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61.
62.
Role of Resveratrol as Radiosensitizer by Targeting Cancer Stem Cells in Radioresistant Prostate Cancer Cells (PC-3) 下载免费PDF全文
Sanaa A El-BenhawyMohmed I MorsiEnayat I FahmyMoustafa A SoulaFatma Al Zahraa FH KhalilAmal Refaat Arab 《Asian Pacific journal of cancer prevention》2021,22(12):3823-3837
Aim of Work: Here, we examined the role of resveratrol as a radiosensitizer by targeting cancer stem cells in radioresistant prostate cancer cells (PC-3) using stem cell markers CD44, CD49b and CD29, SOX2, OCT4, CXCR4, DCLK1 and EMT markers such as VIM and E-cadherin. Material and Methods: This study was an in vitro study involving PC-3 cell line which was dividing into four groups. Group I (CO): Control group composed of cells grown in the same medium without treatment with ionizing radiation or resveratrol. Group II (IR): Cells were treated with ionizing radiation alone. Group III (RV): Cells were treated with resveratrol alone. Group VI (IR&RV): The cells were treated with ionizing radiation and resveratrol in combination. The viability of cells was assessed by MTT assay. Genes of interest were measured by RT-PCR and the radiosensitizing efficacy of RV on proliferating cancer cells was determined by clonogenic assay. Results: Ionizing radiation significantly reduced PC-3 viability, lowered stem cell markers and affected epithelial to mesenchymal transition (EMT) genes expression at all doses (2, 4, 6 and 8 Gray). Resveratrol significantly decreased PC-3 viability and lowered stem cell markers and EMT genes expression at concentrations 35, 70 and 140 µM. Combining resveratrol treatment with ionizing radiation leads to significant reduction in cell viability and stem cell markers genes which was noticed with increasing the radiation dose when compared to ionizing radiation alone treated group. Conclusion: Resveratrol has a radiosensitizing effect, that ability is triggered by reducing the expression of cancer stem cell markers and affecting EMT markers. Resveratrol showed to be a good candidate for further studies as anticancer drug in the treatment of human prostate cancer. 相似文献
63.
Establishment of a platform for molecular and immunological characterization of the RNA‐dependent‐RNA‐polymerase NS5B of an Egyptian HCV isolate 下载免费PDF全文
64.
Samantha Jane Wala Jason Raj Karamchandani Rola Saleeb Andrew Evans Qiang Ding Rania Ibrahim Michael Jewett Maria Pasic Antonio Finelli Kenneth Pace Evi Lianidou George Makram Yousef 《Molecular oncology》2015,9(8):1667-1677
Papillary renal cell carcinoma (pRCC) is the second most common RCC subtype and can be further classified as type 1 (pRCC1) or 2 (pRCC2). There is currently minimal understanding of pRCC1 pathogenesis, and treatment decisions are mostly empirical. The aim of this study was to identify biological pathways that are involved in pRCC1 pathogenesis using an integrated genomic approach. By microarray analysis, we identified a number of significantly dysregulated genes and microRNAs (miRNAs) that were unique to pRCC1. Integrated bioinformatics analyses showed enrichment of the focal adhesion and extracellular matrix (ECM) pathways. We experimentally validated that many members of these pathways are dysregulated in pRCC1. We identified and experimentally validated the downregulation of miR‐199a‐3p in pRCC1. Using cell line models, we showed that miR‐199a‐3p plays an important role in pRCC1 pathogenesis. Gain of function experiments showed that miR‐199a‐3p overexpression significantly decreased cell proliferation (p = 0.013). We also provide evidence that miR‐199a‐3p regulates the expression of genes linked to the focal adhesion and ECM pathways, such as caveolin 2 (CAV2), integrin beta 8 (ITGB8), MET proto‐oncogene and mammalian target of rapamycin (MTOR). Using a luciferase reporter assay, we further provide evidence that miR‐199a‐3p overexpression decreases the expression of MET and MTOR. Using an integrated gene/miRNA approach, we provide evidence linking miRNAs to the focal adhesion and ECM pathways in pRCC1 pathogenesis. This novel information can contribute to the development of effective targeted therapies for pRCC1, for which there is none currently available in the clinic. 相似文献
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66.
Adenylate cyclase and guanylate cyclase activity in normal and leukemic human lymphocytes 总被引:1,自引:0,他引:1
Adenylate cyclase (AC) and guanylate cyclase (GC) activities were studied in normal B-enriched and T-enriched lymphocytes, in lymphocytes of children with acute lymphocytic leukemia (ALL), and in lymphocytes of adults with chronic lymphocytic leukemia (CLL). AC activity was greater in normal B than T lymphocytes (215 pmole/min/mg protein versus 80 pmole in the membrane-enriched fraction) and i both increased greatly after stimulation with isoproterenol and more so with prostaglandins E and F2 alpha. In leukemic lymphocytes, AC showed depressed activity (20 pmole in ALL cells and 55 pmole in CLL cells) and was less sensitive to hormonal stimulation: this loss of sensitivity occurred to a greater extent in ALL than in CLL lymphocytes. GC activity was greater in normal T than B cells (in membrane-enriched fraction: 10.2 pmole versus 5.3 pmole). It increased little with isoproterenol and prostaglandins stimulation, and much more with sodium azide and dehydroascorbic acid stimulation. GC activity was increased in both types of leukemic lymphocytes (23 pmole for ALL cells and 18 pmole for CLL cells) and was insensitive to stimulation. Possible derangement of cyclase and cyclic nucleotide regulation in leukemic cells is suggested. 相似文献
67.
Arslanian SA Lewy V Danadian K Saad R 《The Journal of clinical endocrinology and metabolism》2002,87(4):1555-1559
Functional adrenal hyperandrogenism occurs in women with polycystic ovary syndrome (PCOS). Insulin, similar to its ovarian effect, may impact the regulation of adrenal steroidogenesis by modulating the activity of P450c17alpha, the rate-limiting enzyme in androgen biosynthesis. We previously demonstrated that obese adolescents with PCOS are severely insulin resistant and are at heightened risk for impaired glucose tolerance and type 2 diabetes. In the present study we tested the hypothesis that metformin therapy in obese adolescents with PCOS will attenuate the adrenal steroidogenic response to ACTH, with reduction of insulin resistance/insulinemia. Fifteen adolescents with PCOS and impaired glucose tolerance received 3 months of metformin (850 mg, twice daily) therapy. Pre- and posttherapy they had oral glucose tolerance testing, ACTH stimulation test, a 3-h hyperinsulinemic (80 mU/m(2).min)-euglycemic clamp to assess insulin sensitivity and a hyperglycemic clamp to assess insulin secretion. After 3 months of metformin treatment, glucose intolerance improved, with eight subjects having normal glucose tolerance. Total and free T decreased [1.5 +/- 0.2 vs. 1.0 +/- 0.1 nmol/liter (P = 0.022) and 41.3 +/- 8.3 vs. 22.2 +/- 2.1 pmol/liter (P = 0.028), respectively]. Insulin-stimulated glucose disposal increased (21.5 +/- 2.2 vs. 25.0 +/- 2.2 micromol/kg.min; P = 0.041). Fasting insulin and oral glucose tolerance test insulin and glucose area under the curve decreased significantly. ACTH-stimulated increases in androstenedione, 17-hydroxyprogesterone, and 17-hydroxypregnenelone were lower after metformin treatment [2.8 +/- 0.4 vs. 1.7 +/- 0.3 nmol/liter (P = 0.014), 7.0 +/- 0.6 vs. 5.3 +/- 0.5 nmol/liter (P = 0.011), and 30.4 +/- 3.7 vs. 25.7 +/- 4.2 nmol/liter (P = 0.054)]. Fasting insulin correlated with the 17-hydroxypregnenelone response to ACTH stimulation (r = 0.52; P = 0.008). In summary, metformin treatment of obese adolescents with PCOS and impaired glucose tolerance is beneficial in improving glucose tolerance and insulin sensitivity, in lowering insulinemia, and in reducing elevated androgen levels. Moreover, metformin therapy is associated with attenuation of the adrenal steroidogenic response to ACTH. Metformin therapy was well tolerated. In conclusion, double blind, placebo-controlled studies will determine whether insulin-sensitizing therapy corrects not only ovarian hyperandrogenism but also functional adrenal hyperandrogenism in adolescents with PCOS. 相似文献
68.
Background
Pain and/or functional disorders, such as weakness or movement control disorders, often have a myofascial origin. The pathophysiological substrates of myofascial problems are myofascial trigger points (mTrP) and reactive connective tissue alterations. Typical for myofascial pain is that the site of the origin of pain and the site of pain perception often do not lie in the same place (referred pain). Myofascial disorders can have a primary or a secondary cause and often make a substantial contribution to stimulus summation problems. In the process of clinical reasoning it needs to be investigated what value mTrP and fascial alterations have for the current problem in question (e.g. primary, secondary and contribution to stimulus summation).Methods
The causal and sustained therapy of myofascial disorders considers the contractile part of muscle (contracture knots) as well as the noncontractile parts (reactive connective tissue alterations). Predisposition and maintaining factors have to be recognized and if possible included in the therapy, depending on the necessity. The trigger point therapy IMTT® (“Interessengemeinschaft für Myofasziale Triggerpunkt-Therapie”) encompasses manual techniques and if necessary dry needling for deactivation of the disruption potential of mTrP, stretching/detonization and functional training/ergonomics. 相似文献69.
70.
刺南蛇藤倍半萜的研究 总被引:1,自引:0,他引:1
从刺南蛇藤(Celastrus flagelaris Rupr.)种子油中分离到八个β-二氢沉香呋喃倍半萜,经红外、紫外、质谱及核磁共振谱确定它们的结构是1α-乙酰氧基-2α,9β-二肉桂酰氧基-β-二氢沉香呋喃(1),1α,6β,13-三乙酰氧基-9β-苯甲酰氧基-β-二氢沉香呋喃-(2),triptogelinG-1(3),1α,6β-二乙酰氧基-9β-苯甲酰氧基-β-二氢沉香呋喃(4),triptogelinF-2(5),1α,2α-二乙酰氧基-9β-肉桂酰氧基-β-二氢沉香呋喃(6),celaforlinB-3(7),1α,6β-二乙酰氧基-8α-肉桂酰氧基-9α-苯酰氧基-β-二氢沉香呋喃(8)。其中1是新化合物,命名为celastrine B。 相似文献