Research Progress on Mechanism of Bortezomib Resistance in Multiple Myeloma / 中国实验血液学杂志

Multiple myeloma (MM) is a common plasma cell malignancy, accounting for the second largest hematological malignancy. Proteasome inhibitors represented by bortezomib (BTZ) have been the main treatment for patients with newly diagnosed and relapsed or refractory myeloma in nearly two decades. Although BTZ has improved the prognosis of MM patients, MM remains incurable in most patients, mainly because MM cells become resistant to BTZ. This review is to better understand the mechanism of MM resistance to BTZ and explore possible new therapeutic strategies.

Diagnosis and treatment of multiple myeloma in Hunan Province / 中南大学学报(医学版)

OBJECTIVES@#There is less clinical data on multiple myeloma (MM) in China, and the aim of this study was to collect and analyze the clinical data of newly diagnosed multiple myeloma (NDMM) patients in Hunan Province during 1 year, to understand the real clinical features and treatment outcome for Hunan Province patients with MM, and to strengthen the understanding of the standardized diagnosis process and treatment plan of MM.@*METHODS@#The clinical data of 529 patients with NDMM in 12 large-scale general hospitals in Hunan Province from January 1 to December 31, 2019 were collected and analyzed, including baseline data, treatment regimens, duration of treatment, and adverse reactions. The clinical characteristics, treatment, and safety of patients were analyzed by SPSS 21.0.@*RESULTS@#Among the 529 NDMM patients, the age was 33-90 (median 64) years and the male-female ratio was 1.38꞉1. The clinical features ranged from high to low were as follows: Bone pain (77.7%), anemia (66.8%), renal insufficiency (40.6%), hypercalcemia (15.1%). Typing: IgG 46.5%, IgA 24.6%, IgD 2.6%, IgM 0.8%, light chain 15.7%, double clone 3.0%, no secretion 0.6%, absence 6.2%. Staging: Durie-Salmon stage I, II, and III were 4.5%, 10.6%, 77.3%, respectively, and 40 cases (7.6%) missed this data. International Staging System (ISS) stage I, II, and III were 10.4%, 24.4%, and 47.6%, respectively, and 93 cases (17.6%) were missing. Revised International Staging System (R-ISS) stage I, II, and III were 5.5%, 27.0%, 23.1%, respectively, and 235 cases (44.4%) missed this data. Among the 98 NDMM patients in the Third Xiangya Hospital, Central South University, Durie-Salmon (DS) stage missing 2.0%, ISS stage missing 12.3%, and R-ISS stage missing 12.3%.Treatment: Among the 529 patients,475 received treatment, the rate of treatment was 89.8%; 67.4% of the patients were able to complete four courses of chemotherapy at induction phase, 90.3% of the patients received proteasome inhibitor based combination chemotherapy regimen more than once, 67.2% received immunomodulator based regimen more than once, and 59.8% of the patients received proteasome inhibitor and immunomodulator based combination chemotherapy regimen more than once. Curative: Overall response rate (ORR) and high quality response rate (HQR) of the 4-course group were better than those of the 2-course group (ORR: 85% vs 65%, P=0.006; HQR: 68.3% vs 24.0%, P<0.001). The HQR of the standard chemotherapy group was better than that of the non-standard chemotherapy group (65.1% vs 48.2%, P=0.035). Adverse reactions during treatment included hematologic toxicity (17.5%), peripheral neuropathy (24.8%), gastrointestinal adverse events (23.8%), pulmonary infection (25.9%), herpes zoster (4.6%), and venous thrombotic events (1.7%).@*CONCLUSIONS@#In 2019, the missed diagnosis rate of MM patients was high, the medium age of diagnosis was older, and the accuracy of patient diagnosis was not high. There is a great difference among medical centers, especially in the stage and risk stratified, nearly half of NDMM patients are not diagnosed with R-ISS stage; the lack of cytogenetic data needs to be supplemented by follow-up studies. A high proportion of patients with NDMM present with bone pain and anemia.Patients received treatment have higher use of chemotherapy regimens containing proteasome inhibitors and/or immunomodulators, but there is a significant gap among different medical centers, and standardized treatment needs to be strengthened. The safety during chemotherapy is controllable.

Experimental study of proteasome inhibitor MG132 up-regulates Wnt/β-catenin signaling pathway to improve osteoporosis / 中国骨伤

OBJECTIVE@#To explore the mechanism of proteasome inhibitor MG132 in improving osteoporosis.@*METHODS@#Total of 32 female SD rats, weighing 220 to 250 g and 8 weeks old, were selected. They were randomly divided into 4 groups(n=8). Rats of group A and group B were cut off ovaris on both sides to make model of osteoporosis, and then they were given proteasome inhibitors MG132 and dimethyl sufoxide (DMSO) respectively. Group C was a sham group and rats were given MG132. Group D was a normal group and rats were given MG132 too. The rats were killed in batches at 6 and 12 weeks after administration, and the femoral neck tissues were obtained. Relevant data were analyzed, such as pathomorphological observation, micro-CT analysis, detection of 20S proteasome activity in tissues, and expression of Wnt and β-catenin.@*RESULTS@#Morphological observation showed that the trabecular were slightly thinner, reticulated, and occasionally interrupted in group A, while the trabecular were obviously thinner and discontinuous in group B. And the trabecular were intact and arranged reticulated in group C and D. The analysis results of bone mineral density(BMD), bone surface(BS), bone volume/total volume(BV/TV) and trabecular thickness(Tb.Th) showed that group B was worse than other groups in all parameters at different time points(P<0.05), and group A was worse than group C and group D in BS(P<0.05), there was no significant difference in all parameters between group C and group D. RFU value of 20S proteasome in group B was significantly higher than that in other groups(P<0.05). According to the results of Western blot, the gray values of Wnt protein and β-catenin protein in group A were significantly higher than those in other groups (P<0.05).@*CONCLUSION@#MG-132, a ubiquitin proteasome inhibitor, can regulate Wnt/β-catenin signaling pathway by inhibiting the degradation of β-catenin protein, and delaying the occurrence and development of osteoporosis.

Evaluation of potential hepatotoxicity induced by Bortezomib

Bortezomib, an inhibitor of 26S proteasome, is an anti-cancer therapeutic agent used in different cancer types. It leads to the arrest of the cancerous cell cycle by inhibiting angiogenesis and inducing apoptosis. Liver is the vital organ for detoxification and excretion of toxic products. The treatment with chemotherapy is a challenge, drugs are used to destroy cancer cells, but healthy cells can be affected during cancer treatment as well. The main objective of this study was to analyze the histopathological and biochemical effects of bortezomib on liver. Twenty-four female C57BL/6 mice were distributed into 4 groups, bortezomib injected treatment groups (Btz1, Btz2) and saline injected control groups (C1, C2). Bortezomib and saline were treated twice per week for 6 weeks and sacrificed at the end of one day (Btz1, C1) and 4 weeks (Btz2, C2) after the last injection. Liver samples were examined for histopathological analysis and the serum samples processed for biochemical analysis. Tissue samples were fixed, routinely processed, sectioned, and stained with Hematoxylin and Eosin (H&E). Periodic Acid-Schiff (PAS), Sudan Black staining and Masson's trichrome histochemical staining methods were performed to characterize the lesions. Histopathological analysis of the Btz1 and Btz2 groups revealed acute hepatic morphological changes such as hepatocellular swelling (cloudy swelling), necro-inflammatory reaction, and increased mononuclear polyploidy. Based on the negative staining with PAS and Sudan Black staining, hepatocellular swelling was diagnosed as hydropic degeneration. Necro-inflammatory reaction observed in the form of acute hepatitis was composed of mainly mononuclear cell infiltration accompanied by multifocal necrotic foci. Kupffer cell proliferation was observed in parallel with degenerative and necrotic changes. An Increase in hepatocellular mononuclear polyploidy visualized as hepatocytes with a single enlarged nucleus was detected in all liver sections of Btz1 and Btz2 groups. Individual cases of cholestasis (n = 1) and mild hepatic fibrosis (n = 1) were also reported. Significant elevated levels of alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) were detected in bortezomib treated groups. Few clinical cases reported liver injury related to bortezomib used for cancer treatment. However, the liver was not considered as a target for bortezomib treatment. Our data suggesting that bortezomib caused liver damage and induces elevations in serum levels. The reported hepatic lesions including hepatocellular swelling, acute hepatitis and mononuclear polyploidy were mainly mild and moderate in severity. The increase of polyploidy in liver tissue of mice treated with bortezomib in this study was explained as a reaction of the liver facing the drug-induced hepatic damage. The mechanism leading to the hepatotoxicity of bortezomib treatment is not known but the production of a toxic metabolite through its metabolism in the liver can be suggested. Moreover, no recovery was also observed in histopathological and biochemical analyses suggesting that the bortezomib effect is non-reversible four weeks after the drug was withdrawn. Patients should be informed about the possibility of acute drug-induced hepatitis and hepatotoxicity of this chemotherapeutic agent after the treatment.(AU)

Oxidative Stress Modulates the Expression Pattern of Peroxiredoxin-6 in Peripheral Blood Mononuclear Cells of Asthmatic Patients and Bronchial Epithelial Cells

PURPOSE: Reduction-oxidation reaction homeostasis is vital for regulating inflammatory conditions and its dysregulation may affect the pathogenesis of chronic airway inflammatory diseases such as asthma. Peroxiredoxin-6, an important intracellular anti-oxidant molecule, is reported to be highly expressed in the airways and lungs. The aim of this study was to analyze the expression pattern of peroxiredoxin-6 in the peripheral blood mononuclear cells (PBMCs) of asthmatic patients and in bronchial epithelial cells (BECs).METHODS: The expression levels and modifications of peroxiredoxin-6 were evaluated in PBMCs from 22 asthmatic patients. Phosphorylated and acetylated peroxiredoxin-6 in hydrogen peroxide-treated human BECs was detected using immunoprecipitation analysis. The expression level of peroxiredoxin-6 was also investigated in BECs treated with hydrogen peroxide. Cycloheximide and proteasome inhibitors were used to determine whether peroxiredoxin-6 is degraded by proteasomes.RESULTS: Peroxiredoxin-6 expression was significantly reduced in the PBMCs of asthmatic patients compared to control subjects. Distinct modification patterns for peroxiredoxin-6 were observed in the PBMCs of asthmatic patients using 2-dimensional-electrophoresis. The levels of phosphorylated serine and acetylated lysine in peroxiredoxin-6 were significantly increased in the BECs following hydrogen peroxide treatment. The level of peroxiredoxin-6 expression was reduced in hydrogen peroxide-stimulated BECs, presumably due to proteasomes.CONCLUSIONS: The expression of peroxiredoxin-6, which is down-regulated in the immune cells of asthmatic patients and BECs, can be modified by oxidative stress. This phenomenon may have an effect on asthmatic airway inflammation.

New proteasome inhibitors in the treatment of multiple myeloma

Abstract The treatment of patients with relapsed and/or refractory multiple myeloma has improved considerably in the last 15 years, after the introduction of proteasome inhibitors and immunomodulatory drugs. The first clinical trials with new proteasome inhibitors have produced exciting results, particularly those comparing triplet regimens with standard doublet regimens, with a gain in progression-free survival accompanied by an acceptable safety profile and either similar or better health-related quality of life. New proteasome inhibitors hold the potential to fill unmet needs in multiple myeloma management regarding improvement of clinical outcomes, including delayed progression of disease in high-risk patients. This review summarizes the main pharmacological properties and clinical outcomes of these agents, and discusses their potential to change the whole multiple myeloma therapeutic landscape.

Inhibition of the 26S and 20S Proteasomes by the Site-specific Inhibitors

OBJECTIVE: The study was performed to establish the purification processes of both 26S and 20S proteasomes, also to investigate the inhibitory properties and patterns of two different proteasome inhibitors on the isolated proteasomes. METHODS: The 26S and 20S proteasomes were purified respectively using liquid chromatographies and glycerol density gradient fractionation. The inhibitory patterns and kinetics of two different proteasome inhibitors were investigated using purified 26S and 20S proteasomes. RESULTS: The purity of the isolated proteasomes were determined by their biochemical properties and electrophoretic patterns. 3-nitro-4-hydroxy-5-indophenylacetyl-leucyl-leucyl-leucyl-vinylsulfone (Nip-L₃-VS) inhibited exclusively the chymotrypsin-like peptidase activities of the 26S and 20S proteasomes. On the other hand, dansyl-phenylyl-leucyl-boronic acid (DFLB) inhibited chymotrpsin-like, trypsin-like, and caspase-like peptidase activities of both proteasomes with different sensitivity. CONCLUSION: The proposed purification method provides efficient separation and isolation of the 26S and 20S proteasomes. Nip-L₃-VS and DFLB were shown to have different inhibitory effects and kinetics on the peptidase activities of the isolated proteasomes. These studies are suggested to be applied to the researches on proteasome inhibitors as therapeutic reagents for many related diseases.

Effects of a Proteasome Inhibitor on Cardiomyocytes in a Pressure-Overload Hypertrophy Rat Model: An Animal Study

BACKGROUND: The ubiquitin-proteasome system (UPS) is an important pathway of proteolysis in pathologic hypertrophic cardiomyocytes. We hypothesize that MG132, a proteasome inhibitor, might prevent hypertrophic cardiomyopathy (CMP) by blocking the UPS. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and androgen receptor (AR) have been reported to be mediators of CMP and heart failure. This study drew upon pathophysiologic studies and the analysis of NF-κB and AR to assess the cardioprotective effects of MG132 in a left ventricular hypertrophy (LVH) rat model. METHODS: We constructed a transverse aortic constriction (TAC)-induced LVH rat model with 3 groups: sham (TAC-sham, n=10), control (TAC-cont, n=10), and MG132 administration (TAC-MG132, n=10). MG-132 (0.1 mg/kg) was injected for 4 weeks in the TAC-MG132 group. Pathophysiologic evaluations were performed and the expression of AR and NF-κB was measured in the left ventricle. RESULTS: Fibrosis was prevalent in the pathologic examination of the TAC-cont model, and it was reduced in the TAC-MG132 group, although not significantly. Less expression of AR, but not NF-κB, was found in the TAC-MG132 group than in the TAC-cont group (p<0.05). CONCLUSION: MG-132 was found to suppress AR in the TAC-CMP model by blocking the UPS, which reduced fibrosis. However, NF-κB expression levels were not related to UPS function.

Nutlin-3 enhances the bortezomib sensitivity of p53-defective cancer cells by inducing paraptosis

The proteasome inhibitor, bortezomib, is ineffective against many solid tumors. Nutlin-3 is a potent antagonist of human homolog of murine double minute 2/p53 interaction exhibiting promising therapeutic anti-cancer activity. In this study, we show that treatment of various p53-defective bortezomib-resistant solid tumor cells with bortezomib plus nutlin-3 induces paraptosis, which is a cell death mode accompanied by dilation of the endoplasmic reticulum (ER) and mitochondria. Bortezomib alone did not markedly alter cellular morphology, and nutlin-3 alone induced only a transient mitochondrial dilation. However, bortezomib/nutlin-3 co-treatment triggered the progressive fusion of swollen ER and the formation of megamitochondria, leading to cell death. Mechanistically, proteasomal-impairment-induced ER stress, CHOP upregulation and disruption of Ca²⁺ homeostasis were found to be critically involved in the bortezomib/nutlin-3-induced dilation of the ER. Our results further suggest that mitochondrial unfolded protein stress may play an important role in the mitochondrial dilation observed during bortezomib/nutlin-3-induced cell death. Collectively, these findings suggest that bortezomib/nutlin-3 perturbs proteostasis, triggering ER/mitochondria stress and irrecoverable impairments in their structure and function, ultimately leading to paraptotic cell death.

Effect of Bortezomib on Angiotensin Ⅱ-induced Abdominal Aortic Aneurysm in ApoEMice / 中国医学科学院学报

Objective To investigate the role of proteasome inhibitor bortezomib (BTZ) in inflammatory response in abdominal aortic aneurysm (AAA) formation induced by angiotensin Ⅱ (Ang Ⅱ). Methods Ang Ⅱ-induced ApoEmice AAA models were established. Forty male ApoEmice (8-10-week-old) were randomly and equally divided into four groups:Sham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group.HE staining,immunohistochemical staining,and flow cytometry were used to analyze the inflammatory response. Real-time quantitative polymerase chain reaction (qPCR) was used to analyze the mRNA expression of intercellular cell adhesion molecule-1 (ICAM-1). Western blotting was used to analyze the activation of nuclear factor κB signaling (NF-κB). Results The mean maximum suprarenal aortic diameter (Dmax) of Sham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group were (1.00±0.01),(0.99±0.01),(1.50±0.13),and (1.20±0.04)mm,respectively (F=8.959,P=0.000). The Dmax of Ang Ⅱ group was significantly larger than those of Sham group (P=0.000) and Ang Ⅱ+BTZ group (P=0.015). The incidence of AAA in Ang Ⅱ group,Ang Ⅱ+BTZ group,and Sham group were 60%,17%,and 0,respectively. HE staining revealed that the abdominal aortic wall thickening was more severe in Ang Ⅱ group than in Sham group and Ang Ⅱ+BTZ group,similar with the infiltration of inflammatory cells. Immunohistochemical staining demonstrated that the CD3T lymphocyte count was significantly higher in Ang Ⅱ group than in Sham group (107.9±15.9 vs. 0,P=0.000) and Ang Ⅱ+BTZ group (107.9±15.9 vs. 0.8±0.5,P=0.000). Flow cytometry also demonstrated that the proportion of the CD3T lymphocytes of the Ang Ⅱ group [(13.50±0.69)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(10.40±0.78)%] at week 1 (t=3.009,P=0.040),and the proportion of the CD3T lymphocytes of the Ang Ⅱ group [(22.70±0.93)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(15.10±0.97)%] at week 4 (t=5.654,P=0.005). The qPCR analysis showed that the mRNA expression of ICAM-1 was significantly up-regulated in Ang Ⅱ group than in Sham group (1.93±0.54 vs. 1.00±0.15,P=0.011) and Ang Ⅱ+BTZ group (1.93±0.54 vs. 0.83±0.08,P=0.009). Western blot analysis showed a lower phosphorylation level of inhibitor of NF-κB in the Ang Ⅱ group compared with the Sham group or Ang Ⅱ+BTZ group,accompanied with an increased phosphorylation level of p65. Conclusion Proteasome inhibitor BTZ can attenuate AAA formation partially by regulating T lymphocytes infiltration through regulating the mRNA expression of ICAM-1 regulated by the activation of NF-κB signaling pathway.

Optimal maintenance and consolidation therapy for multiple myeloma in actual clinical practice

Multiple myeloma is an incurable malignant plasma cell-originating cancer. Although its treatment outcomes have improved with the use of glucocorticoids, alkylating drugs, and novel agents, including proteasome inhibitors (bortezomib and carfilzomib) and immunomodulatory drugs (thalidomide, lenalidomide, and pomalidomide), relapse remains a serious problem. Strategies to improve outcomes following autologous stem cell transplantation and frontline treatments in non-transplant patients include consolidation to intensify therapy and improve the depth of response and maintenance therapy to achieve long-term disease control. Many clinical trials have reported increased progression-free and overall survival rates after consolidation and maintenance therapy. The role of consolidation/maintenance therapy has been assessed in patients eligible and ineligible for transplantation and is a valuable option in clinical trial settings. However, the decision to use consolidation and/or maintenance therapy needs to be guided by the individual patient situation in actual clinical practice. This review analyzes the currently available evidence from several reported clinical trials to determine the optimal consolidation and maintenance therapy in clinical practice.

Two Cases of Bortezomib-induced Drug Eruption Presenting as Multiple Plaques on the Trunk / 대한피부과학회지

Bortezomib (Velcade(R)) is proteasome inhibitor that is used as a first-line therapy for multiple myeloma. It can cause gastrointestinal, hematologic, and neuromuscular side effects, and a cutaneous reaction is one of its common adverse reactions. To date, several bortezomib-induced cutaneous adverse reactions have been reported, including folliculitis-like rash, pruriginous rash, purpuric rash, mouth swelling, stomatitis-mucositis, edema in the lower limbs, telogen effluvium, and vasculitis. In the Korean literature, only one case of vasculitis has been reported earlier. Two patients have presented with multiple plaques on the trunk at our clinic. The lesions developed several days after bortezomib chemotherapy, and disappeared spontaneously in about 1 week. Herein, we report bortezomib-induced drug eruption presenting as multiple plaques on the trunk with a review of the relevant literature.

Inhibitory Effect of Apocynin on Proteasome Inhibition-Induced Apoptosis in Differentiated PC12 Cells

BACKGROUND: The dysfunction of the proteasome system has been implicated in neuronal degeneration. Apocynin, a specific inhibitor for nicotinamide adenine dinucleotide phosphate oxidase, has anti-inflammatory and anti-oxidant effects. However, the effect of apocynin on the neuronal cell death induced by proteasome inhibition has not been studied. METHODS: Using differentiated PC12 cells, in the respect of cell death process the suppressive effect of apocynin on the proteasome inhibition-mediated apoptosis was examined. RESULTS: The proteasome inhibitors MG132 and MG115 induced a decrease in Bid and Bcl-2 protein levels, an increase in Bax and p53 levels, mitochondrial depolarization, efflux of cytochrome c into cytosol and increase in caspases (-8, -9 and -3) activities. Treatment with apocynin attenuated the proteasome inhibitor-induced changes in the apoptosis-related protein levels, formation of reactive oxygen species, glutathione (GSH) depletion and cell death. CONCLUSIONS: Apocynin may attenuate the proteasome inhibitor-mediated apoptosis in differentiated PC12 cells by inhibiting the activation of the mitochondria-mediated pathway and the caspase-8- and Bid-dependent pathways. The preventive effect of apocynin appears to be attributed to inhibition of the production of reactive oxygen species and the depletion of cellular GSH contents.

HIF-1alpha Upregulation due to Depletion of the Free Ubiquitin Pool

Hypoxia-inducible factor 1alpha (HIF-1alpha), which transactivates a variety of hypoxia-induced genes, is rapidly degraded under nomoxia through the hydroxylation-ubiquitination-proteasome pathway. In this study, we addressed how HIF-1alpha is stabilized by proteasome inhibitors. The ubiquitin pool was rapidly reduced after proteasome inhibition, followed by the accumulation of non-ubiquitinated HIF-1alpha. The poly-ubiquitination of HIF-1alpha was resumed by restoration of free ubiquitin, which suggests that the HIF-1alpha stabilization under proteasome inhibition is attributed to depletion of the free ubiquitin pool. Ni2+ and Zn2+ also stabilized HIF-1alpha with depletion of the free ubiquitin pool and these effects of metal ions were attenuated by restoration of free ubiquitin. Ni2+ and Zn2+ may disturb the recycling of free ubiquitin, as MG132 does. Based on these results, the state of the ubiquitin pool seems to be another critical factor determining the cellular level of HIF-1alpha.

Novel Agents for Treatment of Multiple Myeloma / 대한내과학회지

Multiple myeloma (MM) is a neoplasm of clonal plasma cells that closely interacts with the bone marrow (BM) microenvironment. The overall survival of patients with MM has improved dramatically in the last 20 years, due primarily to the development of autologous stem cell transplantation and novel drugs, including a proteasome inhibitor (bortezomib) and immunomodulatory agents (thalidomide and lenalidomide), as well as advances in supportive care. However, this disease remains classified as an incurable hematological malignancy. Understanding the intracellular mechanisms and the interactions between plasma cells and the BM microenvironment has accelerated development of second- and third-generations of "old novel" agents or new agents with novel targeted mechanisms of action, such as monoclonal antibodies, cell cycle-specific drugs, and deacetylase inhibitors. Among them, carfilzomib and pomalidomide have been approved for treating patients with relapsed/refractory MM. Results of ongoing preclinical and clinical trials of novel agents provide hope for continuous improvements and a cure for MM in the near future.

A Case of Acute Pancreatitis Caused by Bortezomib in a Patient with Multiple Myeloma / 대한췌담도학회지

Bortezomib is a proteasome inhibitor used for the treatment of patients with multiple myeloma. Recently, several case reports about acute pancreatitis caused by Bortezomib were published in the international literature. But Bortezomib induced pancreatitis case was not reported in Korea. Herein, we report a case of acute pancreatitis caused by Bortezomib therapy in a 76-year-old female with multiple myeloma. On three months after the first administration of Bortezomib, the patient visited the hospital with symptoms of acute pancreatitis. The common etiological factors for acute pancreatitis were all excluded. Then the patient was diagnosed as Bortezomib-induced pancreatitis. After cessation of Bortezomib, she showed clinical and laboratory improvement.

The Effect of Bortezomib on Expression of Inflammatory Cytokines and Survival in a Murine Sepsis Model Induced by Cecal Ligation and Puncture

PURPOSE: Although the proteasome inhibitor known as bortezomib can modulate the inflammatory process through the nuclear factor-kappa B signaling pathway, the immunomodulatory effect of pre-incubated bortezomib has not been fully evaluated for inflammation by infectious agents. Therefore, we evaluated the effect of bortezomib on the expression of inflammatory cytokines and mediators in macrophage cell lines and on survival in a murine peritonitis sepsis model. MATERIALS AND METHODS: Bortezomib was applied 1 hr before lipopolysaccharide (LPS) stimulation in RAW 264.7 cells. The cecal ligation and puncture (CLP) experiments were performed in C57BL/6J mice. RESULTS: Pre-incubation with bortezomib (25 nM or 50 nM) prior to LPS (50 ng/mL or 100 ng/mL) stimulation significantly recovered the number of viable RAW 264.7 cells compared to those samples without pre-incubation. Bortezomib decreased various inflammatory cytokines as well as nitric oxide production in LPS-stimulated cells. The 7-day survival rate in mice that had received bortezomib at 0.01 mg/kg concentration 1 hr prior to CLP was significantly higher than in the mice that had only received a normal saline solution of 1 mL 1 hr prior to CLP. In addition, the administration of bortezomib at 0.01 mg/kg concentration 1 hr before CLP resulted in a significant decrease in inflammation of the lung parenchyma. Collectively, pretreatment with bortezomib showed an increase in the survival rate and changes in the levels of inflammatory mediators. CONCLUSION: These results support the possibility of pretreatment with bortezomib as a new therapeutic target for the treatment of overwhelming inflammation, which is a characteristic of severe sepsis.

Bis is Induced by Oxidative Stress via Activation of HSF1

The Bis protein is known to be involved in a variety of cellular processes including apoptosis, migration, autophagy as well as protein quality control. Bis expression is induced in response to a number of types of stress, such as heat shock or a proteasome inhibitor via the activation of heat shock factor (HSF)1. We report herein that Bis expression is increased at the transcriptional level in HK-2 kidney tubular cells and A172 glioma cells by exposure to oxidative stress such as H2O2 treatment and oxygen-glucose deprivation, respectively. The pretreatment of HK-2 cells with N-acetyl cysteine, suppressed Bis induction. Furthermore, HSF1 silencing attenuated Bis expression that was induced by H2O2, accompaniedby increase in reactive oxygen species (ROS) accumulation. Using a series of deletion constructs of the bis gene promoter, two putative heat shock elements located in the proximal region of the bis gene promoter were found to be essential for the constitutive expression is as well as the inducible expression of Bis. Taken together, our results indicate that oxidative stress induces Bis expression at the transcriptional levels via activation of HSF1, which might confer an expansion of antioxidant capacity against pro-oxidant milieu. However, the possible role of the other cis-element in the induction of Bis remains to be determined.

Treatment of Refractory Antibody-mediated Rejection with Bortezomib in a Kidney Transplant Recipient: A Case Report / 대한이식학회지

Antibody-mediated rejection (ABMR) is associated with poor renal allograft survival. It shows poor response to conventional treatment with plasmapheresis, rituximab, and intravenous immunoglobulin. Bortezomib, a proteasome inhibitor used for treatment of multiple myeloma, has recently been reported as a treatment alternative for recipient desensitization and ABMR. A 58-year-old man was diagnosed with mixed-type ABMR with donor specific antibodies and acute T cell-mediated rejection early after kidney transplantation. Conventional therapy was administered, including antithymocyte globulin, plasmapheresis, and rituximab; however, his condition was found to be refractory to these antihumoral therapies. Following administration of bortezomib, his serum creatinine level returned to baseline with stable graft function. His serum creatinine level remains stable at 1.3 mg/dL at 10 months posttransplantation. Bortezomib is effective for treatment of refractory ABMR following kidney transplantation.