Diagnosed Multiple Myeloma Patients Research Articles

Optimizing Autologous Stem Cell Transplantation in Multiple Myeloma: The Impact of Intensive Chemomobilization

Most transplant-eligible multiple myeloma (MM) patients undergo autologous peripheral blood stem cell collection (PBSC) using G-CSF with on-demand plerixafor (G±P). Chemomobilization (CM) can be used as a salvage regimen after G±P failure or for debulking residual tumor burden ahead of autologous peripheral blood stem cell transplantation (ASCT). Prior studies utilizing cyclophosphamide-based CM have not shown long-term benefit. At our center, intensive CM (ICM) using a PACE- or HyperCVAD-based regimen has been used to mitigate "excessive" residual disease based on plasma cell burden or MM-related biomarkers. Given the lack of efficacy of non-intensive CM, we sought to determine the impact of ICM on event-free survival (EFS), defined as death, progressive disease, or unplanned treatment escalation. We performed a retrospective study of newly diagnosed MM patients who collected autologous PBSCs with the intent to proceed immediately to ASCT at our center between 7/2020 and 2/2023. Patients were excluded if they underwent a tandem autologous or sequential autologous-allogeneic transplant, had primary plasma cell leukemia, received non-ICM treatment (i.e., cyclophosphamide and/or etoposide), or had previously failed G±P mobilization. To appropriately evaluate the impact of ICM among those who potentially could have received it, we utilized a propensity score matching (PSM) approach whereby ICM patients were compared to a cohort of non-CM patients matched on pre-ASCT factors most strongly associated with the receipt of ICM. Of 451 patients identified, 61 (13.5%) received ICM (PACE-based, n=45; hyper-CVAD-based, n=16). Post-ICM/pre-ASCT, 11 patients (18%) required admission for neutropenic fever and/or infection. Among 51 evaluable patients, the overall response rate was 31%; however, 46 of 55 evaluable patients (84%) saw a reduction in M-spike and/or involved FLCs. Among those evaluated with longitudinal peripheral blood flow cytometry (n=8), 5 patients (63%) cleared circulating blood PCs post-ICM. Compared to patients mobilized with non-CM, ICM patients collected a slightly greater median number of CD34+ cells (10.8 vs 10.2 × 10⁶/kg, p=.018). The median follow-up was 30.6 months post-ASCT. In a PSM multivariable analysis, ICM was associated with significantly improved EFS (HR 0.30, 95% CI 0.14 to 0.67, p=.003), but not improved OS (HR 0.38, 95% CI 0.10 to 1.44, p=.2). ICM was associated with longer post-ASCT inpatient duration (+4.1 days, 95% CI, 2.4 to 5.8, p<.001), more febrile days (+0.96 days, 95% CI 0.50 to 1.4, p<.001), impaired platelet engraftment (HR 0.23, 95% CI 0.06 to 0.87, p=.031), more bacteremia (OR 3.41, 95% CI 1.20 to 9.31, p=.018), and increased antibiotic usage (cefepime: +2.3 doses, 95% CI 0.39 to 4.1, p=.018; vancomycin: +1.0 doses, 95% CI 0.23 to 1.8, p=.012). ICM was independently associated with improved EFS in a matched analysis involving MM patients with excessive disease burden at pre-ASCT workup. This benefit came at the cost of longer inpatient duration, more febrile days, greater incidence of bacteremia, and increased antibiotic usage in the immediate post-ASCT setting. Our findings suggest that ICM could be considered for a subset of MM patients, but its use must be weighed carefully against additional toxicity.

Research and Analysis of Molecules such as CD28, CD45RA, CD45RO, CD38, HLA-DR, and CD57 on T Cells in Multiple Myeloma.

For many years it has been postulated that the immune system controls the progress of multiple myeloma (MM). However, the phenotypes of T cells in MM remain to be elucidated. In this study, we compared the phenotypes of T cells, which were obtained from the peripheral blood, in MM patients with those in healthy donors (HD). The expression of CCR7, CD57, CD28, HLA-DR, CD38, CD45RA, and CD45RO were assessed on T cells from MM patients and HDs using multicolor flow cytometry (MFC). For this study, 17 newly diagnosed MM patients were selected, and 20 healthy people were selected as a control group. MFC was used to detect the markers on T cells. We detected significant increases in the expression levels of HLA-DR, CD38, and CD57on CD8+ T cells, significant decreases in the expression levels of CD28 and CD45RA on CD8+ T cells, and a decrease of CD4+ effec-tor T cells in MM patients, compared to the HD group. Our study shows that the accumulation of peripheral CD8+CD57+T cells, CD8+CD38high T cells, and CD8+HLA-DR+CD38high T cells is reflective of an ongoing antitumor T cell response and a progressive immune dysfunction in MM. During chemotherapy, the recovery of immune function can be monitored by detecting the proportion of activated molecules of T lymphocytes.

413 Evaluation of Osteoporosis in the Lumbar Spine in Multiple Myeloma Patients Using 18F-NaF PET/CT

INTRODUCTION: Multiple myeloma (MM) is a plasma cell malignancy that structurally damages and weakens the bone, most commonly in the spine, by inducing osteoporosis, osteolytic lesions and pathological fractures. Detecting molecular changes in bone metabolism, such as reduced osteoblastic activity and bone remodeling associated with MM, would allow for early diagnosis of osteoporosis in the lumbar spine and reduce risk for surgical spinal interventions. One such imaging candidate is 18F-NaF PET/CT, a molecular imaging technique sensitive to bone formation. METHODS: The FULIMA clinical trial (NCT02187731) was conducted with 70 newly diagnosed MM patients, with exclusion criteria leaving 33 patients for analysis (9 females, 24 males; mean age 66.6y). Patients’ trabecular body of the L1-L4 vertebrae was analyzed using 18F-NaF PET/CT scans to calculate and evaluate the linear associations among mean standardized NaF uptake value (SUVmean), mean Hounsfield unit (HU) values, and age. Receiver-operating characteristic (ROC) curve analysis with area under the curve (AUC) using the Wilson/Brown method assessed the predictive value of NaF uptake via SUVmean for osteoporosis determined by HU threshold. RESULTS: There was significant positive correlation between HU value and SUVmean (r = 0.64, p &lt; 0.0001) and negative correlations between age and both HU value (r = -0.59, p &lt; 0.0003) and SUVmean (r = -0.53, p = 0.002). Additionally, on average, there was a 29.1% difference in the NaF uptake of MM patients with osteoporosis (SUVmean = 7.0 ± 1.48) compared to normal MM patients (SUVmean = 4.96 ± 1.46). Predictive value of NaF per AUC analysis was 0.857 with p = 0.002. CONCLUSIONS: 18F-NaF PET/CT detects the decreased osteoblastic activity of osteoporosis in the lumbar spine with high precision and accuracy in MM patients, facilitating timely interventions and reducing risk for invasive procedures.

The Ratio of Serum Urea Nitrogen to Albumin Is a Better Predictor of Overall Survival in Multiple Myeloma Patients than Urea Nitrogen Alone

Introduction: Multiple myeloma (MM) is a malignant proliferative disease of plasma cells. Abnormally cloned plasma cells secrete large amounts of monoclonal immunoglobulins in the bone marrow of MM patients. Serum urea nitrogen (sUN) is a byproduct of protein metabolism, and its effect on MM patients’ prognoses remains unknown. Therefore, we analyzed MM patients’ clinical data to explore the role of sUN and sUN/serum albumin (sUAR) in the baseline tumor load and MM prognosis of MM patients. Methods: We downloaded the clinical data of 762 MM patients from the MMRF database. After excluding those without baseline sUN, 452 patients were finally included in the study. Smoothed curve fitting, threshold analysis, Tamhane’s T2 test, multivariate-adjusted Cox regression analysis, Kaplan-Meier (K-M) curves, and receiver operating characteristic (ROC) analysis were applied in the study. Results: There were 452 newly diagnosed MM patients included in this study. In most patient groups, sUN and sUAR were positively linked with β2-microglobulin (β2-MG) and lactic dehydrogenase (LDH) according to smoothing curve fitting and threshold analysis. The higher the ISS stage, the greater the values of sUN and sUAR. Furthermore, smoothed curve fitting and threshold analysis showed that sUN was correlated with overall survival (OS), although sUAR had a stronger correlation with OS and could be applied to a broader group. The results of a multivariate-adjusted Cox regression analysis demonstrated that sUN and sUAR were independent prognostic factors for OS. The K-M curve confirmed the correlation between higher sUN and sUAR levels and worse OS. β2-MG and LDH are generally recognized prognostic factors of OS. ROC analysis revealed that sUN might boost β2-MG and LDH’s predictive value and sUAR had a higher predictive value. Conclusion: This retrospective study based on the MMRF database showed that high sUN and sUAR levels were positively associated with β2-MG, LDH, and ISS staging, and sUAR exhibited a stronger correlation with OS than sUN alone.

DETERMINATION OF SERUM INTERLEUKIN-36 ALPHA, BETA, GAMMA AND INTERLEUKIN-17 LEVELS IN PATIENTS WITH MULTIPLE MYELOMA

Multiple myeloma (MM) is a hematologic malignancy characterized by bone marrow infiltration of clonal plasma cells. Today, there is no treatment for obtaining a complete cycle for MM. IL-36 is a cytokine composed of three agonists named alpha, beta, and gamma. Its increase in inflammation has been proven in the literature. It is also reported that IL-17 plays a role in some rheumatologic and malignant diseases together with inflammation. &#x0D; The aim of the study is to figure out the roles, if any, of IL-36 and IL-17 in the pathogenesis of multiple myeloma depending on their known physiology and to contribute to the literature to find new treatment options.&#x0D; 33 newly diagnosed MM patients who had never received any treatment and 33 healthy volunteers were included in the study. Basic laboratory parameters and interleukin levels in myeloma patient group and healthy group were included in the study.&#x0D; In the study, it was found that IL-36 alpha, beta, gamma, and IL-17 levels were statistically significantly lower in the disease group when compared to the healthy group. A negative correlation was found between IL-17 measurement and beta-2 microglobulin. Therefore, it was thought that IL-17 may be a marker to predict prognosis.&#x0D; In conclusion, we think that IL-36 and IL-17 may play a role in the etiopathogenesis of myeloma and IL-36 alpha and IL-17 may be associated with prognosis. However, there is a need for more comprehensive studies.

Autologous HSCT with novel agent-based induction and consolidation followed by lenalidomide maintenance for untreated multiple myeloma.

Triplet regimen comprising proteasome inhibitors, immunomodulatory drugs, and dexamethasone (DEX) is a recommended induction/consolidation therapy for multiple myeloma (MM) patients eligible for transplant. In this Japanese phase II study conducted from 2017 to 2019, newly diagnosed MM patients aged 20-65 received four induction cycles with bortezomib (Bor), lenalidomide (Len), and DEX (VRD), followed by Bor and high-dose melphalan with autologous stem cell rescue. Subsequently, they underwent four consolidation cycles with carfilzomib, Len, and DEX (KRD), followed by Len maintenance until disease progression. A total of 141 patients were analyzed. In an intent-to-treat population, the complete or better response post induction was 19.9%, rising to 39.7%, 58.9%, and 62.4% after transplant, consolidation, and 1-year maintenance, respectively. With a median follow-up of 38 months, the 3-year progression-free survival (PFS) rate was 83.5% and the 3-year overall survival rate was 92.5%. Severe adverse events (≥grade 3) occurred in ~30% of patients; however, there was no treatment-related mortality. These findings clearly showed the tolerability and effectiveness of this protocol. Nevertheless, patients with high-risk cytogenetics showed a trend toward lower 3-year PFS than those without (77.8% vs. 89.4%, p = 0.051), and ultra-high-risk cytogenetics (≥2 high-risk cytogenetics) had an even worse prognosis, with 61.2% 3-year PFS. To overcome this situation, a more potent treatment strategy incorporating novel agents such as the CD38-antibody should be assessed in future studies.

Detection of cytogenetic abnormalities in multiple myeloma by using optical genome mapping

Multiple myeloma (MM) is a plasma cell neoplasm characterized by numerous chromosomal number and structural abnormalities, which are of great significance for risk stratification and response evaluation of MM patients. Optical genome mapping (OGM) is a novel technology that has the potential to resolve many of the issues and limitations associated with traditional cytogenetic methods. To date, the clinical utility of OGM has been validated in the fields of cancer, reproduction, and embryonic dysplasia, et al. In this study, we compared OGM to traditional techniques for the first time in five newly diagnosed MM patients, and evaluated the potential of OGM for detecting cytogenetic aberrations and its clinical application value in MM.

The correlation between serum free light chain levels and plasma cell ratio in bone marrow biopsy in multiple myeloma

Aims: MM (Multiple myeloma) is the second most common hematological malignancy. In addition to the recent advances in treatment, new parameters are used in clinical practice in diagnosis and follow-up. sFLC (free chain kappa and lambda) shows the activation of the disease depending on the rate of MM malignant cell secretion in serum. However, the plasma cell (PC) ratio in bone marrow biopsy is still the gold standard in diagnosis. We examined the dynamic correlation between the PC ratio and the number of sFLC-related cells and the secretion rate. We aimed to examine whether a low PC ratio could be in a more aggressive form with a higher sFLC secretion with too much activity, thus examining the correlation between them.&#x0D; Methods: A total of 62 newly diagnosed MM patients admitted to Başkent University Faculty of Medicine İstanbul Hospital were included in the study. At the time of diagnosis, sFLC values were requested simultaneously with bone marrow biopsy. Radiological images were obtained with PET CT/MRI or CT.&#x0D; Results: In all MM groups, bone marrow PH percentages were not correlated with sFLC regardless of subtype. IgG kappa type MM had the highest sFLC values despite the lowest number of PHs, while Lambda light chain MM had the lowest sFLC despite the highest PH rates. &#x0D; Conclusion: These results showed us that sFLC rates are independent of the percentage of PC in MM. We believe that the two are not correlated and should be followed up together in the follow-up of the disease.

Expression of the chemokine receptor CCR1 decreases sensitivity to bortezomib in multiple myeloma cell lines

BackgroundThe proteasome inhibitor bortezomib is one of the primary therapies used for the haematological malignancy multiple myeloma (MM). However, intrinsic or acquired resistance to bortezomib, via mechanisms that are not fully elucidated, is a barrier to successful treatment in many patients. Our previous studies have shown that elevated expression of the chemokine receptor CCR1 in MM plasma cells in newly diagnosed MM patients is associated with poor prognosis. Here, we hypothesised that the poor prognosis conferred by CCR1 expression is, in part, due to a CCR1-mediated decrease in MM plasma cell sensitivity to bortezomib. MethodsIn order to investigate the role of CCR1 in MM cells, CCR1 was knocked out in human myeloma cell lines OPM2 and U266 using CRISPR-Cas9. Additionally, CCR1 was overexpressed in the mouse MM cell line 5TGM1. The effect of bortezomib on CCR1 knockout or CCR1-overexpressing cells was then assessed by WST-1 assay, with or without CCL3 siRNA knockdown or addition of recombinant human CCL3. NSG mice were inoculated intratibially with OPM2-CCR1KO cells and were treated with 0.7 mg/kg bortezomib or vehicle twice per week for 3 weeks and GFP+ tumour cells in the bone marrow were quantitated by flow cytometry. The effect of CCR1 overexpression or knockout on unfolded protein response pathways was assessed using qPCR for ATF4, HSPA5, XBP1, ERN1 and CHOP and Western blot for IRE1α and p-Jnk. ResultsUsing CCR1 overexpression or CRIPSR-Cas9-mediated CCR1 knockout in MM cell lines, we found that CCR1 expression significantly decreases sensitivity to bortezomib in vitro, independent of the CCR1 ligand CCL3. In addition, CCR1 knockout rendered the human MM cell line OPM2 more sensitive to bortezomib in an intratibial MM model in NSG mice in vivo. Moreover, CCR1 expression negatively regulated the expression of the unfolded protein response receptor IRE1 and downstream target gene XBP1, suggesting this pathway may be responsible for the decreased bortezomib sensitivity of CCR1-expressing cells. ConclusionsTaken together, these studies suggest that CCR1 expression may be associated with decreased response to bortezomib in MM cell lines.

Do Alarmins Have a Role in Multiple Myeloma?

Calprotectin (CLP), S100A6, and High Mobility Group Nucleosome-Binding Protein 1 (HMGN1), known as alarmins, are involved in the pathogenesis of many tumors. In this study, we aimed to inve stigate the relationship of serum CLP, S100A6, and HMGN1 levels with clinical and laboratory findings in Multiple Myeloma (MM) patients and their role in the pathogenesis of MM. We measured serum CLP, S100A6, and HMGN1 levels in 55 newly diagnosed patients and 32 healthy controls (HC). We determined significantly decreased serum CLP, S100A6 ve HMGN1 levels in MM patients compared to HC (p=0.012, p=0.001, p=0.030, respectively). ROC analysis was used to determine a diagnostic cut-off value for serum CLP, S100A6 and HMGN1; the cut off value for CLP was <98 ng/ml (AUC = 0.663, 95% CI 0.554-0.761, p=0.009), S100A6 was <1174.5 pg/ml (AUC = 0.706, 95% CI 0.598-0.799, p=0.001), and HMGN1 was <440.18 pg/ml (AUC = 0.640, 95% CI 0.530-0.740, p:0.03). CLP level was found to be statistically significantly in light chain MM patients ( 91.58±22.57) higher than in heavy chain MM patients (79.42±15.83) (p=0.03). A negative correlation was observed between CLP and M protein, IgG, globulin, and beta 2 microglobulin (correlation coefficient: -0,361; -0,370; -0,279; -0,300, p=0,024, p=006, p=0,04, p=0,0033). In this study, we found that serum CLP, S100A6, and HMGN1 levels were statistically lower in newly diagnosed MM patients compared to HC. These results suggest that CLP may binds to the paraprotein produced by heavy chain MM in the blood and therefore its blood levels are found to be low. Additionally, low levels of HMGN1, which is involved in DNA repair, suggest that HMGN1 may contribute to the complex genetic abnormalities found in MM.

Improved long-term survival rate in the responders to bortezomib, cyclophosphamide, dexamethasone induction therapy in a transplant-eligible cohort of predominantly middle-age multiple myeloma patients.

Multiple myeloma (MM) represents the second most common hematologic malignancy (15%). Induction with bortezomib, cyclophosphamide, and dexamthasone VCd (d: low dose dexamthasone) regimen is widely used due to its high effectiveness, low toxicity and good tolerability, particularly with renal impairment. Real-world data on the use of VCD in clinical practice is lacking. Evaluate the real-world experience of the VCD regimen. Retrospective. Tumor registry database of tertiary cancer care center. newly diagnosed MM patients who received VCD induction and underwent autologous stem cell transplant (ASCT) from July 2007 to July 2020. response evaluation, progression-free survival (PFS) and overall survival (OS). 87 patients. Of 102 patients who started induction with VCd, 87 patients experienced a partial response or more overall response rate of 85%). The median age of these 87 patients at diagnosis was 52 years, of which 29.9% presented with renal impairment and 60.3% of patients had stage 2 by the Revised International Staging System (R-ISS). Patients with a standard cytogenetic risk achieved a better response compared to those with a poor cytogenetic risk (P=.044). The post-induction response rates were 6.9% stringent complete remission (sCR), 35% complete remission (CR); 41.4% very good partial response (VGPR), and 16.1% partial response (PR), respectively; the response rates became greater for sCR and CR post-transplantation at day 100 with 16.1% sCR, 35.6% CR, 32.2% VGPR and 16.1% PR, respectively. The median PFS was 49 months and 5 years OS was 84%. PFS was better in patients who achieved sCR vs PR (83 vs 35 months, P=.037). High LDH, high-risk cytogenetic and stage 3 R-ISS showed a worse median PFS and OS. VCD induction in newly diagnosed MM is highly effective, convenient, tolerable and affordable regimen, especially in low and middle-income countries with limited resources, also with favorable outcomes and survival. while those who did not respond successfully shifted to VRD or VTD. The usual limitations of a retrospective analysis using registry-level data, no data on quality of life.

Multi-dimensional scaling techniques unveiled gain1q&loss13q co-occurrence in Multiple Myeloma patients with specific genomic, transcriptional and adverse clinical features

The complexity of Multiple Myeloma (MM) is driven by several genomic aberrations, interacting with disease-related and/or -unrelated factors and conditioning patients’ clinical outcome. Patient’s prognosis is hardly predictable, as commonly employed MM risk models do not precisely partition high- from low-risk patients, preventing the reliable recognition of early relapsing/refractory patients. By a dimensionality reduction approach, here we dissect the genomic landscape of a large cohort of newly diagnosed MM patients, modelling all the possible interactions between any MM chromosomal alterations. We highlight the presence of a distinguished cluster of patients in the low-dimensionality space, with unfavorable clinical behavior, whose biology was driven by the co-occurrence of chromosomes 1q CN gain and 13 CN loss. Presence or absence of these alterations define MM patients overexpressing either CCND2 or CCND1, fostering the implementation of biology-based patients’ classification models to describe the different MM clinical behaviors.

Immune profiles to predict bortezomib-based treatment response for multiple myeloma patients

BackgroundTo evaluate the distribution of bone marrow immune cell subsets and their correlation with treatment efficacy in patients with multiple myeloma (MM). MethodsWe analyzed the bone marrow lymphocyte subsets of 186 newly diagnosed MM patients at diagnosis and their correlation with clinical characteristics. In our study, eight-color flow cytometry, a method commonly used to detect plasma cell phenotypes, was used to analyze seven bone marrow immune cell groups by change gate-strategy. ResultsFirst, for all the 7 immune cell groups, the percentage of immature B cells was significantly lower in stage III patients than in stage I patients, while the trend was reversed in memory B cells in both the International Staging System(p = 0.004) and Revised International Staging System(p = 0.018). Second, the percentage of naïve B cells were significantly lower in patients with severe anemia, while the percentage of memory B cells had reversed trend. The percentage of immature B cells were lower in patients with Cr ≥ 2 mg/dL than in patients with Cr < 2 mg/dL. Then we followed the treatment efficacy of 152 patients who received four cycles of induction therapy (bortezomib + dexamethasone or bortezomib + lenalidomide + dexamethasone) and analyzed the relationship between bone marrow lymphocyte subsets at the initial stage and treatment response datasets. We found that both the percentage of B cells(p＜0.001) and immature B(p = 0.002) were increased in patients who achieved very good partial remission(VGPR) after four cycles of induction therapy. The ROC results indicated the combination of the multiple immune subgroups had predictive values (AUC = 0.802, p<0.001) in the treatment effect after four cycles of induction therapy. ConclusionsOverall, these results suggest that the analysis of lymphocyte subsets along with plasma cell immunophenotyping could be a potential index for determining the prognosis of MM patients.

Validation of the IMPEDE VTE score for prediction of venous thromboembolism in Chinese patients with multiple myeloma: A single-center retrospective cohort study

Multiple myeloma (MM) significantly increases the risk of venous thromboembolism (VTE) within 6 months of treatment initiation. The IMPEDE VTE score is a VTE risk prediction model which is recently incorporated into the National Comprehensive Cancer Network (NCCN) guidelines, but it lacks validation among Asians, including Chinese MM patients. We performed a retrospective chart review of 405 Chinese with newly diagnosed MM who started therapy at Beijing Jishuitan Hospital between April 2013 to October 2022. The 6-month cumulative incidence of VTE was 3.8 % (95 % CI:1.6–7.6), 8.6 % (95 % CI: 5.3–21.9) and 40.5 % (95 % CI: 24.9–55.7) in the low-, intermediate- and high-risk groups (P < 0.001), respectively. The C-statistic of the IMPEDE VTE scores for predicting VTE within 6 months of treatment initiation was 0.74 (95 % CI: 0.65–0.83). Of note, in this single-center cohort study, we propose that the anticoagulant LMWH may be more effective than the antiplatelet aspirin in potentially preventing VTE in newly diagnosed MM patients. Our findings suggest that the IMPEDE VTE score is a valid evidence-based risk stratification tool in Chinese patients with newly diagnosed MM.

68Ga]Pentixafor PET/CT for staging and prognostic assessment of newly diagnosed multiple myeloma: comparison to [18F]FDG PET/CT.

To evaluate the prognostic performance of [68Ga]Pentixafor PET/CT at baseline for staging of patients with newly diagnosed multiple myeloma (MM) and to compare it with [18F]FDG PET/CT and the Revised-International Staging System (R-ISS). Patients who underwent [68Ga]Pentixafor and [18F]FDG PET/CT imaging were retrospectively included. Patient staging was performed according to the Durie-Salmon PLUS staging system based on [68Ga]Pentixafor PET/CT and [18F]FDG PET/CT images, and the R-ISS. Progression-free survival (PFS) at patient follow-up was estimated using the Kaplan-Meier estimator and compared using the log-rank test. Area under the receiver operating characteristic curve (AUC) was calculated to assess predictive performance. Fifty-five MM patients were evaluated. Compared with [18F]FDG PET, [68Ga]Pentixafor PET detected 25 patients as the same stage, while 26 patients were upstaged and 4 patients were downstaged (P = 0.001). After considering the low-dose CT data, there was no statistically significant difference in the number of patients classified in each stage using [68Ga]Pentixafor PET/CT and [18F]FDG PET/CT (P = 0.091). [68Ga]Pentixafor PET/CT-based staging discriminated PFS outcomes in patients with different disease stages (stage I vs. stage II, stage I vs. stage III, and stage II vs. stage III; all P < 0.05), whereas for [18F]FDG PET/CT, there was only a difference in median PFS between stage I and III (P = 0.021). When staged by R-ISS, the median PFS for stage III was significantly lower than that for stage I and II (P = 0.008 and 0.035, respectively). When predicting 2-year PFS based on staging, the AUC of [68Ga]Pentixafor PET/CT was significantly higher than that of [68Ga]Pentixafor PET (0.923 vs. 0.821, P = 0.002), [18F]FDG PET (0.923 vs. 0.752 P = 0.002), and R-ISS (0.923 vs. 0.776, P = 0.005). [68Ga]Pentixafor PET/CT-based staging possesses substantial potential to predict disease progression in newly diagnosed MM patients.

Significance of Tim-3 and Its Ligand Galectin-9 in Th1/Th2 Imbalance in Patients with Multiple Myeloma

To investigate the significance of Tim-3 and Galectin-9 in Th1/Th2 imbalance in patients with multiple myeloma (MM). 55 newly diagnosed MM patients and 20 healthy controls were included. Flow cytometry was used to detect the expression of Tim-3 on CD4+T cells, the proportion of Th1, Th2, Tim-3+Th1 and Tim-3+Th2 cells in peripheral blood. ELISA was used to detect the levels of cytokines IFN-γ and IL-4 in serum, and PCR was used to detect the level of Galectin-9 mRNA. Then the correlations between Galectin-9 mRNA expression and Th-cell subsets and related cytokine levels, as well as the relationship between Tim-3+Th1/Tim-3+Th2 ratio and corresponding clinical features were analyzed. Compared with the control group, the expression of Tim-3 on CD4+T cells in peripheral blood of MM patients was significantly increased (P<0.05), the proportions of Tim-3+Th1 cells, Tim-3+Th2 cells and Tim-3+Th1/Tim-3+Th2 ratio in MM patients were also increased (P<0.05), while the proportion of Th1 cells and Th1/Th2 ratio in MM patients were significantly decreased (P<0.05). The level of cytokine IFN-γ and IFN-γ/IL-4 ratio in MM patients were significantly decreased (P<0.05), while the level of cytokine IL-4 was increased (P<0.05). The mRNA levels of Galectin-9 in MM patients were significantly increased (P<0.05). The levels of Galectin-9 mRNA were positively correlated with Tim-3+CD4+T cells (r=0.663), Tim-3+Th2 cells (r=0.492) and IL-4 (r=0.470), while negatively correlated with IFN-γ (r=-0.593). The ratios of Tim-3+Th1/Tim-3+Th2 in MM patients were positively correlated with ISS stage (r=0.511), osteolytic damage (r=0.556) and chromosome abnormality (r=0.632). These results suggest that Tim-3 and Galectin-9 are involved in Th1/Th2 imbalance in MM patients, and the high ratio of Tim-3+Th1/Tim-3+Th2 is associated with poor clinical prognosis.

Abstract B112: SNAP23-dependent SNARE complex is a novel molecular target in AL Amyloidosis and Multiple Myeloma by blocking free light chain secretion and triggering a terminal unfolded protein response

Abstract The goal of this study was to investigate whether SNARE proteins are necessary for immunoglobulin (Ig) free light chain (FLC) secretion, thus representing a yet unexplored therapeutic target in AL amyloidosis (AL) and Multiple myeloma (MM). Both these disorders are incurable, and in the former, pathogenesis is invariably related to deposition of Ig FLC fibrils in target organs. The molecular mechanisms underlying FLC folding/secretion have not been studied, and no therapies directly target this intrinsic vulnerability. We hypothesize that FLC secretion is at least in part mediated by SNARE proteins, and their inhibition would block FLC exocytosis, causing retention of FLC-loaded vesicles, leading to activation of a terminal unfolded protein response (UPR) and apoptosis. We therefore hypothesized that novel, effective targets for MM and AL therapy could be identified within SNAREs. As a tool to study SNARE function, we stably expressed 7 distinct, tetracycline-inducible botulinum neurotoxin (BoNT) serotypes (BoNT/A-F) in FLC-secreting AL (ALMC1, ALMC2) and MM (U266, KMS11) cell lines. To monitor BoNT expression, a bicistronic lentiviral vector with a P2A-GFP was used. Upon doxycycline administration, we performed growth competition assay in polyclonally transduced cells and assessed kinetics of GFP expression over time and apoptosis via flow cytometry in monoclones. Western blot (WB) was used to assess cleavage of SNAREs upon expression of each BoNT. We used WB and ELISA to assess FLC secretion on a per-cell base upon BoNT expression. We used TurboID proximity labeling followed by mass spectrometry to identify cytotoxic BoNT interacting partners and CRISPR-Cas9 gene editing to validate putative BoNT targets. By querying the IFM170 gene expression database of newly diagnosed MM patients, we identified VAMP2, VAMP3, SYNTAXIN4, and SNAP23 as the top expressed SNARE and confirmed their high expression in a panel of AL and MM cell lines. Expression of all BoNT serotypes, except BoNT B, led to rapid apoptosis of AL and MM cells, with BoNT F standing out for extent and rapidity of cytotoxicity. Concurrent cleavage of SNAP23, VAMP3, and SYNTAXIN4 correlated with cytotoxicity of BoNT in AL and MM cell lines. Mechanistically, we showed that cytotoxic BoNTs, but not BoNT B, blocked FLC secretion and triggered the PERK-mediated terminal UPR with induction of CHOP and GADD34 followed by massive apoptosis. We identified SNAP23 as an interacting partner of cytotoxic BoNT F, but not BoNT B. Single SNAP23 KO did not completely recapitulate cytotoxic BoNT phenotype, as it was only partially cytotoxic. Based on our preliminary data, we hypothesize SYNTAXIN4 and VAMP3 to be synthetic lethal with SNAP23. Our data provide proof of concept that blocking FLC secretion in AL and MM cells is feasible and results in rapid cell apoptosis by triggering a terminal UPR, thus representing a promising, novel therapeutic approach. Using BoNT as a biological tool, we identified SNAP23 as a critical component of FLC exocytosis, paving the way for the design of novel therapeutics. Citation Format: Emre Karayol, Maria Moscvin, Tianzeng Chen, Peter G. Czarnecki, Annamaria Gulla, Kenneth C. Anderson, Giada Bianchi. SNAP23-dependent SNARE complex is a novel molecular target in AL Amyloidosis and Multiple Myeloma by blocking free light chain secretion and triggering a terminal unfolded protein response [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B112.

Real-world multiple myeloma risk factors and outcomes by non-Hispanic Black/African American and non-Hispanic White race/ethnicity in the United States.

Examination of the impact of race and ethnicity on multiple myeloma (MM) outcomes has yielded inconsistent results. This retrospective, real-world (RW) study describes patient, disease, and treatment characteristics (and associations with survival outcomes) among newly diagnosed MM patients of non-Hispanic (NH) Black/African American (AA) and NH White race/ethnicity in the United States. We included patients from the nationwide Flatiron Health electronic health record-derived de-identified database who initiated first line of therapy (LOT) for MM between January 1, 2016 and March 31, 2022. Of 4,614 patients in our study cohort, 23.3% were NH Black/AA. Non-Hispanic Black/AA patients were younger than NH White patients at diagnosis (median 68 vs 71 years) and more likely to be female (53.4% vs 43.5%). Rates of high-risk cytogenetics and 1q21+ were similar between races/ethnicities. The most common primary regimen used was lenalidomide-bortezomib-dexamethasone (50.1% of NH Black/AA and 48.1% of NH White patients). Receipt of stem cell transplantation during first LOT was less common among NH Black/AA (16.5%) than NH White (21.9%) patients. Unadjusted RW progression-free survival (rwPFS) and overall survival (rwOS) were similar between races/ethnicities. After multivariable adjustment, NH Black/AA race/ethnicity was associated with slightly inferior rwPFS (hazard ratio [HR] 1.13; 95% CI 1.01-1.27). The difference in rwOS (HR 1.12; 95% CI 0.98-1.28) was not statistically significant. In general, associations between risk factors for rwPFS and rwOS were consistent between races/ethnicities. Findings from this analysis help to inform clinicians about the impact of race/ethnicity on MM treatment paradigms and outcomes in the United States.

Circulating Exosomal miRNA Signature As a Potential Risk Factor for DNA Virus Infection in Patients with Multiple Myeloma

Introduction DNA virus infection is a significant cause of morbidity and mortality in patients with multiple myeloma (MM). Monocyte dysfunction in MM patients plays a central role in infectious complications, but the precise molecular mechanism underlying the reduced monocyte resistance to viruses and risk factors for infection in newly diagnosed MM patients remains to be elucidated. Methods To determine the role of exosomal miRNAs in DNA infection of MM patients, we analyzed miRNAs in BM exosomes from MM patients (Exo-miRs) using high-throughput small RNA sequencing. To further evaluate the effect of these five upregulated Exo-miRs in antiviral response, we transfected the host cells with chemically synthesized miRNAs mimics to overexpress miRNAs. We utilized qPCR and WB to characterize the fate the cGAS-STING signaling pathway of THP-1 after overexpress miRNAs. The efficacy and safety of these Exo-miRs in innate antiviral immunity were evaluated using 5TGM1 C57BL/KaLwRij mice models. Additionally, miRNAs copy number as well as the viral susceptibility of newly diagnosed MM patients were determined in 82 samples from newly diagnosed biopsy proven MM patients. Results Screening of miRNAs enriched in exosomes delivered by primary MM cells identified five miRNAs as inhibitory factors that negatively regulate the cGAS-STING antiviral immune response. When engraftments of 5TGM1-Luc cells via tail vein for eight weeks in C57BL/KaLwRij mice resulted in MM progression with typical MM phenotypes, model mice were primed with Exo-miR antagomiRs oligonucleotides mixture through tail vein injection three times every 24 h followed by Murine cytomegalovirus (MCMV) challenge for 36 h. Consistent with the immunosuppression in MM patients, 5TGM1 C57BL/KaLwRij mice showed lower IFN-β in sera. Notably, intravenous administration of antagomiRs against miRNAs resulted in a marked increase of IFN-β levels in serum and IFN-I expression in organs (Figure 1). To investigate the potential of the miR-score as a prognostic determinant of vulnerability to DNA virus infection, we compared the miR-score in plasma exosomes collected from 82 newly diagnosed biopsy proven MM patients. We classified the viral susceptibility of newly diagnosed MM patients into two groups: I, DNA virus infection; II, no DNA virus infection. In human, a pronounced inverse correlation between IFN-β production by DNA virus in PBMCs and the microRNA (miR)-score of the exosomes within the plasma. The patients with DNA virus infection showed significantly enhanced circulatory expression of miRNAs than without DNA virus infection (p&amp;lt;0.001) patients. The diagnostic potential of miRNAs was assessed by plotting ROC curve, 5 miRNAs showed optimum sensitivity and specificity（AUC 0.854, P&amp;lt;0.0001, Sensitivity 87.5%, Specificity 74.1%, Cut-off values 5.234)（Figure 2）. Conclusions These findings identify a mechanism by which MM cells can suppress the host's innate immunity and potentially lead to immunocompromise in MM patients. Furthermore, the aberrant expression of specific miRNAs in MM patients emerges as a potential therapeutic target in MM cells. By quantifying miRNA scores based on abundant exosomal miRNAs in peripheral blood, the risk of DNA virus infection in MM patients can be assessed. Our findings shed light on a previously unknown molecular mechanism underlying immunosuppression in MM patients who have not received antineoplastic therapy, and also reveal a distinct miRNA signature that serves as a crucial determinant of the susceptibility of newly diagnosed MM patients to DNA virus infections.

The Role of Macrophage Migration Inhibitory Factor (MIF) in Regulation of T-Cell Activity in Multiple Myeloma

Background: Multiple myeloma (MM) is the second most common hematological malignancy associated with the overproduction of light chain or monoclonal immunoglobulin. MM remains incurable, with high relapses and refractory disease rates after first-line treatment. Hence, novel therapeutic approaches are needed to improve immune responses to prevent relapses or drug resistance after initial therapies. Immune responses are shaped by several factors, including mutations, pro- and anti-inflammatory cytokines and chemokines, and activation of immune checkpoints in the tumor microenvironment (TME) (Gonzalez et al., 2018). Macrophage migration inhibitory factor (MIF) as a soluble pro-inflammatory cytokine has become one of the most puzzling regulators of innate and adaptive immune responses. In myeloma, MIF was found to be significantly higher in MM cells from relapsed patients than those responding to the treatment. MIF has been implicated in drug resistance and suggested as a biomarker for predicting MM patient responses to proteasome inhibitors (Wang et al., 2020). We previously reported that MIF is highly expressed in MM and regulates CD84 (SLAMF5) expression in MM TME. We showed that MIF secreted from MM cells regulates PD-L1 expression through CD84 on CD14 + monocytic cells in the TME. Inhibition of MIF significantly reduced CD84 and PD-L1 expressions on human CD14 + cells and on myeloid-derived suppressor cells of the mice bearing MM (Lewinsky and Gunes et al., 2021). However, whether MIF directly regulates T-cell activity in MM TME has yet to be explored. Methods and Results: The current study reports that MIF may play a pivotal role in T-cell exhaustion in MM. Ouranalyses in published MM transcriptomic databases show that MM patients with low MIF had significantly longer overall and post-progression survival, indicating the therapeutic potential of MIF in MM. We also noted upregulated MIF gene expression in relapsed or refractory MM (R/RMM) patients (n=2) compared to that in newly diagnosed MM patients (n=7) and healthy individuals (n=9) in our and publicly available MM single-cell RNA sequencing datasets. We detected a profound MIF expression in MM cells and myeloid cell fractions, including monocytes, macrophages, and dendritic cells from the patients' bone marrow (BM) specimens. We previously reported that human MM cell lines highly express MIF. In this study, we assessed the impact of MIF secreted by MM cells on the immune cells, specifically CD8 + T cells. Our results showed that inhibition of MIF reduced the elevated T-cell exhaustion markers, PD1 and CTLA-4, on CD8 + T cells in healthy donors (HDs) peripheral blood mononuclear cells (PBMCs) following the coculturing with MM1.S cells (n=3 *P &amp;lt; 0.05 ). We also found that MIF inhibition induced the T-cell activation marker, LAMP1, on CD8 + T cells in this coculturing setting (n=3, **P &amp;lt; 0.01). Furthermore, we noted MIF inhibition reduced PD1 expression on CD8 + T cells in HDs PBMCs (n=3, **P &amp;lt; 0.01), suggesting MIF may regulate the exhaustion profile of CD8 + T cells. MIF can conduct paracrine or autocrine signalings by binding to its receptors, including CD74 and CD44, and lead to intracellular signaling cascades. Hence, we assessed CD74 gene expression as the counterpart of MIF in R/RMM, MM, and healthy patients. We noted significantly upregulated CD74 expression in R/RMM patients compared to newly diagnosed MM patients and healthy individuals. We also noted higher CD74 expression in CD8 + T cells than in CD4 + T cells in R/RMM patients, suggesting that MIF/CD74 axis may be a potential target to enhance CD8 + T cell-mediated immunity in R/RMM. To further explore the impact of MIF inhibition on MM progression, we performed a pilot in vivo study by inoculating murine 5TGM1 cells into two groups of syngeneic C57BL/KaLwRijHsd mice. After two weeks, the mice were injected with either sterile PBS as a control or a MIF inhibitor. The results of this pilot study showed that MIF inhibition significantly decreased MM cells in BM and PB of myeloma-bearing mice and reduced T-cell exhaustion markers on CD8 + T cells compared to that in the control mice (n=3-4, *P &amp;lt; 0.05, **P &amp;lt; 0.01, ***P &amp;lt; 0.001). Conclusion: Overall, our preliminary data indicate that MIF may have a crucial role in T-cell activity by regulating T-cell exhaustion markers in MM. Further studies are needed to explore the therapeutic potential of MIF to reduce T-cell exhaustion to improve anti-tumor immunity in MM.