Can A Diet Low In Carbs & High On Protein Help In the Fight Against Cancer?

Eating a low-carbohydrate, high-protein diet may reduce the risk of cancer and slow the growth of tumors already present, according to a study published in Cancer Research, a journal of the American Association for Cancer Research.

Gerald Krystal, Ph.D., Professor, Pathology & Laboratory Medicine, University of British Columbia; Distinguished Scientist, Terry Fox Laboratory, British Columbia Cancer Agency

Eating a low-carbohydrate, high-protein diet may reduce the risk of cancer and slow the growth of tumors already present, according to a study published in Cancer Research, a journal of the American Association for Cancer Research.

The study was conducted in mice, but the scientists involved agree that the strong biological findings are definitive enough that an effect in humans can be considered.

“This shows that something as simple as a change in diet can have an impact on cancer risk,” said lead researcher Gerald Krystal, Ph.D., a distinguished scientist at the British Columbia Cancer Research Centre.

Cancer Research editor-in-chief George Prendergast, Ph.D., CEO of the Lankenau Institute for Medical Research, agreed. “Many cancer patients are interested in making changes in areas that they can control, and this study definitely lends credence to the idea that a change in diet can be beneficial,” said Prendergast, who was not involved with the study.

Krystal and his colleagues implanted various strains of mice with human tumor cells or with mouse tumor cells and assigned them to one of two diets. The first diet, a typical Western diet, contained about 55 percent carbohydrate, 23 percent protein and 22 percent fat. The second, which is somewhat like a South Beach diet but higher in protein, contained 15 percent carbohydrate, 58 percent protein and 26 percent fat. They found that the tumor cells grew consistently slower on the second diet.

As well, mice genetically predisposed to breast cancer were put on these two diets and almost half of them on the Western diet developed breast cancer within their first year of life while none on the low-carbohydrate, high-protein diet did. Interestingly, only one on the Western diet reached a normal life span (approximately 2 years), with 70 percent of them dying from cancer while only 30 percent of those on the low-carbohydrate diet developed cancer and more than half these mice reached or exceeded their normal life span.

Krystal and colleagues also tested the effect of mTOR inhibitor CCI-779 (temsirolimus/Torisel®), which inhibits cell growth, and COX-2 inhibitor celecoxib (Celebrex®), which reduces inflammation, on tumor development, and found these agents had an additive effect in the mice fed the low-carbohydrate, high-protein diet.

When asked to speculate on the biological mechanism, Krystal said that tumor cells, unlike normal cells, need significantly more glucose to grow and thrive. Restricting carbohydrate intake can significantly limit blood glucose and insulin, a hormone that has been shown in many independent studies to promote tumor growth in both humans and mice.

Furthermore, a low-carbohydrate, high-protein diet has the potential to both boost the ability of the immune system to kill cancer cells and prevent obesity, which leads to chronic inflammation and cancer.

About the American Association For Cancer Research (AACR)

The mission of the AACR is to prevent and cure cancer. Founded in 1907, the AACR is the world’s oldest and largest professional organization dedicated to advancing cancer research. The membership includes 33,000 basic, translational and clinical researchers; health care professionals; and cancer survivors and advocates in the United States and more than 90 other countries. The AACR marshals the full spectrum of expertise from the cancer community to accelerate progress in the prevention, diagnosis and treatment of cancer through high-quality scientific and educational programs. It funds innovative, meritorious research grants, research fellowships and career development awards. The AACR Annual Meeting attracts more than 18,000 participants who share the latest discoveries and developments in the field. Special conferences throughout the year present novel data across a wide variety of topics in cancer research, treatment and patient care. Including Cancer Discovery, the AACR publishes seven major peer-reviewed journals: Cancer Research; Clinical Cancer Research; Molecular Cancer Therapeutics; Molecular Cancer Research; Cancer Epidemiology, Biomarkers & Prevention; and Cancer Prevention Research. AACR journals represented 20 percent of the market share of total citations in 2009. The AACR also publishes CR, a magazine for cancer survivors and their families, patient advocates, physicians and scientists.

Sources:

• Ho VW, Leung K, Hsu A, et. al. A Low Carbohydrate, High Protein Diet Slows Tumor Growth and Prevents Cancer Initiation. Cancer Res June 14, 2011 ; Published Online First June 14, 2011; doi:10.1158/0008-5472.

• Low-Carbohydrate, High-Protein Diets May Reduce Both Tumor Growth Rates and Cancer Risk, Press Release, American Association For Cancer Research, June 14, 2011.

2011 AACR Annual Meeting: Select Ovarian Cancer Presentations & Abstracts Available Online

The 102nd American Association For Cancer Research (AACR) Annual Meeting will be held from Saturday, April 2 through Wednesday, April 6, 2011, at the Orange County Convention Center located in Orlando, Florida.  Select ovarian cancer presentations and abstracts are available online.

The 102nd American Association For Cancer Research (AACR) Annual Meeting will be held from Saturday, April 2 through Wednesday, April 6, 2011, at the Orange County Convention Center located in Orlando, Florida.  Select ovarian cancer meeting presentations and abstracts are now available online.

Once again, the AACR will host and organize an exciting program on the best and latest in cancer research, in which a large cross section of the cancer research community will participate, to advance the cause of treating and preventing cancer. The meeting program not only reflects the AACR’s strengths in basic, translational, and clinical research, but also emphasizes the productive interfaces emerging between these once-separated disciplines. The program also captures the advances on all of these fronts, with a range of speakers and participants who are leaders in research: cancer mechanisms, systems approaches to cancer biology, diagnostics and therapeutics, translation of advances to the clinic, and cutting-edge science in the prevention and early interception of cancer.

In advance of the actual meeting, you can review select ovarian cancer meeting and poster presentations that relate to basic, clinical, epidemiological, and translational research.

To view all available ovarian cancer meeting and poster presentations, CLICK HERE, and then click the “advanced search button,” and under “Abstract Organ Site,” choose “gynecological cancer:  ovarian cancer,” then click “search” at the top or bottom of the page .

To view a list of all available AACR program ovarian cancer-related webcasts available during and/or after the meeting, CLICK HERE and (i) type in “ovarian cancer” in the search box; (ii) choose “sessions (with details)” under the “Browse By” menu at the top of the page; and (iii) choose only “2011” within the  search filter (i.e., uncheck conference years 2004 – 2010), then click “Update Filter.” (note: you can also search for free and/or paid webcasts by using the search filter on this page).

Libby’s H*O*P*E*™ will post newsworthy ovarian cancer information that is disclosed during the course of the AACR Annual Meeting.

About the American Association For Cancer Research

The mission of the American Association for Cancer Research is to prevent and cure cancer. AACR was founded in 1907 by a group of 11 physicians and scientists interested in research “to further the investigation and spread the knowledge of cancer.” The AACR is the world’s oldest and largest professional organization dedicated to advancing cancer research. The membership includes 33,000 basic, translational and clinical researchers; health care professionals; and cancer survivors and advocates in the United States and more than 90 other countries.

The AACR marshals the full spectrum of expertise from the cancer community to accelerate progress in the prevention, diagnosis and treatment of cancer through high-quality scientific and educational programs. It funds innovative, meritorious research grants, research fellowships and career development awards. The AACR Annual Meeting attracts more than 18,000 participants who share the latest discoveries and developments in the field. Special conferences throughout the year present novel data across a wide variety of topics in cancer research, treatment and patient care. Including Cancer Discovery, the AACR publishes seven major peer-reviewed journals: Cancer Research; Clinical Cancer Research; Molecular Cancer Therapeutics; Molecular Cancer Research; Cancer Epidemiology, Biomarkers & Prevention; and Cancer Prevention Research. AACR journals represented 20 percent of the market share of total citations in 2009. The AACR also publishes CR, a magazine for cancer survivors and their families, patient advocates, physicians and scientists.

Outside-the-Box: The Rogosin Institute Is Fighting Cancer With Cancer Cells In Clinical Trials

Researchers at the Rogosin Institute are using cancer “macrobeads” to fight cancer.  Cancer cells in the beads secrete proteins which researchers believe could signal a patient’s cancer to stop growing, shrink or even die. The treatment is currently being tested in human clinical trials.

Two groundbreaking preclinical studies demonstrate for the first time that encapsulated mouse kidney cancer cells inhibit the growth of freely-growing cancer cells of the same or different type in a laboratory dish and in tumor-bearing animals. These findings support the hypothesis that cancer cells entrapped in seaweed-based gel, called “macrobeads,” send biological feedback or signals to freely-growing tumors outside the macrobead to slow or stop their growth. Both studies (cited below) are published in the on-line January 24, 2011 issue of Cancer Research, a publication of the American Association For Cancer Research.

Barry H. Smith, M.D., Ph.D., Director, The Rogosin Institute; Professor, Clinical Surgery, Weill Cornell Medical College

The Rogosin Institute, an independent not-for-profit treatment and research center associated with New York-Presbyterian Hospital and Weill Cornell Medical College, developed the cell encapsulation technology that facilitated production of the macrobead and applied this technology in conducting preclinical studies. The research team was headed by Barry H. Smith, M.D., Ph.D.,  the Director of The Rogosin Institute, Professor of Clinical Surgery at the Weill Cornell Medical College, and lead author of the studies. Findings in the studies to date are consistent with the hypothesis that when macrobeads are implanted in a host, the encapsulated cells are isolated from the host’s immune system but continue to maintain their functionality.

In addition to the standard preclinical in vivo and in vitro experiments, a clinical veterinary study was conducted in cats and dogs suffering from various spontaneous (non-induced) cancers. More than 40 animals were treated with the macrobead technology. Consistent results, measured both in terms of tumor response and animal well-being, occurred with prostate, liver and breast cancer, as well as lymphoma. Additional research revealed that regardless of the animal specie or type of cancer cell that was encapsulated, the macrobead technology inhibited cancer growth across all species and cancer types tested.  The results have included slowed tumor growth or, in some cases, necrosis and elimination of tumors and the restoration of a normal animal lifespan.

Cancer macrobead therapy has proceeded to human clinical testing. A Phase 1 trial in more than 30 patients evaluated the safety of macrobeads implanted in the abdominal cavity as a biological treatment of end-stage, treatment-resistant, epithelial-derived cancer. Based on the safety profile data, Phase 2 efficacy trials are in progress in patients with colorectal cancer, pancreatic cancer and prostate cancer. The Phase 1 trial remains open to a range of epithelial-derived cancers, including ovarian.  To date, the Rogosin Institute research team has not found evidence to indicate that placing mouse tumors in humans or other animal species causes harm or side-effects.

Scientists are testing whether macrobeads containing cancer cells can be implanted into patients and communicate with the patient’s tumor to stop growing, shrink or die.

Step 1:  Small beads are made from a seaweed-derived sugar called agarose and mixed with 150,000 mouse kidney cancer cells, and a second layer of agarose is added, encapsulating the cancer cells.

Step 2:  Within 3-to-10 days, 99% of the kidney cancer cells die.  The remaining cells have traits similar to cancer stem cells.

Step 3:  The stem cells begin to recolonize the bead.  The colonies increase in sufficient numbers within a few weeks to reach a stable state.

Step 4:  The beads begin to release proteins —  chemical signals reflecting that the beads have sufficient numbers of cells for growth regulators to kick in.

Step 5: Several hundred beads (depending on patient’s weight) are implanted in the abdominal cavity in a laparoscopic surgical procedure.  The cancer cells are trapped in the beads; preventing their circulation elsewhere in the body and protecting them from attack by the body’s immune system.

Step 6: In animal studies, researchers believe some proteins released from the beads reached tumors elsewhere in the body and tricked them into sensing that other tumor cells are nearby.

Step 7:  As a result, researchers believe tumors in some animals stopped growing, shrank or died.  The hypothesis is being tested in people with cancer.

Howard Parnes, M.D., Chief, Prostate & Urologic Cancer Research Group, Division of Cancer Prevention, National Cancer Institute

“This is a completely novel way of thinking about cancer biology,” says Howard L. Parnes, a researcher in the Division of  Cancer Prevention at the National Cancer Institute who is familiar with the work but was not involved with it. “We talk about thinking outside the box. It’s hard to think of a better example.” “They demonstrate a remarkable proof of principle that tumor cells from one animal can be manipulated to produce factors that can inhibit the growth of cancers in other animals,” Dr. Parnes says. “This suggests that these cancer inhibitory factors have been conserved over millions of years of evolution.”

“Macrobead therapy holds promise as a new option in cancer treatment because it makes use of normal biological mechanisms and avoids the toxicities associated with traditional chemotherapy,” said Dr. Barry Smith. “The results of our research show that this approach is not specific to tumor type or species so that, for example, mouse cells can be used to treat several different human tumors and human cells can be used to treat several different animal tumors.”

“Because cancer and other diseases are their own biological systems, we believe that the future of effective disease treatment must likewise be biological and system-based,” said Stuart Subotnick, CEO of Metromedia Bio-Science LLC. “Many of the existing therapies are narrow, targeted approaches that fail to treat diseases comprehensively. In contrast, our unique macrobead technology delivers an integrated cell system that alters disease processes and utilizes the body’s natural defense mechanisms. The goal is to repair the body and not merely treat the symptoms.”

It is well-known that proof of anti-tumor activity in treating animals does not represent guaranteed effectiveness in humans. But, assuming the macrobead therapy proves ultimately effective in humans, it would represent a novel approach to treating cancer and challenge existing scientific dogmas.

The cancer macrobead therapy described above is backed by Metromedia Company, a privately held telecommunications company which was run by billionaire John Kluge until his recent death. The Metromedia Biosciences unit has invested $50 million into the research.  If the treatment proves successful in humans, a large part of the revenue generated will be contributed to Mr. Kluge’s charitable foundation.

About Metromedia Bio-Science LLC

Metromedia Bio-Science LLC, in conjunction with The Rogosin Institute, utilizes the novel cell encapsulation technology to conduct research into the treatment of various diseases, including cancer and diabetes, and the evaluation of disease therapies. Metromedia Bio-Science LLC is an affiliate of Metromedia Company, a diversified partnership founded by the late John W. Kluge and Stuart Subotnick.

About The Rogosin Institute

The Rogosin Institute is an independent not-for-profit treatment and research center associated with New York-Presbyterian Hospital (NYPH) and Weill Cornell Medical College. It is one of the nation’s leading research and treatment centers for kidney disease, providing services from early stage disease to those requiring dialysis and transplantation. It also has programs in diabetes, hypertension and lipid disorders. The Institute’s cancer research program, featuring the macrobeads, began in 1995. The Rogosin Institute is unique in its combination of the best in clinical care with research into new and better ways to prevent and treat disease.

References:

• Smith BH, Gazda LS, Conn BL, et. al.  Integrated Systems and Technologies: Three-Dimensional Culture of Mouse Renal Carcinoma Cells in Agarose Macrobeads Selects for a Subpopulation of Cells with Cancer Stem Cell or Cancer Progenitor Properties.  Cancer Res; 71(3); 716–24, published online first January 24, 2011; doi:10.1158/0008-5472. CAN-10-2254.

• Smith BH, Gazda LS, Conn BL, et. al. Integrated Systems and Technologies:  Hydrophilic Agarose Macrobead Cultures Select for Outgrowth of Carcinoma Cell Populations That Can Restrict Tumor Growth.  Cancer Res; 71(3); 725–35, published online first January 24, 2011; doi:10.1158/0008-5472. CAN-10-2258.

• Preclinical Studies Show Encapsulated Cancer Cells Slow or Stop Growth of Freely-Growing Tumors In Animals, Press Release, Metromedia Bio-Science LLC, January 25, 2011.

• Novel Effort To Fight Cancer With Cancer Cells, by John Winslow, Business Section, Wall Street Journal Online, January 25, 2011.

Clinical Trials:

• Use of Mouse Renal Adenocarcinoma Cell-containing Agarose-agarose Macrobeads in the Treatment of Patients With End-stage, Treatment-resistant Epithelial-derived Cancer [Phase I Study], Clinical Trial Summary (NCT00283075), ClinicalTrials.gov.

• An Open-Label Phase 2 Efficacy Trial of the Implantation of Mouse Renal Adenocarcinoma Cell-Containing Agarose-Agarose Macrobeads in the Treatment of Patients With Treatment-Resistant, Metastatic Pancreatic or Colorectal Adenocarcinoma, Clinical Trial Summary (NCT01053013), ClinicalTrials.gov.

• An Open-Label, Phase 2 Efficacy Trial of the Implantation of Mouse Renal Adenocarcinoma Cell-Containing Agarose- Agarose Macrobeads in the Treatment of Patients With Castration-Resistant Prostate Cancer Resistant to Docetaxel, Clinical Trial Summary (NCT01174368), ClinicalTrials.gov.

Estrogen Replacement Therapy Speeds Growth of ER+ Ovarian Cancer & Increases Risk of Lymph Node Metastasis

Estrogen therapy used by menopausal women causes “estrogen receptor positive” (ER+) ovarian cancer to grow five times faster, according to a new study being published by researchers at the University of Colorado Cancer Center in the November 1 issue of Cancer Research.

Estrogen therapy used by menopausal women causes so-called “estrogen receptor positive” (ER+) ovarian cancer to grow five times faster, according to a new study being published tomorrow by researchers at the University of Colorado Cancer Center.

Menopausal estrogen replacement therapy (ERT) also significantly increases the likelihood of the cancer metastasizing to the lymph nodes, according to the study, which will be published in the November 1 issue of Cancer Research. The study was released online on Oct. 19, 2010. Cancer Research, published by the American Association for Cancer Research, is the world’s largest (based upon circulation) medical journal devoted specifically to cancer research.

The effect of ERT was shown in mouse models of estrogen receptor positive (ER+) ovarian cancer, which accounts for about 60 percent of all human ovarian cancer cases. Ovarian cancer is one of the deadliest cancers affecting women. This year alone, nearly 22,000 women will be newly diagnosed with ovarian cancer and an estimated 13,850 women will die from the disease, according to the National Cancer Institute.

Monique Spillman, M.D., Ph.D., Gynecologic Oncologist, University of Colorado Hospital; Assistant Professor, Obstetrics & Gynecology, University of Colorado School of Medicine.

“We showed that estrogen replacement substantially increases proliferation and risk of distant lymph node metastasis in ER+ tumors,” says Monique Spillman, M.D., Ph.D., the study’s lead researcher, a gynecologic oncologist at University of Colorado Hospital and assistant professor at of obstetrics and gynecology at the University of Colorado School of Medicine.

For the first time, Spillman and her team measured ovarian cancer growth in the abdomen of mice using novel techniques for visualizing the cancer. In mice with ER+ ovarian cancer cells, which were tagged with a firefly-like fluorescent protein that allowed them to be tracked, the introduction of estrogen therapy made the tumors grow five times faster than in mice that did not receive the ERT. The risk of the cancer moving to the lymph nodes increased to 26 percent in these mice compared with 6 percent in mice that did not receive ERT.

The team also found that the estrogen-regulated genes in ovarian cancer reacted differently than ER+ genes found in breast cancer, helping to explain why current anti-estrogen therapies used with breast cancer, such as tamoxifen, are largely ineffective against ovarian cancer.

“Breast cancer and ovarian cancer are often linked when talking about hormone replacement therapy, but we found that only 10 percent of the ER+ genes overlapped,” Spillman says. “We were able to identify estrogen-regulated genes specific to ER+ ovarian cancer that are not shared with ER+ breast cancers. We believe these genes can be specifically targeted with new anti-estrogen therapies that could more effectively treat ER+ ovarian cancers.”

“Breast cancer and ovarian cancer are often linked when talking about hormone replacement therapy, but we found that only 10 percent of the ER+ genes overlapped.  We were able to identify estrogen-regulated genes specific to ER+ ovarian cancer that are not shared with ER+ breast cancers. We believe these genes can be specifically targeted with new anti-estrogen therapies that could more effectively treat ER+ ovarian cancers.”

— Monique Spillman, M.D., Ph.D., Gynecologic Oncologist, University of Colorado Hospital; Assistant Professor, Obstetrics & Gynecology, University of Colorado School of Medicine.

Spillman and her team now will begin to screen current anti-estrogen therapies against the newly identified ovarian cancer genes to identify the [biological] pathways and compounds relevant to the treatment for ER+ ovarian cancer.

This study looked at the effect of estrogen replacement therapy in mice that already possessed ER+ ovarian cancer cells. It did not test whether the estrogen replacement actually could cause the development of these cancer cells. The study also dealt only with estrogen replacement, which is linked to higher risks of ovarian cancer, not combined estrogen/progesterone therapy that is used with women who retain their uteruses.

This research is too early to draw implications for use of estrogen replacement therapy in women, Spillman cautions. “We cannot make clinical recommendations based on what is happening in mice,” says Spillman, one of just eight gynecological oncologists in Colorado. “Every woman is different and needs to talk to her doctor about the decision to use hormone replacement therapy.”

The study was funded by a Gynecologic Cancer Foundation Career Development Award and the Liz Tilberis Scholars Award from the Ovarian Cancer Research Foundation. This competitive award, a $450,000 three-year grant, is given to early-career researchers who are developing techniques for early diagnosis and improved care for women with ovarian cancer.

About the University of Colorado Cancer Center

The University of Colorado Cancer Center is the Rocky Mountain region’s only National Cancer Institute-designated comprehensive cancer center. NCI has given only 40 cancer centers this designation, deeming membership as “the best of the best.” Headquartered on the University of Colorado Denver Anschutz Medical Campus, UCCC is a consortium of three state universities (Colorado State University, University of Colorado at Boulder and University of Colorado Denver) and five institutions (The Children’s Hospital, Denver Health, Denver VA Medical Center, National Jewish Health and University of Colorado Hospital). Together, our 440+ members are working to ease the cancer burden through cancer care, research, education and prevention and control. Learn more at www.uccc.info.

Sources:

• Estrogen replacement therapy speeds ovarian cancer growth, new study reports, News Release, University of Colorado Denver, October 19, 2010.

• Spillman MA, Manning NG, Dye WW, et. al.  Tissue-Specific Pathways for Estrogen Regulation of Ovarian Cancer Growth and Metastasis. Cancer Res. 2010 Oct 19. [Epub ahead of print] PubMed PMID: 20959477.

Additional Information:

• Working Smarter, Not Harder: Use of Anti-Estrogen Therapy to Battle Recurrent Ovarian Cancer, by Paul Cacciatore, Libby’s H*O*P*E*, August 18, 2008.