e prostate cancer specimens, in 0 percent
of the no-cancer group and in 6.5 percent in a general population
sample of 898 Europeans.
To determine whether mtDNA mutations are causally related to prostate
cancer, the researchers introduced into a prostate cancer cell line
mtDNAs harboring a known disease-causing mtDNA mutation and, as a
control, the same mtDNA but without the disease mutation. They then
injected these modified prostate cancer cells into mice to assess their
tumor-forming ability. The prostate cancer cells with the mutant mtDNAs
generated tumors that were on average seven times larger than the
prostate cancer cells with normal mitochondria. Hence, the deleterious
mtDNA mutation greatly enhanced prostate cancer growth.
Since mitochondria make oxygen radicals as a by-product of making
energy, and oxygen radicals can stimulate cell growth, the researchers
then tested the tumors for oxygen radical production. The tumors with
the mutant mtDNAs generated significantly more oxygen radicals than
those with normal ntDNAs, suggesting that this may be an important
contributory factor in the mitochondrial enhancement of prostate cancer
tumor growth. Because the study found that COI mutations were common in
the general population (7.8 percent), but very infrequent (<2
percent) in men without prostate cancer, the investigators noted that
men harboring these mutations are at increased risk for developing
prostate cancer.
"We believe this study provides convincing evidence that mitochondrial
mutations play an important role in prostate cancer," said Dr. Petros.
"This is the first evidence that individuals who inherit a mutation of
the mitochondrial DNA are at an increased risk of developing prostate
cancer later in life. Interestingly, mitochondrial DNA is inherited
from your mother, so this may explain those familial cases that are not
passed from father to son, but rather through the unaffected mother to
her sons."
'"/>Source:
Eurekalert
Page: 1 2 Related biology news :1.
Mitochondrial DNA sequencing tool updated2.
Mitochondrial genes move to the nucleus -- but its not for the sex3.
Novel technology detects human DNA mutations4.
Bioelectronic ‘signatures?hold key to DNA mutations5.
Multi-species genome comparison sheds new light on evolutionary processes, cancer mutations6.
DNA size a crucial factor in genetic mutations, study finds7.
New view of cancer: Epigenetic changes come before mutations8.
ASU researchers wire DNA to identify mutations9.
Carbon nanotubes that detect disease-causing mutations developed by Pitt researcher10.
Minor mutations in avian flu virus increase chances of human infection11.
New findings offer more complete view of breast cancer gene mutations in US population