Pretreating Aggressive Lymphoma With Targeted Therapy Improves Chemotherapy Effectiveness, Weill Cornell Medical College Study
8/16/2013 9:53:19 AM
Staying up-to-date has never been simpler. Sign up for the free GenePool newsletter today!
NEW YORK (August 16, 2013) -- Patients with an aggressive lymphoma that often relapses and kills within two years experienced a remission of their cancer and stayed disease-free as long as 28 months after taking a commercially-available drug that made chemotherapy more effective.
Researchers from Weill Cornell Medical College and NewYork-Presbyterian Hospital, who led the study published in Cancer Discovery, say their strategy has the potential to change the standard of care for patients with diffuse large B-cell lymphoma (DLBCL) -- and possibly other kinds of tumors.
The targeted drug they used, azacitidine, is designed to reawaken molecular mechanisms that typically trigger cell death but are switched off as cancer -- including lymphoma -- progresses. The research team discovered that pretreating aggressive lymphoma with azacitidine enables the death signal to turn back on when chemotherapy triggers it.
In a proof-of-concept, Phase 3 study of 12 high-risk DLBCL patients led by Dr. Peter Martin, assistant professor of medicine and a hematologist/oncologist at NewYork-Presbyterian Hospital/Weill Cornell Medical Center, 11 achieved a complete remission of their cancer, and 10 remained cancer-free for up to 28 months. The patients were given low doses of azacitidine for five days before standard chemotherapy was used.
"To have any hope for helping patients with aggressive lymphoma, we need to make this resistant cancer sensitive to treatment. We found we could do this by reprogramming the cancer to a more benign disease, which can then respond to chemotherapy," says the study's senior investigator, Dr. Leandro Cerchietti, the Sackler Scholar in Biomedical and Physical Sciences and assistant professor of hematology and oncology at Weill Cornell Medical College, who also collaborated with the Medical College's Dr. Ari Melnick, the Gebroe Professor of Hematology and Oncology and professor of medicine.
"In this remarkable study, Dr. Cerchietti discovered an important new disease mechanism that causes chemotherapy resistance in aggressive lymphomas, developed a new treatment regimen and completed the first clinical trial, demonstrating that his findings are true and directly relevant to those patients with the most severe forms of this tumor," Dr. Melnick says.
Approximately one-third of patients have DLBCL that either does not respond to initial chemotherapy or relapses after treatment. Because the majority of those patients will die within two years of their diagnoses, new treatments that will increase the time patients survive free of their disease are urgently needed, Dr. Cerchietti adds.
"By pretreating patients with a low-dose of azacitidine -- a targeted drug approved for use in myelodysplastic syndrome -- we achieved a profound and stable degree of reprogramming and chemosensitization that was very surprising to us," Dr. Cerchietti says.
"Oncologists have long believed that using high doses of an anti-cancer drug is the best strategy," he continues. "Our study shows that is not the case in this kind of lymphoma, and suggests this new approach can potentially be translated to other tumor types."
The researchers are expanding the study to additional DLBCL patients in a multi-center clinical trial that will soon enroll patients, and they also plan to study their pretreatment strategy in other tumor types, including additional lymphomas.
Failure at First, but Success After Understanding How the Drug Works
It took five years and collaborations with universities in Canada and Italy to translate laboratory findings to human cancer treatment. The clinical trial, and majority of cell and animal experiments, was conducted at Weill Cornell Medical College.
"This was truly a bench-to-bedside and back team effort, as being able to link the direct effects of azacitidine on primary tumor tissue from patients receiving the drug has allowed us to advance the epigenetic priming treatment strategy in a very precise fashion," says Dr. John Leonard, associate dean for clinical research and the Richard T. Silver Distinguished Professor of Hematology and Medical Oncology at Weill Cornell Medical College, and director of the Joint Clinical Trials Office at Weill Cornell Medical College and NewYork-Presbyterian Hospital.
The researchers studied azacitidine because of growing evidence that most cancers resist the killing powers of chemotherapy because of an inability to turn on cell death mechanisms. A major cause of this genetic resistance is the addition of silencing chemicals, called methyl groups, to death-inducing genes. These silencing chemicals prevent chemotherapy from activating the genes, making the treatment less effective. Azacitidine removes the methyl groups, allowing the chemotherapy drugs to activate these genes again and cause tumor cells to die.
But their early experiments were failures. Cell and animal studies demonstrated that powerful doses of azacitidine were not effective.
"We thought that maybe we were giving the drug in the wrong way, so we started doing experiments to see how it could work," Dr. Cerchietti says. "One of the first things we realized is that the drug has to be given in a concentration that will remove methyl groups without affecting other cellular processes.
"After that we investigated the genes and the pathways that were modified and were activated, and found that one important pathway that azacitidine could switch back on was the ability of the cell to die if its DNA was damaged -- which is what chemotherapy does," Dr. Cerchietti adds.
Successful animal experiments then led to studying the agent in newly diagnosed, previously untreated patients with aggressive DLBCL, many of whom likely had cancer that would not have responded to chemotherapy, he says.
"Elderly patients and patients with aggressive forms of lymphoma, such as those who participated in the clinical trial, have a higher chance of recurrence and less survival than younger patients," Dr. Cerchietti says. "They tend to have more chemo-resistant disease, which is why we focused our study on this population."
He added, "The worse the disease is, the higher the degree of aberrant methylation. In about 20 to 30 percent of patients, this aberrant methylation is associated with chemoresistance. Our pretreatment strategy reversed it."
"We are in the process of tailoring treatments to achieve a more personalized treatment, and we are very excited about the potential to help make chemotherapy and other treatments more beneficial for cancer patients," Dr. Cerchietti says.
This work was funded in part by grants LLS SCOR 7017-9, K08 CA127353, LLS 6304-11, NIH CA129831, CA129831-03S1, the Burroughs-Wellcome Foundation, the Chemotherapy Foundation, the V Foundation and the Charles, Lillian and Betty Neuwirth Clinical Scholar Award. Dr. Cerchietti is a Raymond and Beverly Sackler Scholar and scholar of the American Society of Hematology.
Study co-authors are Thomas Clozel, ShaoNing Yang, Rebecca L. Elstrom, Wayne Tam, Peter Martin, Matthias Kormaksson, Samprit Banerjee, Sarah Brennan, Michael Leser, Rita Shaknovich, John P. Leonard and Ari Melnick from Weill Cornell Medical College; Aparna Vasanthakumar and Lucy A. Godley from the University of Chicago; Biljana Culjkovic and Katherine Borden from the University of Montreal; David Scott and Randy Gascoyne from the British Columbia Cancer Agency, Vancouver; Amy Chadburn from Northwestern University; and Giorgio Inghirami and Fabrizio Tabbo from the University of Turin, Italy.
R.L. Elstrom is employed (other than primary affiliation; e.g., consulting) as medical director at Genentech, Inc., has received commercial research grants from Celgene and GlaxoSmithKline, has received honoraria from the speakers' bureaus of Seattle Genetics and Genentech, Inc. and is a consultant/advisory board member of Seattle Genetics. P. Martin and J.P. Leonard are consultant/ advisory board members of Celgene. A. Melnick has honoraria from the speakers' bureau of Genentech and is a consultant/advisory board member of Celgene and Bio-Reference Laboratories.
The Raymond and Beverly Sackler Center for Biomedical and Physical Sciences
The Raymond and Beverly Sackler Center for Biomedical and Physical Sciences of Weill Cornell Medical College brings together a multidisciplinary team of scientists for the purpose of catalyzing major advances in medicine. By harnessing the combined power of experimental approaches rooted in the physical and biological sciences, Sackler Center investigators can best accelerate the pace of discovery and translate these findings for the benefit of patients with various medical conditions, including but not limited to cancer.
Weill Cornell Medical College
Weill Cornell Medical College, Cornell University's medical school located in New York City, is committed to excellence in research, teaching, patient care and the advancement of the art and science of medicine, locally, nationally and globally. Physicians and scientists of Weill Cornell Medical College are engaged in cutting-edge research from bench to bedside, aimed at unlocking mysteries of the human body in health and sickness and toward developing new treatments and prevention strategies. In its commitment to global health and education, Weill Cornell has a strong presence in places such as Qatar, Tanzania, Haiti, Brazil, Austria and Turkey. Through the historic Weill Cornell Medical College in Qatar, the Medical College is the first in the U.S. to offer its M.D. degree overseas. Weill Cornell is the birthplace of many medical advances -- including the development of the Pap test for cervical cancer, the synthesis of penicillin, the first successful embryo-biopsy pregnancy and birth in the U.S., the first clinical trial of gene therapy for Parkinson's disease, and most recently, the world's first successful use of deep brain stimulation to treat a minimally conscious brain-injured patient. Weill Cornell Medical College is affiliated with NewYork-Presbyterian Hospital, where its faculty provides comprehensive patient care at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. The Medical College is also affiliated with the Methodist Hospital in Houston. For more information, visit weill.cornell.edu.
NewYork-Presbyterian Hospital, based in New York City, is the nation's largest not-for-profit, non-sectarian hospital, with 2,409 beds. The Hospital has nearly 2 million inpatient and outpatient visits in a year, including 12,758 deliveries and 215,946 visits to its emergency departments. NewYork-Presbyterian's 6,144 affiliated physicians and 20,154 staff provide state-of-the-art inpatient, ambulatory and preventive care in all areas of medicine at five major centers: NewYork-Presbyterian Hospital/Weill Cornell Medical Center, NewYork-Presbyterian Hospital/Columbia University Medical Center, NewYork-Presbyterian/Morgan Stanley Children's Hospital, NewYork-Presbyterian/The Allen Hospital and NewYork-Presbyterian Hospital/Westchester Division. One of the most comprehensive health care institutions in the world, the Hospital is committed to excellence in patient care, research, education and community service. NewYork-Presbyterian is the #1 hospital in the New York metropolitan area and is consistently ranked among the best academic medical institutions in the nation, according to U.S.News & World Report. The Hospital has academic affiliations with two of the nation's leading medical colleges: Weill Cornell Medical College and Columbia University College of Physicians and Surgeons. For more information, visit www.nyp.org.
Help employers find you! Check out all the jobs and post your resume.
comments powered by