1. Princess Takamatsu Symp
1985;16:29-40
Multiethnic studies of diet, nutrition, and cancer in
Hawaii.
Kolonel LN, Hankin JH, Nomura AM
Epidemiologic studies of diet and cancer have been
facilitated in Hawaii by the
multiethnic composition of its population and the consequent
heterogeneity in
dietary intakes. Studies of migrant populations,
particularly the Japanese, have
firmly supported the conclusions that environmental factors
are of predominant
etiologic significance for most major sites of cancer, and
that these factors
may exert their influences at particular periods of life.
Recent observations on
Filipino migrants reproduce most of the findings in the
Japanese, although they
do not show the same abrupt increase in colon cancer rates
to the high levels
found in Caucasians. Data on dietary intakes in these
populations support
several of the prevailing hypotheses regarding the etiology
of certain
gastrointestinal and hormone-dependent cancers. Several
case-control studies of
diet and cancer have been completed or are ongoing in
Hawaii. Some of these have
included comparable studies in Japan, but the findings in
Hawaii have generally
not been reproduced in Japan. Weak associations with dietary
fat have been found
in Hawaii for breast cancer (particularly in Japanese women)
and for prostate
cancer (particularly in men greater than or equal to 70
years of age). Vitamin A
(especially carotene) has been shown to be inversely
associated with lung cancer
risk in men, but positively associated with prostate cancer
risk in older men.
Vitamin C may be inversely related to bladder cancer risk,
but has shown no
relationship to lung or prostate cancer risk. These and
other findings are
discussed in terms of future needs for epidemiologic
research in this field.
2. Br J Cancer
1997;75(1):149-55
Vitamins C and E, retinol, beta-carotene and dietary fibre
in relation to breast
cancer risk: a prospective cohort study.
Verhoeven DT, Assen N, Goldbohm RA, Dorant E, van 't Veer P,
Sturmans F, Hermus
RJ, van den Brandt PA
TNO Nutrition and Food Research Institute, Zeist, The
Netherlands.
Association between breast cancer risk and the intake of
vitamins C and E,
retinol, beta (beta)-carotene, dietary fibre, vegetables,
fruit and potatoes was
examined in The Netherlands Cohort Study, for 62,573 women
aged 55-69 years.
After 4.3 years of follow-up, 650 incident breast cancer
cases were identified.
After adjusting for traditional risk factors, breast cancer
risk was not
influenced by the intake of beta-carotene, vitamin E,
dietary fibre, supplements
with vitamin C, vegetables or potatoes. Fruit consumption
showed a
non-significant inverse association with breast cancer risk
(RR highest/lowest
quintile = 0.76, 95% CI 0.54-1.08). A small reduction in
risk was also observed
with increasing intake of dietary vitamin C (RR
highest/lowest quintile = 0.77,
95% CI 0.55-1.08). For retinol, a weak positive association
was observed (RR
highest/lowest quintile = 1.24, 95% CI 0.83-1.83). Among
subjects with a high
intake of polyunsaturated fatty acids (PUFAs), both
beta-carotene and vitamin C
intake showed a non-significant inverse association with
breast cancer risk
(P-trend = 0.15 and 0.16 respectively). Our findings do not
suggest a strong
role, if any, for intake of vitamins C and E, beta-carotene,
retinol, dietary
fibre, vegetables, fruit and potatoes in the aetiology of
breast cancer.
3. Cancer Lett 1996 Jun
5;103(2):183-9
Ascorbic acid (vitamin C) improves the antineoplastic
activity of doxorubicin,
cisplatin, and paclitaxel in human breast carcinoma cells in
vitro.
Kurbacher CM, Wagner U, Kolster B, Andreotti PE, Krebs D,
Bruckner HW
Department of Gynecology and Obstetrics, University of Bonn
Medical Center,
Germany.
Utilizing a microplate ATP bioluminescence assay, two
human breast carcinoma
cell lines, MCF-7 and MDA-MB-231, were tested against
doxorubicin (DOX),
cisplatin (DDP), and paclitaxel (Tx) alone and in
combination with ascorbic acid
(Vit C). In both cell lines, Vit C exhibited cytotoxic
activity at high
concentrations (i.e. 10(2)-10(3) microM). Both cell lines
also were resistant to
DOX. MCF-7 was found to be DDP-resistant, MDA-MB-231 was
moderately sensitive to
DDP. Both cell lines were strongly sensitive to Tx. Vit C
both at non-cytotoxic
(1 microM) and moderately cytotoxic concentrations (10(2)
microM) improved the
cytotoxicity of DOX, DDP, and Tx significantly. Combination
effects between Vit
C and DDP or Tx were partly synergistic and partly additive
or subadditive
whereas a consistent synergism was found between Vit C and
DOX. The mechanisms
by which Vit C potentiates the cytostatics studied are yet
unclear and should be
evaluated further.
4. Nutr Cancer
1996;25(2):173-7
Serum carotene, vitamin A, and vitamin C levels in breast
cancer and cancer of
the uterine cervix.
Ramaswamy G, Krishnamoorthy L
Department of Biochemistry, Kidwai Memorial Institute of
Oncology, Bangalore,
India.
Levels of carotene, vitamin A, and vitamin C measured in
the serum of patients
with cancer of the breast and uterine cervix were compared
with levels in
healthy controls and patients with benign diseases of the
breast and cervix.
Serum ascorbate levels were significantly lower in patients
with benign diseases
of the breast and cervix than in controls. In cancer
patients, there was a
significant trend of lower serum vitamin levels with
increasing stage of the
disease.
5. Jpn J Cancer Res 1994
Jun;85(6):572-7
Diet, serum markers and breast cancer mortality in
China.
Guo WD, Chow WH, Zheng W, Li JY, Blot WJ
Cancer Institute, Chinese Academy of Medical Sciences,
Beijing.
This county-based correlation study examined associations
of breast cancer
mortality with dietary habits and certain serum biochemical
markers, utilizing
data collected from an ecological survey in 65 Chinese rural
counties.
Univariate correlation and multivariate regression analysis
showed that
consumption of animal foods, including eggs, fish and meat,
was positively
linked to county-wide mortality rates of breast cancer in
Chinese women. No
clear associations between breast cancer mortality rates and
consumption of
green vegetables, carrots and fruits were observed in this
study. A modest
inverse correlation between serum vitamin C levels and
breast cancer mortality
was observed, while selenium levels were positively related
to the mortality
rates. Positive correlations for serum ferritin and
hemoglobin were found, in
agreement with recent reports of an elevated cancer risk
with increased body
iron stores. Limitations of these ecological data preclude
causal inferences,
but the findings provide clues to breast cancer risk and
protective factors in a
low incidence area of the world.
6. Nutr Cancer
1993;20(2):167-77
Dietary factors and survival from breast cancer.
Rohan TE, Hiller JE, McMichael AJ
National Cancer Institute of Canada (NCIC) Epidemiology
Unit, University of
Toronto, Ontario.
The association between self-reported intake of various
dietary factors at
diagnosis and survival from breast cancer was studied in a
population-based
cohort of breast cancer patients in Adelaide, South
Australia. These patients
had been recruited between 1982 and 1984 into a case-control
study of diet and
incident breast cancer. Of the 451 patients recruited
originally, 412 were
followed for a median interval of 5.5 years. There were
decreases in the risk of
death from breast cancer ranging from 25 to 40% at all
levels of energy and
protein intake above the baseline, whereas for fat intake
there was a 40%
increase in risk at the uppermost quintile level. There was
also some reduction
in risk at the upper levels of intake of beta-carotene and
vitamin C. However,
there were no dose-dependent variations in risk of death by
level of intake for
any of the dietary factors studied, and most of the
variation in risk that was
observed was relatively insubstantial.
7. Proc Natl Acad Sci U S A 1976
Oct;73(10):3685-9
Supplemental ascorbate in the supportive treatment of
cancer: Prolongation of
survival times in terminal human cancer.
Cameron E, Pauling L
Ascorbic acid metabolism is associated with a number of
mechanisms known to be
involved in host resistance to malignant disease. Cancer
patients are
significantly depleted of ascorbic acid, and in our opinion
this demonstrable
biochemical characteristic indicates a substantially
increased requirement and
utilization of this substance to potentiate these various
host resistance
factors. The results of a clinical trial are presented in
which 100 terminal
cancer patients were given supplemental ascorbate as part of
their routine
management. Their progress is compared to that of 1000
similar patients treated
identically, but who received no supplemental ascorbate. The
mean survival time
is more than 4.2 times as great for the ascorbate subjects
(more than 210 days)
as for the controls (50 days). Analysis of the survival-time
curves indicates
that deaths occur for about 90% of the ascorbate-treated
patients at one-third
the rate for the controls and that the other 10% have a much
greater survival
time, averaging more than 20 times that for the controls.
The results clearly
indicate that this simple and safe form of medication is of
definite value in
the treatment of patients with acvanced cancer.
8. Lepr India 1979
Oct;51(4):511-4
Effect of ascorbic acid on blood levels of DDS.
Venkatesan K, Bharadwaj VP, Girdhar BK
A study was undertaken to probe into the influence of
ascorbic acid on the
absorption and metabolism of administered DDS in leprosy
patients. Vit 'C'
supplementation did not generally exhibit any effect on
blood levels DDS except
in cases of BB and LL where only 8 hrs DDS values showed a
statistically
significant increase.
9. Compendium 1994 Jul;15(7):916,
918, 920 passim; quiz 930
Vitamin C (ascorbic acid): clinical implications for oral
health--a literature
review.
Fontana M
Oral Health Research Institute, Indianapolis, Indiana,
USA.
This article reviews the chemistry, functions, and
toxicity of vitamin C, as
well as its food sources, recommended daily allowance, and
laboratory
biochemical findings, to help clinicians understand and
recognize its systemic
and oral deficiency manifestations. An understanding of
these topics will help
the general dentist, periodontist, and oral surgeon
appropriately prescribe
vitamin C for their patients.
10. Int J Vitam Nutr Res
1982;52(3):333-41
The effect of ascorbic acid supplementation on periodontal
tissue ultrastructure
in subjects with progressive periodontitis.
Aurer-Kozelj J, Kralj-Klobucar N, Buzina R, Bacic M
In an attempt to determine the optimal daily ascorbic acid
requirement, the
effect of different levels of ascorbic acid intake on
collagen synthesis was
studied in a double-blind experimental design. By use of
electron microscopy,
interproximal gingival tissue sections in subjects consuming
between 20 to 35 mg
of ascorbic acid daily were examined before and after the
administration of
tablets containing 70 mg of ascorbic acid. The results
showed that practically
all subjects were affected by progressive periodontitis with
marked changes in
the connective tissue of the gingival lamina propria. After
six weeks of
supplementation with ascorbic acid, differences in the shape
and activity of
fibroblasts in the regenerative tissue of lamina propria
were observed. This has
resulted in the increased number of collagen bundles in
fibroblasts' periphery,
increased tonofibril content and an enlarged number of
desmosomes between
adjacent cells. It is concluded that the obtained results,
though suggesting
that the optimal daily ascorbic acid intake should be set
above the presently
recommended 30-50 mg, have to be quantified by a more
objective analytical
method.