Peripheral T-cell Lymphomas (PTCL) are uncommon, but aggressive forms of non-Hodgkin lymphoma that develop from mature T cells, a type of white blood cell. The most prevalent subtypes include PTCL-NOS (not otherwise specified), AITL (angioimmunoblastic T-cell lymphoma), and ALCL (anaplastic large cell lymphoma). Patients with PTCL are usually treated with a combination of chemotherapy agents, mostly commonly CHOP (cyclophosphamide, adriamycin, vincristine and prednisone). With the exception of a rare variant called ALK-positive ALCL, only about a third of all patients could enjoy long-term disease-free survival, with most patients either having diseases resistant to treatment or recurrent after chemotherapy. As PTCL evolves, it becomes even more molecularly complex due to factors in the tumor microenvironment that make it hard to treat. Ongoing research has been performed in order to try and improve treatment options and increase overall survival for patients with this challenging disease.
To ultimately cripple tumors in patients with PTCL and eradicate the disease from the body, it’s necessary to target the molecular feature of PTCL that helps it grow. Leandro Cerchietti, M.D. Jia Ruan, M.D., Ph.D., and other collaborators from the Lymphoma Program at Weill Cornell Medicine and NewYork-Presbyterian are trying to do just that. New research conducted by the team has shown positive results for this hard-to-treat cancer.
Dr. Cerchietti and his research group have discovered that PTCL are sensitive to THZ1, a drug that targets transcription, the first step during gene expression when DNA is copied into RNA. THZ1 was developed by Dr. Nathanael S. Gray and collaborators from the Dana-Farber Cancer Institute. THZ1 works by stopping an enzyme called CDK7 (cyclin-dependent kinase 7) that controls the transcription of lymphoma genes. This interference changes the cells and primes the tumor to better respond to biologic agents, such as BCL2 inhibitors.
For this work, Dr. Cerchietti’s Lab established a collaboration with Drs. Nathanael S. Gray from Dana-Farber and Graciela Cremaschi from the Institute for Biomedical Research and the National Research Council of Argentina. After testing more than 120 FDA-approved compounds and new biologic agents from the Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institutes of Health and the Meyer Cancer Center Pre-Clinical Oncology Pharmacy, the investigators found that PTCL are susceptible to inhibitors of the proteasome, epigenetic drugs and compounds that target transcription, like THZ1.
According to Cerchietti, they decided to focus on THZ1 since it demonstrated pre-clinical activity against PTCLs harboring the hard-to-target mutation STAT3. STAT can drive T-cell lymphomas and other tumors when activated by extracellular signaling that involves the phosphorylation of intermediate proteins like JAK. Although inhibitors of JAK proteins have been developed, they are thought to be inactive in tumors harboring the STAT3 mutation that does not require the activity of JAK. STAT proteins drive tumors by inducing the transcription of oncogenes like MYC and BCL2. Since this process requires CDK7, THZ1 can decrease the activity of STAT and the production of BCL2 and other proteins.
“Growing scientific evidence supports CDK7 inhibition as a treatment approach for cancers that are dependent on a high and constant level of transcription,” said Dr. Cerchietti. “Targeting CDK7 with THZ1 offers a way to circumvent the aggressive pathway responsible for tumor growth in many cancers, but particularly T-cell lymphomas which respond more positively to BCL2 inhibitors.”
BCL2 inhibitors are a class of drugs that are being tested to treat a variety of blood cancers. Venetoclax is an FDA-approved BCL2 inhibitor that is used to treat chronic lymphocytic leukemia (CLL) with a specific mutation.
“We are excited about these research results and the potential to bring a new treatment to patients with this aggressive lymphoma who otherwise have very few options if their cancer does not respond to chemotherapy,” said Dr. Ruan who leads the T-cell lymphoma clinical program at Weill Cornell Medicine and NewYork-Presbyterian.
“We aim to create transformative medicines that control the expression of disease-driving genes and believe this treatment can provide a profound and durable benefit for patients with a range of aggressive and difficult-to-treat solid tumors and blood cancers,” said Nancy Simonian, M.D., CEO of Syros, the biopharmaceutical company that is developing a next-generation version of the THZ1 compound for clinical trials. “Building on this research, we’ve used THZ1 as the starting point to create a selective CDK7 inhibitor that has better drug-like properties for use in humans.”
According to Syros, a phase I clinical trial built on this research is slated to open later this year to test the dosing and safety in people with solid tumors. The company plans to expand into hematological malignancies once the appropriate dose has been established in the initial phase I trial.
The bulk of this work was supported by the Leukemia and Lymphoma Society through a Translational Research Program awarded to Dr. Cerchietti.
Additional Weill Cornell Medicine contributors to this research include: Florencia Cayrol, Pannee Praditsuktavorn, Tharu Fernando, Rossella Marullo, Nieves Calvo-Vidal, Jude Phillip, Benet Pera, ShaoNing Yang, Kaipol Takpradit, Lidia Roman, Marcello Gaudiano, Ramona Crescenzo and Giorgio Inghirami.
Paola Ghione, MD
Dr. Ghione is a visiting hematology fellow from Torino, Italy who is working with the Weill Cornell Lymphoma Program for six months.
Minimal residual disease (MRD) detection refers to a group of techniques used to find a very small amount of disease, normally undetectable with imaging or clinical exam. Usually, this detection is performed after treatment and, in many cases, is predictive of outcomes such as whether patients will relapse, and how quickly this might happen. Often, the reappearance of MRD can anticipate recurrence of lymphoma before it becomes clinically evident. In other hematologic disorders, such as acute leukemia and chronic myeloid leukemia, MRD is used in standard clinical practice to monitor disease status or to evaluate response to treatment. In the setting of lymphoma, measurement of MRD is still considered experimental, but a lot of research is taking place around the world to find the best way to perform it.
Our laboratory in Torino, Italy, run by Dr. Marco Ladetto and Dr. Simone Ferrero, leads many MRD projects for lymphoma and is part of the EuroMRD Network, an institution born in Europe to standardize MRD techniques. Currently, we look for tumor-specific DNA alterations in the blood before and after treatment using a technique called Allele-Specific Oligonucleotide (ASO)-PCR. Depending on how much tumor DNA is present in the blood, we can figure out the relative amount of tumor left in the body. Unfortunately, ASO-PCR requires an expert laboratory team, and the method is expensive and time-consuming, which makes it hard to use outside of specialized settings. In addition, it seems more reliable if performed directly on bone marrow aspirate (blood from the interior of the bone) than peripheral blood (coming from a normal vein), making it less attractive to clinicians and people with lymphoma.
New techniques that can speed the procedure and reduce the cost are being evaluated. For example, the droplet digital (dd)-PCR is interesting because it is faster and uses less material (i.e., requires less blood for the test). Another interesting method is Next Generation Sequencing (NGS), which allows the detection of several different DNA mutations at once. NGS analysis of cell-free circulating DNA(cfDNA) (the DNA present in circulating blood outside the cells) could give a lot information. Studying cfDNA from the blood could give us a more accurate picture of the lymphoma that in theory could be even better than studying DNA derived from an open biopsy at one site of disease. This is also sometimes referred to as a liquid biopsy. The reason it might be better is that the circulating cfDNA could show us mutations coming from all the sites where the tumor is actively growing, not only the one site from which the open biopsy is taken.
In Italy, although MRD is not yet available in routine clinical practice for treating lymphoma, it is being tested in some innovative clinical trials to guide treatment decisions. In some studies MRD negativity at the end of treatment is the primary goal, while in others reappearance of MRD prompts a preemptive approach. As an example, if MRD reappears when the person is off therapy, we can give a short re-treatment in order to avoid clinical relapse. In one of our clinical trials, evaluation of MRD has been used to rule out the presence of lymphoma in the cells collected prior to autologous stem cell transplantation.
Measurement of MRD has a lot of potential uses, and experience from other diseases proves that it can be practice changing. The challenges provided by more than 50 different lymphoma subtypes as well as the rapid evolution of new laboratory techniques have delayed the adoption of a universal test for MRD. In the near future, however, we expect to see MRD analysis in standard clinical practice everywhere.
On January 19, 2017, the United States Food and Drug Administration (FDA) approved ibrutinib to treat patients that have received at least one line of prior therapy for marginal zone lymphoma (MZL), a type of non-Hodgkin lymphoma (NHL).
MZL is an indolent B-cell lymphoma that accounts for 5-10% of all lymphomas and lacks a standard of care. Current MZL treatments include anti-CD-20 antibody therapy (e.g. rituximab) or chemotherapy. However, ibrutinib is the first-ever treatment to specifically be approved for MZL.
Ibrutinib works by inhibiting Bruton’s tyrosine kinase (BTK), an enzyme responsible for transmitting pro-growth and survival signals from the surface of a cell to its nucleus. In this way, ibrutinib may interfere with chronic stimulation arising from inflammation in the tumor microenvironment; thus slowing the growth of B-cells.
The Weill Cornell Lymphoma Program is proud to have played a role in the phase 2 trial — the largest trial to date for people with previously treated MZL of all subtypes —leading to FDA approval for ibrutinib. Roughly half of all patients had a significant response to ibrutinib, with some degree of tumor shrinkage observed in almost 80% of all patients in the trial. Roughly one-third remained on treatment 18 months after beginning treatment.
The most common side effects included fatigue, diarrhea, and anemia. These side effects were manageable, and consistent with previous research, although some cases required the discontinuation of treatment with ibrutinib.
Results from this study support the use of ibrutinib as an effective well tolerated chemotherapy-free option for the treatment of previously treated MZL. However, some questions remain. MZL is a heterogeneous group of lymphomas, and it is unclear which subtypes might respond best to ibrutinib. With only half of all previously treated MZL patients responding to ibrutinib, improvements might be realized by combining ibrutinib with other drugs and/or using it earlier in the treatment of MZL.
At Weill Cornell, we are currently studying ibrutinib in combination with the immunotherapy drug durvalumab in people with previously treated indolent non-Hodgkin lymphoma, including MZL.
Recently researchers from Weill Cornell Medical College and Memorial Sloan Kettering Cancer Center discovered how a mutation in the KMT2D gene can drive the development of certain non-Hodgkin lymphomas. When properly functioning the gene KMT2D allows B-immune cells to generate antibodies against foreign objects in the blood stream. However, genetic mutations can disrupt normal immune cell growth, and prevent the proper functioning B-immune cells. Researchers found that,
“…normally KMT2D prepares key genes to respond to signals from other immune cells that stop B-cells, also called B-lymphocytes, from dividing and cause them to start making antibodies. However, when KMT2D mutations develop in B-cells, these external signals are no longer able to restrain them from dividing and stimulate their production of antibodies. As a result, there is an accumulation of rapidly dividing B-cells that eventually become malignant lymphomas. Importantly, the group demonstrated that therapies that have been developed to kill lymphoma cells by targeting these same signals are ineffective in the presence of KMT2D mutations.”
“KMT2D turns out to be one of the top 20 most mutated genes across all cancer types. It is really one of the superstars of cancer because it is one of the genes that is most strongly linked to tumors,” said co-senior author Dr. Ari Melnick, chair of the hematologic malignancies program in the Sandra and Edward Meyer Cancer Center and the Gebroe Family Professor of Hematology/Oncology at Weill Cornell Medical College. “Now that we understand how the gene functions in this treatment-resistant lymphoma, we can investigate the role of KMT2D mutations in other cancer types.”
These findings could potentially answer the question as to why certain lymphoma sub-types are treatment-resistant, while allowing for new avenues of therapeutic targeting.
In a recent study first published online, then as a plenary paper in the February 12 issue of Blood an inter-institutional team of researchers sequenced the genome of classical Hodgkin lymphoma (cHL). This sequencing allowed researchers to study the changes in proteins in individual patients, which could potentially lead to the development of new therapies targeting the cells affected by cHL. Their findings are especially notable as,
“Now we have a better idea of what mutations there are, and going forward therapies can be adapted to specific patient populations according to their genomic composition,” said senior author Dr. Ethel Cesarman, a professor of pathology and laboratory medicine at Weill Cornell Medical College.
Although scientists have sequenced the genomes of many other diseases, the cHL genome has remained elusive due to the difficulty of isolating Reed-Sternberg cells, which usually comprise less than 1 percent of a total cHL tumor. The team employed a technique that separates larger cells and looks at the proteins on their surface, called fluorescence-activated cell sorting, to successfully isolate the Reed-Sternberg cells and sequence the cancer genome, said senior author Dr. Mikhail Roshal, an assistant member in the Department of Pathology at Memorial Sloan Kettering Cancer Center.
These findings could potentially lead to more personalized treatment options for patients with cHL. They exemplify the bench to bedside approach taken by the Lymphoma Program and Meyer Cancer Center. Please look to this space for further updates about lymphoma news and clinical trials.
In our Frequently Asked Questions section, we previously addressed the question, “Can I take any nutritional supplements during chemotherapy?” by noting the potential beneficial and adverse effects that might arise from use of supplements, and by suggesting a candid discussion with treating physicians. However, the New York Attorney General recently noted that consumers of supplements have more than just medication interactions to be concerned about. Genetic testing of supplements sold at GNC, Target, Walgreens, and Walmart revealed that only 21% of supplements actually contained the herbal ingredient listed on the labels—at Walmart it was only 4%. Moreover, 35% of products tested contained DNA from plants not listed on the labels. Said Attorney General Schneiderman,
“The DNA test results seem to confirm long-standing questions about the herbal supplement industry. Mislabeling, contamination, and false advertising are illegal. They also pose unacceptable risks to New York families—especially those with allergies to hidden ingredients.”
These findings highlight an extraordinary lack of oversight in the supplement industry, which some manufacturers exploit routinely. We have therefore amended our FAQ section to include this potential concern, and we continue to advocate for open discussions between patients and physicians.
Earlier this week the FDA granted accelerated approval to palbociclib for the treatment of advanced (metastatic) breast cancer in combination with letrozole. Palbociclib selectively inhibits cyclin-dependent kinase 4 (CDK4) and 6 (CDK6), thereby suppressing tumor cell proliferation.
Over the past decade, researchers at Weill Cornell have led investigations of palbociclib in multiple myeloma and mantle cell lymphoma, including an ongoing phase I trial of palbociclib in combination with ibrutinib for patients with previously treated mantle cell lymphoma. Additional trials are planned.
Please look to this space for further updates concerning palbociclib for lymphoma patients. A full listing of available clinical trials can be found on our clinical trials page.