2010 Annual Report - Cancer Research Center

Current Research
TargeTeD Ba c T e r i a l ca n c e r Th e r a p y ma T u r e s (2010 a n D B e y O n D)
Cancer research focuses on the three requirements for treating cancer: 1) Early Detection. Cancer detected
early is treatable and almost always results in complete recovery. 2) Targeted Treatment. If you can target a
cancer-killing drug therapy to the cancer cells but spare normal cells, you can administer powerful, effective
drugs at much lower dosages, killing the cancer while minimizing or eliminating unwanted side effects. 3)
New, Effective Chemotherapy. Although different types of cancer result in the same problem (uncontrollably
growing tumors), each cancer type is different and reacts differently to anti-cancer drugs.
In 2010, an estimated 217,730 men will be newly diagnosed with prostate cancer in the United States and
about 32,050 men will die from the disease. Prostate
cancer is associated with aging and occurs in a latent
or clinical form in 30-40% of men by age 40-50. Prostate
cancer cases increase substantially in men over 50
years of age. While hormone chemotherapy is often effective
during the initial stages of cancer development,
most men develop hormone-resistant cancer within
two years after treatment of the clinical disease and
metastatic lesions are difficult to cure. Therefore, new
approaches are desperately needed.
Building on the hard work and success of the last six
years, in 2010 we performed experiments to test the
effects of our non-toxic bacterial cancer targeting (BCT)
therapy on the immune systems of our TRAMP mice.
These experiments gave groups of prostate tumorbearing
mice a range of Salmonella doses weekly over
a period of 12 weeks and measured the effects of BCT
therapy up to 24 hours after each dose. None of the
mice dosed at our therapeutic levels died during this
study and immunological tests for inflammation after
repeated doses were negative, demonstrating that our
BCT therapy could be given repeatedly to immunocompetent
mouse models without causing an immune
reaction. Confirmation that our BCT therapy does not
cause an immune reaction after repeated doses is an
important hurdle on the way to human clinical studies,
and shows that we can dose a patient with BCT therapy
that can carry a drug cocktail or other anti-cancer drug
to the heart of tumors, maximizing their therapeutic effect.
(Figure 1)
In the summer of 2010 we performed our first attachment
of gold nanoparticles to our BCT therapy, demonstrating
that we could attach nanoparticle therapeutics
to our Salmonella that could serve as a target for specifically
destroying tumors with lasers and could eventually
be modified to carry drugs for release at the tumor
Figure 1 TRAMP prostate cancer mouse model.
Figure 2 Attachment of nanoparticles on outer
perimeter of cancer targeting (2631) cells.