Search Results (364)

Background: Colorectal cancer (CRC) remains a significant global health burden, with KRAS mutations driving ~40% of cases. The efficacy of recently approved, mutant-specific KRAS inhibitors is limited by mutational status as well as intrinsic and adaptive resistance mechanisms. Pan-RAS inhibitors, such as ADT-007, offer broader therapeutic potential by targeting multiple RAS isoforms. Here, we evaluate ADT-007 in 3D bioprinted ex vivo slice tissue (BEST) generated from KRAS-mutant and RAS wild-type (WT) CRC cell lines. Methods: Potency and selectivity of ADT-007 were benchmarked against bortezomib (proteasome inhibitor) and YM155 (survivin inhibitor) using high-content imaging and ATP-based luminescence assays. Apoptosis induction was assessed with Annexin V/propidium iodide and flow cytometry. Results: ADT-007 exhibited high potency and selectivity in KRAS-mutant BEST, reducing tumor burdens >30% at nanomolar concentrations, and demonstrated superior selectivity with minimal cytotoxicity in WT RAS BEST. Annexin V staining confirmed selective induction of apoptosis in KRAS-mutant cells. Conclusions: The selective potency and specificity of ADT-007 warrant further investigation of pan-RAS inhibitors for treating RAS-driven cancers. This study also underscores the translational utility of 3D BEST models for preclinical drug response assessment. Further validation in patient-derived BEST is necessary to evaluate the potential of ADT-007 in clinical settings. Full article

Multiple myeloma (MM) is a kind of plasma cell neoplasm, accounting for approximately 10% of hematologic malignancies, with a high mortality rate. Apigenin (APG), a flavonoid, has been reported to have antiviral, antibacterial, antioxidant, and anticancer properties. However, the impact of APG on MM and bortezomib (BTZ) sensitization has not been investigated. The effects of APG on the proliferation, cell cycle, apoptosis, and oxidative stress of RPMI-8226 and U266 cells were investigated using CCK-8 assay, crystal violet staining, flow cytometry, Western blot, and PCR. It was observed that APG treatment increased the G1 phase cells, by which the expression of P21 increased, and the expression of CDK2 and Cyclin D1 decreased. Even though Necrostatin-1 (a potent necroptosis inhibitor) and Fer-1 (a ferroptosis inhibitor) could attenuate the effect of APG, the effect of Z-VAD-FMK (a pan-caspase inhibitor) was more significant. APG treatment increased the transcription of P53 and BAX, and the level of cleaved-PARP1 and cleaved-Caspase 3 in two MM cell strains. In addition, the APG application could dose-dependently increase the ROS, MDA, and GSSH levels, and decrease the GSH level in both cell strains, by which the transcription of GCLC, NQO1, GSTM2, NRF2, and GPX4 were attenuated. Finally, APG enhances the inhibitory effect of BTZ on MM cell growth. This study provides a potential therapeutic approach of APG on MM. Full article

This report presents the case of a seven-year-old West Highland White Terrier diagnosed with relapsed and refractory multiple myeloma (MM), managed using multiple treatment approaches, including conventional chemotherapy (melphalan, vincristine, doxorubicin, and dexamethasone), radiation therapy (RT), and novel agents such as the selective inhibitor of nuclear export (verdinexor), proteasome inhibitors (bortezomib, carfilzomib, and ixazomib), and tyrosine kinase inhibitors (TKIs; toceranib and sorafenib). Treatment response was monitored using serum globulin concentration and imaging studies. Verdinexor achieved the longest period of stable remission with minimal toxicity post-RT. Bortezomib + dexamethasone was effective in controlling hyperglobulinemia at doses ≥ 1.45 mg/m², although cumulative hematologic and gastrointestinal toxicity limited its prolonged use. Second-line proteasome inhibitors and TKIs demonstrated limited efficacy. Despite initial therapeutic response, the patient’s condition deteriorated due to persistent hyperglobulinemia and hyperviscosity syndrome. The absence of advanced supportive options, including plasmapheresis, contributed to a fatal outcome. This case highlights the potential utility of novel therapies such as verdinexor and bortezomib in managing refractory canine MM. Timely intervention, individualized dosing, and supportive care are essential for optimizing treatment outcomes. Further research is required to define effective combinations and integrate advanced care options, including stem cell transplantation and targeted antibody therapies, in veterinary MM. Full article

Introduction: Despite the approval of novel agents that have significantly improved long-term survival rates for multiple myeloma (MM) patients undergoing autologous stem cell transplant (ASCT), most patients eventually relapse. The failure to achieve or maintain bone marrow (BM) minimal residual disease (MRD) negativity is a recognised adverse prognostic factor for progression-free survival (PFS) and overall survival (OS). Contamination of stem cell apheresis by clonal plasma cells may also affect prognosis, though data remain limited. Methods: We conducted a prospective, single-centre observational study including 100 newly diagnosed MM patients eligible for ASCT and treated with bortezomib-based triplet induction. MRD was assessed both on BM and apheresis samples using multiparameter flow cytometry (MFC-MRD) with a sensitivity of 10⁻⁵. Results: Clonal plasma cells were detected in 22 apheresis samples (aMRD+), all of which were associated with BM MRD positivity. Patients with aMRD+ had inferior pre-ASCT responses (≥VGPR: 10% vs. 63%, p = 0.005) and worse post-ASCT BM MRD negativity rates (4% vs. 49%, p = 0.048). After a median follow-up of 52.4 months, aMRD+ was associated with shorter progression-free survival (median 38.5 vs. not reached, p = 0.007) and overall survival (median 60 months vs. not reached, p = 0.003). Conclusions: Contamination of the apheresis product is associated with persistent BM disease and poorer outcomes. Combined MRD assessment in both bone marrow and apheresis may improve risk stratification in MM patients undergoing ASCT. Full article

Sickle cell disease (SCD) is a prevalent genetic disorder caused by a mutation in the beta-globin gene. Hyperhemolysis (HS) is a severe complication involving the rapid destruction of both transfused and endogenous red blood cells, commonly found in SCD. This literature review explores the clinical presentation, diagnosis, pathogenesis, and management of HS in SCD. HS can manifest acutely or in a delayed manner, complicating diagnosis due to overlapping symptoms and varying reticulocyte responses. Immunohematological assessments often reveal delayed positivity in direct antiglobulin tests and antibody screens. HS typically presents severe anemia, jaundice, hemoglobinuria, and hemodynamic instability. Diagnostic markers include elevated bilirubin and lactate dehydrogenase levels alongside a reduced reticulocyte count. The management of HS is primarily empirical, with no clinical trials to support standardized treatment protocols. First-line treatments involve steroids and intravenous immunoglobulins (IVIG), which modulate immune responses and mitigate hemolysis. Refractory cases may require additional agents such as rituximab, eculizumab, tocilizumab, and, in some instances, plasma exchange or erythropoietin-stimulating agents. Novel therapeutic approaches, including bortezomib and Hemopure, have shown promise but require further investigation. Current management strategies are empirical, underscoring the need for robust clinical trials to establish effective treatment protocols that ultimately improve outcomes for SCD patients experiencing HS. Full article

Since the approval of Bortezomib (Velcade^®) by the U.S. Food and Drug Administration (FDA) in 2003, boron-containing drugs have successfully entered the global market, spanning therapeutic areas such as anticancer, antibacterial, and antifungal agents. Meanwhile, boron is an essential trace element for plant growth, and boronic acid has been widely used as plant resistance inducers and growth promoters. In 2024, the Fungicide Resistance Action Committee (FRAC) introduced benzoxaboroles as a new category of fungicides, which fully demonstrates the significant application potential of boron-containing compounds (BCCs) in the field of agricultural fungicides. Recently, studies on BCCs in agriculture have emerged continuously. Compared with the systematic reviews in the pharmaceutical field, those focusing on BCCs in agriculture remain absent. This review systematically collates BCCs with reported biological activities from the literature over the past 20 years, from the perspective of boron-containing building blocks. It mainly focuses on the potential of boronic acid derivatization and its activities in agrochemicals. Additionally, it covers the applications of boron-containing building blocks in pharmaceuticals, including their action mechanisms. Full article

Background/Objectives: The treatment of multiple myeloma (MM) remains a challenge, as almost all patients will eventually relapse. Proteasome inhibitors are a cornerstone in the management of MM. Unfortunately, validated biomarkers predicting drug response are largely missing. Therefore, we aimed to identify genes associated with drug resistance or sensitization to proteasome inhibitors. Methods: We performed genome-wide CRISPR-Cas9 knockout (KO) screens in human KMS-28-BM myeloma cells to identify genetic determinants associated with resistance or sensitization to proteasome inhibitors. Results: We show that KO of KLF13 and PSMC4 induces drug resistance, while NUDCD2, OSER1 and HERC1 KO cause drug sensitization. Subsequently, we focused on top sensitization hit, NUDCD2, which acts as a co-chaperone of Hsp90 to regulate the LIS1/dynein complex. RNA sequencing showed downregulation of genes involved in the ERAD pathway and in ER-associated ubiquitin-dependent protein catabolic processes in both untreated and carfilzomib-treated NUDCD2 KO cells, suggesting that NUDCD2 depletion alters protein degradation. Furthermore, bortezomib-treated NUDCD2 KO cells showed a decreased expression of genes that have a function in oxidative phosphorylation and the mitochondrial membrane, such as Carnitine Palmitoyltransferase 1A (CPT1A). CPT1A catalyzes the uptake of long chain fatty acids into mitochondria. Mitochondrial lipid metabolism has recently been reported as a possible therapeutic target for MM drug sensitivity. Conclusions: These results contribute to the search for therapeutic targets that can sensitize MM patients to proteasome inhibitors. Full article

Numerous clinical trials have attempted to improve first-line R-CHOP treatment of diffuse large B-cell lymphoma (DLBCL) through the addition or substitution of drugs. The REMoDL-B trial, testing the addition of bortezomib (RB-CHOP), revealed that ABC and molecular high-grade DLBCL patients benefit from bortezomib. The aim of this study was to achieve a better understanding of the bortezomib response in DLBCL through a functional investigation of clinically identified markers. A retrospective analysis of transcriptional and clinical data from the REMoDL-B trial was conducted to identify genes associated with bortezomib response, identifying CDCA2. DLBCL patients with high expression of CDCA2 had a superior survival outcome when treated with RB-CHOP in comparison to R-CHOP, whereas no difference in outcome was observed for patients with low CDCA2. Moreover, CDCA2 was found to be overexpressed in DLBCL compared to non-malignant tissue, and to have higher levels in GCB and MYC/BCL2 double-expressor patients. Functional in vitro and in vivo studies revealed that knockout of CDCA2 decreased DLBCL cell proliferation and a bortezomib dose–response analysis showed less sensitivity in CDCA2 knockout cells compared to control cells. This study shows that DLBCL patients with high CDCA2 expression benefitted from the addition of bortezomib to R-CHOP and functional studies documented a direct impact of CDCA2 on the bortezomib response in DLBCL cells. Full article

One major public health issue is cancer chemotherapy; despite constant progress in the area, administration of anticancer drugs to patients is often associated with serious side effects. It is therefore imperative to develop vehicles for encapsulation and controlled delivery of such drugs. Anticancer drugs include small peptide drugs, such as Bortezomib (BTZ). Self-assembling peptides have been recently reported as promising drug delivery agents. The research reported here proposes the encapsulation of BTZ into peptide hydrogels formed by the self-assembling FmocFF dipeptide as delivery vehicle. We selected FmocFF as an encapsulation vehicle based on our previous simulation study on the complexation propensity of Bortezomib (BTZ) with various peptide gelators. Herein we undertook additional computational studies that highlight the benefits of FmocFF as a potential effective nanocarrier for BTZ combined with experiments of encapsulation and evaluation of BTZ release. Based on these computational and experimental results, we propose the Fmoc-FF dipeptide hydrogel as a promising matrix for the controlled delivery of BTZ. Full article

Conditional transgenic systems and multi-copy target transgenes were used to produce transient fluorescent protein expression in adult Drosophila melanogaster, with the goal of developing an in vivo assay of protein turnover. Free-moving flies were assayed at multiple time points using video, and decay in fluorescence was used to calculate protein half-life. Additional experiments involved image capture of anesthetized flies. The half-life of eGFP was increased by the proteasome inhibitor bortezomib, both in vivo and in vitro, indicating proteasomal degradation of eGFP. The accumulation of eGFP in vivo was decreased by the protein synthesis inhibitor cycloheximide, without affecting half-life. The half-lives of several fluorescent proteins were determined, using both tissue-general and tissue-specific expression, in flies of both sexes and varying ages. Typical half-life values varied by fluorescent protein. DsRED showed a greater half-life than eGFP, and little if any degradation was detected for mCherry. Half-life also varied by tissue, with greater eGFP half-life observed in muscle relative to other tissues. Increased half-life with age was detected for DsRED but not for eGFP. Limited effects were observed for sex and female mating status. Taken together, the data indicate the in vivo assays are promising tools for the study of protein degradation regulated by protein sequence, subcellular compartment, tissue and small molecules. Full article

The rapid emergence of resistance limits the application of proteasome inhibitors against solid tumors, despite their effectiveness in the treatment of hematological malignancies. Resistant phenotypes are complex and multifaceted, and, thus, the mechanisms involved have not been adequately described. In this study, a Bortezomib-resistant prostate cancer cell line is created by using the PC-3 cell as a prostate carcinoma model of high metastatic potential. The main biochemical differences and adaptations exhibited by the resistant cells revolve around apoptosis evasion, autophagy induction (functioning as a ubiquitin-proteasome system substitute), expression of epithelial-to-mesenchymal transition markers, and increased aggressiveness. Broad-spectrum signaling pathway analyses also reveal an upregulation and activation of Nf-κB, STAT3, cJun, and Elk1 transcription factors in the resistant cells. Additionally, intracellular reactive oxygen species assays reveal a downregulation in resistant cells, which is theorized to be a consequence of metabolic changes, increased autophagic flux, and antioxidative enzyme action. These findings expand our understanding of proteasome inhibitor resistance and highlight key kinases and transcription factors as novel potential therapeutic targets. Effective inhibition of resistance-specific pathways could re-sensitize the cells to proteasome inhibitors, thus surpassing current therapeutic limitations. Full article

Treatment for relapsed/refractory multiple myeloma (RRMM) is complex, with several classes of drugs that can be combined into doublet, triplet, or quadruplet regimens. Real-world studies can help to determine the optimal treatment sequences and dosing through observed usage of drugs outside of clinical trials. Previous clinical trials have demonstrated high rates of durable responses in the treatment of patients with triple-class-exposed RRMM with regimens containing selinexor, a first-in-class, orally available selective exportin 1 inhibitor. This study analyzed real-world treatment patterns and survival outcomes using a nationwide electronic health record-derived, deidentified database of patients with RRMM treated with an eligible selinexor-containing, triplet-based regimen, including combinations with dexamethasone and pomalidomide, bortezomib, carfilzomib, or daratumumab. Patients had a real-world overall survival (rwOS) of 14.7 months (95% CI: 10.6, 20.9) and a derived progression-free survival (dPFS) of 4.7 months (95% CI: 3.4, 6.7). Patients with previous exposure to anti-CD38 monoclonal antibodies (mAbs) in the most recent regimen prior to the selinexor treatment had numerically higher survival outcomes (rwOS, 20.9; dPFS, 8.7 months). These data suggest that, in the real-world setting, the use of selinexor triplet regimens is effective in patients with RRMM, especially those with prior exposure to an anti-CD38 mAb in the immediate prior line of therapy. Full article

The emergence of multidrug-resistant and extensively drug-resistant Mycobacterium tuberculosis strains poses serious challenges to global tuberculosis control, highlighting the urgent need to elucidate the mechanisms underlying multidrug resistance. In this study, we screened for spontaneous bortezomib (BTZ)-resistant Mycobacterium smegmatis (Msm) mutants and identified a strain, Msm-R1-2, exhibiting 16- and 64-fold increases in minimum inhibitory concentrations (MICs) to BTZ and linezolid (LZD), respectively, compared to the parental strain. Whole-genome sequencing revealed resistance-associated mutations in two functionally distinct genes: MSMEG_1380, encoding a transcriptional regulator involved in efflux pump expression, and MSMEG_0965, encoding a porin protein. CRISPR-Cpf1-assisted gene knockout and editing experiments confirmed that single mutations in either MSMEG_1380 or MSMEG_0965 caused low-level resistance (4-fold MIC increase) to BTZ and LZD, while dual mutations conferred resistance levels comparable to Msm-R1-2, with 16- and 64-fold increases in MICs for BTZ and LZD, respectively. An ethidium bromide accumulation assay demonstrated that mutations in MSMEG_0965 reduce cell wall permeability, contributing to multidrug resistance. Furthermore, quantitative real-time PCR showed that mutations in MSMEG_1380 upregulate the mmpS5-mmpL5 efflux system. Together, these dual mechanisms function synergistically: restricted drug entry combined with enhanced drug efflux confers robust multidrug resistance. These findings provide novel insights into the evolutionary mechanisms of resistance in mycobacteria. Full article

The Lon protease homolog 1 (LONP1) is an ATP-dependent mitochondrial protease essential for maintaining proteostasis, bioenergetics, and cellular homeostasis. LONP1 plays a pivotal role in protein quality control, mitochondrial DNA maintenance, and oxidative phosphorylation system (OXPHOS) regulation, particularly under stress conditions. Dysregulation of LONP1 has been implicated in various pathologies, including cancer, metabolic disorders, and reproductive diseases, positioning it as a promising pharmacological target. This review examines compounds that modulate LONP1 activity, categorizing them into inhibitors and activators. Inhibitors such as CDDO and its derivatives selectively target LONP1, impairing mitochondrial proteolysis, inducing protein aggregation, and promoting apoptosis, particularly in cancer cells. Compounds like Obtusilactone A and proteasome inhibitors (e.g., MG262) demonstrate potent cytotoxicity, further expanding the therapeutic landscape. Conversely, LONP1 activators, including Artemisinin derivatives and 84-B10, restore mitochondrial function and protect against conditions such as polycystic ovary syndrome (PCOS) and acute kidney injury (AKI). Future research should focus on improving the specificity, bioavailability, and pharmacokinetics of these modulators. Advances in structural biology and drug discovery will enable the development of novel LONP1-targeted therapies, addressing diseases driven by mitochondrial dysfunction and proteostasis imbalance. Full article

Pure red cell aplasia (PRCA) following major ABO-mismatched allogeneic hematopoietic stem cell transplantation (HSCT) is a challenging complication, affecting 7–10% of patients and significantly impacts quality of life. Despite half of patients showing a resolution within three–six months after HSCT, PRCA might require treatment. Various therapeutic approaches have been investigated, including erythropoietin, plasmapheresis or immunomodulatory therapies (rituximab, bortezomib, corticosteroids, donor lymphocyte infusion (DLI), or the early tapering of immunosuppressive drugs), and TPO-mimetic agents, though responses have generally remained suboptimal. Recently, daratumumab has emerged as a promising, safe, and effective treatment for PRCA, documented by numerous case reports and series. We present a case of PRCA arising in a patient with mixed chimerism following a sibling HSCT for aplastic anemia (AA). In line with the literature, our findings highlight the effectiveness of daratumumab in PRCA from the first dose, although daratumumab administrations were delayed by the onset of infectious complications. Our case supports the earlier introduction of daratumumab in the treatment strategy of PRCA to avoid patient exposure to ineffective therapies that carry risks of increased immunosuppression and infections. Indeed, in our specific case, the early introduction of daratumumab may interrupt the immune hematologic mechanism underlying PRCA, which, in the context of mixed chimerism, could increase the risk of graft failure. Full article