Bio422 to the surface of endothelial cells and cells

Bio422            Take
home questions. 


note that References for your sources need to be included in the answers.

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1.      Find a gene that is either up-regulated or
down-regulated in either Intravasation or Extravasation and explain how its
regulation affects that process.  (4)

or COX2, promotes extravasation
in the lung (Bos 2009). COX2 has been researched and found to enable “extravasation
of breast cancer cells across the blood-brain barrier” (Lee 2011). In order for this occur, COX2
is induced from human brain endothelial cells, and this plays a crucial role in
the transmigration (Lee 2011). Furthermore, COX2 expression in primary
tumors enhances cancer cells for extravasation through the “non-fenestrated” capillaries
of the brain and lungs. In addition, the up-regulation
of COX2, which is involved in both the “vascular and extracellular matrix
remodeling,” promotes extravasation and metastasis (Labelle 2012). Overall,
COX2 plays a role in up-regulation in extravasation when dealing with the lungs
and the brain.



Bos PD, Zhang
XH, Nadal C, Shu W, Gomis RR, Nguyen DX, Minn
AJ, van de Vijver MJ, Gerald WL, Foekens JA, Massagué J.

(2009). “Genes that mediate breast cancer metastasis to the brain.” Nature, 459(7249):1005-9. doi:
10.1038/nature08021. Epub 2009 May 6.

Labelle, M., &
Hynes, R. O. (2012). “The initial hours of metastasis: the importance of
cooperative host-tumor cell interactions during hematogenous dissemination.” Cancer
Discovery, 2(12), 1091–1099.

KY, Kim YJ, Yoo H, Lee SH, Park JB, Kim HJ. (2011).

Human brain endothelial cell-derived COX-2 facilitates extravasation of breast
cancer cells across the blood-brain barrier. Anticancer Res, 31(12):4307-13.




2.      Please discuss the structure and functions of
ICAM-1 and MUC-1.  (4)

            ICAM-1, or Intercellular Adhesion
Molecule 1, is known as a protein-coding gene that encodes a cell surface
glycoprotein. ICAM-1 can bind to integrins “CD11a / CD18 or CD11b / CD18,” and
can be manipulated by “Rhinovirus as a receptor” (ICAM1 2017). For ICAM-1’s structure, it is an “immunoglobulin-like protein”
that is expressed in soluble form and is capable of being membrane-bound to the
surface of endothelial cells and cells used in the immune response (Pietruczuk 2014). In addition, ICAM-1 plays a vital role in the “adhesion
and migration of leukocytes to the sites of inflammation” (Pietruczuk

            MUC-1, or Mucin 1, is also a protein-coding
gene that encodes a membrane-bound protein. Mucins are known to be “O-glycosylated
proteins” that aid in the formation of protective mucous barriers found on
epithelial surfaces (MUC1 2017). MUC1 is a “large, trans-membrane mucin
glycoprotein” that is expressed at the “apical surface” and will line the
mucosal surfaces of many different tissues that include lung, breast stomach
and pancreas (Brayman 2004). What these proteins do is play a role in
intracellular signaling and are typically used as “a diagnostic marker for
metastatic progression” (Horm 2013). 

            When looking at ICAM-1 and MUC-1
together, it has been studied that the MUC1 peptide core facilitates firm adhesion of tumor
cells to adjacent cells from binding to ICAM-1. From research, there is
increasing evidence that MUC-1 is involved in signaling. ICAM-1 is currently
the only known direct ligand of the MUC1 extracellular domain (Rhan 2009). 




Brayman, M.,
Thathiah, A., Carson, D. D. (2004). MUC1: A multifunctional cell surface
component of reproductive tissue epithelia. Reproductive Biology and
Endocrinology?: RB, 2, 4.

TM, Schroeder JA. (2013). (2013). “MUC1 and metastatic cancer: expression,
function and therapeutic targeting.” Cell
Adh Migr, 7(2):187-98. doi: 10.4161/cam.23131.

Gene(Protein Coding). (n.d.). Retrieved December 03, 2017, from

Gene(Protein Coding). (n.d.). Retrieved December 03, 2017, from

M, Pietruczuk A, Pancewicz S, Hermanowska-Szpakowicz T. (2014).

“ICAM-1: structure, biological role and clinical significance.” Pol Merkur Lekarski, 17(101): 507-11.

JJ, Shen Q, Mah BK, Hugh JC. (2009). “MUC1 Initiates a
Calcium Signal after Ligation by Intercellular Adhesion Molecule-1.” J. Biol. Chem, 279: 29386-. doi:10.1074/jbc.C400010200