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Related to malignant cell: cancer cell
malignant cellA cell that has undergone malignant transformation—i.e., is in a state of permanent proliferation and capable of metastasis.
Phenotypic changes in malignant cells
• Decreased intercellular adhesion;
• Electrical repulsion (due to a loss of anchorage dependence);
• Decreased intracellular K+ and Ca2+;
• Loss of response to control by the usual cytokines and mitogens;
• Ectopic hormone production;
• Use of aberrant metabolic pathways;
• Biochemical convergence—cells lose features of differentiation and organ-specific features (e.g., microvilli);
• Desmosomes, intermediate filaments.
• Nucleolar margination (a sign of rapid growth);
• Cytologic atypia;
• Nuclear irregularity;
• High nuclear:cytoplasmic ratio;
• Swelling of mitochondria and flooding of the mitochondrial matrix.
• Altered growth parameters and cell behaviour;
• Cell surface alterations;
• Loss of actin myofilaments;
• Increased transforming growth factor release;
• Increased protease secretion;
• Altered gene transcription;
• Immortalisation of cells.