Matrix metalloproteinase-1 up-regulation by hepatocyte growth factor in human dermal fibroblasts via ERK signaling pathway involves Ets1 and Fli1

In this study, we clarified the molecular mechanism(s) underlying the regulation of matrix metalloproteinase (MMP)-1 gene by hepatocyte growth factor (HGF) in cultured human dermal fibroblasts. HGF induced MMP-1 protein as well as mRNA at a transcriptional level via extracellular signal-regulated kinase (ERK) signaling pathway. The region in the MMP-1 promoter mediating the inducible responsiveness to HGF, defined by the transient transfection analysis of the serial 5′ deletion constructs, contained an Ets binding site. Mutation of this Ets binding site abrogated the HGF-inducible promoter activity. Ets1 up-regulated the expression of MMP-1 promoter activity, whereas Fli1 had antagonistic effects on them. After HGF treatment, the protein level and the binding activity of Ets1 was increased and those of Fli1 was decreased, which were canceled by PD98059. These results suggest that HGF up-regulates MMP-1 expression via ERK signaling pathway through the balance of Ets1 and Fli1, which may be a novel mechanism of regulating MMP-1 gene expression

A New Disorder in UV-Induced Skin Cancer with Defective DNA Repair Distinct from Xeroderma Pigmentosum or Cockayne Syndrome

We report the characterization of a Japanese woman who exhibited many freckles and skin cancers in sun-exposed areas, but displayed no photosensitivity. Fibroblasts (KPSX7) derived from this patient showed similar UV sensitivity to that of normal human fibroblasts. The KPSX7 cells showed normal levels of unscheduled DNA synthesis, recovery of RNA synthesis, recovery of replicative DNA synthesis, protein-binding ability to UV-damaged DNA, and post-translational modification of xeroderma pigmentosum (XP) C. These results indicate that the patient had neither XP nor Cockayne syndrome. Although these results suggest that the KPSX7 cells were proficient in nucleotide excision repair activity, host-cell reactivation (HCR) activity of KPSX7 cells was reduced. Furthermore, introduction of UV damage endonuclease into the cells restored repair activity in the HCR assay to almost normal levels. These results indicate that KPSX7 cells are defective for some types of repair activity in UV-damaged DNA. In summary, the patient had a previously unknown disorder related to UV-induced carcinogenesis, with defective DNA repair

Connective Tissue Growth Factor Gene Expression in Tissue Sections From Localized Scleroderma, Keloid, and Other Fibrotic Skin Disorders

Connective tissue growth factor (CTGF) is a novel peptide that exhibits platelet-derived growth factor-like activities and is produced by skin fibroblasts after activation with transforming growth factor-β. Coordinate expression of transforming growth factor-β followed by CTGF during wound repair suggests a cascade process for control of tissue regeneration. We recently reported a significant correlation between CTGF mRNA expression and histologic sclerosis in systemic sclerosis. To confirm the relation between CTGF and skin fibrosis, we investigated CTGF gene expression in tissue sections from patients with localized scleroderma, keloid, and other sclerotic skin disorders using nonradioactive in situ hybridization. In localized scleroderma, the fibroblasts with positive signals for CTGF mRNA were scattered throughout the sclerotic lesions with no preferential distribution around the inflammatory cells or perivascular regions, whereas the adjacent nonaffected dermis was negative for CTGF mRNA. In keloid tissue, the fibroblasts positive for CTGF mRNA were diffusely distributed, especially in the peripheral expanding lesions. In scar tissue, however, the fibroblasts in the fibrotic lesions showed partially positive signals for CTGF mRNA. In eosinophilic fasciitis, nodular fasciitis, and Dupuytren's contracture, CTGF mRNA was also expressed partially in the fibroblasts of the fibrotic lesions. Our findings reinforce a correlation between CTGF gene expression and skin sclerosis and support the hypothesis that transforming growth factor-β plays an important role in the pathogenesis of fibrosis, as it is the only inducer for CTGF identified to date

Efficacy and safety of nivolumab in Japanese patients with previously untreated advanced melanoma: A phase II study

Treating advanced or recurrent melanoma remains a challenge. Cancer cells canevade the immune system by blocking T-cell activation through overexpressionof the inhibitory receptor programmed death 1 (PD-1) ligands. The PD-1 inhibitornivolumab blocks the inhibitory signal in T cells, thus overcoming the immuneresistance of cancer cells. Nivolumab has shown promising anticancer activity invarious cancers. We carried out a single-arm, open-label, multicenter, phase IIstudy to investigate the efficacy and safety of nivolumab in previously untreatedJapanese patients with advanced melanoma. Twenty-four patients with stage III/IV or recurrent melanoma were enrolled and received i.v. nivolumab 3 mg/kgevery 2 weeks until disease progression or unacceptable toxicity. The primaryendpoint was overall response rate evaluated by an independent radiologyreview committee. The independent radiology review committee-assessed overallresponse rate was 34.8% (90% confidence interval, 20.8–51.9), and the overallsurvival rate at 18 months was 56.5% (90% confidence interval, 38.0–71.4). Treatment-related adverse events (AEs) of grade 3 or 4 only occurred in three patients(12.5%). Two patients discontinued nivolumab because of AEs, but all AEs wereconsidered manageable by early diagnosis and appropriate treatment. Subgroupanalyses showed that nivolumab was clinically beneficial and tolerable regardlessof BRAF genotype, and that patients with treatment-related select AEs and withvitiligo showed tendency for better survival. In conclusion, nivolumab showedfavorable efficacy and safety profiles in Japanese patients with advanced orrecurrent melanoma, with or without BRAF mutations. (Trial registration no.JapicCTI-142533.

Long‐term follow up of nivolumab in previously untreated Japanese patients with advanced or recurrent malignant melanoma

The immune checkpoint inhibitor nivolumab inhibits the programmed death 1 receptor and suppresses the immune resistance of cancer cells. This is a long-term follow up of a single-arm, open-label, multicenter, phase II study of nivolumab in untreated Japanese patients with stage III/IV or recurrent melanoma. In addition, a post-hoc subgroup analysis stratified by melanoma types was performed. Nivolumab was administered intravenously at a dose of 3 mg/kg every 2 weeks. The primary endpoint was the overall response rate (ORR), and secondary endpoints included overall survival (OS), progression-free survival (PFS), best overall response, the disease control rate and change in tumor diameter. Safety was assessed by recording treatment-related adverse events (TRAE), including select immune-related adverse events. Of the 24 patients initially included in the primary phase II study, 10 survived for over 3 years (41.7%). The ORR was 34.8% (90% confidence interval [CI]: 20.8, 51.9) for all patients. When analyzing by melanoma type, the ORR was 66.7% (90% CI: 34.7, 88.3) for superficial spreading, 33.3% (90% CI: 11.7, 65.3) for mucosal, and 28.6% (90% CI: 10.0, 59.1) for acral lentiginous tumors. The median OS was 32.9 months, the 3-year OS rate was 43.5%, and the 3-year PFS rate was 17.2%. A long-term response was observed in all the tumor types. The most common TRAE included skin toxicity (45.8%) and endocrine disorders (29.2%). This study demonstrated the long-term efficacy and tolerability of nivolumab in patients with advanced or recurrent melanoma, irrespective of melanoma type

Cytokine biomarkers to predict antitumor responses to nivolumab suggested in a phase 2 study for advanced melanoma

Promising antitumor activities of nivolumab, a fully humanized IgG4 inhibitor antibody against the programmed death-1 protein, were suggested in previous phase 1 studies. The present phase 2, single-arm study (JAPIC-CTI #111681) evaluated the antitumor activities of nivolumab and explored its predictive correlates in advanced melanoma patients at 11 sites in Japan. Intravenous nivolumab 2 mg/kg was given repeatedly at 3-week intervals to 35 of 37 patients enrolled from December 2011 to May 2012 until they experienced unacceptable toxicity, disease progression, or complete response. Primary endpoint was objective response rate. Serum levels of immune modulators were assessed at multiple time points. As of 21 October 2014, median response duration, median progression-free survival, and median overall survival were 463 days, 169 days, and 18.0 months, respectively. The overall response rate and 1- and 2-year survival rates were 28.6%, 54.3%, and 42.9%, respectively. Thirteen patients remained alive at the end of the observation period and no deaths were drug related. Grade 3–4 drug-related adverse events were observed in 31.4% of patients. Pretreatment serum interferon-γ, and interleukin-6 and -10 levels were significantly higher in the patients with objective tumor responses than in those with tumor progression. In conclusion, giving repeated i.v. nivolumab had potent and durable antitumor effects and a manageable safety profile in advanced melanoma patients, strongly suggesting the usefulness of nivolumab for advanced melanoma and the usefulness of pretreatment serum cytokine profiles as correlates for predicting treatment efficacy

Phase 1b study of pembrolizumab (MK-3475; anti-PD-1 monoclonal antibody) in Japanese patients with advanced melanoma (KEYNOTE-041)

PurposeThis phase I b study evaluated the safety and anti-tumor activity of pembrolizumab in Japanese patients with advanced melanoma.MethodsPembrolizumab (2 mg/kg) was given every 3 weeks (Q3W) for up to 2 years or until confirmed progression or unacceptable toxicity. The tumor response was assessed as per the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1) by both investigator review and central review.ResultsForty-two patients with advanced melanoma received pembrolizumab. A primary cutaneous histology was observed in 34 patients (81.0%), while a primary mucosal histology was observed in 8 patients (19.0%). Thirty-four patients (81.0%) experienced treatment-related adverse events (AEs). The most common treatment-related AEs were pruritus, maculopapular rash, malaise, and hypothyroidism. Grade 3–5 treatment-related AEs occurred in 8 patients (19.0%). The only grade 3–5 treatment-related AE reported in at least two patients was anemia. There were two treatment-related deaths (unknown cause and cerebral hemorrhage). Among the 37 evaluable patients, the confirmed overall response rates (ORRs) determined by central review were 24.1% (95% CI 10.3–43.5) for cutaneous melanoma and 25.0% (95% CI 3.2–65.1) for mucosal melanoma. The responses were durable, and the median duration of response was not reached in either population. The median overall survival (OS) was not reached, with a 12-month OS of 82.7% for cutaneous melanoma and 51.4% for mucosal melanoma.ConclusionThe safety profile of pembrolizumab in Japanese patients was similar to that reported in the previous clinical studies. Pembrolizumab provided promising anti-tumor activity in Japanese patients with advanced melanoma

Upregulation of ANGPTL6 in mouse keratinocytes enhances susceptibility to psoriasis

Psoriasis is a chronic inflammatory skin disease marked by aberrant tissue repair. Mutant mice modeling psoriasis skin characteristics have provided useful information relevant to molecular mechanisms and could serve to evaluate therapeutic strategies. Here, we found that epidermal ANGPTL6 expression was markedly induced during tissue repair in mice. Analysis of mice overexpressing ANGPTL6 in keratinocytes (K14-Angptl6 Tg mice) revealed that epidermal ANGPTL6 activity promotes aberrant epidermal barrier function due to hyperproliferation of prematurely differentiated keratinocytes. Moreover, skin tissues of K14-Angptl6 Tg mice showed aberrantly activated skin tissue inflammation seen in psoriasis. Levels of the proteins S100A9, recently proposed as therapeutic targets for psoriasis, also increased in skin tissue of K14-Angptl6 Tg mice, but psoriasis-like inflammatory phenotypes in those mice were not rescued by S100A9 deletion. This finding suggests that decreasing S100A9 levels may not ameliorate all cases of psoriasis and that diverse mechanisms underlie the condition. Finally, we observed enhanced levels of epidermal ANGPTL6 in tissue specimens from some psoriasis patients. We conclude that the K14-Angptl6 Tg mouse is useful to investigate psoriasis pathogenesis and for preclinical testing of new therapeutics. Our study also suggests that ANGPTL6 activation in keratinocytes enhances psoriasis susceptibility