Gastrointestinal toxicities of proteasome inhibitor therapy.

PURPOSE: Proteasome inhibitors (PIs), which cause cell death via tumor suppressor and pro-apoptotic proteins, are integral to treatment of many hematologic malignancies but are limited by their gastrointestinal adverse effects. Evidence regarding these PI-related adverse effects is scant. In this study, we evaluated gastrointestinal adverse events caused by PIs and compared gastrointestinal toxicities between bortezomib, carfilzomib, and ixazomib. METHODS: We conducted a retrospective study of cancer patients treated with PIs at a tertiary care cancer center to investigate the clinical characteristics of PI-related gastrointestinal adverse events. RESULTS: Our sample comprised 973 patients with PI exposure and stool studies ordered between January 2017 and December 2022. Of these, 193 patients (20%) had PI-related gastrointestinal toxicity based on clinical symptoms and stool study results. The most common symptom was diarrhea, present in 169 (88% of those with gastrointestinal toxicity). Twenty-two (11%) required hospitalization, and 71 (37%) developed recurrence of symptoms. Compared to bortezomib or carfilzomib, ixazomib had a longer interval from PI initiation to the onset of gastrointestinal symptoms (313 days vs 58 days vs 89 days, p = 0.002) and a significantly lower percentage of diarrhea-predominant presentation of gastrointestinal toxicity (71% vs 96% vs 91%, p = 0.048). CONCLUSION: While PI-related gastrointestinal toxicities have various presentations and courses based on different regimens, the vast majority of patients presented with milder disease behavior. Despite a considerably high rate of hospitalization and recurrence after treatment necessitating optimization of clinical management, our cohort demonstrates favorable outcomes without long-term consequences.

Molecular Long-Term Analysis of the GMMG-HD4 Trial in Multiple Myeloma-Patterns of Association of Chromosomal Aberrations with Response and Proliferation Determining Survival in Selecting Treatments in View of Limited Resources in Low- and Middle-Income Countries.

Based on the lack of differences in progression-free and overall survival after a median follow-up of 93 months in our HOVON-65/GMMG-HD4 trial (German part; n = 395) randomizing VAD induction (vincristin/adriamycin/dexamthasone)/tandem-transplantation/thalidomide-maintenance vs. PAD induction (bortezomib/adriamycin/dexamethasone)/tandem transplantation/bortezomib maintenance, we discern how chromosomal aberrations determine long-term prognosis by different patterns of association with proliferation and treatment-dependent response, whether responses achieved by different regimens are equal regarding prognosis, and whether subpopulations of patients could be defined as treatable without upfront "novel agents" in cases of limited resources, e.g., in low- or middle-income countries. Serum parameters and risk factors were assessed in 395 patients. CD138-purified plasma cells were subjected to fluorescence in situ hybridization (n = 354) and gene expression profiling (n = 204). We found chromosomal aberrations to be associated in four patterns with survival, proliferation, and response: deletion (del) del17p13, del8p21, del13q14, (gain) 1q21+, and translocation t(4;14) (all adverse) associate with higher proliferation. Of these, del17p is associated with an adverse response (pattern 1), and 1q21+, t(4;14), and del13q14 with a treatment-dependent better response (pattern 2). Hyperdiploidy associates with lower proliferation without impacting response or survival (pattern 3). Translocation t(11;14) has no association with survival but a treatment-dependent adverse response (pattern 4). Significantly fewer patients reach a near-complete response or better with "conventional" (VAD) vs. bortezomib-based treatment after induction or high-dose melphalan. These patients, however, show significantly better median progression-free and overall survival. Molecularly, patients responding to the two regimens differ in gene expression, indicating distinct biological properties of the responding myeloma cells. Patients with normal renal function (89.4%), low cytogenetic risk (72.5%), or low proliferation rate (37.9%) neither benefit in progression-free nor overall survival from bortezomib-based upfront treatment. We conclude that response level, the treatment by which it is achieved, and molecular background determine long-term prognosis. Chromosomal aberrations are associated in four patterns with proliferation and treatment-dependent responses. Associations with faster and deeper responses can be deceptive in the case of prognostically adverse aberrations 1q21+ and t(4;14). Far from advocating a return to "outdated" treatments, if resources do not permit state-of-the-art-treatment, normal renal function and/or molecular profiling identifies patient subpopulations doing well without upfront "novel agents".

Individualized dynamic frailty-tailored therapy (DynaFiT) in elderly patients with newly diagnosed multiple myeloma: a prospective study.

It remains a substantial challenge to balance treatment efficacy and toxicity in geriatric patients with multiple myeloma (MM), primarily due to the dynamic nature of frailty. Here, we conducted a prospective study to evaluate the feasibility and benefits of dynamic frailty-tailored therapy (DynaFiT) in elderly patients. Patients with newly diagnosed MM (aged ≥ 65 years) received eight induction cycles of bortezomib, lenalidomide, and dexamethasone (daratumumab was recommended for frail patients), with treatment intensity adjusted according to longitudinal changes in the frailty category (IMWG-FI) at each cycle. Of 90 patients, 33 (37%), 16 (18%), and 41 (45%) were fit, intermediate fit, and frail at baseline, respectively. Of 75 patients who had geriatric assessment at least twice, 28 (37%) experienced frailty category changes at least once. At analysis, 15/26 (58%) frail patients improved (27% became fit and 31% became intermediate fit), 4/15 (27%) intermediate fit patients either improved or deteriorated (two for each), and 6/30 (20%) fit patients deteriorated. During induction, 34/90 (38%) patients discontinued treatment, including 10/33 (30%) fit, 4/16 (25%) intermediate fit, and 20/41 (49%) frail; 14/40 (35%) frail patients discontinued treatment within the first two cycles, mainly because of non-hematologic toxicity (mostly infections). For fit, intermediate-fit, and frail patients, the overall response rate was 100%, 93%, and 73%, respectively; one-year overall survival was 90%, 75%, and 54%, respectively. Therefore, the individualized DynaFiT is feasible and promising for heterogeneous elderly patients.

A real-life study of daratumumab combinations in newly diagnosed patients with light chain (AL) amyloidosis.

Daratumumab-based regimens are the new standard of care for newly diagnosed patients with AL amyloidosis based on the results of the ANDROMEDA study. However, real-world data on daratumumab efficacy in upfront therapy in unselected patients are scanty. In the framework of a prospective observational study, we investigated the efficacy and safety of daratumumab in 88 newly diagnosed patients, including subjects with IIIb cardiac stage (26%) or myeloma defining events (29%). Daratumumab was administered with bortezomib in 50 (56%) patients, lenalidomide in 31 (35%), and monotherapy in 7 (8%). The rate of serious adverse events was low (16%). The overall hematologic response rate was 75% with 52 (59%) patients attaining at least a very good partial response (VGPR) at six months. Amongst patients evaluable for organ response, the rate of cardiac and renal responses at 6 months was 31% and 21%, respectively. Comparing stage IIIb patients with the remaining ones, the rate of profound hematologic response was not significantly different (≥VGPR 57% vs. 59%, p 0.955) likewise the rate of cardiac (33% vs. 30%, p 0.340) and renal (40% vs. 16%, p 0.908) responses. Daratumumab-based regimens demonstrated to be safe and effective in treatment-naïve AL amyloidosis even in advanced stage disease.

Toll-like receptor signaling in multiple myeloma cells promotes the expression of pro-survival genes B-cell lymphoma 2 and MYC and modulates the expression of B-cell maturation antigen.

Infections are common in plasma cell cancer multiple myeloma (MM) due to disease-related immune deficiencies and cancer treatment. Myeloma cells express Toll-like receptors (TLRs), and TLR activation has been shown to induce proliferative and pro-survival signals in cancer cells. MM is a complex and heterogeneous disease, and expression levels of TLRs as well as downstream signaling components are likely to differ between patients. Here, we show that in a large cohort of patients, TLR1, TLR4, TLR6, TLR9, and TLR10 are the most highly expressed in primary CD138+ cells. Using an MM cell line expressing TLR4 and TLR9 as a model, we demonstrate that TLR4 and TLR9 activation promoted the expression of well-established pro-survival and oncogenes in MM such as MYC, IRF4, NFKB, and BCL2. TLR4 and TLR9 activation inhibited the efficacy of proteasome inhibitors bortezomib and carfilzomib, drugs used in the treatment of MM. Inhibiting the autophagosome-lysosome protein degradation pathway by hydroxychloroquine (HCQ) diminished the protective effect of TLR activation on proteasome inhibitor-induced cytotoxicity. We also found that TLR signaling downregulated the expression of TNFRSF17, the gene encoding for B-cell maturation antigen (BCMA). MYC, BCL2, and BCL2L1 were upregulated in approximately 50% of primary cells, while the response to TLR signaling in terms of TNFRSF17 expression was dichotomous, as an equal fraction of patients showed upregulation and downregulation of the gene. While proteasome inhibitors are part of first-line MM treatment, several of the new anti-MM immune therapeutic drugs target BCMA. Thus, TLR activation may render MM cells less responsive to commonly used anti-myeloma drugs.

Guillain-Barr Syndrome Caused by Cytomegalovirus after Multiple Myeloma Treatment.

BACKGROUND: Both humoral and cell-mediated immunity of the patient affected by multiple myeloma (MM) are impaired; thus, infection is the main cause of the onset of symptoms and death caused by MM. Bortezomib is a first-line drug approved for patients with multiple myeloma (MM) and has significantly increased their overall survival. However, bortezomib-induced peripheral neuropathy (PN) remains a significant side effect that has led to its discontinuation in some patients. Guillain-Barre syndrome (GBS) is thought to be related to immune damage, and most patients have cytomegalovirus (CMV), Epstein-Barr virus (EBV), or mycoplasma infection before onset. Cases of GBS secondary to MM are rare. METHODS: We provide a case of GBS caused by cytomegalovirus infection after MM treatment, and briefly review the existing literature. RESULTS: Secondary GBS after MM. This patient received active treatment. The clinical symptoms are gradually improving. CONCLUSIONS: The use of bortezomib has the risk of reactivating the virus. It is more about the reactivation of hep-atitis B virus. Nonetheless, cytomegalovirus and Epstein-Barr virus shall have our attention. Patients with MM need to monitor CMV, regularly, especially during the treatment of bortezomib. At the same time, they also need to closely monitor the symptoms and signs of the nervous system to guard against the occurrence of GBS.

The efficacy of Bortezomib-based regimens on survival state in newly diagnosed multiple myeloma patients.

The prognosis of patients with multiple myeloma (MM) has significantly improved over the past ten years because of several innovative treatments, including the proteasome inhibitor Bortezomib and immunomodulatory drugs (IMiDs) like Thalidomide and Lenalidomide. The present study aimed to determine the effectiveness of Bortezomib-based regimens on survival state of MM patients. This retrospective study included 204 newly diagnosed MM patients who were registered at Nanakali Hospital for Blood Diseases and Cancer, Erbil- Iraq, between April 2008 and April 2022. The patients were split into two primary groups: those receiving treatment with Bortezomib and those not. Clinical and laboratory data, treatment type, responsiveness to induction therapy, and survival results were examined in the enrolled patients' medical records. The mean patient age was 60 years, males constituted 55.8% of the included patients. At the time of diagnosis, 98 individuals (48%) had stage 3 illness. Except for the LDH, which was noticeably higher in the non-Bortezomib group, the patients laboratory results did not substantially change between the Bortezomib and non-Bortezomib groups (p = 0.001). In patients treated with Bortezomib, the complete response (CR) rate following induction was substantially greater (35.2%) than in those treated without Bortezomib (9.1%). Compared to the non-Bortezomib group, the median survival time of the Bortezomib group was considerably greater (p < 0.001). Bortezomib has a significant role in inducing a CR before bone marrow (BM) transplantation, and it has a significant role in the survival outcome in MM.

PTEN status determines therapeutic vulnerability to celastrol in cholangiocarcinoma.

BACKGROUND: A balanced protein homeostasis network helps cholangiocarcinoma (CCA) maintain their oncogenic growth, and disrupting proteostasis therapeutically will induce proteotoxic stress. Phosphatase and tensin homolog (PTEN) have been reported to be involved in proteostasis, and PTEN-associated pathways are commonly altered in CCA. Celastrol, a triterpene from plants, exhibits cytotoxic effects in various types of cancer. However, the underlying mechanisms remain unclear. PURPOSE: We investigated the therapeutic effect of celastrol in CCA and identified the molecular characteristics of tumors that were sensitive to celastrol. The target of celastrol was explored. We then evaluated the candidate combination therapeutic strategy to increase the effectiveness of celastrol in celastrol-insensitive CCA tumors. METHODS: Various CCA cells were categorized as either celastrol-sensitive or celastrol-insensitive based on their response to celastrol. The molecular characteristics of cells from different groups were determined by RNA-seq. PTEN status and its role in proteasome activity in CCA cells were investigated. The CMAP analysis, molecular docking, and functional assay were performed to explore the effect of celastrol on proteasome activities. The correlation between PTEN status and clinical outcomes, as well as proteasomal activity, were measured in CCA patients. The synergistic therapeutic effect of autophagy inhibitors on celastrol-insensitive CCA cells were measured. RESULTS: Diverse responses to celastrol were observed in CCA cells. PTEN expression varied among different CCA cells, and its status could impact cell sensitivity to celastrol: PTENhigh tumor cells were resistant to celastrol, while PTENlow cells were more sensitive. Celastrol induced proteasomal dysregulation in CCA cells by directly targeting PSMB5. Cells with low PTEN status transcriptionally promoted proteasome subunit expression in an AKT-dependent manner, making these cells more reliant on proteasomal activities to maintain proteostasis. This caused the PTENlow CCA cells sensitive to celastrol. A negative correlation was found between PTEN levels and the proteasome signature in CCA patients. Moreover, celastrol treatment could induce autophagy in PTENhigh CCA cells. Disrupting the autophagic pathway in PTENhigh CCA cells enhanced the cytotoxic effect of celastrol. CONCLUSION: PTEN status in CCA cells determines their sensitivity to celastrol, and autophagy inhibitors could enhance the anti-tumor effect in PTENhigh CCA.

WTAP and m6A-modified circRNAs modulation during stress response in acute myeloid leukemia progenitor cells.

N6-methyladenosine (m6A) is one of the most prevalent and conserved RNA modifications. It controls several biological processes, including the biogenesis and function of circular RNAs (circRNAs), which are a class of covalently closed-single stranded RNAs. Several studies have revealed that proteotoxic stress response induction could be a relevant anticancer therapy in Acute Myeloid Leukemia (AML). Furthermore, a strong molecular interaction between the m6A mRNA modification factors and the suppression of the proteotoxic stress response has emerged. Since the proteasome inhibition leading to the imbalance in protein homeostasis is strictly linked to the stress response induction, we investigated the role of Bortezomib (Btz) on m6A regulation and in particular its impact on the modulation of m6A-modified circRNAs expression. Here, we show that treating AML cells with Btz downregulated the expression of the m6A regulator WTAP at translational level, mainly because of increased oxidative stress. Indeed, Btz treatment promoted oxidative stress, with ROS generation and HMOX-1 activation and administration of the reducing agent N-acetylcysteine restored WTAP expression. Additionally, we identified m6A-modified circRNAs modulated by Btz treatment, including circHIPK3, which is implicated in protein folding and oxidative stress regulation. These results highlight the intricate molecular networks involved in oxidative and ER stress induction in AML cells following proteotoxic stress response, laying the groundwork for future therapeutic strategies targeting these pathways.

[Efficacy of a Daltuzumab-containing Regimen in Patients with mSMART High-Risk Multiple Myeloma].

OBJECTIVE: To investigate the efficacy and safety of a treatment regimen based on daratumumab in patients with high-risk relapsed refractory multiple myeloma(MM) with mSMART 3.0 score. METHODS: Clinical data were collected from 16 patients with mSMART3.0 score high-risk relapsed refractory MM treated at the Affiliated Hospital of Shandong University of Traditional Chinese Medicine from May 2020 to May 2023, all of whom received daltezumab-based regimen (regimen drugs including dexamethasone, isazomib, bortezomib, lenalidomide). The efficacy and safety of the treatment were retrospectively analyzed. RESULTS: The median age of 16 patients was 63.5 (47-70) years old, including 10 cases of IgG type, 2 cases of IgA type, and 4 cases of light chain type. The curative efficacy was judged in all 16 patients, with an overall response rate of 93.75% (15/16), including 4 cases of strict complete remission (sCR), 1 case of complete remission (CR), 2 case of very good partial remission (VGPR), partial remission (PR) in 5 cases, and minor remission (MR) in 3 cases. The median follow-up time was 11(2-30) months, and the median progression-free survival and median overall survival were not achieved in 16 patients at the median follow-up period. The hematologic adverse effects of the treatment regimen using daratumumab-based were mainly neutropenia, and the non-hematologic adverse effects were mainly infusion-related adverse reactions and infections. CONCLUSION: Daratumumab-based regimen for the treatment of relapsed refractory MM patients with high risk of mSMART3.0 score has better efficacy and safety.

Anti-Leukemic Effects of Small Molecule Inhibitor of c-Myc (10058-F4) on Chronic Myeloid Leukemia Cells.

BACKGROUND: As one of the main molecules in BCR-ABL signaling, c-Myc acts as a pivotal key in disease progression and disruption of long-term remission in patients with CML. OBJECTIVES: To clarify the effects of c-Myc inhibition in CML, we examined the anti-tumor property of a well-known small molecule inhibitor of c-Myc 10058-F4 on K562 cell line. METHODS: This experimental study was conducted in K562 cell line for evaluation of cytotoxic activity of 10058-F4 using Trypan blue and MTT assays. Flow cytometry and Quantitative RT-PCR analysis were also conducted to determine its mechanism of action. Additionally, Annexin/PI staining was performed for apoptosis assessment. RESULTS: The results of Trypan blue and MTT assay demonstrated that inhibition of c-Myc, as shown by suppression of c-Myc expression and its associated genes PP2A, CIP2A, and hTERT, could decrease viability and metabolic activity of K562 cells, respectively. Moreover, a robust elevation in cell population in G1-phase coupled with up-regulation of p21 and p27 expression shows that 10058-F4 could hamper cell proliferation, at least partly, through induction of G1 arrest. Accordingly, we found that 10058-F4 induced apoptosis via increasing Bax and Bad; In contrast, no significant alterations were observed NF-KB pathway-targeted anti-apoptotic genes in the mRNA levels. Notably, disruption of the NF-κB pathway with bortezomib as a common proteasome inhibitor sensitized K562 cells to the cytotoxic effect of 10058-F4, substantiating the fact that the NF-κB axis functions probably attenuate the K562 cells sensitivity to c-Myc inhibition. CONCLUSIONS: It can be concluded from the results of this study that inhibition of c-Myc induces anti-neoplastic effects on CML-derived K562 cells as well as increases the efficacy of imatinib. For further insight into the safety and effectiveness of 10058-F4 in CML, in vivo studies will be required.

Characteristics and outcomes of patients developing pulmonary hypertension associated with proteasome inhibitors.

BACKGROUND: Pulmonary arterial hypertension (PAH) has been described in patients treated with proteasome inhibitors (PIs). Our objective was to evaluate the association between PIs and PAH. METHODS: Characteristics of incident PAH cases previously treated with carfilzomib or bortezomib were analysed from the French pulmonary hypertension registry and the VIGIAPATH programme from 2004 to 2023, concurrently with a pharmacovigilance disproportionality analysis using the World Health Organization (WHO) global database (VigiBase) and a meta-analysis of randomised controlled trials. RESULTS: 11 incident cases of PI-associated PAH were identified (six with carfilzomib and five with bortezomib) with a female:male ratio of 2.7:1, a median age of 61 years, and a median delay between PI first exposure and PAH of 6 months. Four patients died (two from right heart failure, one from respiratory distress and one from an unknown cause). At diagnosis, six were in New York Heart Association Functional Class III/IV with severe haemodynamic impairment (median mean pulmonary arterial pressure 39 mmHg, cardiac index 2.45 L·min-1·m-2 and pulmonary vascular resistance 7.2 WU). In the WHO pharmacovigilance database, 169 cases of PH associated with PI were reported since 2013 with significant signals of disproportionate reporting (SDR) for carfilzomib, regardless of the definition of cases or control group. However, SDR for bortezomib were inconsistent. The systematic review identified 17 clinical trials, and carfilzomib was associated with a significantly higher risk of dyspnoea, severe dyspnoea and PH compared with bortezomib. CONCLUSION: PIs may induce PAH in patients undergoing treatment, with carfilzomib emitting a stronger signal than bortezomib, and these patients should be monitored closely.

Impact of prior treatment on selinexor, bortezomib, dexamethasone outcomes in patients with relapsed/refractory multiple myeloma: Extended follow-up subgroup analysis of the BOSTON trial.

OBJECTIVES: To analyze the impact of prior therapies on outcomes with selinexor, bortezomib, and dexamethasone (SVd) versus bortezomib and dexamethasone (Vd) in 402 patients with relapsed/refractory multiple myeloma (RRMM) in the phase 3 BOSTON trial. METHODS: Post hoc analysis of progression-free survival (PFS), overall survival (OS), and safety for lenalidomide-refractory, proteasome inhibitor (PI)-naïve, bortezomib-naïve, and one prior line of therapy (1LOT) patient subgroups. RESULTS: At a median follow-up of over 28 months, clinically meaningful improvements in PFS were noted across all groups with SVd. The median SVd PFS was longer in all subgroups (lenalidomide-refractory: 10.2 vs. 7.1 months, PI-naïve: 29.5 vs. 9.7; bortezomib-naïve: 29.5 vs. 9.7; 1LOT: 21.0 vs. 10.7; p < .05). The lenalidomide-refractory subgroup had longer OS with SVd (26.7 vs. 18.6 months; HR 0.53; p = .015). In all subgroups, overall response and ≥very good partial response rates were higher with SVd. The manageable safety profile of SVd was similar to the overall patient population. CONCLUSIONS: With over 2 years of follow-up, these clinically meaningful outcomes further support the use of SVd in patients who are lenalidomide-refractory, PI-naïve, bortezomib-naïve, or who received 1LOT (including a monoclonal antibody) and underscore the observed synergy between selinexor and bortezomib.

The efficacy and tolerability of bortezomib, thalidomide, and dexamethasone induction therapy with a thalidomide dose step-up strategy in patients with newly diagnosed multiple myeloma: A prospective observational study.

BACKGROUND: Thalidomide-containing regimens cause adverse events (AEs) that may require a reduction in treatment intensity or even treatment discontinuation in patients with multiple myeloma. As thalidomide toxicity is dose-dependent, identifying the most appropriate dose for each patient is essential. AIMS: This study aimed to investigate the effects of a thalidomide dose step-up strategy on treatment response and progression-free survival (PFS). METHODS AND RESULTS: This prospective observational study included 93 patients with newly diagnosed multiple myeloma (NDMM) who received bortezomib, thalidomide, and dexamethasone (VTD). The present study assessed the incidence of thalidomide dose reduction and discontinuation, the overall dose intensity, and their effects on therapeutic efficacy. Furthermore, this study used Cox proportional hazard models to analyze the factors contributing to thalidomide intolerability. The results showed the overall response rates in all patients and the evaluable patients were 78.5% and 98.7%, respectively. The median PFS in the study cohort was not reached. The most common thalidomide-related AEs were constipation (32.3%) and skin rash (23.7%), resulting in dose reduction and discontinuation rates of 22.6% and 21.5%, respectively. The responders had a significantly higher average thalidomide dose intensity than the nonresponders (88.6% vs. 42.9%, p < .001). CONCLUSION: The thalidomide dose step-up approach is a viable option for patients with NDMM receiving VTD induction therapy with satisfactory efficacy and tolerability. However, thalidomide intolerance may lead to dose reduction or discontinuation due to unpredictable AEs, leading to lower dose intensity and potentially inferior treatment outcomes. In addition to a dose step-up strategy, optimal supportive care is critical for patients with multiple myeloma receiving VTD induction therapy.

Reduction of Filamin C Results in Altered Proteostasis, Cardiomyopathy, and Arrhythmias.

BACKGROUND: Many cardiomyopathy-associated FLNC pathogenic variants are heterozygous truncations, and FLNC pathogenic variants are associated with arrhythmias. Arrhythmia triggers in filaminopathy are incompletely understood. METHODS AND RESULTS: We describe an individual with biallelic FLNC pathogenic variants, p.Arg650X and c.970-4A>G, with peripartum cardiomyopathy and ventricular arrhythmias. We also describe clinical findings in probands with FLNC variants including Val2715fs87X, Glu2458Serfs71X, Phe106Leu, and c.970-4A>G with hypertrophic and dilated cardiomyopathy, atrial fibrillation, and ventricular tachycardia. Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) were generated. The FLNC truncation, Arg650X/c.970-4A>G, showed a marked reduction in filamin C protein consistent with biallelic loss of function mutations. To assess loss of filamin C, gene editing of a healthy control iPSC line was used to generate a homozygous FLNC disruption in the actin binding domain. Because filamin C has been linked to protein quality control, we assessed the necessity of filamin C in iPSC-CMs for response to the proteasome inhibitor bortezomib. After exposure to low-dose bortezomib, FLNC-null iPSC-CMs showed an increase in the chaperone proteins BAG3, HSP70 (heat shock protein 70), and HSPB8 (small heat shock protein B8) and in the autophagy marker LC3I/II. FLNC null iPSC-CMs had prolonged electric field potential, which was further prolonged in the presence of low-dose bortezomib. FLNC null engineered heart tissues had impaired function after low-dose bortezomib. CONCLUSIONS: FLNC pathogenic variants associate with a predisposition to arrhythmias, which can be modeled in iPSC-CMs. Reduction of filamin C prolonged field potential, a surrogate for action potential, and with bortezomib-induced proteasome inhibition, reduced filamin C led to greater arrhythmia potential and impaired function.

Bortezomib restrains M2 polarization and reduces CXCL16-associated CXCR6+CD4 T cell chemotaxis in bleomycin-induced pulmonary fibrosis.

BACKGROUND: The development of pulmonary fibrosis involves a cascade of events, in which inflammation mediated by immune cells plays a pivotal role. Chemotherapeutic drugs have been shown to have dual effects on fibrosis, with bleomycin exacerbating pulmonary fibrosis and bortezomib alleviating tissue fibrotic processes. Understanding the intricate interplay between chemotherapeutic drugs, immune responses, and pulmonary fibrosis is likely to serve as the foundation for crafting tailored therapeutic strategies. METHODS: A model of bleomycin-induced pulmonary fibrosis was established, followed by treatment with bortezomib. Tissue samples were collected for analysis of immune cell subsets and functional assessment by flow cytometry and in vitro cell experiments. Additionally, multi-omics analysis was conducted to further elucidate the expression of chemokines and chemokine receptors, as well as the characteristics of cell populations. RESULTS: Here, we observed that the expression of CXCL16 and CXCR6 was elevated in the lung tissue of a pulmonary fibrosis model. In the context of pulmonary fibrosis or TGF-ß1 stimulation in vitro, macrophages exhibited an M2-polarized phenotype and secreted more CXCL16 than those of the control group. Moreover, flow cytometry revealed increased expression levels of CD69 and CXCR6 in pulmonary CD4 T cells during fibrosis progression. The administration of bortezomib alleviated bleomycin-induced pulmonary fibrosis, accompanied by reduced ratio of M2-polarized macrophages and decreased accumulation of CD4 T cells expressing CXCR6. CONCLUSIONS: Our findings provide insights into the key immune players involved in bleomycin-induced pulmonary fibrosis and offer preclinical evidence supporting the repurposing strategy and combination approaches to reduce lung fibrosis.

Bortezomib for antibody-mediated rejection of kidney transplant in youth: Associations with donor-specific antibody.

BACKGROUND: Antibody-mediated rejection is one of the most significant risk factors for allograft dysfunction and failure in children and adolescents with kidney transplants, yet optimal treatment remains unidentified. To date, there are mixed findings regarding the use of Bortezomib, a plasma cell apoptosis inducer, as an adjunct therapy in the treatment of antibody-mediated rejection. METHODS: In a retrospective single center study, we reviewed the efficacy and tolerability of bortezomib as adjunct therapy for treatment-refractory antibody-mediated rejection. RESULTS: Six patients with a median age of 14.6 years (range 6.9-20.1 years) received bortezomib at a mean of 71 months (range 15-83 months) post-kidney transplant. Four patients experienced decline in estimated glomerular filtration rate (eGFR) from 4% to 42%. One patient started bortezomib while on hemodialysis and did not recover graft function, and another patient progressed to hemodialysis 6 months after receiving bortezomib. Although DSA did not completely resolve, there was a statistically significant decline in DSA MFI pre and 12-months post-BZ (p = .012, paired t-test) for the subjects who were not on dialysis at the time of bortezomib. Chronic Allograft Damage Index (CADI) score of ≥3 was seen in all six subjects at their biopsy prior to therapy. No adverse effects were reported. CONCLUSIONS: Bortezomib was well tolerated and resulted in improvements in MFI of DSA among four pediatric subjects without allograft failure, although no effects were observed on eGFR trajectory. Further studies are needed to clarify whether earlier intervention with bortezomib could prevent renal failure progression.

Daratumumab and antineoplastic therapy versus antineoplastic therapy only for adults with newly diagnosed multiple myeloma ineligible for transplant.

BACKGROUND: Multiple myeloma (MM) is a haematological malignancy that is characterised by proliferation of malignant plasma cells in the bone marrow. For adults ineligible to receive high-dose chemotherapy and autologous stem cell transplant, the recommended treatment combinations in first-line therapy generally consist of combinations of alkylating agents, immunomodulatory drugs, and proteasome inhibitors. Daratumumab is a CD38-targeting, human IgG1k monoclonal antibody recently developed and approved for the treatment of people diagnosed with MM. Multiple myeloma cells uniformly over-express CD-38, a 46-kDa type II transmembrane glycoprotein, making myeloma cells a specific target for daratumumab. OBJECTIVES: To determine the benefits and harms of daratumumab in addition to antineoplastic therapy compared to antineoplastic therapy only for adults with newly diagnosed MM who are ineligible for transplant. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, EU Clinical Trials Register, ClinicalTrials.gov, WHO ICTRP, and conference proceedings from 2010 to September 2023. SELECTION CRITERIA: We included randomised controlled trials that compared treatment with daratumumab added to antineoplastic therapy versus the same antineoplastic therapy alone in adult participants with a confirmed diagnosis of MM. We excluded quasi-randomised trials and trials with less than 80% adult participants, unless there were subgroup analyses of adults with MM. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the results of the search strategies for eligibility. We documented the process of study selection in a flowchart as recommended by the PRISMA statement. We evaluated the risk of bias in included studies with RoB 1 and assessed the certainty of the evidence using GRADE. We followed standard Cochrane methodological procedures. MAIN RESULTS: We included four open-label, two-armed randomised controlled trials (34 publications) involving a total of 1783 participants. The ALCYONE, MAIA, and OCTANS trials were multicentre trials conducted worldwide in middle- and high-income countries. The AMaRC 03-16 trial was conducted in one high-income country, Australia. The mean age of participants was 69 to 74 years, and the proportion of female participants was between 40% and 54%. All trials evaluated antineoplastic therapies with or without daratumumab. In the ALCYONE and OCTANS trials, daratumumab was combined with bortezomib and melphalan-prednisone. In the AMaRC 03-16 study, it was combined with bortezomib, cyclophosphamide, and dexamethasone, and in the MAIA study, it was combined with lenalidomide and dexamethasone. None of the included studies was blinded (high risk of performance and detection bias). One study was published as abstract only, therefore the risk of bias for most criteria was unclear. The other three studies were published as full texts. Apart from blinding, the risk of bias was low for these studies. Overall survival Treatment with daratumumab probably increases overall survival when compared to the same treatment without daratumumab (hazard ratio (HR) 0.64, 95% confidence interval (CI) 0.53 to 0.76, 2 studies, 1443 participants, moderate-certainty evidence). After a follow-up period of 36 months, 695 per 1000 participants survived in the control group, whereas 792 per 1000 participants survived in the daratumumab group (95% CI 758 to 825). Progression-free survival Treatment with daratumumab probably increases progression-free survival when compared to treatment without daratumumab (HR 0.48, 95% CI 0.39 to 0.58, 3 studies, 1663 participants, moderate-certainty evidence). After a follow-up period of 24 months, progression-free survival was reached in 494 per 1000 participants in the control group versus 713 per 1000 participants in the daratumumab group (95% CI 664 to 760). Quality of life Treatment with daratumumab may result in a very small increase in quality of life after 12 months, evaluated on the EORTC QLQ-C30 global health status scale (GHS), when compared to treatment without daratumumab (mean difference 2.19, 95% CI -0.13 to 4.51, 3 studies, 1096 participants, low-certainty evidence). The scale is from 0 to 100, with a higher value indicating a better quality of life. On-study mortality Treatment with daratumumab probably decreases on-study mortality when compared to treatment without daratumumab (risk ratio (RR) 0.72, 95% CI 0.62 to 0.83, 3 studies, 1644 participants, moderate-certainty evidence). After the longest follow-up available (12 to 72 months), 366 per 1000 participants in the control group and 264 per 1000 participants in the daratumumab group died (95% CI 227 to 304). Serious adverse events Treatment with daratumumab probably increases serious adverse events when compared to treatment without daratumumab (RR 1.18, 95% CI 1.02 to 1.37, 3 studies, 1644 participants, moderate-certainty evidence). After the longest follow-up available (12 to 72 months), 505 per 1000 participants in the control group versus 596 per 1000 participants in the daratumumab group experienced serious adverse events (95% CI 515 to 692). Adverse events (Common Terminology Criteria for Adverse Events (CTCAE) grade ≥ 3) Treatment with daratumumab probably results in little to no difference in adverse events (CTCAE grade ≥ 3) when compared to treatment without daratumumab (RR 1.01, 95% CI 0.99 to 1.02, 3 studies, 1644 participants, moderate-certainty evidence). After the longest follow-up available (12 to 72 months), 953 per 1000 participants in the control group versus 963 per 1000 participants in the daratumumab group experienced adverse events (CTCAE grade ≥ 3) (95% CI 943 to 972). Treatment with daratumumab probably increases the risk of infections (CTCAE grade ≥ 3) when compared to treatment without daratumumab (RR 1.52, 95% CI 1.30 to 1.78, 3 studies, 1644 participants, moderate-certainty evidence). After the longest follow-up available (12 to 72 months), 224 per 1000 participants in the control group versus 340 per 1000 participants in the daratumumab group experienced infections (CTCAE grade ≥ 3) (95% CI 291 to 399). AUTHORS' CONCLUSIONS: Overall analysis of four studies showed a potential benefit for daratumumab in terms of overall survival and progression-free survival and a slight potential benefit in quality of life. Participants treated with daratumumab probably experience increased serious adverse events. There were likely no differences between groups in adverse events (CTCAE grade ≥ 3); however, there are probably more infections (CTCAE grade ≥ 3) in participants treated with daratumumab. We identified six ongoing studies which might strengthen the certainty of evidence in a future update of this review.