Search results
Results from the WOW.Com Content Network
In gliomas, a form of brain cancer, radiation therapy appears to select for stem cells, [113] [114] though it is unclear if the tumor returns to the pre-therapy proportion of cancer stem cells after therapy or if radiotherapy selects for an alteration that keeps the glioma cells in the stem cell state.
Scientist Otto Warburg, whose research activities led to the formulation of the Warburg hypothesis for explaining the root cause of cancer.. The Warburg hypothesis (/ ˈ v ɑːr b ʊər ɡ /), sometimes known as the Warburg theory of cancer, postulates that the driver of carcinogenesis (cancer formation) is insufficient cellular respiration caused by insult (damage) to mitochondria. [1]
Often, the multiple genetic changes that result in cancer may take many years to accumulate. During this time, the biological behavior of the pre-malignant cells slowly changes from the properties of normal cells to cancer-like properties. Pre-malignant tissue can have a distinctive appearance under the microscope.
Among solid tumors, the clinical significance of the proliferation index on breast cancer has been extensively studied. Mitotic counting has also been shown in multiple studies to have prognostic value in breast cancer, where a lower count of mitotic cells correlates with a more favorable outcome, and thus has been incorporated into part of the ...
Cancer cells have been observed to divide in multiple directions by evading the spindle assembly checkpoint resulting in multipolar mitoses. [78] The multipolar metaphase-anaphase transition occurs through an incomplete separase cycle that results in frequent nondisjunction events which amplify aneuploidy in cancer cells.
Bypassing the checkpoint leads to the rapid accumulation of deleterious mutations, which is thought to drive the cancerous cells into apoptosis. Conversely, attempts to prolong the G2/M arrest have also been shown to enhance the cytotoxicity of drugs like doxorubicin. These approaches remain in clinical and pre-clinical phases of research. [17]
In cancer cells, it has been observed that the formation of the spindles comes before when compared to the chromosomes. Because the prophase stage is brief, metaphase begins earlier than in normal cells. Chromosomes unable to reach the metaphase plate are stranded behind. These chromosomes still have asters attached to them and when met with ...
In cancer cells "global hypomethylation" due to disruption in DNA methyltransferases (DNMTs) may promote mitotic recombination and chromosome rearrangement, ultimately resulting in aneuploidy when the chromosomes fail to separate properly during mitosis.