MicroRNA-141在上皮性卵巢癌患者组织和血清中的表达及临床意义的探讨

目的：探讨微小RNA-141（miR-141）在卵巢癌患者组织和血清中的表达情况并初步探讨其作为肿瘤标记物早期诊断上皮性卵巢癌的可行性。方法：采用实时荧光定量逆转录聚合酶链反应（real-timeRT—PCR）检测16例上皮性卵巢癌患者和4例正常人卵巢组织及血清标本中miR-141的表达;检测4例良性卵巢肿瘤血清中miR-141的表达。结果：miR-141在卵巢癌患者组织中相对表达量分别为（72．846±76．671）显著高于正常人（2．869±3．201）（P〈0．05）;miR-141在卵巢癌患者血清中相对表达量（31．581±52．885）显著高于良性卵巢肿瘤患者（0．668±1．196）和正常人（1．690±1．697）（P〈0．05）,后两组间表达无差异（P〉0．05）;miR-141表达随卵巢癌临床分期的进展呈上升趋势（P〈0．01）,在无淋巴结转移组明显高于有淋巴结转移组（P〈0．05）,与组织分级和CA125的升高无关（P〉0．05）。在组织中miR-141表达水平与上皮性卵巢癌临床病理特征均未见明显差异（P〉0．05）。结论：miR-141可能在上皮性卵巢癌的发生发展中发挥癌基因的作用;miR-141用于检测上皮性卵巢癌敏感性和特异度较高,有望成为上皮性卵巢癌早期诊断的新指标。     

AnnexinⅠ蛋白在人前列腺癌中的表达及临床意义

目的：探讨AnnexinⅠ蛋白在前列腺癌组织中的表达及其与前列腺癌发生、发展、转移及预后的关系。方法：回顾性分析110例前列腺癌及40例前列腺增生组织中AnnexinⅠ蛋白的表达与前列腺癌Gleason分级、年龄、临床分期、转移及预后的相关性。结果：前列腺癌患者的AnnexinⅠ表达水平显著地低于良性前列腺增生症患者（P〈0．05）;AnnexinⅠ在低分化癌中表达较高,与高、中分化癌相比有显著性差异（P〈0．05）;而高、中分化癌之间AnnexinⅠ表达均较低,两者之间无显著性差异（P〉0．05）。前列腺癌AnnexinⅠ蛋白表达与年龄无关,而与临床分期、淋巴结转移及预后有关（P〈0．05）。结论：AnnexinⅠ蛋白表达下调与前列腺癌发生发展和预后密切相关,可作为反映前列腺癌生物学行为和判断预后的生物标记物.     

在HBV感染的肝癌组织中Fas/FasL表达的作用

目的探讨Fas／FasL（Fas配体）在原发性肝细胞肝癌（HCC）组织中的表达及其与乙肝病毒（HBV）感染的关系。方法用免疫组化S-P法检测21例肝癌组织及其10例癌旁组织Fas／FasL的表达。结果在肝癌和癌旁组织中Fas表达的阳性率分别为52．38％和80．00％（P〈0．05）,FasL分别为66．67％和40．00％（P〈0．05）。在HBsAg阳性和阴性组Fas表达的阳性率分别为50．00％和66．67％（P〉0．05）;FasL分别为61．11％和100％（P〈0．05）。肝癌组织中Fas、FasL表达与性别、年龄、肿瘤大小无关,与癌栓转移呈负相关,FasL与分化程度有关。结论肝癌细胞能下调Fas及上调FasL的表达而使凋亡受阻,HBV感染能抑制肝癌组织FasL的表达,可能是HBV在HCC的发牛及发展讨稃中的致痛机制。     

PSA在前列腺增生和前列腺癌中的诊断价值

目的：探讨临床上检测前列腺特异性抗原（PSA）的变化情况对前列腺增生和前列腺癌等疾病的诊断价值。方法：采用回顾性分析的方法,选取2010年6月至2012年4月在我院泌尿科接受治疗的前列腺增生患者64例定义为前列腺增生组（BPH）,前列腺癌患者83例定义为前列腺癌组（PCa）,另选取同期接受体检的健康人群137例作为对照组。分别检测三组患者入院时的游离前列腺特异性抗原和总前列腺特异性抗原的水平变化情况。对比并分析三组检测结果。结果：经检测,前列腺增生患者的血清总PSA明显高于对照组健康人群的正常值,而前列腺癌患者的血清总PSA比前列腺增生患者增高的更为明显。对照组游离PSA为（2．78±0．94）ng／mL,总PSA（1．05±0．57）ng／mL,游离PSA与总PSA的比值为,（0．38±0．61）;前列腺增生患者游离PSA为（6．36＋3．24）ng／mL,总PSA为（1．64±0．76）ng／mL,游离PSA与总PSA的比值为（0．26±0．23）;前列腺癌患者游离PSA为（12．42±4．97）ng／mL,总PSA为（1．44±0．78）ng／mL,游离PSA与总PSA的比值为（0．12±0．16）。组间比较差异明显,具有统计学意义（P〈0．05）。结论：对患者的PSA进行检测,对前列腺增生和前列腺癌的诊断具有良好的辅助作用和,临床价值。     

MMP-7和Survivin在结直肠癌中的表达及其临床意义

目的探讨Wnt信号通路中基质金属蛋白酶7（matrix melluoproteinases7,MMP-7）和凋亡抑制基因Survivin在结直肠癌组织中表达及其与临床病理特征的关系。方法应用免疫组织化学染色（Elivision）方法检测100例结直肠癌组织和60例癌旁正常黏膜组织中MMP-7和Survivin蛋白的表达。结果MMP-7蛋白在100例结直肠癌组织和60例癌旁正常黏膜组织中的阳性表达率分别为77．00％（77／100）和13．33％（8／60）,两组问差异有统计学意义（P〈0．01）;Survivin蛋白在100例结直肠癌组织和60例癌旁正常黏膜组织中的阳性表达率分别为65．00％（65／lOO）和15．00％（9／60）,两组问差异有统计学意义（P〈0．01）。MMP-7与Survivin蛋白阳性表达均与肿瘤的淋巴结转移和Dukes分期有关（P〈0．05）,此外,MMP-7蛋白在结直肠癌中的阳性表达也与肿瘤的浸润深度有关（P〈0．05）。而MMP-7与Survivin蛋白的阳性表达无相关性（r=0．097,P〉O．05）。结论MMP-7和Survivin在结直肠癌中的高表达可能与结直肠癌的发生、发展、浸润和转移等相关,检测癌组织中MMP-7和Survivin的表达有助于为结直肠癌的病情进展及预后判断提供帮助。     

缺血后处理对肺缺血／再灌注损伤的保护作用及其机制

目的：探讨缺血后处理（聃）是否通过抑制P38丝裂原活化蛋白激酶（P38MAPK）活化来减轻再灌注损伤肺细胞的凋亡。方法：雄性SD大鼠40只,随机分成5组（n=8）,即对照组（C组）、肺缺血／再灌注组（I／R组）、肺缺血／再灌注＋缺血后处理组（IPO组）、缺血后处理＋溶剂对照组（D组）、缺血后处理＋SB203580组（SB组）。各组分别于再灌注2h留取左肺组织,检测肺组织湿／干重比（W／D）和总肺含水量（TLW）;光镜观察肺组织形态学结构改变并进行肺组织损伤定量评估（IQA）;原住末端标记法（TUNEL）检测肺细胞凋亡情况并计算凋亡指数（AI）;RT-PCR和免疫组化法测定Bax、Bcl-2基因和蛋白的表达。结果：与C组相比,I／R组W／D、TLW、IQA和AI均显著升高（P〈0．05,P〈0．01）,肺组织结构发生明显损伤;Bcl-2、Bcl-2／Bax基因及蛋白表达明显降低,Bax基因及蛋白表达明显升高（P〈0．05,P〈0．01）;IPO组、D组、SB组与I／R组相比,w／D、TLW、IQA和AI均显著降低（P〈0．05,P〈0．01）,肺组织结构损伤情况有所改善;Bcl-2、Bcl-2／Bax基因及蛋白表达明显升高,Bax基因及蛋白表达明显降低（P〈0．05,P〈0．01）;D组与IPO组比较各项指标均无明显差异（均P〉0．05）;SB组与IPO组相比,肺组织W／D、TLW、IQA和AI均显著降低（P〈0．05,P〈0．01）,肺组织结构未见明显损伤;Bcl-2、Bcl-2／Bax基因及蛋白表达明显升高,Bax基因及蛋白表达明显降低（P〈0．05,P〈0．01）。结论：I／R通过激活P38MAPK导致大鼠肺泡结构严重破坏,肺内细胞大量凋亡;IPO可能是通过抑制P38MAPK通路的激活而减轻L／R损伤。     

VEGF—C和VEGFR-3在大肠癌中的表达及与淋巴结转移的关系

目的研究大肠癌患者癌组织中VEGF—C和VEGFR-3的表达及其相互之间的关系,以探讨VEGF—C和VEGFR-33大肠癌发生发展中的作用及与临床预后的关系。方法运用原位杂交方法及免疫组化SP法检测69例大肠癌组织中VEGF—CmRNA和VEGF—C的表达,同时运用免疫组化法分析相同组织中VEGFR-3表达状况。结果VEGF—CmRNA及VEGF—C在大肠癌组织中的表达阳性率分别为52．17％（36／69）和49．27％（34／69）,VEGF—C基因和蛋白表达基本相符合。VEGFR-3表达阳性率为43．48％（30／69）,正常黏膜未见VEGFR-3表达（P〈0．05）;大肠癌组织中VEGF—C与VEGFR-3蛋白表达之间存在显著的相关性（P〈0．01）。在伴有淋巴结转移的大肠腺癌中,VEGF—C与VEGFR～3的阳性表达率分别为67．74％（21／31）和64．52％（20／31）,转移组与非转移组相比较均有显著性差异（P〈0．01）;VEGF—C及VEGFR-3表达与Duke’s分期呈负相关（P〈0．05）,与组织分化、性别、年龄、肿瘤大小等临床病理因素无关（P〉0．05）。结论VEGF—C与VEGFR-3表达可增加大肠癌淋巴道转移和侵袭能力,其检测有助于大肠癌恶性程度评价及预后的判断,两者在大肠癌的发展中起重要作用。     

结直肠癌中Claudinl、ZEB-1和E-cadherin的表达及意义

目的探讨Claudinl、ZEB-1和E-cadherin在结直肠癌中的表达及三者之间的关系与临床病理的联系。方法免疫组织化学技术检测51例结直肠癌及癌旁组织中Claudinl、ZEB-1和E—cadherin蛋白的表达情况。结果在结直肠癌组织中Claudinl、ZEB-1、E—cadherin的表达率分别为68．6％、23．5％、56．9％,癌旁组织分别为37．3％、0、98．0％。三种蛋白在结直肠癌组织及癌旁组织中的表达差异均具有显著性（P〈O．01）。Claudinl及ZEB-1的表达率在III_IV期组（87．5％、41．7％）高于I-II期组（51．9％、7．4％;P〈0．01、P〈0．01）,有淋巴结转移组（90．9％、45．5％）高于无淋巴结转移组（51．7％、6,9％;P〈0．01、P〈0．01）,ZEB-1表达率在高级别组（42．1％）高于低级别组（12．5％;P〈0．05）。E—cadherin的表达率在I—II期组（74．1％）高于Ⅲ—IV期组（37．5％;P〈O．05）,无淋巴结转移组（72．4％）高于有淋巴结转移组（36．4％;P〈0．05）。Claudinl、ZEB-1与E-cadherin的表达均呈负相关（P〈0．05）,Claudinl与ZEB-1的表达呈正相关（P〈0．05）。结论Claudinl、ZEB-1和E-cadherin在结直肠癌发展,浸润和转移中起着重要作用,三者可能存在协同作用。     

GRP94和CD8在宫颈病变组织中的表达及意义

目的：探讨葡萄糖调节蛋白94（glucose—regulated protein94,GRP94）和CD8在宫颈病变组织中的表达及与HPV感染的关系。方法：采用免疫组化S—P法检测32例原发宫颈癌、27例宫颈上皮内瘤变（cervical intraepithelial neoplasia, CIN）及40例慢性宫颈炎组织中GRP94和CD8的表达及定位;采用western blot技术检测6例宫颈癌及6例正常宫颈组织中GRP94和CD8的表达。结果：①在宫颈癌、CIN2／3、CIN1及慢性宫颈炎组织中,GRP94的阳性表达率分别为87．5％、82．4％、40％和22．5％;CD8的阳性表达率分别为28．1％、64．7％、90％和97．5％;GRP94在宫颈癌和CIN2／3中的表达均显著高于慢性宫颈炎和CIN1组织（P均〈0．05）;CD8在宫颈癌组的表达显著低于慢性宫颈炎组、CIN1组及CIN2／3组（P均〈0．05）。②Western blot结果示GRP94在宫颈癌组织中的表达显著高于正常宫颈组织（P〈0．01）;CD8在宫颈癌组织中的表达显著低于正常宫颈组织（P〈0．01）。③GRP94的表达与宫颈癌分化程度、有无脉管侵袭有关（P〈0．05）,而与年龄、病理类型、临床分期及有无淋巴结转移无关（P〉0．05）;CD8的表达与有无脉管侵袭有关（P〈0．05）,而与年龄、病理类型、临床分期、分化程度及有无淋巴结转移无关（P〉0．05）。④宫颈病变组织中,GRP94的表达与HPV感染呈正相关（rs=0．377,P=0．000）;cD8的表达与HPV感染呈负相关（rs=-0．395,P=0．000）;GRP94与CD8的表达呈负相关（rs=-0．608,P=0．000）。结论：GRP94表达可能是宫颈CIN进展及宫颈癌预后判断的重要预测指标。     

PDGF-D、MPO与CD15在大肠癌中的表达及临床相关性研究

目的：探讨血小板源性生长因子D（PDGF-D）、髓过氧化物酶（MPO）YL粒细胞相关抗原（CD15）在大肠癌组织中的表达及其与临床特征之间的关系。方法：采用免疫组化染色方法检测88例大肠癌组织、72例大肠腺瘤组织及50例正常大肠粘膜组织中PDGF-D、MPO及CD15的表达情况。结果：PDGF—D、MPO、CD15在大肠癌组织中的阳性表达率分别为85．23％、63．64％、61．36％。PDGF—D、MPO在正常组、大肠腺瘤组和大肠癌组三者之间的表达均有显著性差异（P〈0．05）。CD15在正常组、大肠腺瘤组中的阳性表达率与大肠癌组中的阳性表达率有显著性差异（P〈0．05）,但在正常组与大肠腺瘤组中的阳性表达率无显著性差异（P〉0．05）。PDGF—D、MPO、CD15的表达在有淋巴结转移组织中的阳性率分别为92_31％、75．00％,73．08％;在无淋巴结转移组织中的阳性率分别为75．00％、52．78％,47．22％,三者在有无淋巴结转移组织中的阳性率均有显著性差异（P〈0．05）。PDGF．D、MPO、CD15在大肠癌中的表达与性别、年龄及组织分化程度均无相关（P〉0．05）。经Spearman相关性分析,PDGF—D及MPO在大肠癌的表达具有相关性（P〈O．05）。大肠癌中CD15与PDGF—D、MPO的表达无明显相关性（P〉0．05）：结论：PDGF—D、MPO与CDl5在大肠癌中的高表达,提示均参与了大肠癌的发生发展,可作为大肠癌恶性程度和侵袭转移的分子生物学标志物。     

Identification of Novel AR-Targeted MicroRNAs Mediating Androgen Signalling through Critical Pathways to Regulate Cell Viability in Prostate Cancer

MicroRNAs (miRNAs) have been recognized as significantly involved in prostate cancer (PCa). Since androgen receptor (AR) plays a central role in PCa carcinogenesis and progression, it is imperative to systematically elucidate the causal association between AR and miRNAs, focusing on the molecular mechanisms by which miRNAs mediate AR signalling. In this study, we performed a series of time-course microarrays to observe the dynamic genome-wide expressions of mRNAs and miRNAs in parallel in hormone-sensitive prostate cancer LNCaP cells stimulated by androgen. Accordingly, we introduced Response Score to identify AR target miRNAs, as well as Modulation Score to identify miRNA target mRNAs. Based on theoretical identification and experimental validation, novel mechanisms addressing cell viability in PCa were unravelled for 3 miRNAs newly recognized as AR targets. (1) miR-19a is directly up-regulated by AR, and represses SUZ12, RAB13, SC4MOL, PSAP and ABCA1, respectively. (2) miR-27a is directly up-regulated by AR, and represses ABCA1 and PDS5B. (3) miR-133b is directly up-regulated by AR, and represses CDC2L5, PTPRK, RB1CC1, and CPNE3, respectively. Moreover, we found miR-133b is essential to PCa cell survival. Our study gives certain clues on miRNAs mediated AR signalling to cell viability by influencing critical pathways, especially by breaking through androgen’s growth restriction effect on normal prostate tissue.     

Expression of Dicer and Its Related MiRNAs in the Progression of Prostate Cancer

Dicer is aberrantly expressed in several types of malignancies. Cleaved by Dicer, the small noncoding microRNAs (miRNAs) are considered potential tools for the diagnosis and prognosis of cancer. This study investigated the expression of miRNAs thought to target Dicer. Expression of 1,205 human miRNAs and miRNA*s were examined in four patients with prostate cancer (PCa) by miRNA array in which the threshold was set as two-fold. Seventy-three miRNAs and miRNA*s were significantly down-regulated while 10 were up-regulated in PCa tissues compared with matched histologically normal glands. Of these, miR-29b-1, miR-200a, miR-370, and miR-31, which were the most down/up-regulated and closely potentially target to the Dicer 3′ UTR, were investigated further. Tissues of primary tumors and matched normal prostate glands from 185 patients with PCa were collected for further investigation. Dicer mRNA levels were negatively correlated with miR-29b-1 (ρs = −0.177, p = 0.017), miR-200a (ρs = -0.489, p < 0.0001) and miR-31 (ρs = −0.314, p < 0.0001) expression. Compared with adjacent normal glands, PCa tissues showed significantly lower miR-200a and miR-31 expression levels. Furthermore, in metastatic PCa, the expression levels of miR-200a, miR-370, and miR-31 were dramatically higher than in localized PCa. Additionally, elevated expression levels of miR-200a and miR-31 appeared to be associated with castration-resistant PCa. These findings suggest possibilities that miR-200a and miR-31 target Dicer and are involved in the carcinogenesis, migration, and behavior of castration-resistant PCa, indicating that they could be potential biomarkers for monitoring PCa progression.     

miR-425-5p as an exosomal biomarker for metastatic prostate cancer

Prostate cancer-related deaths are mostly caused by metastasis, which indicates the importance of identifying clinical prognostic biomarkers. In this study, we evaluated the expression profile of exosomal microRNAs (miRNAs) derived from metastatic prostate cancer (mPCa) cell lines (LNCaP and PC-3). miRNA signatures in exosomes and cells were evaluated by miRNA microarray analysis. Fourteen miRNAs were identified as candidates for specific noninvasive biomarkers. The expression of five miRNAs was validated using RT-qPCR, which confirmed that miR-205-5p, miR-148a-3p, miR-125b-5p, miR-183-5p, and miR-425-5p were differentially expressed in mPCa exosomes. Bioinformatic analyses showed that miR-425-5p was associated with residual tumor, pathologic T and N stages, and TP53 status in PCa samples. Gene ontology analysis of negatively correlated and predicted targeted genes showed enrichment of genes related to bone development pathways. The LinkedOmics database indicated that the potential target HSPB8 has a significant negative correlation with miR-425-5p. In conclusion, this study identified a panel of exosomal miRNAs with potential value as prognostic biomarkers for prostate cancer.     

MicroRNA Profiling in Prostate Cancer - The Diagnostic Potential of Urinary miR-205 and miR-214

Prostate cancer (PCa) is the most common type of cancer in men in the United States, which disproportionately affects African American descents. While metastasis is the most common cause of death among PCa patients, no specific markers have been assigned to severity and ethnic biasness of the disease. MicroRNAs represent a promising new class of biomarkers owing to their inherent stability and resilience. In the present study, we investigated potential miRNAs that can be used as biomarkers and/or therapeutic targets and can provide insight into the severity and ethnic biasness of PCa. PCR array was performed in FFPE PCa tissues (5 Caucasian American and 5 African American) and selected differentially expressed miRNAs were validated by qRT-PCR, in 40 (15 CA and 25 AA) paired PCa and adjacent normal tissues. Significantly deregulated miRNAs were also analyzed in urine samples to explore their potential as non-invasive biomarker for PCa. Out of 8 miRNAs selected for validation from PCR array data, miR-205 (p<0.0001), mir-214 (p<0.0001), miR-221(p<0.001) and miR-99b (p<0.0001) were significantly downregulated in PCa tissues. ROC curve shows that all four miRNAs successfully discriminated between PCa and adjacent normal tissues. MiR-99b showed significant down regulation (p<0.01) in AA PCa tissues as compared to CA PCa tissues and might be related to the aggressiveness associated with AA population. In urine, miR-205 (p<0.05) and miR-214 (p<0.05) were significantly downregulated in PCa patients and can discriminate PCa patients from healthy individuals with 89% sensitivity and 80% specificity. In conclusion, present study showed that miR-205 and miR-214 are downregulated in PCa and may serve as potential non-invasive molecular biomarker for PCa.     

The clinical significance of circulating miR-21, miR-142, miR-143, and miR-146a in patients with prostate cancer

BackgroundProstate cancer (PCa) is the most common type of solid tissue cancer among men in western countries. In this study, we determined the levels of circulating miR-21, miR-142, miR-143, miR-146a, and RNU 44 levels as controls for early diagnosis of PCa.MethodsThe circulating miRNA levels in peripheral blood samples from 43 localized PCa patients, 12 metastatic PCa (MET) patients, and a control group of, 42 benign prostate hyperplasia (BPH) patients with a total of 97 volunteers were determined the by PCR method.ResultsNo differences in the DCT values were found among the groups. In PCa and PCaMet groups the expression of miR21 and miR142 were higher compared to the BHP group. No other differences were observed among the other groups. miR21 expression in the PCa group was 6.29 folds upregulated whereas in the PCaMet group 10.84 folds up-regulated. When the total expression of miR142 is evaluated, it showed a positive correlation with mir21 and mir 146 (both p<0.001). Also, the expression of miR146 shows a positive correlation with both miR21 and miR143 (both p<0.001). Expression of miRNAs was found to be an independent diagnostic factor in patients with Gleason score, PSA, and free PSA levels.ConclusionsOur study showed that co-expression of miR21, miR-142, miR-143, and miR-146a and the upregulation of miR-21 resulted in increased prostate carcinoma cell growth. In the PCaMet group, miR21 is the most upregulated of all miRNAs. These markers may provide a novel diagnostic tool to help diagnose PCa with aggressive behavior.     

The miRNA-kallikrein axis of interaction: a new dimension in the pathogenesis of prostate cancer

Kallikrein-related peptidases (KLKs) are a family of serine proteases that were shown to be useful cancer biomarkers. KLKs have been shown to be dysregulated in prostate cancer (PCa). microRNAs (miRNAs) are short RNA nucleotides that negatively regulate gene expression and have been reportedly dysregulated in PCa. We compiled a comprehensive list of 55 miRNAs that are differentially expressed in PCa from previous microarray analysis and published literature. Target prediction analyses showed that 29 of these miRNAs are predicted to target 10 KLKs. Eight of these miRNAs were predicted to target more than one KLK. Quantitative real-time (qRT)-PCR demonstrated that there was an inverse correlation pattern in the expression (normal vs. cancer) between dysregulated miRNAs and their target KLKs. In addition, we experientially validated the miRNA-KLK interaction by transfecting miR-331-3p and miR-143 into a PCa cell line. Decreased expression of targets KLK4 and KLK10, respectively, and decreased cellular growth were observed. In addition to KLKs, dysregulated miRNAs were predicted to target other genes involved in the pathogenesis of PCa. These data show that miRNAs can contribute to KLK regulation in PCa. The miRNA-KLK axis of interaction projects a new element in the pathogenesis of PCa that may have therapeutic implications.     

Epigenetic deregulation of miR-29a and miR-1256 by isoflavone contributes to the inhibition of prostate cancer cell growth and invasion

The epigenetic regulation of genes has long been recognized as one of the causes of prostate cancer (PCa) development and progression. Recent studies have shown that a number of microRNAs (miRNAs) are also epigenetically regulated in different types of cancers including PCa. In this study, we found that the DNA sequence of the promoters of miR-29a and miR-1256 are partly methylated in PCa cells, which leads to their lower expression both in PCa cells and in human tumor tissues compared with normal epithelial cells and normal human prostate tissues. By real-time PCR, Western Blot analysis and miRNA mimic and 3′-UTR-Luc transfection, we found that TRIM68 is a direct target of miR-29a and miR-1256 and that the downregulation of miR-29a and miR-1256 in PCa cells leads to increased expression of TRIM68 and PGK-1 in PCa cells and in human tumor tissue specimens. Interestingly, we found that a natural agent, isoflavone, could demethylate the methylation sites in the promoter sequence of miR-29a and miR-1256, leading to the upregulation of miR-29a and miR-1256 expression. The increased levels of miR-29a and miR-1256 by isoflavone treatment resulted in decreased expression of TRIM68 and PGK-1, which is mechanistically linked with inhibition of PCa cell growth and invasion. The selective demethylation activity of isoflavone on miR-29a and miR-1256 leading to the suppression of TRIM68 and PGK-1 expression is an important biological effect of isoflavone, suggesting that isoflavone could be a useful non-toxic demethylating agent for the prevention of PCa development and progression.