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21.
应用胶银技术,对软组织肿瘤特别是纤维源性肿瘤核仁组成区蛋白进行了定量研究。在软组织一些恶性肿瘤中,以血管肉瘤、横纹肌肉瘤核仁组成区蛋白均值最高,并以此排列了它们的恶性度顺序。在纤维源性肿瘤中,纤维瘤、瘤样纤维组织增生、纤维肉瘤及其亚类核仁组成区蛋白均值有显著与高度显著性差异(P<0.05、P<0.001),其中随访的34例纤维肉瘤患者,具有高核仁组成区蛋白均值(≥5)与低核仁组成区蛋白均值(<5)的5年生存率分别是20%和53%(P<0.05)。因此,作者认为核仁组成区蛋白定量在判定软组织肿瘤的恶性度、鉴别其良恶性及预测患者预后中均有一定实用价值。  相似文献   
22.
Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities.  相似文献   
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《Endocrine practice》2023,29(5):408-413
ObjectiveOsteoporosis is a common condition that can be caused or exacerbated by estrogen deficiency.MethodsThis narrative review will discuss optimizing bone health in the setting of adjuvant endocrine treatments for hormone receptor–positive breast cancer and the current use of antiresorptive agents as adjuvant therapy and as bone modifying agents.ResultsAdjuvant endocrine treatments for hormone receptor–positive breast cancer (tamoxifen and aromatase inhibitors) affect bone health. The exact effect depends on the agent used and the menopausal state of the woman. Antiresorptive medications for osteoporosis, bisphosphonates and denosumab, lower the risk of bone loss from aromatase inhibitors. Use of bisphosphonates as adjuvant treatment in breast cancer, regardless of hormone receptor status, is increasing because of benefits seen to cancer relapse and survival.ConclusionOptimizing bone health in women with breast cancer during and after cancer treatment is informed by an understanding of breast cancer treatment and its skeletal effect.  相似文献   
25.
Oestrogen receptor (ER) status of 77 cases of screen-detected breast cancer has been determined using cytological preparations. In 48% ER status was positive, which was the same proportion as that formed in a control group of age-matched patients with symptomatic breast carcinoma. Since the screen-detected group contained more low grade tumours, the percentage of ER-positive cases would be expected to be higher. the reasons for the discrepancy are discussed. Ki67 score has been determined for 41 cases of screen-detected cancer. Ki67 score showed a positive correlation with histological tumour grade and a negative correlation with ER status. However, there was no correlation with tumour size or lymph node status. the Ki67 scores in the screen-detected cancers were essentially similar to those found in an age-matched symptomatic group, but the very low scores were only found in the screened group.  相似文献   
26.
The malignant potential of solid tumors is related to the ability to invade adjacent tissue and to metastasize. These properties of cancer cells depend on the synthesis of proteolytic enzymes which are able to digest adjacent connective tissue and basement membranes. We hypothesized that all elements of the plasminogen activation system might be overexpressed in malignant human breast tumors, functioning as an essential element in tumor invasion and metastasis. As determined by histopathological methods, the malignant tumors showed statistically significantly higher expression of urokinase plasminogen activator (uPA), type-1 plasminogen activator inhibitor (PAI-1), and especially urokinase plasminogen activator receptor (uPAR) than benign tissues. All those elements were present in higher amounts in the cancer cells than in the cells of benign or normal breast tissues. High exhibition of tissue plasminogen activator (tPA) found in cancer seems to be random and not related to the malignant or benign state, since benign and malignant tumors show overexpression of tissue plasminogen activator with similar frequency. When the tumors express high amounts of uPA, they express a high amount of uPAR in 50% of cases and PAI-1 in 57.3% of cases. When urokinase is expressed in low amount, the receptor is low in 28.6% and inhibitor in 21.4% of malignant breast tumors. This statistically significant consensus, 78.6% in the case of urokinase and its receptor and 78.6% in case of urokinase and its inhibitor, suggests that these activities may be the result of a unique mechanism of control, activated in the last steps of malignant transformation.  相似文献   
27.
分化聚类36(cluster of differentiation 36,CD36)是一种位于细胞表面的膜蛋白受体,可以结合并转运脂肪酸。内质网膜蛋白4B (Nogo-B)在肝脏中调控脂肪酸代谢而影响肝癌的发展。目前并不清楚CD36和Nogo-B的相互作用是否能够影响乳腺癌细胞的增殖和迁移。本研究在三阴性乳腺癌(triple-negative breast cancer,TNBC)细胞中同时干预CD36与Nogo-B的表达来探索它们对细胞增殖与迁移的影响。结果表明在三阴性乳腺癌细胞中,单独抑制CD36或Nogo-B的表达都能够抑制细胞的增殖与迁移;同时抑制CD36与Nogo-B的表达时,这种抑制效果更加明显,且Vimentin、B细胞淋巴瘤-2(B-cell lympoma-2,BCL2)和增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)的表达受到抑制。在小鼠移植瘤模型中,E0771细胞转染CD36或Nogo-B的siRNA后成瘤能力降低;同时敲减CD36和Nogo-B时,肿瘤生长速度显著减慢。机制研究发现,抑制CD36和Nogo-B表达能够抑制脂肪酸结合蛋白4(fatty acid binding protein 4,FABP4)和脂肪酸转运蛋白4(fatty acid transport protein 4,FATP4) mRNA的含量,同时CD36和Nogo-B过表达刺激的细胞增殖被FABP4的siRNA降低,预示着抑制乳腺癌细胞中CD36与Nogo-B的表达可能通过抑制脂肪酸的吸收和转运而抑制细胞的生长和迁移。此外,抑制CD36与Nogo-B的表达可激活P53-P21-Rb信号通路,参与抑制CD36与Nogo-B表达而抑制的细胞增殖与迁移。本研究证明同时抑制CD36和Nogo-B的表达能够协同抑制三阴性乳腺癌细胞的增殖和迁移,为临床抗三阴性乳腺癌药物的开发提供了新的靶点。  相似文献   
28.
摘要 目的:探讨乳腺良恶肿瘤患者超声弹性成像定量参数与临床分期、病理分子分型的相关性。方法:选择2020年1月至2022年12月来我院诊治的乳腺肿块患者85例,均行超声弹性成像检查,分析85例乳腺肿块患者的病理检查结果,对比良恶性肿瘤患者的弹性成像参数,对弹性应变率、直径变化率、面积比及三者联合绘制ROC曲线,分析不同乳腺肿瘤患者临床分期的弹性成像参数,分析乳腺肿瘤患者病理分子分型的弹性成像参数。结果:85例乳腺肿块患者中,良性肿块35例,恶性肿块50例。恶性组的弹性应变率、肿块直径、直径变化率、肿块面积、面积比明显较良性组低(P<0.05)。面积比ROC曲线AUC为0.580,以1.73为临界值,乳腺恶性肿瘤的诊断灵敏度为73.5 %,特异度为38.5 %;直径变化率ROC曲线AUC为0.630,以0.28为临界值,诊断灵敏度为75.5 %,特异度为47.5 %;弹性应变率ROC曲线AUC为0.790,以15.2 cm2为临界值,诊断灵敏度为64.5 %,特异度为83.5 %,以三者联合绘制ROC曲线,AUC为0.920,诊断灵敏度为82.5 %,特异度为92.5 %。乳腺恶性肿瘤患者TNM分期Ⅰ、Ⅱ、Ⅲ、Ⅳ期者的弹性应变率、肿块直径、直径变化率、肿块面积、面积比对比有统计学意义(P<0.05);其中Ⅳ期者的弹性应变率、肿块直径、直径变化率、肿块面积、面积比明显较Ⅲ、Ⅱ、Ⅰ期者高,Ⅲ期者明显较Ⅱ、Ⅰ期者高,Ⅱ期者明显较Ⅰ期高。乳腺恶性肿瘤患者Luminal A型者、Liminal B型者、Her2过表达型者、基底样型者的弹性应变率、肿块直径、直径变化率、肿块面积、面积比对比有统计学意义(P<0.05);其中Liminal B型者的弹性应变率、肿块直径、直径变化率、肿块面积、面积比明显较Luminal A型者、Her2过表达型者、基底样型者高,Her2过表达型者明显较Luminal A型者、基底样型者高(P均<0.05),Luminal A型者与基底样型者对比无统计学意义(P>0.05)。结论:超声弹性成像可用于乳腺良恶肿瘤的诊断,超声弹性成像定量参数可用于恶性乳腺肿瘤临床分期、Liminal B型、Her2过表达型的判断。  相似文献   
29.
为克隆肺腺癌分化相关基因, 采用诱导分化与消减杂交相结合的策略, 建立了全反式维甲酸(RA)诱导前后人肺腺癌细胞系的cDNA消减文库, 得到124个cDNA消减克隆. 经加减法杂交差异筛选、DNA和RNA印迹、cDNA全序列测定和生物学功能分析, 分离到3个在人肺腺癌细胞系分化过程中由RA激活而特异表达的新的cDNA序列这一策略和技术路线适用于分离细胞中呈过量表达或表达抑制基因的cDNA克隆, 并具有反映细胞分化过程中基因表达动态变化特征和相对简便适用的特点.  相似文献   
30.
应用真彩色医学图像分析技术,对51例角结膜缘上皮良、恶性病变(其中上皮增生19例,不典型增生6例,原位癌14例,鳞状细胞癌12例)进行了DNA原位定量分析研究.结果显示:原位癌和鳞状细胞癌DNA含量明显增加,多为高倍异倍体细胞,DNA直方圆明显右移,峰值主要位于>5C处,≥5C细胞分别占78.89%和78.31%;上度增生病变DNA含量较低,多为低倍整倍体细胞,DNA直方图峰值位于2C~4C处,2C~4C细胞占88.59%;上皮不典型增生病变DNA含量介于良性病变和癌之间,DNA直方图逐渐右移,2C~4C细胞占58.62%,≥5C细胞占41.38%。以上数据经统计学处理各组间有显著性差异。表明DNA倍性程度与肿瘤的增殖程度呈正相关,高倍异倍体细胞随肿瘤恶性程度的增高而增多。作者认为DNA原位图像定量分析可为角结膜缘上皮良、恶性病变的诊断、分级及早期发现癌变趋势提供一个可靠的参考指标。  相似文献   
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