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1.
Psoriasis is a common skin disease which is characterised by the proliferation and abnormal differentiation of keratinocytes, coupled with complex immune disturbances. The beneficial effects of vitamin D derivatives in this disease are due to their capacity to inhibit proliferation, their ability to induce normal differentiation and their immunomodulatory properties. Since the systemic administration of these compounds is limited by their effect on calcium metabolism, topical preparations have become available in most countries. Topical calcipotriol and/or tacalcitol are now considered as first-line treatment for mild-to-moderate psoriasis and can be taken in combination with other systemic therapies in more severe cases of the disease. Novel orally active vitamin D analogues, with minimal calcitropic effercts, are, however, required for more effective treatment.  相似文献   

2.
Calcipotriol (MC903) is a novel vitamin D analogue which effects cellular differentiation and proliferation in vitro and has reduced effects on calcium metabolism in vivo. In the present study its in vitro activity was evaluated using the MCF-7 breast cancer cell line, and its effects on calcium metabolism and mammary tumour growth were measured in vivo in adult female rats. Calcipotriol was compared to the natural metabolite of vitamin D3, 1 alpha,25-dihydroxycholecalciferol [1,25(OH)2D3] and its synthetic analogue 1 alpha hydroxycholecalciferol [1 alpha(OH)D3]. Both calcipotriol and 1,25(OH)2D3 produced significant inhibition of MCF-7 cell proliferation at a concentration of 5 x 10(-11) M. Intraperitoneal administration of calcipotriol to normal female rats showed that the analogue was 100-200 times less active than 1,25(OH)2D3 in raising serum calcium concentration and urinary calcium excretion. Anti-tumour activity of the vitamin D analogues was investigated in vivo using the nitrosomethylurea-induced rat mammary tumor model. Rats, maintained on a low calcium diet, were treated with 1 alpha(OH)D3 (0.25 and 1.25 micrograms/kg). Both doses produced a response rate of 25% but hypercalcaemia developed. Treatment with calcipotriol (50 micrograms/kg) of rats maintained on a normal laboratory diet caused inhibition of tumour progression (response rate 17%) without the development of severe hypercalcaemia. This study supports the concept that vitamin D derivatives may inhibit breast cancer cell proliferation in vivo.  相似文献   

3.
4.
Berberine is an isoquinoline plant alkaloid with a long history of being used for the treatment of many diseases in Chinese herbal medicine. Berberine has a wide range of biochemical and pharmacological effects, including antitumor activities, but its mechanism of action is not clearly understood. In this study, we investigated that the relationship between the antiproliferative activities of berberine and the apoptotic pathway associated with its molecular mechanism of action in human glioblastoma T98G cells. Berberine treatment of T98G cell lines inhibited cell proliferation and induced cell death in a dose (50-200 microg/ml) dependent manner with an IC50 value of 134 microg/ml, which was associated with an increase in G1 arrest. Western blot analysis showed that the berberine-induced G1 arrest was mediated through the increased expression of P27 and the decreased expression of cyclin-dependent kinase (CDK) 2, CDK4, cyclin D, and cyclin E proteins. Berberine treatment also markedly enhanced apoptosis in T98G cells through the induction of a higher ratio of the Bax/Bcl-2 proteins, the disruption of mitochondrial membrane potential, and the activation of procaspase-9, caspase-9, caspase-3, and poly(ADP-ribose) polymerase (PARP). Berberine can inhibit T98G cell proliferation by inducing G1 arrest and apoptosis. These results demonstrate that the berberine-induced apoptosis of T98G cells is primarily mediated through the mitochondrial/caspases-dependent pathway.  相似文献   

5.
Berberine has a wide range of biochemical and pharmacologic effects, including antitumor activity, but the mechanisms involved in berberine-induced apoptosis remain unclear. The purpose of the present study was to investigate the changes in oxidative stress and endoplasmic reticulum (ER)-related molecules, which are closely associated with cell death-signaling transduction pathways, in human glioblastoma T98G cells treated with berberine. Berberine significantly decreased the cell viability of T98G cells in a dose-dependent manner. Berberine increased the production of reactive oxygen species (ROS) and level of intracellular Ca(2+). Berberine induced ER stress as evidenced by the detection of ER stress-associated molecules such as phosphorylated protein kinase-like ER kinase, eukaryotic translation initiation factor-2α, glucose-regulated protein 78/immunoglobulin heavy chain-binding protein, and CCAAT/enhancer-binding protein (C/EBP)-homologous protein/growth arrest and DNA damage-inducible gene 153, which was associated with the activation of caspase-3. Furthermore, the administration of the antioxidants, N-acetylcysteine and glutathione, reversed berberine-induced apoptosis. Berberine also markedly enhanced apoptosis in T98G cells through the induction of a higher ratio of Bax/Bcl-2 proteins, disruption of the mitochondrial membrane potential, activation of caspase-9 and -3, and cleavage of the poly(ADP-ribose) polymerase (PARP). The inhibition of ER stress using salubrinal led to an increased the level of Bcl-2, whereas the level of Bax, cleavage of procaspase-9 and -3, and PARP were decreased when compared with cells treated with berberine alone, indicating that berberine-induced apoptosis is associated with mitochondrial dysfunction. These results demonstrate that berberine induces apoptosis via ER stress through the elevation of ROS and mitochondrial-dependent pathway in human glioblastoma T98G cells.  相似文献   

6.
The active form of vitamin D3, calcitriol, is a potent antiproliferative compound. However, when effective antitumor doses of calcitriol are used, hypercalcemic effects are observed, thus blocking its therapeutic application. To overcome this problem, structural analogues have been designed with the aim of retaining or even increasing the antitumor effects while decreasing its calcemic activity. This report aims at gaining insights into the structure–activity relationships of the novel oxolane‐containing analogue, AM‐27, recently synthesized. We herein demonstrate that this compound has antiproliferative and antimigratory effects in squamous cell carcinoma, glioblastoma, and breast cancer cell lines. Analyses of the mechanisms underlying the AM‐27 effects on cell viability revealed induction of apoptosis by the analogue. Importantly, nonmalignant cell lines were little or not affected by the compound. In addition, the analogue did not produce hypercalcemia in mice. Also, in silico studies involving docking and molecular dynamics techniques showed that AM‐27 is able to bind to the human vitamin D receptor with a higher affinity than the natural ligand calcitriol, a feature that is mostly derived from an electrostatic interaction pattern. Altogether, the proapoptotic effect observed in cancer cells, the lack of calcemic activity in mice, and the differential effects in normal cells suggest the potential of AM‐27 as a therapeutic compound for cancer treatment.  相似文献   

7.
Glioblastoma multiforme (GBM) is the most malignant form of brain tumors with dismal prognosis despite treatment by surgery combined with radiotherapy and chemotherapy. The neuropeptide Substance P (SP) is the physiological ligand of the neurokinin‐1 receptor, which is highly expressed in glioblastoma cells. Thus, SP represents a potential ligand for targeted alpha therapy. In this study, a protocol for the synthesis of SP labeled with the alpha emitter 225Ac was developed and binding affinity properties were determined. The effects of 225Ac‐DOTA‐SP were investigated on human glioblastoma cell lines (T98G, U87MG, U138MG) as well as GBM stem cells. A significant dose‐dependent reduction in cell viability was detected up to 6 days after treatment. Also, colony‐forming capacity was inhibited at the lower doses tested. In comparison, treatment with the conventional agent temozolomide showed higher cell viability and colony‐forming capacity. 225Ac‐DOTA‐SP treatment caused induction of late apoptosis pathways. Cells were arrested to G2/M‐phase upon treatment. Increasing doses and treatment time caused additional S‐phase arrest. Similar results were obtained using human glioblastoma stem cells, known to show radioresistance. Our data suggest that 225Ac‐DOTA‐SP is a promising compound for treatment of GBM.  相似文献   

8.
AIM: To examine the effect of a novel peroxisome proliferator-activated receptor (PPAR) α/γ dual agonist TZD 18 on cell proliferation and apoptosis in human glioblastoma T98G cells and its possible mechanism. METHODS: RTPCR, MTT, TUNEL, Flow cytometry, and Western blot analysis were employed. RESULTS: TZD18 inhibited the growth of T98G cells in a concentration-dependent manner, which was associated with a GI to S cell cycle arrest. Besides, significant apoptosis was induced after treatment with a non-toxic dose of TZD 18. During the process, the expression of Bcl-2 protein was down-regulated, while that of Bax and p27^kip proteins was up-regulated, and the activity of caspase-3 was elevated. However, this effect appeared to be PPARα and PPARγ/independent since their antagonists could not reverse this effect. CONCLUSIONS: TZD18, a novel PPARα/γ dual agonist, inhibited cell growth and induce apoptosis in human glioblastoma T98G cells in vitro, indicating a therapeutic potential for TZD18 in the treatment of glioblastoma.  相似文献   

9.
Hispolon is a polyphenolic compound isolated from Phellinus linteus which exhibits antitumor activity. Here, we explored the effects of hispolon on human glioblastoma cells U87MG. Cell viability was examined by MTT assay. Growth was investigated by incubating cells with various concentrations of hispolon (25 and 50 µM) for 24, 48 or 72 h and daily cell count. Cell cycle and apoptosis assay were assessed by flow cytometry. Hispolon decreased cell viability in a dose‐ and time‐dependent manner. The cell cycle distribution showed that hispolon enhanced the accumulation of the cells in G2/M phase. Hispolon decreased the expression of G1–S transition‐related protein cyclin D4 but increased the expression of CDK inhibitor p21. Additionally, hispolon enhanced the expression of p53. Moreover, hispolon treatment was effective on U87MG cells in inhibiting cell viability and inducing cell apoptosis. Our results indicate that hispolon inhibits the cell viability, induces G2/M cell cycle arrest and apoptosis in glioblastoma U87MG cells, and p53 should play a role in hispolon‐mediated antitumor activity.  相似文献   

10.
Abstract: Calcipotriol is a novel vitamin D3 analogue developed for topical treatment of psoriasis. Calcipotriol is believed to act via regulation of cell proliferation and differentiation. In this respect calcipotriol is as potent as 1α,25(OH)2D3, the physiologically active form of vitamin D3, but its calcaemic activity in vivo is 100 to 200 times lower. In the present investigation, the effects of calcipotriol on cell growth regulation in vitro and on calcium metabolism in vivo were compared to those exerted by a number of metabolites and analogues of vitamin D3. Besides 1α,25(OH)2D3, these included the two physiologically occurring metabolites 25(OH)D3 and 24,25(OH)2D3, and the two synthetic analogues 1α(OH)D3 and 1α,24(OH)2D3. 25(OH)D3 and 24,25(OH)2D3 were shown to be inactive both in vitro and in vivo. 1α(OH)D3 was found to have a low biological activity in vitro, but was highly calcaemic in vivo after biotransformation to 1α,25(OH)2D3. Calcipotriol, 1α,24(OH)2D3 and 1α,25(OH)2D3 were all three potent regulators of cell proliferation and differentiation in vitro. In vivo, only calcipotriol showed a greatly reduced calcaemic activity after both oral and intravenous administration. It is concluded that calcipotriol, with a reduced risk of inducing calcaemic side-effects upon absorption from the skin, possesses a favourable therapeutic profile for topical treatment of hyperproliferative diseases.  相似文献   

11.
We describe here the effects of three drugs that are either approved or have the potential for treating multiple sclerosis (MS) patients through the in vitro activities of human natural killer (NK) cells and dendritic cells (DCs). Our results indicate that 1,25(OH)2D3, the biologically active metabolite vitamin D3, calcipotriol and FTY720 augment IL-2-activated NK cell lysis of K562 and RAJI tumor cell lines as well as immature (i) and mature (m) DCs, with variable efficacies. These results are corroborated with the ability of the drugs to up-regulate the expression of NK cytotoxicity receptors NKp30 and NKp44, as well as NKG2D on the surfaces of NK cells. Also, they down-regulate the expression of the killer inhibitory receptor CD158. The three drugs down-regulate the expression of CCR6 on the surface of iDCs, whereas vitamin D3 and calcipotriol tend to up-regulate the expression of CCR7 on mDCs, suggesting that they may influence the migration of DCs into the lymph nodes. Finally, vitamin D3, calcipotriol and FTY720 enhance NK17/NK1 cell lysis of K562 cells, suggesting that a possible mechanism of action for these drugs is via activating these newly described cells. In conclusion, our results show novel mechanisms of action for vitamin D3, calcipotriol and FTY720 on cells of the innate immune system.  相似文献   

12.
Glioblastoma multiforme (GBM), a malignancy characterized by its rapid progression, presents a lower risk of occurrence in women during their reproductive years. Necrosis of brain tissue during tumor invasion releases free lipids, and therefore might release contaminants stored in phospholipid-rich neuronal tissue. This study assesses the growth response of two human glioblastoma cell lines, T98G and U138-MG, treated with environmental chemicals known or likely to persist within the brain. Persistent chlorinated pesticides, industrial contaminants, persistent perfluorinated chemicals, and steroid hormones were assayed over a range of concentrations. Although cytotoxic effects were seen in both T98G and U138-MG cells, proliferative responses occurred only in the T98G cell line. Dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethylene (DDE), and polychlorinated biphenyl (PCB) 153 were cytotoxic in both lines at 5000 nM. Perfluorodecanoic acid (PFDA), perfluorooctane sulfonate (PFOS), and testosterone stimulated proliferation in the T98G cells at 500, 1000, and 1000 nM, respectively. However, a perfluorinated salt (ammonium perfluorooctanoate; C8) and a weak androgen (dihydroepiandrosterone; DHEA) did not affect relative cell number in this GBM line, suggesting the proliferative effect is not through the activation of an androgen receptor. Exposure to environmental chemicals that result in a mitogenic response may increase the rate of glioblastoma tumor growth and result in the development of more aggressive forms of GBM tumors.  相似文献   

13.
Within the past decade it has been shown that psoriasis can be treated topically with analogs of vitamin-D3. Impaired differentiation and increased proliferation of keratinocytes are key features in psoriatic lesions together with a local activation of T lymphocytes. Evidence has accumulated showing that analogs of vitamin D3 increase differentiation and inhibit proliferation of keratinocytes. Therefore, analogs of vitamin D3 have been investigated in a number of trials showing improvement of psoriasis. It has been shown that vitamin D analogs are better than their vehicle and show the same potency as potent topical steroids. However, vitamin D analogs have been proven efficacious and without side effects also when used on long term basis. Vitamin D analogs can be used both as monotherapy and in combination topical steroids, UVB, PUVA, retinoids and cysclosporine. The vitamin D3 analog calcipotriol has been investigated in most detail and is available as an ointment, a creme and as a scalp solutation. From clinical studies involving thousands of patients, it can be concluded that calcipotriol is efficacious, safe, well tolerated and can be used on a long term basis. Other analogs are available, however, these analogs have not been studied in greater details yet.  相似文献   

14.
The novel analogue of 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3), 1,24(OH)2-22-ene-24-cyclopropyl D3 (calcipotriol, MC903), exhibits similar effects on cell proliferation and cell differentiation in a newly established human megakaryoblastic leukemia cell line (HIMeg). MC903 was found to inhibit cell proliferation and induce cell differentiation in a liquid culture system at concentrations comparable to those of 1,25(OH)2 D3. Colony formation assay showed that MC903 or 1,25(OH)2 D3 markedly diminished the colony-forming ability of HIMeg cells at concentrations of 10(-6) M to 10(-10) M. Cell cycle analysis demonstrated that, as seen with 1,25(OH)2 D3, MC903 also altered the cell cycle distribution; the fraction of cells in G0 + G1 increased while those in S and G2 + M decreased. It can be concluded from these findings that 1,25(OH)2 D3 and its analogue MC903 have approximately equipotent effects on cells of megakaryoblastic lineage and are potentially useful in studying the cellular processes that are responsible for megakaryocytopoiesis.  相似文献   

15.
目的 探讨微小RNA-568(miR-568)对胶质母细胞瘤细胞增殖和凋亡的影响及作用机制.方法 培养正常星形胶质细胞HA1800及胶质母细胞瘤细胞系(U251、T98G和SHG44)购自中国科学院上海细胞库,qRT-PCR检测细胞中miR-568和醛酮还原酶家族1成员B10(AKR1B10)mRNA表达,蛋白质印迹法...  相似文献   

16.
To date, high mortality in women due to malignancy breast cancer related to the metastasis to the bone is a significant challenge. As, magnetic nanoparticles (MNPs) conjugated with the biocompatible polymers was employed for the delivery of some hydrophobic anticancer agents, the main aim of the current research was to assess whether cisplatin‐loaded MNPs enhanced the anticancer effect of free cisplatin in breast cancer cells. MNPs decorated with PEG were synthesized by an improved coprecipitation technique, and then cisplatin was loaded onto the MNPs via a simple mixing method. Afterward, its morphology, size, chemical structure, magnetic property, hydrodynamic diameter, zeta potential, and crystal structure were characterized by scanning and transmittance electron microscopy, Fourier transforms infrared spectroscopy, vibrating sample magnetometer, dynamic light scattering, and X‐ray powder diffraction and flame atomic absorption spectroscopy respectively. Additionally, the effects of cisplatin and MNPs‐PEG‐cisplatin on viability, migration and adhesion capacity of T47D cells were investigated by evaluating α2‐integrin and β1‐integrin; mRNAs were assessed by real‐time RT‐PCR. Consequently, the in vitro assay results showed a considerable dose‐dependent inhibitory effect of cisplatin and MNPs‐PEG‐cisplatin on proliferation, migration, and adhesion of T47D cells. Finally, current research was shown that MNPs‐PEG‐cisplatin strongly increased anticancer effects compared with free cisplatin in the T47D cell line.  相似文献   

17.
We describe 3 cases of psoriatic patients who developed a severe eczematous eruption after the use of calcipotriol ointment. For all of them, the dermatitis recovered after the suspension of the calcipotriol ointment and topical application of corticosteroids. We performed patch tests with the standard series of SIDAPA (Italian Society of Environmental, Occupational and Allergological Dermatology), with an integrative series of vehicles and preservatives, with the commercial ointment containing calcipotriol, with its excipients and, finally, with a series of diluted calcipotriol in isopropanol and petrolatum. They all revealed a strong allergic reaction to calcipotriol and also to its dilution in isopropanol (for all patients) and in petrolatum (only one patient). It is interesting to underline that the reactions always occurred on the legs, even if the patients had applied the ointment elsewhere. We can hypothesize that the venom stasis dermatitis of the legs, associated with xerosis, may have favored the penetration of the drug through the skin, increasing the risk of allergic contact sensitization. Finally, cross-reactivity to other vitamin D3 analogue, tacalcitol, and calcitriol was excluded.  相似文献   

18.
Analogs of 1,25-dihydroxyvitamin D3 with a reversed configuration at C-1 or C-24 and E or Z geometry of the double bond at C-22 in the side chain or at C-5 in the triene system were examined for their antiproliferative activity in vitro against a spectrum of various human cancer cell lines. The analogs coded PRI-2201 (calcipotriol), PRI-2202 and PRI-2205, such as calcitriol and tacalcitol (used as a referential agents), revealed antiproliferative activity against human HL-60, HL-60/MX2, MCF-7, T47D, SCC-25 and mouse WEHI-3 cancer cell lines. The toxicity studies in vivo showed that PRI-2202 and PRI-2205 are less toxic than referential agents. Even at total doses of 2.5-5.0 mg/kg distributed during 5 successive days, no changes in body weight were observed. Calcitriol and tacalcitol showed toxicity in the same protocol at 100 times lower doses. Calcipotriol was lethal to all mice after administration of a total dose of 5.0 mg/kg. The analog PRI-2205 appeared to be more active in mouse Levis lung cancer tumor growth inhibition than calcitriol, calcipotriol or PRI-2202. This analog did not reveal calcemic activity at doses which inhibit tumor growth in vivo nor at higher doses.  相似文献   

19.
Psoriasis is a genetically determined disease characterized by hyperproliferation and disordered maturation of the epidermis. Th1 lymphocytes are implicated in its pathogenesis. The vitamin D receptor (VDR) is a candidate modifying gene, having immunosuppressive effects and being involved in anti-proliferative and pro-differentiation pathways in keratinocytes. There is suggestive evidence that the A allele of the A-1012G polymorphism is associated with down-regulation of the Th1 response, via GATA-3. The F and T alleles of Fok1 and Taq1 have been associated with increased VDR activity. The present study aimed to test the hypothesis that the A allele of A-1012G is protective for occurrence and severity of psoriasis and enhances therapeutic response to vitamin D analogues and that these effects would be additive to those of Fok1 and Taq1. The study group comprised 206 psoriasis patients who had received topical calcipotriol treatment and 80 controls. There was no significant linkage disequilibrium between any pair of the three polymorphic sites (P=0.3-0.8). The A, F and T alleles were positively associated with calcipotriol response: AA genotype (compared to AG/GG), odds ratio (OR)=2.18 (P=0.04); TT, OR=1.97 (P=0.03); AAFF genotype combination, OR=4.11 (P=0.03); AATT, OR=5.64 (P=0.005); and FFTT, OR=3.22 (P=0.01). Comparing patients without, to patients with, a family history of psoriasis, the A allele was under represented (P=0.01) and the AAFF genotype combination even more so (compared to residual genotypes) (OR=0.24; P=0.005). AAFF was also under-represented in patients without a family history compared to controls (OR=0.31; P=0.04). There were no associations of family history with Fok1 and Taq1. There were no associations of severity of psoriasis with any polymorphism. In conclusion, the A-1012G, Fok1 and Taq1 VDR polymorphisms were associated with response to calcipotriol. A-1012G and Fok1 were associated with susceptibility to non-familial psoriasis.  相似文献   

20.
Targeting cell surface receptors with immunotoxins provides a novel, unique and highly potent treatment against cancers. A high expression of interleukin-13 (IL13) receptor α2 (IL13Rα2) has been reported in different types of cancers including glioblastoma multiforme (GBM). In this paper, to target IL13Rα2 on GBM cells, a fusion protein was generated comprising human IL13 and staphylococcal enterotoxin B (SEB), termed IL13-linker-SEB. The fusion protein was cloned into pET28a(+) and expressed in Escherichia coli strain BL21 (DE3); U251 (IL13Rα2-positive) and T98G (IL13Rα2-negative) GBM cell lines were employed and the functional activity of IL13-linker-SEB was evaluated by cell ELISA, cytotoxicity (MTT and LDH), apoptosis (flow cytometry and caspase-3 activity), adhesion, scratch and RT-PCR tests. SEB and chemotherapeutic drugs were employed to be compared to IL13-linker-SEB function. The IL13-linker-SEB exhibited higher binding affinity and cytotoxicity compared to SEB on U251 cells, although both recombinant proteins had shown similar behavior regarding T98G cells. Furthermore, the highest induction of apoptosis was observed in U251 cells treated with IL13-linker-SEB which was confirmed by Bax/Bcl-2 ratio. The expression of MMP2, MMP9 and VEGFR2 in U251 cells experienced a significant reduction after treatment with IL13-linker-SEB compared to SEB and T98G treated cells. The data showed that IL13-linker-SEB can be considered as a novel potential agent for GBM treatment; however, further research is needed to investigate the efficacy.  相似文献   

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