Asparaginase combined with discontinuous dexamethasone improves antileukemic efficacy without increasing osteonecrosis in preclinical models

Asparaginase: How to Better Manage Toxicities in Adults

PURPOSE OF REVIEW

This review aims to help oncologists who predominantly treat adults better understand and manage asparaginase associated toxicities and prevent unnecessary discontinuation or reluctance of its use.

RECENT FINDINGS

Given the data supporting the benefit of incorporating multiple doses of asparaginase in pediatric type regimens, it is prudent to promote deeper understanding of this drug, particularly its toxicities, and its use so as to optimize treatment of ALL. Although asparaginase is associated with a variety of toxicities, the vast majority are not life threatening and do not preclude repeat dosing of this important drug. Understanding the pharmacology and toxicity profile of asparaginase is critical to dosing asparaginase appropriately in order to minimize these toxicities.

[Osteonecrosis-severe side effect of treatment for acute lymphoblastic leukemia]

Osteonecrosis occurs as an acute and long-term serious side effect in children, adolescents, and adults with acute lymphoblastic leukemia. It is associated with severe pain and reduced mobility, ultimately leading to joint destruction and significant long-term morbidity. The cumulative incidence ranges from 11 to 20% in adolescents and young adults. In symptomatic patients, multiple joints are frequently affected, which in turns poses a risk factor for the development of severe osteonecrosis. The genesis of leukemia-associated osteonecrosis is multifactorial. Risk factors include the use of corticosteroids and asparaginase. These exert their effects on the blood supply to the bone through hypercholesterolemia, hypertriglyceridemia, and hypertension. Bacteriemia, genetic susceptibility, and stem cell transplantation pose additional risk factors. The treatment of osteonecrosis is challenging and not evidence based. Preventive measurements have as yet mainly been tested in preclinical models.

Orthopaedic adverse events among adolescents and adults treated with asparaginase for acute lymphoblastic leukaemia

Osteonecrosis (ON) is a complication of acute lymphoblastic leukaemia (ALL) treatment with patient- (age, female sex, genetic polymorphisms, presence of metabolic syndrome) and treatment-specific (glucocorticoid type and schedule) risk factors described. The potential role of asparaginase in increasing risk of ON via effects on coagulation, lipid metabolism, and steroid clearance is now also recognised. Paediatric studies consistently identify age as a key risk factor for ON, with adolescents at higher risk than young children. Fewer studies comprehensively report on risk of ON in adults, but available evidence suggests that adolescents and young adults (AYAs) treated with corticosteroid and asparaginase-containing paediatric-inspired regimens are more at risk than older adults treated with paediatric-inspired or traditional adult regimens. There are few proven strategies to prevent or mitigate the severity of ON and other orthopaedic complications of ALL therapy. Future clinical trials should carefully ascertain orthopaedic adverse events in adults. Evidence-based guidelines should be developed for management of orthopaedic adverse events in adults being treated for ALL, especially high-risk AYAs being treated with paediatric-inspired regimens.

Effects of zoledronic acid on osteonecrosis and acute lymphoblastic leukemia treatment efficacy in preclinical models

BACKGROUND

Osteonecrosis is a devastating side effect of acute lymphoblastic leukemia (ALL) therapy. Associations between bone density loss and osteonecrosis have sparked interest in using bisphosphonates to reduce this complication.

PROCEDURE

We assessed the impact of zoledronic acid (ZA) on the development of osteonecrosis in murine models when used either throughout therapy (continuous administration) or late in therapy after vascular lesions have developed but before osteonecrosis has occurred. Effects on bone density were measured using microcomputed tomography (μCT)-assessed tibial cortical thickness, while osteonecrosis was assessed histologically in the distal femur. Effects on antileukemic efficacy of chemotherapy were evaluated in both immunocompetent/syngeneic and patient-derived xenograft (PDX) models.

RESULTS

Continuous administration of ZA with chemotherapy prevented chemotherapy-associated bone loss (p < .001) and reduced osteonecrosis (p = .048). Late initiation of ZA diminished bone loss (p < .001) but had no impact on the development of osteonecrosis (p = .93). In the immunocompetent murine ALL model, mice treated with ZA and chemotherapy succumbed to leukemia sooner than mice treated with chemotherapy alone (p = .046). Analysis using PDX showed a nonsignificant decrease in survival with ZA (p = .17).

CONCLUSION

Our data indicate ZA may prevent osteonecrosis if begun with chemotherapy but showed no benefit when administered later in therapy. However, ZA may also reduce the antileukemic efficacy of chemotherapy.

Osteonecrosis in Adults With Acute Lymphoblastic Leukemia: An Unmet Clinical Need

Osteonecrosis is a serious complication of antileukemic therapy associated with severe pain and reduced mobility, ultimately leading to joint destruction and significant long-term morbidity. The 5-year cumulative incidence of osteonecrosis ranges from 11% to 20% in adolescents and young adults to 3% to 8% in patients aged 30 years and older. Most symptomatic patients have multiple joints affected, which in turn poses a risk factor for developing severe osteonecrosis. Osteonecrosis has a multifactorial genesis. Treatment-associated risk factors for developing osteonecrosis depend on the therapeutic context including the use of glucocorticosteroids and the simultaneous and/or intensified use of asparaginase (ASP) which may, among others, exert its effect on blood supply to the bone through hypertriglyceridemia, hypercholesterolemia, and hypertension. Allogeneic hematopoietic stem cell transplantation, bloodstream infections, and genetic factors may additionally impact the risk of osteonecrosis. In this article, the authors used the best available evidence in the literature to develop management recommendations for the use in the context of steroid and asparaginase containing regimens. These considerations may be helpful for similar treatment approaches.

The Metabolic Remodelling in Lung Cancer and Its Putative Consequence in Therapy Response

Lung cancer is the leading cause of cancer-related deaths worldwide in both men and women. Conventional chemotherapy has failed to provide long-term benefits for many patients and in the past decade, important advances were made to understand the underlying molecular/genetic mechanisms of lung cancer, allowing the unfolding of several other pathological entities. Considering these molecular subtypes, and the appearance of promising targeted therapies, an effective personalized control of the disease has emerged, nonetheless benefiting a small proportion of patients. Although immunotherapy has also appeared as a new hope, it is still not accessible to the majority of patients with lung cancer.The metabolism of energy and biomass is the basis of cellular survival. This is true for normal cells under physiological conditions and it is also true for pathophysiologically altered cells, such as cancer cells. Thus, knowledge of the metabolic remodelling that occurs in cancer cells in the sense of, on one hand, surviving in the microenvironment of the organ in which the tumour develops and, on the other hand, escaping from drugs conditioned microenvironment, is essential to understand the disease and to develop new therapeutic approaches.