过表达miR-21的骨髓间充质干细胞在化疗性卵巢早衰大鼠模型中的治疗潜能及机制

目的:探讨过表达miR-21的BMMSCs对化疗性卵巢早衰的治疗作用及可能机制。方法:采用分子生物学方法构建miR-21慢病毒表达载体(LV-miR-21)。使用LV-miR-21转染体外分离培养的大鼠BMMSCs,获得过表达miR-21的BMMSCs(miR-21-BMMSCs)。建立化疗性卵巢早衰大鼠模型,双侧卵巢注射miR-21-BMMSCs,分别于注射后第15天、30天、45天、60天分批处死大鼠。采用阴道涂片测定动情周期,卵巢称重,HE染色进行卵泡计数,化学发光法测定性激素水平,TUNEL法测定卵巢颗粒细胞凋亡率,qRT-PCR、Western blot法检测miR-21及PTEN、PDCD4的mRNA及蛋白水平。结果:双侧卵巢注射miR-21-BMMSCs后,化疗诱导的POF大鼠动情周期恢复率、卵巢重量、各级卵泡数和E2水平增加,而FSH水平及卵巢颗粒细胞凋亡率下降。此外,miR-21表达水平的上升伴随PTEN、PDCD4 mRNA及蛋白水平的下降。结论:过表达miR-21的BMMSCs能更有效地治疗化疗性卵巢早衰,可能与其调控靶基因PTEN、PDCD4密切相关。     

顺铂诱导化疗损伤性卵巢早衰大鼠模型的探讨

目的:探讨顺铂诱导大鼠化疗损伤性卵巢功能早衰大鼠模型的可行性。方法:成熟雌性SD大鼠腹腔注射低、高剂量顺铂4.5 mg/kg(A组)、6.0 mg/kg(B组)和生理盐水(C组),每周1次,共2次,建立大鼠化疗损伤性卵巢早衰模型。检测血清FSH水平及光学显微镜下计数卵巢最大切面原始卵泡、初级卵泡、闭锁卵泡,阴道涂片观察动情周期变化。结果:A、B组大鼠动情周期均明显长于C组(P<0.05),并呈现剂量相关性改变。B组动情周期天数明显长于注射前(P<0.01);血清FSH水平A组与C组相比无统计学意义(P>0.05),B组明显高于A组和C组(P<0.05)。各顺铂组血清FSH水平注射后均较注射前明显升高(P<0.05)。腹腔注射顺铂后,A组、B组大鼠卵巢最大切面原始卵泡数和初级卵泡数均明显降低(P>0.05),而闭锁卵泡数均明显增加(P<0.05),并呈现剂量相关性改变。结论:顺铂可诱导化疗损伤性卵巢早衰。此化疗损伤性卵巢早衰大鼠模型血FSH明显升高,卵巢组织学衰退性改变与人类化疗损伤性卵巢早衰病变过程相似。     

骨髓间充质干细胞移植修复化疗所致卵巢损伤的实验研究

目的:探讨大鼠骨髓间充质干细胞(MSCs)移植对化疗所致卵巢损伤的影响。方法:采用腹腔注射环磷酰胺(CTX)建立化疗所致大鼠卵巢损伤模型,并随机分为模型组、实验对照组及移植组。同龄正常大鼠作为空白对照组。移植组在建模结束后每侧卵巢注射绿色荧光标记约1×106个MSCs。于移植后1、15、30、45天及60天,留取各组血标本,并于后4个时间点分批处死大鼠,留取卵巢标本。荧光显微镜下观察绿色荧光及其分布情况。阴道脱落细胞涂片观察大鼠动情周期的变化;以化学发光法检测雌二醇(E2)浓度,放射免疫法检测卵泡刺激素(FSH)浓度;计数各级卵泡数。结果:移植MSCs后15天,移植组卵巢组织内可见到明亮的绿色荧光,持续至移植后2月。绿色荧光分布在卵巢间质组织。移植组30%(6/20)的大鼠在移植后15~30天内恢复正常的动情周期,在移植后30~60天内又有4只大鼠恢复正常的动情周期。移植后15、30、45天和60天时,移植组E2浓度高于实验对照组相应时间点E2浓度,而FSH浓度则低于实验对照组相应时间点FSH浓度,差异有显著性。移植45、60天时,移植组各级卵泡数目均高于模型组和实验对照组,低于空白对照组。结论:骨髓间充质干细胞可以在环磷酰胺损伤的大鼠卵巢组织中存活、迁移,但其分化为卵泡组分的可能性小。骨髓间充质干细胞移植可修复环磷酰胺损伤的卵巢组织,部分改善卵巢内分泌功能。     

MiR-190在原发性卵巢功能不全模型小鼠中的差异表达

目的:采用环境化学物质VCD构建原发性卵巢功能不全(POI)小鼠模型,探讨miR-190表达在POI发病中的机制。方法:选取连续两个动情周期正常的20只昆明雌性小鼠,随机分为空白组、模型组。模型组:连续15天腹腔注射环境化学物质VCD构建POI模型。ELISA法检测两组小鼠血清AMH水平,观察两组小鼠动情周期和卵巢组织形态学变化。实时荧光定量PCR技术检测两组小鼠卵巢组织中miR-190表达水平。结果:模型组经腹腔注射VCD后均有动情周期紊乱,且以动情间期为主。模型组小鼠镜下见卵巢明显萎缩,皮质增厚,可见较多闭锁卵泡,原始卵泡及各级发育中的卵泡消失或偶见。与空白组相比,模型组小鼠卵巢miR-190表达明显升高,差异有统计学意义(P0.01)。结论:运用环境化学物质VCD可成功建立POI模型小鼠,POI的发病机制可能与卵巢miR-190过度表达有关。     

米非司酮诱导大鼠PCOS动物模型的实验研究

目的:建立抗孕激素米非司酮诱导成年雌性SD大鼠多囊卵巢综合征(P-COS)动物模型,并探讨其意义。方法:选择4～5天规律动情周期的成年雌性SD大鼠,于动情周期第一天皮下注射米非司酮并阴道涂片监测动情周期,8天后称重大鼠,取出卵巢,称重并观察大体解剖及光镜(HE)改变,测定血清LH、T、FSH、E2水平。结果:(1)用药后第4天动情周期开始失去规律性,阴道上皮呈持续角化,提示无排卵。(2)大鼠体重及卵巢单位重量明显增加(P<0.01)。(3)肉眼观察:大鼠卵巢表面的卵泡明显扩张,卵巢色泽及白膜厚度未见明显异常。镜下观察:大鼠卵巢白膜下见多个呈囊性扩张的卵泡及闭锁卵泡,颗粒细胞层减少至2～3层,卵泡内卵母细胞或放射冠消失,黄体数量明显下降并伴有不完全的黄素化。(4)血清LH、T、E2显著升高(P<0.01),FSH浓度降低,但差异无统计学意义(P=0.094)。结论:米非司酮诱导的成年雌性大鼠PCOS模型在内分泌和卵巢形态学的改变与PCOS患者相似,是较理想的PCOS模型。     

人羊水来源干细胞治疗大鼠卵巢早衰的初步研究

目的:尾静脉注射移植人羊水干细胞(AFS),评价其治疗大鼠卵巢早衰(POF)的效果。方法:采用SD大鼠,按体重随机分为四组:A组正常组、B组模型组、C组一次移植组和D组两次移植组,除A组灌胃生理盐水外,其余各组均连续14天灌胃雷公藤多苷片;C组在第14天灌胃后移植一次AFS,D组在第1天与第7天灌胃后移植两次AFS;观察大鼠阴道涂片、血清性激素水平、大鼠卵巢及子宫组织形态学变化。结果:(1)B组动情周期较A组显著延长,C组与D组均有不同程度恢复,D组恢复状况优于C组;(2)HE染色结果显示,D组大鼠卵巢均有新生卵泡;(3)性激素检测结果显示,各组之间E2值差异均有统计学意义(P均<0.01)。结论:AFS对POF有修复作用,可能通过促进卵泡生成,调节雌激素分泌,从而改善了卵巢功能。     

雄激素致无排卵大鼠卵巢转化生长因子β1及其受体的变化

目的:探讨雄激素致无排卵大鼠卵泡发育的影响。方法:建立雄激素致无排卵大鼠模型,并设正常对照组,放免法测定血清睾酮(T),HE染色观察卵巢组织形态学变化,免疫组化法检测卵巢转化生长因子β1及其受体(TGFβ1/TGFβ1R)的表达。结果:①模型组血清T水平明显高于对照组;②模型组大鼠卵巢中卵泡囊状扩张,颗粒细胞层极薄;而对照组可见发育期各级卵泡及黄体形成;③模型组卵巢颗粒细胞、卵泡膜细胞、间质细胞TGFβ1/TGFβ1R的表达明显高于对照组。结论:雄激素致无排卵大鼠卵巢颗粒细胞、卵泡膜细胞、间质细胞TGFβ1/TGFβ1R的表达明显增高可能是导致卵泡发育障碍、无排卵的因素之一。     

PCOS大鼠血清中miR-200b及靶基因VEGF的表达及临床意义

目的:研究miR-200b及靶基因血管内皮生长因子(VEGF)在多囊卵巢综合征(PCOS)大鼠血清中的表达水平,探讨miR-200b及VEGF在PCOS发病机制中的作用。方法:选取60只6周龄SD雌性大鼠,随机分为实验组、对照组和空白组,每组各20只。实验组给予来曲唑灌胃制备PCOS大鼠模型,观察大鼠动情周期及卵巢形态学变化。放射免疫法测定大鼠血清黄体生成激素(LH)、卵泡刺激素(FSH)、雌二醇(E_2)、孕酮(P)和睾酮(T)水平。采用实时荧光定量聚合酶链反应(real-time PCR)法检测miR-200b及VEGF的表达。结果:与对照组比较,实验组大鼠失去规律的动情周期,其卵巢体积增大,镜下呈现多囊样改变,血清T、LH水平明显升高,FSH、E2、P水平显著下降(均P0.01)。real-time PCR实验结果显示miR-200b在PCOS大鼠模型血清中的表达显著降低(P0.01),靶基因VEGF在PCOS大鼠模型血清中的表达显著升高(P0.01)。结论:miR-200b在PCOS大鼠模型血清中低表达,可能通过调控其靶基因VEGF而在PCOS发病机制中起重要作用,推测miR-200b可成为诊断PCOS的生物学标志物,从而为PCOS的诊治提供新思路。     

人脐血单个核细胞移植对卵巢早衰大鼠卵巢功能的影响

目的本研究旨在探讨人脐血单个核细胞(HCMNCs)在大鼠卵巢早衰模型中的修复作用,以期为临床细胞治疗卵巢早衰提供一种理论和实验依据。方法(1)建立卵巢早衰模型;(2)确定POF造模成功;(3)利用Ficoll密度梯度离心法制备HCMNCs细胞悬液;(4)将大鼠随机分为三组:A组大鼠不予任何处置,B组大鼠双侧卵巢各注入10■细胞悬液,C组将等量的L-DMEM培养基注入大鼠的双侧卵巢;(5)利用ELISA方法检测血清E2、FSH、LH水平,卵巢组织切片进行HE染色,观察卵巢未闭锁卵泡数量及卵巢形态学情况。结果HCMNCs细胞悬液移植后50 d:(1)B组大鼠动情周期紊乱率较C组有明显的减少,阴道脱落细胞涂片开始有上皮细胞、角化细胞、白细胞等多样细胞交替的变化;(2)B组血清E2水平较C组升高,两者差异有高度统计学意义(P0.001);LH、FSH水平较C组LH、FSH水平降低,两者差异有高度统计学意义(P0.001);(3)卵巢病理切片形态学观察B组未闭锁卵泡数目较C组明显增多,差异有高度统计学意义(P0.001)。结论人脐血单个核细胞参与修复受损卵巢的功能,可缓解低雌激素的状态,对卵巢早衰的治疗起到积极的作用。     

TNF-α对去子宫大鼠卵巢颗粒细胞凋亡的影响

目的 探讨TNF-α对去子宫大鼠卵巢颗粒细胞凋亡的影响。方法 应用子宫切除术建立去子宫Sprague—Dawley大鼠模型。体外培养卵巢颗粒细胞并加60ng／ml外源性TNF-α。应用荧光显微镜、流式细胞仪检测细胞凋亡情况。结果 模型组较正常对照组凋亡增加；TNF-α组较模型组凋亡进一步加剧。结论 外源性TNF-α促进去子宫大鼠卵巢颗粒细胞凋亡。提示TNF-α可能加速了子宫切除所致卵巢早衰过程。     

微小RNA-21表达在卵巢癌细胞生长和凋亡过程中的作用

目的;探讨微小RNA-21( miR-21)在卵巢癌细胞生长、凋亡中的作用及调节机制。方法构建表达miR-21的重组干扰载体pSIREN-miR-21质粒,采用酶切鉴定和测序法证实。实验分为3组,即转染组：卵巢癌细胞株OVCAR3细胞转染重组干扰载体pSIREN-miR-21质粒;阴性对照组：OVCAR3细胞转染阴性对照pSIREN-miR-21-Neg质粒;空白对照组：OVCAR3细胞不转染质粒。采用茎环实时荧光定量逆转录(RT)-PCR技术检测3组细胞中miR-21的表达,蛋白印迹法检测3组细胞中程序性细胞死亡因子4( PDCD4)蛋白的表达,四甲基偶氮唑蓝(MTT)比色法及流式细胞仪检测3组细胞的增殖及凋亡情况。结果成功构建了表达miR-21的重组干扰载体pSIREN-niR-21质粒,并经酶切鉴定和测序法证实。转染组、阴性对照组和空白对照组OVCAR3细胞中niR-21的表达水平分别为0.26±0.08、1.26±0.21和1.00,转染组明显低于阴性对照组和空白对照组,差异有统计学意义(P＜0.01)。转染组、阴性对照组和空白对照组OVCAR3细胞中PDCD4蛋白的灰度值分别为1443 ±33、858±19和846±16,转染组明显高于阴性对照组和空白对照组,差异有统计学意义(P＜0.01)。转染组、阴性对照组和空白对照组OVCAP3细胞增殖的A值分别为0.661±0.015、0.848±0.150、0.935±0.133,转染组明显低于阴性对照组和空白对照组,差异有统计学意义(P＜0.01)。转染48 h后,转染组细胞的早期凋亡率明显高于阴性对照组和空白对照组[分别为(25.821±0.763)％、(0.010 ±0.003)％、(0.238±0.023)％;P ＜0.01];转染72 h后,转染组细胞的早期凋亡率和晚期凋亡率均明显高于阴性对照组和空白对照组[早期凋亡率分别为( 30.480±0.821)％、(7.792±0.312)％、(7.033±0.257)％,P＜0.01;晚期凋亡率分别为(3.558±0.211)％、(1.557±0.067)％、(1.049±0.028)％,P＜0.05]。结论miR-21参与调节卵巢癌细胞的生长和凋亡过程,可能通过调控PDCD4蛋白的表达而发挥作用。     

Profiling of differentially expressed microRNAs in premature ovarian failure in an animal model

Premature ovarian failure (POF) contributes to amenorrhoea, infertility, early onset of menostasia and osteoporosis. This study profiled differentially expressed miRNAs for association with POF development. Ovarian tissue samples from 4-vinylcyclohexene diepoxide (VCD)-induced rat POF and normal rats were profiled for differentially expressed miRNAs using miRNA microarrays. A total of 63 miRNAs were up-regulated and 20 miRNAs were down-regulated in rat POF tissues versus the control tissues. qRT-PCR verified some of these altered miRNAs, i.e. miR-29a and miR-144 were down-regulated in POF tissues, which may target expression of PLA2G4A that is involved in prostaglandin biosynthesis, whereas miR-27b and miR-190 were up-regulated in POF tissues by negative control of PAPPA and CCL2 expression, respectively, both of which have been shown to relate to response to hormone stimulus. Moreover, the up-regulated miR-151 and miR-672 can also target expression of TNFSF10 and FNDC1, which have been shown to positively regulate cell apoptosis. Profiling of differentially expressed miRNAs in POF provided a novel insight into the molecular events involving the role of miRNAs in POF development with specific emphasis upon miR-27b, miR-190, miR-151, miR-672, miR-29a and miR-144.     

Hyperandrogen enhances apoptosis of human ovarian granulosa cells via up-regulation and demethylation of PDCD4

Abstract

Apoptosis of granulosa cells (GCs) induced by hyperandrogen plays a key role in the pathogenesis of polycystic ovary syndrome (PCOS). However, the mechanism of androgen-induced apoptosis of GCs has not been clarified to date. Recent studies have reported that PDCD4 expression is higher in PCOS patients and might be a key factor in PCOS progression. In this study, we aimed to investigate the role of PDCD4 in regulating apoptosis of human GCs and whether hyperandrogen regulate PDCD4 expression through DNA methylation. Overexpression of PDCD4 in human ovarian granulosa cell line KGN cells promoted cells apoptosis. Meanwhile, expression of caspase-3 and caspase-9 were significantly elevated. High concentration of testosterone treatment resulted in up-regulation of PDCD4 and a significant increase of apoptosis in KGN cells. In addition, knockdown of PDCD4 in KGN cells treated with high concentration of testosterone abolished the hyperandrogen-induced apoptosis. Furthermore, high concentration of testosterone down-regulated DNMT1, DNMT3A and DNMT3B expression and the methylation level in the promoter region of PDCD4 was decreased. In conclusion, PDCD4 can promote apoptosis of human ovarian GCs. The mechanism of hyperandrogen-induced apoptosis may be mediated by PDCD4. Furthermore, the up-regulation of PDCD4 induced by hyperandrogen may through demethylation of its promoter regions.     

MiR-21 is Enriched in the RNA-Induced Silencing Complex and Targets COL4A1 in Human Granulosa Cell Lines

MicroRNAs (miRNAs) are noncoding small RNAs that play important roles in a variety of physiological and pathological events. In this study, we performed large-scale profiling of EIF2C2-bound miRNAs in 3 human granulosa-derived cell lines (ie, KGN, HSOGT, and GC1a) by high-throughput sequencing and found that miR-21 accounted for more than 80% of EIF2C2-bound miRNAs, suggesting that it was enriched in the RNA-induced silencing complex (RISC) and played a functional role in human granulosa cell (GC) lines. We also found high expression levels of miR-21 in primary human GCs. Assuming that miR-21 target mRNAs are enriched in RISC, we performed cDNA cloning of EIF2C2-bound mRNAs in KGN cells. We identified COL4A1 mRNA as a miR-21 target in the GC lines. These data suggest that miR-21 is involved in the regulation of the synthesis of COL4A1, a component of the basement membrane surrounding the GC layer and granulosa-embedded extracellular structure.     

The inhibition of miR-21 promotes apoptosis and chemosensitivity in ovarian cancer

Background

MicroRNAs have been implicated in tumorigenesis, drug resistance, and prognosis in cancer. We investigated the role of microRNA-21 (miR-21) in regulating ovarian cancer drug resistance.

Methods

We used parental and cisplatin resistant ovarian cell lines to demonstrate the role of miR-21 in drug resistance and investigated the gene targets of miR-21. Fresh tumor specimens were used to validate our in vitro findings.

Results

Cisplatin resistant ovarian cells were four-fold more resistant compared to the parental cell line. MiR-21 was overexpressed in the resistant cell line on microRNA microarray, which was subsequently validated with qRT-PCR. Using anti-microRNA inhibitors, we demonstrated that miR-21 attenuation reversed the drug resistant phenotype in both the resistant and parental cell lines. The inhibition of miR-21 induced apoptosis based on annexin V-FITC immunostaining. Using Western blot analysis, miR-21 knockdown enhanced the expression of tumor suppressor PDCD4, and attenuated apoptosis inhibitor c-IAP2. Using 101 specimens from advanced ovarian cancer patients enrolled in The Cancer Genome Atlas, we found that women with tumors that overexpressed miR-21 were associated with a shorter progression-free survival.

Conclusion

Our data suggest that miR-21 regulates drug resistance via apoptosis and cellular survival pathways. Targeting miR-21 may have clinical utility in the treatment of resistant ovarian cancer.     

Circulating auto-antibodies against the zona pellucida and thyroid microsomal antigen in women with premature ovarian failure

Premature ovarian failure (POF) is a disorder of multicausal etiology leading to infertility in women. Development of ovarian auto-antibodies is a causative factor in most POF cases, but no consensus on the ovarian antigenic determinants has been reached till date. In the present study, sera from 15 POF cases, seven normally cycling women and eight menopausal women were studied by immunohistochemistry (IHC) for the presence of anti-ovarian antibodies. 10 of the 15 POF sera (66.6%) presented with anti-ovarian antibodies (Ao). Of these, two demonstrated antibodies to the zona pellucida (ZP) as well as strong immunoreactivity to granulosa cells (Azg), while the remaining eight exhibited anti-ZP antibodies with negligible staining in granulosa cells (Az). The antibodies showed cross-reactivity with ZP from various species such as human, sheep, marmoset, pig and mouse. Among various murine tissues, the antibodies cross-reacted only with thyroid and not with uterus, spleen, kidney, liver, adrenal, pancreas and pituitary. Five of the eight Az individuals presented with significant titres of anti-thyroid antibodies (Azt). In the control group, one menopausal control presented with reactivity to both ZP and GC, the autoimmunity possibly being a consequence of surgical trauma; while one normally cycling woman tested positive for anti-thyroid antibodies. The IHC results were confirmed by ELISA using heat-solubilized isolated ZP (SIZP) as the antigen. Out of seven Ao samples assessed by ELISA, five reacted with SIZP. Preincubation of these five samples with varying concentrations of SIZP demonstrated a dose-dependent decrease in reactivity in ELISA and abolished staining in IHC, confirming the specificity of auto-antibodies to ZP in the POF group. Our results thus suggest that ZP is an important ovarian antigen in autoimmune POF.     

妊娠期肝内胆汁淤积症患者血清中miR-21和IGFBP-3的表达及与围生儿结局的关系

目的:探讨妊娠期肝内胆汁淤积症(ICP)患者血清中微小RNA-21(miR-21)和胰岛素样生长因子结合蛋白3(IGFBP-3)的表达及两者与围生儿结局的关系。方法:选取四川省妇幼保健院收治的62例ICP患者作为研究组,同期健康体检孕妇62例为对照组,收集产前静脉血,采用实时荧光定量聚合酶链反应(qRT-PCR)检测血清中miR-21和IGFBP-3的相对表达量,比较两者相关性及与围生儿结局的关系。结果:研究组孕妇血清miR-21表达水平高于对照组,IGFBP-3表达水平低于对照组,差异有统计学意义(均P<0.05)。ICP患者血清中miR-21表达水平与IGFBP-3表达水平呈负相关(r=-0.783,P=0.000)。miR-21高表达组患者早产、剖宫产、羊水粪染发生率均高于miR-21低表达组,分娩孕周和新生儿出生体质量低于miR-21低表达组,差异有统计学意义(均P<0.05)。2组新生儿窒息和胎死宫内发生率比较,差异无统计学意义(均P>0.05)。IGFBP-3低表达组患者早产、剖宫产、羊水粪染发生率均高于IGFBP-3高表达组,分娩孕周和新生儿出生体质量低于IGFBP-3高表达组,差异有统计学意义(均P<0.05)。2组新生儿窒息和胎死宫内发生率比较,差异无统计学意义(均P>0.05)。结论:ICP患者血清中miR-21表达升高,IGFBP-3表达降低,二者呈负相关,miR-21高表达和IGFBP-3低表达患者围生儿不良结局发生率高,临床中应加以重视。     

Role of transient hyperprolactinemia in the late follicular phase of the gonadotropin-stimulated cycle

Background: Serum prolactin (PRL) concentration is known to transiently increase in rats; however, its change is obscure and the role of it is also unclear in women. We studied the relationship between estradiol (E₂) and PRL production and the role of transient hyperprolactinemia in the late follicular phase of the gonadotropin-stimulated cycle.
Methods: (1) Serum E₂ and PRL concentrations were measured on an early follicular day and immediately before a human chorionic gonadotropin (hCG) injection in 60 patients with normoprolactinemia. Twelve of the 60 patients also received a gonadotropin injection with bromocriptine, and serum hormone levels were compared with those without bromocriptine. (2) Preovulatory serum E₂ and PRL concentrations were compared between the natural and clomiphene treatment cycles in 14 hormonally normal women. (3) Changes of serum PRL concentrations were measured before and after E₂ loading in five premature ovarian failure (POF) patients. (4) The E₂ production by granulosa cells in the presence of PRL was measured.
Results and Conclusion: Serum E₂ and PRL concentrations were significantly increased by the gonadotropin injection. Bromocriptine treatment completely inhibited the PRL increase, but further increased serum E₂ concentration on the late follicular day. The E₂ loading increased serum PRL levels in POF patients. The clomiphene treatment increased serum E₂ but decreased PRL concentrations. Prolactin significantly decreased E₂ production by granulosa cells. A feedback loop may exist between E₂ and PRL to control the excess E₂ production induced by gonadotropin injection. (Reprod Med Biol 2002; 1 : 69–74)     

The anti-chemoresistant effect and mechanism of MUC1 aptamer–miR-29b chimera in ovarian cancer

Objective

Currently, there are no effective therapies for advanced ovarian cancer. In this study, we aim to determine the anti-tumor effect of MUC1 aptamer–miR-29b chimera in xenograft ovarian cancer models and chemo-resistance tumor model and to further explore the associated mechanism.

Methods

Xenograft ovarian cancer animal models were established using OVCAR-3, OVCA420, and OVCAR-3-Taxol cancer cells. The chimera (Chi-29b) was delivered through intraperitoneal injections. Tumor growth was evaluated. Gene expression and PTEN methylation were measured.

Results

We demonstrated that intratumoral injection of Chi-29b chimera significantly inhibited the growth of xenograft OVCAR-3 tumors through downregulating PTEN methylation, subsequent PTEN expression, as well as downregulating MAPK 4 and IGF1 expressions. In contrast, Chi-29b inhibited tumor growth in OVCA420 tumors by downregulating MAPK 4 & 10 and IGF1 expression without affecting PTEN expression. Intraperitoneal injection of Chi-29b significantly increased apoptosis in paclitaxel-resistant OVCAR-3 cells and inhibited the growth of xenograft OVCAR-3-Taxol tumors. The anti-chemoresistant role of Chi-29b in OVCAR-3-Taxol tumors was associated with the activation of PTEN signaling and downregulation of MAPK 4 and 10 and IGF1 expression.

Conclusion

Our study indicated that Chi-29b chimera can effectively exert an anti-tumor effect in xenograft tumor models and an anti-chemoresistant role through inhibiting cancer stem cell activation.