Low-density lipoprotein receptor-related protein 6 ablation in macrophages differentially inhibits lung injury-mediated inflammation and metastasis.

Low-density lipoprotein receptor-related protein 6 (LRP6) is a receptor protein for Wnt ligands. Yet, their role in immune cell regulation remains elusive. Here we demonstrated that genetic deletion of LRP6 in macrophages using LysM-cre Lrp6fl/fl (Lrp6MKO) mice showed differential inhibition of inflammation in the bleomycin (BLM)-induced lung injury model and B16F10 melanoma lung metastasis model. Lrp6MKO mice showed normal immune cell populations in the lung and circulating blood in homeostatic conditions. In the BLM-induced lung injury model, Lrp6MKO mice showed a decreased number of monocyte-derived alveolar macrophages, reduced collagen deposition and alpha-smooth muscle actin (αSMA) protein levels in the lung. In B16F10 lung metastasis model, Lrp6MKO mice reduced lung tumor foci. Monocytic and granulocytic-derived myeloid-derived suppressor cells (M-MDSCs and G-MDSCs) were increased in the lung. In G-MDSCs, hypoxia-inducible factor 1α (HIF1α)+ PDL1+ population was markedly decreased but not in M-MDSCs. Taken together, our results show that the role of LRP6 in macrophages is differential depending on the inflammation microenvironment in the lung.

Thrombocyte-derived Dickkopf1 promotes macrophage polarization in the Bleomycin-induced lung injury model.

Immune responses are crucial to maintaining tissue homeostasis upon tissue injury. Upon various types of challenges, macrophages play a central role in regulating inflammation and tissue repair processes. While an immunomodulatory role of Wnt antagonist Dickkopf1 (DKK1) has been implicated, the role of Wnt antagonist DKK1 in regulating macrophage polarization in inflammation and the tissue repair process remains elusive. Here we found that DKK1 induces gene expression profiles to promote inflammation and tissue repair in macrophages. Importantly, DKK1 induced various genes, including inflammation and tissue repair, via JNK (c-jun N-terminal kinase) in macrophages. Furthermore, DKK1 potentiated IL-13-mediated macrophage polarization and activation. The co-inhibition of JNK and STAT6 markedly decreased gene expressions relevant to inflammation and fibrosis by DKK1 and IL-13. Interestingly, thrombocyte-specific deletion of DKK1 in mice reduced collagen deposition and decreased Arg1, CD206, HIF1α, and IL1ß protein expressions in monocyte-derived alveolar macrophages in the acute sterile bleomycin (BLM)-induced lung injury model. These data suggested that thrombocytes communicate with macrophages via DKK1 to orchestrate inflammation and repair in this model. Taken together, our study demonstrates DKK1's role as an important regulatory ligand for macrophage polarization in the injury-induced inflammation and repair process in the lung.

Phase III, Randomized, Double-Blind Study Comparing the Efficacy, Safety, and Immunogenicity of SB3 (Trastuzumab Biosimilar) and Reference Trastuzumab in Patients Treated With Neoadjuvant Therapy for Human Epidermal Growth Factor Receptor 2-Positive Early Breast Cancer.

Purpose This phase III study compared SB3, a trastuzumab (TRZ) biosimilar, with reference TRZ in patients with human epidermal growth factor receptor 2-positive early breast cancer in the neoadjuvant setting ( ClinicalTrials.gov identifier: NCT02149524). Patients and Methods Patients were randomly assigned to receive neoadjuvant SB3 or TRZ for eight cycles concurrently with chemotherapy (four cycles of docetaxel followed by four cycles of fluorouracil, epirubicin, and cyclophosphamide) followed by surgery, and then 10 cycles of adjuvant SB3 or TRZ. The primary objective was comparison of breast pathologic complete response (bpCR) rate in the per-protocol set; equivalence was declared if the 95% CI of the ratio was within 0.785 to 1.546 or the 95% CI of the difference was within ± 13%. Secondary end points included comparisons of total pathologic complete response rate, overall response rate, event-free survival, overall survival, safety, pharmacokinetics, and immunogenicity. Results Eight hundred patients were included in the per-protocol set (SB3, n = 402; TRZ, n = 398). The bpCR rates were 51.7% and 42.0% with SB3 and TRZ, respectively. The adjusted ratio of bpCR was 1.259 (95% CI, 1.085 to 1.460), which was within the predefined equivalence margins. The adjusted difference was 10.70% (95% CI, 4.13% to 17.26%), with the lower limit contained within and the upper limit outside the equivalence margin. The total pathologic complete response rates were 45.8% and 35.8% and the overall response rates were 96.3% and 91.2% with SB3 and TRZ, respectively. Overall, 96.6% and 95.2% of patients experienced one or more adverse event, 10.5% and 10.7% had a serious adverse event, and 0.7% and 0.0% had antidrug antibodies (up to cycle 9) with SB3 and TRZ, respectively. Conclusion Equivalence for efficacy was demonstrated between SB3 and TRZ on the basis of the ratio of bpCR rates. Safety and immunogenicity were comparable.

The association between regional arterial stiffness and diabetic retinopathy in type 2 diabetes.

OBJECTIVES: Although several studies have reported that PWV is associated with diabetic retinopathy, it remains controversial as to which segment provides the PWV that might best reflect the presence of retinopathy. The aim of this study was to determine the pulse wave velocity (PWV) of arterial segments that is most closely associated with diabetic retinopathy in subjects without a history of macrovascular complications. METHODS: After excluding subjects with a history of ischemic heart disease, peripheral artery disease, ischemic stroke, renal insufficiency, overt proteinuria, and other nondiabetic ophthalmic lesions or insufficient retinal examinations, a total of 494 subjects were analyzed by cross-sectional study. The central PWVs, including the heart-femoral (hf), heart-carotid (hc), heart-ankle (ha), and carotid-brachial (cb) segments, and the peripheral PWVs, including brachial-ankle (ba) and femoral-ankle (fa), were measured for each subject. RESULTS: The group with diabetic retinopathy exhibited significantly higher hfPWV, hcPWV, haPWV and baPWV, but notcbPWV, faPWV or augmentation index (AI). Age, duration of diabetes, systolic and diastolic BP and pulse pressure were all positively associated with hfPWV, hcPWV, haPWV and baPWV. Quartiles of hfPWV were significantly associated with diabetic retinopathy after adjustment for covariates and known risk factors of diabetic retinopathy (P for trend = 0.023). Conversely, all quartiles of haPWV, hcPWV and baPWV lost significance after adjustment. CONCLUSIONS: We found that diabetic retinopathy was most closely associated with hfPWV, suggesting the most reliable index of regional arterial stiffness index in retinopathy.

Inhibitory effect of YC-1, 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole, on experimental choroidal neovascularization in rat.

PURPOSE: It was the aim of this study to evaluate the effects of YC-1, 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole, one of the hypoxia-inducible factor 1 (HIF-1) inhibitors, on laser-induced choroidal neovascularization (CNV) in rats. METHODS: Thirty female Brown Norway rats underwent laser photocoagulation to induce CNV. Twenty of them (treatment group) were treated with a single intravitreal injection of 5 microg YC-1, and the remaining 10 (control) were sham-treated with a single intravitreal injection of 2.5 mg/ml dimethyl sulfoxide 2 weeks after laser photocoagulation. The expression of HIF-1alpha and vascular endothelial growth factor (VEGF) in CNV was evaluated by immunofluorescence staining. Fluorescein angiography was performed 2 weeks before and 2 weeks after single intravitreal YC-1 (5 microg) and dimethyl sulfoxide (2.5 mg/ml) injection, grading fluorescein leakage from 0 to 3. The size of the CNV was measured on histologic sections. RESULTS: Both HIF-1alpha and VEGF were expressed in CNV lesions in the control group 4 weeks after laser photocoagulation, whereas the expressions of HIF-1alpha and VEGF were not observed in the intravitreally YC-1-treated group. The mean fluorescein leakage score decreased from 2.56 +/- 0.49 to 0.79 +/- 0.71 in the intravitreally YC-1-injected group and from 2.62 +/- 0.49 to 1.58 +/- 0.60 in the control group. Sixty-eight (71.6%) out of 95 CNV lesions of intravitreally YC-1-treated eyes (71.4%) and 12 (21.8%) out of 55 lesions in DMSO-treated eyes showed a decreased fluorescein leakage score of 2 or more. The mean difference of fluorescein leakage scores between the intravitreally YC-1-treated group and the control group was significant (p = 0.004). The mean thickness of the CNV lesions in the intravitreally YC-1-treated group (27.30 +/- 6.47 microm) was smaller than that of the control group (64.36 +/- 8.26 microm, p < 0.001). There was no ocular inflammation, retina hemorrhage or systemic toxicity induced by YC-1 treatment. CONCLUSION: These results suggest that YC-1 inhibits the HIF-1 expression after photocoagulation and suppresses the development of laser-induced CNV formation.

Multifocal electroretinogram responses of the clinically normal retinal areas in diabetes.

AIMS: To investigate the degree of implicit time delay in aretinopathic hexagons according to the grading of diabetic retinopathy and factors that affect the mfERG responses of aretinopathic areas. METHODS: MfERG was recorded using the RETIscan system (Roland consult, Brandenbrug, Germany) in 40 eyes of 20 nondiabetic controls, 32 eyes of 16 diabetic patients without retinopathy, and 96 eyes of 48 diabetic patients with nonproliferative diabetic retinopathy (NPDR). Hexagons are divided into retinopathic and aretinopathic hexagons, which were selected using fundus photographs and fluorescence angiography. Relative amplitude and implicit time delay were compared between patient groups and controls. RESULTS: The mean implicit time delay in aretinopathic hexagons was significantly different between each subject group and correlated with the retinopathy severity of the whole retina, as well as in retinopathic hexagons. In all three NPDR groups, implicit time was significantly more delayed in retinopathic hexagons compared to aretinopathic hexagons. Relative amplitude was significantly decreased only in the severe NPDR group in both retinopathic and aretinopathic hexagons. The duration of diabetes and glycemic control status did not correlate with the local mfERG responses. CONCLUSIONS: Local mfERG showed considerable implicit time delays in clinically normal retinal areas that correlated significantly with the severity of diabetic retinopathy of the whole retina.