Recurrent cardiotoxicity potentiated by the interaction of proteasome inhibitor and immunomodulatory therapy for the treatment of multiple myeloma

Patients with multiple myeloma (MM) have improved treatment options, including immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs). Despite their efficacy, increased rates of cardiovascular (CV) complications occur in patients exposed to some of these therapies. While previous research has focused on identifying the toxicities inherent to each specific agent, the CV side effects may be potentiated by the combination of PIs and IMiDs plus dexamethasone. We present a patient with MM with recurrent cardiotoxicity only when exposed to combination PI and IMiD-based therapy. We also review the literature in this context, and propose a potential algorithm for cardiotoxicity prevention in this population.

Multiple Myeloma, Version 3.2017, NCCN Clinical Practice Guidelines in Oncology

Multiple myeloma (MM) is caused by the neoplastic proliferation of plasma cells. These neoplastic plasma cells proliferate and produce monoclonal immunoglobulin in the bone marrow causing skeletal damage, a hallmark of multiple myeloma. Other MM-related complications include hypercalcemia, renal insufficiency, anemia, and infections. The NCCN Multiple Myeloma Panel members have developed guidelines for the management of patients with various plasma cell dyscrasias, including solitary plasmacytoma, smoldering myeloma, multiple myeloma, systemic light chain amyloidosis, and Waldenström's macroglobulinemia. The recommendations specific to the diagnosis and treatment of patients with newly diagnosed MM are discussed in this article.

Farnesyltransferase Inhibitors and Their Role in the Treatment of Multiple Myeloma

BACKGROUND

Ras mutations are among the most common oncogene mutations found in multiple myeloma (MM). Patients with mutated Ras are less likely to respond to chemotherapy and have a shortened median survival. Therefore, targeting Ras farnesylation may be a valuable approach to treatment of MM. R115777 (tipifarnib) is a potent farnesyltransferase inhibitor (FTI) presently undergoing phase II/III clinical trials.

METHODS

We reviewed the preclinical and clinical experience of FTIs as antineoplastic agents and describe their potential role in the treatment of MM.

RESULTS

FTIs are a novel group of agents that selectively inhibit farnesyltransferase, an enzyme responsible for the posttranslational modification of several proteins including Ras. Since Ras is among the most commonly mutated oncogenes associated with cancer, this class of drugs has been evaluated in clinical trials in a diversity of tumors. R115777 has been evaluated in a phase II clinical trial in patients with advanced myeloma and found to be well tolerated. It induced disease stabilization in more than 60% of patients with advanced myeloma.

CONCLUSIONS

The drug selectively targets farnesyltransferase, but this effect did not correlate with disease stabilization, suggesting that these drugs may be targeting a survival pathway independent of Ras processing. Further studies will evaluate the use of FTI in maintenance therapy as well as in combination with other agents in advanced myeloma.

HDAC11 as a candidate therapeutic target in multiple myeloma

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Background: Histone deacetylase (HDAC) inhibitors (HDI) have a therapeutic niche in multiple myeloma (MM) due to their ability to salvage proteasome inhibitor and immunomodulatory drug responsiveness in refractory patients, thus raising interest in this therapeutic class. Selective HDI may further improve therapeutic efficacy. Methods: B cell lymphopoiesis was evaluated using Tg-HDAC11-eGFP mice expressing eGFP regulated by the HDAC11 promoter and congenic mouse strains deficient in HDAC11 expression globally (B6.HDAC11-/-) or targeted to the B cell lineage (CD19Cre.HDAC11-/-). Molecular and pharmacologic means were used to impair HDAC11 in established MM cell lines. Viability was measured by activated caspase-3, Annexin/PI (A/PI) staining, and CCK-8 viability assay. Subcellular localization changes induced by HDI and identification of the novel binding partner IRF4 were assessed by proximity ligation assay (PLA). Results: Profound eGFP increases in PC of Tg-HDAC11-eGFP mice suggest HDAC11 influences late stage B cell development. In addition, HDAC11 deficiency results in dramatically reduced PC in the bone marrow and periphery. PC depletion in CD19Cre.HDAC11-/-mice suggests activity inherent in B cells rather than via externally derived signals. Quisinostat (QS), an HDI with enhanced HDAC11 selectivity, showed dose-dependent cytotoxicity in 10 MM cell lines (EC50 1-10nM). This activity was synergistic with bortezomib (BTZ) and carfilzomib (CFZ) in RPMI-8226 cells, while synergism was amplified in the BTZ-resistant RPMI-8226-B25 cell line. Exposure of RPMI-8226 cells to QS decreased detection of nuclear, but not cytosolic, HDAC11. Targeted siRNA–mediated silencing of HDAC11 in RPMI-8226 cells activated caspase-3 and reduced viability by A/PI staining. PLA of MM cell lines showed a novel interaction between HDAC11 and IRF4, an essential regulator of PC differentiation and MM survival, unmasking a potential mechanism for HDAC11-induced cytotoxicity in MM. This interaction was disrupted by QS. Conclusions: We show that HDAC11 inhibition reduces MM cell survival in vitro. Furthermore, we identify IRF4 as a binding partner for HDAC11 and propose this interaction as a candidate mechanism regulating PC maturation and MM survival.

IL-2 promotes early Treg reconstitution after allogeneic hematopoietic cell transplantation

Graft-versus-host disease (GvHD) remains a major cause of transplant-related mortality. Interleukin-2 (IL-2) plus sirolimus (SIR) synergistically reduces acute GvHD in rodents and promotes regulatory T cells. This phase II trial tested the hypothesis that IL-2 would facilitate STAT5 phosphorylation in donor T cells, expand regulatory T cells, and ameliorate GvHD. Between 16th April 2014 and 19th December 2015, 20 patients received IL-2 (200,000 IU/m2 thrice weekly, days 0 to +90) with SIR (5-14 ng/mL) and tacrolimus (TAC) (3-7 ng/mL) after HLA-matched related or unrelated allogeneic hematopoietic cell transplantation (HCT). The study was designed to capture an increase in regulatory T cells from 16.0% to more than 23.2% at day +30. IL-2/SIR/TAC significantly increased regulatory T cells at day +30 compared to our published data with SIR/TAC (23.8% vs. 16.0%, P=0.0016; 0.052 k/uL vs. 0.037 k/uL, P=0.0163), achieving the primary study end point. However, adding IL-2 to SIR/TAC led to a fall in regulatory T cells by day +90 and did not reduce acute or chronic GvHD. Patients who discontinued IL-2 before day +100 showed a suggested trend toward less grade II-IV acute GvHD (16.7% vs. 50%, P=0.1475). We surmise that the reported accumulation of IL-2 receptors in circulation over time may neutralize IL-2, lead to progressive loss of regulatory T cells, and offset its clinical efficacy. The amount of phospho-STAT3+ CD4+ T cells correlated with donor T-cell activation and acute GvHD incidence despite early T-cell STAT5 phosphorylation by IL-2. Optimizing IL-2 dosing and overcoming cytokine sequestration by soluble IL-2 receptor may sustain lasting regulatory T cells after transplantation. However, an approach to target STAT3 is needed to enhance GvHD prevention. (clinicaltrials.gov identifier: 01927120).

Clonal haemopoiesis and therapy-related myeloid malignancies in elderly patients: a proof-of-concept, case-control study

BACKGROUND

Clonal haemopoiesis of indeterminate potential (CHIP) is an age-associated genetic event linked to increased risk of primary haematological malignancies and increased all-cause mortality, but the prevalence of CHIP in patients who develop therapy-related myeloid neoplasms is unknown. We did this study to investigate whether chemotherapy-treated patients with cancer who have CHIP are at increased risk of developing therapy-related myeloid neoplasms.

METHODS

We did a nested, case-control, proof-of-concept study to compare the prevalence of CHIP between patients with cancer who later developed therapy-related myeloid neoplasms (cases) and patients who did not develop these neoplasms (controls). We identified cases from our internal biorepository of 123 357 patients who consented to participate in the Total Cancer Care biobanking protocol at Moffitt Cancer Center (Tampa, FL, USA) between Jan 1, 2006, and June 1, 2016. We included all individuals who were diagnosed with a primary malignancy, were treated with chemotherapy, subsequently developed a therapy-related myeloid neoplasm, and were 70 years or older at either diagnosis. For inclusion in this study, individuals must have had a peripheral blood or mononuclear cell sample collected before the diagnosis of therapy-related myeloid neoplasm. Controls were individuals who were diagnosed with a primary malignancy at age 70 years or older and were treated with chemotherapy but did not develop therapy-related myeloid neoplasms. Controls were matched to cases in at least a 4:1 ratio on the basis of sex, primary tumour type, age at diagnosis, smoking status, chemotherapy drug class, and duration of follow-up. We used sequential targeted and whole-exome sequencing and described clonal evolution in cases for whom paired CHIP and therapy-related myeloid neoplasm samples were available. The primary endpoint of this study was the development of therapy-related myeloid neoplasm and the primary exposure was CHIP.

FINDINGS

We identified 13 cases and 56 case-matched controls. The prevalence of CHIP in all patients (23 [33%] of 69 patients) was higher than has previously been reported in elderly individuals without cancer (about 10%). Cases had a significantly higher prevalence of CHIP than did matched controls (eight [62%] of 13 cases vs 15 [27%] of 56 controls, p=0·024; odds ratio 5·75, 95% CI 1·52-25·09, p=0·013). The most commonly mutated genes in cases with CHIP were TET2 (three [38%] of eight patients) and TP53(three [38%] of eight patients), whereas controls most often had TET2 mutations (six [40%] of 15 patients). In most (four [67%] of six patients) cases for whom paired CHIP and therapy-related myeloid neoplasm samples were available, the mean allele frequency of CHIP mutations had expanded by the time of the therapy-related myeloid neoplasm diagnosis. However, a subset of paired samples (two [33%] of six patients) had CHIP mutations that decreased in allele frequency, giving way to expansion of a distinct mutant clone.

INTERPRETATION

Patients with cancer who have CHIP are at increased risk of developing therapy-related myeloid neoplasms. The distribution of CHIP-related gene mutations differs between individuals with therapy-related myeloid neoplasm and those without, suggesting that mutation-specific differences might exist in therapy-related myeloid neoplasm risk.

FUNDING

Moffitt Cancer Center.

Management of Biologic Therapy in Moderate to Severe Psoriasis in Surgical Patients: Data From the Spanish Biobadaderm Registry

BACKGROUND AND OBJECTIVE

We now have considerable experience in the use of biologic agents to treat psoriasis, but doubts about management arise in certain clinical settings. Surgery is one of them. Although treatment guidelines advise that biologics be suspended before major surgery, data about actual clinical practices and associated complications are lacking. We aimed to analyze current practice in the clinical management of these cases.

METHODS

Retrospective study of cases in the Biobadaderm database. We analyzed the management of biologic therapy in patients with psoriasis who underwent surgical procedures.

RESULTS

Forty-eight of the 2113 patients registered in Biobadaderm underwent surgery. The largest percentage of procedures (31%) involved skin lesions. Biologic treatment was interrupted in 42% of the cases. No postsurgical complications were significantly related to treatment interruption. Likewise we detected no associations between treatment interruption and other variables, such as sex, age, or duration or severity of psoriasis.

CONCLUSION

Continuity of biologic treatment and the risk of postsurgical complications were not associated in this study, although conclusions are limited by the small sample size.

Development of multiorganic calciphylaxis during teriparatide, vitamin D, and calcium treatment

Non-uremic calciphylaxis is a severe rare disorder characterized by ischemic necrosis. Recently, three cases of cutaneous calciphylaxis have been described in the context of teriparatide treatment. We present a 51-year-old woman with alcoholic cirrhosis who developed multiorganic calciphylaxis shortly after starting teriparatide treatment associated with calcium and 25-hydroxyvitamin D supplements for severe osteoporosis. After lengthy care of the infectious complications and treatment with bisphosphonates and sodium thiosulfate progressive improvement was observed over a 3-year period. The time between the initiation of teriparatide and the development of calciphylaxis suggests that this agent may have been the triggering factor of this process. Nevertheless, other non-negligible risk factors for calciphylaxis such as alcoholic liver disease, obesity, and vitamin D treatment must also be considered in this patient. Considering the severity of this extremely rare clinical condition, better knowledge of the risk factors related to calciphylaxis development is mandatory.