Efficacy and Safety of Blinatumomab for the Treatment of Relapsed/Refractory Acute Lymphoblastic Leukemia: A Systemic Review and Meta-Analysis

OBJECTIVE

The aim was to evaluate the efficacy and safety of blinatumomab monotherapy for the treatment of relapsed/refractory acute lymphoblastic leukemia (R/R B-ALL).

METHODS

PubMed, Embase, Web of Science, and Cochrane Library were searched to collect clinical studies related to blinatumomab. The primary outcome measures were complete remission (CR), and minimal residual disease (MRD) response. Prognostic indicators included overall survival (OS) and relapse-free survival time (RFS). Grade ≥3 adverse reactions were mainly analyzed for safety, including cytokine release syndrome (CRS), neurological events and hematological toxicity. The heterogeneity was quantified by I² statistic, which reflected the proportion of the true heterogeneity to the variance of the total effect size. Studies were considered heterogeneous if the I² statistic was greater than 50%, and conversely, studies were homogeneous.

RESULTS

A total of 18 studies involving 1,373 patients were included. The analysis results showed a CR rate of 54% (95%CI:44%-64%) and an MRD response rate of 43% (95%CI:34%-51%). The CR rate was higher in patients with bone marrow (BM) blast <50% than in patients with BM blast ≥50% (71% vs. 34%). The median OS and RFS were 8.16 months (95%CI:6.64-9.69) and 6.02 months (95%CI:4.63-7.41), respectively. For safety analysis, the incidence of grade ≥3 adverse events (AEs) was 80% (95%CI:72%-88%), the incidence of grade ≥3 neurological toxicity was 7% (95%CI:4%-11%), and the incidence of grade ≥3 CRS was 3% (95%CI:2%-5%). However, the mixture of retrospective and prospective studies led to heterogeneity to some extent in this meta-analysis.

CONCLUSION

Blinatumomab is effective in the treatment of R/R B-ALL with a controlled occurrence of AEs and a reliable safety profile.

Cytotoxic activity of standardized extracts, a fraction, and individual secondary metabolites from fenugreek seeds against SKOV-3, HeLa and MOLT-4 cell lines

CONTEXT

Trigonella foenum-graecum L. (Fabaceae) has many therapeutic properties and anticancer potential.

OBJECTIVE

The cytotoxic activities of standardized extracts and a fraction from fenugreek seeds and their compounds (sapogenins, flavone C-glycosides, alkaloid trigonelline) against human cancer SKOV-3, HeLa and MOLT-4 cells were evaluated.

MATERIALS AND METHODS

Fenugreek seeds were extracted with 70% methanol (A) or water (B). Furthermore, the seeds were purified with petroleum ether and chloroform and next extracted with methanol to obtain fraction (C). The quantitative analysis of saponins and flavonoids in the extracts was done with HPLC methods. The extracts (5-120 µg/mL) and compounds (1-50 µg/mL) were tested on the cells by MTT assay and RTCA system. The effect of a fraction on ROS production, mitochondrial membrane potential and caspase-3/7 activity in HeLa and SKOV-3 cells was also evaluated by flow cytometry.

RESULTS

The strongest cytotoxic activity on cancer cells showed the fraction C (IC₅₀ was 3.91 ± 0.03 for HeLa, 3.97 ± 0.07 for SKOV-3, and 7.75 ± 0.37 for MOLT-4) with the highest content of steroidal saponins (163.18 ± 11.03 μg/mg) and flavone C-glycosides (820.18 ± 0.05 μg/mg). The fraction significantly increased ROS production (up to four times higher than in keratinocytes as control) and caspases activity in the cells. The examined flavonoids did not exhibit the cytotoxic activity in contrast to yamogenin, tigogenin, and diosgenin.

CONCLUSIONS

The obtained results complement the data on the cytotoxic activity of Foenugraeci Semen and synergistic effect of flavonoids and saponins complex contained in the plant.

Case Report: Stepwise Anti-Inflammatory and Anti-SARS-CoV-2 Effects Following Convalescent Plasma Therapy With Full Clinical Recovery

In these times of COVID-19 pandemic, concern has been raised about the potential effects of SARS-CoV-2 infection on immunocompromised patients, particularly on those receiving B-cell depleting agents and having therefore a severely depressed humoral response. Convalescent plasma can be a therapeutic option for these patients. Understanding the underlying mechanisms of convalescent plasma is crucial to optimize such therapeutic approach. Here, we describe a COVID-19 patient who was deeply immunosuppressed following rituximab (anti-CD20 monoclonal antibody) and concomitant chemotherapy for chronic lymphoid leukemia. His long-term severe T and B cell lymphopenia allowed to evaluate the treatment effects of convalescent plasma. Therapeutic outcome was monitored at the clinical, biological and radiological level. Moreover, anti-SARS-CoV-2 antibody titers (IgM, IgG and IgA) and neutralizing activity were assessed over time before and after plasma transfusions, alongside to SARS-CoV-2 RNA quantification and virus isolation from the upper respiratory tract. Already after the first cycle of plasma transfusion, the patient experienced rapid improvement of pneumonia, inflammation and blood cell counts, which may be related to the immunomodulatory properties of plasma. Subsequently, the cumulative increase in anti-SARS-CoV-2 neutralizing antibodies due to the three additional plasma transfusions was associated with progressive and finally complete viral clearance, resulting in full clinical recovery. In this case-report, administration of convalescent plasma revealed a stepwise effect with an initial and rapid anti-inflammatory activity followed by the progressive SARS-CoV-2 clearance. These data have potential implications for a more extended use of convalescent plasma and future monoclonal antibodies in the treatment of immunosuppressed COVID-19 patients.

Mechanisms of Resistance to Monoclonal Antibodies (mAbs) in Lymphoid Malignancies

PURPOSE OF REVIEW

Passive immunotherapy with therapeutic monoclonal antibodies (mAbs) has revolutionized the treatment of cancer, especially hematological malignancies over the last 20 years. While use of mAbs has improved outcomes, development of resistance is inevitable in most cases, hindering the long-term survival of cancer patients. This review focuses on the available data on mechanisms of resistance to rituximab and includes some additional information for other mAbs currently in use in hematological malignancies.

RECENT FINDINGS

Mechanisms of resistance have been identified that target all described mechanisms of mAb activity including altered antigen expression or binding, impaired complement-mediated cytotoxicity (CMC) or antibody-dependent cellular cytotoxicity (ADCC), altered intracellular signaling effects, and inhibition of direct induction of cell death. Numerous approaches to circumvent identified mechanisms of resistance continue to be investigated, but a thorough understanding of which resistance mechanisms are most clinically relevant is still elusive. In recent years, a deeper understanding of the tumor microenvironment and targeting the apoptotic pathway has led to promising breakthroughs. Resistance may be driven by unique patient-, disease-, and antibody-related factors. Understanding the mechanisms of resistance to mAbs will guide the development of strategies to overcome resistance and re-sensitize cancer cells to these biological agents.

Targeted alpha therapy for chronic lymphocytic leukaemia and non-Hodgkin's lymphoma with the anti-CD37 radioimmunoconjugate 212Pb-NNV003

Relapse of chronic lymphocytic leukaemia and non-Hodgkin's lymphoma after standard of care treatment is common and new therapies are needed. The targeted alpha therapy with 212Pb-NNV003 presented in this study combines cytotoxic α-particles from 212Pb, with the anti-CD37 antibody NNV003, targeting B-cell malignancies. The goal of this study was to explore 212Pb-NNV003 for treatment of CD37 positive chronic lymphocytic leukaemia and non-Hodgkin's lymphoma in preclinical mouse models.An anti-proliferative effect of 212Pb-NNV003 was observed in both chronic lymphocytic leukaemia (MEC-2) and Burkitt's lymphoma (Daudi) cells in vitro. In biodistribution experiments, accumulation of 212Pb-NNV003 was 23%ID/g and 16%ID/g in Daudi and MEC-2 tumours 24 h post injection. In two intravenous animal models 90% of the mice treated with a single injection of 212Pb-NNV003 were alive 28 weeks post cell injection. Median survival times of control groups were 5-9 weeks. There was no significant difference between different specific activities of 212Pb-NNV003 with regards to therapeutic effect or toxicity. For therapeutically effective activities, a transient haematological toxicity was observed. This study shows that 212Pb-NNV003 is effective and safe in preclinical models of CD37 positive chronic lymphocytic leukaemia and non-Hodgkin's lymphoma, warranting future clinical testing.

The Role of PI3K Inhibition in Lymphoid Malignancies

PURPOSE OF REVIEW

The outcome of patients with lymphoid malignancies has markedly improved in recent years which is likely due to a combination of advances in supportive care, and therapeutic options. In this article, we will provide an overview over the role PI3-kinase signalling, one of the most important dysregulated pathways in cancer, and its successful inhibition in lymphoma.

RECENT FINDINGS

PI3-kinase inhibitors have shown remarkable activity in an increasing subset of patients with non-Hodgkin lymphomas. The first drug to be approved was idelalisib for patients with relapsed/refractory follicular lymphoma and CLL/SLL as monotherapy, or in combination with rituximab, respectively. After an initial setback related to increased toxicity including deaths observed in several upfront studies, there has been a resurgence in interest in this pathway following the promising efficacy of second-generation PI3K inhibitors including in patients with T cell lymphomas. PI3K inhibition continues to be an invaluable tool in the therapy of patients with lymphoid malignancies if managed cautiously. Preclinical models are helpful in predicting possible side effects and identifying new lymphoma subtypes that may be susceptible to this class of agents. The future will likely involve rationally designed combinatorial approaches to deepen the response rate and prevent the emergence of resistance.

Maximizing the effectiveness of oral therapies in lymphoid cancers: research gaps and unmet needs

Oral therapies have become a common treatment choice for several lymphoid cancers. While therapeutic efficacy and patient preference for this therapy type have been reported, there is a lack of knowledge about its effectiveness for lymphoma in clinical practice, particularly in regard to the effects of medication nonadherence. While studies of oral medications in other diseases have shown that adherence is a major factor in outcomes and costs, there is scant research investigating adherence specifically in lymphoma patients, who face unique challenges in their diseases and treatments. To address the limited data available, we constructed a conceptual model and highlighted key opportunities for future research to better elucidate oral therapy adherence in lymphoma. This research will hopefully improve understanding and efficacy of oral treatment for lymphoma patients, while also informing other cancers utilizing oral therapies currently and in the future.

Combined Use of Vinblastine and Vincristine in the Treatment of Tumors

A series of 70 patients with advanced incurable neoplasms, received a combined treatment with vinblastine (VLB) and vincristine (VCR). VLB was given at a dose of 7.5 to 10 mg and VCR at a dose of 0.75 to 1 mg. The two agents were administered intravenously at weekly intervals. Good remissions were obtained in patients with lymphoma and with mycosis fungoides. The best results were obtained in the cases of Hodgkin's disease. It is of interest that the combined treatment was effective in cases which had already become resistant or poorly responsive to various chemical agents including, in a few cases, the vinca alkaloids given separately.

Ataxia Telangiectasia and Acute Lymphoblastic Leukemia: Report of a Case

We report a new case of ataxia-telangiectasia (AT) and acute lymphoblastic leukemia (ALL) and review all 21 known cases of AT and ALL. Leukemia in these patients is associated with a male predominance, age older than 10 years at diagnosis, a white blood cell count higher than 50,000 mm3, and a fatal course. Four patients have been reported who developed T-cell leukemia, 3 null-cell leukemia and 1 B-cell leukemia. The AT-ALL patients appear to be at risk for infections related to their immunodeficient status and ALL chemotherapy. In addition, neurologic deterioration has been noted during the early phase of therapy.

Cytokinetic Studies in Acute Leukemia during Early Induction Therapy

The proliferative activity of bone marrow blasts was determined in 19 patients with acute leukemia during early induction therapy using in vitro tritiated thymidine (3H-TdR) cytoautoradiography and propidium iodide DNA flow cytofluorometry. Folloding 1-3 causes of treatment, the aliquot of bone marrow blasts in 9 patients, who later achieved remission or marrow aplasia, was reduced to a greater extent that of the remaining 10 patients who failed to respond. In the first group of patients, the 3H-TdR labeling index was increased by 259-653 % over the pretreatment value, whereas it was lower than 104 % of the pretreatment value in all but one unresponsive patient. Leukemic blast recruitment is conceivable. It might have facilitated remission by increasing the effectiveness of the antileukemic agents administered later.

Primary Malignant Neoplasms Associated with Chronic Lymphocytic Leukemia

Over the past 2 decades there has been an almost exponential increase in the frequency with which cases of leukemia associated with another primary malignant lesion have been reported. In this study we reported the occurrence of a second primary neoplasm in 82 consecutive cases of chronic lymphocytic leukemia (CLL) admitted to the Istituto Nazionale Tumori of Milan from September 1962 to December 1978. In 16 of these (19.5%), an associated neoplasm was diagnosed subsequently (8 cases) or concurrently (8 cases) to CLL. Head and neck carcinomas and breast cancer had the highest incidence (5 and 3 cases, respectively). The results of this study further support the hypothesis that patients with CLL are prone to develop subsequent cancer. The defective cellular and humoral immunity in CLL may have an etiological role in the development of an additional primary malignancy. Although alkylating agents are known carcinogens in experimental animals and man, our results support the lack of a correlation between treatment with alkylating agents and incidence of second primary neoplasms, as demonstrated by Greene et al. (10).

Cardiovascular Toxic Effects of VM 26 in the Treatment of Acute Lymphatic Leukemia. Presentation of Two Cases

Two cases of acute lymphatic leukemia treated with VM 26 underwent a severe cardiovascular syndrome with hypertension and cardiac failure. The first patient, a 9-year-old boy, after the appearance of hypertension suffered from serious cerebral hemorrhages which were lethal. The second patient, a 12-year-old boy, also developed hypertension with retinal hemorrhages and cardiac failure. Hypertension was, however, controlled, the patient recovered, and at present he is in remission. Although cardiovascular toxic effects are not frequent after administration of VM 26, they should be known to the medical oncologist so that treatment of this side effect may be introduced at the first appearance of the symptoms.

Polyamines as Biological Markers of the Effectiveness of Therapy in Acute Leukemia

Urinary polyamine levels were determined in patients with acute leukemia, before and during chemotherapy, in order to confirm whether tumor cell death, due to successful chemotherapy, increases the release in urine and serum of polyamines from tumor tissues (12). Comparison between the polyamine test and cytological data indicated that a rise in urinary spermidine levels occurs during the first 3 days of therapy, both in the responsive and unresponsive patients. However, in the responsive patients the spermidine increase was higher (at 5 % significant level) than in the unresponsive ones, and it was coincident with the fall of the blast cells and the revival of normal hematopoiesis. Increases in putrescine levels were also observed, but there were no significant differences (5 % level) between the 2 groups of patients. When polyamine determinations were carried out following chemotherapy cycles, the relapse of the disease was always accompanied by an increase in putrescine.

Lithium and Granulocytopenia during Induction Treatment of Adult Acute Lymphoblastic Leukemia

Twelve adult patients with acute lymphoblastic leukemia (ALL) received lithium carbonate, 300 mg, three times a day during induction treatment. They were compared to 12 similar patients consecutively treated with the same induction regimen; patients and controls were comparable for age, degree and presence of splenomegaly, hemoglobin level, blast cell count, polymorphonuclear (PMN) cell count and platelet count at diagnosis. All patients developed a severe neutropenia. PMN count at nadir was slightly higher in the lithium group, but not at a level of statistical significance (p = 0.100). The median number of days with PMN < 1 × 109/liter was 4 in the lithium group and 14.5 in the non-lithium group (p = 0.014), while the median number of days with PMN < 0.5 × 109/liter was 0 and 2 days, respectively (p = 0.004). Duration of thrombocytopenia was similar in the 2 groups and so was the remission rate; 2 infective episodes occurred, one in the lithium group and one in the controls.

Daunomycin Treatment in Chronic Lymphoproliferative Disorders

Daunomycin was administered to 16 patients with chronic lymphoproliferative disorders (10 with Stage IV lymphoreticular sarcomas and 6 with chronic lymphocytic leukemia). The age of subjects was ranging between 36 and 64 years (average 54 years). 8 out of 16 patients had been previously treated with radiotherapy and/or chemotherapy. The drug was injected intravenously at the initial dose of 0.6 mg/kg (7 cases), 0.8 mg/kg (8 cases) and 1 mg/kg (1 case) for 3–4 consecutive days. After 1 day interval, treatment was continued in most cases on alternate days schedule until signs of toxicity appeared. In some patients after the initial course the dose/kg was increased or decreased according to the peripheral blood picture. The total dose ranged between 2.2 to 13.3 mg/kg. In 7 patients prednisone (50 mg daily by mouth) was given in association to daunomycin (tables 1 and 2). Objective responses were seen in 5 out of 6 patients with chronic lymphocytic leukemia. While a consistent shrinkage of the nodes and especially of the spleen was observed in all responsive cases, the fall in the leukocyte level was mild and transient. In lymphoreticular sarcomas 5 out of 10 patients responded; the most significant regression was obtained in patients with splenomegaly, but also lymphonodes, hepatomegaly, pulmonary and cutaneous lesions responded. Two patients had also the bone marrow infiltrated with extrinsic cells: no significant changes were seen after treatment with 6 and 6.2 mg/kg. Regression usually occurred after few doses; nevertheless in all but one responsive patients they were incomplete. Maintenance treatment was then started with alkylating agents. The patients treated with daunomycin and prednisone did not show any better response than those treated with daunomycin alone. In 5 cases a sudden dyspnea, tachycardia and hypotension developed after different doses of daunomycin ranging from 2.2 to 8 mg/kg. Four patients died within 24 hours and one after 5 days from the beginning of symptoms. EKG abnormalities (tachicardia, flattening of ST and T waves) were recorded in all patients died with cardiac failure. In two cases the EKG changes appeared only after daunomycin administration while in three cases mild electric abnormalities present before the treatment got worse after few doses of daunomycin. Necroscopy was performed only in one case where besides superficial necrosis of the intestinal mucosa no specific alterations of the heart and vessels were seen. The conclusion is that daunomycin can produce rapid objective responses in chronic lymphoproliferative disorders, although the quality of these regressions in the majority of patients is insufficient to influence the natural course of the disease. Prolongued administration of the drug especially in patients previously treated with chemotherapy is not recommended because of the severe marrow depression. The so-called cardiac toxicity seems from this study to be dose-indipendent in patients with cardiovascular disease and EKG abnormalities before drug administration. Daunomycin therefore should not be given even in small dosage to patients with EKG abnormalities.

Preliminary Phase I Evaluation of Bleomycin, a New Antitumor Antibiotic

Bleomycin (BLM), a new antitumor antibiotic isolated in Japan from cultures of Streptomyces Verticillus, was administered by single intravenous injections to patients with different types of lymphomas and miscellaneous solid tumors for phase I evaluation. 85 out of the 110 patients included in the study were suitable for the evaluation of acute and delayed toxicity, while 93 patients were evaluable to detect the therapeutic effects of the drug. The average age of the patients was 54 years (range 7–83). 16 patients were untreated and 77 had received one or more courses of radiotherapy and/or chemotherapy. During this trial different doses and schedules were employed (table 2): A) 30 mg/m2 × 2/week × 4 weeks; B) 30 mg/m2/day × 8 days; C) 15 mg/m2/day × 8 days. After a month interval all 3 courses were repeated; D) 15 mg/m2/day × 5 days to be repeated twice after 3 weeks interval. Maintenance therapy consisted of 15–30 mg/m2/week. To diminish the febrile reaction, a suppository of indometacin (100 mg) was given 30–60 minutes prior to drug administration. The incidence of toxic manifestations, irrespective of dose and schedule, was as follows (fig. 4): sclerotic changes of the skin of hands (80%), fever (67%), alopecia (61 %), skin hyperpigmentation (60 %), stomatitis (48 %), gastrointestinal disturbances (20%) and pulmonary symptoms (19%). No definite signs of marrow toxicity nor significant changes in the blood chemistry attributable to the drug were observed. Symptoms and signs of pulmonary toxicity, appearing 1–4 weeks after the last dose were: rhonchi, rales and pleural friction rubs, in some cases associated with fever and dyspnea. The chest X-ray showed evidence of interstitial lesions (in early phases most marked at the costophrenic angle) which may become widespread with a bronchopneumonia-like appearance (fig. 5 and 6). No clearcut radiological signs of pulmonary fibrosis were observed (patients were not followed for a period longer than 5 months). If BLM is stopped in time and carticosteroids are given in association to antibiotics, both clinical and radiological findings may disappear completely (fig. 7). Of the 7 patients studied post mortem, 6 revealed lesions attributable to drug toxicity (alveolar collapse with edema, histiocytic proliferation, hyaline membranes, alveolar and interstitial fibrosis (fig. 8–11). In 7 patients pulmonary toxicity was suspected only on clinical grounds, in 2 cases the radiological aspect of the lungs was suggestive of interstitial lesions without concomitant physical findings, in 9 cases a good correlation between clinical and radiological diagnosis was observed and, finally, in 6 patients the pulmonary fibrosis was detected on histological examination (table 3). In the 17 patients in whom the diagnosis of pulmonary toxicity was documented either radiologically or histologically, the average age was 56,5 years (7–78 years) and the mean total dose, producing toxicity was 230 mg/m2 (range 60–480). Practically, all these patients prior to the treatment had different grades of chronic pulmonary lesions (emphysema, fibrosis post RT or tuberculosis, silicosis in 1 case). It is difficult to estimate in what proportion BLM could have contributed to the cause of death, since most patients dying during treatment had also lung metastases. However, at least in 1 case in whom postmortem examination did not disclose lymphosarcoma cells (complete remission), the cause of death could be related to drug administration (total 225 mg/m2) since extensive pulmonary fibrosis was seen on histological examination (table 4). Table 5 shows the incidence of side-effects after the first course of BLM. No significant differences were observed among cases treated with 4 different schedules, and the first sign of toxicity appeared in all groups after the 4th–6th dose irrespective of the dose and schedule. Regressions in different types of tumors were observed during this phase I study (table 6). The overall regression rate was 69 % (24 % greater than 50 % and 5% complete). The therapeutic response was prompt but usually short-lived (average 4–6 weeks). No cross-resistance with radiotherapy nor with some of the conventional agents was observed. The most responsive tumors were carcinomas of head and neck, carcinomas of esophagus (fig. 17) and malignant lymphomas (fig. 16). One 7-year-old boy with acute lymphosarcoma cell leukemia had a complete remission and autopsy revealed no signs of neoplastic disease. In 2/3 patients with CLL a moderate decrease in the volume of hepato-splenomegaly was observed without significant fall in the WBC. The minimal toxic dose was 45–60 mg/m2 in malignant lymphomas and 60–120 mg/m2 in the other solid tumors. BLM appears to be a potent new growth-inhibiting compound specific for epidermoid carcinomas and devoid of bone marrow toxicity. The optimal dose schedule as well as the real incidence and course of pulmonary toxicity should be more clearly defined in future studies.

PRES in the course of hemato-oncological treatment in children

INTRODUCTION

Posterior reversible leukoencephalopathy syndrome (PRES) is a clinical syndrome of varying aetiologies, characterised by acute neurological symptoms of brain dysfunction with MRI abnormalities in posterior cerebral white and grey matter. In most cases, symptoms resolve without neurological consequences.

AIM

The aim of this paper is the analysis of predisposing factors, clinical outcomes and radiological features of PRES in eight children with hemato-oncological disease.

MATERIAL AND METHODS

We analysed the medical records of eight hemato-oncological patients aged from 3.0 to 16.1 years. The mean of age at primary diagnosis was 8.5 years.

RESULTS

All patients had both clinical and radiological PRES features. Seven out of eight underwent intensive chemotherapy regimens. Time elapsed from start of treatment to the occurrence of PRES ranged from 6 to 556 days. In one case, PRES occurred before chemotherapy and was the first symptom of cancer. Most (six of eight) patients had history of hypertension (> 95pc) and some (two of eight) occurred electrolyte imbalance-mainly hypomagnesaemia. Patients presented headache (seven of eight), disturbances of consciousness (six of eight), seizures (six of eight), visual changes (four of eight) and vomiting (three of eight). MRI demonstrated abnormalities in seven children: typical cerebral oedema in the white matter of the occipital to the parietal lobes. Most patient lesions in the MRI shrunk after 4 weeks, and clinical symptoms of PRES disappeared completely within a few hours to few days.

CONCLUSION

PRES may complicate oncological treatment in children. Hypertension is the most important risk factor of PRES. PRES should be included in differential diagnosis in all patients with acute neurological symptoms.

ABT-199 (venetoclax) and BCL-2 inhibitors in clinical development

With the advent of new agents targeting CD20, Bruton's tyrosine kinase, and phosphoinositol-3 kinase for chronic lymphoid leukemia (CLL), more treatment options exist than ever before. B-cell lymphoma-2 (BCL-2) plays a major role in cellular apoptosis and is a druggable target. Small molecule inhibitors of BCL-2 are in active clinical studies. ABT-199 (venetoclax, RG7601, GDC-0199) has been granted breakthrough designation by FDA for relapsed or refractory CLL with 17p deletion. In this review, we summarized the latest clinical development of ABT-199/venetoclax and other novel agents targeting the BCL-2 proteins.

Akacid medical formulation induces apoptosis in myeloid and lymphatic leukemic cell lines in vitro and in vivo

Akacid medical formulation (AMF) is an oligoguanidine that exerts biocidal activity against airborne and surface microorganisms including bacteria, viruses, fungi, and molds, while showing relatively low toxicity to humans. We have previously shown that AMF exerts antiproliferative effects on a variety of solid tumor cell lines. In this study we raised the question whether AMF could also substantially inhibit cell growth or induce apoptosis in cell lines derived from hematologic malignancies such as leukemia or lymphoma. We found that AMF has antiproliferative effects on various hematologic cell lines derived from human leukemia and lymphoma. Additionally, we show that AMF induces apoptosis in leukemia cell lines not only via the extrinsic and intrinsic pathway, but also in a caspase-independent manner. This effect was found also in G0-arrested cells. Finally, in our animal experiments utilizing male nu/nu Balb/c mice we found a significant growth retardation, which was immunohistochemically associated with a significantly lower number of KI67-positive cells and caspase-3 induction in AMF-treated mice.

The long journey of TCL1 transgenic mice: lessons learned in the last 15 years

The first transgenic mouse of the TCL1 oncogene was described more than 15 years ago, and since then, the overexpression of the gene in T- and B-cells in vivo has been extensively studied to reveal the molecular details in the pathogenesis of some lymphocytic leukemias. This review discusses the main features of the original TCL1 models and the different lines of research successively developed with particular attention to genetically compound mice and the therapeutic applications in drug development.

Pharmacologic blockade of JAK1/JAK2 reduces GvHD and preserves the graft-versus-leukemia effect

We have recently reported that interferon gamma receptor deficient (IFNγR-/-) allogeneic donor T cells result in significantly less graft-versus-host disease (GvHD) than wild-type (WT) T cells, while maintaining an anti-leukemia or graft-versus-leukemia (GvL) effect after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We demonstrated that IFNγR signaling regulates alloreactive T cell trafficking to GvHD target organs through expression of the chemokine receptor CXCR3 in alloreactive T cells. Since IFNγR signaling is mediated via JAK1/JAK2, we tested the effect of JAK1/JAK2 inhibition on GvHD. While we demonstrated that pharmacologic blockade of JAK1/JAK2 in WT T cells using the JAK1/JAK2 inhibitor, INCB018424 (Ruxolitinib), resulted in a similar effect to IFNγR-/- T cells both in vitro (reduction of CXCR3 expression in T cells) and in vivo (mitigation of GvHD after allo-HSCT), it remains to be determined if in vivo administration of INCB018424 will result in preservation of GvL while reducing GvHD. Here, we report that INCB018424 reduces GvHD and preserves the beneficial GvL effect in two different murine MHC-mismatched allo-HSCT models and using two different murine leukemia models (lymphoid leukemia and myeloid leukemia). In addition, prolonged administration of INCB018424 further improves survival after allo-HSCT and is superior to other JAK1/JAK2 inhibitors, such as TG101348 or AZD1480. These data suggest that pharmacologic inhibition of JAK1/JAK2 might be a promising therapeutic approach to achieve the beneficial anti-leukemia effect and overcome HLA-barriers in allo-HSCT. It might also be exploited in other diseases besides GvHD, such as organ transplant rejection, chronic inflammatory diseases and autoimmune diseases.

[Molecular targeted therapy in lymphoid leukemias]

Recent advances in the treatment of lymphoid leukemias have incorporated molecular targeted drugs (CD20-targeting rituximab and BCR-ABL tyrosine kinase inhibitors) into the traditional chemotherapeutic agents. This article reviews novel molecular targeted therapies for patients with lymphoid leukemias including acute lymphoblastic leukemia, chronic lymphocytic leukemia, hairly cell leukemia and HTLV-I-related adult T-cell leukemia. Investigational agents that will be discussed in this review include inotuzumab, blinatumomab, alemtuzumab, ofatumumab, ibrutinib, idelalisib, bafetinib, lenalidomide, ABT-199 and mogamulizumab. Novel approaches warrant continued research to improve outcomes for patients with lymphoid leukemias.

Pharmacological and molecular effects of platinum(II) complexes involving 7-azaindole derivatives

The in vitro antitumour activity studies on a panel of human cancer cell lines (A549, HeLa, G-361, A2780, and A2780R) and the combined in vivo and ex vivo antitumour testing on the L1210 lymphocytic leukaemia model were performed on the cis-[PtCl₂(naza)₂] complexes (1–3) involving the 7-azaindole derivatives (naza). The platinum(II) complexes showed significantly higher in vitro cytotoxic effects on cell-based models, as compared with cisplatin, and showed the ability to avoid the acquired resistance of the A2780R cell line to cisplatin. The in vivo testing of the complexes (applied at the same dose as cisplatin) revealed their positive effect on the reduction of cancerous tissues volume, even if it is lower than that of cisplatin, however, they also showed less serious adverse effects on the healthy tissues and the health status of the treated mice. The results of ex vivo assays revealed that the complexes 1–3 were able to modulate the levels of active forms of caspases 3 and 8, and the transcription factor p53, and thus activate the intrinsic (mitochondrial) pathway of apoptosis. The pharmacological observations were supported by both the histological and immunohistochemical evaluation of isolated cancerous tissues. The applicability of the prepared complexes and their fate in biological systems, characterized by the hydrolytic stability and the thermodynamic aspects of the interactions with cysteine, reduced glutathione, and human serum albumin were studied by the mass spectrometry and isothermal titration calorimetric experiments.

An intact immune system is required for the anticancer activities of histone deacetylase inhibitors

Cell-intrinsic effects such as induction of apoptosis and/or inhibition of cell proliferation have been proposed as the major antitumor responses to histone deacetylase inhibitors (HDACi). These compounds can also mediate immune-modulatory effects that may contribute to their anticancer effects. However, HDACi can also induce anti-inflammatory, and potentially immunosuppressive, outcomes. We therefore sought to clarify the role of the immune system in mediating the efficacy of HDACi in a physiologic setting, using preclinical, syngeneic murine models of hematologic malignancies and solid tumors. We showed an intact immune system was required for the robust anticancer effects of the HDACi vorinostat and panobinostat against a colon adenocarcinoma and two aggressive models of leukemia/lymphoma. Importantly, although HDACi-treated immunocompromised mice bearing established lymphoma succumbed to disease significantly earlier than tumor bearing, HDACi-treated wild-type (WT) mice, treatment with the conventional chemotherapeutic etoposide equivalently enhanced the survival of both strains. IFN-γ and tumor cell signaling through IFN-γR were particularly important for the anticancer effects of HDACi, and vorinostat and IFN-γ acted in concert to enhance the immunogenicity of tumor cells. Furthermore, we show that a combination of vorinostat with α-galactosylceramide (α-GalCer), an IFN-γ-inducing agent, was significantly more potent against established lymphoma than vorinostat treatment alone. Intriguingly, B cells, but not natural killer cells or CD8(+) T cells, were implicated as effectors of the vorinostat antitumor immune response. Together, our data suggest HDACi are immunostimulatory during cancer treatment and that combinatorial therapeutic regimes with immunotherapies should be considered in the clinic.

Telomerase contributes to fludarabine resistance in primary human leukemic lymphocytes

We report that Imetelstat, a telomerase inhibitor that binds to the RNA component of telomerase (hTR), can sensitize primary CLL lymphocytes to fludarabine in vitro. This effect was observed in lymphocytes from clinically resistant cases and with cytogenetic abnormalities associated with bad prognosis. Imetelstat mediated-sensitization to fludarabine was not associated with telomerase activity, but with the basal expression of Ku80. Since both Imetelstat and Ku80 bind hTR, we assessed 1) if Ku80 and Imetelstat alter each other's binding to hTR in vitro and 2) the effect of an oligonucleotide complementary to the Ku binding site in hTR (Ku oligo) on the survival of primary CLL lymphocytes exposed to fludarabine. We show that Imetelstat interferes with the binding of Ku70/80 (Ku) to hTR and that the Ku oligo can sensitize CLL lymphocytes to FLU. Our results suggest that Ku binding to hTR may contribute to fludarabine resistance in CLL lmphocytes. This is the first report highlighting the potentially broad effectiveness of Imetelstat in CLL, and the potential biological and clinical implications of a functional interaction between Ku and hTR in primary human cancer cells.

Anti-tumor and pro-apoptotic activity of ethanolic extract and its various fractions from Polytrichum commune L.ex Hedw in L1210 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Polytrichum commune L.ex Hedw is a traditional Chinese herb for treatment of fever, hemostatic, uterine prolapse and especially for lymphocytic leukemia, but the antitumor effect and its potential mechanism remains unclear.

AIMS OF THE STUDY

The present study was to investigate the possible anti-proliferative activity of ethanolic extract and the organic fractions from P. commune on murine leukemia L1210 cells.

MATERIALS AND METHODS

The content of ethanolic extract and its fractions was performed on HPLC analysis with gradient elution. L1210 cells were treated with different concentrations of ethanolic extract and its fractions at different time intervals. Cell viability was evaluated using MTT assay. Apoptotic cell death was monitored by nuclear condensation and confirmed by exposure of phosphatidylserine to outer leaflet of plasma membrane. Loss of mitochondrial membrane potential was analyzed by flow cytometry using rhodamine 123 staining.

RESULTS

The obtained results showed that the cell viability of L1210 cells was reduced by ethanolic extract of P. commune in a concentration-dependent manner, and the IC(50) value was about 77.22 μg/ml at 24h post treatment. The ethylacetate fraction displayed higher anti-tumor effect than that of chloroform and butanol fractions with 32.29 μg/ml (IC(50) value, 48 h). Microscopy studies revealed that ethanolic extract and ethylacetate fraction treated cells showed morphological characteristics of apoptosis such as chromatin condensation and DNA aggregation. Further, Annexin V-PE/ 7-AAD double staining showing the out leaflet of phosphatidylserine and the decline of mitochondrial membrane potential by flow cytometry confirmed that the extracts do, in fact, induce apoptosis in L1210 cells.

CONCLUSION

This is the first report on anti-tumor and pro-apoptotic effect of P. commune in cultured leukemia cells, which provides scientific basis for its usefulness as traditional medicine. Further studies are needed to confirm the precise mechanism not only the crude extract but as well the monomeric chemical substances of Polytrichum commune L.ex Hedw.

A possible role for oxidation stress in lymphoid leukaemias and therapeutic failure

The aim of this study was to evaluate the role of oxidative stress in the pathobiology of lymphoid leukaemias and its involvement in leukaemic relapse. For this purpose the generation of peroxides by mononuclear cells, the erythrocyte activity of superoxide-dismutase (SOD) and glutathione peroxidase (GL-PX), and the plasma levels of reduced glutathione (GSH) and vitamin E (VIT E) were determined in 52 patients with two different types of lymphoid leukaemias, chronic lymphocytic leukaemia (CLL) and acute lymphoblastic leukaemia (ALL), 36 prior to chemotherapy and 16 treated patients. A decrease in SOD and GL-PX activities was observed in ALL patients prior to therapy, while a decrease in GSH and VIT E plasma levels was observed in untreated CLL, as compared to age-matched controls. An increase in peroxides formation occurred in both types of leukaemia, as compared to age-matched controls. There are significant differences for GSH, VIT E and peroxides generation between the different types of leukaemias. In relapsed ALL patients a decrease in peroxides generation was observed which may be due to the increase of the non-enzymatic defences GSH and VIT E. These data suggest the involvement of oxidative stress in acute and chronic lymphoid leukaemias and leukaemic relapse.

Assessment of peripheral blood and bone marrow cells apoptosis caused by purine analogues in patients with chronic lymphocytic leukemia in correlation with parameters of disease progression

Chronic lymphocytic leukemia (CLL) is a heterogeneous disease with variable clinical course and prognosis. Therefore, the role of prognostic factors is very important, especially for identifying the group of patients who require intensive treatment. The aim of this study was to assess whether the rate of apoptosis caused by purine analogues differs between patients with better or worse prognostic factors. The experiments were preformed in cultures of blood and bone marrow obtained from CLL patients. The cultures were supplemented with cladribine and fludarabine. We determined the percentage of caspase-3-positive cells and the BCL-2/BAX ratio, and subsequently these apoptosis markers were correlated with the expression of ZAP-70 and CD38, lymphocyte counts, lactate dehydrogenase and beta(2)-microglobulin levels and clinical stage according to the Rai classification. The results showed that bone marrow cells are more sensitive to apoptosis caused by purine analogues than cells derived from blood, supporting the idea that these two compartments have different proliferative statuses. The cells from ZAP-70-positive patients seem to enter apoptosis more readily than those from ZAP-70-negative patients; thus, ZAP-70-positive patients are more likely to benefit from treatment with purine analogues.

CD52 expression in T-cell large granular lymphocyte leukemia – Implications for treatment with alemtuzumab

Few reports on the successful treatment of T-cell large granular lymphocyte (LGL) leukemia with the humanized anti-CD52 monoclonal antibody alemtuzumab are emerging in the literature. The expression of CD52 by LGLs has not been previously investigated. Using semi-quantitative 2- and 3-color flow cytometry, we documented the expression of CD52 in 100% of abnormal cells in T-cell LGL leukemia (n = 11) and natural killer (NK) cell LGL leukemia (n = 2), and showed no significant difference in CD52 expression between T-cell prolymphocytic leukemia (PLL) and T-cell LGL leukemia. Higher CD52 expression has been noted in responders to alemtuzumab in T-cell PLL and in chronic lymphocytic leukemia (CLL), a B-cell disorder. The strong and consistent expression of CD52 shown here highlights the potential role of alemtuzumab in the treatment of refractory T-cell LGL leukemia and possibly aggressive NK cell leukemia.

Release and clinical significance of soluble CD83 in chronic lymphocytic leukemia

Soluble CD83 (sCD83), a potent immunosuppressive agent, circulates at elevated levels in some chronic lymphocytic leukemia (CLL) patients. We report that CLL patients with elevated plasma sCD83 levels had significantly shorter (P=0.038) treatment free survival. Culture of CLL cells with solid phase CD83 mAb+IL-4 significantly increases sCD83 release (23-117-fold, P=0.013) and ligation of normal donor PBMC with solid phase CD83 mAb alone induces similar significant increases in sCD83 release (P=0.003). RT-PCR analysis detected the presence of a transcript for sCD83 in 2/3 CLL samples. These results suggest sCD83 release may play a regulatory role in CLL progression.

The tyrosine kinase inhibitor AMN107 (Nilotinib) exhibits off-target effects in lymphoblastic cell lines

The aminopyrimidine inhibitor AMN107 (Nilotinib) was rationally designed to antagonize the aberrant tyrosine kinase activity of Bcr-Abl-positive cells. We here evaluated, whether AMN107 is also able to induce apoptosis in Bcr-Abl-negative cells of lymphatic origin. The B-cell lines DOHH-2 and WSU-NHL and the T-cell lines Jurkat and HUT78 were incubated with increasing amounts of AMN107 corresponding to clinically achievable dosages. Subsequently, induced molecular changes were assessed by FACS analysis, Western blot, and enzyme activity assays. Although AMN107 exhibited only a minor apoptosis-inducing effect in the T-cell lines, it exerted a considerable, dose-dependent cytotoxicity in the B-cell lines. Using selective caspase-inhibitors, we show that apoptosis in responder cell lines critically relies on activation of caspase-6 and caspase-9. Cell lines sensitive and resistant towards AMN107 can be discriminated by their differential expression of Src-kinases. Although the AMN107-sensitive cell lines DOHH-2 and WSU-NHL exhibited low or no expression of the Src-kinases Lck, phosphorylated Lck, and Yes with a concomitant high expression of Hck, Lyn, and phosphorylated Lyn, the expression pattern of these kinases was inverse in the AMN107-resistant T-cell lines. In conclusion, this is the first report providing evidence that activity of AMN107 is not restricted to Bcr-Abl, c-Kit, or PDGFR-positive cells, but also extends to lymphatic cell lines of B-cell origin.

Sequential application of chemotherapy and monoclonal CD 20 antibody: Successful treatment of advanced composite-lymphoma

We describe successful treatment of a 38-year-old patient with composite lymphoma stage IV(A), who presented with multifocal enlarged lymph nodes. The lymph node histology showed classic morphologic features of Hodgkin's disease, mixed cellularity subtype and follicular B-cell lymphoma. Immunophenotypic analysis showed immunoreactivity for CD20, CD10 and Ki-67 in the malignant small cell population. The areas of Hodgkin's disease demonstrated positive immunoreactivity for CD30 and CD20 in the Hodgkin's cells. Both cell populations were bcl2-oncoprotein positive. Eight courses of dose-escalated BEACOPP were administered. Restaging after chemotherapy showed radiological partial remission, but biopsy confirmed persisting follicular B-cell lymphoma without bone marrow infiltration and no evidence of Hodgkin's disease. He was treated with monoclonal CD 20-antibody (Rituximab) 10 mg/kg weekly for eight consecutive weeks due to marked positivity of CD 20-antigen in follicular lymphoma cells. This treatment was well tolerated and final staging showed complete remission of the composite lymphoma. This patient continues to be in remission 28 months after the end of the treatment. In conclusion, in the very rare case of composite lymphoma a combination of chemotherapy and subsequent immunotherapy might be considered as a promising therapeutic option.

Antipyretic effect of indomethacin in malignant lymphoma

Fifteen patients with lymphoid malignancies and tumour-related fever (greater than 38.0 degrees C) were given 50 mg indomethacin (IM) orally. This resulted in a reduction of body temperature in all cases (mean +/- SD 3.4 +/- 2.0 degrees C). In one patient with untreated Hodgkin's disease, temperature fell from 40.6 degrees C to 30.6 degrees C within 12 hours without any cardiovascular or respiratory distress. The lytic effect of IM on fever was more pronounced and more rapid in the 15 patients with lymphoma than in a group of 10 patients with acute myocardial infarction. IM therapy has a clear value in relieving tumour-associated fever in patients with malignant lymphoma. There may be a qualitative difference between the IM response of tumour-related fever and fever related to non-malignant diseases.

Clinical trial of prednimustine, Leo-1031 (NSC-134087), in patients with non-Hodgkin lymphomata and chronic lymphocytic leukaemia previously treated with steroids and alkylating agents

Prednimustine, a chlorambucil ester of prednisolone, was administered to 16 patients with non-Hodgkin lymphomata (NHL) and 14 patients with chronic lymphocytic leukaemia (CLL), all previously treated with steroids and alkylating agents. Response was obtained in 8 patients with NHL and 11 patients with CLL. Two NHL patients had long-lasting complete remissions. Median duration of response for lymphomata was 12 weeks, for CLL more than 15 weeks. Delayed reversible and rather pronounced myelosuppression was the major side-effect observed in median 6 weeks from the start of Prednimustine with a median duration of 4 weeks.

Electrolytes and whole body potassium in acute leukemia

In a consecutive series of 22 patients with acute leukemia, the total body potassium was studied in 18 patients on 39 occasions during relapse and remission. Total body water was also determined. A control group consisting of 88 age-matched healthy volunteers was also studied. The patients had a significantly lower mean potassium concentration, per kg body weight, per kg lean body mass and per kg water, than the controls (p less than 0.001). Individually, 11 out of the 18 patients had at least one value below the lower 95% confidence limit. Hypokalemia was frequent both in the patients with low (7/11) and normal (3/6) potassium per kg lean body mass. Five of 13 investigated patients showed laboratory indications of secondary hyperaldosteronism, which might be partly responsible for the hypokalemia. Increased serum or urine levels of lysozyme were found in 62% of the patients.