The classification of lymphomas and leukemias

Targeting the actin nucleation promoting factor WASp provides a therapeutic approach for hematopoietic malignancies

Cancer cells depend on actin cytoskeleton rearrangement to carry out hallmark malignant functions including activation, proliferation, migration and invasiveness. Wiskott–Aldrich Syndrome protein (WASp) is an actin nucleation-promoting factor and is a key regulator of actin polymerization in hematopoietic cells. The involvement of WASp in malignancies is incompletely understood. Since WASp is exclusively expressed in hematopoietic cells, we performed in silico screening to identify small molecule compounds (SMCs) that bind WASp and promote its degradation. We describe here one such identified molecule; this WASp-targeting SMC inhibits key WASp-dependent actin processes in several types of hematopoietic malignancies in vitro and in vivo without affecting naïve healthy cells. This small molecule demonstrates limited toxicity and immunogenic effects, and thus, might serve as an effective strategy to treat specific hematopoietic malignancies in a safe and precisely targeted manner.

Cancer cells proliferate and invade via cytoskeletal proteins such as WASp, exclusively expressed in hematopoietic cells. Here the authors show a specific small molecule compound inhibiting cancer cell activity by WASp degradation and demonstrating its therapeutic potential in vitro and in vivo.

Prioritisation of treatment goals among older patients with non-curable cancer: the OPTion randomised controlled trial in Dutch primary care

BACKGROUND

Older patients with cancer often find it difficult to take part in shared decision making.

AIM

To assess the utility of the Outcome Prioritisation Tool (OPT), designed to aid discussion with a patient in regards to their treatment goals, to empower patients with cancer through structured conversations about generic treatment goals with GPs.

DESIGN AND SETTING

A randomised controlled trial of 114 Dutch participants recruited between November 2015 and January 2019, aged ≥60 years with non-curable cancer who had to make a treatment decision with an oncologist. The intervention group used the OPT while the control group received care as usual.

METHOD

The primary outcome was patient empowerment using the score on the decision self-efficacy (DSE) scale. Secondary outcomes were symptoms measures of fatigue, anxiety, and depression. The experiences of participants were also explored.

RESULTS

No effect was found on patient empowerment between the OPT group (n = 48; DSE 86.8; standard deviation [SD] = 18.2) and the control group (n = 58; DSE 84.2; SD = 17.6; P = 0.47). In the OPT group, although statistically non-significant, fewer patients had low empowerment (18.8%, n = 9 versus 24.1%, n = 14; P = 0.50), but they did have statistically significant lower mean anxiety scores (6.0, SD = 4.6 versus 7.6, SD = 4.4; P<0.05) and less mild fatigue (58.8%, n = 30 versus 77.2%, n = 44; P = 0.05). Overall, 44.8% (n = 13) of patients indicated that the OPT-facilitated conversation helped them make a treatment decision, and 31.1% (n = 14) of the GPs reported that they gained new insights from the conversation.

CONCLUSION

An OPT-facilitated conversation about generic treatment goals between patients and their GPs is associated with less anxiety and fatigue, but did not show statistically significant improvements in patient empowerment. Adding the OPT to routine care might ensure more patient-tailored care.

Neurologic aspects of lymphoma and leukemias

The lymphomas and leukemias are a heterogenous group of hematologic malignancies with protean manifestations. Neurologic sequelae of the diseases have been recognized since the time the conditions were first described in the mid-1800s. Although our understanding of the various presentations of these blood disorders evolved along with our knowledge of malignancies, accurate diagnosis can still be difficult. It is critical for neurologists to have a high index of clinical suspicion to appropriately recognize their heralding features. This review's focus is the relevant clinical neurologic features and diagnostic studies that identify leukemias and lymphomas affecting the nervous system.

Neurologic aspects of lymphoma and leukemias

The leukemias and lymphomas represent a heterogenous group of hematologic malignancies with protean manifestations. Neurologic sequelae of the diseases have been recognized almost since the time the conditions were first described in the mid-1800s. Although our understanding of the various presentations of these blood disorders has evolved along with our knowledge of the malignancies, accurate diagnosis can still be difficult. It is critical for neurologists to have a high index of clinical suspicion to appropriately recognize the heralding features. This review focuses on the relevant clinical neurologic features and diagnostic studies to identify leukemias and lymphomas affecting the nervous system.

Development of the Lymphoma Enterprise Architecture Database: a caBIG Silver level compliant system

Lymphomas are the fifth most common cancer in United States with numerous histological subtypes. Integrating existing clinical information on lymphoma patients provides a platform for understanding biological variability in presentation and treatment response and aids development of novel therapies. We developed a cancer Biomedical Informatics Grid™ (caBIG™) Silver level compliant lymphoma database, called the Lymphoma Enterprise Architecture Data-system™ (LEAD™), which integrates the pathology, pharmacy, laboratory, cancer registry, clinical trials, and clinical data from institutional databases. We utilized the Cancer Common Ontological Representation Environment Software Development Kit (caCORE SDK) provided by National Cancer Institute’s Center for Bioinformatics to establish the LEAD™ platform for data management. The caCORE SDK generated system utilizes an n-tier architecture with open Application Programming Interfaces, controlled vocabularies, and registered metadata to achieve semantic integration across multiple cancer databases. We demonstrated that the data elements and structures within LEAD™ could be used to manage clinical research data from phase 1 clinical trials, cohort studies, and registry data from the Surveillance Epidemiology and End Results database. This work provides a clear example of how semantic technologies from caBIG™ can be applied to support a wide range of clinical and research tasks, and integrate data from disparate systems into a single architecture. This illustrates the central importance of caBIG™ to the management of clinical and biological data.

SMI of Bcl-2 TW-37 is active across a spectrum of B-cell tumors irrespective of their proliferative and differentiation status

The Bcl-2 family of proteins is critical to the life and death of malignant B-lymphocytes. Interfering with their activity using small-molecule inhibitors (SMI) is being explored as a new therapeutic strategy for treating B-cell tumors. We evaluated the efficacy of TW-37, a non-peptidic SMI of Bcl-2 against a range spectrum of human B-cell lines, fresh patient samples and animal xenograft models. Multiple cytochemical and molecular approaches such as acridine orange/ethidium bromide assay for apoptosis, co-immunoprecipitation of complexes and western blot analysis, caspase luminescent activity assay and apoptotic DNA fragmentation assay were used to demonstrate the effect of TW-37 on different B-cell lines, patient derived samples, as well as in animal xenograft models. Nanomolar concentrations of TW-37 were able to induce apoptosis in both fresh samples and established cell lines with IC₅₀ in most cases of 165–320 nM. Apoptosis was independent of proliferative status or pathological classification of B-cell tumor. TW-37 was able to block Bim-Bcl-X_L and Bim-Mcl-1 heterodimerization and induced apoptosis via activation of caspases -9, -3, PARP and DNA fragmentation. TW-37 administered to tumor-bearing SCID mice led to significant tumor growth inhibition (T/C), tumor growth delay (T-C) and Log₁₀kill, when used at its maximum tolerated dose (40 mg/kg × 3 days) via tail vein. TW-37 failed to induce changes in the Bcl-2 proteins levels suggesting that assessment of baseline Bcl-2 family proteins can be used to predict response to the drug. These findings indicate activity of TW-37 across the spectrum of human B-cell tumors and support the concept of targeting the Bcl-2 system as a therapeutic strategy regardless of the stage of B-cell differentiation.

Chemiluminescent detection of clonal immunoglobulin and T cell receptor gene rearrangements in Tunisian lymphoid malignancies, leukemias and lymphomas

Clonal rearrangement of antigen receptor genes is commonly used to characterize the lymphoproliferative diseases. In order to perform molecular characterization in the diagnostics and monitoring of lymphoid malignancies, leukemias and lymphomas in Tunisia, we have introduced the use of chemiluminescent probes for immunoglobulin (IG) and T cell receptor (TR) gene rearrangement detection employing the Southern blot method. The chemiluminescent and radioactive detection methods tested with alkaline phosphatase and 32P labelled probes, respectively, were used for the IG and TR gene rearrangement characterization. Our results show the same pattern of rearrangement. Moreover, the chemiluminescent signal is detected faster and it is as sensitive as the radioactive one. We report the optimized conditions for using IGH, IGK, IGL, TRB and TRG probes in non radioactive detection. We have applied the chemiluminescent Southern blot method to analyze examples of Tunisian leukemias and lymphomas. The results allowed the assessment of clonality and the T or B cell lineage of these cases. The use of non radioactive probes makes chemiluminescent Southern blot detection reliable, safe and sensitive. As the use of radioactivity is not common in our laboratories and the licensing requirements needed for its use prohibitive, the chemiluminescent technique will be of great help for detection and characterization of molecular markers in lymphoid malignancies in Tunisia.

Comparative carcinogenicity of 1,3-butadiene, isoprene, and chloroprene in rats and mice

1,3-Butadiene, isoprene (2-methyl-1,3-butadiene), and chloroprene (2-chloro-1,3-butadiene) are high-production-volume chemicals used mainly in the manufacture of synthetic rubber. Inhalation studies have demonstrated multiple organ tumorigenic effects with each of these chemicals in mice and rats. Sites of tumor induction by these epoxide-forming chemicals were compared to each other and to ethylene oxide, a chemical classified by the National Toxicology Program (NTP) and by the International Agency for Research on Cancer (IARC) as carcinogenic to humans. For this group of chemicals, there are substantial species differences in sites of neoplasia; neoplasia of the mammary gland is the only common tumorigenic effect in rats and mice. Within each species, there are several common sites of tumor induction; these include the hematopoietic system, circulatory system, lung, liver, forestomach, Harderian gland, and mammary gland in mice, and the mammary gland and possibly the brain, thyroid, testis, and kidney in rats. For studies in which individual animal data were available, mortality-adjusted tumor rates were calculated, and estimates were made of the shape of the exposure-response curves and ED10 values (i.e. exposure concentrations associated with an excess risk of 10% at each tumor site). Most tumorigenic effects reported here were consistent with linear or supralinear models. For chloroprene and butadiene, the most potent response was for the induction of lung neoplasms in female mice, with ED10 values of 0.3 ppm. Based on animal cancer data, isoprene and chloroprene are listed in the NTP's Report on Carcinogens (RoC) as reasonably anticipated to be a human carcinogen. Butadiene is listed in the RoC as known to be a human carcinogen 'based on sufficient evidence of carcinogenicity from studies in humans, including epidemiological and mechanistic information', with support from experimental studies in laboratory animals. Epidemiology data for isoprene and chloroprene are not considered adequate to evaluate the potential carcinogenicity of these agents in humans.