Construction of Genetic Map and QTL Mapping for Seed Size and Quality Traits in Soybean (Glycine max L.).

Soybean (Glycine max L.) is the main source of vegetable protein and edible oil for humans, with an average content of about 40% crude protein and 20% crude fat. Soybean yield and quality traits are mostly quantitative traits controlled by multiple genes. The quantitative trait loci (QTL) mapping for yield and quality traits, as well as for the identification of mining-related candidate genes, is of great significance for the molecular breeding and understanding the genetic mechanism. In this study, 186 individual plants of the F2 generation derived from crosses between Changjiangchun 2 and Yushuxian 2 were selected as the mapping population to construct a molecular genetic linkage map. A genetic map containing 445 SSR markers with an average distance of 5.3 cM and a total length of 2375.6 cM was obtained. Based on constructed genetic map, 11 traits including hundred-seed weight (HSW), seed length (SL), seed width (SW), seed length-to-width ratio (SLW), oil content (OIL), protein content (PRO), oleic acid (OA), linoleic acid (LA), linolenic acid (LNA), palmitic acid (PA), stearic acid (SA) of yield and quality were detected by the multiple- d size traits and 113 QTLs related to quality were detected by the multiple QTL model (MQM) mapping method across generations F2, F2:3, F2:4, and F2:5. A total of 71 QTLs related to seed size traits and 113 QTLs related to quality traits were obtained in four generations. With those QTLs, 19 clusters for seed size traits and 20 QTL clusters for quality traits were summarized. Two promising clusters, one related to seed size traits and the other to quality traits, have been identified. The cluster associated with seed size traits spans from position 27876712 to 29009783 on Chromosome 16, while the cluster linked to quality traits spans from position 12575403 to 13875138 on Chromosome 6. Within these intervals, a reference genome of William82 was used for gene searching. A total of 36 candidate genes that may be involved in the regulation of soybean seed size and quality were screened by gene functional annotation and GO enrichment analysis. The results will lay the theoretical and technical foundation for molecularly assisted breeding in soybean.

M6A modification regulates tumor suppressor DIRAS1 expression in cervical cancer cells.

DIRAS family GTPase 1 (DIRAS1) has been reported as a potential tumor suppressor in other human cancer. However, its expression pattern and role in cervical cancer remain unknown. Knockdown of DIRAS1 significantly promoted the proliferation, growth, migration, and invasion of C33A and SiHa cells cultured in vitro. Overexpression of DIRAS1 significantly inhibited the viability and motility of C33A and SiHa cells. Compared with normal cervical tissues, DIRAS1 mRNA levels were significantly lower in cervical cancer tissues. DIRAS1 protein expression was also significantly reduced in cervical cancer tissues compared with para-cancerous tissues. In addition, DIRAS1 expression level in tumor tissues was significantly negatively correlated with the pathological grades of cervical cancer patients. DNA methylation inhibitor (5-Azacytidine) and histone deacetylation inhibitor (SAHA) resulted in a significant increase in DIRAS1 mRNA levels in C33A and SiHa cells, but did not affect DIRAS1 protein levels. FTO inhibitor (FB23-2) significantly down-regulated intracellular DIRAS1 mRNA levels, but significantly up-regulated DIRAS1 protein levels. Moreover, the down-regulation of METTL3 and METTL14 expression significantly inhibited DIRAS1 protein expression, whereas the down-regulation of FTO and ALKBH5 expression significantly increased DIRAS1 protein expression. In conclusion, DIRAS1 exerts a significant anti-oncogenic function and its expression is significantly downregulated in cervical cancer cells. The m6A modification may be a key mechanism to regulate DIRAS1 mRNA stability and protein translation efficiency in cervical cancer.

Construction of a genetic map and QTL mapping of seed size traits in soybean.

Soybean seed size and seed shape traits are closely related to plant yield and appearance quality. In this study, 186 individual plants of the F2 generation derived from crosses between Changjiang Chun 2 and JiYu 166 were selected as the mapping population to construct a molecular genetic linkage map, and the phenotypic data of hundred-grain weight, seed length, seed width, and seed length-to-width ratio of soybean under three generations of F2 single plants and F2:3 and F2:4 lines were combined to detect the QTL (quantitative trait loci) for the corresponding traits by ICIM mapping. A soybean genetic map containing 455 markers with an average distance of 6.15 cM and a total length of 2799.2 cM was obtained. Forty-nine QTLs related to the hundred-grain weight, seed length, seed width, and seed length-to-width ratio of soybean were obtained under three environmental conditions. A total of 10 QTLs were detected in more than two environments with a phenotypic variation of over 10%. Twelve QTL clusters were identified on chromosomes 1, 2, 5, 6, 8, 13, 18, and 19, with the majority of the overlapping intervals for hundred-grain weight and seed width. These results will lay the theoretical and technical foundation for molecularly assisted breeding in soybean seed weight and seed shape. Eighteen candidate genes that may be involved in the regulation of soybean seed size were screened by gene functional annotation and GO enrichment analysis.

Transcriptomic and Metabolomic Analyses Reveal the Key Genes Related to Shade Tolerance in Soybean.

Soybean (Glycine max) is an important crop, rich in proteins, vegetable oils and several other phytochemicals, which is often affected by light during growth. However, the specific regulatory mechanisms of leaf development under shade conditions have yet to be understood. In this study, the transcriptome and metabolome sequencing of leaves from the shade-tolerant soybean 'Nanxiadou 25' under natural light (ND1) and 50% shade rate (SHND1) were carried out, respectively. A total of 265 differentially expressed genes (DEGs) were identified, including 144 down-regulated and 121 up-regulated genes. Meanwhile, KEGG enrichment analysis of DEGs was performed and 22 DEGs were significantly enriched in the top five pathways, including histidine metabolism, riboflavin metabolism, vitamin B6 metabolism, glycerolipid metabolism and cutin, suberine and wax biosynthesis. Among all the enrichment pathways, the most DEGs were enriched in plant hormone signaling pathways with 19 DEGs being enriched. Transcription factors were screened out and 34 differentially expressed TFs (DETFs) were identified. Weighted gene co-expression network analysis (WGCNA) was performed and identified 10 core hub genes. Combined analysis of transcriptome and metabolome screened out 36 DEGs, and 12 potential candidate genes were screened out and validated by quantitative real-time polymerase chain reaction (qRT-PCR) assay, which may be related to the mechanism of shade tolerance in soybean, such as ATP phosphoribosyl transferase (ATP-PRT2), phosphocholine phosphatase (PEPC), AUXIN-RESPONSIVE PROTEIN (IAA17), PURPLE ACID PHOSPHATASE (PAP), etc. Our results provide new knowledge for the identification and function of candidate genes regulating soybean shade tolerance and provide valuable resources for the genetic dissection of soybean shade tolerance molecular breeding.

Transcription Activation of Rab8A by PEA3 Augments Progression of Esophagus Cancer by Activating the Wnt/ß-Catenin Signaling Pathway.

Background: Rab8A has been reported as an oncogenic gene in breast and cervical cancer. However, the function and molecular mechanism of Rab8A in esophagus cancer has not been reported. Methods: Rab8A expression was detected by qPCR and western blotting assays, small interference RNA (siRNA) was applied to reduce Rab8A expression, and the biological behaviors of esophagus cancer cells were estimated by cell counting kit-8, colony formation, and transwell and western blotting assays. The transcriptional factor of Rab8A was verified by dual-luciferase assay and chromatin immunoprecipitation assay. The protein expression of key genes in the Wnt/ß-catenin signaling pathway was determined by western blotting assay. M435-1279 was used to suppress the Wnt/ß-catenin signaling pathway. Results: A significant increase of Rab8A expression has been found in esophagus cancer cells. Knockdown of Rab8A suppressed the viability, colony formation, migration, and invasion abilities of esophagus cancer cells and induced apoptosis. PEA3 transcriptionally regulated Rab8A expression and promoted the viability, colony formation, migration, and invasion abilities of esophagus cancer cells and blocked apoptosis, which were diminished by si-Rab8A transfection. Additionally, the expression levels of key genes related to the Wnt/ß-catenin signaling pathway were strengthened by PEA3 overexpression, which were reduced by si-Rab8A transfection. M435-1279 treatment significantly reduced the viability and colony formation of esophagus cancer cells. Conclusions: The data showed that Rab8A was transcriptionally regulated by PEA3 and promoted the malignant behaviors of esophagus cancer cells by activating the Wnt/ß-catenin pathway. The above results indicated that Rab8A may be considered as a promising biomarker for diagnosis and precision treatment in esophagus cancer.

Preparation of NIR-Responsive Gold Nanocages as Efficient Carrier for Controlling Release of EGCG in Anticancer Application.

Hepatocellular carcinoma (HCC) is a type of cancer that has a restricted therapy option. Epigallocatechin gallate (EGCG) is one of the main biologically active ingredients in tea. A large number of studies have shown that EGCG has preventive and therapeutic effects on various tumors. In addition, the development of near-infrared (NIR)-responsive nano-platforms has been attracting cancer treatment. In this work, we designed and synthesized a strategy of gold nanocages (AuNCs) as an efficient carrier for controlling release of EGCG for anti-tumor to achieve the synergistic functions of NIR-response and inhibited tumor cell proliferation. The diameter of AuNCs is about 50 nm and has a hollow porous (8 nm) structure. Thermal imaging-graphic studies proved that the AuNCs-EGCG obtained have photothermal response to laser irradiation under near-infrared light and still maintain light stability after multiple cycles of laser irradiation. The resulted AuNCs-EGCG reduced the proliferation rate of HepG2 cells to 50% at 48 h. Western blot analysis showed that NIR-responsive AuNCs-EGCG can promote the expression of HepG2 cell apoptosis-related proteins HSP70, Cytochrome C, Caspase-9, Caspase-3, and Bax, while the expression of Bcl-2 is inhibited. Cell confocal microscopy analysis proved that AuNCs-EGCG irradiated by NIR significantly upregulates Caspase-3 by nearly 2-fold and downregulates Bcl-2 by nearly 0.33-fold, which is beneficial to promote HepG2 cell apoptosis. This study provides useful information for the NIR-responsive AuNCs-EGCG as a new type of nanomedicine for HCC.

Metformin Protects against Spinal Cord Injury and Cell Pyroptosis via AMPK/NLRP3 Inflammasome Pathway.

Spinal cord injury (SCI) is an extreme neurological impairment with few effective drug treatments. Pyroptosis is a recently found and proven type of programmed cell death that is characterized by a reliance on inflammatory caspases and the release of a large number of proinflammatory chemicals. Pyroptosis differs from other cell death mechanisms such as apoptosis and necrosis in terms of morphological traits, incidence, and regulatory mechanism. Pyroptosis is widely involved in the occurrence and development of SCI. In-depth research on pyroptosis will help researchers better understand its involvement in the onset, progression, and prognosis of SCI, as well as provide new therapeutic prevention and treatment options. Herein, we investigated the role of AMPK-mediated activation of the NLRP3 inflammasome in the neuroprotection of MET-regulated pyroptosis. We found that MET treatment reduced NLRP3 inflammasome activation by activating phosphorylated AMPK and reduced proinflammatory cytokine (IL-1ß, IL-6, and TNF-α) release. At the same time, MET improved motor function recovery in rats after SCI by reducing motor neuron loss in the anterior horn of the spinal cord. Taken together, our study confirmed that MET inhibits neuronal pyroptosis after SCI via the AMPK/NLRP3 signaling pathway, which is mostly dependent on the AMPK pathway increase, hence decreasing NLRP3 inflammasome activation.

Quantitative evaluation of maxillary interradicular bone with cone-beam computed tomography for bicortical placement of orthodontic mini-implants.

INTRODUCTION: The purpose of this study was to propose a protocol for safe bicortical placement of mini-implants by measuring the interradicular spaces of the maxillary teeth and the bone quality. METHODS: Cone-beam computed tomography data were obtained from 50 adults. Three-dimensional reconstructions and measurements were made with SimplantPro software (Materialise, Leuven, Belgium). For each interradicular site, the bone thicknesses and interradicular distances at the planes 1.5, 3, 6, and 9 mm above the cementoenamel junction were measured. Standard bone units were defined to evaluate the influences of bone density and the different placement patterns on the stability of the mini-implants. RESULTS: The safe interradicular sites in the maxilla for bicortical placement of 1.5-mm-diameter mini-implants were in all planes between the first and second premolars, and between the second premolar and the first molar. The safe palatal sites were between the first and second molars, and the safe labial sites of the 9-mm plane were between the central incisors, and between the lateral incisor and the canine. The safe buccal sites of the 6- and 9-mm planes were between the first and second molars, and the safe buccal sites of the 3-, 6-, and 9-mm planes were between the canine and the first premolar. Most bone thicknesses were from 8 to 12 mm. The optimal placement angle between the second premolar and the first molar was 58°. Bicortical placement could have more standard bone units than unicortical placement in the maxilla. CONCLUSIONS: Bicortical placement would be more stable in the maxilla. For the site between the molars, special care should be taken at a plane higher than 6 mm to prevent maxillary sinus penetration. The most favorable interradicular area in the maxilla was between the second premolar and the first molar.

ShRNA-mediated knock-down of CXCR7 increases TRAIL-sensitivity in MCF-7 breast cancer cells.

This study aims to investigate the effects of CXCR7-shRNA on TRAIL-mediated apoptosis and suppression of invasive migration and the underlying mechanisms. (1) We constructed CXCR-7-shRNA lentiviral vectors and confirmed their silencing efficiency in MCF-7 cells by RT-PCR analysis. (2) The effects of CXCR7 and/or TRAIL on cell proliferation were examined by MTT assay. (3) Trans well invasion assay was used to examine the effects of CXCR7 silencing and/or TRAIL on MCF-7 cell invasive migration. (4) Expression of Caspase-3, and Caspase-8, and MMP-2 and MMP-9 proteins was examined by Western blot analysis. (1) Viral titers were 2.95 × 10(8) TU/ml, 3.01 × 10(8) TU/ml, 3.26 × 10(8) TU/ml, and 3.08 × 10(8) TU/ml, respectively. (2) CHXR7 shRNAs markedly decreased CXCR7 mRNA expression in MCF-7 cells, among which CXCR7-shRNA-1 showed significantly higher rate of inhibition (P < 0.05). (3) Combination of TRAIL and CXCR7-shRNA-1 resulted in marked suppression of cell proliferation in time-dependent manner (P < 0.05). (4) Cell invasion capacity was inhibited in each experimental group as compared to blank control group at 48 h post treatments (P < 0.05). Among them, combination of TRAIL and CXCR7-shRNA had the highest inhibitory effect (P < 0.05). (5) Western blot analysis indicated that TRAIL alone does not affect CXCR7 expression, but either TRAIL + CXCR7 shRNA or CXCR7 shRNA alone markedly suppressed CXCR7 protein expression. Furthermore, combination of TRAIL and CXCR-7-shRNA significantly increased Caspase-3 and Caspase-8 expression and decreased MMP-2 and MMP-9 expression (P < 0.05). Knock-down of CXCR-7 expression leads to augmented TRAIL-mediated suppression of MCF-7 cell proliferation and invasion.

RNA interference targeting human integrin α6 suppresses the metastasis potential of hepatocellular carcinoma cells.

BACKGROUND: Increased metastasis has been proved to be associated with a poor prognosis for hepatocellular carcinoma (HCC). There are higher-level expressions of integrin α6 in the tissues of HCC patients with a higher fatality rate. The aim of this study is to investigate the effect of short hairpin RNA (shRNA) silencing integrin α6 expression on the proliferation and metastasis in HCC cell lines. METHODS: Two human HCC cell lines, HepG2 and Bel-7402 were transfected with shRNA targeting human integrin α6. Protein and mRNA expression level were determined by western blot and real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) to detect the transfected efficacy. The metastasis potential of HCC cells was evaluated by their proliferation, adhesion and invasion abilities. Cell proliferation was measured by MTT assay. Adhesion ability was measured by adhesion and spreading assays. The expression of matrix metalloproteinases (MMPs) was measured by qRT-PCR. The potential of invasion was measured by qRT-PCR and Transwell chamber assay. PI3K inhibitor LY294002 was used to explore the signal pathways of integrin α6 in HCC cells. RESULTS: Western blot and qRT-PCR detection showed that over 75% of integrin α6 expression in HCC cells was through knockdown by shRNA. Proliferation, adhesion, spreading and invasion of HepG2 and Bel-7402 cells were dramatically decreased in cells transfected with shRNA compared to the control cells. P-ERK and p-AKT were reduced by shRNA targeting integrin α6 and PI3K inhibitor LY294002. CONCLUSION: Knockdown integrin α6 can inhibit the proliferation and metastasis of HCC cells through PI3K/ARK and MAPK/ERK signal pathways by shRNA in vitro. Integrin α6 can mediate the metastasis potential, and can be used as a candidate target for therapy in HCC resulting in improved patients' survival.

The novel gene LRP15 is regulated by DNA methylation and confers increased efficiency of DNA repair of ultraviolet-induced DNA damage.

LRP15 is a novel gene cloned from lymphocytic cells, and its function is still unknown. Bioinformatic data showed that LRP15 might be regulated by DNA methylation and had an important role in DNA repair. In this study, we investigate whether the expression of LRP15 is regulated by DNA methylation, and whether overexpression of LRP15 increases efficiency of DNA repair of UV-induced DNA damage in HeLa cells. The results showed (1) the promoter of LRP15 was hypermethylated in HeLa cells, resulting a silence of its expression. Gene expression was restored by a demethylating agent, 5-aza-2'-deoxycytidine, but not by a histone deacetylase inhibitor, trichostatin A; (2) overexpression of LRP15 inhibited HeLa cell proliferation, and the numbers of cells in the G2/M phase of the cell cycle in cells transfected with LRP15 increased about 10% compared with controls; (3) cyclin B1 level was much lower in cells overexpressing LRP15 than in control cells; and (4) after exposure to UV radiation, the LRP15-positive cells showed shorter comet tails compared with the LRP15-negative cells. From these results we conclude that the expression of LRP15 is controlled by methylation in its promoter in HeLa cells, and LRP15 confers resistance to UV damage and accelerates the DNA repair rate.

Transcription factors Xbp-1, Blimp-1, and BSAP are involved in the regulation of plasmacytic differentiation induced by 2-methoxyestradiol in myeloma cell lines.

Our previous studies demonstrated that a low concentration of 2-methoxyestradiol (2ME2) could induce the differentiation of myeloma cell lines and CD138+ primary myeloma cells from myeloma patients and up-regulate the expression of messenger RNA (mRNA) and protein for the gene encoding X-box binding protein 1 (Xbp-1) in myeloma cell lines. In the present study, we used phosphorothioated antisense oligodeoxynucleotides (ASODN) to investigate the roles and interactions of transcription factors Xbp-1, B-lymphocyte induced maturation protein 1 (Blimp-1), and PAX-5-encoded B-cell-specific activator protein (BSAP), which are thought to be involved in the regulation of B-lymphocytic or plasmacytic differentiation. Blimp-1 ASODN and Xbp-1 ASODN clearly inhibited myeloma cell differentiation and significantly partially inhibited the differentiation effects induced by 2ME2 at low concentration, whereas PAX-5 ASODN clearly induced myeloma cell differentiation and significantly enhanced 2ME2-induced differentiation effects. Moreover, after incubation with Blimp-1 ASODN, the level of Xbp-1 mRNA clearly declined, whereas the level of PAX-5 mRNA significantly increased in myeloma cells. These results demonstrate that transcription factors Xbp-1, Blimp-1, and PAX-5-encoded BSAP play important roles in the regulation of plasmacytic differentiation and exert their effects on differentiation induced by low 2ME2 concentrations. Our primary study provided the rationale for a promising strategy-the future application of transcription-factor ASODN for clinical patients.

Preliminary investigation of 2-methoxyestradiol inducing differentiation of myeloma cell line CZ-1.

This study was aimed to investigate whether 2-methoxyestradiol (2ME2) could exert effect of inducing differentiation on myeloma cells. A myeloma cell line CZ-1 secreting lambda light chain protein was used as an object of study. The CZ-1 cell morphology was observed by Wright's staining, the CD49e expression on cell surface after treatment with 2ME2 was detected by flow cytometry, the concentration of lambda light chain protein in the supernatant was assayed by immuno-scattering turbidity method. The results showed that treatments with 0.1-0.5 micromol/L 2ME2 for 72 hours resulted in some mature morphological changes of CZ-1 cells, such as the ratio of karyoplasms going down, nucleolus reducing or disappearing, chromatin getting rougher and more compacted; the CD49e positive CZ-1 cells increased by 2ME2 with concentrations of 0.1 micromol/L to 0.5 micromol/L in a concentration-dependent manner. The statistical difference from the control group was significant; the concentration of lambda light chain protein increased from control group 29.3 +/- 2.77 microg/ml to 35.97 +/- 2.6 microg/ml (P < 0.05) after exposure to 0.1 micromol/L 2ME2 for 72 hours, and the treatment of 0.5 micromol/L 2ME2 up-regulated lambda light chain protein to 79.67 +/- 1.88 microg/ml (P < 0.01) continuously. It is concluded that 2ME2 at low-concentration can induce differentiation of the CZ-1 cells to mature, which provides a new, and safe strategy for myeloma therapy.

[Effect of 2-methoxyestradiol on differentiation of primary myeloma cells].

In order to investigate the differentiation-inducing effect of 2-methoxyestradiol (2ME2), an estrogen derivative, on CD138+ (Syndecan-1) primary myeloma cells from 7 patients with myeloma, primary myeloma cells from 7 patients were enriched by using CD138 immunomagenetic beads. The enriched CD138+ (Syndecan-1) myeloma cells treated with 0.5 micromol/L 2ME2 for 36 h and 72 hours were used to observe the differentiation changes with expression of CD49e and to quantitatively detect the light-chain secretion in the supernatants. The results indicated that 2ME2 caused morphological and immunophenotypic changes with light-chain secretion in the supernatant, and the typical features of differentiation of CD138+ (Syndecan-1) primary myeloma cells. CD138+ (Syndecan-1) myeloma cells became more and more mature in morphology, with decreased ratio of nucleus to plasma, disappearance of nucleoli, and pyknosis of chromatin. The result of detecting the expression of CD49e of CD138+ (Syndecan-1) myeloma cells showed the obvious up-regulation of CD49e expression after exposure to 2ME2 for 72 hours. Quantitative assay for light chain secretion in the supernatant of bone marrow CD138+ cells from patients showed remarkable increment at 72 hours. It is concluded that lower concentrations of 2-methoxyestradiol can induce differentiation of bone marrow CD138+ cells from multiple myeloma patients.

2-Methoxyestradiol at low dose induces differentiation of myeloma cells.

Previous studies showed that 2-methoxyestradiol (2ME2) could suppress the proliferation of myeloma cells and induce their apoptosis. In the present study, we found that treatments with low-concentration of 2ME2 resulted in some maturing morphological changes of myeloma cells. Flow cytometric analysis showed that the expression of CD49e on the myeloma cells surface was significantly increased by 2ME2. Moreover, 2ME2 increased the secretion of light chain protein remarkably. Furthermore, the expressions of transcription factor XBP-1 mRNA and protein were also up-regulated. These results demonstrated that 2ME2 at low-concentration could induce differentiation of the myeloma cells, which would provide a new, safe strategy for myeloma therapy.

[Effect of 2-methoxyestradiol on cell differentiation of myeloma cell line CZ-1].

OBJECTIVE: To investigate the differentiation induction effect of 2-methoxyestradiol (2ME2), an estrogen derivative on myeloma cell line CZ-1. METHODS: The changes of CZ-1 cells in morphology, expression of surface CD49e and quantity of light chain secretion in the supernatant were observed when treated with 0.1 approximately 0.5 micromol/L 2ME2 for 48 h. RESULTS: 2ME2 could induce differentiation of CZ-1 cells. The cells appeared decreased in size of nucleus, increased in cytoplasma, decreased in the ratio of nucleus to plasma, decreased in number or disappearance of nucleolus, and thickness and pyknosis of chromatin. The expression of CD49e was increased from (12.20 +/- 1.57)% to (24.80 +/- 1.26)% (P < 0.05). Light chain secretion in the supernatant was increased from (35.97 +/- 2.60) microg/ml to (79.67 +/- 1.88) microg/ml (P < 0.05). CONCLUSION: Low concentrations of 2ME2 could induce differentiation of myeloma cell line CZ-1.

[Investigation of the effect of 2-methoxyestradiol and arsenic trioxide on the apoptosis-associated gene expression profile of myeloma cells].

OBJECTIVE: To explore the effect of 2-methoxyestradiol (2ME2) and arsenic trioxide (As2O3) on the apoptosis related gene expression in multiple myeloma cell line CZ-1. METHODS: Total RNA was isolated from CZ-1 cells which had been treated with 2ME2 and As2O3 at an apoptosis-inducing concentration and reverse-transcribed into a cDNA probe labeled with Bio-16-dUTP, and then hybridized it with a microarray containing up to 96 key genes involved in apoptosis. The gene expression profile of the 2ME2 and As2O3 treated CZ-1 cells were analyzed with GEArray Analyzer software. The microarray results were confirmed by RT-PCR. RESULTS: As2O3 treatment caused the alteration in the expression of 52 genes (54.2% of total genes on microarray). Among them, 42 (80.8%) were upregulated and 10 (19.2%) were downregulated. The upregulated genes were mainly involved in caspases family, P53 and ATM pathway, death effector domain family, TNF receptor family and CIDE family. 2ME2 treatment resulted in the alteration of 42 genes (43.8% of the total genes on microarray). Of them, 32 (76.2%) were downregulated and 10 (23.8%) were upregulated. The downregulated genes mainly belonged to bcl-2 family, inhibitor of apoptosis protein family (IAP), TRAF family, TNF ligand family, and CARD family. CONCLUSION: 2ME2 and As2O3 induce the CZ-1 cells apoptosis by different pathways. As2O3 mainly induces upregulation of proapoptotic genes, and 2ME2 downregulation of anti-apoptotic genes expression.

[Effect of 2-methoxyestradiol on proliferation and apoptosis of myeloma cell lines].

The objective was to explore the in vitro effects of growth inhibition and apoptosis induction of 2-methoxyestradiol (2ME2), an estrogen derivative, on seven myeloma cell lines NCI-H929, HS-sultan, KM3, SKO-007, CZ-1, U266 and LP-1and to observe its synergistic effects in combination with some other drugs, such as dexamethasone, As(2)O(3), thalidomide and zoledronic acid. Seven myeloma cell lines NCI-H929, HS-sultan, KM3, SKO-007, CZ-1, U266 and LP-1 were cultured at different concentrations with or without dexamethasone, As(2)O(3), thalidomide and zoledronic acid. Cell viability was assessed by trypan blue assay, plasma cell labeling index (PCLI) was detected by BrdU assay, terminal-deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) assay were used to determine apoptosis cells in situ. Synergistic effects of 2ME2 in combination with other drugs were judged by King's formula. The results showed that after treatment with 1, 4, 8, 12, 16 micromol/L 2ME2 at 12, 24, 36 and 48 hours respectively, 2ME2 caused a dose- and time-dependent inhibition of the cell viability. The concentration of 50% growth inhibition (IC(50)) was between (20.8 +/- 0.27) and (34.1 +/- 0.57) micromol/L. After treatment with 12 micromol/L 2ME2 within 24 hours, 2ME2 led to a progressive decline in the fraction of S-phase cells by BrdU assay, plasma cell labeling index (PCLI) declined from (30.14 +/- 4.28)% to (14.71 +/- 6.27)% (P < 0.05). After treatment with 1, 4, 8, 12, 16 micromol/L 2ME2 at 12, 24, 36 and 48 hours respectively, 2ME2 can induce a dose- and time-dependent apoptosis of myeloma cell lines. The percentage of apoptosis was between 9% - 33% (P < 0.05). Q value of synergistic effects was between 1.13 to 1.43. It is concluded that 2ME2 can inhibit proliferation and induce apoptosis of myeloma cell lines and has synergistic effects with dexamethasone, As(2)O(3), thalidomide and zoledronic acid.

[Molecular mechanism of myeloma cell line differentiation induced by 2-methoxyestradiol].

OBJECTIVE: To study the molecular mechanism of differentiation induction by 2-methoxyestradiol (2ME2) of myeloma cell lines. METHODS: Differentiation induction effect on myeloma cell lines LP-1, CZ-1 and NCI-H929 which were incubated with 2ME2 and XBP-1, Blimp-1, pax-5 phosphorothioate antisense oligodeoxynucleotide (ASODN) was evaluated by cell morphology, CD49e expression, quantitation of light chain secretion, and the level of pax-5 and XBP-1 mRNA expression. RESULTS: 2ME2 caused morphological, immunophenotypic and the supernatant light chain secretion changes typical of differentiation in all the three myeloma cell lines. 2ME2 up-regulated the XBP-1 mRNA expression. XBP-1 and Blimp-1 ASODNs partially inhibited the differentiation of LP-1, CZ-1, NCI-H929 cells induced by 2ME2; whereas pax-5 ASODN did the contrary. After incubated with pax-5 ASODN for 72 hours, LP-1, CZ-1, NCI-H929 cells exhibited characteristic morphologic feature of differentiation. The expression of CD49e was increased statistically (P < 0.05). Light chain secretion in the supernatant was also increased statistically (P < 0.05). After incubation with Blimp-1 ASODN, the level of XBP-1 mRNA was declined, while the level of pax-5 mRNA increased. CONCLUSION: 2ME2 could induce cell differentiation and up-regulate XBP-1 mRNA expression in myeloma cell lines. Blimp-1 could help 2ME2 with inducing differentiation of myeloma cells through downregulating pax-5 mRNA and upregulating XBP-1 mRNA.