Blueberries vs prostate cancer?

[Guest guest]

The below paper appears to promulgate the idea that blueberries would be useful

for

countering prostate cancer. However, my difficulty with such reports is that

they

fail to provide information on how much blueberries would be represented in the

extracts from the berries that are used in the experiments. Also, studying

cancer

cells in culture is highly different from studying cancer in people.

The pdf for the paper is unavailable.

IC50 to my understanding is the concentration of an agent required to cause 50%

inhibition in an activity. Thus a higher IC50 for an agent causes less

inhibition

of an activity.

Finding that the wild blueberries seemed to have less anti-prostate cancer

potential

was noted.

http://www.nature.com/pcan/journal/v9/n1/full/4500864a.html

Blueberries: The next therapy?

In early-stage prostate cancer, androgens increase proliferation; however, this

process can be delayed either by decreasing circulating androgens or by blocking

androgen receptors using antagonists. Yet advanced disease typically is

refractory

to androgen effects. Thus, researchers have sought plant-based therapies to

delay

the development and proliferation of advanced disease, and to date have

demonstrated

therapeutic potential in such substances as grape seed, soy, tomato, and green

tea.

Blueberries are a rich source of concentrated proanthocyanidins, which have

documented quinone reductase-inducing, ornithine decarboxylase-inhibiting, and

antiproliferative activity in various forms of cancer. Thus, Schmidt et al. from

the

University of Illinois at Urbana-Champaign investigated the effects of

proanthocyanidins from both wild and cultivated blueberry on the proliferation

of

LNCaP, an androgen-sensitive prostate cancer cells line, and DU145, an

androgen-insensitive prostate cancer cell line. Their results, published in

Cancer

Letters, are promising. A crude extract from both the wild and cultivated

blueberries was separated into five fractions. Fractions two through five of

each

type of blueberry were added to media containing each cell line, and the authors

found that two fractions from the cultivated blueberry and one fraction of the

wild

blueberry significantly reduced the growth of LNCaP cells. In DU145 cells,

however,

none of the fractions from wild blueberry significantly reduced proliferation,

and

only one fraction from cultivated blueberry showed mild antiproliferative

activity.

Indeed, in the LNCaP cell line, the antiproliferative activity in the cultivated

blueberry fruit fractions was significantly more potent than that found in the

wild

blueberries. The authors suggest several areas of future investigation with

regard

to the antiproliferative effects of blueberries on LNCaP cells, including

modulation

of PSA and androgen receptor gene expression, androgen agonist action, influence

on

the androgen receptor ligand biding specificity, and modulation of growth factor

production or growth factor expression.

Schmidt BM, Erdman JW Jr, Lila MA.

Differential effects of blueberry proanthocyanidins on androgen sensitive and

insensitive human prostate cancer cell lines.

Cancer Lett. 2006 Jan 18;231(2):240-6.

PMID: 16399225

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=pubmed & dopt=Abstra\

ct & list_uids=16399225 & query_hl=11 & itool=pubmed_docsum

-- Al Pater, alpater@...

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