TET1 partially mediates HDAC inhibitor-induced suppression of breast cancer invasion.

Histone deacetylases (HDACs) are important in chromatin remodeling and epigenetic regulation of gene expression. Histone deacetylase inhibitors (HDACi) have highly effective anti-metastatic and anti-angiogenic activity in various types of cancer, while the molecular mechanisms involved in this process are not fully understood. In the present study, trichostatin A (TSA), a HDACi, was found to suppress MCF-7 breast carcinoma cell invasion and upregulate TET1 expression in a dose-dependent manner. TET1, a dioxygenase involved in cytosine demethylation, is downregulated during breast cancer progression. TET1 knockdown in MCF-7 cells facilitates cell invasion, inhibits the expression of tissue inhibitors of metalloproteinase 2/3 (TIMP2/3) and promotes matrix metalloproteinases (MMP) 2/9 transcriptional activity. Importantly, TET1 depletion impaired the inhibitory effect of TSA on breast cancer cell invasion. Together, these results illustrated a mechanism by which TET1 partially mediates HDACi elicited suppression of breast cancer invasion.

Inhibitory effect of platelet-derived growth factor-α receptor silencing on the proliferation of human lens epithelial cell / 中华实验眼科杂志

Background Platelet-derived growth facto(PDGF) affectthe proliferation of human lenepithelial cell(LECs),and human LECexpresPDGF-α recepto(PDGFR-α) throughoutheilifetime.The binding of activated PDGF-α receptowith PDGF promotethe synthesiof DNA.Othestudiedemonstrated thasilencing of PDGFR-α by antisense oligodeoxynucleotide(ASODN) inhibitthe growth of RPE cellin proliferative vitreoretinopathy (PVR),buwhethethitechnique ifeasible foLECiunclear.Objective Thistudy wato investigate the effecof the knockdown of the PDGFR-α on the proliferation of human LECin vitro,and to offean experimental basifothe gene therapy of posteriocapsule opacification.MethodHuman LECstrain SRA01/ 04 wacultured in α-MEM containing fetal bovine serum.The cellwere incubated in 6-well platea5 × 104 cells/ well and transfection of ASODN-containing liposome waperformed.The cellwere divided into the blank control group (with blank liposome),PDGFR-α missense oligodeoxynucleotide(MSODN) group (with PDGFR-α MSODN + liposome),0.5 μmol/L PDGFR-α ASODN group (with 0.5 μmol/L PDGFR-α ASODN+liposome) and 1.0 μmol/L PDGFR-α ASODN group (with 1.0 μ mol/L PDGFR-α ASODN+liposome).The morphology of LECwaexamined undean inverse microscope 24 houraftetransfection.The expression of PDGFR-α mRNin the cellwadetected by reverse transcription-PC(RT-PCR).The rate of proliferation (A490) of the cellwaassayed using Mtand the inhibitory rate of PDGFR-α ASODN on proliferation wameasured.The percentage of LECin G1 phase waanalyzed by flow cytometer.ResultThe LECgrew well and exhibited polygonal shape in the blank control group and PDGFR-α MSODN group 24 houraftetransfection.Buin the 0.5 μmol/L and 1.0 μmol/L PDGFR-α ASODN groups,the cellappeared round in shape and the numberof cellwere obviously decreased.The expression of PDGFR-α mRNdetected by RT-Pcdemonstrated highelevel in the blank control group and PDGFR-α MSODN group;however,the PDGFR-α mRNexpression waobviously lowein the 0.5 μmol/L and 1.0 μmol/L PDGFR-α ASODN groups.The A490 value wa0.661 ± 0.036,0.655 ± 0.016,0.529 ± 0.030 and 0.441 ± 0.039 in the blank control group,PDGFR-α MSODN group,0.5 μmol/L PDGFR-α ASODN group and 1.0 μmol/L PDGFR-α ASODN group,respectively,showing significandecline in the 0.5 μmol/L PDGFR-α ASODN group and 1.0 μ mol/L PDGFR-α ASODN group in comparison with the blank control group (F=34.08,P＜0.01).The percentageof LECin G1 phase were (47.73±1.18)％,(49.48±1.09)％,(53.31±1.30)％ and (59.98±0.95) ％ in the blank control group,PDGFR-α MSODN group,0.5 μmol/L PDGFR-α ASODN group and 1.0 μmol/L PDGFR-α ASODN group,showing significandifference among them (F =68.41,P＜0.01),and thain the 0.5 μmol/L PDGFR-α ASODN group o1.0 μmol/L PDGFR-α ASODN group showed significantly increase in comparison with the blank control group (P＜0.05).ConclusionPDGFR-α silencing could inhibithe proliferation of human LECin vitro.

Effect of suppression of platelet-derived growth factor-α receptor expression with antisense oligonucleotide on proliferation and apoptosis of retinal pigment epithelium cell / 中华实验眼科杂志

BackgroundRetinal pigment epithelial(RPE) cells can secrete platelet-derived growth factor (PDGF) and PDGF receptor(PDGFR).Studies have shown that PDGF plays a key role in the formation of proliferative vitreous retinopathy(PVR). ObjectiveThis study was to investigate the proliferation and apoptosis changes of RPE after blockage of the PDGFR-α expression by antisense oligonucleotide ( ASODN ) in vitro. Methods Human RPE cells strain was cultured in low glucose DMEM with 10％ fetal bovine serum.Logarithmic phase cells were collected and incubated in 96-well plate at the density of 5 × 105 cells/hole.PDGFR-α ASODN was transfected into RPE cells at different concentrations for 48 hours.The cells of the blank control group were regularly cultured without any transfection.The changes of PDGFR-α expression were detected by reverse transcription-polymerase chain reaction(RT-PCR),and the proliferation of RPE was detected by MTT as the A490 value.Hoechst 33258 fluorescence staining was used to determine the apoptosis of RPE.Flow cytometry method (FCM) was applied to detect the change of cell cycle and apoptosis rate of RPE cells. ResultsThe A490 values of RPE cells were 1.45±0.12,1.07±0.06,0.65±0.05 in blank control group,1.0 μmol/L Lipo-ASODN group and 2.0 μmol/L Lipo-ASODN group with the significant difference(P=0.00 ),and that of 1.0 μmol/L Lipo-ASODN group and 2.0 μ mol/L Lipo-ASODN group were significantly lower than the blank control group ( P =0.00,0.00).Hoechst 33258 staining showed that the apoptosis cells were obviously more in Lipo-ASODN group compared with blank control group.PDGFR-α ASODN transfection induced an increase of percentage of RPE cells in G0/G1 phase( F =206.70,P =0.00),and the apoptosis rates in 1.0 μmol/L Lipo-ASODN group and 2.0 μmol/L Lipo-ASODN group were significantly enhanced in comparison with blank control group ( 37.8 ± 1.3 vs 10.5 ± 0.1,61.2 ± 1.9 vs 10.5 ± 0.1 ) ( F =1808.90,P =0.00 ).Expression intensity of PDGFR-α mRNA in RPE cells in Lipo-ASODN groups was lower. ConclusionsBlocking the PDGFR-α expression with ASODN technology can suppress proliferation and induce apoptosis of RPE cells.Intensity of PDGFR-α mRNA expression in RPE cells is ASODN dose-dependent.ASODN targeted to PDGFR-α offers an experimental basis of the gene therapy for PVR.

[The efficacy and safety of valproic acid in combination with low dose chemotherapy on intermediate and high-risk myelodysplastic syndrome].

OBJECTIVE: To evaluate the efficacy and adverse effect of valproic acid (VPA) in combination with low dose chemotherapy on intermediate and high-risk myelodysplastic syndrome. METHODS: A total of 41 patients with intermediate (34) and high-risk (7) myelodysplastic syndrome were retrospectively analyzed. Among them, 19 patients received low dose chemotherapy regimen and 22 received low dose chemotherapy plus VPA. Low dose chemotherapy regimen included: homoharringtonine, 1 - 2 mg×m(-2)×d(-1) intravenously, 14 - 28 d; aclarubicin, 5 - 7 mg×m(-2)×d(-1) intravenously, 1 - 8 d, 15 - 23 d; cytarabine 15 mg/m(2) subcutaneously once every 12 h, 14 - 21 d; and subcutaneously use of granulocyte colony-stimulating factor 200 µg·m(-2)×d(-1) when neutrophil deficiency. The outcome and adverse effect were recorded after the treatment. RESULTS: The overall response rate in the low dose chemotherapy regimen group was 47.4% (9/19), 6 patients (31.6%) achieved complete response (CR). The overall response rate in the VPA group was 77.2% (17/22), 9 patients (40.9%) achieved CR. The overall response rate of the low dose chemotherapy in combination with VPA group was significantly higher than that in the low dose chemotherapy group (P < 0.05) while no difference was found in CR rate. The adverse effect of the low dose chemotherapy in combination with VPA regimen was tolerated. CONCLUSION: With acceptable adverse effect, the low dose chemotherapy in combination with VPA regimen is effective for the treatment of intermediate and high-risk myelodysplastic syndrome. Long-term outcome needs further investigation.

The complications of intravitreal triamsinolone acetonide injection in vitrectomy for proliferative diabetic retinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

· AIM: To investigate the complications of intravitreal triamsinolone acetonide (TA) injection in vitrectomy for proliferative diabetic retinopathy (PDR).· METHODS: From February 2005 to January 2007, 18patients (18 eyes) with PDR who were injected with TA in vitrectomy were observed retrospectively after surgery.· RESULTS: During a postoperative follow-up period of 3 to 6 months (mean 4.6 months), some complications including deposit of TA granules on the macular region and surface of the retina (3 eyes), postoperative vitreous hemorrhage (3eyes), elevated intraocular pressure (2 eyes) and pseudohypopyon (1 eye)were observed.· CONCLUSION: The complications after surgery such as deposit of TA granules on the macular region and surface of the retina and pseudohypopyon could be cured without any special treatment. All eyes with elevated intraocular pressure after surgery were controlled by drug. Re-operation may be an effective method for patients with unabsorbable vitreous hemorrhage after vitrectomy.