棕色田鼠睾丸及附睾胚后发育的形态学变化

通过组织学方法,对产后1 d、10 d、25 d、45 d、60 d及70 d的棕色田鼠Lasiopodomys mandarinus睾丸和附睾发育进行了观察,以探讨其精子发生特点.结果 发现,1 d棕色田鼠的生殖细胞主要是生殖母细胞和前精原细胞;10 d出现大量精原细胞,睾丸间质细胞明显;25 d出现精子细胞;45 d有少量精子出现;60 d和70 d具有各级生精细胞,睾丸生精小管和附睾内出现大量成熟精子.睾丸生精小管管径和生精上皮厚度随日龄增加,于60 d达到最大;附睾管腔直径和附睾上皮厚度也于60 d达到最大.这些结果表明,棕色田鼠在生后45 d左右进入青春期,60 d左右达到性成熟,精子的产生及成熟与附睾的发育同步.     

中心体蛋白Cenexin在大鼠精子发生过程中的表达特征

中心体蛋白Cenexin是成熟中心粒的唯一标志分子。为阐明中心粒在大鼠精子发生过程中的成熟以及功能,我们首先通过RT-PCR技术从大鼠睾丸组织中扩增出了Cenexin cDNA片段,原核表达重组蛋白后,用其免疫小鼠制备了高滴度的抗Cenexin的多克隆抗体,然后利用免疫荧光染色、Western Blot和半定量RT-PCR方法,研究了大鼠精子发生过程中Cenexin蛋白和基因的表达特征。结果显示Cenexin mRNA水平在精原细胞和精母细胞中较高,随后表达水平下降,而蛋白质分子在精原细胞到精子细胞中都定位于细胞的一个中心粒上,表示有成熟中心粒的存在,在长形精子细胞中该蛋白位于鞭毛的基体部。附睾的绝大多数成熟精子中Cenexin免疫染色消失。中心体蛋白Cenexin在精子变态期的表达变化可能与精子鞭毛形成的起始有关。     

中心体蛋白Cenexin在大鼠精子发生过程中的表达特征

中心体蛋白Cenexin是成熟中心粒的唯一标志分子。为阐明中心粒在大鼠精子发生中的成熟以及功能,我们首先通过RT－PCR技术从大鼠睾丸组织中扩增出了Cenexin cDNA片段,原核表达重组蛋白后,用其免疫小鼠制备了高滴度的抗Cenexin的多克隆抗体,然后利用免疫荧光染色、Western Blot和半定量RT－PCR方法,研究了大鼠精子发生过程中Cenexin蛋白和基因的表达特征。结果显示Cenexin mRNA水平在精原细胞和精母细胞中较高,随后表达水平下降,而蛋白质分子在精原细胞到精子细胞中都定位于细胞的一个中心粒上,表示有成熟中心粒的存在,在长形精子细胞中该蛋白位于鞭毛的基体部。附睾的绝大多数成熟精子中Cenexin免疫染色消失。中心体蛋白Cenexin在精子变态期的表达变化可能与精子鞭毛形成的起始有关。     

丝氨酸/精氨酸蛋白特异激酶SRPK2在小鼠睾丸组织中的表达及意义

目的通过研究丝氨酸/精氨酸蛋白特异激酶2(serine/arginine-rich protein specific kinase 2,SRPK2)基因mRNA及其编码蛋白产物在小鼠睾丸组织中的表达特征,探讨该基因在精子发生过程中的作用及意义。方法分别采用半定量逆转录聚合酶链反应(RT-PCR)和蛋白免疫印迹杂交(Western blotting)分析该基因mRNA及蛋白产物在小鼠多种组织中的表达;利用实时定量PCR(real-time quantitative PCR)分析SRPK2 mRNA在不同发育阶段小鼠睾丸组织中的差异表达;应用免疫组织化学染色和间接免疫荧光技术观察SRPK2蛋白在小鼠曲精小管中的细胞定位和生精细胞内的亚细胞定位。结果半定量RT-PCR和Western blotting分析显示SRPK2 mRNA和蛋白在小鼠睾丸组织中均大量表达;实时定量PCR分析发现SRPK2 mRNA在5周及8周龄雄性小鼠睾丸组织中显著表达,具有明显的阶段特异性表达特征。免疫组织化学染色结果表明SRPK2蛋白阳性着色主要位于曲精小管中的长形精子细胞核;间接免疫荧光分析显示SRPK2蛋白定位于长形精子细胞核表面。结论 SRPK2基因在小鼠睾丸组织中大量表达,并且具有显著的阶段特异性表达特征和明确的细胞核定位,极有可能在小鼠精子发生的变态成形期参与mRNA前体分子的剪接过程,其作用机制值得进一步深入研究。     

秦岭北坡中国林蛙精巢显微结构的年周期变化

用光镜观察了秦岭北坡中国林蛙(Ranachensinensis)精巢显微结构的年周期变化,结合精巢系数的变化探讨其生殖规律。结果显示,秦岭北坡中国林蛙的生精周期属于非连续型。精巢系数的变化与精子发生的活动周期相一致。精子发生从每年5月开始,翌年4月结束,历时1年。生精周期可划分为5个时期。Ⅰ期,精原细胞增殖期,5～7月,精巢系数最小,精原细胞进行有丝分裂;Ⅱ期,精母细胞成熟分裂期,8～9月,精巢系数最大,精原细胞、精母细胞和精子细胞在生精小管内共存;Ⅲ期,精子形成期,9～1 0月,精子细胞变态形成精子;Ⅳ期,成熟精子贮存越冬期,1 1月至翌年2月,成熟精子贮存在生精小管中;V期,精子排放期,翌年3～5月,精巢系数显著下降,成熟精子从生精小管脱离,通过输精管道排出体外。     

不同病理睾丸组织中雄激素受体和热休克蛋白90α表达的差异

目的检查和分析不同病理睾丸组织雄激素受体和热休克蛋白90α表达的差异.方法运用免疫组织化学二步法检查精子发生停滞、精原细胞瘤、前列腺癌去势和正常健康睾丸标本之雄激素受体和热休克蛋白90α的表达情况.结果正常睾丸组织和前列腺癌去势睾丸中雄激素受体在间质细胞、支持细胞和精原细胞的胞核表达,前者的表达强度高于后者(P<0.05);热休克蛋白90α主要在类肌细胞、间质细胞、支持细胞核及生精细胞的胞浆表达.精子发生阻滞的睾丸组织,雄激素受体主要在支持细胞的胞核和生精细胞的胞浆表达,热休克蛋白90α主要在支持细胞、类肌细胞表达;精原细胞瘤的睾丸组织,雄激素受体在肿瘤细胞的胞浆和胞核表达,热休克蛋白90α的表达强度在精原细胞瘤组织高于对照标本.结论雄激素受体核转运异常与精子发生阻滞有紧密关系;前列腺癌去势患者睾丸组织中,雄激素受体免疫反应强度减弱与睾丸衰老有关;精原细胞瘤患者睾丸标本,雄激素受体表达减弱,但热休克蛋白90α表达增强;提示雄激素受体和热休克蛋白90α的表达异常与精原细胞瘤的病理发生有关.     

雷帕霉素对人胰腺癌细胞SW1990的mTOR信号通路的影响

目的:研究雷帕霉素对人胰腺癌细胞SW1990的mTOR信号通路的影响。方法:采用免疫细胞化学证实mTOR信号通路的存在,通过CCK-8法研究雷帕霉素对胰腺癌细胞增殖的影响,通过Western blot和real time PCR分别从蛋白水平和基因水平研究雷帕霉素对mTOR及其下游分子的表达。结果:免疫细胞化学结果显示p-mTOR、p-p70S6K、p-4E-BP1在细胞质中均呈阳性;CCK-8法显示雷帕霉素能明显抑制细胞增殖(P<0.05);Western blot结果显示随着雷帕霉素浓度的增加,p-mTOR、p-p70S6K表达明显减少,而p-4E-BP1蛋白表达明显增加(P<0.05);Real-time PCR结果显示随雷帕霉素浓度的增加,CyclinD1、VEGF、c-myc基因表达明显减少(P<0.05)。结论:人胰腺癌细胞系SW1990中存在mTOR信号通路并处于激活状态;雷帕霉素抑制胰腺癌细胞增殖与雷帕霉素抑制mTOR信号通路活化有关。     

粗糙沼虾精巢发育的组织学

利用光镜技术,对粗糙沼虾精巢发育进行了研究,根据精子发生过程中每种生殖细胞所占的比例和发生的次序,并结合精巢的形态特征,把精巢发育过程分为五个时期,即精原细胞期,精母细胞期,精细胞期,成熟精子期及退化期,精原细胞期,精巢小,透明乳白色,生精小管内的生殖细胞以精原细胞为主;精母细胞期;精巢体积增大,半透明乳白色,主要由处于初级精母细胞的次级精母细胞阶段的生殖细胞组成;精细胞期,精巢体积继续增大,颜色加深,生精小管内的生殖细胞以精细胞为主;成熟精子期,精巢体积可达最大,紫红色,生精小管内充满着成熟的精子,退化期;精巢体积减小,半透明乳白色,生精小管内的成熟精子几乎排空。     

调控睾丸支持细胞增殖和分化的信号通路研究进展

支持细胞是睾丸内的一类重要细胞,能为生精过程提供转运蛋白、调节蛋白、生长因子等数十种细胞因子,参与生精细胞成熟分化的调控,对睾丸内各级生殖细胞的迁移、增殖和分化具有重要的支持作用。研究表明,在Wnt/β-catenin信号通路中,关键蛋白β-catenin的适度激活能促进睾丸支持细胞的增殖、分化;在mTOR信号通路中,mTOR基因的缺失导致睾丸支持细胞的数量减少;在TGF-β信号通路中,不同浓度的TGF-β细胞因子影响睾丸支持细胞的增殖、分化。由此可见,Wnt/β-catenin信号通路、mTOR信号通路和TGF-β信号通路在睾丸支持细胞的增殖和分化中均具有重要的调控作用。对这三条信号通路调节支持细胞增殖分化的机制以及它们之间的相互作用作一综述,旨在为深入研究调控睾丸支持细胞增殖的信号机制提供理论依据,从而进一步为雄性生育的调控及生殖方面的疾病治疗提供新思路和新方法。     

生精冲剂对白消安致生精障碍大鼠恢复精子发生及其机理的研究

为研究生精冲剂对精子发生的作用,我们随机将30只雄性SD大鼠分为正常组、药物组和对照组.后2组通过腹腔注射白消安制备成生精障碍模型大鼠.药物组每天灌胃生精冲剂,对照组灌胃等量的生理盐水.连续30 d后,测定血清FSH、LH、T水平和睾丸组织切片观察的结果显示,药物组大鼠血清中3种激素的水平与对照组相比差异显著(P＜0.05),并可在睾丸组织切片的曲细精管中,观察到大量的精原细胞和圆形精子细胞,而对照组中只有少量的精原细胞,半定量RT-PCR分析结果表明,生精冲剂促进了GDNF表达.因此,生精冲剂对精子发生有明显的促进作用.     

Stem cell factor/c-kit up-regulates cyclin D3 and promotes cell cycle progression via the phosphoinositide 3-kinase/p70 S6 kinase pathway in spermatogonia

Stem cell factor (SCF)/c-kit plays an important role in the regulation of hematopoiesis, melanogenesis, and spermatogenesis. In the testis, the SCF/c-kit system is believed to regulate germ cell proliferation, meiosis, and apoptosis. Studies with type A spermatogonia in vivo and in vitro have indicated that SCF induces DNA synthesis and proliferation. However, the signaling pathway for this function of SCF/c-kit has not been elucidated. We now demonstrate that SCF activates phosphoinositide 3-kinase (PI3-K) and p70 S6 kinase (p70S6K) and that rapamycin, a FRAP/mammalian target of rapamycin-dependent inhibitor of p70S6K, completely inhibited bromodeoxyuridine incorporation induced by SCF in primary cultures of spermatogonia. SCF induced cyclin D3 expression and phosphorylation of the retinoblastoma protein through a pathway that is sensitive to both wortmannin and rapamycin. Furthermore, AKT, but not protein kinase C-zeta, is used by SCF/c-kit/PI3-K to activate p70S6K. Dominant negative AKT-K179M completely abolished p70S6K phosphorylation induced by the constitutively active PI3-K catalytic subunit p110. Constitutively active v-AKT highly phosphorylated p70S6K, which was totally inhibited by rapamycin. Thus, SCF/c-kit uses a rapamycin-sensitive PI3-K/AKT/p70S6K/cyclin D3 pathway to promote spermatogonial cell proliferation.     

Visfatin exerts angiogenic effects on human umbilical vein endothelial cells through the mTOR signaling pathway

The biologically active factors known as adipocytokines are secreted primarily by adipose tissues and can act as modulators of angiogenesis. Visfatin, an adipocytokine that has recently been reported to have angiogenic properties, is upregulated in diabetes, cancer, and inflammatory diseases. Because maintenance of an angiogenic balance is critically important in the management of these diseases, understanding the molecular mechanism by which visfatin promotes angiogenesis is very important. In this report, we describe our findings demonstrating that visfatin stimulates the mammalian target of the rapamycin (mTOR) pathway, which plays important roles in angiogenesis. Visfatin induced the expression of hypoxia-inducible factor 1α (HIF1α) and vascular endothelial growth factor (VEGF) in human endothelial cells. Inhibition of the mTOR pathway by rapamycin eliminated the angiogenic and proliferative effects of visfatin. The visfatin-induced increase in VEGF expression was also eliminated by RNA interference-mediated knockdown of the 70-kDa ribosomal protein S6 kinase (p70S6K), a downstream target of mTOR. Visfatin inactivated glycogen synthase kinase 3β (GSK3β) by phosphorylating it at Ser-9, leading to the nuclear translocation of β-catenin. Both rapamycin co-treatment and p70S6K knockdown inhibited visfatin-induced GSK3β phosphorylation at Ser-9 and nuclear translocation of β-catenin. Taken together, these results indicate that mTOR signaling is involved in visfatin-induced angiogenesis, and that this signaling leads to visfatin-induced VEGF expression and nuclear translocation of β-catenin.     

Glutamine is a key regulator for amino acid-controlled cell growth through the mTOR signaling pathway in rat intestinal epithelial cells

Amino acids, especially branched-chain amino acids such as l-leucine, have been shown to regulate activation of p70 S6 kinase and phosphorylation of 4E-BP1 through the mTOR signaling pathway. In our recent study, l-arginine was also shown to activate the mTOR signaling pathway in rat intestinal epithelial cells. l-Glutamine is an amino acid that is required for culturing of numerous cell types, including rat intestinal epithelial cells. In this study, we showed that l-glutamine inhibited the activation of p70 S6 kinase and phosphorylation of 4E-BP1 induced by arginine or leucine in rat intestinal epithelial cells. Although the molecular mechanism of l-glutamine-induced inhibition of the mTOR signaling pathway is still unknown, the presence of this novel signal pathway may indicate that individual amino acids play specific roles for cellular proliferation and growth.     

Group I metabotropic glutamate receptors activate the p70S6 kinase via both mammalian target of rapamycin (mTOR) and extracellular signal-regulated kinase (ERK 1/2) signaling pathways in rat striatal and hippocampal synaptoneurosomes

Group I metabotropic glutamate receptors (mGluRs) have been demonstrated to play a role in synaptic plasticity via a rapamycin-sensitive mRNA translation signaling pathway. Various growth factors can stimulate this pathway, leading to the phosphorylation and activation of mammalian target of rapamycin (mTOR), a serine/threonine protein kinase that modulates the activity of several translation regulatory factors, such as p70S6 kinase. However, little is known about the cellular and molecular mechanisms that bring the plastic changes of synaptic transmission after stimulation of group I mGluRs. Here, we investigated the role of the mTOR-p70S6K and the ERK1/2-p70S6K pathways in rat striatal and hippocampal synaptoneurosomes after group I mGluR stimulation. Our findings show that (S)-3,5-dihydroxyphenylglycine (DHPG) increases significantly the activation of mTOR and p70S6K (Thr389, controlled by mTOR) in both brain areas. The mTOR activation is dose-dependent and requires the stimulation of mGluR1 subtype receptors as for the p70S6K activation observed in striatum and hippocampus. In addition, the p70S6K (Thr421/Ser424) activation via the ERK1/2 activation is increased and involved also mGluR1 receptors. These results demonstrate that group I mGluRs are coupled to mTOR-p70S6K and ERK1/2-p70S6K pathways in striatal and hippocampal synaptoneurosomes. The translational factor p70S6K could be involved in the group I mGluRs-modulated synaptic efficacy.     

Osteoprotegerin inhibit osteoclast differentiation and bone resorption by enhancing autophagy via AMPK/mTOR/p70S6K signaling pathway in vitro

Osteoclasts are highly differentiated terminal cells formed by fusion of hematopoietic stem cells. Previously, osteoprotegerin (OPG) inhibit osteoclast differentiation and bone resorption by blocking receptor activator of nuclear factor-κB ligand (RANKL) binding to RANK indirect mechanism. Furthermore, autophagy plays an important role during osteoclast differentiation and function. However, whether autophagy is involved in OPG-inhibited osteoclast formation and bone resorption is not known. To elucidate the role of autophagy in OPG-inhibited osteoclast differentiation and bone resorption, we used primary osteoclast derived from mice bone marrow monocytes/macrophages (BMM) by induced M-CSF and RANKL. The results showed that autophagy-related proteins expression were upregulated; tartrate-resistant acid phosphatase-positive osteoclast number and bone resorption activity were decreased; LC3 puncta and autophagosomes number were increased and activated AMPK/mTOR/p70S6K signaling pathway. In addition, chloroquine (as the autophagy/lysosome inhibitor, CQ) or rapamycin (as the autophagy/lysosome inhibitor, Rap) attenuated osteoclast differentiation and bone resorption activity by OPG treatment via AMPK/mTOR/p70S6K signaling pathway. Our data demonstrated that autophagy plays a critical role in OPG inhibiting osteoclast differentiation and bone resorption via AMPK/mTOR/p70S6K signaling pathway in vitro.     

Effects of PI3K catalytic subunit and Akt isoform deficiency on mTOR and p70S6K activation in myoblasts

The PI3K/Akt/mTOR signaling pathway is critical for cellular growth and survival in skeletal muscle, and is activated in response to growth factors such as insulin-like growth factor-I (IGF-I). We found that in C2C12 myoblasts, deficiency of PI3K p110 catalytic subunits or Akt isoforms had distinct effects on phosphorylation of mTOR and p70S6K. siRNA-mediated knockdown of PI3K p110α, p110β, and simultaneous knockdown of p110α and p110β resulted in increased basal and IGF-I-stimulated phosphorylation of mTOR S2448 and p70S6K T389; however, phosphorylation of S6 was reduced in p110β-deficient cells, possibly due to reductions in total S6 protein. We found that IGF-I-stimulated Akt1 activity was enhanced in Akt2- or Akt3-deficient cells, and that knockdown of individual Akt isoforms increased mTOR/p70S6K activation in an isoform-specific fashion. Conversely, levels of IGF-I-stimulated p70S6K phosphorylation in cells simultaneously deficient in both Akt1 and Akt3 were increased beyond those seen with loss of any single Akt isoform, suggesting an alternate, Akt-independent mechanism that activates mTOR/p70S6K. Our results collectively suggest that mTOR/p70S6K is activated in a PI3K/Akt-dependent manner, but that in the absence of p110α or Akt, alternate pathway(s) may mediate activation of mTOR/p70S6K in C2C12 myoblasts.     

Silencing of RHEB inhibits cell proliferation and promotes apoptosis in colorectal cancer cells via inhibition of the mTOR signaling pathway

Colorectal cancer (CRC) is commonly known as one of the most prominent reasons for cancer-related death in China. Ras homolog enriched in brain (RHEB) and the mammalian target activity of rapamycin (mTOR) signaling pathway were found correlated with CRC, but their specific interaction in CRC was still to be investigated. Therefore, we explored whether RHEB gene silencing affected the cell proliferation, differentiation, and apoptosis by directly targeting the mTOR signaling pathway in cells previously harvested from CRC patients. A microarray analysis was subsequently conducted to investigate the relationship between RHEB and mTOR. Eighty-three adjacent normal tissues and CRC tissues were selected. Immunohistochemistry was carried out to detect the positive expression rates of RHEB and Ki-67 in the CRC tissues. Cells were then transfected with different siRNAs to investigate the potential effects RHEB would have on CRC progression. The expressions of RHEB, 4EBP1, ribosomal protein S6 kinase (p70S6K), proliferating cell nuclear antigen (PCNA), B cell lymphoma 2 (bcl-2), and bcl-2-associated X protein (bax) were determined and then the cell cycle, cell proliferation, and apoptotic rate were also measured. We identified RHEB and mTOR as upregulated genes in CRC. Cells treated with RHEB silencing showed a decreased extent of mTOR, p70S6K, 4EBP1 phosphorylation and expression of RHEB, Ki-67, mTOR, p70S6K, 4EBP1, bcl-2, and PCNA as well as decreased activity of cell proliferation and differentiation; although, the expression of bax was evidently higher. Collectively, our data propose the idea that RHEB gene silencing might repress cell proliferation and differentiation while accelerating apoptosis via inactivating the mTOR signaling pathway.     

A role for Raptor phosphorylation in the mechanical activation of mTOR signaling

The activation of mTOR signaling is necessary for mechanically-induced changes in skeletal muscle mass, but the mechanisms that regulate the mechanical activation of mTOR signaling remain poorly defined. In this study, we set out to determine if changes in the phosphorylation of Raptor contribute to the mechanical activation of mTOR. To accomplish this goal, mouse skeletal muscles were subjected to mechanical stimulation via a bout of eccentric contractions (EC). Using mass spectrometry and Western blot analysis, we found that ECs induced an increase in Raptor S696, T706, and S863 phosphorylation, and this effect was not inhibited by rapamycin. This observation suggested that changes in Raptor phosphorylation might be an upstream event in the pathway through which mechanical stimuli activate mTOR. To test this, we employed a phospho-defective mutant of Raptor (S696A/T706A/S863A) and found that the EC-induced activation of mTOR signaling was significantly blunted in muscles expressing this mutant. Furthermore, mutation of the three phosphorylation sites altered the interactions of Raptor with PRAS40 and p70^S6k, and it also prevented the EC-induced dissociation of Raptor from p70^S6k. Combined, these results suggest that changes in the phosphorylation of Raptor play an important role in the pathway through which mechanical stimuli activate mTOR signaling.     

Extracellular ATP-induced proliferation of adventitial fibroblasts requires phosphoinositide 3-kinase, Akt, mammalian target of rapamycin, and p70 S6 kinase signaling pathways

Extracellular nucleotides are increasingly recognized as important regulators of growth in a variety of cell types. Recent studies have demonstrated that extracellular ATP is a potent inducer of fibroblast growth acting, at least in part, through an ERK1/2-dependent signaling pathway. However, the contributions of additional signaling pathways to extracellular ATP-mediated cell proliferation have not been defined. By using both pharmacologic and genetic approaches, we found that in addition to ERK1/2, phosphatidylinositol 3-kinase (PI3K), Akt, mammalian target of rapamycin (mTOR), and p70 S6K-dependent signaling pathways are required for ATP-induced proliferation of adventitial fibroblasts. We found that extracellular ATP acting in part through G(i) proteins increased PI3K activity in a time-dependent manner and transient phosphorylation of Akt. This PI3K pathway is not involved in ATP-induced activation of ERK1/2, implying activation of independent parallel signaling pathways by ATP. Extracellular ATP induced dramatic increases in mTOR and p70 S6K phosphorylation. This activation of the mTOR/p70 S6 kinase (p70 S6K) pathway in response to ATP is because of independent contributions of PI3K/Akt and ERK1/2 pathways, which converge on the level of p70 S6K. ATP-dependent activation of mTOR and p70 S6K also requires additional signaling inputs perhaps from pathways operating through Galpha or Gbetagamma subunits. Collectively, our data demonstrate that ATP-induced adventitial fibroblast proliferation requires activation and interaction of multiple signaling pathways such as PI3K, Akt, mTOR, p70 S6K, and ERK1/2 and provide evidence for purinergic regulation of the protein translational pathways related to cell proliferation.     

Retracted: MicroRNA-99b suppresses human cervical cancer cell activity by inhibiting the PI3K/AKT/mTOR signaling pathway

Cervical cancer is common cancer among women with high morbidity. MicroRNAs (miRs) are involved in the progression and development of cervical cancer. This study aimed to explore the effect of miR-99b-5p (miR-99b) on invasion and migration in cervical cancer through the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mechanistic target of rapamycin (mTOR) signaling pathway. The microarray-based analysis was used to screen out differentially expressed miRNAs. Expression of miR-99b, PI3K, AKT, mTOR, and ribosomal protein S6 kinase (p70S6K) was determined in both cervical cancer tissues and paracancerous tissues. Next, alteration of miR-99b expression in cervical cancer was conducted to evaluate levels of PI3K, AKT, mTOR, p70S6K matrix metallopeptidase 2, epithelial cell adhesion molecule, and intercellular adhesion molecule 1, as well as the effect of miR-99b on cell proliferation, invasion, migration, cell cycle distribution, and apoptosis. The results demonstrated that miR-99b expression was decreased and levels of PI3K, AKT, mTOR, and p70S6K were elevated in cervical cancer tissues. More important, overexpressed miR-99b repressed the PI3K/AKT/mTOR signaling pathway, inhibited cell proliferation, invasion, and migration, blocked cell cycle entry, and promoted apoptosis in cervical cancer. These results indicate that miR-99b attenuates the migration and invasion of human cervical cancer cells through downregulation of the PI3K/AKT/mTOR signaling pathway, which provides a therapeutic approach for cervical cancer treatment.