Cancer cell uncontrolled proliferation

We see some similarities between the major life processes in plants (growth and differentiation) and the major life processes in animals and humans (proliferation and differentiation). We expect in future to relate this concept to animal production and to human health, to be able to cross the bridge from soil to plant to animal and finally human health. For example, the development in medicine of differentiation therapy in which vitamin A-derivates are used to treat human cancer cells in vitro (De Luca el al., 1995). Cancer is defined by too much uncontrolled growth of cells without enough differentiation. Using treatment with vitamin A-derivatives - a product of differentiation processes in the plant - undifferentiated cancer cells change into differentiated more healthy ones. 

Since the uncontrolled proliferation is a peculiar characteristic of cancer cells, the proteins involved in DNA replication are attractive targets in modem chemotherapy. Several preclinical works showed in colorectal tumors, higher... 

Cancer is a disease characterised by uncontrolled proliferation of cells that produces a tumour, from which the cells can invade local tissues and then spread to give rise to metastases. Cancers are classified into three groups carcinomas, sarcomas and leukaemias/lymphomas. Carcinomas, the most common, arise in epithelial cells, sarcomas in connective tissue (e.g. bone, cartilage) and leukaemias and lymphomas from white blood cells. 

Posner and coworkers have prepared a series of semi-synthetic and synthetic ether and ester-linked dimers that were found to have potent anti-proliferative and antitumour activities in vitro162. Some of these trioxane dimers were found to be as antiproliferative as calcitriol, the hormonally active form of vitamin D, which is used to treat psoriasis, a skin disorder characterized by uncontrolled cell proliferation. Of the semi synthetic dimers, a polyethylene glycol-linked dimer 107, with /3-stereochemistry at both of the lactol acetal positions, was found to be very anti-proliferative and showed activity against leukaemia and colon cancer cell lines in the National Cancer Institute (NCI), USA 60-cell line assay. 

An important characteristic of cancer cells is their uncontrolled proliferation. They don t respond to the normal signals from adjacent cells that indicate that cell division should stop. Cancer cells also differ dramatically from those present in warts and other benign tumors and in psoriasis. These conditions also result in excessive proliferation of cells and partial derangement of normal regulatory processes. 

The Phototherapy of Cancer a Mode of Treatment Still at the Research Stage. Cancer is the uncontrolled proliferation of cells which build up into tumours. Treatments rely on the elimination of diseased cells, through surgery, through the effects of ionizing radiation or through chemicals. 

Breast cancer cells, like most other cancer cells, are exposed to excess growth factors which activate the Ras/MAPK pathway, promoting cellular proliferation. Consequently, ERs are phosphorylated, increasing their transcriptional activity. The uncontrolled transcriptional activity of phosphorylated ERs is implicated in breast cancer, the most common tumour in females. Downregulation of immediate early genes, responsible for cellular proliferation, is one of the objectives of breast cancer therapy (see Part 4). 

More CKIs have been identified. Each of these proteins is a potential regulator of the cell cycle. Since malfunctions in the cydin-Cdk control of the cell cycle lead to uncontrolled proliferation and may cause cancer, interest in the development of effective CKIs is great. 

A mass of cells resulting from the uncontrolled proliferation of cancer cells... 

The basic differences between cancer cells and normal edh are uncontrolled cell proliferation, decreased cellular differentiation, ability to invade surrounding tissue, and ability ip establish new growth at ectopic sites (metastasis). Conuaiy to popular belief, not all tumor cells proliferate rapidly. Plv-liferation rates vary widely with the cell type. Thus, lymphomas and normal intestinal mucosa both proliferate fasui than. solid tumors. Acute leukemia cells actually prolifemc more slowly than the corresponding precursors in normal bone marrow. 

Uncontrolled cell division, the hallmark of cancer, is relatively inelScient at inflicting morbidity. Single tumors are very often amenable to complete surgical removal. It is the metastatic spread of tumors that renders surgical removal ineffective. Successful metastatic spread of a cell to a new site requires activities that have litde to do with uncontrolled proliferation. However, once at a new site, the tumor cell must divide, in order to create a secondary tumor with adverse consequences for the host. Thus, cell division is at the foundation of tumor formation at the initial site and at new secondary sites. It is for this reason that cell division provides an important target for the treatment of cancer. 

By definition, cancer cells proliferate in an uncontrolled manner. This lack of control usually arises from an accumulation of mutations in the genes of those proteins that have roles in cell proliferation. The mutant proteins either may have lost their normal frmctions or are locked into permanently active states. 

Cancer cells proliferate in an uncontrolled manner. How might this be linked to defects in signaling pathways ... 

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