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991.
992.
目的研究胎盘特异性基因1(PLAC1)特异性T细胞受体(TCR)基因修饰T细胞对乳腺癌的抗肿瘤作用。
方法磁珠分选人类白细胞抗原分型为A2(HLA-A2)的志愿者外周血单个核细胞(PBMC)中的CD8+ T细胞,流式检测CD8+ T细胞的表型。通过慢病毒载体构建、包装,将可识别乳腺癌肿瘤抗原PLAC1的HLA-A2限制性的TCR基因导入CD8+ T细胞(称为TCR-T细胞),以慢病毒空载体包装、感染的CD8+ T细胞(NC-T细胞)作为对照细胞,通过流式细胞术检测PLAC1特异性TCR的表达效率。免疫荧光和流式细胞术检测乳腺癌细胞MCF-7和MDA-MB-231(三阴性乳腺癌细胞)的PLAC1和HLA-A2血清型的表达。WST-1法检测不同效靶比(5?:?1、10?:?1和20?:?1)TCR-T细胞或NC-T细胞与乳腺癌细胞MCF-7或MDA-MB-231作用后的细胞毒性,并通过ELISA检测共培养后T细胞IFN-γ的释放量。通过裸鼠皮下人乳腺癌移植瘤模型检测TCR-T细胞以及NC-T细胞的抗肿瘤作用。采用单因素方差分析及独立t检验进行统计学分析。
结果磁珠分选出的CD8+ T细胞CD3+ CD8+比例达到(98.89±0.30)%。经慢病毒感染、五聚体检测,TCR-T细胞中PLAC1特异性TCR的正确表达率为(24.58±0.82)%,NC-T细胞不表达PLAC1特异性TCR。免疫荧光和流式结果显示乳腺癌细胞MCF-7和MDA-MB-231为HLA-A2和PLAC1双阳性表达细胞。其中流式检测结果显示,MCF-7和MDA-MB-231细胞中HLA-A2的表达效率分别为(93.04±1.36)%和(98.72±0.12)%。在效靶比为20?:?1时,TCR-T细胞对MCF-7杀伤率为(51.5±1.37)%,高于NC-T细胞对MCF-7的杀伤率(5.93±2.40)%,t = 15.507,P < 0.01;TCR-T细胞对MDA-MB-231杀伤率为(44.34±2.20)%,高于NC-T细胞对MDA-MB-231杀伤率(5.15±2.40)% (t?= 10.694,P < 0.01)。在相同效靶比情况下,TCR-T细胞对MCF-7或MDA-MB-231细胞的细胞毒性高于NC-T细胞,且随着效靶比的增加杀伤效果增强。在效靶比为20?:?1时,与MCF-7共培养后TCR-T细胞IFN-γ的分泌水平[(347.49±4.10)pg/ml]高于NC-T细胞[(18.14±6.22)pg/ml](t = -76.638,P < 0.01);与MDA-MB-231共培养后TCR-T细胞IFN-γ的分泌水平为(255.25±6.85)pg/ml,高于NC-T细胞[(14.70±6.38)pg/ml] (t = -44.526,P < 0.01),且随着效靶比的增加分泌量升高。在裸鼠皮下人乳腺癌移植瘤实验中,生理盐水组和NC-T细胞移植组小鼠的肿瘤生长迅速,TCR-T细胞治疗组小鼠肿瘤生长相对缓慢,在移植后第35天,生理盐水组、NC-T细胞组和TCR-T细胞组小鼠肿瘤的平均体积分别为(5?636.96±2?879.55)mm3、(5?522.12±3?391.48)mm3和(1?403.85±1?394.31)mm3,TCR-T细胞治疗组小鼠肿瘤体积明显小于生理盐水组(F = 0.1813,P < 0.05)和NC-T细胞组(F = 0.1307,P?< 0.05)。
结论PLAC1特异性TCR基因修饰T细胞对乳腺癌细胞具有较强的抗肿瘤作用,PLAC1可作为乳腺癌治疗的潜在靶标;PLAC1特异性TCR基因修饰T细胞治疗是PLAC1表达阳性的乳腺癌治疗的新策略。 相似文献
993.
994.
《Cryobiology》2017
Evidence is mounting for a relationship between human semen quality and environmental/lifestyle/socioeconomic factors including long term health outcomes such as mortality. The relationship between pre-freeze and post-thaw semen quality in cancer patients and these factors are unknown. Frozen semen from 217 cancer patients was thawed and analysed using a validated CASA method. Post-thaw quality was matched and compared with WHO semen analysis performed prior to storage. The English Indices of Deprivation 2010 were matched with patients and then examined for relationships with pre-freeze and post-thaw semen quality. There is a relationship between semen quality and deprivation in cancer patients. Compared with pre-freeze semen quality, post-thaw semen quality has a stronger relationship with deprivation. Sperm cryopreservation may have potential as a systemic health diagnostic test and is predictive of cancer patient mortality. 相似文献
995.
996.
Gangning Liang 《Epigenetics》2017,12(6):416-432
DNA methylation aberrancies are hallmarks of human cancers and are characterized by global DNA hypomethylation of repetitive elements and non-CpG rich regions concomitant with locus-specific DNA hypermethylation. DNA methylation changes may result in altered gene expression profiles, most notably the silencing of tumor suppressors, microRNAs, endogenous retorviruses and tumor antigens due to promoter DNA hypermethylation, as well as oncogene upregulation due to gene-body DNA hypermethylation. Here, we review DNA methylation aberrancies in human cancers, their use in cancer surveillance and the interplay between DNA methylation and histone modifications in gene regulation. We also summarize DNA methylation inhibitors and their therapeutic effects in cancer treatment. In this context, we describe the integration of DNA methylation inhibitors with conventional chemotherapies, DNA repair inhibitors and immune-based therapies, to bring the epigenome closer to its normal state and increase sensitivity to other therapeutic agents to improve patient outcome and survival. 相似文献
997.
Ankita Deb Bhavana Deshmukh Pranay Ramteke Firoz Khan Bhati Manoj Kumar Bhat 《Translational oncology》2021,14(10)
Resistin, a small secretory molecule, has been implicated to play an important role in the development of insulin resistance under obese condition. For the past few decades, it has been linked to various cellular and metabolic functions. It has been associated with diseases like metabolic disorders, cardiovascular diseases and cancers. Numerous clinical studies have indicated an increased serum resistin level in pathological disorders which have been reported to increase mortality rate in comparison to low resistin expressing subjects. Various molecular studies suggest resistin plays a pivotal role in proliferation, metastasis, angiogenesis, inflammation as well as in regulating metabolism in cancer cells. Therefore, understanding the role of resistin and elucidating its’ associated molecular mechanism will give a better insight into the management of these disorders. In this article, we summarize the diverse roles of resistin in pathological disorders based on the available literature, clinicopathological data, and a compiled study from various databases. The article mainly provides comprehensive information of its role as a target in different treatment modalities in pre as well as post-clinical studies. 相似文献
998.
Eun-Ji Ko Kyoung Seob Song Mee Sun Ock Yung Hyun Choi Suhkmann Kim Heui-Soo Kim Hee-Jae Cha 《BMB reports》2021,54(7):368
The vertebrate genome contains an endogenous retrovirus that has been inherited from the past millions of years. Although approximately 8% of human chromosomal DNA consists of sequences derived from human endogenous retrovirus (HERV) fragments, most of the HERVs are currently inactive and non-infectious due to recombination, deletions, and mutations after insertion into the host genome. Several studies suggested that Human endogenous retroviruses (HERVs) factors are significantly related to certain cancers. However, only limited studies have been conducted to analyze the expression of HERV derived elements at protein levels in certain cancers. Herein, we analyzed the expression profiles of HERV-K envelope (Env) and HERV-R Env proteins in eleven different kinds of cancer tissues. Furthermore, the expression patterns of both protein and correlation with various clinical data in each tissue were analyzed. The expressions of both HERV-K Env and HERV-R Env protein were identified to be significantly high in most of the tumors compared with normal surrounding tissues. Correlations between HERV Env expressions and clinical investigations varied depending on the HERV types and cancers. Overall expression patterns of HERV-K Env and HERV-R Env proteins were different in every individual but a similar pattern of expressions was observed in the same individual. These results demonstrate the expression profiles of HERV-K and HERV-R Env proteins in various cancer tissues and provide a good reference for the association of endogenous retroviral Env proteins in the progression of various cancers. Furthermore, the results elucidate the relationship between HERV-Env expression and the clinical significance of certain cancers. 相似文献
999.
Penelope M. Drake Birgit Schilling Richard K. Niles Miles Braten Eric Johansen Haichuan Liu Michael Lerch Dylan J. Sorensen Bensheng Li Simon Allen Steven C. Hall H. Ewa Witkowska Fred E. Regnier Bradford W. Gibson Susan J. Fisher 《Analytical biochemistry》2011,(1):71
Glycans are cell-type-specific, posttranslational protein modifications that are modulated during developmental and disease processes. As such, glycoproteins are attractive biomarker candidates. Here, we describe a mass spectrometry-based workflow that incorporates lectin affinity chromatography to enrich for proteins that carry specific glycan structures. As increases in sialylation and fucosylation are prominent among cancer-associated modifications, we focused on Sambucus nigra agglutinin (SNA) and Aleuria aurantia lectin (AAL), lectins which bind sialic acid- and fucose-containing structures, respectively. Fucosylated and sialylated glycopeptides from human lactoferrin served as positive controls, and high-mannose structures from yeast invertase served as negative controls. The standards were spiked into Multiple Affinity Removal System (MARS) 14-depleted, trypsin-digested human plasma from healthy donors. Samples were loaded onto lectin columns, separated by HPLC into flow-through and bound fractions, and treated with peptide: N-glycosidase F to remove N-linked glycans. The deglycosylated peptide fractions were interrogated by ESI HPLC-MS/MS. We identified a total of 122 human plasma glycoproteins containing 247 unique glycosites. Importantly, several of the observed glycoproteins (e.g., cadherin 5 and neutrophil gelatinase-associated lipocalin) typically circulate in plasma at low nanogram per milliliter levels. Together, these results provide mass spectrometry-based evidence of the utility of incorporating lectin-separation platforms into cancer biomarker discovery pipelines. 相似文献
1000.
Results from recent studies support the hypothesis that cancer stem cells (CSCs) are responsible for tumor initiation and formation. Here, we applied a proteome profiling approach to investigate the mechanisms of CSCs and to identify potential biomarkers in the prostate cancer cell line DU145. Using MACS, the DU145 prostate cancer cell line was isolated into CD44+ or CD44− cells. In sphere culture, CD44+ cells possessed stem cell characteristics and highly expressed genes known to be important in stem cell maintenance. In addition, they showed strong tumorigenic potential in the clonogenic assay and soft agar colony formation assay. We then analyzed and identified proteins that were differentially expressed between CD44+ and CD44− using two-dimensional gel electrophoresis and LC-MS/MS. Cofilin and Annexin A5, which are associated with proliferation or metastasis in cancer, were found to be positively correlated with CD44 expression. These results provide information that will be important to the development of new cancer diagnostic tools and understanding the mechanisms of CSCs although a more detailed study is necessary to investigate the roles of Cofilin and Annexin A5 in CSCs. 相似文献