Docosahexaenoic Acid (DHA) for Women With Breast Cancer in the Neoadjuvant Setting
Status:
Unknown status
Trial end date:
2021-09-01
Target enrollment:
Participant gender:
Summary
Docosahexaenoic acid (DHA) is an omega-3 long chain polyunsaturated fatty acid (n-3 LCPUFA).
N-3 LCPUFA are essential fatty acids in the diet. The majority of n-3 LCPUFA in the diet is
alpha-linolenic acid (ALA). While DHA can be synthesized from ALA and other n-3 LCPUFA in the
body, endogenous synthesis is low. Consequently, the only way to significantly increase
levels of DHA in tissues is by directly consuming this fatty acid. Common sources of DHA are
fatty fish, fish oil and omega-3 supplements and fortified foods.
DHA is readily incorporated into membrane phospholipids and induces changes in the properties
of the cell membrane including altered fluidity; permeability and membrane transport as well
as activity of membrane bound receptors and enzymes.
It is well established that changes in membrane DHA has multiple effects in the body,
including modulation of neurological, immune, and cardiovascular functions. In breast cancer,
DHA increases sensitivity of breast cancer cells to different chemotherapeutic agents, and in
animal models of breast cancer, dietary DHA decreases tumour growth. The investigator's
preclinical studies demonstrate that DHA increases efficacy of both doxorubicin and
docetaxel, two agents commonly used in the adjuvant setting for breast cancer treatment.
Furthermore, DHA mitigates chemotherapy induced weight loss in mice, and reduces paclitaxel
toxicities in breast cancer patients, strongly indicating that DHA protects against toxicity
in normal tissues. Directly relevant to this study, increased DHA in breast adipose tissue
correlates with improved response to chemotherapy, and increased dietary intake of n-3
LCPUFA, including DHA, results in increased DHA incorporation in breast adipose tissue.
Lastly, in advanced metastatic breast cancer, DHA supplementation correlated with improved
outcomes in a subset of patients. Consequently, the Investigators hypothesize that the
therapeutic index (efficacy: toxicity ratio) will be improved with the addition of DHA. In
this clinical trial, the Investigators will explore the benefit of DHA supplementation in
combination with neoadjuvant chemotherapy in patients with early breast cancer.
RESEARCH QUESTION & OBJECTIVES: The Investigators propose to evaluate incorporation of DHA in
women with breast cancer in treatment naïve patients in combination with chemotherapy, and
assess potential benefit of DHA supplementation in breast cancer patients, using change in
Ki67 labeling index (marker of proliferation) as a marker of efficacy. This study will
further investigate the relationship between DHA in plasma phospholipids (as a potential
biomarker of tumour incorporation) and effect on systemic immune function.
METHODS: Patients directed to receive chemotherapy will receive capsules, each containing a
minimum of 400 mg of DHA in the form of DHA enriched triglyceride oil or placebo (corn/soy
oil blend) to be taken orally (11 capsules/day, throughout day as preferred by participant)
for a total of 5 g DHA or placebo, for 12-18 weeks (84-126 days) beginning at the start of
the first cycle of chemotherapy, and continued throughout 4-6 cycles of chemotherapy (3
weeks/ cycle). DHA will be discontinued 21 days after the last administration of cytotoxic
chemotherapy. Tumour biopsies at baseline and post surgical removal will be assessed for Ki67
status as well as for markers of apoptosis and stem cell presence (by immunohistochemistry).
Blood samples taken at baseline prior to each round of chemotherapy will be assessed for
immune markers and plasma phospholipid content.
Phase:
Phase 2
Details
Lead Sponsor:
AHS Cancer Control Alberta
Collaborators:
Canadian Institutes of Health Research (CIHR) University of Alberta