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351.
Summary Estrogen-receptor binding moieties were introduced into Pt(II) complexes in order to facilitate the selective transport into cancer cells. Estradiol esters of 2,3-diaminopropionic acid and estradiol ethers of 1,2-diamino-2-methyl-3-(p-hydroxyphenyl)propane were attached to Pt(II) complexes. The antitumor activity of the compounds was tested towards the human mammary carcinoma cell lines MDA-MB 231 and MCF-7, respectively, and the estrogen-receptor binding affinity of the Pt(II) complexes was determined. The steroidal Pt(II) complexes gave a maximum growth inhibition of 80% and a maximum estrogen-receptor binding affinity of 5.18. 相似文献
352.
经VP-16 大剂量短暂冲击加递增低浓度诱导方法建立了鼻咽癌耐药细胞亚系LCE/VP.用RT-PCR和FCM 免疫荧光法检测了耐药基因MRP和m dr1 在m RNA 水平和蛋白质水平的表达,并用MTT 法测定了LCE/VP对9 种化疗药物的敏感试验. 结果发现LCE/VP细胞MRP和m dr1 在m RNA水平均有表达,且前者明显高于后者,蛋白质水平的表达情况与m RNA 水平相一致;LCE/VP对9 种化疗药物中的6 种药物敏感程度均有不同倍数的增加. 这表明LCE/VP呈典型的MDR表型,并有耐药基因MRP和m dr1 的共表达,其中MRP起主要作用 相似文献
353.
Imaoka I Sugimura K Masui T Takehara Y Ichijo K Naito M 《Magnetic resonance imaging》1999,17(10):653-1455
The objective of the study was to assess the usefulness of magnetic resonance (MR) imaging in distinguishing malignant from benign conditions in patients with an abnormal uterine cavity. Fifty-four patients that were suspected of having abnormal uterine cavities were retrospectively evaluated by using MR imaging. The diagnosis of an abnormal uterine cavity included a thickened endometrium, and/or a endometrial mass, and/or a submucosal mass. Threshold values to classify the uterine cavity as abnormal on sagittal T2-weighted images were >10 mm for premenopausal women and >5 mm for postmenopausal women. Malignancy was diagnosed when lesions invaded the myometrial/junctional zone, and/or lesion enhancement was lower than that of the adjacent myometrium. The results found that histology confirmed 18 malignant and 37 benign lesions. Twelve of 15 endometrial carcinomas and 3 malignant mixed mesodermal tumors (MMMT) were correctly characterized as malignant on enhanced T1-weighted images; whereas 6 of 15 endometrial carcinomas and 3 MMMT were correctly characterized on T2-weighted images. Thirty-four of 37 benign cases were correctly characterized as not malignant on enhanced T1-weighted images. One of 14 submucosal leiomyomas, one endometrial stromal metaplasia, and one of ten pathologically normal endometria were misdiagnosed on enhanced T1-weighted images but were correctly diagnosed on T2-weighted images. The overall sensitivity, specificity, and accuracy for distinguishing malignant from benign central uterine masses were 83%, 92%, and 89% for enhanced T1-weighted image, and 50%, 97%, and 82% for T2-weighted image, respectively. We came to the conclusion that in diagnosing patients with abnormal uterine cavity, MR imaging may help differentiate malignant from benign disorders. 相似文献
354.
《中国化学快报》2020,31(12):3178-3182
Hepatocellular carcinoma (HCC) has become the fourth predominant cause of cancer-related deaths worldwide, and HCC is still one of the worst prognoses for survival as it is poorly responsive to both chemotherapy and surgical treatment due to drug resistance and great toxic effects. Triptolide (TP), a key ingredient from the traditional Chinese medical herb, has been utilized to treat inflammation and antitumor for centuries. However, investigations of this potent agent have been met with only limited success due to the severe systemic toxicities in patients and low water solubility as well as its high toxicity over the past two decades. Herein, we reported the development of a reduction-responsive drug delivery system loaded with TP for glutathione (GSH)-triggered drug release for cancer therapy. With the GSH-sensitive TP loaded nanoparticles, the remarkable increases in tumor accumulation and amelioration of drug toxicity in animals are demonstrated, which is likely due to sustained stepwise release of active TP within cancer cells. Moreover, in a patient-derived tumor xenograft model of liver cancer, administration of tritolide nanoparticles enhances the antitumor efficacy relative to administration of free TP. These findings indicate that GSH-sensitive release of TP may be a promising strategy for cancer treatment. 相似文献
355.
Rui Liu Hui Zou Zhen-Xing Zou Fei Cheng Xia Yu Ping-Sheng Xu 《Natural product research》2020,34(19):2709-2714
AbstractTwo new anthraquinone derivatives, selaginones A (1) and B (2), and one new triarylbenzophenone analog, selagibenzophenone B (3), were isolated from Selaginella tamariscina (Beauv.) Spring. Their structures were established by 1D-, 2D-NMR and HR-ESI-MS data. Compounds 1 and 2 represent the uncommon examples of aryl substituted anthraquinone derivatives. Especially, compound 2 is a unique anthranone with exceptional structural feature, in which a p-hydroxyphenyl moiety is attached to the C-10 position. Compound 3 is the second naturally occurring triarylbenzophenone and showed moderate activity against SMCC-7721 and MHCC97-H cell lines with IC50 values of 39.8, 51.5 μM respectively. 相似文献
356.
《Arabian Journal of Chemistry》2020,13(7):5978-5995
A new series of cyanoacrylamides incorporating sulphamethoxazol were prepared and confirmed by different spectral tools. Anticancer screening of the new compounds was done against three different types of carcinoma cell lines involving (A549, HCT116, and MDA) using MTT assay. Compound 7 among all tested derivatives achieved the best cytotoxic effect against all tested carcinoma cell lines. HCT116 revealed the best sensitivity and cytotoxic activity toward compound 7 relative to 5-FU. The target compound offered less toxic effect when tested on normal melanocytes (HFB4). Simulation modeling studies revealed strong binding affinity toward the following domains (1dls, 2c6o, and 2wgj) and moderate binding modes toward (3eyl, 4kmp, 2w3l, and 5lab) domains with different binding energy scores. Gene expression profile outlined that caspase-3, BAX, and P53 genes were strongly upregulated relative to their control, while BCL2, MMP1, and CDK2 were effectively down regulated assuming the activation of the apoptotic pathway. Flow cytometry technique revealed that compound 7 stimulated cell cycle arrests at the G2/M phase. Other extensive molecular diagnostic tools were utilized in this report as ELISA, DPA, SEM, and TEM assays which confirmed that our target novel compound 7 was a very promising and interesting chemotherapeutic agent with less toxic effect. Also, authors herein suggested that additional sulphamethoxazole linked to 3-(1-phenyl-3-(thiophen-2-yl)-1H-pyrazol-4-yl)acrylonitrile in compound 7 was responsible for its promising cytotoxic activity against colorectal carcinoma cell line. 相似文献
358.
YunBin Chen Xiangyi Liu Dechun Zheng Luying Xu Liang Hong Yun Xu Jianji Pan 《Magnetic resonance imaging》2014
Purpose
To prospectively evaluate the feasibility of diffusion-weighted magnetic resonance imaging (DWI) for monitoring early treatment response to chemoradiotherapy (CRT) of nasopharyngeal carcinoma (NPC).Materials and methods
Thirty-one patients with stage III and IV NPC were enrolled in this study from February 2012 to November 2012.T2-weighted and DWI sequences with diffusion factor of 0 and 800mm²/s were performed using a 3.0 T Philips Achieva TX scanner at baseline and 3 days, 20 days (after the first cycle of chemotherapy), 50 days (6 days after radiotherapy initiation) after neoadjuvant chemotherapy (NAC) initiation. The diameter of each primary lesion and target metastatic lymph node before and after the first cycle of NAC was measured and classified into stable disease (SD), partial response (PR) or completed response (CR) based on RECIST 1.1. The apparent diffusion coefficient (ADC) values and changes compared to baseline at each time point were compared between responders (CR and PR) and non-responders (SD). The rates of residual at the end of CRT were compared between these two groups.Results
A significant increase in ADC was observed at each stage of therapy (P=.001) in lesions of primary and metastatic. The ADC values (ADC), ADC changes (ΔADC) and percentage ADC changes (Δ%ADC) of day 20 in responders were significantly higher than in non-responders for both primary lesions (p=.005, p=.006, p=.008, respectively) and metastatic lymph nodes (p=.002, p=.002, p=.003). Non-responders showed a higher rate of residual for both primary lesions (p=.008) and metastatic lymph nodes (p=.024) than responders.Conclusions
DW MR imaging allows for detecting early treatment response of NPC. Patients with high ADC values and large ADC increase early after NAC initiation tended to respond better to CRT. Thus, accessing the curative effect of NAC in advanced NPC provides the opportunity to adjust following CRT regimen. 相似文献359.
Yang Shin Park Chang Hee Lee Ji Hoon Kim In Seong Kim Berthold Kiefer Tae Seok Seo Kyeong Ah Kim Cheol Min Park 《Magnetic resonance imaging》2014
Purpose
To assess the usefulness of intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) for predicting lipiodol uptake in patients with hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE).Materials and methods
The institutional review board approved this study. 44 HCC patients underwent IVIM-DWI and Gd-EOB-DTPA-enhanced MRI prior to TACE. Using post-TACE CT as a reference standard, each HCC was classified into either lipiodol good uptake (LGU) or poor uptake (LPU) group. Apparent diffusion coefficient (ADC), true diffusion coefficient (D), perfusion coefficient (D*), and perfusion fraction (f) in HCC were calculated. Arterial enhancement ratio (AER) and IVIM parameters were compared between those two groups using the Mann-Whitney U test.Results
Of the 51 HCCs, 37 (72.5%) were LGU group and 14 (27.5%) were LPU group. AER of HCC was significantly higher in LGU than LPU (0.99 ± 0.54 and 0.67 ± 0.45; P = .034). ADC, D, and f values were not significantly different (P = .073, .059, and .196, respectively) between these two groups. D* was significantly elevated in LGU than LPU (48.10 ± 15.33 and 26.75 ± 9.55; P = .001).Conclusion
Both AER derived from contrast enhanced MRI and D* values derived from IVIM-DWI for HCC were significantly higher in LGU than in LPU. These parameters would be helpful for predicting the lipiodol uptake. 相似文献360.
Doxorubicin‐Anchored Curcumin Nanoparticles for Multimode Cancer Treatment against Human Liver Carcinoma Cells 下载免费PDF全文
Venkatesan Rajiu Perumalsamy Balaji Thankaraj Salammal Sheena Mohammad Abdulkader Akbarsha Kulandaivel Jeganathan 《Particle & Particle Systems Characterization》2015,32(11):1028-1042
Curcumin (Curcuma longa L), a yellow‐colored Indian spice, receives immense attention for the prevention and treatment of various cancers. Despite the superlative therapeutic efficacy, its poor solubility and instability in the aqueous medium hinder the effectiveness of cancer treatment. The novel preparation of curcumin nanoparticles by mechanical grinding of curcumin crystals without any toxic organic solvents is described here for the first time. The surface of curcumin nanoparticles is modified with the negatively charged polyelectrolyte poly(sodium 4‐strynesulfonate) through hydrogen bonding, which is the key to increasing the solubility and stability in the aqueous medium. The negative surface charge is exploited to conjugate doxorubicin drug molecule on the surface of curcumin nanoparticles as evidenced by fluorescence quenching experiments. Doxorubicin‐conjugated curcumin nanoparticles have a higher solubility with an enhanced cytotoxic effect toward the human hepatocellular carcinoma cell line by a reactive‐oxygen‐species‐mediated p53‐dependent apoptotic pathway. The combination of chemotherapy and photodynamic therapy significantly enhances antitumor activity of doxorubicin‐conjugated curcumin nanoparticles, and is expected to be a promising anticancer agent with special reference to human liver carcinoma cells. 相似文献