HSC 4555 Lecture Notes - Lecture 7: Cervical Cancer, Carcinogen, Radiation Therapy
Document Summary
Neoplastic cells have an altered expression of cellular genes that normally regulate cell proliferation and differentiation that leads to uncontrolled cellular growth (pg. Benign cells more closely resemble their tissue type of origin, grow slowly, have little vascularity, rarely have necrotic areas, and often retain functions similar to those of the tissue of origin. Malignant cells often grow rapidly and spread to distant sites, frequently have necrotic tissue, initiate vessel growth in the tumor, and are dysfunctional (pgs. Overexpression of proto-oncogenes can lead to abnormal cellular proliferation through increased coding for components of the cellular growth-activating pathways: growth factors, receptors, cytoplasmic signaling molecules and nuclear transcription factors (pgs. Tumor suppressor genes normally inhibit cell proliferation, thus underexpression of these genes would lead to less regulation of cellular proliferation, or uninhibited cellular proliferation (pgs. Tumor grading, or identifying the histological characterization, is used to determine the malignancy potential. Generally, tumors with a higher malignancy potential are treated more aggressively.