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H19 (gene)
H19 is a gene for a long noncoding RNA, found in humans and elsewhere. H19 has a role in the negative regulation (or limiting) of body weight and cell proliferation. This gene also has a role in the formation of some cancers and in the regulation of gene expression. . The H19 gene is expressed exclusively on one parental allele in a phenomenon known as imprinting. H19 is only transcribed from the maternally inherited allele; the paternal H19 allele is not expressed. H19 was first named ASM (for Adult Skeletal Muscle) because of its expression in adult skeletal muscle ("ASM") in rats. H19 is also known as BWS because aberrant H19 expression can be involved in Beckwith-Wiedemann Syndrome ("BWS"), as well as Silver-Russell syndrome. Epigenetics deregulations at H19 imprinted gene in sperm have been observed associated with male infertility. Gene characterization The H19 gene contains 3 Sp1 binding sites, however these 3 sites are present in a part of the sequence that has shown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riboregulator
In molecular biology, a riboregulator is a ribonucleic acid ( RNA) that responds to a signal nucleic acid molecule by Watson-Crick base pairing. A riboregulator may respond to a signal molecule in any number of manners including, translation (or repression of translation) of the RNA into a protein, activation of a ribozyme, release of silencing RNA (siRNA), conformational change, and/or binding other nucleic acids. Riboregulators contain two canonical domains, a sensor domain and an effector domain. These domains are also found on riboswitches, but unlike riboswitches, the sensor domain only binds complementary RNA or DNA strands as opposed to small molecules. Because binding is based on base-pairing, a riboregulator can be tailored to differentiate and respond to individual genetic sequences and combinations thereof. Types of riboregulators Translational riboregulator Translational riboregulators regulate the ability of a ribosome complex to scan, assemble, and/or translate a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatocellular Carcinoma
Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults and is currently the most common cause of death in people with cirrhosis. HCC is the third leading cause of cancer-related deaths worldwide. It occurs in the setting of chronic liver inflammation, and is most closely linked to chronic viral hepatitis infection (hepatitis B or C) or exposure to toxins such as alcohol, aflatoxin, or pyrrolizidine alkaloids. Certain diseases, such as hemochromatosis and alpha 1-antitrypsin deficiency, markedly increase the risk of developing HCC. Metabolic syndrome and NASH are also increasingly recognized as risk factors for HCC. As with any cancer, the treatment and prognosis of HCC vary depending on the specifics of tumor histology, size, how far the cancer has spread, and overall health. The vast majority of HCC cases and the lowest survival rates after treatment occur in Asia and sub-Saharan Africa, in countries where hepatitis B infection is endem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choriocarcinoma
Choriocarcinoma is a malignant, trophoblastic cancer, usually of the placenta. It is characterized by early hematogenous spread to the lungs. It belongs to the malignant end of the spectrum in gestational trophoblastic disease (GTD). It is also classified as a germ cell tumor and may arise in the testis or ovary. Signs and symptoms * increased quantitative chorionic gonadotropin (the "pregnancy hormone") levels * vaginal bleeding * shortness of breath * hemoptysis (coughing up blood) * chest pain * chest X-ray shows multiple infiltrates of various shapes in both lungs * presents in males as a testicular cancer, sometimes with skin hyperpigmentation (from excess chorionic gonadotropin cross reacting with the alpha MSH receptor), gynecomastia, and weight loss (from excess chorionic gonadotropin cross reacting with the LH, FSH, and TSH receptor) in males * can present with decreased thyroid-stimulating hormone (TSH) due to hyperthyroidism. Cause Choriocarcinoma of the placenta dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cancer Induction
Carcinogenesis, also called oncogenesis or tumorigenesis, is the formation of a cancer, whereby normal cells are transformed into cancer cells. The process is characterized by changes at the cellular, genetic, and epigenetic levels and abnormal cell division. Cell division is a physiological process that occurs in almost all tissues and under a variety of circumstances. Normally, the balance between proliferation and programmed cell death, in the form of apoptosis, is maintained to ensure the integrity of tissues and organs. According to the prevailing accepted theory of carcinogenesis, the somatic mutation theory, mutations in DNA and epimutations that lead to cancer disrupt these orderly processes by interfering with the programming regulating the processes, upsetting the normal balance between proliferation and cell death. This results in uncontrolled cell division and the evolution of those cells by natural selection in the body. Only certain mutations lead to cancer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CpG Site
The CpG sites or CG sites are regions of DNA where a cytosine nucleotide is followed by a guanine nucleotide in the linear sequence of bases along its 5' → 3' direction. CpG sites occur with high frequency in genomic regions called CpG islands (or CG islands). Cytosines in CpG dinucleotides can be methylated to form 5-methylcytosines. Enzymes that add a methyl group are called DNA methyltransferases. In mammals, 70% to 80% of CpG cytosines are methylated. Methylating the cytosine within a gene can change its expression, a mechanism that is part of a larger field of science studying gene regulation that is called epigenetics. Methylated cytosines often mutate to thymines. In humans, about 70% of promoters located near the transcription start site of a gene (proximal promoters) contain a CpG island. CpG characteristics Definition ''CpG'' is shorthand for ''5'—C—phosphate—G—3' '', that is, cytosine and guanine separated by only one phosphate group; phosphate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilms' Tumor
Wilms' tumor or Wilms tumor, also known as nephroblastoma, is a cancer of the kidneys that typically occurs in children, rarely in adults.; and occurs most commonly as a renal tumor in child patients. It is named after Max Wilms, the German surgeon (1867–1918) who first described it. Approximately 650 cases are diagnosed in the U.S. annually. The majority of cases occur in children with no associated genetic syndromes; however, a minority of children with Wilms' tumor have a congenital abnormality. It is highly responsive to treatment, with about 90 percent of children being cured. Signs and symptoms Typical signs and symptoms of Wilms' tumor include the following: * a painless, palpable abdominal mass * loss of appetite * abdominal pain * fever * nausea and vomiting * blood in the urine (in about 20% of cases) * high blood pressure in some cases (especially if synchronous or metachronous bilateral kidney involvement) * Rarely as varicoceleErginel B, Vural S, Akın M, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclin-dependent Kinase Inhibitor 1C
Cyclin-dependent kinase inhibitor 1C (p57, Kip2), also known as CDKN1C, is a protein which in humans is encoded by the ''CDKN1C'' imprinted gene. Function Cyclin-dependent kinase inhibitor 1C is a tight-binding inhibitor of several G1 cyclin/Cdk complexes and a negative regulator of cell proliferation. Mutations of CDKN1C are implicated in sporadic cancers and Beckwith-Wiedemann syndrome suggesting that it is a tumor suppressor candidate. CDKN1C is a tumor suppressor human gene on chromosome 11 (11p15) and belongs to the ''cip/kip'' gene family. It encodes a cell cycle inhibitor that binds to G1 cyclin-CDK complexes. Thus p57KIP2 causes arrest of the cell cycle in G1 phase. CDKN1C was found to lead to cancer cell dormancy; its gene expression is regulated through the activity of glucocorticoid receptors (GRs) through chromatin remodelling mediated by SWI/SNF. Clinical significance A mutation of this gene may lead to loss of control over the cell cycle leading to uncont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorectal Cancer
Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Signs and symptoms may include blood in the stool, a change in bowel movements, weight loss, and fatigue. Most colorectal cancers are due to old age and lifestyle factors, with only a small number of cases due to underlying genetic disorders. Risk factors include diet, obesity, smoking, and lack of physical activity. Dietary factors that increase the risk include red meat, processed meat, and alcohol. Another risk factor is inflammatory bowel disease, which includes Crohn's disease and ulcerative colitis. Some of the inherited genetic disorders that can cause colorectal cancer include familial adenomatous polyposis and hereditary non-polyposis colon cancer; however, these represent less than 5% of cases. It typically starts as a benign tumor, often in the form of a polyp, which over time becomes cancerous. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophageal Cancer
Esophageal cancer is cancer arising from the esophagus—the food pipe that runs between the throat and the stomach. Symptoms often include difficulty in swallowing and weight loss. Other symptoms may include pain when swallowing, a hoarse voice, enlarged lymph nodes ("glands") around the collarbone, a dry cough, and possibly coughing up or vomiting blood. The two main sub-types of the disease are esophageal squamous-cell carcinoma (often abbreviated to ESCC), which is more common in the developing world, and esophageal adenocarcinoma (EAC), which is more common in the developed world. A number of less common types also occur. Squamous-cell carcinoma arises from the epithelial cells that line the esophagus. Adenocarcinoma arises from glandular cells present in the lower third of the esophagus, often where they have already transformed to intestinal cell type (a condition known as Barrett's esophagus). Causes of the squamous-cell type include tobacco, alcohol, very hot drinks, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CTCF
Transcriptional repressor CTCF also known as 11-zinc finger protein or CCCTC-binding factor is a transcription factor that in humans is encoded by the ''CTCF'' gene. CTCF is involved in many cellular processes, including transcriptional regulation, insulator activity, V(D)J recombination and regulation of chromatin architecture. Discovery CCCTC-Binding factor or CTCF was initially discovered as a negative regulator of the chicken c-myc gene. This protein was found to be binding to three regularly spaced repeats of the core sequence CCCTC and thus was named CCCTC binding factor. Function The primary role of CTCF is thought to be in regulating the 3D structure of chromatin. CTCF binds together strands of DNA, thus forming chromatin loops, and anchors DNA to cellular structures like the nuclear lamina. It also defines the boundaries between active and heterochromatic DNA. Since the 3D structure of DNA influences the regulation of genes, CTCF's activity influences the expressi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Methylation
DNA methylation is a biological process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. When located in a gene promoter, DNA methylation typically acts to repress gene transcription. In mammals, DNA methylation is essential for normal development and is associated with a number of key processes including genomic imprinting, X-chromosome inactivation, repression of transposable elements, aging, and carcinogenesis. As of 2016, two nucleobases have been found on which natural, enzymatic DNA methylation takes place: adenine and cytosine. The modified bases are N6-methyladenineD. B. Dunn, J. D. Smith: ''The occurrence of 6-methylaminopurine in deoxyribonucleic acids.'' In: ''Biochem J.'' 68(4), Apr 1958, S. 627–636. PMID 13522672. ., 5-methylcytosineB. F. Vanyushin, S. G. Tkacheva, A. N. Belozersky: ''Rare bases in animal DNA.'' In: ''Nature.'' 225, 1970, S. 948–949. PMID 4391887. and N4- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
