Question

1a.

Which of the following would tend to stimulate metastasis? Select all that apply.

		production of proteases that degrade structural proteins
		activation of rho-GTPases
		production of E-cadherin
		reduced DNA polymerase activity

1b.

You observe a tumor that is producing VEGF and FGF but not displaying angiogenesis. Which of the following could explain this observation? Select all that apply.

		Angiostatin is present in high concentrations
		There are no blood vessels nearby enough
		The cancer is metastatic
		Angiogenesis inhibitors are present in concentrations that are too low

1c. You have cultured a type of sea urchin cell with a generation time of 4 hours. Under the microscope, you observe that 4.7% of your cells are undergoing mitosis.
What is the mitotic index?
What is the length of M phase?

1d. Fill in the blanks: Mutations can cause cancer when they change a(n) [blank] into [blank] , or when they disrupt the function of a(n) [blank].

Answer 1

Answer 1a:activation of rho-GTPases

Rho GTPases are, known to function in the regulation of reorganization of actin and they have been found to function in cellular processes like cell migration, wound healing, cell adhesion, cell polarity, membrane trafficking and cytokinesis. They are seen to effect more than 100 different cellular targets regulating different cellular pathways and effecting cellular functions. Rho-GTPase have been seen to have the ability to regulate cytoskeletal dynamics, cell adhesion and also cancer cell migration.

Answer 1b:Angiostatin is present in high concentrations

In a number of studies angiostatin has shown to effect endothelial cell migration. Angiostatin has also been found to inhibit migration process in primary human microvascular endothelial cells and has been found to effect vascular formation in the embryoid body model by inhibiting fibroblast growth factor (FGF)-, and vascular endothelial growth factor (VEGF

Answer 1d: Mutation can cause cancer when they change a Proto-oncogene into oncogene or when they disrupt the function of a tumor suppressor gene.

Oncogene is a cancer causing gene which can get activated due to mutation and tumor suppressor genes are cancer suppressing genes disruption in its function can also lead to cancer.