Suppressor of Variegation 3–9 Homolog 2 (SUV39H2) methylates the lysine 9 residue of histone H3 and induces heterochromatin formation, resulting in transcriptional repression or silencing of target genes. SUV39H1 and SUV39H2 have a role in embryonic development, and SUV39H1 was shown to suppress cell cycle progression associated with Rb. However, the function of human SUV39H2 has not been extensively studied. We observed that forced expression of SUV39H2 decreased cell proliferation by inducing G1 cell cycle arrest. In addition, SUV39H2 was degraded through the ubiquitin-proteasomal pathway. Using yeast two-hybrid screening to address the degradation mechanism and function of SUV39H2, we identified translationally controlled tumor protein (TCTP) as an SUV39H2-interacting molecule. Mapping of the interacting regions indicated that the N-terminal 60 amino acids (aa) of full-length SUV39H2 and the C-terminus of TCTP (120–172 aa) were critical for binding. The interaction of SUV39H2 and TCTP was further confirmed by co-immunoprecipitation and immunofluorescence staining for colocalization. Moreover, depletion of TCTP by RNAi led to up-regulation of SUV39H2 protein, while TCTP overexpression reduced SUV39H2 protein level. The half-life of SUV39H2 protein was significantly extended upon TCTP depletion. These results clearly indicate that TCTP negatively regulates the expression of SUV39H2 post-translationally. Furthermore, SUV39H2 induced apoptotic cell death in TCTP-knockdown cells. Taken together, we identified SUV39H2, as a novel target protein of TCTP and demonstrated that SUV39H2 regulates cell proliferation of lung cancer cells.
Amino Acids ; Apoptosis ; Carrier Proteins ; Cell Cycle ; Cell Death ; Cell Proliferation ; Embryonic Development ; Female ; Fluorescent Antibody Technique ; G1 Phase Cell Cycle Checkpoints ; Half-Life ; Heterochromatin ; Histones ; Humans ; Immunoprecipitation ; Lung Neoplasms ; Lysine ; Mass Screening ; Pregnancy ; Repression, Psychology ; RNA Interference ; Up-Regulation ; Yeasts

PURPOSE: This study investigated the role of natriuretic peptide receptor 2 (NPR2) on cell proliferation and testosterone secretion in mouse Leydig cells. MATERIALS AND METHODS: Mouse testis of different postnatal stages was isolated to detect the expression C-type natriuretic peptide (CNP) and its receptor NPR2 by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Leydig cells isolated from mouse testis were cultured and treated with shNPR2 lentiviruses or CNP. And then the cyclic guanosine monophosphate production, testosterone secretion, cell proliferation, cell cycle and cell apoptosis in mouse Leydig cells were analyzed by ELISA, RT-qPCR, Cell Counting Kit-8, and flow cytometry. Moreover, the expression of NPR2, cell cycle, apoptosis proliferation and cell cycle related gene were detected by RT-qPCR and Western blot. RESULTS: Knockdown of NPR2 by RNAi resulted in S phase cell cycle arrest, cell apoptosis, and decreased testosterone secretion in mouse Leydig cells. CONCLUSIONS: Our study provides more evidences to better understand the function of CNP/NPR2 pathway in male reproduction, which may help us to treat male infertility.
Animals ; Apoptosis ; Blotting, Western ; Cell Count ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Proliferation ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Germ Cells ; Guanosine Monophosphate ; Humans ; Infertility, Male ; Lentivirus ; Leydig Cells ; Male ; Mice ; Natriuretic Peptide, C-Type ; Polymerase Chain Reaction ; Receptors, Peptide ; Reproduction ; Reverse Transcription ; RNA Interference ; S Phase ; Testicular Diseases ; Testis ; Testosterone

Talaromyces marneffei is the only dimorphic species in its genus and causes a fatal systemic mycosis named talaromycosis. Our previous study indicated that knockdown of AcuD gene (encodes isocitrate lyase of glyoxylate bypass) of T. marneffei by RNA interference approach attenuated the virulence of T. marneffei, while the virulence of the AcuD knockout strains was not studied. In this study, T. marneffei-zebrafish infection model was successfully established through hindbrain microinjection with different amounts of T. marneffei yeast cells. After co-incubated at 28°C, the increasing T. marneffei inoculum doses result in greater larval mortality; and hyphae generation might be one virulence factor involved in T. marneffei-zebrafish infection. Moreover, the results demonstrated that the virulence of the ΔAcuD was significantly attenuated in this Zebrafish infection model.
Gene Knockout Techniques ; Hyphae ; Isocitrate Lyase ; Microinjections ; Mortality ; Rhombencephalon ; RNA Interference ; Talaromyces ; Virulence ; Yeasts ; Zebrafish

OBJECTIVE: This study aimed to explore the influence of Rce1 on invasion and migration of tongue squamous cell carcinoma cells by silencing the Rce1 gene with RNA interference. METHODS: The tongue squamous cell carcinoma Cal-27 and SCC-4 cells were cultured in vitro. The small interfering RNA (siRNA) of the Rce1 gene was designed, and the Rcel gene expression was silenced vialiposome transfection. According to the siRNA transfected by liposome, the experimental group was divided into three groups, namely, Rce1-siRNA-1, Rce1-siRNA-2, and Rce1-siRNA-3 groups. Negative control group was transfected by siCON, and the blank control group was untransfected by siRNA. The Rce1, RhoA, and K-Ras gene expression levels in each group were analyzed by real-time quantitative polymerase chain reaction. The Rce1, RhoA, K-Ras, MMP-2, and MMP-9 protein expression levels were analyzed by Western blot. The invasiveness of tongue cancer cell Cal-27 and SCC-4 were determined by Transwell invasion assay, and cell migration assay was performed by cell scratch assay. RESULTS: Real-time quantitative polymerase chain reaction and Western blot results showed that compared with the negative and blank control groups, the Rce1 gene and protein expression levels in three experimental groups decreased (P<0.05). The RhoA, K-Ras gene and protein expression levels were insignificantly different among groups (P>0.05). Meanwhile, the MMP-2 and MMP-9 expression levels decreased (P<0.05). Transwell invasion assay results showed that the total number of cells in the PET film of the experimental groups was significantly decreased compared with the control group (P<0.05). The cell scratch test showed that the cell closure time of the scratch in the interference group was significantly longer than those in the control and blank groups (P<0.05). CONCLUSIONS Silencing Rce1 in vitro can effectively downregulate its expression in tongue squamous cell carcinoma cells Cal-27 and SCC-4 and reduce the migration and invasion abilities of these cells.
Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Endopeptidases ; metabolism ; Humans ; Neoplasm Invasiveness ; RNA Interference ; RNA, Small Interfering ; Tongue Neoplasms ; metabolism ; therapy ; Transfection

OBJECTIVE: To investigate the effect of steadily down-regulating the expression of calreticulin (CALR) on the invasion of natural killer/T-cell lymphoma SNK6 cells, and explore its possible mechanism. METHODS: The sequences of specific short hairpin RNA (shRNA) targeting on human CALR were designed, and were inserted into pLKO.1-puro lentivirus vector, and the reconbinant lentivirus vector was obtained; the lentivirus particles were backed by three-plasmid system and transfected into SNK6 cells, the SNK6 cells stably down-regulating the CALR expression were sercened by puromytain, the CALR-silencing effect was verified by real-time PCR and Western blot. CCK-8 assay was used to evaluate the cell viability, The transwell invasion assays was used to analyse invasion of SNK6 cells. The mRNA expression of Calreticulin, MMP2, MMP9 and VEGF was determined by real time PCR, the protein expression of Calreticulin and GAPDH was analyzed by Western blot. RESULTS: The recombinant lentiviral vector pLKO.1-puro-shCALR was successfully constructed, packed into the lentivirus, then the SNK6 cells stably down-regulating Calreticulin expression was obtained. When Calreticulin was down-rengulated in SNK6 cells, the proliferation rate was reduced and the invasion ability was decreased; the mRNA levels of VEGF and MMP-2/9 also were reduced. CONCLUSION The stable down-regnlation of CALR expression in SNK6 cells can attenuate the imvasiveness of SNK6 cells, which maybe related with transcriptional decrease of MMP2, MMP9 and VEGF.
Calreticulin ; genetics ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Down-Regulation ; Genetic Vectors ; Humans ; Lentivirus ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase 9 ; RNA Interference ; RNA, Small Interfering ; Transfection ; Vascular Endothelial Growth Factor A

OBJECTIVE: To analyze the effect of down-regulating the CD59 gene expression by RNAi lentivirus as vector on Jurkat cell line of acute T-lineage leukemia. METHODS: The expression of CD59 in Jurkat cell line of acute T-line leukemia was induced to decrease by RNAi lentivirus as vector. The transfection of RNA lentivirus and the localization of CD59 molecule were analyzed by laser confocal technique. The relative expression of CD59 gene in blank control, negative control and RNAi lentivirus transfected group was detected by real-time fluorescence quantitative PCR, and the enzyme-linked immunosorbent assay was used to detect the expression of TNF-β and IL-3 in supernatants of cultured cells in 3 groups. The expression levels of apoptosis-related molecules including Caspase-3, Survivin, BCL-2 and BCL-2-associated X protein (BAX) were measured by Western blot. RESULTS: The transfection efficiency for Jurkat cells was higher than 90%. CD59 was mainly located on the cell membrane. Compared with the blank control group and the negative control group, the expression level of CD59 mRNA and protein in the RNAi lentivirus transfected group significantly decreased (P<0.05). Compared with the blank control group and the negative control group, the expression of TNF-β and IL-3 in the RNAi lentivirus transfected group were significantly higher and lower (P<0.05) respectively. The expression levels of Survivin and BCL-2 in the RNAi lentivirus transfected group were significantly lower than those in the blank control group and the negative control group, while the expression levels of Caspase-3 and BAX in the RNAi lentivirus transfected group were significantly higher than those in the blank control group and the negative control group (P< 0.05). CONCLUSION The down-regulation of CD59 gene expression induced by RNAi lenti-virus can decrease the expression of proliferation and differentiation-promoting molecule such as IL-3 and increase the expression of TNF-related factor in Jurkat cell line of acute T-lineage leukemia, which also can increase the expression of apoptosis-related proteins such as Caspase-3 and BAX, and decrease the expression of anti-apoptosis-related proteins such as Survivin and BCL-2.
Apoptosis ; CD59 Antigens ; Cell Lineage ; Cell Proliferation ; Down-Regulation ; Humans ; Jurkat Cells ; Lentivirus ; Leukemia ; RNA Interference ; RNA, Small Interfering ; Transfection

Melanin is a pigment produced from tyrosine in melanocytes. Although melanin has a protective role against UVB radiation-induced damage, it is also associated with the development of melanoma and darker skin tone. Tyrosinase is a key enzyme in melanin synthesis, which regulates the rate-limiting step during conversion of tyrosine into DOPA and dopaquinone. To develop effective RNA interference therapeutics, we designed a melanin siRNA pool by applying multiple prediction programs to reduce human tyrosinase levels. First, 272 siRNAs passed the target accessibility evaluation using the RNAxs program. Then we selected 34 siRNA sequences with ΔG ≥−34.6 kcal/mol, i-Score value ≥65, and siRNA scales score ≤30. siRNAs were designed as 19-bp RNA duplexes with an asymmetric 3′ overhang at the 3′ end of the antisense strand. We tested if these siRNAs effectively reduced tyrosinase gene expression using qRT-PCR and found that 17 siRNA sequences were more effective than commercially available siRNA. Three siRNAs further tested showed an effective visual color change in MNT-1 human cells without cytotoxic effects, indicating these sequences are anti-melanogenic. Our study revealed that human tyrosinase siRNAs could be efficiently designed using multiple prediction algorithms.
Dihydroxyphenylalanine ; Gene Expression ; Humans ; Melanins ; Melanocytes ; Melanoma ; Monophenol Monooxygenase* ; RNA ; RNA Interference ; RNA, Small Interfering* ; Skin Pigmentation ; Tyrosine ; Weights and Measures

PURPOSE: Lapatinib is a candidate drug for treatment of trastuzumab-resistant, human epidermal growth factor receptor 2 (HER2)–positive gastric cancer (GC). Unfortunately, lapatinib resistance renders this drug ineffective. The present study investigated the implication of forkhead box O1 (FOXO1) signaling in the acquired lapatinib resistance in HER2-positive GC cells. MATERIALS AND METHODS: Lapatinib-resistant GC cell lines (SNU-216 LR2-8) were generated in vitro by chronic exposure of lapatinib-sensitive, HER2-positive SNU-216 cells to lapatinib. SNU-216 LR cells with FOXO1 overexpression were generated by stable transfection of a constitutively active FOXO1 mutant (FOXO1A3). HER2 and MET in SNU-216 LR cells were downregulated using RNA interference. The sensitivity of GC cells to lapatinib and/or cisplatin was determined by crystal violet assay. In addition, Western blot analysis, luciferase reporter assay and reverse transcription–polymerase chain reaction were performed. RESULTS: SNU-216 LR cells showed upregulations of HER2 and MET, but downregulation of FOXO1 compared to parental SNU-216 cells. FOXO1 overexpression in SNU-216 LR cells significantly suppressed resistance to lapatinib and/or cisplatin. In addition, FOXO1 negatively controlled HER2 and MET at the transcriptional level and was negatively controlled by these molecules at the post-transcriptional level. A positive crosstalk was shown between HER2 and MET, each of which increased resistance to lapatinib and/or cisplatin. CONCLUSION: FOXO1 serves as an important linker between HER2 and MET signaling pathways through negative crosstalks and is a key regulator of the acquired lapatinib resistance in HER2-positive GC cells. These findings provide a rationale for establishing a novel treatment strategy to overcome lapatinib resistance in a subtype of GC patients.
Blotting, Western ; Cell Line ; Cisplatin ; Down-Regulation ; Drug Resistance ; Gentian Violet ; Humans ; In Vitro Techniques ; Luciferases ; Parents ; Receptor, Epidermal Growth Factor ; Receptor, ErbB-2 ; RNA Interference ; Stomach Neoplasms ; Transfection ; Up-Regulation

PURPOSE: Epigenetic modifications, such as histone acetylation/deacetylation and DNA methylation, play a crucial role in the pathogenesis of inflammatory disorders and fibrotic diseases. The aim of this study was to study the differential gene expression of histone deacetylases (HDACs) in fibroblasts isolated from plaque tissue of Peyronie's disease (PD) or normal tunica albuginea (TA) and to examine the anti-fibrotic effect of small interfering RNA (siRNA)-mediated silencing of HDAC7 in fibroblasts derived from human PD plaque. MATERIALS AND METHODS: For differential gene expression study, we performed reverse-transcriptase polymerase chain reaction for HDAC isoforms (1–11) in fibroblasts isolated from PD plaque or normal TA. Fibroblasts isolated from PD plaque were pretreated with HDAC7 siRNA (100 pmol) and then stimulated with transforming growth factor-β1 (TGF-β1, 10 ng/mL). Protein was extracted from treated fibroblasts for Western blotting. We also performed immunocytochemistry to detect the expression of extracellular matrix proteins and to examine the effect of HDAC2 siRNA on the TGF-β1-induced nuclear translocation of Smad2/3 and myofibroblastic differentiation. RESULTS: The mRNA expression of HDAC2, 3, 4, 5, 7, 8, 10, and 11 was higher in fibroblasts isolated from PD plaque than in fibroblasts isolated from normal TA tissue. Knockdown of HDAC7 in PD fibroblasts inhibited TGF-β1-induced nuclear shuttle of Smad2 and Smad3, transdifferentiation of fibroblasts into myofibroblasts, and abrogated TGF-β1-induced production of extracellular matrix protein. CONCLUSIONS: These findings suggest that specific inhibition of HDAC7 with RNA interference may represent a promising epigenetic therapy for PD.
Blotting, Western ; DNA Methylation ; Epigenomics ; Extracellular Matrix ; Extracellular Matrix Proteins ; Fibroblasts* ; Fibrosis ; Gene Expression ; Histone Deacetylases* ; Histones* ; Humans ; Immunohistochemistry ; Male ; Myofibroblasts ; Penile Induration ; Polymerase Chain Reaction ; Protein Isoforms ; RNA Interference ; RNA, Messenger ; RNA, Small Interfering ; Transforming Growth Factors

PURPOSE: This study aimed to explore the functions and mechanisms of C-C motif chemokine receptor 6 (CCR6), a gene associated with progression and metastasis of colorectal cancer (CRC), in radiosensitivity of rectal cancer (RC). MATERIALS AND METHODS: RNA sequencing and immunohistochemical analysis on CCR6 expression were performed in pretreatment tissues of RC patients exhibiting different therapeutic effects of radiotherapy. Colonogenic survival assay was conducted in different CRC cell lines to assess their radiosensitivity. And the impact of CCR6 expression on radiosensitivity was validated through RNA interference. The DNA damage repair (DDR) abilities of cell lines with different CCR6 expression were evaluated through immunofluorescence-based γH2AX quantification. RESULTS: The CCR6 mRNA level was higher in patients without pathologic complete remission (pCR) than in those with pCR (fold changed, 2.11; p=0.004). High-level expression of CCR6 protein was more common in the bad responders than in the good responders (76.3% vs. 37.5%, p < 0.001). The CRC cell lines with higher CCR6 expression (LoVo and sw480) appeared to be more radioresistant, compared with the sw620 cell line which had lower CCR6 expression. CCR6 knockdown made the LoVo cells more sensitive to ionizing radiation (sensitization enhancement ratio, 1.738; p < 0.001), and decreased their DDR efficiency. CONCLUSION: CCR6 might affect the RC radiosensitivity through DDR process. These findings supported CCR6 as a predicting biomarker of radiosensitivity and a potential target of radiosensitization for RC patients.
Cell Line ; Colorectal Neoplasms ; DNA Damage ; Genes, vif ; Humans ; Neoplasm Metastasis ; Polymerase Chain Reaction ; Radiation Tolerance* ; Radiation, Ionizing ; Radiotherapy ; Rectal Neoplasms* ; RNA Interference ; RNA, Messenger ; Sequence Analysis, RNA ; Therapeutic Uses