice possess B-cell capability while SCID mice do not. This comparison also indicates that there is no measurable direct cancer cell toxicity from the CaPterin. Results showing no CaPterin antitumor efficacy against EMT6 tumor cells implanted in Balb/c mice also suggest an antitumor mechanism involving B-cells, since transforming growth factor beta (TGF-beta), produced by EMT6 cells, is known to cause B-cell apoptosis. Taken together, these results, along with those of other researchers, indicate that CaPterin's antitumor mechanism involves antibody-dependent cellular cytotoxicity (ADCC) mediated, for example, by natural killer (NK) cells, interlukin-2, and CaPterin.     

力达霉素对钾离子通道HERG高表达肿瘤细胞的增殖抑制及其与化疗药物的协同作用

探讨力达霉素(LDM)对钾离子通道HERG高表达肿瘤细胞的增殖抑制及其与化疗药物的协同作用。用MTT法观察LDM和多种抗癌药的联合应用对人A549和HT-29细胞以及转染HERG钾通道A549细胞的抑制作用;用人结肠癌HT-29裸鼠模型,观察LDM和HCPT联合的抑瘤作用,用药物相互作用指数评价药物联合作用。LDM显著抑制A549细胞和HT-29细胞的增殖,其IC50值分别为2.14和4.64 ng.mL-1,其对HERG钾通道高表达的HT-29细胞的增殖抑制作用弱于对HERG钾通道低表达A549细胞的作用;从IC50值来看,LDM也能抑制HERG钾通道稳定转染的A549细胞的增殖,但这种抑制作用明显弱于稳定转染了空白质粒的A549细胞;LDM分别与氟尿嘧啶(5-FU)、多柔比星(DOX)、羟喜树碱(HCPT)联用,能协同抑制HERG钾通道高表达的HT-29细胞的增殖。LDM与5-FU联用,CDI值均大于0.75;LDM与DOX联用,CDI值均大于0.70;LDM与HCPT联用,CDI值小于0.70;其中,与HCPT联用的协同作用效果最强。5-FU对肿瘤细胞的生长抑制作用不受HERG钾通道的调节,DOX的化疗...     

Virulizin, a novel immunotherapy agent, stimulates TNFalpha expression in monocytes/macrophages in vitro and in vivo

Virulizin, a novel biological response modifier, has demonstrated broad antitumor efficacy in a variety of human tumor xenograft models including melanoma, pancreatic cancer, breast cancer, ovarian cancer and prostate cancer. Previous studies have demonstrated a significant role of macrophages and NK cells in the antitumor mechanism of Virulizin. Increased activity and expansion of macrophages and NK cells has been observed in mice treated with Virulizin. In the present study, the effects of Virulizin on TNFalpha expression were investigated in vitro and in vivo. CD-1 nude mice were treated with Virulizin daily for 5 days. Quantitative RT-PCR demonstrated that the level of TNFalpha mRNA increased in peritoneal macrophages isolated from Virulizin-treated mice as compared to the control group. An increase in TNFalpha protein expression was also observed, as assessed by flow cytometric analysis. Increased levels of TNFalpha mRNA were seen in human tumor xenografts following treatment of tumor-bearing mice with Virulizin. In the presence of LPS, Virulizin also stimulated TNFalpha protein secretion and mRNA expression in human monocytic U937 cells and mouse macrophage RAW264.7 cells in vitro in a time- and dose-dependent manner. U937 cells treated with Virulizin showed a significantly enhanced cytotoxicity that was eliminated upon neutralization of TNFalpha. Virulizin also induced the phosphorylation of IkappaB, suggesting that induction of TNFalpha expression by Virulizin is mediated by activation of NFkappaB. The results indicate that Virulizin-induced TNFalpha expression contributes to modulation of immune responses and antitumor activities.     

异叶败酱总苷片对人大肠癌HT-29细胞凋亡的影响

目的：研究异叶败酱总苷片对人大肠癌细胞凋亡的影响及作用机制。方法：建立人大肠癌HT-29裸鼠移植瘤模型，设立异叶败酱总苷片低、中、高剂量组和空白组、5-氟脲嘧啶（5-FU）＋甲酰四氢叶酸钙（CF）对照组，给药8周后处死裸鼠，瘤体称重,末端原位标记染色法（TUEL）检测凋亡指数，分别行半胱天冬氨酸蛋白酶-3（caspase-3），Bax和Bcl-2免疫组化染色，图象分析系统定量检测并比较该3种物质表达情况。结果：异叶败酱总苷片各组瘤重小于空白对照组，而凋亡指数均高于空白对照组和5-FU＋CF组，其中高剂量组与空白对照组和5-FU＋CF组比较差异有极显著性（P＜0．01）。异叶败酱总苷片各组移植瘤caspase-3表达及Bax、Bcl-2表达的相对比率（Bax／Bcl-2）均高于空白对照组。结论：异叶败酱总苷片具有诱导人大肠癌HT-29裸鼠移植瘤细胞凋亡的作用，其机制可能与促进移植瘤caspase-3表达及增大Bax／Bcl-2表达比率有关。     

The anti-lung cancer activity of SEP is mediated by the activation and cytotoxicity of NK cells via TLR2/4 in vivo

Strongylocentrotus nudus egg polysaccharide (SEP) has been reported to display antitumor activity. However, the effects of SEP and its underlying mechanism in the treatment of lung cancer remain unclear, particularly with an immunodeficient mouse model of human non-small cell lung cancer (NSCLC). In the present study, we investigated the anti-lung cancer effects of SEP and its underlying mechanism of action in both Lewis lung cancer (LLC)-bearing C57/BL6J mice and human NSCLC H460-bearing nude mice. Although SEP showed no inhibitory effects on tumor cells in vitro, it markedly stimulated the percentage of CD3−NK1.1⁺ cells and natural killer (NK) cell cytotoxicity in the spleens of nude mice and C57/BL6J mice. In LLC-bearing mice, SEP not only inhibited tumor growth but also promoted NK-mediated cytotoxicity, the NK1.1⁺ cell population, and IL-2 and IFN-γ secretion. SEP significantly suppressed H460 growth in nude mice, which was abrogated by the selective depletion of NK cells via the intraperitoneal injection of anti-asialo GM-1 antibodies. Furthermore, anti-TLR2/4 antibodies blocked both SEP and NK cell binding and SEP-induced perforin secretion. SEP-induced proliferation and IFN-γ secretion by NK cells in wild type mice were partially impaired in TLR2 or TLR4 knockout mice. These results suggest that SEP-promoted NK cytotoxicity, which was partially mediated via TLR2 and TLR4, was the main contributing factor to lung cancer inhibition in vivo and that SEP may be a potential immunotherapy candidate for the treatment of lung cancer.     

In vivo investigation of tolerance and antitumor activity of cisplatin-loaded PLGA-mPEG nanoparticles

The tolerance of BALB/c mice to different doses of blank and cisplatin-loaded PLGA-mPEG nanoparticles and the in vivo anticancer activity of these nanoparticles on SCID mice xenografted with colorectal adenocarcinoma HT 29 cells were investigated. Nanoparticles with an average size of 150-160 nm and approximately 2% w/w cisplatin content were prepared by a modified emulsification and solvent evaporation method. Normal BALB/c mice tolerated three weekly intravenous injections of a relatively high dose of blank PLGA-mPEG nanoparticles (500 mg/kg, equivalent to about 10 mg nanoparticles/mouse) and three weekly intravenous injections of a high dose of nanoparticle-entrapped cisplatin (10 mg/kg). Also, histopathology examination indicated that there were no differences in the kidneys or spleens from animals treated with cisplatin-loaded nanoparticles or blank nanoparticles compared to the untreated control group. A moderate granulation of protoplasm of hepatic cells was observed in the livers from mice treated with cisplatin-loaded nanoparticles and blank nanoparticles, however, both the hepatic lobe and the portal hepatis maintained their normal architecture. The cisplatin-loaded PLGA-mPEG nanoparticles appeared to be effective at delaying tumor growth in HT 29 tumor-bearing SCID mice. The group of mice treated with cisplatin-loaded nanoparticles exhibited higher survival rate compared to the free cisplatin group. The results justify further evaluation of the in vivo antitumor efficacy of the PLGA-mPEG/cisplatin nanoparticles.     

Enhancement of natural killer cell function by titanocenes in mice bearing Ehrlich ascites tumour

In the present work, we studied the effects of two titanocenes, biscyclopentadienyldichlorotitanium IV, (DDCT) and its derivative, biscyclopentadienylditiocianatetitanium IV (BCDT), on the activity of natural killer (NK) cells in Ehrlich ascites tumour (EAT)-bearing BALB/c mice. In order to investigate a more direct effect of these compounds on NK cell function, we performed experiments with severe combined immunodeficiency (SCID) mice, which exhibit a normal NK cell response in the absence of T and B cells. The treatment consisted of intraperitoneal (i.p.) administration of 15 mg/kg/day of DDCT for 2 days or 10 mg/kg/day of BCDT for 3 days. In addition, to verify whether the effects produced by the titanocenes were compound specific or related to a direct antitumour effect, we also investigated the effects of a 3-day treatment with 100 mg/kg of cyclophosphamide cyclophosphamide on NK cell activity. Our results demonstrated that, in BALB/c and SCID mice, NK cell function declined to subnormal levels after inoculation of the tumour. In these animals, although treatment with DDCT and BCDT significantly enhanced NK cell function, only DDCT restored NK cell activity to normal values in all stages studied. Conversely, treatment with cyclophosphamide reduced NK cell function in nontumour bearing SCID mice and was also unable to restore the decreased NK activity of tumour-bearing SCID mice, thus demonstrating that the enhancement of NK cell function by titanocenes is compound specific. The same effect of cyclophosphamide was observed with BALB/c mice. In the present study, the up-modulatory effects of these two compounds on NK cell function reveal a new aspect of the mechanism of antitumoural action of titanocenes.     

Anti-tumor metastatic activity of beta-glucan purified from mutated Saccharomyces cerevisiae

The beta-glucans isolated from Saccharomyces cerevisiae (S. cerevisiae) enhance the innate immune system, but there is little evidence for its antitumor activity. To examine the antitumor and immunostimulating activities of beta-glucan (IS-2) purified from mutated S. cerevisiae, we made an experiment on innate immune response against metastasis of cancer cells by comparing with the beta-glucan from wild-type S. cerevisiae. In experimental lung metastasis of colon 26-M3.1 carcinoma or B16-BL6 melanoma cells, prophylactic administration of beta-glucan purified from mutated S. cerevisiae significantly inhibited lung metastasis in a dose-dependent manner. Furthermore, therapeutic administration of IS-2 also significantly inhibited the colon 26-M3.1 cell growth in mice. In an assay of liver and spleen metastasis produced by i.v. inoculation of L5178Y-ML25 lymphoma cells, IS-2 also significantly inhibited metastasis in CDF1 mice. Furthermore, pretreatment with IS-2 two days before tumor inoculation significantly prolonged the survival time of tumor-bearing mice. In an in vitro cytotoxicity analysis, IS-2 (up to 100 microg/ml) did not affect the growth of colon 26-M3.1 cells. In contrast, IS-2 enhanced splenocyte proliferating activity in a dose-dependent manner. Peritoneal macrophages stimulated with IS-2 produced various cytokines, such as IL-1beta, IFN-gamma, and IL-12. In addition, treatment with IS-2 (20 microg/mouse) induced tumoricidal activity of peritoneal macrophages against colon 26-M3.1 cells. In an assay for natural killer (NK) cell activity, IS-2 (20 microg/mouse, i.v.) significantly augmented NK cytotoxicity against Yac-1 tumor cells at 2 days after IS-2 treatment. The depletion of NK cells by injection of rabbit anti-asialo GM1 serum abolished the inhibitory effect of IS-2 on lung metastasis of colon 26-M3.1 cells. These data suggest that IS-2 inhibits tumor metastasis via activation of macrophages and NK cells.     

酪氨酸激酶抑制药SHR115723的药效学及药动学

目的对SHR115723进行初步体外和体内药效学、药动学研究,并与舒尼替尼进行比较,以了解SHR115723新药开发的潜力。方法用磺酰罗丹明B蛋白染色法检测药物对人脐静脉内皮细胞体外生长的抑制作用,用裸小鼠异体移植入结肠癌HT-29模型检测药物体内的抗肿瘤作用,应用高效液相色谱-紫外检测法进行大鼠体内的药动学研究。结果SHR115723和舒尼替尼对人脐静脉内皮细胞增殖的IC_(50)分别为(1.3±s 0.3)和(0.78±0.23)μmol·L~(-1)。SHR115723和舒尼替尼对裸小鼠异体移植人结肠癌HT-29生长具有明显的抑制作用。SHR115723的AUC和c_(max)高于舒尼替尼,但V_d较小。结论SHR115723具有明显的抗肿瘤作用,具有一定的新药开发潜力。