Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An early event in the pathogenesis of neuroblastoma (NB), a tumor derived from embryonal neural crest tissue, appears to be the arrested differentiation of neuroblasts. However, NB cells can be induced to differentiate in vitro with numerous chemicals including retinoic acid (RA) and dibutyryl cyclic AMP (db-cAMP). One family of transcription factors, encoded by the homeobox (HOX) genes, plays a crucial role in Drosophila, Xenopus, and mammalian embryonic differentiation and development. We have previously identified six HOX genes (HOXC6, HOXC8, HOXD1, HOXD4, HOXD8, and HOXD9), by a sensitive PCR-based approach, in a cDNA library prepared from the human LA-N-5 NB cell line induced to differentiate with RA. In this report, we studied the regulation of these six HOX genes in a series of NB cell lines chemically induced to differentiate. Untreated NB cells express low or undetectable levels of HOX mRNA, and HOXC8 remains undetectable in the induced cells. However, a significant induction of HOXC6, HOXD1, and HOXD8 expression is seen in the RA-treated NB cell lines, albeit with different patterns and degree of up-regulation. db-cAMP treatment also induced HOXC6 and HOXD8 expression in two of the three NB cell lines analyzed. Low levels of HOXD4 and HOXD9 induction were observed in two and one RA-treated NB cell line, respectively. Up-regulation of HOXC6, HOXD1, and HOXD8 expression in human NB cells, chemically induced to differentiate, appears to be associated with maturation toward a differentiated neuronal phenotype.
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PMID:Up-regulation of HOXC6, HOXD1, and HOXD8 homeobox gene expression in human neuroblastoma cells following chemical induction of differentiation. 750 71

Retinoic acid (RA) can induce growth arrest and neuronal differentiation of neuroblastoma cells and has been used in clinic for treatment of neuroblastoma. It has been reported that RA induces the expression of several HOXD genes in human neuroblastoma cell lines, but their roles in RA action are largely unknown. The HOXD cluster contains nine genes (HOXD1, HOXD3, HOXD4, and HOXD8-13) that are positioned sequentially from 3' to 5', with HOXD1 at the 3' end and HOXD13 the 5' end. Here we show that all HOXD genes are induced by RA in the human neuroblastoma BE(2)-C cells, with the genes located at the 3' end being activated generally earlier than those positioned more 5' within the cluster. Individual induction of HOXD8, HOXD9, HOXD10 or HOXD12 is sufficient to induce both growth arrest and neuronal differentiation, which is associated with downregulation of cell cycle-promoting genes and upregulation of neuronal differentiation genes. However, induction of other HOXD genes either has no effect (HOXD1) or has partial effects (HOXD3, HOXD4, HOXD11 and HOXD13) on BE(2)-C cell proliferation or differentiation. We further show that knockdown of HOXD8 expression, but not that of HOXD9 expression, significantly inhibits the differentiation-inducing activity of RA. HOXD8 directly activates the transcription of HOXC9, a key effector of RA action in neuroblastoma cells. These findings highlight the distinct functions of HOXD genes in RA induction of neuroblastoma cell differentiation.
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PMID:Functional dissection of HOXD cluster genes in regulation of neuroblastoma cell proliferation and differentiation. 2287 80

Pediatric brain tumors such as atypical teratoid rhabdoid tumors (ATRTs) are highly aggressive and predominantly occur in young children. A characteristic feature of ATRT is aberrations of the SMARCB1 (hSNF5/INI1) gene. Developmental gene defects may play an important role in the biology of pediatric brain tumors. HOX genes are transcription factors that play a pivotal role in anterior-posterior body axis patterning and are misexpressed in tumors such as lung carcinoma, neuroblastoma, and glioma. HOX genes are also known to be associated with long noncoding RNAs (lncRNAs) such as HOTAIR, which induces transcriptional silencing of the HOXD locus by recruiting polycomb repressive complex 2 to the HOXD locus. In this study, transcriptome analysis using the nanoString platform was performed, and expression of the HOX and HOTAIR genes was studied in pediatric tumors: 20 ATRTs, 10 ependymomas, 10 medulloblastomas, six glioblastoma multiforme, and nine juvenile pilocytic astrocytomas (JPAs). Results indicate that in ATRTs, medulloblastomas, and JPAs, the HOTAIR and HOXC genes are highly expressed; however, HOXD8-10 genes are not silenced. In ependymomas, there is low expression of the HOXC, HOTAIR, and HOXD8-10 genes. These interesting results need to be elucidated further so that the functions of these genes in pediatric tumors is understood.
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PMID:Expression of the HOX genes and HOTAIR in atypical teratoid rhabdoid tumors and other pediatric brain tumors. 2508 2

Homeobox (HOX) genes are conserved transcription factors which determine the anterior-posterior body axis patterning. HOXD8 is a member of HOX genes deregulated in several tumors such as lung carcinoma, neuroblastoma, glioma and colorectal cancer (CRC) in a context-dependent manner. In CRC, HOXD8 is downregulated in cancer tissues and metastatic foci as compared to normal tissues. Whether HOXD8 acts as a tumor suppressor of malignant progression and metastasis is still unclear. Also, the underlying mechanism of its function including the downstream targets is totally unknown. Here, we clarified the lower expression of HOXD8 in clinical colorectal cancer vs. normal colon tissues. Also, we showed that stable expression of HOXD8 in colorectal cancer cells significantly reduced the cell proliferation, anchorage-independent growth and invasion. Further, using The Cancer Genome Atlas (TCGA), we identified the genes associated with HOXD8 in order to demonstrate its function as a suppressor or a promoter of colorectal carcinoma. Among inversely related genes, apoptotic inhibitors like STK38 kinase and MYC were shown to be negatively associated with HOXD8. We demonstrated the ability of HOXD8 to upregulate executioner caspases 6 & 7 and cleaved PARP, thus inducing the apoptotic events in colorectal cancer cells.
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PMID:HOXD8 exerts a tumor-suppressing role in colorectal cancer as an apoptotic inducer. 2845 70