In-vivo antitumour effect of daunorubicin-GnRH-III derivative conjugates on colon carcinoma-bearing mice

Targeted cancer chemotherapy is a novel approach developed for the specific delivery of anticancer drugs. Tumour targeting can be achieved by combining a chemotherapeutic agent with a targeting moiety that recognizes tumour-specific or highly expressed receptors on cancer cells. We used the gonadotropin-releasing hormone-III (GnRH-III) as a targeting moiety to which the chemotherapeutic agent daunorubicin (Dau) was attached through an oxime bond either directly or by inserting a GFLG tetrapeptide spacer. The in-vivo toxicity of Dau-GnRH-III derivative conjugates was evaluated on healthy BDF-1 female mice, and their tumour growth inhibitory effect was determined on C26 murine and HT-29 human colon carcinoma-bearing mice. Both oxime bond-containing conjugates were well tolerated and exerted significant antitumour activity on C26 colon carcinoma-bearing mice at a dose of 30 mg Dau content in conjugate/kg body weight. Furthermore, the conjugates inhibited the tumour growth more than the free drug at a dose that was still not toxic. Similar tumour growth inhibitory effects were obtained on HT-29 human colon carcinoma-bearing mice using three treatments with 15 mg Dau content in conjugate/kg. The tumour growth inhibitions according to the tumour volume and the tumour weight were 44/41% and 58/50%, respectively. Considering the results, both of the investigated Dau-GnRH-III derivative conjugates were well tolerated and had significant antitumour effect on colon carcinoma-bearing mice.     

A selective plasmin inhibitor, trans-aminomethylcyclohexanecarbonyl-L-(O-picolyl)tyrosine-octylamide (YO-2), induces thymocyte apoptosis

The treatment of rat thymocytes with YO-2, a novel inhibitor of plasmin, resulted in an increase in DNA fragmentation. DNA fragmentation was also induced by another YO compounds such as YO-0, -3, -4 and -5. These YO compounds are the inhibitor of plasmin activity. On the other hand, YO-1, -6 and -8 that hardly inhibit plasmin activity had no effect on DNA fragmentation. Analysis of fragmented DNA from thymocytes treated with YO-2 by agarose gel electrophoresis revealed that the compound caused internucleosomal DNA fragmentation. In addition, judging from a laser scanning microscopy, annexin V-positive and propidium iodide-negative cells were increased by the treatment of the cells with the compound. Moreover, chromatin condensation was observed in thymocytes treated with the compound. These results demonstrated that YO-2 induces thymocyte apoptosis. There seemed to be some correlation between the apoptosis induced by YO compounds and their plasmin inhibitory effect. However, because the other protease inhibitors including pepstatin A, leupeptin, AEBSF, DFP and E-64-d did not affect DNA fragmentation, YO compounds are likely to have unique mechanism on plasmin or to show the effect on the other plasmin-like proteases. The plasmin inhibitory activity may have an important role in YO-2-induced apoptosis. Furthermore, the stimulations of caspase-8, -9 and -3-like activities were observed in thymocytes treated with YO-2. These results suggest that YO-2 induces thymocyte apoptosis via activation of caspase cascade.     

Methylglyoxal bis(butylamidinohydrazone) exhibits antitumor effect on human malignant melanoma cells but reduces the antitumor action of cisplatin.

The antitumor effect of a polyamine biosynthetic pathway inhibitor methylglyloxal bis(butylamidinohydrazone) (MGBB) on human malignant melanoma (HMG) cells and its combination effect with cisplatin were investigated. The growth of cultured HMG cells was inhibited in a dose dependent manner by either MGBB or cisplatin; complete inhibition of cell proliferation was attained with 5 micrograms/ml of MGBB or 50 micrograms/ml of cisplatin. Pretreatment of HMG cells with MGBB diminished the antitumor action of cisplatin. The cultured HMG cells were inoculated in nude mice and aliquots of the resulting solid tumors (HMG tumor) were transplanted. The growth of transplanted HMG tumors in mice was inhibited markedly by cisplatin (3.8 mg/kg) and moderately by MGBB (10 or 20 mg/kg). The in vivo antitumor effect of cisplatin was also reduced by combined treatment with MGBB.     

Antimetastatic effect of an immunomodulatory arabinomannan extracted from Mycobacterium tuberculosis strain Aoyama B,Z-100, through the production of interleukin-12

In this study, the role of interleukin (IL)-12 on the antimetastatic effect of Z-100 was investigated using wild-type C57BL/6 mice or IL-12p40 knockout (IL-12p40 KO) mice inoculated with highly metastatic B16F10 melanoma. When C57BL/6 mice were inoculated with B16F10 melanoma (2x10(5) cells/mouse i.v.), Z-100 (10 mg/kg i.p.) significantly suppressed the pulmonary metastasis of B16F10 melanoma 14 d after tumor inoculation. On the other hand, the antimetastatic effect of Z-100 was not observed in IL-12p40 KO mice inoculated with B16F10 melanoma. These results indicate that IL-12 is essentially required for the appearance of the antimetastatic effect of Z-100. Since helper T (Th) 2 cell responses have been reported to have a role in tumor metastasis, the regulatory effect of Z-100 on the immune balance of Th1/Th2 cell responses was investigated. In both C57BL/6 mice and IL-12p40 KO mice bearing B16F10 melanoma, Th1 cytokine production (IL-2, interferon-gamma) was significantly suppressed as compared with those in normal mice. On the other hand, Th2 cytokine production (IL-4, IL-10) in these mice was increased. The administration of Z-100 (10 mg/kg i.p.) in C57BL/6 mice bearing B16F10 melanoma improved the balance of Th1/Th2 cell responses from the Th2-dominant state to the normal state. However, the improvement of Th1/Th2 cell responses by Z-100 was not observed in IL-12p40 KO mice bearing the same tumors. In addition, Z-100 significantly increased IL-12 production by macrophages in a concentration-dependent manner, while Z-100 significantly decreased IL-10 production by these cells in vitro. These results suggested that up-regulation of IL-12 production and down-regulation of IL-10 production by Z-100 are related to the improvement of Th1/Th2 cell responses from the Th2-dominant state to the normal state, which resulted in suppression of tumor metastasis.     

三七总皂苷对B16黑色素瘤生长及转移的作用

目的观察三七总皂苷（PNS）对B16黑色素瘤生长及转移的作用,及其对B16黑色素瘤表达缝隙连接蛋白Connexin32的影响。方法实验采用B16黑色素瘤自发性肺转移模型,来观察PNS对B16黑色素瘤生长及转移的影响。免疫组织化学检测Connexin32在黑色素瘤原发灶的表达情况。结果（1）PNS对黑色素瘤生长有较好的抑制作用,其中PNS高剂量组抑瘤率可达50．85％。（2）与模型组相比PNS中、高剂量组能有效抑制黑色素瘤的肺转移,转移灶数量与对照组相比有明显减少。（3）免疫组织化学检测,发现PNS各用药组均能增强黑色素瘤原发灶细胞膜上Connexin32的表达。结论PNS能够抑制B16黑色素瘤的生长和转移,并能有效增强肿瘤细胞膜上Connexin32的表达。     

致弱RH株弓形虫抗小鼠B16黑色素瘤的实验研究

目的观察紫外线辐照致弱RH株弓形虫对小鼠体内黑色素瘤生长的抑制作用。方法1×10^7紫外线致弱RH株弓形虫速殖子经腹腔注射免疫C57BL/6J小鼠,7d后再次接种相同数量弓形虫,并在接种当天给小鼠荷瘤,在荷瘤后21d处死小鼠,测定小鼠肿瘤体积与质量,并检测脾细胞T细胞亚群和淋巴细胞杀伤活性。结果致弱弓形虫能够显著抑制肿瘤生长,实验组小鼠肿瘤体积与质量显著小于对照组（P〈0．05）,抑瘤率为52．09％。实验组小鼠脾细胞CD3^＋、CD4^＋、CD8^＋、CD4^＋／CD8^＋、NK细胞杀伤活性显著高于对照组（P〈0．05）。结论致弱免疫弓形虫可以抑制小鼠体内黑色素瘤生长。     

Preclinical antitumor activity and pharmacokinetics of methyl-2-benzimidazolecarbamate (FB642)

Methyl-2-benzimidazolecarbamate(carbendazim, FB642) is an anticancer agentthat induces apoptosis of cancer cells. Invitro, FB642 demonstrated potent antitumoractivity against both the murine B16melanoma (IC₅₀ = 8.5 m) andhuman HT-29 colon carcinoma(IC₅₀ = 9.5 m) cell lines. FB642was also highly active against both murinetumor models and human tumor xenografts atvarying doses and schedules. In the murineB16 melanoma model, T/C values > 200 wereobserved. In the human tumor xenograft,FB642 produced tumor growth inhibition ofgreater than 58% in five of the sevenxenograft models evaluated. Partial andcomplete tumor shrinkage was noted withFB642 against the MCF-7 breast tumor model.Pharmacokinetic studies in ratsdemonstrated that oral absorption of FB642was variable and may be saturated at the2000 mg/kg dose level since higher dosesfailed to produce a further increase in thearea under the time concentration curve. Toxicity of FB642 in vivo appeared to bedose-dependent. Lower doses in the range of2000–3000 mg/kg were better tolerated,while still preserving antitumor activity. Evaluation of FB642 in phase I clinicaltrials of adult patients with advancedmalignancies is currently ongoing.     

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.     

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.     

魟鱼软骨多糖对小鼠恶性黑色素移植瘤MMP-9表达的影响

目的:研究魟鱼软骨多糖(RCG)对小鼠恶性黑色素移植瘤基质金属蛋白酶-9(MMP-9)表达的影响。方法:体外培养黑色素瘤细胞(B16),接种B16细胞于C57BL/6小鼠右侧腋下部位,复制小鼠黑色素瘤模型。实验分为生理盐水(等容生理盐水)、环磷酰胺(CTX,60mg·kg-1)和魟鱼软骨多糖高、中、低剂量(700、300、100mg·kg-1)组,灌胃给药,每天1次,连续21d。观察肿瘤生长情况,计算原发瘤抑制率;采用Westernblot方法检测肿瘤组织中MMP-9的蛋白表达情况;采用RT-PCR方法检测MMP-9的基因表达情况。结果:与生理盐水组比较,魟鱼软骨多糖高、中、低剂量组小鼠原发瘤抑制率显著升高(P<0.01);魟鱼软骨多糖高、中、低剂量组MMP-9蛋白表达、基因表达显著降低(P<0.01)。结论:魟鱼软骨多糖能明显抑制小鼠黑色素瘤原发瘤的生长,可能与其抑制肿瘤MMP-9的蛋白表达和MMP-9mRNA的表达有关。     

Morphine analgesia suppresses tumor growth and metastasis in a mouse model of cancer pain produced by orthotopic tumor inoculation

The present study was conducted to clarify whether relief from cancer pain by morphine would suppress tumor growth and metastasis. When given orthotopic inoculation of B16-BL6 melanoma cells into the hind paw, C57BL/6 mice showed moderate and marked hyperalgesia on days 7-10 and from day 14 post-inoculation, respectively. The volume of inoculated hind paw was increased exponentially as a function of time from day 8 post-inoculation, a phenomena being due to melanoma growth. Lung metastasis was apparent after day 12 post-inoculation. On day 16 post-inoculation, the hyperalgesia was completely inhibited by subcutaneous injection of morphine hydrochloride (5 and 10 mg/kg). The tumor growth and lung metastasis were markedly inhibited by repeated administration of morphine (5 and 10 mg/kg daily for 6 days) and also by the neurectomy of sciatic nerve innervating the inoculated region. The results suggest that relief from cancer pain by morphine inhibits tumor growth and metastasis.     

Antimetastatic activity of acteoside,a phenylethanoid glycoside

We examined the antimetastatic effect of acteoside, a phenylethanoid glycoside widely distributed in the plant kingdom, on lung metastasis using a mouse model injected with B16 melanoma cells intravenously. Male C57BL/6 mice were injected intravenously with 2 x 10(5) of B16 melanoma cells, while acteoside at a dose of 50 mg/kg was administered intraperitoneally every other day from 13 d before B16 melanoma cell injection until all mice had succumbed to the metastatic tumor burden in the lung. Administration of acteoside prolonged survival time significantly and the average survival time was 63.3 +/- 3.4d compared with 52.1 +/- 2.5d in control mice. This result suggests that acteoside showed suppressive effect on lung metastasis of B16 melanoma cells.     

Glycine inhibits melanogenesis in vitro and causes hypopigmentation in vivo

The simplest amino acid, glycine, is important in protein composition and plays a significant role in numerous physiological events in mammals. Despite the inhibitory effect of glycine on spontaneous melanogenesis in B16F0 melanoma cells, the details of the underlying mechanisms remain unknown. The present study was conducted to investigate the further effects and the mechanisms of inhibitory effect of glycine on melanogenesis using B16F0 melanoma cells and hair follicle melanogenesis in C57BL/6J mice. Treatment with glycine (1-16 mM) for 72 h inhibited alpha-melanocyte stimulating hormone (alpha-MSH)-induced melanogenesis in a concentration-dependent manner without any effects on cell proliferation in B16F0 melanoma cells. Treatment with kojic acid (2.5 mM) for 72 h also inhibited alpha-MSH-induced melanogenesis in B16F0 melanoma cells. The highest dose of glycine inhibited the alpha-MSH-induced increment of tyrosinase protein levels in B16F0 melanoma cells. In hair follicle melanogenesis in C57BL/6J mice, treatment with glycine (1250 or 2500 mg/kg, i.p.) for 5 d prevented the decrement of L* and C* values and inhibited the increment of tyrosinase protein levels and melanin content within the skin. Treatment with hydroquinone (100 mg/kg, i.p.) for 5 d had a similar hypopigmenting effect to that of high dose glycine. These results suggest that glycine has an inhibitory effect on melanogenesis that is mediated by down-regulation of tyrosinase protein levels, leading to a hypopigmenting effect in C57BL/6J mice.     

Antimetastatic activity of MONCPT in preclinical melanoma mice model

Previous study demonstrated that MONCPT, a topoisomerase I inhibitor, exhibited potent anti-proliferation and anti-angiogenesis activity in vitro and in vivo. In this study, we report the efficacy of MONCPT against the development of melanoma metastasis by an intravenous injection of green fluorescent protein-transfected mice melanoma carcinoma (B16F10-GFP) cells in C57BL/6 mice. MONCPT (2.0, 5.0 and 12.5 mg/kg/2 days) markedly decreased B16F10-GFP pulmonary metastases by 12.8%, 53.1% and 76.3%, respectively; whereas higher doses of MONCPT (31.0 mg/kg/2 days) significantly inhibited the tumor growth of B16F10 xenograft model. In the in vitro experiment, MONCPT suppressed the B16F10-GFP cell invasion and migration without affecting cell survival. Further studies demonstrated that MONCPT decreased the secretion of matrix metalloproteinase (MMP)-9 and VEGF, and reduced the protein expression of HIF-1α as well as the phosphorylation level of ERK in B16F10-GFP cells. These in vivo and in vitro results indicate that MONCPT possesses both the potent antimetastatic ability and the tumor growth-inhibition activity, and the dual function promises MONCPT as a potential therapeutic agent for tumor metastasis and tumor growth of melanoma carcinoma.     

铂类抗癌新药双环铂的体内外抗肿瘤活性

目的观察铂类抗癌新药双环铂的体内外抗肿瘤活性及其对细胞周期的影响。方法MTT法观察双环铂对人肿瘤细胞增殖的抑制作用;小鼠动物肿瘤模型观察双环铂对肿瘤的体内抑制作用;碘化丙锭PI染色流式细胞术分析药物所致人卵巢癌细胞A2780细胞的周期变化。结果双环铂于体外抑制多种人肿瘤细胞增殖,体内抑制小鼠肉瘤S180、肝癌Heps及黑色素瘤B16的生长,并导致A2780细胞S期细胞明显增加及G2/M期细胞少许增加。结论双环铂具有明显的体内外抗肿瘤活性,并影响肿瘤细胞的细胞周期分布。     

应用中空纤维测定法评价藤甲酰苷对人癌细胞生长的抑制作用

目的应用中空纤维测定法评价藤甲酰苷（garcinia glycosides,GG）对8种人癌细胞的体内生长的抑制作用,通过裸鼠体内异位移植瘤实验,验证中空纤维测定法在抗肿瘤药效学研究中的可靠性。方法采用中空纤维测定法,将载有肿瘤细胞的中空纤维管植入NOD/SCID小鼠背部皮下,给药结束后取出中空纤维管,应用二苯基溴化四氮唑蓝（MTT）比色法检测GG对各种肿瘤细胞在体内的抑瘤率;选取HL-60及B16人癌细胞,异位移植于BALb/c裸鼠右下肢外侧皮下,以环磷酰胺（CTX）为阳性对照,各组连续给药10 d,于给药结束24 h后解剖小鼠,取出瘤块,计算CTX及GG的抑瘤率。结果应用中空纤维测定法及裸鼠体内异位移植瘤法测得GG高剂量组8 mg/（kg·d）、中剂量组4 mg/（kg·d）能明显抑制HL-60及B16人癌细胞在裸鼠体内的生长,实验测得结果与溶剂对照组比较,有显著性差异（P〈0.01）。结论应用中空纤维测定法测定样品GG对肿瘤细胞的生长抑制作用,实验结果与裸鼠体内异位移植瘤实验结果基本一致。该模型节约成本、效率提高、实验结果准确可靠,为GG的后续研究提供了指导和可靠证据。     

Inhibitory effect of antidepressants on B16F10 melanoma tumor growth

BackgroundAntidepressant drugs, like fluoxetine, a selective serotonin reuptake inhibitor, desipramine, a nonselective noradrenaline reuptake inhibitor, and mirtazapine, an antagonist of noradrenaline α₂ auto- and heteroreceptors, are widely used for the treatment of depressive symptoms in cancer patients. Since these antidepressants have different activities targeting the immune system, they might also modulate tumor growth in cancer patients.MethodsIn the present study, we investigated the effects of administration of antidepressant drugs: fluoxetine, desipramine and mirtazapine on B16F10 melanoma tumor growth. These drugs were administered intraperitoneally (ip) for 17 days after subcutaneous injection of B16F10 melanoma cells to male C57BL/6J mice.ResultsFluoxetine significantly inhibited melanoma solid tumor growth and desipramine tended to decrease this parameter whereas mirtazapine had no effect.ConclusionThe inhibitory effect of fluoxetine on melanoma growth was associated with an increased mitogen-induced T cell proliferation which may at least partly participate in the mechanism of the antitumor effect of this antidepressant. It appears that the inhibitory effect of fluoxetine on tumor growth is not related with changes in cytokine levels except for IL-10.     

MC002对A-549、HT-1080荷瘤小鼠肿瘤生长抑制作用的研究

目的MC002是雷公藤内酯醇的半合成衍生物,本实验主要观察和评价MC002对人肺腺癌A-549、人纤维肉瘤HT-1080小鼠模型的肿瘤抑制作用。方法用Balb/C裸小鼠接种人肺腺癌A-549瘤株和人纤维肉瘤HT-1080瘤株造成小鼠肿瘤模型,以MC002对荷瘤小鼠的相对肿瘤增殖率、瘤重、抑瘤率为指标评价MC002对小鼠的抑瘤作用。结果对于两种不同瘤株,MC002各剂量组体积明显小于模型对照组,瘤重均降低,在大剂量组1.5(mg.kg-1)时T/C%在给药几次后均小于60%(P<0.05),且具有量效关系。结论MC002能有效抑制人肺腺癌A-549、人纤维肉瘤HT-1080荷瘤小鼠体内肿瘤生长。MC002有可能发展成为一种新型抗癌药。     

Age-dependent stimulatory effect of desipramine and fluoxetine pretreatment on metastasis formation by B16F10 melanoma in male C57BL/6 mice

Although recent data may provide theoretical support for the preventive use of antidepressants in cancer patients, so far no study has demonstrated the clinical benefits of such strategies in the general population of cancer patients [39, 41]. Moreover, an association between antidepressant use and the risk of tumor promotion could neither be excluded nor established.The aim of this study was to compare the effect of desipramine (a tricyclic antidepressant, TCA) and fluoxetine (a selective serotonin reuptake inhibitor, SSRI) on tumor growth of the mouse B16F10 transplanted melanoma in “young” 6–9 month old and “aged” 18–23 month old male C57BL/6 mice. Drugs were administered daily at a dose of 10 mg/kg, ip, for two weeks and tumor cells were inoculated 2 h after the last antidepressant administration. Control animals were treated with saline. Tumor growth was significantly slower in aged than in young saline-treated control animals. Pretreatment with desipramine dramatically promoted metastasis formation and increased mortality rate but inhibited primary tumor growth in young males. On the other hand, both antidepressants increased primary tumor growth in aged animals, whereas metastasis was only moderately promoted. To determine the effect of antidepressant drug pretreatment and tumor progress on some parameters of cell-mediated immunity (proliferative activity and cytokine production by splenocytes) and angiogenesis, vascular endothelial growth factor (VEGF) and metalloproteinase (MMP)-9 plasma levels were established. The prometastatic effect of desipramine in young animals was connected with an increase of VEGF and MMP-9 plasma levels.