Stress hormone may make prostate cancer cells resistant to treatment

Stress hormone may make prostate cancer cells resistant to treatment

Konduru S.R. Sastry, Yelena Karpova, Sergey Prokopovich, Adrienne J.
Smith, Brian Essau, Avynash Gersappe, Jonathan P. Carson, Michael J.
Weber, Thomas C. Register, Yong Q. Chen, Raymond B. Penn, and George
Kulik
Epinephrine protects cancer cells from apoptosis via activation of PKA
and BAD phosphorylation
J. Biol. Chem., Mar 2007; doi:10.1074/jbc.M611370200
< * w w w .jbc.org/cgi/content/abstract/M611370200v1>
< * w w w .jbc.org/cgi/reprint/M611370200v1> (full text PDF)

"The stress hormone epinephrine is known to elicit multiple
systemic effects that include changes in cardiovascular
parameters and immune responses. However, information about its
direct action on cancer cells is limited. Here we provide
evidence that epinephrine reduces sensitivity of cancer cells
to apoptosis through interaction with 2-adrenergic receptors.
The anti-apoptotic mechanism of epinephrine primarily involves
phosphorylation and inactivation of the pro-apoptotic protein
BAD by cAMP-dependent protein kinase. Moreover, BAD
phosphorylation was observed at epinephrine concentrations
found after acute and chronic psychosocial stress. Anti-
apoptotic signaling by epinephrine could be one of the
mechanisms by which stress promotes tumorigenesis and decreases
the efficacy of anti-cancer therapies."

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Stress hormone may make PCa cells resistant to treatment
< * w w w .urologytimes . com /urologytimes/article/articleDetail.jsp?id=420295&ref=25>

"The stress hormone epinephrine causes changes in prostate
cancer cells that may make them resistant to cell death,
scientists at Wake Forest University School of Medicine,
Winston-Salem, NC, report.

"These data imply that emotional stress may contribute to the
development of cancer and may also reduce the effectiveness of
cancer treatments," said George Kulik, DVM, PhD, senior
researcher on the project.

The goal of the current study, which is reported online in the
Journal of Biological Chemistry, was to determine whether there
is a direct link between stress hormones and changes in cancer
cells.

Studying prostate cancer cells in the laboratory, Dr. Kulik and
colleagues found that a protein called BAD, which causes cell
death, becomes inactive when cancer cells are exposed to
epinephrine. The connection between stress and prostate cancer
has been largely unexplored. However, recent studies suggest
that these laboratory findings may apply to cancer patients.

"A study from Canada showed that men who took beta-blockers for
hypertension for at least 4 years had an 18% lower risk of
prostate cancer," Dr. Kulik said. "These drugs block the
effects of epinephrine, which could explain the finding.
Another study of men after radical prostatectomy reported
increased mood disturbances, which are often associated with
elevated stress hormones.

"Although these studies do not directly address the role of
stress hormones, they suggest that stress hormones may play an
important role in prostate cancer.""




--
Matti Narkia