UROTHELIAL DIFFERENTIATION: RATIONALE: The main goal of this proposal is to investigate urothelial differentiation. The rationale of this proposal is that reciprocal cell-cell signaling between bladder epithelium, and stroma is necessary for the maintenance of normal urothelium. We hypothesize that normal homeostatic interactions between the bladder epithelium and the underlying stroma are critical for maintaining normal bladder function. A key aspect of normal bladder development is the differentiation of smooth muscle cells from undifferentiated bladder mesenchyme. Likewise reciprocal interactions between the mesenchyme and subsequently the stroma maintain the urothelial cell phenotype. Simple, normal bladder stroma is necessary for normal urothelial function. Conversely, abnormal epithelial-stromal interactions leads to changes of the urothelial phenotype, atypia or cancer. Smooth muscle differentiation is a gradual process during normal bladder development, and characteristic smooth muscle differentiation markers are expressed in a temporally specific sequence. Likewise, urothelial cell differentiation can be documented by a progressive expression of various cytokeratins and uroplakins.
In specific aim #1 we propose that the urothelial phenotype can de-differentiate under the influence of """"""""foreign"""""""" stroma. Conversely, in specific aim #2 we propose that epithelial cells under the influence of the appropriate stroma can differentiate into urothelium.
Specific aim #3 addresses the contribution of specific growth factors as the mechanism of urothelial proliferation and differentiation. The strategy behind specific aim #3 is to use growth factor knock-out and growth factor receptor knock-out animals as the basis of tissue recombination experiments. The long-term objective of this research is to develop effective strategies for inducing and maintaining urothelial differentiation for urinary tract rehabilitation. Understanding and controlling urothelial differentiation may reduce the complications in patients with intestinal augments. Furthermore, we propose that abnormal epithelial-stroma signaling that occurs when intestinal segments are placed in contact with the bladder may lead to cellular changes such as atypia or even cancer.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK057246-04
Application #
6524581
Study Section
Special Emphasis Panel (ZDK1-GRB-4 (O1))
Program Officer
Mullins, Christopher V
Project Start
1999-09-30
Project End
2004-08-31
Budget Start
2002-09-01
Budget End
2003-08-31
Support Year
4
Fiscal Year
2002
Total Cost
$221,250
Indirect Cost
Name
University of California San Francisco
Department
Urology
Type
Schools of Medicine
DUNS #
073133571
City
San Francisco
State
CA
Country
United States
Zip Code
94143
Li, Jiang; Shiroyanagi, Yoshiyuki; Lin, Guiting et al. (2006) Serum response factor, its cofactors, and epithelial-mesenchymal signaling in urinary bladder smooth muscle formation. Differentiation 74:30-9
Staack, Andrea; Hayward, Simon W; Baskin, Laurence S et al. (2005) Molecular, cellular and developmental biology of urothelium as a basis of bladder regeneration. Differentiation 73:121-33
Cunha, Gerald R; Baskin, Laurence (2004) Development of the penile urethra. Adv Exp Med Biol 545:87-102
Yucel, Selcuk; De Souza Jr, Antonio; Baskin, Laurence S (2004) Neuroanatomy of the human female lower urogenital tract. J Urol 172:191-5
Yucel, Selcuk; Baskin, Laurence S (2003) Identification of communicating branches among the dorsal, perineal and cavernous nerves of the penis. J Urol 170:153-8
Yucel, S; Baskin, L S (2003) Neuroanatomy of the male urethra and perineum. BJU Int 92:624-30
Yamada, Gen; Satoh, Yoshihiko; Baskin, Laurence S et al. (2003) Cellular and molecular mechanisms of development of the external genitalia. Differentiation 71:445-60
Baskin, Laurence S (2002) Anatomical studies of the fetal genitalia: surgical reconstructive implications. Adv Exp Med Biol 511:239-49
Baskin, L S; Erol, A; Jegatheesan, P et al. (2001) Urethral seam formation and hypospadias. Cell Tissue Res 305:379-87
Baskin, L; DiSandro, M; Li, Y et al. (2001) Mesenchymal-epithelial interactions in bladder smooth muscle development: effects of the local tissue environment. J Urol 165:1283-8

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