TIAM2S-positive microglia enhance inflammation and neurotoxicity through soluble ICAM-1-mediated immune priming.

TIAM Rac1-associated GEF 2 short form (TIAM2S) as an oncoprotein alters the immunity of peripheral immune cells to construct an inflammatory tumor microenvironment. However, its role in the activation of microglia, the primary innate immune cells of the brain, and neuroinflammation remains unknown. This study investigated the mechanism underlying TIAM2S shapes immune properties of microglia to facilitate neuron damage. Human microglial clone 3 cell line (HMC3) and human brain samples were applied to determine the presence of TIAM2S in microglia by western blots and double immunostaining. Furthermore, TIAM2S transgenic mice combined with multiple reconstituted primary neuron-glial culture systems and a cytokine array were performed to explore how TIAM2S shaped immune priming of microglia and participated in lipopolysaccharide (LPS)-induced neuron damage. TIAM2S protein was detectable in HMC3 cells and presented in a small portion (~11.1%) of microglia in human brains referred to as TIAM2S-positive microglia. With the property of secreted soluble factor-mediated immune priming, TIAM2S-positive microglia enhanced LPS-induced neuroinflammation and neural damage in vivo and in vitro. The gain- and loss-of-function experiments showed soluble intercellular adhesion molecule-1 (sICAM-1) participated in neurotoxic immune priming of TIAM2S+ microglia. Together, this study demonstrated a novel TIAM2S-positive microglia subpopulation enhances inflammation and neurotoxicity through sICAM-1-mediated immune priming.

A novel STAT3/ NFκB p50 axis regulates stromal-KDM2A to promote M2 macrophage-mediated chemoresistance in breast cancer.

BACKGROUND: Lysine Demethylase 2A (KDM2A) plays a crucial role in cancer cell growth, differentiation, metastasis, and the maintenance of cancer stemness. Our previous study found that cancer-secreted IL-6 can upregulate the expression of KDM2A to promote further the transition of cells into cancer-associated fibroblasts (CAFs). However, the molecular mechanism by which breast cancer-secreted IL-6 regulates the expression of KDM2A remains unclear. Therefore, this study aimed to elucidate the underlying molecular mechanism of IL-6 in regulating KDM2A expression in CAFs and KDM2A-mediated paclitaxel resistance in breast cancer. METHODS: The ectopic vector expression and biochemical inhibitor were used to analyze the KDM2A expression regulated by HS-578 T conditioned medium or IL-6 in mammary fibroblasts. Immunoprecipitation and chromatin immunoprecipitation assays were conducted to examine the interaction between STAT3 and NFκB p50. M2 macrophage polarization was assessed by analyzing M2 macrophage-specific markers using flow cytometry and RT-PCR. ESTIMATE algorithm was used to analyze the tumor microenvironment-dominant breast cancer samples from the TCGA database. The correlation between stromal KDM2A and CD163 + M2 macrophages was analyzed using the Pearson correlation coefficient. Cell viability was determined using trypan blue exclusion assay. RESULTS: IL-6 regulates gene expression via activation and dimerization of STAT3 or collaboration of STAT3 and NFκB. However, STAT3, a downstream transcription factor of the IL-6 signaling pathway, was directly complexed with NFκB p50, not NFκB p65, to upregulate the expression of KDM2A in CAFs. Enrichment analysis of immune cells/stromal cells using TCGA-breast cancer RNA-seq data unveiled a positive correlation between stromal KDM2A and the abundance of M2 macrophages. CXCR2-associated chemokines secreted by KDM2A-expressing CAFs stimulated M2 macrophage polarization, which in turn secreted CCL2 to increase paclitaxel resistance in breast cancer cells by activating CCR2 signaling. CONCLUSION: This study revealed the non-canonical molecular mechanism of IL-6 secreted by breast cancer upregulated KDM2A expression in CAFs via a novel STAT3/NFκB p50 axis, which STAT3 complexed with NFκB p50 in NFκB p50 binding motif of KDM2A promoter. KDM2A-expressing CAFs dominantly secreted the CXCR2-associated chemokines to promote M2 macrophage polarization and enhance paclitaxel resistance in breast cancer. These findings underscore the therapeutic potential of targeting the CXCR2 or CCR2 pathway as a novel strategy for paclitaxel-resistant breast cancer.

TIAM2S as a novel regulator for serotonin level enhances brain plasticity and locomotion behavior.

TIAM2S, the short form of human T-cell lymphoma invasion and metastasis 2, can have oncogenic effects when aberrantly expressed in the liver or lungs. However, it is also abundant in healthy, non-neoplastic brain tissue, in which its primary function is still unknown. Here, we examined the neurobiological and behavioral significance of human TIAM2S using the human brain protein panels, a human NT2/D1-derived neuronal cell line model (NT2/N), and transgenic mice that overexpress human TIAM2S (TIAM2S-TG). Our data reveal that TIAM2S exists primarily in neurons of the restricted brain areas around the limbic system and in well-differentiated NT2/N cells. Functional studies revealed that TIAM2S has no guanine nucleotide exchange factor (GEF) activity and is mainly located in the nucleus. Furthermore, whole-transcriptome and enrichment analysis with total RNA sequencing revealed that TIAM2S-knockdown (TIAM2S-KD) was strongly associated with the cellular processes of the brain structural development and differentiation, serotonin-related signaling, and the diseases markers representing neurobehavioral developmental disorders. Moreover, TIAM2S-KD cells display decreased neurite outgrowth and reduced serotonin levels. Moreover, TIAM2S overexpressing TG mice show increased number and length of serotonergic fibers at early postnatal stage, results in higher serotonin levels at both the serum and brain regions, and higher neuroplasticity and hyperlocomotion in latter adulthood. Taken together, our results illustrate the non-oncogenic functions of human TIAM2S and demonstrate that TIAM2S is a novel regulator of serotonin level, brain neuroplasticity, and locomotion behavior.

Restoration of HDAC1 Enzymatic Activity after Stroke Protects Neurons from Ischemia/Reperfusion Damage and Attenuates Behavioral Deficits in Rats.

A therapeutic approach for promoting neuroprotection and brain functional regeneration after strokes is still lacking. Histone deacetylase 1 (HDAC1), which belongs to the histone deacetylase family, is involved in the transcriptional repression of cell-cycle-modulated genes and DNA damage repair during neurodegeneration. Our previous data showed that the protein level and enzymatic activity of HDAC1 are deregulated in stroke pathogenesis. A novel compound named 5104434 exhibits efficacy to selectively activate HDAC1 enzymatic function in neurodegeneration, but its potential in stroke therapy is still unknown. In this study, we adopted an induced rat model with cerebral ischemia using the vessel dilator endothelin-1 to evaluate the potential of compound 5104434. Our results indicated compound 5104434 selectively restored HDAC1 enzymatic activity after oxygen and glucose deprivation, preserved neurite morphology, and protected neurons from ischemic damage in vitro. In addition, compound 5104434 attenuated the infarct volume, neuronal loss, apoptosis, DNA damage, and DNA breaks in cerebral ischemia rats. It further ameliorated the behavioral outcomes of neuromuscular response, balance, forepaw strength, and functional recovery. Collectively, our data support the efficacy of compound 5104434 in stroke therapy and contend that it can be considered for clinical trial evaluation.

In silico identification of oncogenic potential of fyn-related kinase in hepatocellular carcinoma.

MOTIVATION: Cancer development is a complex and heterogeneous process. It is estimated that 5-10% of human genes probably contribute to oncogenesis, whereas current experimentally validated cancer genes only cover 1% of the human genome. Thus hundreds of cancer genes may still remain to be identified. To search for new genes that play roles in carcinogenesis and facilitate cancer research, we developed a systematic workflow to use information saved in a previously established tumor-associated gene (TAG) database. RESULTS: By exploiting the information of conserved protein domains from the TAG, we identified 183 potential new TAGs. As a proof-of-concept, one predicted oncogene, fyn-related kinase (FRK), which shows an aberrant digital expression pattern in liver cancer cells, was selected for further investigation. Using 68 paired hepatocellular carcinoma samples, we found that FRK was up-regulated in 52% of cases (P < 0.001). Tumorigenic assays performed in Hep3B and HepG2 cell lines revealed a significant correlation between the level of FRK expression and invasiveness, suggesting that FRK is a positive regulator of invasiveness in liver cancer cells. CONCLUSION: These findings implied that FRK is a multitalented signal transduction molecule that produces diverse biological responses in different cell types in various microenvironments. In addition, our data demonstrated the accuracy of computational prediction and suggested that other predicted TAGs can be potential targets for future cancer research. AVAILABILITY: The TAG database is available online at the Bioinformatics Center website: http://www.binfo.ncku.edu.tw/TAG/.

Direct Effects of Mifepristone on Mice Embryogenesis: An In Vitro Evaluation by Single-Embryo RNA Sequencing Analysis.

The clinical use of mifepristone for medical abortions has been established in 1987 in France and since 2000 in the United States. Mifepristone has a limited medical period that lasts <9 weeks of gestation, and the incidence of mifepristone treatment failure increases with gestation time. Mifepristone functions as an antagonist for progesterone and glucocorticoid receptors. Studies have confirmed that mifepristone treatments can directly contribute to endometrium disability by interfering with the endometrial receptivity of the embryo, thus causing decidual endometrial degeneration. However, whether mifepristone efficacy directly affects embryo survival and growth is still an open question. Some women choose to continue their pregnancy after mifepristone treatment fails, and some women express regret and seek medically unapproved mifepristone antagonization with high doses of progesterone. These unapproved treatments raise the potential risk of embryonic fatality and developmental anomalies. Accordingly, in the present study, we collected mouse blastocysts ex vivo and treated implanted blastocysts with mifepristone for 24 h. The embryos were further cultured to day 8 in vitro to finish their growth in the early somite stage, and the embryos were then collected for RNA sequencing (control n = 3, mifepristone n = 3). When we performed a gene set enrichment analysis, our data indicated that mifepristone treatment considerably altered the cellular pathways of embryos in terms of viability, proliferation, and development. The data indicated that mifepristone was involved in hallmark gene sets of protein secretion, mTORC1, fatty acid metabolism, IL-2-STAT5 signaling, adipogenesis, peroxisome, glycolysis, E2F targets, and heme metabolism. The data further revealed that mifepristone interfered with normal embryonic development. In sum, our data suggest that continuing a pregnancy after mifepristone treatment fails is inappropriate and infeasible. The results of our study reveal a high risk of fetus fatality and developmental problems when pregnancies are continued after mifepristone treatment fails.

Expression of T-cell lymphoma invasion and metastasis 2 (TIAM2) promotes proliferation and invasion of liver cancer.

The T-cell lymphoma invasion and metastasis 2 (TIAM2) gene is the homolog of human TIAM1, a Rac-specific guanine nucleotide exchange factor that plays important roles in neuron development and human malignancies. Although the role of TIAM1 is well characterized, the physiological and pathological functions of TIAM2 remain unknown. In our study, human cDNA and protein panels were evaluated for endogenous expression of TIAM2. Four hepatocellular carcinoma (HCC) cell lines and 91 HCC samples were used to demonstrate expression of TIAM2S (the short form of TIAM2) in cancer cells. In addition, HepG2 cells stably expressing TIAM2S were used for tumorigenic assays in both cellular and mouse models. We demonstrate that endogenous TIAM2S was induced in several human cancers including HCC. TIAM2S expression was undetectable in normal human liver but was induced in all HCC cell lines and in 86% (78/91) of HCC biopsies. TIAM2S expression was positively associated with TIAM1 expression, hepatitis B virus (HBV) infection and metastatic phenotype. Expression of recombinant TIAM2S in HepG2 cells promoted growth and invasiveness. In vivo study using a xenografted mouse model demonstrated that induced endogenous expression of TIAM2S converted non-invasive human HCC cells into highly aggressive vascular tumors. Further examination revealed that TIAM2S expression resulted in up-regulation of N-cadherin and vimentin, and in redistribution of E-cadherin. These findings show, for the first time, that human TIAM2S is involved in HCC pathogenesis, and that increased expression of TIAM2S promotes epithelial-to-mesenchymal transition and results in proliferation and invasion in liver cancer cells.

Prenatal diagnosis of de novo int22h1/int22h2-mediated Xq28 duplication syndrome involving RAB39B following a previous ambiguous genitalia pregnancy.

OBJECTIVE: To report a prenatal diagnosis of int22h1/int22h2-mediated Xq28 duplication syndrome. CASE REPORT: Herein, we present the case of a 28-year-old female who had a previous ambiguous genitalia pregnancy without genetic abnormality that was terminated at 23+2 weeks of gestation. The fetus of the current pregnancy harbored a de novo copy number variation at the Xq recurrent region (int22h1/int22h2-flanked; including the RAB39B gene) with a 0.397 Mb microduplication. The literature suggests the clinical manifestation of int22h1/int22h2-mediated Xq28 duplication syndrome tends to show a milder clinical phenotype in females than males. Although the fetus in this case was female, taking into consideration the parents' age and culture, the family decided to terminate this pregnancy due to the genetic abnormality. CONCLUSION: Prenatally diagnosed de novo int22h-1/int22h-2-mediated Xq28 duplication syndrome exhibits variable phenotypic traits in female fetuses.

Novel prenatally diagnosed compound heterozygous PXDN variants in fetal congenital primary aphakia and blepharophimosis.

OBJECTIVE: To precision survey a fetal congenital primary aphakia molecular etiology. CASE REPORT: A case of 42 years old pregnancy woman prenatal diagnostic examination by amniocentesis conducted at 17 weeks' gestation and demonstrated a normal female karyotype. Trio studies based on chromosome microarray analysis (CMA) and Sanger's genetic analysis did not detect a pathologic variant of the FOXE3 gene. Fetal congenital primary aphakia accompanied with microphthalmia detected by sonography in the second trimester (22 weeks). MRI indicated bilateral absence of the lenses, consistent with primary congenital aphakia. Due to the poor prognosis of congenital aphakia, the parents decided to terminate the fetus and provided consent for an autopsy. Pathological analysis revealed dysplasia of the anterior segment of both eyes. However, post fetal mortem extended trio whole exon sequencing (WES) and Sanger's genetic analysis identified compound heterozygous variants in the chromosomal location 2p25.3 in the PXDN gene. CONCLUSION: Extended whole exon sequencing is an important tool to study primary congenital aphakia.

Prenatally diagnosed microdeletion in the TCOF1 gene in fetal congenital primary Treacher Collins Syndrome.

OBJECTIVE: To study prenatal diagnosis of congenital Treacher Collins syndrome, an etiology of craniofacial abnormalities. CASE REPORT: We present a case of fetal craniofacial abnormalities identified by antepartum sonography screening in the third trimester (28 weeks); features of micrognathia, hypoplastic zygomatic arches and bilateral low-set microtia were detected. Due to the unknown severity of the craniofacial abnormalities and poor prognosis, the parents decided to terminate the fetus after through counselling. A normal female karyotype was detected. The parents consented to chromosome microarray analysis (CMA), which identified a de novo mutation of the TCS1 gene locus on chromosome 5. CONCLUSION: Molecular CMA is an effective tool for prenatal diagnosis of congenital craniofacial abnormalities associated with Treacher Collins syndrome.

Novel prenatally diagnosed compound heterozygous POMT2 variants in fetal congenital primary aqueduct stenosis.

OBJECTIVE: To study the etiology of congenital hydrocephalus in genetic aqueduct stenosis. CASE REPORT: We report the case of a 31-year-old pregnant female, G2P0A1, with a history of hyperthyroidism under medical control. The patient received regular prenatal care, with no specific findings in the Level II ultrasound at 21 weeks of gestation. However, hydrocephalus was noted at GA 31 weeks. High-resolution sonography and fetal magnetic resonance imaging (MRI) reported fetal aqueduct stenosis. Maternal HSV, CMV, and toxoplasma infection were not detected. Fetal karyotype and chromosomal microarray analysis (CMA) indicated a normal. After intensive counseling, the parents decided to terminate the pregnancy due to the poor fetal prognosis. Post-mortem, a whole-exome sequencing (WES) and Sanger sequencing analysis trio study identified two compound heterozygous variants in the POMT2 gene inherited from both recessive parents. In the subsequent pregnancy, a WES survey revealed inheritance of only the maternal POMT2 gene variant; a live, healthy male baby was born. CONCLUSION: Extended WES represents a precision maternal medicine tool for novel prenatal diagnosis of congenital aqueduct stenosis.

Prenatal Diagnosis Using Chromosomal Microarray Analysis in High-Risk Pregnancies.

Background: To assess the value of chromosomal microarray analysis (CMA) during the prenatal diagnosis of high-risk pregnancies. Methods: Between January 2016 and November 2021, we included 178 chorionic villi and 859 amniocentesis samples from consecutive cases at a multiple tertiary hospital. Each of these high-risk singleton pregnancies had at least one of the following indications: (1) advanced maternal age (AMA; ≥35 years; 546, 52.7%); (2) fetal structural abnormality on ultrasound (197, 19.0%); (3) high-risk first- or second-trimester Down syndrome screen (189, 18.2%), including increased nuchal translucency (≥3.5 mm; 90, 8.7%); or (4) previous pregnancy, child, or family history (105, 10.1%) affected by chromosomal abnormality or genetic disorder. Both G-banding karyotype analysis and CMA were performed. DNA was extracted directly and examined with oligonucleotide array-based comparative genomic hybridization. Results: Aneuploidies were detected by both G-banding karyotyping and CMA in 42/1037 (4.05%) cases. Among the 979 cases with normal karyotypes, 110 (10.6%) cases had copy number variants (CNVs) in CMA, including 30 (2.9%) cases with reported pathogenic and likely pathogenic CNVs ≥ 400 kb, 37 (3.6%) with nonreported VOUS, benign, or likely benign CNVs ≥ 400 kb, and 43 (4.1%) with nonreported CNVs < 400 kb. Of the 58 (5.6%) cases with aneuploidy rearrangements, 42 (4.1%) were diagnosed by both G-banding karyotyping and CMA; four inversions, six balanced translocations, and six low mosaic rates were not detected with CMA. Conclusions: CMA is an effective first step for the prenatal diagnosis of high-risk pregnancies with fetal structural anomalies found in ultrasonography or upon positive findings.

Novel Variations in the KDM5C Gene Causing X-Linked Intellectual Disability.

BACKGROUND AND OBJECTIVES: To investigate the pathogenicity of 2 novel KDM5C variations, report the clinical and neuroimaging findings, and review the available literature. METHODS: Physical examinations, structural neuroimaging studies, and exome sequence analysis were performed. KDM5C constructs were used to study the effect of the variations in transfected cells. RESULTS: We identified 2 novel variations c.2233C>G and c.3392_3393delAG in the KDM5C gene harboring from 2 Chinese families with X-linked intellectual disability (ID). The affected male patients exhibited severe ID, short stature, and facial dysmorphism. The 1 with c.3392_3393delAG additionally had epilepsy and autistic spectrum disorder (ASD). Transiently transfected mutant KDM5C constructs both reduced protein expression and stability and decreased histone demethylase activities in cells. Reviewing the available literature, we found that the associated ASD tended to occur in patients with variations near the C-terminus of KDM5C. DISCUSSION: We report the clinical, molecular genetic, and pathologic features in patients with novel variations of KDM5C. The variability of the clinical phenotype in addition to an ID may associate with altered particular parts of KDM5C.

Comorbidities associated with genetic abnormalities in children with intellectual disability.

Intellectual disability (ID) has emerged as the commonest manifestation of underlying genomic abnormalities. Given that molecular genetic tests for diagnosis of ID usually require high costs and yield relatively low diagnostic rates, identification of additional phenotypes or comorbidities may increase the genetic diagnostic yield and are valuable clues for pediatricians in general practice. Here, we enrolled consecutively 61 children with unexplained moderate or severe ID and performed chromosomal microarray (CMA) and sequential whole-exome sequencing (WES) analysis on them. We identified 13 copy number variants in 12 probands and 24 variants in 25 probands, and the total diagnostic rate was 60.7%. The genetic abnormalities were commonly found in ID patients with movement disorder (100%) or with autistic spectrum disorder (ASD) (93.3%). Univariate analysis showed that ASD was the significant risk factor of genetic abnormality (P = 0.003; OR 14, 95% CI 1.7-115.4). At least 14 ID-ASD associated genes were identified, and the majority of ID-ASD associated genes (85.7%) were found to be expressed in the cerebellum based on database analysis. In conclusion, genetic testing on ID children, particularly in those with ASD is highly recommended. ID and ASD may share common cerebellar pathophysiology.

Mifepristone Directly Disrupts Mouse Embryonic Development in Terms of Cellular Proliferation and Maturation In Vitro.

Mifepristone (RU-486), a synthetic steroid with potent antiprogestogen and anti-glucocorticoid properties, has been widely used in clinical practice. Its effect on the endometrium, ovary, and fallopian tube has been well reported in many human and animal studies. However, its direct impact on post-implantation embryos remains underexplored. Additionally, some women choose to keep their pregnancy after mifepristone treatment fails. Thus, the potential risk remains controversial. Hence, this study investigated the direct effects of mifepristone on the development of mice blastocysts in vitro in terms of implantation and post-implantation. We detected the level of progesterone (P4) associated with ovulation in vivo. The presence of progesterone receptors (PRs) in blastocysts and post-implantation embryos was also evaluated. Cultured embryos were treated directly with mifepristone. We further examined embryonic implantation and post-implantation of blastocysts in vitro to evaluate the direct effects of mifepristone on embryos by the assessment of embryonic outgrowth and differential cell staining. In the oviduct lumen, the P4 level dramatically increased at 48 h and slightly decreased at 72 and 96 h following ovulation. PR was expressed in blastocysts not only in the preimplantation stage but also in the early post-implantation period. In the evaluation of developmental stages, mifepristone significantly reduced the successful ratio of developing into the late egg cylinder and the early somite stage. In addition, it further decreased the cell number of the embryos' inner cell mass and trophectoderm. We herein provide evidence that mifepristone affects blastocyst viability directly and inhibits post-implantation embryo development in vitro. Furthermore, our data reveal a potential risk of fetus fatality and developmental problems when pregnancies are continued after mifepristone treatment fails.

HDAC1 deregulation promotes neuronal loss and deficit of motor function in stroke pathogenesis.

Stroke is a common cause of death worldwide and leads to disability and cognitive dysfunction. Ischemic stroke and hemorrhagic stroke are major categories of stroke, accounting for 68% and 32% of strokes, respectively. Each year, 15 million people experience stroke worldwide, and the stroke incidence is rising. Epigenetic modifications regulate gene transcription and play a major role in stroke. Accordingly, histone deacetylase 1 (HDAC1) participates in DNA damage repair and cell survival. However, the mechanisms underlying the role of HDAC1 in stroke pathogenesis are still controversial. Therefore, we investigated the role of HDAC1 in stroke by using a rat model of endothelin-1-induced brain ischemia. Our results revealed that HDAC1 was deregulated following stroke, and its expressional level and enzymatic activity were decreased. We also used MS-275 to inhibit HDAC1 function in rats exposed to ischemic insult. We found that HDAC1 inhibition promoted the infarct volume, neuronal loss, DNA damage, neuronal apoptosis after stroke, and levels of reactive oxygen species and inflammation cytokines. Additionally, HDAC1 inhibition deteriorated the behavioral outcomes of rats with ischemic insult. Overall, our findings demonstrate that HDAC1 participates in ischemic pathogenesis in the brain and possesses potential for use as a therapeutic target.

TIAM2S Mediates Serotonin Homeostasis and Provokes a Pro-Inflammatory Immune Microenvironment Permissive for Colorectal Tumorigenesis.

The short isoform of human TIAM2 has been shown to promote proliferation and invasion in various cancer cells. However, the roles of TIAM2S in immune cells in relation to tumor development have not been investigated. To characterize the effects of TIAM2S, we generated TIAM2S-overexpressing mouse lines and found that aged TIAM2S-transgenic (TIAM2S-TG) developed significantly higher occurrence of lymphocytic infiltration and tumorigenesis in various organs, including colon. In addition, TIAM2S-TG is more sensitized to AOM-induced colon tumor development, suggesting a priming effect toward tumorigenesis. In the light of our recent findings that TIAM2S functions as a novel regulator of cellular serotonin level, we found that serotonin, in addition to Cox2, is a unique inflammation marker presented in the colonic lesion sites in the aged TG animals. Furthermore, our results demonstrated that ectopic TIAM2S altered immunity via the expansion of T lymphocytes; this was especially pronounced in CD8+ T cells in combination with CXCL13/BCA-1 pro-inflammatory chemokine in the serum of TIAM2S-TG mice. Consequently, T lymphocytes and B cells were recruited to the lesion sites and stimulated IL-23/IL17A expression to form the tertiary lymphoid organs. Collectively, our research suggests that TIAM2S provokes a pro-inflammatory immune microenvironment permissive to colorectal tumorigenesis through the serotonin-induced immunomodulatory effects.

Association of functional polymorphisms of the human tryptophan hydroxylase 2 gene with risk for bipolar disorder in Han Chinese.

CONTEXT: The tryptophan hydroxylase 2 (TPH2) gene encodes the first (also the rate-limiting) enzyme in the serotonin biosynthetic pathway. Despite reports of possible associations between polymorphisms in human TPH2 and many psychiatric disorders, including bipolar disorder (BPD), the functional effect and susceptibility loci of such polymorphisms for BPD have not yet been identified. OBJECTIVES: To examine the association of TPH2 with BPD and to identify the functional variants that may be involved in the pathophysiological development of BPD. Design, Setting, and Patients We systematically screened all exons and promoters of the TPH2 gene in Han Chinese subjects to identify sequence variants. Association tests were conducted in 105 cases and 106 control subjects using single-locus, linkage disequilibrium, and haplotype analyses. Two promoter and one exon 2 single-nucleotide polymorphisms were examined for their functional role using a reporter gene system and enzyme activity assay, respectively. Additional statistical analysis was performed to study the interaction between the 2 TPH genes in 205 study participants with TPH1 and TPH2 genotype data. RESULTS: Significant haplotype association of TPH2 polymorphisms and BPD was identified (P < .001). In addition, allelic alteration of polymorphisms in the promoter region and exon 2 of TPH2 caused noteworthy functional losses in promoter and enzyme activities, respectively, indicating the potential susceptibility loci for BPD. We found that the odds ratio changed from 3.73 of the TAG haplotype to 4.81 or 1.68, depending on the combined effect of both TPH genotypes. These data suggested an interaction between the 2 TPH genes to confer a risk for BPD. CONCLUSIONS: This study supports the involvement of TPH2 in the etiology of BPD, and the functional single-nucleotide polymorphisms identified herein might be the susceptibility loci for BPD. Although the interaction between the 2 TPH genes merits further investigation, our findings suggest that the interactive effect should be considered in future studies of serotonin-related disorders.

Sp1-mediated ectopic expression of T-cell lymphoma invasion and metastasis 2 in hepatocellular carcinoma.

T-cell lymphoma invasion and metastasis 2 (TIAM2) is a neuron-specific protein that has been found ectopically expressed in hepatocellular carcinoma (HCC). Results from clinical specimens and cellular and animal models have shown that the short form of TIAM2 (TIAM2S) functions as an oncogene in the tumorigenesis of liver cancer. However, the regulation of TIAM2S ectopic expression in HCC cells remains largely unknown. This study aimed to identify the mechanism underlying the ectopic expression of TIAM2S in liver cancer cells. In this report, we provide evidence illustrating that Sp1 binds directly to the GC box located in the TIAM2S core promoter. We further demonstrated that overexpression of Sp1 in HepaRG cells promotes endogenous TIAM2S mRNA and protein expressions, and knockdown of Sp1 in 2 HCC cell lines, HepG2 and PLC/PRF/5, led to a substantial reduction in TIAM2S mRNA and protein in these cells. Of 60 paired HCC samples, 70% showed a significant increase (from 1.1- to 3.6-fold) in Sp1 protein expression in the tumor cells. The elevated Sp1 expression was highly correlated with both TIAM2S mRNA and protein expressions in these samples. Together, these results illustrate that Sp1 positively controls TIAM2S transcription and that Sp1-mediated transcriptional activation is essential for TIAM2S ectopic expression in liver cancer cells.

Development of a microarray for two rice subspecies: characterization and validation of gene expression in rice tissues.

BACKGROUND: Rice is one of the major crop species in the world helping to sustain approximately half of the global population's diet especially in Asia. However, due to the impact of extreme climate change and global warming, rice crop production and yields may be adversely affected resulting in a world food crisis. Researchers have been keen to understand the effects of drought, temperature and other environmental stress factors on rice plant growth and development. Gene expression microarray technology represents a key strategy for the identification of genes and their associated expression patterns in response to stress. Here, we report on the development of the rice OneArray® microarray platform which is suitable for two major rice subspecies, japonica and indica. RESULTS: The rice OneArray® 60-mer, oligonucleotide microarray consists of a total of 21,179 probes covering 20,806 genes of japonica and 13,683 genes of indica. Through a validation study, total RNA isolated from rice shoots and roots were used for comparison of gene expression profiles via microarray examination. The results were submitted to NCBI's Gene Expression Omnibus (GEO). Data can be found under the GEO accession number GSE50844 (http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE50844). A list of significantly differentially expressed genes was generated; 438 shoot-specific genes were identified among 3,138 up-regulated genes, and 463 root-specific genes were found among 3,845 down-regulated genes. GO enrichment analysis demonstrates these results are in agreement with the known physiological processes of the different organs/tissues. Furthermore, qRT-PCR validation was performed on 66 genes, and found to significantly correlate with the microarray results (R = 0.95, p < 0.001***). CONCLUSION: The rice OneArray® 22 K microarray, the first rice microarray, covering both japonica and indica subspecies was designed and validated in a comprehensive study of gene expression in rice tissues. The rice OneArray® microarray platform revealed high specificity and sensitivity. Additional information for the rice OneArray® microarray can be found at http://www.phalanx.com.tw/index.php.