Akihito Uehara

MFG-E8 Drives Melanoma Growth by Stimulating Mesenchymal Stromal Cell–Induced Angiogenesis and M2 Polarization of Tumor-Associated Macrophages

Secretion of the powerful angiogenic factor MFG-E8 by pericytes can bypass the therapeutic effects of anti-VEGF therapy, but the mechanisms by which MFG-E8 acts are not fully understood. In this study, we investigated how this factor acts to promote the growth of melanomas that express it. We found that mouse bone marrow-derived mesenchymal stromal cells (MSC) expressed a substantial amount of MFG-E8. To assess its expression from this cell type, we implanted melanoma cells and MSC derived from wild type (WT) or MFG-E8 deficient [knockout (KO)] into mice and monitored tumor growth. Tumor growth and M2 macrophages were each attenuated in subjects coimplanted with KO-MSC compared with WT-MSC. In both xenograft tumors and clinical specimens of melanoma, we found that MFG-E8 expression was heightened near blood vessels where MSC could be found. Through in vitro assays, we confirmed that WT-MSC-conditioned medium was more potent at inducing M2 macrophage polarization, compared with KO-MSC-conditioned medium. VEGF and ET-1 expression in KO-MSC was significantly lower than in WT-MSC, correlating in vivo with reduced tumor growth and numbers of pericytes and M2 macrophages within tumors. Overall, our results suggested that MFG-E8 acts at two levels, by increasing VEGF and ET-1 expression in MSC and by enhancing M2 polarization of macrophages, to increase tumor angiogenesis. Cancer Res; 76(14); 4283-92. ©2016 AACR.

Mechanistic insight into the norepinephrine-induced fibrosis in systemic sclerosis

Raynauds phenomenon is frequently observed in systemic sclerosis (SSc) patients, and cold- or stress-induced norepinephrine (NE) has been speculated to be associated with vasoconstriction. Objective was to elucidate the role of NE in fibrosis in SSc. IL-6 is a potent stimulator of collagen production in fibroblasts. NE enhanced IL-6 production and proliferation more significantly in SSc fibroblasts than in normal fibroblasts. Furthermore, the production of IL-6 and phosphorylation of p38 in SSc fibroblasts was enhanced by adrenergic receptor (AR)β agonist, isoproterenol, but not ARα agonist, oxymetazoline. ARβ blocker, propranolol, inhibited NE-induced IL-6 production and phosphorylation of p38 in SSc fibroblasts. NE-induced IL-6 was significantly inhibited by p38 inhibitor, SB203580, suggesting that NE-induced phosphorylation of p38 via ARβ enhances IL-6 production in SSc fibroblasts. NE-induced phosphorylation of ERK1/2 via ARα inhibited IL-6 production in SSc fibroblasts. Combined treatment with NE and endothelin-1 resulted in an additive increase in IL-6 production in SSc fibroblasts. NE-induced IL-6/IL-6 receptor trans-signaling increased the production of collagen type I in SSc fibroblasts, and both propranolol and SB203580 inhibited NE-induced collagen production. These results suggest that cold exposure and/or emotional stress-induced NE might contribute to the skin fibrosis via potentiation of IL-6 production from fibroblasts in SSc.

Inhibitory Regulation of Skin Fibrosis in Systemic Sclerosis by Apelin/APJ Signaling

Apelin/APJ signaling has been determined to regulate cardiac and arterial fibrosis and to be involved in the pathogenesis of pulmonary arterial hypertension. Our objective was to elucidate the role of apelin in skin fibrosis in systemic sclerosis (SSc).

Protective effect of mesenchymal stem cells on the pressure ulcer formation by the regulation of oxidative and endoplasmic reticulum stress

Cutaneous ischemia-reperfusion (I/R) injury is associated with the early pathogenesis of cutaneous pressure ulcers (PUs). The objective of this study was to investigate the effect of mesenchymal stem cells (MSCs) injection on the formation of PUs after I/R injury and determine the underlying mechanisms. We found that the subcutaneous injection of MSCs into areas of I/R injured skin significantly suppressed the formation of PUs. I/R-induced vascular damage, hypoxia, oxidative DNA damage, and apoptosis were decreased by MSCs injection. Oxidative stress signals detected after I/R in OKD48 (Keap1-dependent oxidative stress detector, No-48-luciferase) mice were decreased by the injection of MSCs. In cultured fibroblasts, MSCs-conditioned medium significantly inhibited oxidant-induced reactive oxygen species (ROS) generation and apoptosis. Furthermore, endoplasmic reticulum (ER) stress signals detected after I/R in ERAI (ER stress-activated indicator) mice were also decreased by the injection of MSCs. These results suggest that the injection of MSCs might protect against the development of PUs after cutaneous I/R injury by reducing vascular damage, oxidative cellular damage, oxidative stress, ER stress, and apoptosis.

Case of angioedema and urticaria induced by lenalidomide

between 1998 and 2009. We cannot exclude the possibility that dacarbazine or DAV therapy contributed mainly to the occurrence of t-MDS in the present case. Pathomechanisms of t-MDS by alkylating agents and also cisplatin, an alkylating-like agent, are thought to be due to DNA damage to hematopoietic stem cells, resulting in mismatch repair deficiency and mutator phenotypes that accelerate the occurrence of t-MDS. The present case suggests that we should pay attention to the risk of t-MDS after chemotherapy for MM, especially after combination chemotherapy consisting of alkylating agents and platinum, such as the DAC therapy.

Pilomatricoma with bullous-like/anetodermic appearance: Possibly associated with matrix metalloproteinases

Figure 1. (a) Pilomatricoma with bullous-like/anetodermic appearance in the left axilla. (b) Few elastic fibers in the superficial dermis (elastica van Gieson [EVG], original magnification 9100). (c) CD68-positive macrophages in the superficial dermis (9400). (d) Matrix metalloproteinase (MMP)-9 was stained in fibroblasts and infiltrating inflammatory cells (9400). (e) MMP-12 was stained in infiltrating cells in the superficial dermis (9400). (f) Pilomatricoma with ordinary appearance. Subcutaneous tumor on the right eyebrow. (g) Many elastic fibers in the superficial dermis (EVG, 9100). (h) No CD68-positive macrophages in the dermis (9400). Neither (i) MMP-9 nor (j) MMP-12 was stained in the dermis (9400). (k) The results of histopathological analysis on pilomatricoma with bullous-like/anetodermic appearance and with ordinary appearance (9). –, undetectable; +, weak positivity; ++, moderate positivity; +++, strong positivity.

Successful treatment with i.v. immunoglobulin for localized cutaneous immunoglobulin light chain kappa-positive amyloidosis associated with dermatomyositis

Dear Editor, A 50-year-old Japanese woman had a 21-year history of dermatomyositis, and had been treated and followed up in our department. She complained of skin changes 3 months before arrival. Physical examination revealed dark reddish and brown erythema and papules on the forehead, temple, eyelids, cheeks, nose, upper lip, neck and upper back (Fig. 1a–c) and Gottron’s papules on her hands. She had muscle weakness and dysphagia. Routine blood tests were normal, including creatine kinase (49 IU/L; normal, 45–163) and aldolase (5.6 IU/ L; normal, 2.1–6.1). Anti-transcriptional intermediary factor (TIF) 1-c antibody was positive; however, anti-Jo-1, anti-aminoacyltransfer RNA synthetase and anti-melanoma differentiationassociated gene 5 antibodies were negative. No interstitial lung disease and internal malignancy were detected by comprehensive examinations. Histopathological examination of the left temple showed liquefaction degeneration, infiltration of many lymphocytes and some plasma cells in the dermis, and thick deposits of an eosinophilic, homogeneous substance in the papillary dermis (Fig. 1d), which were positive for direct fast scarlet staining (Fig. 1e). Immunohistochemical staining of the amyloid-deposited lesion resulted in positive staining with anti-immunoglobulin light chain kappa (Fig. 1f) and anti-serum amyloid P antibodies, but negative staining with anti-keratin (Fig. 1g) and anti-transthyretin antibodies. Multiple myeloma was excluded by normal levels of urinary Bence Jones protein and the ratio of j/k immunoglobulin free light chain (1.07; normal, 0.31–1.56), no serum M-protein, and no submucosal amyloid deposits by stomach, duodenum, colon and rectum biopsy. Finally, diagnosis was established of secondary localized cutaneous amyloidosis associated with dermatomyositis.

Botulinum toxin B suppresses the pressure ulcer formation in cutaneous ischemia-reperfusion injury mouse model: Possible regulation of oxidative and endoplasmic reticulum stress

BACKGROUND We previously identified that botulinum toxin A (BTX-A) suppressed pressure ulcer (PU) formation after cutaneous ischemia-reperfusion (I/R) injury; however, regulation of cutaneous I/R-induced oxidative and endoplasmic reticulum (ER) stress by BTX-B was not investigated. Additionally, the efficacy of BTX-B injection has never been examined. OBJECTIVE Objective was to assess the effects of BTX-B on the formation of PU by cutaneous I/R injury, and the regulation of oxidative and ER stress in I/R injury by BTX-B. METHODS BTX-B was subcutaneously injected into I/R area, and wound size, vascular damage, hypoxic area, and apoptotic cells in I/R area were analyzed. We evaluated the extent of oxidative and ER stress in I/R area by using OKD48 mice and ERAI mice, respectively, which enabled evaluating oxidative and ER stress through bioluminescence detection. RESULTS BTX-B injection significantly suppressed the formation of PU by cutaneous I/R injury. Cutaneous I/R-induced vascular damage, hypoxic area, and number of oxidative-damaged cells and apoptotic cells were suppressed by BTX-B injection. BTX-B administration significantly inhibited I/R-induced oxidative stress signal in OKD48 mice. BTX-B reduced the I/R-induced oxidative stress-associated factors. BTX-B significantly inhibited the oxidant-induced reactive oxygen species and apoptosis of endothelial cells and fibroblasts. BTX-B significantly inhibited I/R-induced ER stress signal in ERAI mice. Cutaneous I/R injury-induced ER stress-response factors and GRP78/BiP and CHOP-positive cells in I/R area were significantly decreased by BTX-B injection. CONCLUSION BTX-B injection might have protective effects against PU formation after cutaneous I/R injury by reducing vascular damage, hypoxia-induced oxidative and ER stress, and apoptosis.

Suppressive regulation of MFG-E8 on latent-TGF-β-induced fibrosis via binding to integrin αV: The significance in the pathogenesis of fibrosis in systemic sclerosis

Several studies have demonstrated that the secreted glycoprotein and integrin ligand milk fat globule–associated protein with epidermal growth factor– and factor VIII–like domains (MFG‐E8) negatively regulates fibrosis in the liver, lungs, and respiratory tract. However, the mechanisms and roles of MFG‐E8 in skin fibrosis in systemic sclerosis (SSc) have not been characterized. We undertook this study to elucidate the role of MFG‐E8 in skin fibrosis in SSc.

Skin Sclerosis with Elevation of Serum Interleukin-6 That Is Possibly Associated with Immunoglobulin 4-Related Disease

Dear Editor: An 82-year-old Japanese man was found to have retroperitoneal fibrosis in 2006 and treated with 60 mg/day prednisolone, which tapered and finally discontinued in January 2010. Arthritis of both knees developed in 2011, and total knee arthroplasty was performed in January 2013. Histopathological examination of the joint synovium showed numerous infiltrations of plasma cells and fibrosis around the infiltrate (Fig. 1A). The ratio of immunoglobulin G4+ (IgG4+)/IgG+ plasma cells per high-power field was >60% (Fig. 1B). Serum IgG4 was elevated (125 mg/dl; reference, 4~108 mg/dl). IgG4-related disease (IgG4-RD) with involvement of the retroperitoneum and joint synovium was established. Computed tomography showed the remaining lesion of retroperitoneal fibrosis but did not show additional lesions of IgG4-RD. One month after the operation, he noticed an indurated skin lesion in his lower leg. Physical examination revealed diffuse, indurated skin sclerosis in his left lower leg (Fig. 1C). Histological examination revealed severe fibrosis in entire dermis and infiltrations of plasma cells around blood vessels (Fig. 1D). IgG4+ cells were rarely observed. Skin sclerosis appeared sequentially after the operation on the joint synovium and the establishment of the diagnosis of IgG4-RD, suggesting that skin sclerosis may be considered as the possible symptom of IgG4-RD. Topical and oral prednisolone (15 mg/day) was given. The skin sclerosis became soft gradually, and serum IgG4 levels returned to the reference range. We also found that the serum interleukin (IL)-6 level was elevated (13 pg/ml; reference, <0.5) before treatment and returned to the reference range in parallel with clinical improvement. Fig. 1 (A) Histopathological examination of the joint synovium. Infiltration of plasma cells and fibrosis (H&E, ×400). (B) Infiltration of IgG4+ plasma cells (×400)