A 62-year-old man comes to the office due to an enlarging mole on his left forearm. The patient works as a farmer and has a significant amount of sun exposure daily. On examination, he has a black-brown macular lesion on the dorsum of his right forearm measuring approximately 1 cm in diameter with an irregular border. Excisional biopsy is performed and histopathology reveals malignant melanoma. Immunohistochemical analysis indicates that the malignant cells have decreased integrin expression. These cells are most likely to exhibit poor adhesion to which of the following components of the extracellular matrix?

Question

A 62-year-old man comes to the office due to an enlarging mole on his left forearm.  The patient works as a farmer and has a significant amount of sun exposure daily. On examination, he has a black-brown macular lesion on the dorsum of his right forearm measuring approximately 1 cm in diameter with an irregular border.  Excisional biopsy is performed and histopathology reveals malignant melanoma.  Immunohistochemical analysis indicates that the malignant cells have decreased integrin expression.  These cells are most likely to exhibit poor adhesion to which of the following components of the extracellular matrix?

Quizplus · Accepted Answer

Eductional Objective: Adhesion of cells to the extracellular matrix involves integrin-mediated binding to fibronectin, collagen, and laminin.  Differential expression of integrin subtypes affects adhesion properties of individual cells, and has been found to correlate with malignant behavior in a number of tumors.

A 62-Year-Old Man Comes to the Office Due to an Enlarging