Dietary and microbiome evidence in multiple myeloma and other plasma cell disorders

Disparities in relapsed or refractory multiple myeloma: recommendations from an interprofessional consensus panel

Many studies have documented racial, socioeconomic, geographic, and other disparities for United States (US) patients with multiple myeloma pertaining to diagnosis and frontline management. In contrast, very little is known about disparities in the management of relapsed/refractory multiple myeloma (RRMM) despite a plethora of novel treatment options. In this review, we discuss the manifestations of disparities in RRMM and strategies to mitigate their impact. Immunomodulatory drugs can create disparities on many axes, for example inappropriately low dosing due to Duffy-null status as well as time toxicity and financial toxicity from logistical hurdles for socioeconomically vulnerable patients. Access to myeloma expertise at high-volume centers is a critical consideration given the disconnect between how drugs like carfilzomib and dexamethasone are prescribed in trials versus optimized in real-world practice to lower toxicities. Disparities in chimeric antigen receptor T-cell therapy and bispecific antibody therapy span across racial, ethnic, and socioeconomic lines in large part due to their limited availability outside of high-volume centers. Another insidious source of disparities is supportive care in RRMM, ranging from inadequate pain control in Black patients to limited primary care provider access in rural settings. We discuss the rationales and evidence base for several solutions aimed at mitigating these disparities: for example, (1) bidirectional co-management with community-based oncologists, (2) screening for risk factors based on social determinants of health, (3) strategies to build patient trust with regard to clinical trials, and (4) longitudinal access to a primary care provider. As the treatment landscape for RRMM continues to expand, these types of efforts by the field will help ensure that this landscape is equally accessible and traversable for all US patients.

Functional cure and long-term survival in multiple myeloma: how to challenge the previously impossible

Multiple myeloma (MM) is a heterogeneous disease with survival ranging from months to decades. The goal of 'cure' remains elusive for most patients, but has been shown to be possible, with durable remission and a transition to a plateau phase (analogous to monoclonal gammopathy of uncertain significance/smoldering myeloma). In this review, two representative cases set the stage to illustrate how this might be possible and what still needs to be determined to achieve functional disease control over a prolonged period. Several developments have emerged, such as improved diagnostics including the definitions and use of SLiM-CRAB criteria and measurable residual disease (MRD) with whole-genome/single-cell sequencing as well as other correlates to better understand disease biology. These advances enable earlier detection, more accurate risk stratification and improved personalized treatment strategies by facilitating analysis of genetic alterations and clonal heterogeneity. Whole-genome sequencing may also identify driver mutations and modes of resistance to immunotherapies as well as other targeted therapies. Today, induction with a CD38 antibody, proteasome inhibitor, immunomodulatory drug, and dexamethasone, potentially followed by autologous stem cell transplantation and lenalidomide maintenance, can be considered standard of care for transplant-eligible (TE) patients with newly diagnosed MM (NDMM). That prolonged disease control and functional cure can be achieved in non-transplant-eligible (NTE) patients is currently emerging as a distinct possibility: data from phase III trials that incorporate a CD38 antibody into the treatment of NTE NDMM patients demonstrate impressive MRD negativity rates that appear sustained over several years. While the long-term durability of chimeric antigen receptor T cells, bi-specific antibodies and other immunotherapies are being evaluated, several clinical trials are now investigating their role in frontline treatment for TE and NTE patients. These trials will address whether chimeric antigen receptor T-cell therapy will replace autologous stem cell transplantation and whether such immunotherapies will represent a truly curative option. We conclude that while cure remains elusive, the concept of operational or functional cure provides a new benchmark to strive for and is an emerging area of active and potentially achievable clinical research for MM.

Causal associations between the gut microbiota and multiple myeloma: a two-sample Mendelian randomization study

Background

Previous observational studies have indicated a potential association between the gut microbiota and multiple myeloma (MM). However, the relationship between the gut microbiota and MM remains unclear. This study aimed to ascertain the existence of a causal link between the gut microbiota and MM.

Methods

To investigate the potential causal relationship between gut microbiota and MM, a two-sample Mendelian randomization (MR) analysis was conducted. Exposure data was obtained from the MiBioGen consortium, which provided genetic variants associated with 211 bacterial traits. MM outcome data was obtained from the FinnGen consortium. The selection of Single nucleotide polymorphisms estimates was performed through meta-analysis using inverse-variance weighting, and sensitivity analyses were conducted using weighted median, MR Egger, Simple mode, and MR-PRESSO.

Results

The results of the study demonstrated a significant positive correlation between the genus Eubacterium ruminantium group and the risk of MM (OR 1.71, 95% CI 1.21 to 2.39). Conversely, the genus: Dorea (OR 0.46, 95% CI 0.24 to 0.86), Coprococcus1 (OR 0.47, 95% CI 0.22 to 1.00), RuminococcaceaeUCG014 (OR 0.57, 95% CI 0.33 to 0.99), Eubacterium rectale group (OR 0.37, 95% CI 0.18 to 0.77), and order: Victivallales (OR 0.62, 95% CI 0.41-0.94), class: Lentisphaeria (OR 0.62, 95% CI 0.41 to 0.94), exhibited a negative association with MM. The inverse variance weighting analysis provided additional support for these findings.

Conclusion

This study represents an inaugural exploration of MR to investigate the connections between gut microbiota and MM, thereby suggesting potential significance for the prevention and treatment of MM.

Effects of immune cells in mediating the relationship between gut microbiota and myelodysplastic syndrome: a bidirectional two-sample, two-step Mendelian randomization study

BACKGROUND

The definitive establishment of a causal relationship between gut microbiota and myelodysplastic syndrome (MDS) has not been achieved. Furthermore, the involvement of immune cells in mediating the connection between gut microbiota and MDS is presently unclear.

METHODS

To elucidate the bidirectional correlation between gut microbiota and MDS, as well as to investigate the mediating role of immune cells, a bidirectional two-sample, two-step Mendelian randomization (MR) study was conducted. Summary statistics were obtained from genome-wide association studies (GWAS), including MDS (456,348 individuals), gut microbiota (18,340 individuals), and 731 immune cells signatures (3757 individuals).

RESULTS

Genetically predicted eight gut microbiota traits were significantly associated with MDS risk, but not vice versa. Through biological annotation of host-microbiome shared genes, we found that immune regulation may mediate the impact of gut microbiota on MDS. Subsequently, twenty-three immunophenotypes that exhibited significant associations with MDS risk and five of these immunophenotypes were under the causal influence of gut microbiota. Importantly, the causal effects of gut microbiota on MDS were significantly mediated by five immunophenotypes, including CD4 +T cell %leukocyte, CD127 on CD45RA - CD4 not regulatory T cell, CD45 on CD33 + HLA DR + WHR, CD33 on basophil, and Monocyte AC.

CONCLUSIONS

Gut microbiota was causally associated with MDS risk, and five specific immunophenotypes served as potential causal mediators of the effect of gut microbiota on MDS. Understanding the causality among gut microbiota, immune cells and MDS is critical in identifying potential targets for diagnosis and treatment.

Dietary risk factors for monoclonal gammopathy of undetermined significance in a racially diverse population

ABSTRACT

Monoclonal gammopathy of undetermined significance (MGUS), a precursor of multiple myeloma, is associated with shorter lifespan and cardiac, renal, neurologic, and immune-related comorbidities. There is little known about modifiable risk factors for this condition. To determine whether the risk of MGUS is associated with dietary factors in a racially diverse population, we conducted a US population-based case-control study from the National Health and Nutrition Examination Survey (1988-2004), which included 373 individuals with MGUS and 1406 matched controls. Diet was characterized by one 24-hour dietary recall, with gram intake of individual foods and beverages aggregated into groups. Unconditional multivariable logistic regressions were used to model associations between intake of several food groups and MGUS, with odds ratios (ORs) and 95% confidence intervals (CIs) reported for the highest relative to the lowest quantile of intake. Daily gram intake of several food and beverage groups were significantly associated with MGUS. MGUS was inversely associated with whole-grain bread, oats, and rice (OR, 0.70; 95% CI, 0.48-1.00; P < .05), fruits (excluding juice) and vegetables (OR, 0.69; 95% CI, 0.52-0.93; P = .02), vegetables (OR, 0.75; 95% CI, 0.56-0.99; P < .05), tomatoes (OR, 0.72; 95% CI, 0.51-1.00; P < .05), and cruciferous vegetables (OR, 0.44; 95% CI, 0.26-0.74; P < .01). Direct associations were observed for sugar-sweetened beverages (OR, 1.34; 95% CI, 1.00-1.78; P < .05), sugar-sweetened soft drinks (OR, 1.41; 95% CI, 1.01-1.96; P = .04), and artificially sweetened soft drinks (OR, 1.55; 95% CI, 1.04-2.33; P = .03). Our study shows that diet is potentially a modifiable risk factor for MGUS.

Conceptualizing an Integrative Multiple Myeloma Care: The Role of Nutrition, Supplements, and Complementary Modalities

Multiple Myeloma (MM) is the second most prevalent hematologic malignancy, and its incidence has been increasing enormously in recent years. The prognosis of MM has changed radically with the introduction of new drugs that have improved life expectancy; recurrences are a common occurrence during the course of the disease and are characterized by an increase in refractory to treatment. Moreover, MM patients are challenged by quality of life-related concerns while limited conventional therapy may be offered. This includes bone pain and dialysis due to the complications of acute renal failure. We, therefore, believe that it is very important to add new treatment modalities, including supplements, nutritional modifications, acupuncture, and mind-body therapies, with the goal of improving treatment tolerance, effectiveness, and patients' quality of life. Moreover, many patients use some of these supplements on their own, in the hope of reducing the side effects, so it is even more important to know their action and potential. The purpose of this review is to illustrate all these strategies potentially available to enrich our approach to this, to date, incurable disease.

Prevalence and impact of diabetes on survival of patients with multiple myeloma in different racial groups

ABSTRACT

Multiple myeloma (MM) is twice as common in Black individuals compared with in White individuals, and diabetes mellitus (DM) disproportionately affects Black patients. Although numerous studies have shown a correlation between DM and MM, this has not been studied in the context of race and in vivo mechanisms. We conducted a retrospective clinical study of 5383 patients with MM of which 15% had DM (White, 12% and Black, 25%). Multivariable Cox models showed reduced overall survival (OS) for patients with DM (hazard ratio, 1.27; 95% confidence interval, 1.11-1.47; P < .001). This appeared to be driven by a marked difference in OS between White patients with and without DM but not in Black patients. In contrast, obesity was associated with better OS in Black patients but not in White patients. To complement this analysis, we assessed MM growth in a genetically engineered immunocompromised nonobese diabetic (Rag1-/-/muscle creatinine kinase promoter expression of a human IGF1R [M] with a lysine [K] to arginine [R] point mutation) mouse model to evaluate the mechanisms linking DM and MM. MM.1S xenografts grew in more Rag1-/-/MKR mice and grew more rapidly in the Rag1-/-/MKR mice compared with in controls. Western blot analysis found that MM1.S xenografts from Rag1-/-/MKR mice had higher phosphorylated S6 ribosomal protein (Ser235/236) levels, indicating greater activation of the mammalian target of rapamycin pathway. Our study is, to our knowledge, the first to evaluate racial differences in DM prevalence and survival in MM, as well as the effect of DM on tumor growth in mouse models. Our results suggest that DM may contribute to the higher incidence of MM in Black patients; and to improve survival in MM, DM management cannot be ignored.

Regression of Intermediate-High Risk Monoclonal Gammopathy of Undetermined Significance (MGUS) With Long-term Use of Curcumin: A Case Report

Patients with intermediate-high risk MGUS are not offered therapeutic options to date and standard of care remains observation with re-evaluations of the patient every 3 to 6 months. Given the persistent risk of progression as well as potential complications experienced by some, and anxiety experienced by most patients, early intervention with non-toxic curcumin, aimed at potentially slowing down or stopping disease progression might be therapeutic. We present here an intermediate-high risk MGUS patient who has been taking curcumin for 16 years and has shown a decrease in disease markers and an increase in uninvolved immunoglobulins, adding to the body of evidence of benefit of curcumin to MGUS patients.

It is worth the weight: obesity and the transition from monoclonal gammopathy of undetermined significance to multiple myeloma

The overweight/obesity epidemic is a serious public health concern that affects >40% of adults globally and increases the risk of numerous chronic diseases, such as type 2 diabetes, heart disease, and various cancers. Multiple myeloma (MM) is a lymphohematopoietic cancer caused by the uncontrolled clonal expansion of plasma cells. Recent studies have shown that obesity is a risk factor not only for MM but also monoclonal gammopathy of undetermined significance (MGUS), a precursor disease state of MM. Furthermore, obesity may promote the transition from MGUS to MM. Thus, in this review, we summarize the epidemiological evidence regarding the role of obesity in MM and MGUS, discuss the biologic mechanisms that drive these disease processes, and detail the obesity-targeted pharmacologic and lifestyle interventions that may reduce the risk of progression from MGUS to MM.

Pre-Diagnosis Dietary Patterns and Risk of Multiple Myeloma in the NIH-AARP Diet and Health Study

Background

Despite patient interest in knowing whether diet is linked to multiple myeloma (MM), there is limited research on dietary patterns and MM risk. Two studies have assessed this risk, albeit with a small number of MM cases. The EPIC-Oxford cohort and Oxford Vegetarian study (65 MM cases) showed that fish eaters, vegetarians and vegans had significantly reduced MM risk compared to meat eaters. The Nurses' Health Study and Health Professionals Follow-up Study (478 MM cases) showed a significantly increased MM risk in men with Empirical Dietary Inflammatory Pattern.

Methods

The NIH-AARP Diet and Health study is a prospective cohort of 567,169 persons who completed a food frequency questionnaire in 1995-1996 and were followed until December 2011. Healthy Eating Index-2015 (HEI-2015), Healthy Diet Score (HDS), alternate Mediterranean Diet (aMED) and healthful Plant-based Diet Index (hPDI) scores were calculated using a priori defined methods and grouped into quartiles, with higher scores reflecting healthier eating patterns. We prospectively evaluated the association between pre-diagnosis dietary patterns and MM incidence in this cohort. Hazard ratios (HR) and 95% confidence intervals (95%CI) were estimated using multivariate Cox proportional hazards models adjusted for age at study entry, sex, race, body mass index, education, and total energy intake (by residual method). Sensitivity analysis was conducted to assess reverse causality by excluding MM cases diagnosed within one year of follow-up.

Results

Among 392,589 participants (after exclusions), a total of 1,366 MM cases (59% males; 92% non-Hispanic whites) were identified during the follow-up period. Analysis revealed a significant association between hPDI scores and reduced MM risk (highest vs lowest quartile, HR 0.85; 95%CI 0.73-1.0; p=0.043) (Table). In sensitivity analysis (1,302 MM cases), the association was no longer significant (HR 0.87; 95%CI 0.74-1.03; p 0.09) but trended in the same direction. This may be due to small sample size, given MM is a rare disease. HEI-2015, HDS and aMED scores were not associated with MM risk.

Conclusions

A healthful plant-based diet was associated with reduced MM risk in the NIH-AARP cohort. These results will help oncologists and patients make informed choices about their diet. To our knowledge, this is the largest epidemiologic study to date assessing pre-diagnosis dietary patterns and MM risk.