Tag: T-cell lymphoma

Health Disparities and the Global Landscape of Lymphoma Care Today

The American Society of Clinical Oncology (ASCO) Annual Meeting brings together more than 30,000 oncology professionals each year to encourage discourse on leading research, state-of-the-art treatments, and ongoing controversies in the field. At this year’s Annual Meeting in Chicago, our own Dr. Adrienne Phillips was selected to present a review of the current health disparities in lymphoma care.

Adrienne Phillips

According to the National Institute on Minority Health and Health Disparities, health disparities are defined as “differences in incidence, prevalence, morbidity, mortality and burden of diseases and other adverse health conditions that exist among specific population groups.”

Dr. Phillips explained that health disparities may be due to a variety of factors, including race, gender, biology, and social and environmental differences such as socioeconomic status, health literacy, trust in the healthcare system, proximity to a healthcare facility, and access to and type of health insurance. For example, being uninsured or receiving government-assisted insurance increases patients’ risk of death by 1.5 times. Even patients’ place of residence may play a role, with treatment in rural, community-based settings being associated with inferior overall survival (OS) rates compared to treatment in urban, academic-based settings.

What Dr. Phillips and other physicians find most disconcerting about disparity in lymphoma care is that the disease is often amenable to effective therapy, but a significant segment of the population does not, or cannot, access appropriate care. For example, survival rates for some lymphomas skew lower for black people than for white people. Dr. Phillips conjectured that while African Americans tend to have poorer outcomes, the disparity is likely due to issues related to healthcare access and socioeconomic status.

According to an analysis of 701 people with diffuse large B-cell lymphoma (DLBCL) treated at two southern referral centers with a large black patient population (University of Alabama at Birmingham and Emory University in Atlanta), race did not influence outcomes. Black and white patients who received standard DLBCL chemotherapy drug combination rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine sulfate, and prednisone (R-CHOP) achieved similar OS rates (5y OS, 79% vs 70%).

Biological factors may also play a role in health disparities, and scientists are constantly working to better understand molecular factors in tumor development regardless of patient ethnicity.

In general, lymphoma is less common among African Americans and Asian Americans, but specific subtypes – like T-cell lymphoma in African Americans and natural killer T-cell (NKT) lymphoma in Asian Americans – are more common in these populations. Thus, Dr. Phillips highlighted a need for ethnic and racial diversity in clinical trial recruitment and in future studies of socioeconomic status and disease biology in order to better understand and improve outcomes for all patients.

Is Cutaneous T-Cell Lymphoma Hereditary?

Patients often question whether various lymphoma types run in families, concerned that their own diagnosis may indicate cancer risk for their loved ones, as well. When an inquiry regarding the possibility of genetic predisposition in cutaneous T-cell lymphoma (CTCL) recently came through our clinic, we sat down with expert Jia Ruan, MD, PhD, to break down what we know and what we don’t know about the cause of this rare and complex condition.Dr. Ruan at computer

T-cell lymphomas are a form of non-Hodgkin lymphoma caused by abnormal growth of mature T-cell lymphocytes, a type of white blood cell found in the immune system. In healthy people, T-cell lymphocytes are responsible for attacking foreign antigens and viruses, and aiding B-cell lymphocytes in antibody production – but by the process of clonal evolution, the T-cell lymphocytes mutate and produce abnormal offspring that become lymphoma. When T-cell lymphomas affect the skin, they are known as cutaneous T-cell lymphomas (CTCL).

The most common subtype of CTCL, mycosis fungoides (MF), occurs when malignant cells develop from CD4+CD45RO+ T-lymphocytes and migrate to the skin. Symptoms include scaly and itchy rash-like patches that may thicken over time and develop into a plaque or a tumor. If the cancer then makes its way from the skin to the lymphatic and blood system, MF becomes the more aggressive Sézary syndrome (SS). MF patients with limited skin symptoms do very well with skin-directed treatment, such as light therapy and topical medicines including steroids, while those with more extensive skin involvement or SS often require systemic treatment.

Although mycosis fungoides and Sézary syndrome are the most common types of cutaneous T-cell lymphoma, they are still quite rare, occurring in only 4-5 percent of non-Hodgkin lymphoma cases, with about 3,000 new diagnoses per year. The median age at diagnosis is 50-70, with a prevalence in men and African Americans.

It is in part due to their rarity that doctors and researchers have yet to understand what causes MF/SS. While there is no definitive evidence of familial risk of CTCL, scientists are continually evaluating whether genetics play a role in the disease formation.

Human leukocyte antigen (HLA) genes, which enable the immune system to discern between proteins native and foreign to the body, possess specific variations, or alleles, that are inherited via the family germline and passed through generations. When a certain HLA class II allele (specifically DQB1*04) was measured in a study of six families, each with occurrences of mycosis fungoides in two first-degree relatives, researchers found the allele to appear more frequently in patients than in the healthy control population, thus suggesting an association of the allele with familial MF. It is worth noting, however, that although some familial clusters of MF have been reported, the vast majority of CTCL cases occur without a familial link.

Additionally, deep genetic sequencing (whole exome) of mycosis fungoides samples, in which the patients’ DNA was analyzed to identify genetic variants, revealed recurrent mutations that seem to be acquired during a lifetime, rather than inherited – also known as somatic mutations. Somatic mutations are believed to be a leading factor in the unchecked cell division in most cancers. The examples of alterations included genes involved in: T-cell activation and programmed cell death (apoptosis), NF-κB signaling that plays a role in cell proliferation and survival, remodeling of chromatin (the DNA and proteins from which chromosomes are derived), and DNA damage response.

Without any strong scientific evidence of hereditary susceptibility, CTCL will likely continue to be thought of as an acquired disorder. Those with skin rash who are concerned about risk and family history are encouraged to see a dermatologist, who can refer to an oncologist or other specialist if the CTCL diagnosis is confirmed.

References:

Journal of the American Academy of Dermatology, 2005 Mar; 52: 393–402.

Nature Genetics, 2015 Sep; 47(9): 1011-9.

New Pre-clinical Research Shows Transcription-Targeting Drug Useful in T-cell Lymphoma

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.

tcell-lymphoma-graphic_cerchietti_thz1According 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.

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