Transcript Overexpression of Serine Proteases in Ovarian Cancer

Overexpression of Serine
Proteases in Ovarian Cancer
Figure 1. Female reproductive organs [Campbell, 1998].
Shelley Campeau
Cellular and Developmental Biology Major
University of California at Santa Barbara
Topics
• Overview of ovarian cancer
• Role of serine proteases in ovarian
tumor growth
• Two experiments showing serine
protease expression in ovarian
cancer
Why Study Serine Proteases?
 Allows growth and spread of ovarian cancer.
 Produced early in tumor formation and can
be detected early.
 Inhibiting serine proteases may possibly
stop ovarian tumor formation.
Overview: Ovarian Cancer
Cancer that forms in the cells surrounding
the ovaries.
Figure 2. Stains of a normal ovary and an ovarian
tumor for serine proteases [Underwood, 2000].
5 year survival rate for women with ovarian cancer is below 50%
How Ovarian Cancer Invades
Initiates development around ovaries.
Tumor cells can break off and spread
to other sites.
Secondary tumors can form.
Figure 3. Metastasis and the spreading
of cancer [McKinnell, 1998].
Role of Serine Proteases
What are they?
Enzymes involved in the breakdown of proteins in
extracellular compartments.
Function in tumor growth
Breakdown extracellular components surrounding ovaries

Allows tumor cells to rapidly divide

Tumor cells can break off and travel to different locations to spread cancer
Serine Proteases:
Potential for Diagnosis and Treatment
If:
Normal
cells
+
Serine
Proteases

Tumor cell growth
and progression of
cancer.

PREVENT
TUMOR
GROWTH!
Then:
Normal
cells
+
Inhibited
Serine
Proteases
Experiment 1:
Polymerase Chain Reaction (PCR)
Process



Amplify serine protease gene from ovarian tumor and
normal ovary tissue.
Separate products obtained from experiment based on size.
Look for band size of serine protease expression: 180bp
Figure 4. PCR for a serine protease.
Normal ovary in left lane, ovarian tumor
in right lane [Underwood, 2000].
Results
Band size of serine protease expression is found in
ovarian cancer tissue but not in normal ovary tissue.
Experiment 2:
Northern Blot Analyses
Process:
 Separates RNA fragments of a tissue sample based on size.
 A probe for a specific region of RNA hybridizes to the
corresponding fragment.
TADG
Testisin
Figure 5. Northern blot analyses
of serine proteases: TADG
[Underwood, 2000] and Testisin
[Shigemasa,2000].
Results:
Bands found in ovarian cancer tissue and not in significant
levels in normal ovary tissue.
Conclusion
 Serine proteases aid in the
development of ovarian cancer.
 Used as a tumor marker, serine
proteases may be used to help identify
cancer before it is too late.