Role of miR-124 in the regulation of retinoic acid-induced Neuro-2A cell differentiation

Retinoic acid can cause many types of cells,including mouse neuroblastoma Neuro-2 A cells,to differentiate into neurons.However,it is still unknown whether microRNAs(miRNAs)play a role in this neuronal differentiation.To address this issue,real-time polymerase chain reaction assays were used to detect the expression of several differentiation-related miRNAs during the differentiation of retinoic acid-treated Neuro-2 A cells.The results revealed that miR-124 and miR-9 were upregulated,while miR-125 b was downregulated in retinoic acid-treated Neuro-2 A cells.To identify the miRNA that may play a key role,miR-124 expression was regulated by transfection of miRNA mimics or inhibitors.Morphological analysis results showed that inhibition of miR-124 expression reversed the effects of retinoic acid on neurite outgrowth.Moreover,miR-124 overexpression alone caused Neuro-2 A cells to differentiate into neurons,and its inhibitor could block this effect.These results suggest that miR-124 plays an important role in retinoic acid-induced differentiation of Neuro-2 A cells.

Nr2e1 Downregulation Is Involved in Excess Retinoic Acid-induced Developmental Abnormality in the Mouse Brain

Objective This study aimed to investigate the expression pattern and function of Nuclear receptor subfamily 2 group E member 1 （Nr2e1） in retinoic acid （RA）-induced brain abnormality. Methods The mouse model of brain abnormality was established by administering 28 mg/kg RA, and neural stem cells （NSCs） were isolated from the mouse embryo and cultured in vitro. Nr2e1 expression was detected by whole mount in situ hybridization, RT-PCR, and Western blotting. Nr2e1 function was determined by transducing Nr2e1 sh RNA into NSCs, and the effect on the sonic hedgehog （Shh） signaling pathway was assessed in the cells. In addition, the regulation of Nr2e1 expression by RA was also determined in vitro. Results Nr2e1 expression was significantly downregulated in the brain and NSCs of RA-treated mouse embryos, and knockdown of Nr2e1 affected the proliferation of NSCs in vitro. In addition, a similar expression pattern of Nr2e1 and RA receptor （RAR） α was observed after treatment of NSCs with different concentrations of RA. Conclusion Our study demonstrated that Nr2e1 could be regulated by RA, which would aid a better understanding of the mechanism underlying RA-induced brain abnormality.

Role of Acetylated p53 in Regulating the Expression of map2 in Retinoic Acid-induced P19 Cells

Objective To investigate the regulatory mechanisms of acetylated p53 in the expression of microtubule-associated protein-2(MAP2) in neuronal differentiation of P19 cells induced by all-trans retinoic acid(RA).Methods Neuronal differentiation of P19 cells was initiated with 4-day RA treatment.Immunofluorescence,real-time reverse transcription-polymerase chain reaction(RT-PCR) assay,and map2 promoter driven luciferase assay were performed to detect the expression and relative promoter activity of MAP2 in those RA-treated cells.Real-time PCR-based chromatin immunoprecipitation assay(ChIP) was carried out to reveal the specific recruitment of acetylated p53 onto its binding sites on map2 promoter.Results The expression of MAP2 was markedly increased in RA-induced P19 cells.The map2 mRNA increased 34-fold after 4 days of RA treatment and 730-fold 2 days after the treatment,compared with the cells without RA treatment(control).p53 was recruited to the promoter of map2 gene in acetylated form and thereby enhanced its promoter activity.p300/CBP associated factor(PCAF) was found induced in RA-treated cells and enriched in the nucleus,which might contribute to the acetylation of p53 in the regulation of map2 gene.Conclusions Acetylated p53 may participate in regulating the expression of map2 in RA-induced differentiation of P19 cells.PCAF is possibly involved in this process by mediating the acetylation of p53.

All-trans retinoic acid regulates the expression of MMP-2 and TGF-β2 via RDH5 in retinal pigment epithelium cells

·AIM: To investigate the effect of all-trans retinoic acid(ATRA) on retinol dehydrogenase 5(RDH5), matrix metalloproteinase-2(MMP-2) and transforming growth factor-β2(TGF-β2) transcription levels, and the effect of RDH5 on MMP-2 and TGF-β2 in retinal pigment epithelium(RPE) cells.·METHODS: After adult RPE cell line-19(ARPE-19 cells) intervened with gradient concentrations of ATRA(0-20 μmol/L) for 24h, flow cytometry was used to detect the proliferation and apoptosis of cells in each group, and quantitative realtime polymerase chain reaction(q RT-PCR) was used to detect RDH5, MMP-2 and TGF-β2 m RNA expression. Then, after ARPE-19 cells transfected with three different si RNA targets for 48h, the RDH5 knockdown efficiency of each group and expression of MMP-2 and TGF-β2 m RNA within them was detected by q RT-PCR. ·RESULTS: Flow cytometry results showed that ATRA could inhibit the proliferation of RPE cells and promote the apoptosis of RPE cells, and the difference of apoptosis was statistically significant when the ATRA concentration exceeded 5 μmol/L and compared with the normal control group(P=0.027 and P=0.031, respectively). q RT-PCR results showed that ATRA could significantly inhibit the expression level of RDH5 m RNA(P<0.001) and promote the expression of MMP-2 and TGF-β2 m RNA(P=0.03 and P<0.001, respectively) in a dose-dependent manner, especially when treated with 5 μmol/L ATRA. The knockdown efficiency of RDH5 si RNA varies with different targets, among which RDH5 si RNA-435 had the highest knockdown efficiency, i.e., more than 50% lower than that of the negative control group(P=0.02). When RDH5 was knocked down for 48h, the results of q RT-PCR showed that the expressions of MMP-2 and TGF-β2 m RNA were significantly up-regulated(P<0.001).·CONCLUSION: ATRA inhibits the expression of RDH5 and promotes MMP-2 and TGF-β2, and further RDH5 knockdown significantly upregulates MMP-2 and TGF-β2. These findings suggest that RDH5 may be involved in an epithelial-mesenchymal transition of RPE cells mediated by ATRA.

Expression of the retinoic acid-metabolizing enzymes RALDH2 and CYP26b1 during mouse postnatal testis development

Aim： To study the expression pattern of the retinoic acid metabolizing enzymes RALDH2 and CYP26bl during mouse postnatal testis development at both mRNA and protein levels. Methods： Real-time polymerase chain reaction and Western blot analysis were performed to determine the relative quantity of RALDH2 and CYP26bl at both mRNA and protein levels at postnatal day 1, 5, 10, 20, and in adult mice （70 days testes）. Testicular localization of RALDH2 and CYP26b 1 during mouse postnatal development was examined using immunohistochemistry assay. Results： Aldhla2 transcripts and its protein RALDH2 began to increase at postnatal day 10, and remained at a high level through postnatal day 20 to adulthood. Cyp2661 transcripts and CYP26bl protein did not change significantly during mouse postnatal testis development. RALDH2 was undetectable in the postnatal 1, 5 and 10 day testes using immunohis- tochemistry assay. At postnatal day 20 it was detected in pachytene spermatocytes. Robust expression of RALDH2 was restricted in round spermatids in the adult mouse testis. In the developing and adult testis, CYP26bl protein was confined to the peritubular myoepithelial cells. Conclusion： Our results indicate that following birth, the level of retinoic acid in the seminiferous tubules might begin to increase at postnatal day 10, and maintain a high level through postnatal day 20 to adulthood.

Retinoic Aacid Diminished the Expression of MMP-2 in Hyperoxia-exposed Premature Rat Lung Fibroblasts through Regulating Mitogen-activated Protein Kinases

This study examined the effects of retinoic acid （RA）, PD98059, SP600125 and SB203580 on the hyperoxia-induced expression and regulation of matrix metalloproteinase-2 （MMP-2） and metalloproteinase-2 （TIMP-2） in premature rat lung fibroblasts （LFs）. LFs were exposed to hyperoxia or room air for 12 h in the presence of RA and the kinase inhibitors PD98059 （ERK1/2）, SP600125 （JNK1/2） and SB203580 （p38） respectively. The expression levels of MMP-2 and TIMP-2 mRNA were detected by semi-quantitative reverse transcription polymerase chain reaction （RT-PCR）. MMP-2 activity was measured by zymography. The amount of p-ERK1/2, REK1/2, p-JNK1/2, JNK1/2, p-p38 and p38 was determined by Western blotting. The results showed that： （1） PD98059, SP600125 and SB203580 significantly inhibited p-ERK1/2, p-JNK1/2 and p-p38 respectively in LFs; （2） The expression of MMP-2 mRNA in LFs exposed to hyperoxia was decreased after treatment with RA, SP600125 and SB203580 respectively （P0.01 or 0.05）, but did not change after treatment with PD98059 （P0.05）. Meanwhile, RA, PD98059, SP600125 and SB203580 had no effect on the expression of TIMP-2 mRNA in LFs exposed to room air or hyperoxia （P0.05）; （3） The expression of pro- and active MMP-2 experienced no change after treatment with RA or SP600125 in LFs exposed to room air （P0.05）, but decreased remarkably after hyperoxia （P0.01 or 0.05）. SB203580 inhibited the expression of pro- and active MMP-2 either in room air or under hyperoxia （P0.01）. PD98059 exerted no effect on the expression of pro- and active MMP-2 （P0.05）. It was suggested that RA had a protective effect on hyperoxia-induced lung injury by down-regulating the expression of MMP-2 through decreasing the JNK and p38 activation in hyperoxia.

Prognostic Value of Promoter Hypermethylation of Retinoic Acid Receptor Beta (RARB) and CDKN2 (p16/MTS1) in Prostate Cancer

Objective: The molecular mechanism of prostate cancer is poorly understood. The aim of the study was to investigate the prevalence and prognostic value of promoter hypermethylation of retinoic acid receptor beta (RARB) and p16 among benign prostatic hyperplasia (BPH) and prostate cancer patients. Methods: In this case-control study, 63 patients were included in three groups; 21 with BPH as the control group, 21 with prostate cancer and good prognostic factors (based on prostate-specific antigen, Gleason score and stage) as good prognosis group, and 21 with prostate cancer and poor prognostic features as poor prognosis group. The prostate biopsy specimen of each individual was examined for hypermethylation of RARB and p16 promoters by methylation specific PCR (MSPCR). Results: Seven (33.3%) patients with good prognosis and 15 (71.4%) patients with poor prognosis were positive for RARB methylation, which were significantly higher than controls (P <0.0001). p16 promoter methylation was shown in 19.0% and 47.6% patients with good and poor prognosis, respectively. The RARB and p16 promoter methylation in the poor prognosis group was significantly higher than that in the good prognosis group (P =0.02 for RARB and P<0.0001 for p16). Conclusion: Hypermethylation of RARB and p16 promoters may predict prognosis in prostate cancer.

RARRES2's impact on lipid metabolism in triplenegative breast cancer:a pathway to brain metastasis

Breast cancer brain metastasis(BCBrM)is a crucial and hard area of research which guarantees an urgent need to understand the underlying molecular mechanisms.A recent study by Li et al.[1]published in Military Medical Research investigated the role of retinoic acid receptor responder 2(RARRES2)in regulating lipid metabolism in BCBrM,highlighting the clinical relevance of alterations in lipid metabolites,such as phosphatidylcholine(PC)and triacylglycerols(TAGs),by RARRES2 through the modulation of phosphatase and tensin homologue(PTEN)-mammalian target of rapamycin(mTOR)-sterol regulatory element-binding protein 1(SREBP1)signaling pathway.This commentary aims to elaborate on the key findings and their relevance to the field.

Molecular Cloning,Characterization and Expression Analysis of Woodchuck Retinoic Acid-Inducible GeneⅠ

Cytosolic retinoic acid-inducible gene I（RIG-I） is an important innate immune RNA sensor and can induce antiviral cytokines, e.g., interferon-β（IFN-β）. Innate immune response to hepatitis B virus（HBV） plays a pivotal role in viral clearance and persistence. However, knowledge of the role that RIG-I plays in HBV infection is limited. The woodchuck is a valuable model for studying HBV infection. To characterize the molecular basis of woodchuck RIG-I（w RIG-I）, we analyzed the complete coding sequences（CDSs） of w RIG-I, containing 2778 base pairs that encode 925 amino acids. The deduced w RIG-I protein was 106.847 k D with a theoretical isoelectric point（p I） of 6.07, and contained three important functional structures [caspase activation and recruitment domains（CARDs）, DEx D/H-box helicases, and a repressor domain（RD）]. In woodchuck fibroblastoma cell line（WH12/6）, w RIG-I-targeted small interfering RNA（si RNA） down-regulated RIG-I and its downstrean effector–IFN-β transcripts under RIG-I＇ ligand, 5＇-ppp double stranded RNA（ds RNA） stimulation. We also measured m RNA levels of w RIG-I in different tissues from healthy woodchucks and in the livers from woodchuck hepatitis virus（WHV）-infected woodchucks. The basal expression levels of w RIG-I were abundant in the kidney and liver. Importantly, w RIG-I was significantly up-regulated in acutely infected woodchuck livers, suggesting that RIG-I might be involved in WHV infection. These results may characterize RIG-I in the woodchuck model, providing a strong basis for further study on RIG-I-mediated innate immunity in HBV infection.

Induction of apoptosis and change of bcl-2 expression in macrophage Ana-1 cells by all-trans retinoic acid

Macrophage cells play an important role in the initiation and regulation of the immune response. All-trans retinoic acid (ATRA) and its natural and synthetic analogs (retinoids) affect a large number of biological processes.Recently , retinoids have been shown promise in the therapy and prevention of various cancers. However, many interesting questions related to the activities of retinoids remain to be answered: (Ⅰ) Molecular mechanisms by which retinoids exert their effects; (Ⅱ) why the clinical uses of retinoids give undesirable side effects of varying severity with a higher freqllency of blood system symptoms; (Ⅲ)little is known for its impacts on macrophage cells etc. We set up this experiment, therefore, to examine the apoptosis of ATRA on macrophage Ana-1 cell line. Apoptosis of the cells was quantitated, after staining cells with propidium iodide (PI), by both accounting nuclear condensation and flow cytometry. When the cells were treated with ATRA at or higher than 1 μM for more than 24 h, significant amount of the apoptotic cells was observed. Induction of apoptosis of Ana-1 cells by ATRA was in time- and dose-dependent manners, exhibiting the similar pattern as the apoptosis induced by actinomycin D (ACTD). ATRA treatment of Ana-1 cells also caused the changes of the mRNA levels of apoptosis-associated gene bcl-2, as detected by Northern blot analysis. The temporal changes of bcl-2 expression by ATRA was also parallel to that by ACTD. In conclusion,ATRA can induce apoptosis in macrophage cells, which may be helpful in understanding of immunological functions retinoids.

全反式维甲酸抑制核因子E2相关因子2和血红素加氧酶1加重大鼠肾脏缺血再灌注损伤表达

目的 观察用全反式维甲酸(all-trans retinoic acid,ATRA)抑制核因子E2相关因子2(Nrf2)和血红素加氧酶1(HO-1)是否会加重大鼠肾脏缺血再灌注损伤(IRI)表达。方法 2020年10月至2022年2月选取24只健康成年雄性SD大鼠切除右肾,并按随机数字表法分为3组(n=8),即假手术组(Sham)、肾脏缺血再灌注(I/R)组、全反式维甲酸(I/R+ATRA)组。其中Sham组和I/R组给予腹腔注射玉米油(1 m L·kg^(-1)·d^(-1))1周,ATRA组则给予腹腔注射溶于玉米油的ATRA(10 mg·kg^(-1)·d^(-1))1周后,3组大鼠用10%的水合氯醛(0.3 m L/100 g)进行麻醉后固定四肢,将其在37℃条件下沿腹中线打开腹腔并分离出左肾动脉。其中Sham组切除右肾,不予以夹闭左肾动脉;I/R组和ATRA组采用右肾切除联合左肾动脉夹闭45 min后再灌注24 h的方法建立大鼠肾脏I/R模型。实验结束后收集3组大鼠血清及肾组织标本,用比色法检测血清肌酐(Scr)、血尿素氮(BUN)浓度;HE染色法观察肾组织病理改变;TUNEL法进行肾组织细胞凋亡的检测;二氢乙啶(DHE)荧光染色评估肾组织活性氧的表达情况;通过比色法检测肾组织丙二醛(MDA)浓度、超氧化物歧化酶(SOD)活性;用蛋白质印迹法分别对Nrf2、HO-1的表达进行检测。结果 与Sham组相比,I/R组大鼠肾组织Nrf2、HO-1蛋白表达量均增加(P<0.01),活性氧表达量增加,SOD活性下降,MDA含量、血清Scr、BUN浓度升高(P<0.01),肾小管损伤评分及凋亡细胞表达较高(P<0.05),其中Nrf2蛋白和HO-1蛋白分别为0.52±0.09和0.37±0.79,高于Sham组的0.06±0.01和0.02±0.01。与I/R组相比,I/R+ATRA组大鼠肾组织Nrf2、HO-1蛋白显著减少(P<0.01),活性氧表达量明显增加,SOD活性严重下降,MDA含量、血清Scr、BUN浓度明显升高(P<0.01),肾小管损伤评分显著增加,肾脏凋亡细胞表达亦增高(P<0.05),其中I/R+ATRA组Nrf2蛋白和HO-1蛋白分别为0.29±0.04和0.15±0.03,显著低于I/R组。结论 Nrf2/HO-1通路参与肾脏缺血再灌注损伤过程,ATRA可能通过抑制Nrf2/HO-1通路,加重氧化应激,进一步加重肾脏缺血再灌注损伤。

Study of Bcl-2 siRNA Enhancement of Sensitivity of HL-60 Cells to All Trans Retinoic Acid

OBJECTIVE To study whether siRNA targeting against the Bcl-2 gene can enhance sensitivity of HL-60 cells to all trans retinoic acid(ATRA). METHODS siRNA,which is a leading sequence selected by previous experiments,was transferred into HL-60 cells.At 6 h after transfection,the cells were cultured with ATRA.The cell growth of the HL-60 cells was measured by the MTT assay at 24, 48,72 h.The level of the Bcl-2 protein and ROS(reactive oxygen species)as well as membrane potential of the mitochondria were determined by flowcytometry. RESULTS siRNA significantly increased the inhibitory effect of ATRA on growth of the HL-60 cells.The combination of siRNA with ATRA resulted in a decrease in the Bcl-2 protein level and an increase in the ROS level as well as significantly lowering the mitochondrial membrane potential of the HL-60 cells(P<0.05). CONCLUSION Effective siRNA targeting of Bcl-2 increases the sensitivity of HL-60 leukemic cells to ATRA by inhibiting the expression of the Bcl-2 protein.

Retinoic acid metabolic change in retina and choroid of the guinea pig with lens-induced myopia

AIM: To investigate the role of retinoic add (RA) and retinaldehyde dehydrogenase-2 (RALDH(2)) of retina and choroid in the guinea pig lens-induced myopic eyes. METHODS: Totally 45 guinea pigs, at age of three weeks, were randomly assigned into three groups: the normal control, the lens-induced group and the recovering group. Out of focus was induced by the -6.00D concave lens on the left eye, and lasted for 15 days. All animals underwent biometric measurement (corneal radius of curvature, refraction and axial length). Subsequently, RA content in the retina and RPE/choriod complex was detected by reversed-phase high-performance liquid chromatography. RALDH(2) protein in the retina and RPE/choriod complex was evaluated by the immunohistochemical staining and Western blotting. RESULTS: After wearing -6.00D lens for 15 days, axial length of the lens-induced eye extends and myopia was formed, with RA contents increasing in both the neural retina and RPE/choroid complex. Comparing with the lens-induced group, myopic degree significantly relieved, and its RA contents in both the neural retina and RPE/choroid complex decreased in the recovering group. In the normal control, RALDH(2) protein was expressed positively in the retinal nerve fiber layer (RNFL), inner plexiform layer (IPL) and lateral border of outer nuclear layer (ONL). Retinal RALDH(2) protein increased in the lens-induced group, and was also positive in the outer plexiform layer (OPL). In the recovering group, retinal RALDH(2) protein attenuated the expression in the OPL turns to negative. RALDH(2) protein was not expressed in the choroid of any group. CONCLUSION: RA of retina and chorid participates in the regulation of the lens-induced myopia in guinea pigs, which may be related with retinal RALDH(2) protein.

Effect of All-trans Retinoic Acid on Liver Fibrosis Induced by Common Bile Duct Ligation in Rats

The aim of this study was to investigate the effect and possible mechanism of all-trans retinoic acid （ATRA） on liver fibrosis induced by common bile duct ligation （CBDL） in rats. Fifty-three female Wistar rats were randomly divided into 5 groups： sham operation group （group J, 5 animals） and groups A, B, C and D （12 animals in each group）. The rats in groups A, B, C and D were subjected to CBDL to induce liver fibrosis, while those in group J to sham operation. From the 3rd week the rats in groups B, C and D respectively received daily administration of ATRA via gas- tric tube at three different doses [0.1, 1.5 and 7.5 mg/kg body weight （BW）]. Animals were sacrificed at 6th week. Rats＇ liver tissues were observed for pathologic changes under a light microscope. The protein levels of type Ⅰ collagen （COLⅠ）, matrix metalloproteinase-2 （MMP2）, MMP13 and tissue inhibitors of metalloproteinase-1 （TIMP-1） in liver tissues were determined by immunohistochemical techniques. The expression levels of TGF-β1 and CTGF mRNA in liver tissues were detected by semi-quantitative reverse transcription-polymerase chain reaction （RT-PCR）. The results showed that loss of normal hepatic architecture and formation of obvious fibrosis were observed in group A, while ATRA treatment for 4 weeks notably alleviated the pathological changes of hepatocytes. The expres- sion of COL Ⅰ and TIMP-1 proteins in group A was increased, while decreased in ATRA-treated CBDL groups （P〈0.05）. ATRA （1.5 and 7.5 mg/kg BW） reduced the expression levels of COLⅠ protein more greatly than that of 0.1 mg/kg BW （P〈0.05）. ATRA treatment increased the protein levels of MMP2 and MMP13. The expression levels of TGF-β1 and CTGF mRNA in group A were increased. In comparison with group A, the mRNA levels of TGF-β1 and CTGF in ATRA-treated CBDL groups were significantly decreased （P〈0.05）. It was concluded that ATRA could inhibit CBDL-induced liver fibrosis in rats by suppressing the expression of TGF-β1 and CTGF so as to di- minish the inhibition of TIMP-1 on MMP2 and MMP13 and increase the activity of MMP2 and MMP13.

Effects of retinoic acid and arotinoidethylester on expression of cyclins and cyclin-dependent kinase in HL-60 cells

HL-60 cells were synchronized from G1 to S phase boundary with a double thymidine block. Samples of the cells were collected at scheduled time points after the release of the block. It was found with immunoblot analysis that the protein expression of cyclin E and D, fluctuated periodically. They both began to increase in G, phase,reached the peak in S phase and declined gradually in G, phase. The protein expression of cyclin-dependent kinase P34cdk2 showed no periodical changes- The antiproliferation effect of retinoic acid or arotinoidethylester on HL-60cells was manifested by a block in Go/G1 of most of the cells and resulted in a marked decrease of the protein expression of cyclin E and D1 and no significant change of P34cdk2. These findings suggest that retinoic acid or arotinoidethylester is able to suppress the proliferation of HL-cells or to induce their differentiation.

CRABP2通过Wnt/β-catenin通路调控子宫内膜样腺癌细胞的增殖与侵袭

目的:探讨细胞视黄酸结合蛋白2(CRABP2)在子宫内膜样腺癌组织和细胞中的表达及其对子宫内膜样腺癌细胞增殖与侵袭的影响与其分子机制。方法:收集2020年6月至2021年4月在衡水市人民医院手术切除的子宫内膜样腺癌组织及配对正常子宫内膜组织,共24对;体外培养人子宫内膜样腺癌细胞An3ca、KLE。采用免疫组化分析及WB法检测子宫内膜样腺癌组织及正常子宫内膜组织中CRABP2的表达情况,采用WB法检测An3ca及KLE细胞中敲低CRABP2表达的效率,并以EDU法及Transwell实验检测敲低CRABP2表达后的An3ca及KLE细胞的增殖及侵袭能力,免疫荧光染色及WB法检测敲低CRABP2表达后的An3ca及KLE细胞中Wnt/β-catenin通路相关关键蛋白(β-catenin、c-Myc、cyclin-D1、MMP7及MMP9)的表达情况。以裸鼠体内成瘤实验观察敲低CRABP2表达对子宫内膜样腺癌细胞移植瘤生长和移植瘤组织中Ki67和β-catenin表达的影响。结果:与正常子宫内膜组织相比,CRABP2在人子宫内膜样腺癌组织中表达上调(P<0.01)。转染靶向CRABP2的shRNA后,An3ca、KLE细胞中CRABP2的表达降低(均P<0.01);敲低CRABP2表达后An3ca及KLE细胞增殖及侵袭能力均降低(均P<0.01),并且Wnt/β-catenin通路受到抑制(P<0.01)。成瘤实验显示敲低CRABP2表达后,裸鼠体内移植瘤体积明显缩小(P<0.01)。结论:CRABP2可通过调节Wnt/β-catenin通路发挥对子宫内膜样腺癌细胞增殖与侵袭的促进作用。

转谷氨酰胺酶2通过mTOR通路和自噬调控全反式维甲酸诱导的白血病细胞HL60和U937的髓系分化

全反式维甲酸(ATRA)是具有融合基因PML-RARα的急性早幼粒细胞白血病(APL)特异的靶向治疗药物。此外,ATRA在无PML-RARα融合的急性髓系白血病及其它一些肿瘤中也有一定治疗效果。但ATRA治疗也会引起一些并发症或发生愈后复发。因此,对ATRA诱导分化调控机制的研究非常重要。转谷氨酰胺酶2(TGM2)是一种多功能酶,能调控mTOR信号通路和自噬等。ATRA能诱导APL细胞中TGM2表达上调,TGM2敲低抑制ATRA诱导的细胞分化。但其调控机制及涉及的信号通路尚不明确。本研究发现,在HL60和U937细胞中,ATRA能够上调CD11b和TGM2的表达(P<0.05),抑制mTOR信号通路,并增强自噬;与对照相比,敲低TGM2,mTOR信号通路增强,自噬被抑制,而ATRA诱导的CD11b表达被抑制(P<0.05),分化减弱,被ATRA抑制的mTOR信号通路得到部分恢复,而被ATRA增强的自噬适当减弱。这表明ATRA使HL60和U937细胞发生髓系分化,并诱导TGM2表达升高;而TGM2通过mTOR信号通路和自噬途径调控ATRA诱导的髓系分化。该研究将有利于更深入地了解ATRA诱导白血病细胞分化的过程和机制,也有利于加深对TGM2的多功能性的认识;有助于对APL等白血病及其它癌症的药物诱导疗法的探讨。

上调RAI2表达抑制人子宫内膜癌细胞系HEC-1-A和KLE迁移与侵袭

目的检测上调维甲酸诱导基因2(retinoic acid-induced 2,RAI2)表达对子宫内膜癌细胞系迁移、侵袭能力的影响。方法选取子宫内膜癌细胞系HEC-1-A和KLE为研究对象,划痕实验、Transwell小室实验检测细胞迁移、侵袭能力。免疫荧光实验、Western blot检测RAI2、E-cadherin、vimentin的蛋白表达。结果子宫内膜癌细胞系HEC-1-A和KLE中RAI2表达水平上调后,LV-RAI2组子宫内膜癌细胞迁移与侵袭能力减弱(P<0.05),RAI2、E-cadherin表达水平升高,vimentin表达水平降低(P<0.05)。结论上调RAI2表达可能通过上皮间质转化调控抑制子宫内膜癌细胞迁移与侵袭能力。

外源性视黄酸对鸡后巩膜基质MMP-2表达作用的动态观察

注射后随时间延长眼轴及屈光度逐渐增加,不同时间组间差异极显著(P<0.01),MMP-2mRNA表达上调,不同时间组间差异无显著性(P>0.05)。自身对照组眼轴及屈光度均有增加,MMP-2mRNA表达较同龄正常对照组有轻度上调,组间差异极显著(P<0.01)。免疫组化显示,MMP-2表达的增高主要在巩膜成纤维细胞层。结论外源性视黄酸能够上调巩膜MMP-2的转录和表达,并可能通过这一途径促进眼轴及屈光度的增加。

骨形态发生蛋白受体2在维甲酸诱导腭裂小鼠胚胎腭突中的表达

目的探讨全反式维甲酸(at RA)对小鼠胚胎腭突中骨形态发生蛋白受体2(BMPR2)表达的影响。方法通过at RA灌胃的方法建立at RA诱导的小鼠腭裂模型,取妊娠15 d(GD15)和17 d的(GD17)的胚胎腭部进行苏木精-伊红染色,并用免疫组织化学及逆转录聚合酶链式反应技术检测BMPR2在胚胎腭部的表达。结果 at RA诱导小鼠形成体积较小的畸形腭突和明显的中缝腭裂畸形。BMPR2在GD15和GD17正常胚胎腭部有高水平的阳性表达,但在腭裂胚胎腭部的表达水平明显减弱。正常胚胎腭部Bmpr2 m RNA在GD15和GD17的表达水平均明显高于腭裂胚胎(P<0.05)。结论 at RA可导致小鼠胚胎腭突发育不良形成腭裂,并显著下调BMPR2表达水平,从而影响腭部发育的正常分子调控过程。