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1.
《Molecular therapy》2022,30(3):1171-1187
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Objective: Hepatocellular carcinoma (HCC) microenvironment has been recognized as a key contributor for cancer progression, metastasis, and drug resistance. The crosstalk between tumor cells, the vascular endothelial growth factor (VEGF), and the chemokine (C-C motif) ligand 2 (CCL2) signaling networks mediates immunoinhibitory impact and facilitates tumor angiogenesis. The current investigation aimed at exploring the potent anti-cancer activity of the newly designed nano-based anti-cancer therapy comprising anti-VEGF drug, avastin (AV), and CCR2 antagonist (CR) to counteract HCC and tracking its mode of action in vivo. Methods: The prepared AV, CR, and AVCR nanoprototypes were characterized by nanoscale characterization techniques in our previous work. Here, they are applied for unearthing their anti-cancer properties / mechanisms in hepatic cancer-induced rats via analyzing protein levels and genetic expression of the elements incorporated in the angiogenesis, apoptosis, and metastasis signalling pathways. Results: The present results revealed a significant down-regulation in the angiogenesis, survival and metastasis indices along with up-regulation in the pro-apoptotic mediators upon treatment of hepatic cancer-bearing rats with the novel synthesized nanomaterials when compared with the untreated counterparts. We showed across HCC model that anti-VEGF in combination with CCR2 antagonism therapy leads to sensitization and enhanced tumor response over anti-VEGF or CCR2 antagonism monotherapy, particularly in its nanoscale formulation. Conclusion: The present approach provides new mechanistic insights into the powerful anti-hepatic cancer advantage of the novel nanoprototypes which is correlated with modulating critical signal transduction pathways implicated in tumor microenviroment such as angiogenesis, apoptosis and metastasis. This research work presents a substantial foundation for future studies focused on prohibiting cancer progression and recovery by targeting tumor microenviroment.  相似文献   
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Introduction: Lichen planus (LP) is a relatively common chronic mucocutaneous disease that affects the skin and mucous membranes, including oral mucosa. The etiology of the disease is unknown. Some evidence suggests that the immune system and inflammation may play a role in the formation and progression of lichen planus. Some authorities believe that LP is a precancerous condition. The purpose of this study was to investigate the serum levels of the inflammatory cytokines CRP, IL-1, IL-6, and TNF- in patients with oral lichen planus and oral squamous cell carcinoma (OSCC), as well as to assess the relationship between these cytokine levels and clinical symptoms. Methods: A total of 75 subjects, with 25 in each group of oral lichen planus, healthy control, and oral squamous cell carcinoma, participated in this cross-sectional study. Serum levels of IL-1α, TNF-α, IL-6, and CRP were determined and compared. In comparison to the healthy control group, the lichen planus and oral squamous cell carcinoma groups had higher levels of CRP, IL-1α, IL-6, and TNF-α. Results: We discovered that the mean mRNA and protein levels of CRP, IL-1α, IL-6, and TNF-α were significantly higher in the blood and tissue of lichen planus and OSCC patients than in normal controls. Conclusion: Higher levels of CRP, IL-1α, IL-6, and TNF-α may be linked to OLP and oral carcinogenesis. More research with larger groups is required.  相似文献   
4.
Adiponectin is the major adipocytes-secreted protein involved in obesity-related breast cancer growth and progression. We proved that adiponectin promotes proliferation in ERα-positive breast cancer cells, through ERα transactivation and the recruitment of LKB1 as ERα-coactivator. Here, we showed that adiponectin-mediated ERα transactivation enhances E-cadherin expression. Thus, we investigated the molecular mechanism through which ERα/LKB1 complex may modulate the expression of E-cadherin, influencing tumor growth, progression and distant metastasis. We demonstrated that adiponectin increases E-cadherin expression in ERα-positive 2D and higher extent in 3D cultures. This occurs through a direct activation of E-cadherin gene promoter by ERα/LKB1-complex. The impact of E-cadherin on ERα-positive breast cancer cell proliferation comes from the evidence that in the presence of E-cadherin siRNA the proliferative effects of adiponectin is no longer noticeable. Since E-cadherin connects cell polarity and growth, we investigated if the adiponectin-enhanced E-cadherin expression could influence the localization of proteins cooperating in cell polarity, such as LKB1 and Cdc42. Surprisingly, immunofluorescence showed that, in adiponectin-treated MCF-7 cells, LKB1 and Cdc42 mostly colocalize in the nucleus, impairing their cytosolic cooperation in maintaining cell polarity. The orthotopic implantation of MCF-7 cells revealed an enhanced E-cadherin-mediated breast cancer growth induced by adiponectin. Moreover, tail vein injection of MCF-7 cells showed a higher metastatic burden in the lungs of mice receiving adiponectin-treated cells compared to control. From these findings it emerges that adiponectin treatment enhances E-cadherin expression, alters cell polarity and stimulates ERα-positive breast cancer cell growth in vitro and in vivo, sustaining higher distant metastatic burden.  相似文献   
5.
目的: 借助多种癌症生物信息数据库研究乳腺癌组织中缺氧诱导因子1亚基α (HIF1A)的表达水平及其与乳腺癌患者预后及肿瘤免疫细胞浸润的关系。 方法: 利用Oncomine、人类蛋白质图谱、基因表达谱交互式分析(GEPIA)及TCGA数据库分析HIF1A基因在乳腺癌组织中的表达及其与患者预后、临床病理特征的关系,并在中国人乳腺癌组织标本(选用2011年1月至2015年12月中国武汉大学人民医院手术切除的93例乳腺癌组织和14例良性乳腺疾病组织)中进行验证。对HIF1A高低表达组间的差异基因进行基因本体(GO)和京都基因与基因组百科全书(KEGG)富集分析,用Cibersort R软件评估HIF1A高低表达样本中免疫细胞浸润丰度差异。 结果: 生物信息数据显示,HIF1A在乳腺癌组织中高表达,预示着患者DFS预后更好(P<0.05)。HIF1A的表达与雌激素受体(ERP)、孕激素受体(PR)和人表皮生长因子受体2 (HER2)表达相关(均P<0.05)。GO生物功能及KEGG通路富集分析结果提示,HIF1A可能参与肿瘤免疫调节等生物活动。使用Cibersort分析结果显示,HIF1A与肿瘤免疫细胞浸润之间具有相关性(均P<0.01),发现活化记忆CD4 + T细胞、M0和M1型巨噬细胞与HIF1A表达呈正相关,在乳腺癌组织中高表达,Treg细胞、活化NK细胞、M2型巨噬细胞与HIF1A表达呈负相关(均P<0.01)。 结论: HIF1A参与调节肿瘤微环境的免疫活性,与乳腺癌患者DFS相关,其可能成为乳腺癌分级诊断、免疫治疗和预后判断的生物标志物。  相似文献   
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Bladder cancer is common and one of the most costly cancer forms, due to a lack of curative therapies. Recently, clinical safety and efficacy of the alpha1-oleate complex was demonstrated in a placebo-controlled study of nonmuscle invasive bladder cancer. Our study investigated if long-term therapeutic efficacy is improved by repeated treatment cycles and by combining alpha1-oleate with low-dose chemotherapy. Rapidly growing bladder tumors were treated by intravesical instillation of alpha1-oleate, Epirubicin or Mitomycin C alone or in combination. One treatment cycle arrested tumor growth, with a protective effect lasting at least 4 weeks in mice receiving 8.5 mM of alpha1-oleate alone or 1.7 mM of alpha-oleate combined with Epirubicin or Mitomycin C. Repeated treatment cycles extended protection, defined by a lack of bladder pathology and a virtual absence of bladder cancer-specific gene expression. Synergy with Epirubicin was detected at the lower alpha1-oleate concentration and in vitro, alpha1-oleate was shown to enhance the uptake and nuclear translocation of Epirubicin, by tumor cells. Effects at the chromatin level affecting cell proliferation were further suggested by reduced BrdU incorporation. In addition, alpha1-oleate triggered DNA fragmentation, defined by the TUNEL assay. The results suggest that bladder cancer development may be prevented long-term in the murine model, by alpha1-oleate alone or in combination with low-dose Epirubicin. In addition, the combination of alpha1-oleate and Epirubicin reduced the size of established tumors. Exploring these potent preventive and therapeutic effects will be of immediate interest in patients with bladder cancer.  相似文献   
9.
《Immunobiology》2022,227(6):152298
PLPPs (Phospholipid phosphatases) are widely expressed in different human tissues, regulate cell signal transduction, and are overexpressed in cancers such as gliomas, pancreatic adenocarcinoma, lung adenocarcinoma, and so on. As a member of the PLPP family, PLPP2 (phospholipid phosphatase 2) plays a vital role in the occurrence and development of breast cancer, but its mechanism is still unclear. Our research found that PLPP2 was overexpressed in breast cancer, and the higher expression level of PLPP2 showed a worse prognosis for breast cancer patients. Further analysis showed that overexpression of PLPP2 affected the expression of CDC34 (cell-division cycle 34), LSM7 (Like-Smith 7), and SGTA (small glutamine-rich tetratricopeptide repeat-containing protein alpha) through EMT (epigenetic-mesenchymal transition) related pathways to promote the occurrence and development of breast cancer. In vitro, silencing PLPP2 significantly reduced the proliferation, invasion, and migration abilities of human breast cancer cells MDA-MB-231. ER+ is a common subtype of breast cancer. Furthermore, we found that the overexpression of PLPP2 was significantly related to the poor prognosis of ER+ breast cancer. These results indicate that PLPP2 has value as a potential therapeutic target for breast cancer, especially for ER+ breast cancer.  相似文献   
10.
背景与目的:不育α基序结构域和组氨酸/天冬氨酸残基双联体结构域包涵蛋白1(sterile alpha motif and histidine/aspartic acid domain-containing protein 1,SAMHD1)具有抑制多种肿瘤细胞生长的作用,但其调节肝细胞癌(hepatocellular carcinoma,HCC)细胞增殖的作用及机制尚未见报道。探究SAMHD1调控p27的表达对HCC细胞Huh7的增殖、凋亡和细胞周期的影响。方法:首先通过蛋白质印迹法(Western blot)检测正常肝细胞和不同类型HCC细胞中SAMHD1的表达情况。利用基因修饰技术构建过表达SAMHD1、dNTP酶活性位点突变体(SAMHD1-D207N)和磷酸化位点突变体(SAMHD1-T592E)的重组质粒,然后利用四甲基偶氮唑蓝(methyl thiazolyl tetrazolium,MTT)法检测过表达SAMHD1及其突变体或siRNA干扰沉默SAMHD1对HCC细胞增殖的影响,采用流式细胞术检测细胞周期与细胞凋亡情况。在癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中分析SAMHD1和p27表达的相关性。结果:HCC细胞中SAMHD1表达上调,过表达SAMHD1、SAMHD1-D207N和SAMHD1-T592E可以抑制Huh7细胞增殖,细胞周期停滞在G 1 /G 0 期;相反,干扰SAMHD1后细胞增殖加快,细胞周期停滞在G 2 /M期。机制研究表明,SAMHD1上调细胞周期蛋白激酶抑制因子p27的表达。在HCC组织中,p27的表达与SAMHD1表达呈正相关。结论:过表达SAMHD1可以上调p27的表达,导致细胞周期停滞在G 1 /G 0 期,从而抑制HCC细胞增殖,这种抑制作用不依赖于其dNTP酶活性和磷酸化修饰。  相似文献   
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