Development and characterization of three cell culture systems to investigate the relationship between primary bone marrow adipocytes and myeloma cells

ECM-mimicking hydrogel models of human adipose tissue identify deregulated lipid metabolism in the prostate cancer-adipocyte crosstalk under antiandrogen therapy

Antiandrogen therapies are effectively used to treat advanced prostate cancer, but eventually cancer adaptation drives unresolved metastatic castration-resistant prostate cancer (mCRPC). Adipose tissue influences metabolic reprogramming in cancer and was proposed as a contributor to therapy resistance. Using extracellular matrix (ECM)-mimicking hydrogel coculture models of human adipocytes and prostate cancer cells, we show that adipocytes from subcutaneous or bone marrow fat have dissimilar responses under the antiandrogen Enzalutamide. We demonstrate that androgen receptor (AR)-dependent cancer cells (LNCaP) are more influenced by human adipocytes than AR-independent cells (C4-2B), with altered lipid metabolism and adipokine secretion. This response changes under Enzalutamide, with increased AR expression and adipogenic and lipogenic genes in cancer cells and decreased lipid content and gene dysregulation associated with insulin resistance in adipocytes. This is in line with the metabolic syndrome that men with mCRPC under Enzalutamide experience. The all-human, all-3D, models presented here provide a significant advance to dissect the role of fat in therapy response for mCRPC.

Inhibition of acyl-CoA synthetase long-chain isozymes decreases multiple myeloma cell proliferation and causes mitochondrial dysfunction

Multiple myeloma (MM) is an incurable cancer of plasma cells with a 5-year survival rate of 59%. Dysregulation of fatty acid (FA) metabolism is associated with MM development and progression; however, the underlying mechanisms remain unclear. Herein, we explore the roles of long-chain fatty acid coenzyme A ligase (ACSL) family members in MM. ACSLs convert free long-chain fatty acids into fatty acyl-CoA esters and play key roles in catabolic and anabolic fatty acid metabolism. Analysis of the Multiple Myeloma Research Foundation (MMRF) CoMMpassSM study showed that high ACSL1 and ACSL4 expression in myeloma cells are both associated with worse clinical outcomes for MM patients. Cancer Dependency Map (DepMap) data showed that all five ACSLs have negative Chronos scores, and ACSL3 and ACSL4 were among the top 25% Hallmark Fatty Acid Metabolism genes that support myeloma cell line fitness. Inhibition of ACSLs in myeloma cell lines in vitro, using the pharmacological inhibitor Triacsin C (TriC), increased apoptosis, decreased proliferation, and decreased cell viability, in a dose- and time-dependent manner. RNA-sequencing analysis of MM.1S cells treated with TriC showed a significant enrichment in apoptosis, ferroptosis, and endoplasmic reticulum (ER) stress, and proteomic analysis of these cells revealed enriched pathways for mitochondrial dysfunction and oxidative phosphorylation. TriC also rewired mitochondrial metabolism by decreasing mitochondrial membrane potential, increasing mitochondrial superoxide levels, decreasing mitochondrial ATP production rates, and impairing cellular respiration. Overall, our data support the hypothesis that suppression of ACSLs in myeloma cells is a novel metabolic target in MM that inhibits their viability, implicating this family as a promising therapeutic target in treating myeloma.

Effect of adipose tissue on the development of multiple myeloma

Multiple myeloma (MM), also referred to as Kahler's disease, is a cancer characterized by the uncontrolled growth of abnormal plasma cells and is associated with alterations in the bone tissue microenvironment. Bone marrow adipose tissue (BMAT), which comprises approximately ten percent of total body fat, can influence the progression, survival, and drug resistance of MM cells through paracrine, hormonal, and metabolic pathways. Obesity can lead to an increase in BMAT mass, which not only disrupts bone metabolism but also reduces bone density, potentially progressing from monoclonal gammopathy of undetermined significance, a benign condition, to MM. A range of factors, including impaired fatty acid metabolism, increased production of adipokines that support myeloma, and heightened expression of oncogenic microRNAs in multiple myeloma, contribute to the progression of this incurable blood cancer. To better understand the relationship between excess adipose tissue accumulation and the risk of developing multiple myeloma, a comprehensive review of published data was conducted.

Correlation Between Bariatric Surgery and the Risk of Multiple Myeloma: Results from an Evidence-Based Strategy

OBJECTIVE

We conducted a meta-analysis of current literature to assess whether bariatric surgery(BS) has a positive effect on reducing the risk of multiple myeloma(MM).

METHODS

Relevant studies meeting the criteria were systematically reviewed using databases such as PubMed, Web of Science, Embase (Ovid platform), MEDLINE, and the Cochrane Library. The meta-analysis utilized hazard ratios (RR) and 95% confidence intervals (CI) to analyze the correlation between BS and the risk of MM. STATA software (version 12.0) was employed for the meta analysis.

RESULTS

The meta-analysis included 10 eligible studies, involving 2,452,503 patients with obesity. The results demonstrated a significant reduction in the risk of multiple myeloma in patients with obesity after bariatric surgery compared to non-surgical patients with obesity (RR = 0.51, 95%CI: 0.31-0.84). Subgroup analyses revealed a decreased probability of developing multiple myeloma in European patients with obesity and North American patients with obesity who underwent bariatric surgery. Studies with a sample size greater than or equal to 100,000 indicated a significantly reduced risk of multiple myeloma in patients with obesity undergoing bariatric surgery compared to the non-surgical group (RR: 0.45, 95%CI: 0.23-0.88, P < 0.02). Two publications before 2010 showed no significant difference in the incidence of multiple myeloma between the surgical and non-surgical groups (RR: 0.61, 95% CI: 0.14-2.63, P = 0.504), while publications after 2010 demonstrated a reduced incidence in the surgical group (RR: 0.51, 95% CI: 0.30-0.86, P = 0.012).

CONCLUSION

Our meta-analysis results suggest a reduced risk of multiple myeloma in patients with obesity following bariatric surgery.

PROSPERO REGISTRATION

CRD42023485668.

Bone marrow adipocyte: Origin, biology and relationship with hematological malignancy

Bone marrow adipose tissue (BMAT) has been histologically recognized for decades. In this study, we performed a bibliometric analysis to quantitatively analyze the clusters of keywords of BMAT and hematopoiesis to better understand BMAT and hematopoiesis. Starting with conclusive keywords, our results demonstrated that BMAds is distinct from extramedullary adipose tissues and maintains a routine but dynamic accumulation throughout an individual's life. Various pathophysiological factors take part in dysregulation of the adipose-osteogenic balance throughout life. Bone marrow adipocytes (BMAds) are also contradictorily involved in normal hematopoiesis, and positively participate in the occurrence and progression of hematologic malignancies, exerting a chemoprotective role in tumor treatment. Mechanically, metabolic reprogramming and abnormal secretory profile of BMAds and tumor cells play a critical role in the chemotherapy resistance. Overall, we hope that this work will provide new ideas for relevant future research on BMAds.

Obesity and myeloma: Clinical and mechanistic contributions to disease progression

Obesity and obesogenic behaviors are positively associated with both monoclonal gammopathy of unknown significance (MGUS) and multiple myeloma (MM). As the only known modifiable risk factor, this association has emerged as a new potential target for MM prevention, but little is known about the mechanistic relationship of body weight with MM progression. Here we summarize epidemiological correlations between weight, body composition, and the various stages of myeloma disease progression and treatments, as well as the current understanding of the molecular contributions of obesity-induced changes in myeloma cell phenotype and signaling. Finally, we outline groundwork for the future characterization of the relationship between body weight patterns, the bone marrow microenvironment, and MM pathogenesis in animal models, which have the potential to impact our understanding of disease pathogenesis and inform MM prevention messages.