American Association for Cancer Research, April 17-21, 2010Last Updated: April 26, 2010.
The American Association for Cancer Research's 101st Annual Meeting took place April 17 to 21 in Washington, D.C., and attracted nearly 18,000 participants from around the world. The conference focused on advances in cancer research, including innovative preclinical science, clinical trial results, and novel approaches and technologies being used in research.
Key highlights included results from the Biomarker-integrated Approaches of Targeted Therapy for Lung Cancer Elimination (BATTLE) trial and an update of the Study of Tamoxifen and Raloxifene (STAR) P-2 trial. Other presentations focused on discoveries in microRNAs (miRNAs) and advances in cancer genetics, nanotechnology, and systems biology.
In the phase II BATTLE trial, presented by Edward S. Kim, M.D., of the University of Texas M.D. Anderson Cancer Center in Houston, researchers found that non-small cell lung cancer (NSCLC) treatment with currently available drugs based on a patient's tumor biomarkers provides better outcomes than treatment with existing drugs not based on their biomarkers.
The BATTLE trial tested 11 biomarkers from four NSCLC molecular pathways. Two-hundred fifty-five participants were randomized based on inclusion criteria and biomarker analysis to erlotinib, sorafenib, vandetanib or erlotinib plus bexarotene. The researchers found that the overall disease control rate at two months was 46 percent, and median overall survival was nine months. In addition, progression-free survival was 1.9 months, and one-year survival was 39 percent. One of the key findings was that sorafenib was effective for 61 percent of participants who had mutations in the KRAS gene. Participants with wild type or all other KRAS substitutions demonstrated better outcomes than those with mutant KRAS Cys amino acid substitution.
Kim had previously presented data in 2008 that demonstrated no difference with gefitinib versus docetaxel in NSCLC cancer patients with KRAS mutations, raising questions about the effectiveness of KRAS testing in NSCLC. "However, in this study, sorafenib performed well, controlling disease," Kim said.
One author disclosed financial ties to AstraZeneca and Oncothyreon Inc.
An update of the STAR P-2 trial presented by Lawrence Wickerham, M.D., of Allegheny General Hospital in Pittsburgh, during a late breaking session, showed that both raloxifene and tamoxifen remain effective options to prevent breast cancer over the longer term. The study evaluated 19,490 postmenopausal women at a higher risk for developing breast cancer being treated with tamoxifen or raloxifene with median follow-up of 81 months.
The researchers found that, over 81 months, raloxifene retained 76 percent of the effectiveness of tamoxifen in preventing invasive disease. In addition, raloxifene made gains (becoming closer to tamoxifen) in effectively treating noninvasive disease, with lower endometrial cancer incidence and much less toxicity overall.
"Tamoxifen has not been overwhelmingly embraced due to associated toxicities, and now we have another option," Wickerham said.
To coincide with this presentation, the full study was published online April 19 in Cancer Prevention Research. Two authors disclosed relationships with Astra-Zeneca and Eli Lilly.
With advances in genetic sequencing and expression analysis, discoveries in miRNAs are providing further insight into understanding possible targets and resistance mechanisms, leading to potentially more effective cancer treatments. In one study presented at the conference, Liselle Bovell, a graduate student at the University of Alabama in Birmingham, and colleagues evaluated a panel of five miRNAs: miR-20a, miR-21, miR-106a, miR-181b and miR-203 in 104 black subjects and 114 white subjects.
The researchers found that all five miRNAs were overexpressed in colorectal cancers, compared to control tissue. In addition, increased expression of miR-106a was associated with poorer survival among blacks and whites; and, increased expression of miR-181b and miR-203 were each significantly associated with poorer survival in blacks but not in whites.
"I think the long-term implications of our research [is] moving in the direction of individualized medicine. Studies have been conducted in research laboratories to assess the levels of circulating miRNAs in the blood, and hopefully this could be used in the future as a minimally invasive screening method in the clinic," Bovell said.
In another study, Sumaiyah K. Rehman, a graduate research assistant at the University of Texas M.D. Anderson Cancer Center in Houston, and colleagues showed that overexpression of miR-21 and reduced phosphatase and tensin homolog (PTEN) expression in breast cancer cells increases resistance to trastuzumab (Herceptin).
"If we know in advance who is going to respond to treatment, then this could possibly save patients from undergoing this treatment unnecessarily," Rehman said in a statement.
In an animal study presented by Eva Hernando, Ph.D., of the New York University School of Medicine in New York City, researchers evaluated the role of specific miRNAs in vitro and in vivo in the signaling of melanoma brain metastasis in mice. The study found that some miRNAs increased the ability of melanoma cells to metastasize and adhere to brain cells, with other miRNAs assisting in the transport of cells across the blood-brain barrier.
"Over the past few years, more and more reports have shown significant and important roles for miRNAs in normal physiological processes and in several pathologies, including cancer," Hernando said in a statement.
AACR: Breast Density Strong Predictor of Breast Cancer Risk
WEDNESDAY, April 21 (HealthDay News) -- Breast density appears to be a strong biomarker of breast cancer risk, according to research presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C., with breast density research the focus of the following three studies.
AACR: EGFR Levels Up Prior to Breast Cancer Diagnosis
WEDNESDAY, April 21 (HealthDay News) -- Epidermal growth factor receptor (EGFR) levels may be elevated in women within 17 months prior to breast cancer diagnosis, and an increase in body mass index (BMI) in midlife may lead to a substantially increased risk of postmenopausal breast cancer, according to the results of two studies presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C.
AACR: Secondhand Smoke Associated With Bladder Cancer
TUESDAY, April 20 (HealthDay News) -- Secondhand smoke, high consumption of red or fried meat, and certain genetic variants are associated with an increased risk of bladder cancer, according to the results of two studies presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C.
AACR: Weight Gain Tied to Prostate Cancer Recurrence
TUESDAY, April 20 (HealthDay News) -- Obesity and weight gain are associated with an increased risk of prostate cancer recurrence after prostatectomy, and obesity and smoking are associated with an increased risk of dying from the cancer once a patient is diagnosed, according to two studies presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C.
AACR: Metformin May Inhibit Lung Tumor Growth
TUESDAY, April 20 (HealthDay News) -- Metformin, a standard type 2 diabetes treatment, may help prevent lung cancer in smokers by inhibiting tumor growth, according to an animal study presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C.
AACR: Statins Do Not Protect Against Colorectal Adenomas
MONDAY, April 19 (HealthDay News) -- Statins do not appear to prevent colorectal cancer in high-risk individuals, and may actually increase the risk of developing colorectal adenomas, according to the results of a secondary analysis of the Adenoma Prevention with Celecoxib (APC) trial presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C. To coincide with this presentation, the full study was published online April 19 in Cancer Prevention Research.
AACR: Researchers Identify Prostate Cancer Biomarkers
MONDAY, April 19 (HealthDay News) -- A novel application of the Prostate Health Index (PHI) and DNA content measures may effectively predict prostate cancer progression, though pro-prostate-specific antigen (PSA) levels alone may not, according to a study presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C.
AACR: Vitamins and Calcium May Lessen Breast Cancer Risk
MONDAY, April 19 (HealthDay News) -- Vitamins and calcium supplements are both associated with higher DNA repair capacity and may reduce the risk of breast cancer, according to a study presented at the annual meeting of the American Association for Cancer Research, held from April 17 to 21 in Washington, D.C.