Objective: To establish enzalutamide-resistant human prostate cancer cell lines and screen out the lncRNA and mRNA expression profiles associated with enzalutamide resistance. METHODS: Human prostate cancer cell lines LNCAP and C4-2B were cultured with 10 μmol/L enzalutamide for 6 months in vitro for the establishment of enzalutamide-resistant subclones LNCAP-ENZA and C4-2B-ENZA. The IC50 value and enzalutamide resistance index of each cell line were examined by MTT assay, the expressions of enzalutamide-related genes FL-AR, AR-V7 and HnRNPA1 were determined by Western blot, and the lncRNA and mRNA differential expressions of C4-2B and C4-2B-ENZA were detected by high-throughout lncRNA microarray. RESULTS: Compared with LNCAP and C4-2B, the IC50 values of enzalutamide-resistant subclones LNCAP-ENZA (60.83 μmol/L) and C4-2B-ENZA (88.32 μmol/L) were increased significantly (P < 0.05) and the enzalutamide-resistance indexes of the LNCAP-ENZA and C4-2B-ENZA cells were 4.94 and 4.67, respectively. The expressions of AR-V7 and HnRNPA1 were markedly up-regulated in the LNCAP-ENZA and C4-2B-ENZA cells as compared with those in the LNCAP and C4-2B cells, but that of FL-AR showed no significant change. A total of 1 440 lncRNAs and 1 236 mRNAs were identified as differentially expressed in the C4-2B-ENZA cells. CONCLUSIONS Enzalutamide -resistant human prostate cancer cell subclones LNCAP-ENZA and C4-2B-ENZA were successfully established and enzalutamide resistance-associated lncRNA and mRNA were identified, which may provide some molecular evidence for the management of enzalutamide-resistant human prostate cancer.
Cell Line, Tumor ; drug effects ; Drug Resistance, Neoplasm ; Humans ; Male ; Phenylthiohydantoin ; analogs & derivatives ; pharmacology ; Prostatic Neoplasms ; drug therapy ; genetics ; pathology ; RNA, Long Noncoding ; metabolism ; RNA, Messenger ; metabolism ; RNA, Neoplasm ; metabolism ; Receptors, Androgen

OBJECTIVETo investigate the role of Mcl-1 gene in resistance of all-trans retinoic acid (ATRA) of leukemia cells.

METHODSLong-term, intermittent and repetitive exposure of HL-60 cells to ATRA was used to establish a multidrug-resistance cell line (HL-60/ATRA). HL-60/ATRA cells were transfected with Mcl-1 small interference RNA (siRNA) by Lipofectamine 2000. Western blot was used to detect the expression of Mcl-1. The proliferation, apoptosis and differentiation were evaluated by MTT assay, in situ nick end-labeling (TUNEL) and NBT assay, respectively.

RESULTSThe HL-60/ATRA could keep its undifferentiated and proliferative status to a high concentration of ATRA (100 nmol/L) with highly expressed Mcl-1 protein (relative grey scale 0.624 +/- 0.127). Mcl-1 gene knockdown by siRNA (relative grey scale 0.267 +/- 0.086) could reverse the resistance of ATRA of HL-60/ATRA by inhibiting proliferation, and inducing differentiation and apoptosis [apoptosis rate (18.5 +/- 4.5)%].

CONCLUSIONMcl-1 gene might be involved in ATRA resistance in HL-60 cells and inhibiting its expression could be a new approach to ATRA resistance reversion.

Apoptosis ; drug effects ; genetics ; Cell Differentiation ; drug effects ; genetics ; Cell Proliferation ; drug effects ; Drug Resistance, Neoplasm ; genetics ; HL-60 Cells ; drug effects ; metabolism ; Humans ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; RNA, Small Interfering ; Tretinoin ; pharmacology

OBJECTIVETo investigate the effect of small interference RNA (siRNA) on mdr1 and P-glyco-protein (P-gp) expression of multi-drug resistance (MDR) human leukemia cell line K562/A02.

METHODSThree si RNAs (si-mdr1-1, si-mdr1-2, si-mdr1-3) which were specifically targeted mdr1 gene were synthesized and transfected into K562/A02 cells. Expression of mdr1 mRNA was assayed by RT-PCR. P-gp expression and intracellular daunorubicin (DNR) concentration were determined by flow cytometry. 50% inhibition concentration (IC(50)) of doxorubicin (ADM) on K562/A02 was determined by MTT method.

RESULTSTreatment of K562/A02 cell with the 3 kinds of siRNAs resulted in a reversal of MDR of a different extent. The third siRNA was more effective in the suppression of mdr1 with a significant reduction of (58.0 +/- 1.54)% of the mdr1 mRNA expression. Positive expression rate of p170 decreased from (76.0 +/- 1.0)% to (19.6 +/- 1.9)%, and the relative efficiency of K562/A02 to ADM was 70.4%. The intracellular accumulation of DNR increased after siRNA treatment.

CONCLUSIONThe siRNA could effectively restore the sensitivity of K562/A02 cells to conventional chemotherapeutic agents.

Base Sequence ; Daunorubicin ; pharmacokinetics ; Drug Resistance, Neoplasm ; Genes, MDR ; physiology ; Humans ; K562 Cells ; drug effects ; Molecular Sequence Data ; RNA, Messenger ; analysis ; RNA, Small Interfering ; pharmacology

To study the mechanisms involved in the inhibition of chronic myeloid leukemic cells (K562) proliferation induced by arsenic trioxide (As2O3) and to explore the potential role of Survivin, an inhibitor of apoptosis protein, in the regulation of As2O3 induced cell apoptosis, K562 cells were cultured with As2O3 of different concentrations. Cells were collected for proliferation analysis by MTT assay. Cell cycle distribution and cell apoptosis were analyzed by flow cytometry. Expression of Survivin protein and mRNA were detected by flow cytometry and RT-PCR, respectively. Our results showed that As2O3(2-10 micromol/L) inhibited K562 cells growth effectively, but it did not induce cells apoptosis significantly. The percentage of K562 cells at G2/M phase increased in proportion to As2O3 concentrations, and the expression of Survivin mRNA and content of Survivin protein was up-regulated accordingly. It is concluded that As2O3 inhibited K562 cells growth by inducing cell cycle arrest mainly at G2/M phase. Over-expression of Survivin gene and protein might be one of the possible mechanisms contributing to K562 cells' resistance to As2O3-induced apoptosis.
Antigens, Neoplasm ; biosynthesis ; genetics ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Cell Cycle ; drug effects ; Cell Division ; drug effects ; Humans ; Inhibitor of Apoptosis Proteins ; K562 Cells ; Microtubule-Associated Proteins ; biosynthesis ; genetics ; Neoplasm Proteins ; Oxides ; pharmacology ; RNA, Messenger ; biosynthesis ; genetics

OBJECTIVETo investigate the effects of survivin antisense oligonucleotide (ODN) on cell proliferation and apoptosis of HL-60 cells.

METHODSSynthetic ODN was completely phosphorothioate-modified. Cationic lipid-mediated antisense ODN was transferred into HL-60 cells. The expression of survivin mRNA and protein was detected by RT-PCR and Western Blot. The incorporation of MTT was used as the measurement of HL-60 proliferation. The cell-cycle and apoptosis were analyzed by flow cytometry.

RESULTSHL-60 cells spontaneously expressed survivin mRNA and protein. Both mRNA and protein expression of survivin decreased significantly in the antisense ODN transfected cells in comparison to that in the original cells and cells transfected with sense ODN. Survivin antisense ODN significantly inhibited cell proliferation and induced apoptosis in a dose-dependent manner. The cell-cycle in the antisense ODN-transfected cells stopped at the G2/M phase.

CONCLUSIONSAntisense ODN targeting at survivin mRNA can inhibit HL-60 cell proliferation and induce G2/M stop and apoptosis.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; HL-60 Cells ; drug effects ; Humans ; Inhibitor of Apoptosis Proteins ; Microtubule-Associated Proteins ; antagonists & inhibitors ; genetics ; Neoplasm Proteins ; antagonists & inhibitors ; genetics ; Oligonucleotides, Antisense ; pharmacology ; RNA, Messenger ; analysis

OBJECTIVETo reverse the multidrug resistant (MDR) phenotype of human breast carcinoma cells by small hairpin RNA (shRNA) technique targeting hypoxia-inducible factor (HIF)-1alpha gene.

METHODSSmall hairpin RNA (shRNA) eukaryotic expression vector targeting HIF-1alpha gene, named pSilencer-HIF, was constructed and transfected into MCF-7/ADR human breast cancer cells by liposome technique. Tumor cell livability (TCL) and Rhodamine 123 efflux assay were used to monitor the biological changes of the transfected cells. The mRNA and protein expression of HIF-1alpha and mdr-1 were investigated by RT-PCR and Western blot.

RESULTSThe successful construction of pSilencer-HIF plasmid was confirmed by DNA sequencing. HIF-1alpha mRNA and protein levels were significantly decreased in MCF-7/ADR cells after the transfection and there was a direct correlation between HIF-1alpha and mdr-1 expression. By comparing the cells transfected with control vector and the MCF-7/ADR cells transfected with pSilencer-HIF, a reduced TCL from 76% to 43%, and an increased Rhodamine 123 fluorescence intensity from 22.0% to 86.6% were observed.

CONCLUSIONSpSilencer-HIF-1alpha has been successfully constructed. The inhibition of HIF-1alpha expression through shRNA technique can significantly reverse the multidrug resistance phenotype of MCF-7/ADR cells.

Breast Neoplasms ; pathology ; Cell Line, Tumor ; Drug Resistance, Multiple ; drug effects ; physiology ; Drug Resistance, Neoplasm ; drug effects ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; antagonists & inhibitors ; RNA Interference ; RNA, Small Interfering ; pharmacology

OBJECTIVETo transfect a short hairpin RNA (shRNA) against survivin gene into human T lymphoblastic leukemia cell line Jurkat, and to explore the effects on apoptosis and proliferation of transfected cells.

METHODSThe survivin-shRNA expression vector were constructed and transfected into Jurkat cells. Expression of survivin mRNA and protein were assessed by RT-PCR and Western blot analysis respectively. Apoptosis index of transfected Jurkat cells was quantified by flow cytometry. The potential of cell proliferation was described by cell growth curves.

RESULTSIn survivin-shRNA transfected Jurkat cells, survivin mRNA levels were significantly reduced by 66.67% ( transient transfection) and 60.69% ( stable transfection) respectively, compared with that in control-shRNA treated group and PBS treated group (P < 0.05); and the levels of survivin protein were significantly reduced by 63.41% (transient transfection) and 60.18% (stable transfection), compared with that in the two control groups (P < 0.05). Apoptosis index was significantly increased during both transient and stable transfection, respectively [(22. 41 +/- 2.83)% and (20.73 +/- 2.56)% (P < 0.05)]. Survivin-shRNA also inhibited the proliferation of Jurkat cells.

CONCLUSIONSVector-based survivin-shRNA can effectively reduce the expression of survivin gene, induce apoptosis

Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Gene Expression ; Gene Silencing ; Humans ; Inhibitor of Apoptosis Proteins ; Jurkat Cells ; Microtubule-Associated Proteins ; biosynthesis ; genetics ; Neoplasm Proteins ; biosynthesis ; genetics ; RNA Interference ; RNA, Messenger ; biosynthesis ; RNA, Small Interfering ; pharmacology

OBJECTIVETo investigate the effects of lentivirus-mediated RNA interference (RNAi) targeting a proliferation-inducing ligand (APRIL) on the chemosensitivity to 5-FU of colorectal cancer cell line LoVo.

METHODSThe lentiviral vector siRNA-APRIL was constructed and verified by PCR and DNA sequencing. LoVo cells were transfected with siRNA-APRIL plasmid, non-targeting siRNA plasmid, or empty plasmid. Forty-eight hours after the transfection, the cells were examined for APRIL expression using Western blot. Seventy-two hours after treatment with 10 µg/ml 5-FU, flow cytometry was used to detect the cell apoptosis and cell cycle changes. The cell growth inhibition rate following 5-FU exposure was detected by MTT assay.

RESULTSPCR analysis and DNA sequencing demonstrated that the RNAi sequence targeting APRIL gene was successfully inserted into the lentiviral vector. siRNA-APRIL transfection resulted in obviously reduced expression of APRIL in LoVo cells. After 5-FU exposure, the apoptosis rate of siRNA-APRIL-transfected cells were increased to (21.12∓3.35)%, significantly higher than that in cells transfected with the non-targeting plasmid or the empty plasmid [(13.06∓1.92)% and (12.28∓1.79)%, respectively, P<0.01]; the cell number in G0/G1 phase increased while that in G2/M phase decreased in siRNA-APRIL-transfected cells. The growth inhibition rate in siRNA-APRIL group was (59.67∓5.03)%, significantly higher than that in the other two groups [(42.33∓4.16)% and (39.67∓4.73)%, respectively, P<0.01].

CONCLUSIONLentivirus-mediated RNAi targeting APRIL can effectively suppress the expression of APRIL in LoVo cells and enhance the chemosensitivity of the cells to 5-FU.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colorectal Neoplasms ; drug therapy ; metabolism ; pathology ; Drug Resistance, Neoplasm ; Fluorouracil ; pharmacology ; Humans ; Lentivirus ; genetics ; RNA Interference ; Tumor Necrosis Factor Ligand Superfamily Member 13 ; genetics ; metabolism

This study was purposed to investigate the effects of angelicasinensis (Oliv) Diel compound injection, vauqueline, ephedrine and strychnine on human erythroleukemia multidrug resistance (MDR) K562/A02 cell line Mdr1 gene and p-glycoprotein. The MTT and trypan blue methods were used to analyze the cytotoxic effect of above-mentioned traditional Chinese drug; the expressions of K562/A02 cells Mdr1 gene and p-glycoprotein were detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot respectively. The results showed that after K562/A02 cell were treated with angelicasinensis (Oliv) diels compound injection, vauqueline and ephedrine, mRNA transcription of Mdr1 gene was reduced significantly (p < 0.01); the expression of P-gp also decreased (p < 0.01). The expression level P-gp in group treated with vauqueline was the lowest, but the Mdr1 mRNA level and expression of P-gp of K562/A02 cells treated with strychnine did not obviously changed. It is concluded that angelicasinensis (Oliv) diels compound injection, vauqueline, ephedrine can partly reverse the multidrug resistance of K562/A02 cells, the down-regulation of Mdr1 gene causing decrease of p-glycoprotein expression may be one of the MDR reversal mechanisms in K562/A02 cells.
ATP-Binding Cassette, Sub-Family B, Member 1 ; genetics ; metabolism ; Down-Regulation ; drug effects ; Doxorubicin ; pharmacology ; Drug Resistance, Multiple ; drug effects ; Drug Resistance, Neoplasm ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Humans ; K562 Cells ; RNA, Messenger ; genetics ; metabolism

Ribosomal protein S27a (RPS27a) can perform extra-ribosomal functions besides imparting a role in ribosome biogenesis and post-translational modifications of proteins. The RPS27a gene has been reported to be over-expressed in breast fibroadenomas, colorectal and renal cancers, advanced-phase chronic myeloid leukemia (CML) and acute leukemia (AL) patients. This study was purposed to explore the function of RPS27a in CML-erythroleukemia cell line K562 cells. RPS27a was silenced by short hairpin RNA (shRNA) in K562 cells. Furthermore, the proliferation changes of K562 cells was detected by MTT method after silencing the RPS27a with suberoylanilide hydroxamic acid (SAHA), then the IC50 of K562-sh1/sh2 and K562-scr cells to SAHA was measured. The results indicated that compared with K562-scr cells, the IC50 of K562-sh1/sh2 to SAHA at 24 h and 48 h decreased (P < 0.01); RPS27a silence significantly increased the percentage of apoptotic K562-sh1/sh2 cells after incubation with 1 µmol/L, 2 µmol/L and 5 µmol/L SAHA for 24 h and 48 h as compared with that of K562-scr cells (P < 0.01). K562-sh1, K562-sh2 and K562-scr cells after incubation with or without 2 µmol/L SAHA for 48 h presented apoptosis features: i. e. chromatin condensation, nucleic fragmentation and apoptotic body formation. It is concluded that RPS27a can inhibit the apoptosis of K562 cells and RPS27a silence can potentiate sensitivity of K562 cells to SAHA.
Apoptosis ; drug effects ; Drug Resistance, Neoplasm ; Drug Screening Assays, Antitumor ; Gene Silencing ; Humans ; Hydroxamic Acids ; pharmacology ; K562 Cells ; RNA, Small Interfering ; genetics ; Ribosomal Proteins ; genetics ; metabolism