Suppose You Are Studying Tumor Heterogeneity in a Certain Type

question 32

Short Answer

Suppose you are studying tumor heterogeneity in a certain type of melanoma. You have used fluorescence-activated cell sorting (FACS) to specifically isolate those melanoma tumor cells that either do (first category) or do not (second category) express a specific marker present in normal stem cells in the tissue of origin (i.e. the melanocyte stem cells). You implant the same number of cells from each of these categories into severely immunodeficient mice and compare the tumor-formation efficiencies after several weeks, which turn out to be significantly higher for the first category. You then analyze the new tumors using FACS, and find out that the majority of the cells in the tumors that originated from the first category of cells harbor the stem-cell marker, whereas the majority of the cells in the tumors that originated from the second cell category lack the marker, just like their respective founder cells. Do these observations support the existence of cancer stem cells? Write down Yes or No as your answer.

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Definitions:

Exam Cheating

The act of using unauthorized means or methods to achieve higher grades or scores in educational assessments.

Defective Personalities

A pejorative term potentially referring to individuals who exhibit personality traits or behaviors considered abnormal or dysfunctional within their cultural context; however, it is not a widely accepted or respectful term in psychology.

Diffusion of Responsibility

A psychological phenomenon where individuals are less likely to take action or feel a sense of responsibility in the presence of others, often cited in explaining bystander inaction.

Cognitive Model

A psychological framework that emphasizes the importance of an individual's thoughts in determining their feelings and behaviors.