Polyarteritis nodosa diagnosed in a young male after COVID-19 vaccine: A case report.

In response to the coronavirus disease 2019 pandemic, the coronavirus disease 2019 vaccine was rapidly developed and the effectiveness of the vaccine has been established. However, various adverse effects have been reported, including the development of autoimmune diseases. We report a case of new-onset polyarteritis nodosa in a 32-year-old male following the coronavirus disease 2019 vaccination. The patient developed limb pain, fever, pulmonary embolism, multiple subcutaneous nodules, and haematomas. Skin biopsy revealed necrotising inflammation accompanied by fibrinoid necrosis and high inflammatory cell infiltration in the walls of medium to small arteries. The symptoms resolved following corticosteroid treatment. Although it is difficult to prove a relationship between the vaccine and polyarteritis nodosa, similar cases have been reported and further reports and analyses are therefore necessary.

Expert perspectives on pathological findings in vasculitis.

Pathological findings are important in the diagnosis of vasculitis. However, due to the rarity of the disease, standard textbooks usually devote only a few pages to this topic, and this makes it difficult for clinicians not specializing in vasculitis to fully understand the pathological findings in vasculitis. To address the paucity of information, we present representative pathological findings in vasculitis classified in the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (CHCC2012). The CHCC2012 classifies 26 vasculitides into seven categories: (1) large-vessel vasculitis, (2) medium-vessel vasculitis, (3) small-vessel vasculitis, including antineutrophil cytoplasmic antibody-associated vasculitis and immune complex small-vessel vasculitis, (4) variable-vessel vasculitis, (5) single-organ vasculitis, (6) vasculitis associated with systemic disease, and (7) vasculitis associated with probable aetiology. Moreover, representative pathological findings of vasculitis-related diseases and non-inflammatory vasculopathy not mentioned in the CHCC2012 are also presented. This will be useful for clinicians to refer to typical pathological findings of vasculitis in daily practice.

BubR1 insufficiency impairs angiogenesis in aging and in experimental critical limb ischemic mice.

OBJECTIVES: Budding uninhibited by benzimidazole-related 1 (BubR1), a cell cycle-related protein, is an essential component of the spindle checkpoint that regulates cell division. Mice in which BubR1 expression is reduced to 10% of the normal level display the phenotypic features of progeria. However, the role of BubR1 in vascular diseases and angiogenesis remains unknown. To investigate the influence of BubR1 on angiogenesis, we generated a low-null-BubR1-expressing (BubR1L/-) mouse strain with reduced BubR1 expression as low as 15% of the normal level without any abnormalities in appearance. METHODS: To elucidate the role of BubR1 in angiogenesis, we used a hind limb ischemia model induced in BubR1L/- mice and age-matched wild-type (WT) littermates. To evaluate the pathologic influence of BubR1 on angiogenesis, we measured the blood flow before and after hind limb ischemia surgery, and the expression of typical angiogenic factors in vivo and in vitro. RESULTS: In WT mice, blood flow in the ischemic left limb gradually recovered to approximately 80%, 14 days after surgery. Conversely, in the BubR1L/- group, blood flow in the left ischemic limb recovered to at most 30% (14 days after surgery, P < .01; immediately after the operation, and 5 and 9 days after surgery, P < .05). In adductor and calf muscles from BubR1L/- mice, regenerated muscle bundles, granulation tissue, and inflammatory cell invasion were more evident than in calf muscles from WT mice at 14 days after surgery. All WT mice at 14 days after surgery had complete limb salvage, but loss of limbs was observed in approximately 70% of BubR1L/- mice (P < .05). The vascular endothelial growth factor protein increase in ischemic hind limb muscles was lower in BubR1L/- mice compared with WT mice (P < .05), and vascular endothelial growth factor levels in human aortic smooth muscle cells treated with BubR1 knockdown siRNA were lower compared with scramble siRNA under hypoxic conditions (P < .01). HIF1α protein levels in the muscles after hind limb ischemia surgery were also significantly lower in BubR1L/- mice compared with WT mice (P < .05). CONCLUSIONS: BubR1 insufficiency impairs angiogenesis and results in limb loss in ischemic hind limbs. BubR1 may be a crucial angiogenic factor and might be beneficial for the treatment of limb ischemia.

Chd2 regulates chromatin for proper gene expression toward differentiation in mouse embryonic stem cells.

Chromatin reorganization is necessary for pluripotent stem cells, including embryonic stem cells (ESCs), to acquire lineage potential. However, it remains unclear how ESCs maintain their characteristic chromatin state for appropriate gene expression upon differentiation. Here, we demonstrate that chromodomain helicase DNA-binding domain 2 (Chd2) is required to maintain the differentiation potential of mouse ESCs. Chd2-depleted ESCs showed suppressed expression of developmentally regulated genes upon differentiation and subsequent differentiation defects without affecting gene expression in the undifferentiated state. Furthermore, chromatin immunoprecipitation followed by sequencing revealed alterations in the nucleosome occupancy of the histone variant H3.3 for developmentally regulated genes in Chd2-depleted ESCs, which in turn led to elevated trimethylation of the histone H3 lysine 27. These results suggest that Chd2 is essential in preventing suppressive chromatin formation for developmentally regulated genes and determines subsequent effects on developmental processes in the undifferentiated state.

BUBR1 Insufficiency in Mice Increases their Sensitivity to Oxidative Stress.

BACKGROUND/AIM: Budding uninhibited by benzimidazole-related 1 (BUBR1) plays an important role in the spindle assembly checkpoint to prevent chromosome missegregation and aneuploidy during mitosis. We previously generated mutant mice that express BUBR1 at only 20% of the normal level (BubR1L/L mice). Here, we examined the effect of low BUBR1 expression on oxidative stress-induced carcinogenesis in mice. MATERIALS AND METHODS: We orally administered either a potassium bromate (KBrO3) solution (2 g/l) or tap water to BubR1L/L and wild-type (BubR1+/+)mice for 16 weeks and examined the subsequent incidence of tumours. RESULTS: KBrO3-treated BubR1L/L mice showed significantly higher mortality than the KBrO3-treated BubR1+/+ and control tap water-treated mice (p=0.0082). Histopathological and immunohistochemical analyses revealed that the spleens of surviving BubR1L/L mice were occupied by non-B-, non-T-cells with high proliferative potential. CONCLUSION: Our results indicate that low BUBR1 expression increases oxidative stress-induced mortality in mice, possibly caused by splenic neoplasms.

BubR1 Insufficiency Impairs Liver Regeneration in Aged Mice after Hepatectomy through Intercalated Disc Abnormality.

A delay in liver regeneration after partial hepatectomy (PHx) leads to acute liver injury, and such delays are frequently observed in aged patients. BubR1 (budding uninhibited by benzimidazole-related 1) controls chromosome mitotic segregation through the spindle assembly checkpoint, and BubR1 down-regulation promotes aging-associated phenotypes. In this study we investigated the effects of BubR1 insufficiency on liver regeneration in mice. Low-BubR1-expressing mutant (BubR1(L/L)) mice had a delayed recovery of the liver weight-to-body weight ratio and increased liver deviation enzyme levels after PHx. Microscopic observation of BubR1(L/L) mouse liver showed an increased number of necrotic hepatocytes and intercalated disc anomalies, resulting in widened inter-hepatocyte and perisinusoidal spaces, smaller hepatocytes and early-stage microvilli atrophy. Up-regulation of desmocollin-1 (DSC1) was observed in wild-type, but not BubR1(L/L), mice after PHx. In addition, knockdown of BubR1 expression caused down-regulation of DSC1 in a human keratinocyte cell line. BubR1 insufficiency results in the impaired liver regeneration through weakened microstructural adaptation against PHx, enhanced transient liver failure and delayed hepatocyte proliferation. Thus, our data suggest that a reduction in BubR1 levels causes failure of liver regeneration through the DSC1 abnormality.

Activation of Nod1 Signaling Induces Fetal Growth Restriction and Death through Fetal and Maternal Vasculopathy.

Intrauterine fetal growth restriction (IUGR) and death (IUFD) are both serious problems in the perinatal medicine. Fetal vasculopathy is currently considered to account for a pathogenic mechanism of IUGR and IUFD. We previously demonstrated that an innate immune receptor, the nucleotide-binding oligomerization domain-1 (Nod1), contributed to the development of vascular inflammations in mice at postnatal stages. However, little is known about the deleterious effects of activated Nod1 signaling on embryonic growth and development. We report that administration of FK565, one of the Nod1 ligands, to pregnant C57BL/6 mice induced IUGR and IUFD. Mass spectrometry analysis revealed that maternally injected FK565 was distributed to the fetal tissues across placenta. In addition, maternal injection of FK565 induced robust increases in the amounts of CCL2, IL-6, and TNF proteins as well as NO in maternal, placental and fetal tissues. Nod1 was highly expressed in fetal vascular tissues, where significantly higher levels of CCL2 and IL-6 mRNAs were induced with maternal injection of FK565 than those in other tissues. Using Nod1-knockout mice, we verified that both maternal and fetal tissues were involved in the development of IUGR and IUFD. Furthermore, FK565 induced upregulation of genes associated with immune response, inflammation, and apoptosis in fetal vascular tissues. Our data thus provided new evidence for the pathogenic role of Nod1 in the development of IUGR and IUFD at the maternal-fetal interface.

Peritoneal Dissemination Requires an Sp1-Dependent CXCR4/CXCL12 Signaling Axis and Extracellular Matrix-Directed Spheroid Formation.

Peritonitis carcinomatosa is an advanced and intractable state of gastrointestinal and ovarian cancer, where mechanistic elucidation might enable the development of more effective therapies. Peritoneal dissemination of this type of malignancy has been generally thought to initiate from "milky spots" of primitive lymphoid tissues in the peritoneal cavity. In this study, we offer evidence challenging this idea, based on the finding that tumor implantation and directional dissemination was not required for the presence of milky spots, but rather SCF/CXCL12-expressing niche-like cells located at the border regions of perivascular adipose tissue. Interestingly, we found that peritoneal cavity lavage fluid, which specifically contains peritoneal collagen type IV and plasma fibronectin, dramatically facilitated spheroid formation of murine and human colon cancer cells. Spheroid formation strongly induced the expression of CXCR4 in an Sp1-dependent manner to promote niche-directed metastasis. Notably, disrupting sphere formation or inhibiting Sp1 activity was sufficient to suppress tumor dissemination and potentiated chemosensitivity to 5-fluorouracil. Our findings illuminate mechanisms of peritoneal cancer dissemination and highlight the Sp1/CXCR4/CXCL12 signaling axis as a rational target for the development of therapeutics to manage this intractable form of malignancy.

Activation of an innate immune receptor, Nod1, accelerates atherogenesis in Apoe-/- mice.

Atherosclerosis is essentially a vascular inflammatory process in the presence of an excess amount of lipid. We have recently reported that oral administration of a nucleotide-binding oligomerization domain (Nod)-1 ligand, FK565, induced vascular inflammation in vivo. No studies, however, have proven the association between Nod1 and atherosclerosis in vivo. To investigate a potential role of NOD1 in atherogenesis, we orally administered FK565 to apolipoprotein E knockout (Apoe(-/-)) mice for 4 wk intermittently and performed quantification of atherosclerotic lesions in aortic roots and aortas, immunohistochemical analyses, and microarray-based gene expression profiling of aortic roots. FK565 administration accelerated the development of atherosclerosis in Apoe(-/-) mice, and the effect was dependent on Nod1 in non-bone marrow origin cells by bone marrow transplantation experiments. Immunohistochemical studies revealed the increases in the accumulation of macrophages and CD3 T cells within the plaques in aortic roots. Gene expression analyses of aortic roots demonstrated a marked upregulation of the Ccl5 gene during early stage of atherogenesis, and the treatment with Ccl5 antagonist significantly inhibited the acceleration of atherosclerosis in FK565-administered Apoe(-/-) mice. Additionally, as compared with Apoe(-/-) mice, Apoe and Nod1 double-knockout mice showed reduced development of atherosclerotic lesions from the early stage as well as their delayed progression and a significant reduction in Ccl5 mRNA levels at 9 wk of age. Data in the present study show that the Nod1 signaling pathway in non-bone marrow-derived cells contributes to the development of atherosclerosis.

BubR1 insufficiency inhibits neointimal hyperplasia through impaired vascular smooth muscle cell proliferation in mice.

OBJECTIVE: BubR1, a cell cycle-related protein, is an essential component of the spindle checkpoint that regulates cell division. Mice with BubR1 expression reduced to 10% of the normal level display a phenotype characterized by progeria; however, the involvement of BubR1 in vascular diseases is still unknown. We generated mice in which BubR1 expression was reduced to 20% (BubR1(L/L) mice) of that in wild-type mice (BubR1(+/+)) to investigate the effects of BubR1 on arterial intimal hyperplasia. APPROACH AND RESULTS: Ten-week-old male BubR1(L/L) and age-matched wild-type littermates (BubR1(+/+)) were used in this study. The left common carotid artery was ligated, and histopathologic examinations were conducted 4 weeks later. Bone marrow transplantation was also performed. Vascular smooth muscle cells (VSMCs) were isolated from the thoracic aorta to examine cell proliferation, migration, and cell cycle progression. Severe neointimal hyperplasia was observed after artery ligation in BubR1(+/+) mice, whereas BubR1(L/L) mice displayed nearly complete inhibition of neointimal hyperplasia. Bone marrow transplantation from all donors did not affect the reconstitution of 3 hematopoietic lineages, and neointimal hyperplasia was still suppressed after bone marrow transplantation from BubR1(+/+) mice to BubR1(L/L) mice. VSMC proliferation was impaired in BubR1(L/L) mice because of delayed entry into the S phase. VSMC migration was unaffected in these BubR1(L/L) mice. p38 mitogen-activated protein kinase-inhibited VSMCs showed low expression of BubR1, and BubR1-inhibited VSMCs showed low expression of p38. CONCLUSIONS: BubR1 may represent a new target molecule for treating pathological states of vascular remodeling, such as restenosis after angioplasty.

Biological characterization and analysis of metastasis-related genes in cell lines derived from the primary lesion and lymph node metastasis of a squamous cell carcinoma arising in the mandibular gingiva.

Controlling metastatic lesions is an important part of improving cancer prognosis, in addition to controlling the primary lesion. There have been numerous histological studies on primary and metastatic lesions, but little basic research has been performed using cell lines from primary and metastatic lesions belonging to the same patient. In this study, we successfully established a cell line derived from lower gingival carcinoma (WK2) as well as a line derived from secondary cervical lymph node metastasis (WK3F) through primary cultures of tissue from a patient with oral squamous cell carcinoma. We then investigated the biological characteristics of the cancer cell lines from these primary and metastatic lesions and analyzed metastasis-related genes. Comparison of the biological characteristics in vitro showed that WK3F had higher cell proliferation ability and shorter cell doubling time than WK2. WK3F also had increased cell migratory ability and higher invasive and self-replication abilities. Heterotransplantation into nude mice resulted in high tumor formation rates in the tongue and high metastasis rates in the cervical lymph nodes. Changes in WK2 and WK3F gene expression were then comprehensively analyzed using microarrays. Genes with increased expression in WK3F compared to WK2 were extracted when the Z-score was ≥2.0 and the ratio was ≥5.0, while genes with reduced expression in WK3F compared to WK2 were extracted when the Z-score was ≤-2.0 and the ratio was ≤0.2; differences were found in 604 genes. From these, MAGEC1 (88.0-fold), MMP-7 (18.6-fold), SNAI1 (6.6-fold), MACC1 (6.2-fold), and HTRA1 (0.012-fold) were selected as metastasis-related candidate genes. The results suggest that these molecules could be important for clarifying the mechanisms that regulate metastasis and provide new therapeutic targets for inhibiting tumor invasion.

Ex vivo generation of highly purified and activated natural killer cells from human peripheral blood.

Adoptive immunotherapy using natural killer (NK) cells has been a promising treatment for intractable malignancies; however, there remain a number of difficulties with respect to the shortage and limited anticancer potency of the effector cells. We here established a simple feeder-free method to generate purified (>90%) and highly activated NK cells from human peripheral blood-derived mononuclear cells (PBMCs). Among the several parameters, we found that CD3 depletion, high-dose interleukin (IL)-2, and use of a specific culture medium were sufficient to obtain highly purified, expanded (∼200-fold) and activated CD3(-)/CD56(+) NK cells from PBMCs, which we designated zenithal-NK (Z-NK) cells. Almost all Z-NK cells expressed the lymphocyte-activated marker CD69 and showed dramatically high expression of activation receptors (i.e., NKG2D), interferon-γ, perforin, and granzyme B. Importantly, only 2 hours of reaction at an effector/target ratio of 1:1 was sufficient to kill almost all K562 cells, and the antitumor activity was also replicated in tumor-bearing mice in vivo. Cytolysis was specific for various tumor cells, but not for normal cells, irrespective of MHC class I expression. These findings strongly indicate that Z-NK cells are purified, expanded, and near-fully activated human NK cells and warrant further investigation in a clinical setting.

Chronic kidney disease is associated with neovascularization and intraplaque hemorrhage in coronary atherosclerosis in elders: results from the Hisayama Study.

There is little information regarding whether patients with chronic kidney disease (CKD) have a high incidence of vulnerable plaques in their coronary arteries. To gain additional evidence on this, we conducted a population-based study by randomly selecting 126 subjects from 844 consecutive autopsies of elderly residents of Hisayama, Japan. We then determined the relationships of CKD with neovascularization and intraplaque hemorrhage in coronary atherosclerosis with the subjects classified into four categories based on their estimated glomerular filtration rate (eGFR). Areas of oxidized low-density lipoprotein (oxLDL) and vascular endothelial growth factor (VEGF) expression, assessed by immunohistochemistry in a total of 375 coronary arteries, increased significantly with decreasing eGFR. A lower eGFR was also associated with increased numbers of newly formed blood vessels. These relationships remained substantially unchanged after adjustment for confounding factors. The multivariate-adjusted odds ratio of the presence of intraplaque hemorrhages was 6.2 (95% confidence interval, 1.1-35.0) in patients with an eGFR <30 ml/min/1.73 m(2) compared with those with an eGFR of ≥ 60 ml/min/1.73 m(2). Thus, elderly patients with CKD have intimal neoangiogenesis and an increased risk of intraplaque hemorrhage in coronary arteries, possibly favored by local accumulation of oxLDL and VEGF.

DVC1-0101 to treat peripheral arterial disease: a Phase I/IIa open-label dose-escalation clinical trial.

We here report the results of a Phase I/IIa open-label four dose-escalation clinical study assessing the safety, tolerability, and possible therapeutic efficacy of a single intramuscular administration of DVC1-0101, a new gene transfer vector based on a nontransmissible recombinant Sendai virus (rSeV) expressing the human fibroblast growth factor-2 (FGF-2) gene (rSeV/dF-hFGF2), in patients with peripheral arterial disease (PAD). Gene transfer was done in 12 limbs of 12 patients with rest pain, and three of them had ischemic ulcer(s). No cardiovascular or other serious adverse events (SAEs) caused by gene transfer were detected in the patients over a 6-month follow-up. No infectious viral particles, as assessed by hemagglutination activity, were detected in any patient during the study. No representative elevation of proinflammatory cytokines or plasma FGF-2 was seen. Significant and continuous improvements in Rutherford category, absolute claudication distance (ACD), and rest pain were observed (P < 0.05 to 0.01). To the best of our knowledge, this is the first clinical trial of the use of a gene transfer vector based on rSeV. The single intramuscular administration of DVC1-0101 to PAD patients was safe and well tolerated, and resulted in significant improvements of limb function. Larger pivotal studies are warranted as a next step.

Endogenous cardiac troponin T modulates Ca(2+)-mediated smooth muscle contraction.

Mechanisms linked to actin filaments have long been thought to cooperate in smooth muscle contraction, although key molecules were unclear. We show evidence that cardiac troponin T (cTnT) substantially contributes to Ca(2+)-mediated contraction in a physiological range of cytosolic Ca(2+) concentration ([Ca(2+)](i)). cTnT was detected in various smooth muscles of the aorta, trachea, gut and urinary bladder, including in humans. Also, cTnT was distributed along with tropomyosin in smooth muscle cells, suggesting that these proteins are ready to cause smooth muscle contraction. In chemically permeabilised smooth muscle of cTnT(+/-) mice in which cTnT reduced to ~50%, the Ca(2+)-force relationship was shifted toward greater [Ca(2+)](i), indicating a sizeable contribution of cTnT to smooth muscle contraction at [Ca(2+)](i) < 1 µM. Furthermore, addition of supplemental TnI and TnC reconstructed a troponin system to enhance contraction. The results indicated that a Tn/Tn-like system on actin-filaments cooperates together with the thick-filament pathway.

Transfection of hypoxia-inducible factor-1 decoy oligodeoxynucleotides suppresses expression of vascular endothelial growth factor in oral squamous cell carcinoma cells.

Vasculature development is thought to be an important aspect in the growth and metastasis of solid tumors. Among the many angiogenic factors produced by tumor cells, vascular endothelial growth factor (VEGF) is considered to play a key role in angiogenic processes. VEGF synthesis is modulated by hypoxia-inducible factor-1 (HIF-1) function within the hypoxic microenvironment of growing cancer tissue. To inhibit HIF-1 activation, oligodeoxynucleotides (ODNs) were synthesized and transferred with either the consensus sequence for HIF-1 binding or a mutated form of this sequence. If we could transfer a large number of ODNs into the cancer cell nucleus, activated HIF-1 might bind to the ODNs, resulting in inhibition of hypoxia-induced VEGF synthesis. We transferred these ODNs into cultured oral squamous cell carcinoma cells (SAS cells) using the hemagglutinating virus of Japan (HVJ)-liposome method. Hypoxia-mediated expression of VEGF by cancer cells was suppressed by transfection of HIF-1 decoy ODNs, but not by mutated HIF-1 decoy ODNs. HIF-1 decoy ODN transfection also inhibited VEGF protein synthesis. These results suggest that transfection with HIF-1 decoy ODNs is effective for regulating tumor growth by reducing VEGF.

Obstruction enhances rho-kinase pathway and diminishes protein kinase C pathway in carbachol-induced calcium sensitization in contraction of α-toxin permeabilized guinea pig detrusor smooth muscle.

AIMS: We investigated the relative important role of rho kinase (ROK) and protein kinase C (PKC) pathways in carbachol (CCh)-induced Ca(2+) sensitization in α-toxin permeabilized Guinea pig detrusor smooth muscle (DSM) following bladder outlet obstruction (BOO). METHODS: Bladder outlet obstruction was created by placement of a silver jeweler's jump rings loosely round the urethro-vesical junction of Guinea pigs. Sham operated Guinea pig underwent a similar protocol without application of the ring and served as control. α-Toxin permeabilized DSM strips from control Guinea pigs and those subjected to 6-8 weeks of BOO were mounted horizontally for isometric force recording in 100 µl relaxing solution on perspex block. The effect of ROK inhibitor (Y-27632) and PKC inhibitor (GF-109203X) on CCh-induced Ca(2+) sensitization was studied during sustained contraction. Permeabilized DSM strips were also stimulated by cumulative increase of Ca(2+) concentration compared to that in control in the presence and in the absence of sensitization-induced PKC activator, phorbol 12,13-dibutyrate. RESULTS: Ca(2+) sensitization-induced by CCh was greater in BOO compared to controls. This muscarinic agonist-induced Ca(2+) sensitization was inhibited by Y-27632 or GF-109203X. The inhibitory effect of Y-27632 (5 µM) was greater while the inhibitory effect of GF-109203X (5 µM) was smaller in BOO compared to that in controls. Phorbol 12,13-dibutyrate (1 µM) markedly increased Ca(2+) sensitivity in controls but not in BOO. CONCLUSIONS: Our findings provide the first evidence that BOO enhances the ROK pathway and diminishes the PKC pathway in CCh-induced Ca(2+) sensitization in contraction of permeabilized Guinea pig DSM and suggest that inhibitors of ROK might potentially relieve bladder dysfunction related to BOO.

BioKnife, a uPA activity-dependent oncolytic Sendai virus, eliminates pleural spread of malignant mesothelioma via simultaneous stimulation of uPA expression.

Malignant pleural mesothelioma (MPM) is highly intractable and readily spreads throughout the surface of the pleural cavity, and these cells have been shown to express urokinase-type plasminogen activator receptor (uPAR). We here examined the potential of our new and powerful recombinant Sendai virus (rSeV), which shows uPAR-specific cell-to-cell fusion activity (rSeV/dMFct14 (uPA2), named "BioKnife"), for tumor cell killing in two independent orthotopic xenograft models of human. Multicycle treatment using BioKnife resulted in the efficient rescue of these models, in association with tumor-specific fusion and apoptosis. Such an effect was also seen on both MSTO-211H and H226 cells in vitro; however, we confirmed that the latter expressed uPAR but not uPA. Of interest, infection with BioKnife strongly facilitated the uPA release from H226 cells, and this effect was completely abolished by use of either pyrrolidine dithiocarbamate (PDTC) or BioKnife expressing the C-terminus-deleted dominant negative inhibitor for retinoic acid-inducible gene-I (RIG-IC), indicating that BioKnife-dependent expression of uPA was mediated by the RIG-I/nuclear factor-κB (NF-κB) axis, detecting RNA viral genome replication. Therefore, these results suggest a proof of concept that the tumor cell-killing mechanism via BioKnife may have significant potential to treat patients with MPM that is characterized by frequent uPAR expression in a clinical setting.