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Mouse Models Of Breast Cancer Metastasis
Breast cancer metastatic mouse models are experimental approaches in which mice are Genetic engineering, genetically manipulated to develop a mammary tumor leading to distant focal lesions of mammary epithelium created by metastasis. Mammary cancers in mice can be caused by genetic mutations that have been identified in human cancer. This means models can be generated based upon molecular lesions consistent with the human disease. Breast cancer metastasis Metastasis is a process of Cell migration, migration of Neoplasms, tumour cells from the primary cancer site to a distant location where the cancer cells form secondary tumors. Metastatic breast cancer represents the most devastating attribute of cancer and it is considered an advanced-stage event. Human breast cancer metastasizes to multiple distant organs such as the brain, lungs, bones and liver. Genetic diversity between primary and metastatic tumor The classical theory developed in the early 70's anticipated that metastasis i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Engineering
Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of Genetic engineering techniques, technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by Artificial gene synthesis, artificially synthesising the DNA. A Vector (molecular biology), construct is usually created and used to insert this DNA into the host organism. The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the Lambda phage, lambda virus. As well as inserting genes, the process can be used to remove, or "Gene knockout, knock out", genes. The new DNA can either be inserted randomly or Gene targeting, targeted to a spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colonization (biology)
Colonisation or colonization is the spread and development of an organism in a new area or habitat. Colonization comprises the physical arrival of a species in a new area, but also its successful establishment within the local community. In ecology, it is represented by the symbol ''λ'' (lowercase lambda) to denote the long-term intrinsic growth rate of a population. Surrounding theories and applicable process have been introduced below. These include dispersal, colonisation-competition trade off and prominent examples that have been previously studied. One classic scientific model in biogeography posits that a species must continue to colonize new areas through its life cycle (called a ''taxon cycle'') in order to persist. Accordingly, colonisation and extinction are key components of island biogeography, a theory that has many applications in ecology, such as metapopulations. Another factor included in this scientific model is the competition-colonisation trade off. This idea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oncogenes
An oncogene is a gene that has the potential to cause cancer. In tumor cells, these genes are often mutated, or expressed at high levels.Kimball's Biology Pages. "Oncogenes" Free full text Most normal cells undergo a preprogrammed rapid cell death () if critical functions are altered and then malfunction. Activated oncogenes can cause those cells designated for apoptosis to survive and proliferate instead. Most oncogenes began as proto-oncogenes: normal genes involved in cell growth and proliferation or inhibition of apoptosis. If, through mutation, normal genes promoting cellular growth are up-regulated (gain-of-function mutation), they predispose the cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptation
In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the population during that process. Thirdly, it is a phenotypic trait or adaptive trait, with a functional role in each individual organism, that is maintained and has evolved through natural selection. Historically, adaptation has been described from the time of the ancient Greek philosophers such as Empedocles and Aristotle. In 18th and 19th-century natural theology, adaptation was taken as evidence for the existence of a deity. Charles Darwin and Alfred Russel Wallace proposed instead that it was explained by natural selection. Adaptation is related to biological fitness, which governs the rate of evolution as measured by changes in allele frequencies. Often, two or more species co-adapt and co-evolve as they develop adaptations tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lethality
Lethality (also called deadliness or perniciousness) is how capable something is of causing death. Most often it is used when referring to diseases, chemical weapons, biological weapons, or their toxic chemical components. The use of this term denotes the ability of these weapons to kill, but also the possibility that they may not kill. Reasons for the lethality of a weapon to be inconsistent, or expressed by percentage, can be as varied as minimized exposure to the weapon, previous exposure to the weapon minimizing susceptibility, degradation of the weapon over time and/or distance, and incorrect deployment of a multi-component weapon. This term can also refer to the after-effects of weapon use, such as nuclear fallout, which has highest lethality nearest the deployment site, and in proportion to the subject's size and nature; e.g. a child or small animal. Lethality can also refer to the after-effects of a major chemical or oil/gas process loss of containment, causing fire, ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeostasis
In biology, homeostasis (British English, British also homoeostasis; ) is the state of steady internal physics, physical and chemistry, chemical conditions maintained by organism, living systems. This is the condition of optimal functioning for the organism and includes many variables, such as body temperature and fluid balance, being kept within certain pre-set limits (homeostatic range). Other variables include the pH of extracellular fluid, the concentrations of sodium, potassium, and calcium ions, as well as the blood sugar level, and these need to be regulated despite changes in the environment, diet, or level of activity. Each of these variables is controlled by one or more regulators or homeostatic mechanisms, which together maintain life. Homeostasis is brought about by a natural resistance to change when already in optimal conditions, and equilibrium is maintained by many regulatory mechanisms; it is thought to be the central motivation for all organic action. All home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. 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 non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotypes
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological properties, and its behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code (its genotype) and the influence of environmental factors. Both factors may interact, further affecting the phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and again in his 1982 book '' The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as caddisfly larva cases and beaver dams as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoplasm
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists in growing abnormally, even if the original trigger is removed. This abnormal growth usually forms a mass, which may be called a tumour or tumor.'' ICD-10 classifies neoplasms into four main groups: benign neoplasms, in situ neoplasms, malignant neoplasms, and neoplasms of uncertain or unknown behavior. Malignant neoplasms are also simply known as cancers and are the focus of oncology. Prior to the abnormal growth of tissue, such as neoplasia, cells often undergo an abnormal pattern of growth, such as metaplasia or dysplasia. However, metaplasia or dysplasia does not always progress to neoplasia and can occur in other conditions as well. The word neoplasm is from Ancient Greek 'new' and 'formation, creation'. Types A neoplasm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clone (cell Biology)
A clone is a group of ''identical'' cells that share a ''common ancestry'', meaning they are derived from the same cell. Clonality implies the state of a cell or a substance being derived from one source or the other. Thus there are terms like ''polyclonal''—derived from many clones; ''oligoclonal''—derived from a few clones; and ''monoclonal''—derived from one clone. These terms are most commonly used in context of antibodies or immunocytes. Contexts This concept of clone assumes importance as all the cells that form a clone share common ancestry, which has a very significant consequence: shared genotype. # One of the most prominent usage is in describing a clone of B cells. The B cells in the body have two important phenotypes (functional forms)—the antibody secreting, terminally differentiated (that is, they cannot divide further) plasma cells, and the memory and the naive cells—both of which retain their proliferative potential. # Another important area where o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcinomas
Carcinoma is a malignancy that develops from epithelial cells. Specifically, a carcinoma is a cancer that begins in a tissue that lines the inner or outer surfaces of the body, and that arises from cells originating in the endodermal, mesodermal or ectodermal germ layer during embryogenesis. Carcinomas occur when the DNA of a cell is damaged or altered and the cell begins to grow uncontrollably and becomes malignant. It is from the (itself derived from meaning ''crab''). Classification As of 2004, no simple and comprehensive classification system has been devised and accepted within the scientific community. Traditionally, however, malignancies have generally been classified into various types using a combination of criteria, including: The cell type from which they start; specifically: * Epithelial cells ⇨ carcinoma * Non-hematopoietic mesenchymal cells ⇨ sarcoma * Hematopoietic cells ** Bone marrow–derived cells that normally mature in the bloodstream ⇨ leukemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
