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LE Magazine August 2002
Should Cancer
Patients Take Guarana?
Over the years there has been much debate over the use of
caffeine in general. Since guarana is an herb that contains a
form of caffeine called guaranine, one would have to postulate
the questions, Does guarana pose a health risk? Is it safe for
cancer patients to include it in their nutritional regimen? In
1987 the U.S. Food and Drug Administration found no evidence
that normal caffeine intake produced any increased risk to
health. The American Medical Association came to a similar
conclusion in relation to the health and safety of ingesting
caffeine. A published study in the Annals of Epidemiology (Michels,
et al 2002) found no relationship between coffee intake and
cancer risk, confirming the stance of the American Cancer
Society that there does not seem to be any relationship
between caffeine and occurrence of cancer.
Surprisingly, there are many published studies supporting
the use of caffeine in the treatment of cancer. The Journal of
Nutrition And Cancer (Lou, et al 1999) published a study in
which SKH-1 mice, who were at high risk of developing
malignant and nonmalignant tumors, received oral
ad`ministration of caffeine alone as their sole source of
drinking fluid for 18 to 23 weeks. The study revealed that not
only did the caffeine inhibit the formation and decrease the
size of nonmalignant tumors but malignant tumors as well.
In cancer cells, p53 gene mutations are the most common
alterations observed (50% to 60%) and a factor in carcinomas
and sarcomas. Caffeine has been shown to potentate the killing
of p53 defective cells by inhibiting the growth signal (G2)
and thus kill dividing cancer cells. Caffeine serves as a
model compound in establishing the principle agents that
override DNA-damage checkpoints that can be used to sensitize
cells to the killing effects of genotoxic drugs. This effect
has been demonstrated by several independdent research studies
and reported in the International Journal of Oncology (Jiang,
et al 2000); Radiotherapy And Oncology (Valenzuela, et al
2000); Current Biology (Blasina, et al 1999); International
Journal of Radiation Biology (Sakurai, et al 1999).
Further, caffeine has been shown to enhance the
cytotoxicity of chemotherapy drugs, cisplatin and
camptothecin, in human brain tumor cell lines according to
Experimental Cell Research (Janss, et al 1998). Anticancer
Research (Tsuchiya, et al 2000) reported that
caffeine-assisted chemotherapy has been shown to minimize
tumor excision for nonmetastatic osteosarcoma by enhancing
tumor necrosis. Interestingly, caffeine potentiated
radiochemotherapy sensitizing cells to the killing effects of
genotoxic drugs with a mutant-type p53 gene. This was not the
case after irradiation in combination with caffeine in cells
with a mutant-type p53 through a p53-independent pathway,
acording to a study published in the Cancer Letters (Higuchi
et al 2000). Further, Radiation Research: A Twentieth Centure
Perspective (Qi et al 2002) reports that caffeine not only
induced p53-independent arrest and enhanced radiation-induced
apoptosis (cell death), but caffeine in a dose dependent
manner induced apoptosis independent of any other factors.
Numerous studies have demonstrated caffeine's potential to
provide cancer-preventive protection by inhibiting the
formation and decreasing the size of both malignant and
nonmalignant tumors. Further, caffeine has also been shown in
studies to enhance the cytotoxicity of chemotherapy and
radiochemotherapy drugs by sensitizing cells to the killing
effects of these genotoxic durgs. However, the most compelling
finding was caffeine's ability to induce apoptosis independent
of any other factor. While the debate over the use of caffeine
continues, clearly, these findings are significant and would
suggest a closer examination of the fole of caffeine in the
prevention and treatment of cancer.
CLA is a popular dietary supplement used by cancer
patients. Based on evidence indicating caffeine's potential
anticancer benefit, cancer patients may consider using a new
CLA supplement that is fortified with guarana.
Find out more about Super
CLA with Guarana
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Caution: While
caffeine may prove beneficial as a potential adjuvant
cancer therapy, some sensitive individuals might not be
able to tolerate caffeine's stimulating effects on the
central nervous system. Caffeine may produce a variety of
symptoms including restlessness, nausea, headache, tense
muscles, sleep disturbances and tachycardia. Therefore,
caution should be used when including caffeine in any
nutritional program.
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References
Blasina A , Price BD , Turenne GA ,
McGowan CH. Caffeine inhibits the checkpoint kinase ATM. Radiotherapy And Oncology 1999
9(19): 1135-8.
Higuchi K , Mitsuhashi N , Saitoh J , Maebayashi K , Sakurai
H , Akimoto T , Niibe H. Caffeine enhanced radiosensitivity of
rat tumor cells with a mutant-type p53 by inducing apoptosis
in a p53-independent manner. Cancer Letters 2000
152(2):157-62.
Janss AJ , Levow C , Bernhard EJ , Muschel RJ , McKenna WG,
Sutton L, Phillips PC. Caffeine-potentiated chemotherapy and
conservative surgery for high-grade soft-tissue sarcoma. Experimental Cell Research 1998
243(1): 29-38.
Jiang X, Lim LY, Daly JW, Li AH. Structure-activity
relationships for G2 checkpoints inhibition by caffeine
analogs. International Journal of
Oncology 2000 16(5): 971-8.
Lou YR, LU YP, Xie JG, Huang MT, Conney AH. Effects of oral
administration of tea, decaffeinated tea, and caffeine on the
formation and growth of tumors in high risk SKH-1 mice
previously treated with ultraviolet B light. The Journal of Nutrition And
Cancer 1999 33(2): 146-53.
Michels KB, Holmberg L, BergkvistL, Wolk A. Coffee, tea, and
caffeine consumption and breast cancer incidence in a cohort
of Swedish woman. Annals of
Epidemiology 2002 12(1): 21-6.
Qi W, Qiao D, Martinez JD. Caffeine induces TP53-independent
G(1)-phase arrest and apoptosis in human lung tumor cells in a
dose-dependent manner. Radiation
Research: A Twentieth Century Perspective 2002 157(2):
166-74.
Sakurai H, Mitsuhashi N , Tamaki Y, Akimoto T, Murata O,
Kitamoto Y, Maebayashi K, Ishikawa H, Hayakawa K, Niibe H.
Interaction between low dose-rate irradiation, mild
hyperthermia and low-dose caffeine in a human lung cancer cell
line. International Journal Of
Radiation Biology 1999 75(6): 739-45.
Tsuchiya H, Tomita K, Mori Y, Asada N, Morinaga T, Kitano S,
Yamamoto N. Caffeine-assisted chemotherapy and minimized tumor
excision for nonmetastatic osteosarcoma. Anticancer Research 2000 18(1B):
657-66.
Valenzuela MT, Mateos S, Ruiz de Almodóvar JM,
McMillan TJ. Variation in sensitizing effect of caffeine in
human tumour cell lines after gamma-irradiation. Radiotherapy And Oncology 2000
54(3): 261-71.
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