Cell Cycle and Cancer Vocabulary

Flashcards on Cell Cycle and Cancer

Mitosis

A process that allows the generation of new identical daughter cells. It is a precise process of nuclear division that ensures each of two daughter cells receives a diploid complement of chromosomes identical with the diploid complement of the parent cell.

Cytokinesis

The process in which the cell itself divides to yield two daughter cells, usually accompanying mitosis.

Cell Cycle

Represents the different stages cells can be in and is under genetic control. It is a true cycle and not reversible.

Growth Factors

Necessary to initiate cell division in animal tissues during the transition from G1 to S phase. They bind to receptors, leading to a conformational change and intracellular response.

Cyclin-Dependent Kinases (CDKs)

Family of kinases that regulate the transition through stages of the cell cycle; they only function when associated with cyclins.

Cyclins

Essential for starting the cell cycle, and their expression is often restricted to specific phases within the cell cycle.

Retinoblastoma (RB) Protein

Controls the initiation of DNA synthesis by maintaining cells at the G1 restriction point by binding to the transcription factor E2F until the cell has attained proper size.

Cell Cycle Checkpoints

Maintain the correct order of steps as the cell cycle progresses by causing the cell cycle to pause while defects are corrected or repaired; allow damaged cells to repair or self-destruct.

DNA Damage Checkpoint

Arrests the cell cycle when DNA is damaged or replication is not completed. In animal cells, it acts at three stages: G1/S transition, S period, and G2/M boundary.

P53 Transcription Factor

A key player in the DNA damage checkpoints; it is activated by DNA damage and other stress factors, leading to transcription of genes involved in cell cycle arrest, DNA repair, or apoptosis.

Apoptosis

Programmed cell death, which can be induced by p53 in an extreme case of DNA damage.

Spindle Checkpoint

Monitors assembly of the spindle and its attachment to kinetochores, preventing separation of sister chromatids if there is incorrect attachment.

Kinetochore

The spindle-fiber attachment site on the chromosome.

Cancer

Cancer cells show uncontrolled growth as a result of mutations in a relatively small number of genes.

Proto-Oncogene

Normal (wildtype) forms of genes that aid in cell proliferation in healthy tissues.

Oncogene

Gain-of-function mutations associated with cancer progression; function by enhancing the expression of genes that promote cell proliferation or inhibit apoptosis.

Ras Protein

Normal Ras is inactive until it becomes activated by the binding of growth factors to their receptors.

Tumor Suppressor Genes

Negatively control cell proliferation or activate the apoptotic pathway; loss-of-function mutations contribute to cancer progression.

Bax

A protein that promotes apoptosis and is normally kept inactive in healthy cells by Bcl2.

Retinoblastoma

Mutations in the RB gene can cause retinal cancer.

Acute Leukemias

Malignant diseases of the bone marrow, spleen, and lymph nodes associated with uncontrolled proliferation of leukocytes and their precursors in the bone marrow.

Promoter Fusion

The coding region for a gene that encodes a transcription factor is translocated near an enhancer for an immunoglobulin heavy-chain gene or a T-cell receptor gene.

Gene Fusion

The translocation breakpoints occur in introns of genes for transcription factors in two different chromosomes, resulting in a fusion gene called a chimeric gene.

Gene Fusion Example

Translocation creates chimeric protein with domains of two different transcription factors.