Quiz #1 Epidemiological Concepts, Epigenetics, and Cancer Biology

This flashcard set covers foundational concepts in epidemiology, epigenetics, and the biological mechanisms of cancer development and progression, including pediatric-specific information.

Relative Risk (RR)

The ratio of the incidence (or rate) of a disease among an exposed group compared to an unexposed group, represented by the formula $RR = \frac{\text{Incidence in Exposed}}{\text{Incidence in Non-exposed}}$

Empirical Risks

Risks calculated from direct observation in populations and families, commonly used for multifactorial conditions like type 2 diabetes and neural tube defects.

Housekeeping Genes

Genes consistently expressed in almost all cells that provide fundamental functions, such as ribosomal proteins and metabolic enzymes.

miRNAs

Short, noncoding RNA molecules primarily derived from introns of protein-coding genes that regulate gene expression post-transcriptionally.

Hypomethylation of oncogenes

An epigenetic change that can lead to the overexpression of oncogenes, facilitating the transition from benign to malignant tumors.

Hypermethylation of tumor-suppressor genes

An epigenetic modification that can silence the protective function of tumor-suppressor genes.

ras Gene

A gene that, when mutated, allows continuous cell growth by locking signaling pathways in an active state.

Proto-Oncogenes

Normal genes involved in cell growth that become oncogenes (cancer-promoting) when mutated or overexpressed.

Pleomorphism

A characteristic of malignant tumor cells where they vary significantly in size and shape.

Angiogenesis

The process by which cancer cells secrete angiogenic factors, such as $VEGF$, to stimulate new blood vessel growth.

Telomerase

An enzyme that cancer cells often reactivate to maintain telomere length, enabling repeated divisions beyond normal limits.

Epithelial-Mesenchymal Transition (EMT)

A process where cancer cells lose cell–cell adhesion and gain migratory capacity and resistance to apoptosis, which is key for metastasis.

Staging of Cancer

A classification system where Stage 1 is confined to the organ of origin, Stage 2 is locally invasive, Stage 3 involves regional structures (e.g., lymph nodes), and Stage 4 involves distant metastases.

Human papillomavirus (HPV)

A virus, particularly strains 16 and 18, that is a major cause of cervical cancer.

Trisomy 21 (Down syndrome)

A genetic condition associated with an increased risk of acute leukemia, particularly acute lymphoblastic leukemia, in pediatric patients.

Mesodermal germ layer

The embryonic tissue layer from which many childhood cancers, including bone, blood, and muscle tumors, originate.

Wilms tumor

Also known as nephroblastoma, it is a common renal tumor found in young children.