ヒト間葉系幹細胞はエオタキシン3/CCR3経路を介して前立腺癌細胞の浸潤能を増加させる

This study aimed to clarify the role of mesenchymal stem cells (MSCs) as a component of the cancer microenvironment. We investigated the homing-related chemokine expression levels of MSCs treated with a prostate cancer cell line (PC-3) -conditioned medium. Among several homing chemokines, an antibody array revealed that expression of eotaxin-3 (but not eotxin-1 and -2) was highly enhanced in MSCs treated with PC-3-conditioned medium. A gene expression array showed significantly increased expression of CCR3, a receptor of eotaxin-3, in PC-3. In a matrigel invasion assay, interferon-gamma, a specific inhibitor of eotaxin-related homing, significantly reduced the transmigration of PC-3 cells, under co-cultured condition with MSCs, in a dose-dependent manner (P < 0.05). Consistent with these results, anti-CCR3 antibody successfully reduced PC-3 migration under the co-cultured condition. These findings suggest that MSCs to modulation of the invasive potential of prostate cancer cells via the eotaxin-3/CCR3 axis.博士（医学）・乙第1424号・平成30年11月30日© 2018 Elsevier GmbH. All rights reserved

胃癌における免疫チェックポイント阻害薬の副作用と効果の関連性

Recently, immune checkpoint inhibitors（ICI）have been approved for use in advanced gastric cancer（AGC）based on the positive results of ATTRACTION‐２ trial in Japan. There has been accumulating evidence that the development of immune-related adverse events（irAE）may be associated with a response to ICI therapy, particularly in lung cancer, although little is known about these correlations in gastrointestinal cancer. To investigate the efficacy and irAE of ICI treatment and their correlation in AGC, we retrospectively examined ２９ patients with AGC who received nivolumab therapy in our departments. Among them, １５ patients（５２％）developed irAEs including ４ patients（１４％）for grade ３ irAEs ; liver dysfunction（n＝２）, type １ diabetes mellitus（n＝２） and adrenal insufficiency（n＝１）. The median overall survival was１２．０months in the irAE group and ３．２５ months in the non-irAE group（p＝０．１６４）, which suggested the relationship between the effects and irAEs in ICI treatment of AGC. Further research is required to understand the implications of irAE characteristics on ICI response in GCA patients

First-line pembrolizumab vs chemotherapy in metastatic non-small-cell lung cancer: KEYNOTE-024 Japan subset

This prespecified subanalysis of the global, randomized controlled phase Ill KEYNOTE-024 study of pembrolizumab vs chemotherapy in previously untreated metastatic non-small-cell lung cancer without EGFR/ALK alterations and a programmed death-ligand 1 (PD-L1) tumor proportion score of 50% or greater evaluated clinical outcomes among patients enrolled in Japan. Treatment consisted of pembrolizumab 200 mg every 3 weeks (35 cycles) or platinum-based chemotherapy (four to six cycles). The primary end-point was progression-free survival; secondary end-points included overall survival and safety. Of 305 patients randomized in KEYNOTE-024 overall, 40 patients were enrolled in Japan (all received treatment: pembrolizumab, n = 21; chemotherapy, n = 19). The hazard ratio (HR) for progression-free survival by independent central review (data cut-off date, 10 July 2017) was 0.25 (95% confidence interval [CI], 0.10-0.64; one-sided, nominal P = .001). The HR for overall survival (data cut-off date, 15 February 2019) was 0.39 (95% CI, 0.17-0.91; one-sided, nominal P = .012). Treatment-related adverse events occurred in 21/21 (100%) pembrolizumab-treated and 18/19 (95%) chemotherapy-treated patients; eight patients (38%) and nine patients (47%), respectively, had grade 3-5 events. Immune-mediated adverse events and infusion reactions occurred in 11 patients (52%) and four patients (21%), respectively; four patients (19%) and one patient (5%), respectively, had grade 3-5 events. Consistent with results from KEYNOTE-024 overall, first-line pembrolizumab improved progression-free survival and overall survival vs chemotherapy with manageable safety among Japanese patients with metastatic non-small-cell lung cancer without EGFRIALK alterations and a PD-L1 tumor proportion score of 50% or greater

First-line pembrolizumab vs chemotherapy in metastatic non-small-cell lung cancer: KEYNOTE-024 Japan subset

This prespecified subanalysis of the global, randomized controlled phase III KEYNOTE‐024 study of pembrolizumab vs chemotherapy in previously untreated metastatic non‐small‐cell lung cancer without EGFR/ALK alterations and a programmed death ligand 1 (PD‐L1) tumor proportion score of 50% or higher evaluated clinical outcomes among patients enrolled in Japan. Treatment consisted of pembrolizumab 200 mg every 3 weeks (35 cycles) or platinum‐based chemotherapy (four to six cycles). The primary end‐point was progression‐free survival; secondary end‐points included overall survival and safety. Of 305 patients randomized in KEYNOTE‐024 overall, 40 patients were enrolled in Japan (all received treatment: pembrolizumab, n = 21; chemotherapy, n = 19). Median progression‐free survival was 41.4 (95% confidence interval [CI], 4.2‐42.5) months with pembrolizumab and 4.1 (95% CI, 2.8‐8.3) months with chemotherapy (hazard ratio [HR], 0.27 [95% CI, 0.11‐0.65]; one‐sided, nominal P = .001). Median overall survival was not reached (NR) (95% CI, 22.9‒NR) and 21.5 (95% CI, 5.2‐35.0) months, respectively (HR, 0.39 [95% CI, 0.17‐0.91]; one‐sided, nominal P = .012). Treatment‐related adverse events occurred in 21/21 (100%) pembrolizumab‐treated and 18/19 (95%) chemotherapy‐treated patients; eight patients (38%) and nine patients (47%), respectively, had grade 3‐5 events. Immune‐mediated adverse events and infusion reactions occurred in 11 pembrolizumab‐treated patients (52%) and four chemotherapy‐treated patients (21%), respectively; four patients (19%) and one patient (5%), respectively, had grade 3‐5 events. Consistent with results from KEYNOTE‐024 overall, first‐line pembrolizumab improved progression‐free survival and overall survival vs chemotherapy with manageable safety among Japanese patients with metastatic non‐small‐cell lung cancer without EGFR/ALK alterations and a PD‐L1 tumor proportion score of 50% or higher. The trial is registered with Clinicaltrials.gov: NCT02142738

A frequent nonsense mutation in exon 1 across certain HLA-A and -B alleles in leukocytes of patients with acquired aplastic anemia

Leukocytes that lack HLA allelic expression are frequently detected in patients with acquired aplastic anemia (AA) who respond to immunosuppressive therapy (IST), although the exact mechanisms underlying the HLA loss and HLA allele repertoire likely to acquire loss-of-function mutations are unknown. We identified a common nonsense mutation at position 19 (c.19C>T, p.R7X) in exon 1 (Exon1mut) of different HLA-A and -B alleles in HLA-lacking granulocytes from AA patients. A droplet digital PCR (ddPCR) assay capable of detecting as few as 0.07% Exon1mut HLA alleles in total DNA revealed the mutation was present in 29% (101/353) of AA patients, with a median allele frequency of 0.42% (range, 0.071% to 21.3%). Exon1mut occurred in only 12 different HLA-A (n=4) and HLA-B (n=8) alleles, including B*40:02 (n=31) and A*02:06 (n=15), which correspond to 4 HLA supertypes (A02, A03, B07, and B44). The percentages of patients who possessed at least one of these 12 HLA alleles were significantly higher in the 353 AA patients (92%,