Co-expression of regulatory B-cell markers, transforming growth factor β and interleukin-10 as a prognostic factor in diffuse large B-cell lymphoma

Regulatory B cells (Bregs) suppress antitumor immunity by producing anti-inflammatory cytokines such as transforming growth factor β (TGF-β) and interleukin-10 (IL-10) and promoting tumor growth. It is unknown whether diffuse large B-cell lymphoma (DLBCL), a common subtype of B-cell malignancy, exhibits characteristics similar to those of Bregs. This study aimed to clarify the features of DLBCLs carrying Breg markers. In 123 DLBCL cases, we evaluated TGF-β and IL-10 expression in tumor biopsy samples using immunohistochemical staining and retrospectively analyzed their clinicopathological characteristics. Fifteen cases (12.2 %) classified as Breg-type DLBCL were positive for both TGF-β and IL-10. Breg-type DLBCL is mainly classified as having activated B cell-like cells of origin. Breg-type DLBCL cases showed significantly worse progression-free survival and overall survival (OS) than other DLBCL cases (P = 0.0016 and P = 0.042, respectively). In multivariate analysis, Breg-type DLBCL significantly affected OS (hazard ratio, 3.13; 95 % confidence interval 1.15-8.55; P = 0.025). Gene expression analysis showed that the expression of follicular dendritic cell-associated genes (FCER2, PIK3CD, FOXO1) was downregulated in Breg-type DLBCLs compared to other DLBCLs. These results suggest that the double expression of Breg markers, TGF-β and IL-10, in tumor cells indicates a poor prognosis in DLBCL patients. Further studies evaluating genomic abnormalities could confirm the characteristics of Breg-type DLBCL.

Clinicopathological analysis of CD47 and signal regulatory protein alpha expression in myeloid sarcoma patients: CD47 expression is a favourable prognostic factor

Myeloid sarcoma is a rare extramedullary haematopoietic malignancy. Interaction between CD47 and signal regulatory protein α (SIRPα) inhibits phagocytosis. CD47-positive tumours confer poor prognoses in various malignant tumours, including acute myeloid leukaemia. This study aimed to investigate the clinicopathological effects of CD47 and SIRPα expression in myeloid sarcoma. Immunohistochemistry (IHC) of CD47 and SIRPα was performed in 84 biopsy samples obtained from patients with myeloid sarcoma, some of which were CD47-positive. Patients were categorised into the following two groups based on IHC of SIRPα: those with SIRPα-positive neoplastic cells (nSIRPα) and, SIRPα expression on non-neoplastic stromal cells in tumour microenvironment (miSIRPα). In addition, patients with CD47 positivity had higher lymphocytic infiltration into the tumour microenvironment. Overall, these patients had significantly higher overall survival, however, no significant difference was observed in progression-free survival. No significant prognostic differences were observed between the nSIRPα and miSIRPα groups. This is the first study to demonstrate an association between CD47 expression and improved prognosis in myeloid sarcoma. Nonetheless, it will be necessary to conduct additional research on gene expression and genomic abnormalities to elucidate the corresponding pathogenesis of myeloid sarcoma.

Clinicopathological comparison between PTCL-TBX21 and PTCL-GATA3 in Japanese patients

AIM

Peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) is a heterogeneous disease that can be classified into the PTCL-TBX21 and PTCL-GATA3 subtypes.

METHODS

In this study, we compared the clinicopathological features of PTCL-NOS in a Japanese cohort, classified using an IHC algorithm.

RESULTS

One hundred patients with PTCL-NOS were categorized as having PTCL-TBX21 (n = 55), PTCL-GATA3 (n = 24), or PTCL-unclassified (n = 21). When comparing PTCL-TBX21 and PTCL-GATA3, PTCL-TBX21 showed significantly lower CD4 positivity (p = 0.047), lower counts of high endothelial venules (p = 0.032), and a tendency for a better response to initial treatment (p = 0.088). Gene expression analysis using the nCounter system showed higher expression of tumor immunity-related genes, such as PD-L1, LAG3, and IDO1, in PTCL-TBX21 than in PTCL-GATA3. PTCL-GATA3 had significantly worse overall survival (OS) than those with PTCL-TBX21 (p = 0.047), although a similar tendency was observed for progression-free survival (PFS) (p = 0.064). PTCL-GATA3 was a prognostic factor for OS in univariate analysis (HR 2.02; 95% CI, 1.09-3.77; p = 0.027), although multivariate analysis did not show significance (HR 2.07; 95% CI, 0.93-4.61; p = 0.074). In the PFS analysis, PTCL-GATA3 was an independent prognostic factor by univariate analysis (HR 1.96; 95% CI, 1.08-3.56; p = 0.027) and multivariate analysis (HR 2.34; 95% CI, 1.07-5.11; p = 0.032).

CONCLUSION

The classification of PTCL-NOS into PTCL-TBX21 and PTCL-GATA3 is useful for predicting the prognosis of Japanese patients and stratifying the administration of tumor immune checkpoint inhibitors in clinical practice.

Case-based similar image retrieval for weakly annotated large histopathological images of malignant lymphoma using deep metric learning

In the present study, we propose a novel case-based similar image retrieval (SIR) method for hematoxylin and eosin (H&E) stained histopathological images of malignant lymphoma. When a whole slide image (WSI) is used as an input query, it is desirable to be able to retrieve similar cases by focusing on image patches in pathologically important regions such as tumor cells. To address this problem, we employ attention-based multiple instance learning, which enables us to focus on tumor-specific regions when the similarity between cases is computed. Moreover, we employ contrastive distance metric learning to incorporate immunohistochemical (IHC) staining patterns as useful supervised information for defining appropriate similarity between heterogeneous malignant lymphoma cases. In the experiment with 249 malignant lymphoma patients, we confirmed that the proposed method exhibited higher evaluation measures than the baseline case-based SIR methods. Furthermore, the subjective evaluation by pathologists revealed that our similarity measure using IHC staining patterns is appropriate for representing the similarity of H&E stained tissue images for malignant lymphoma.

Direct observation of Mn distribution/speciation within and surrounding a basidiomycete fungus in the production of Mn-oxides important in toxic element containment

Biogenic manganese (Mn) oxides occur ubiquitously in the environment including the uranium (U) mill tailings at the Ningyo-toge U mine in Okayama, Japan, being important in the sequestration of radioactive radium. To understand the nanoscale processes in Mn oxides formation at the U mill tailings site, Mn²⁺ absorption by a basidiomycete fungus, Coprinopsis urticicola, isolated from Ningyo-toge mine water samples, was investigated in the laboratory under controlled conditions utilizing electron microscopy, synchrotron-based X-ray analysis, and fluorescence microscopy with a molecular pH probe. The fungus' growth was first investigated in an agar-solidified medium supplemented with 1.0 mmol/L Mn²⁺, and Cu²⁺ (0-200 μM), Zn²⁺ (0-200 μM), or diphenyleneiodonium (DPI) chloride (0-100 μM) at 25 °C. The results revealed that Zn²⁺ has no significant effects on Mn oxide formation, whereas Cu²⁺ and DPI significantly inhibit both fungal growth and Mn oxidation, indicating superoxide-mediated Mn oxidation. Indeed, nitroblue tetrazolium and diaminobenzidine assays on the growing fungus revealed the production of superoxide and peroxide. During the interaction of Mn²⁺ with the fungus in solution medium at the initial pH of 5.67, a small fraction of Mn²⁺ infiltrated the fungal hyphae within 8 h, forming a few tens of nm-sized concentrates of soluble Mn²⁺ in the intracellular pH of ∼6.5. After 1 day of incubation, Mn oxides began to precipitate on the hyphae, which were characterized as fibrous nanocrystals with a hexagonal birnessite-structure, these forming spherical aggregates with a diameter of ∼1.5 μm. These nanoscale processes associated with the fungal species derived from the Ningyo-toge mine area provide additional insights into the existing mechanisms of Mn oxidation by filamentous fungi at other U mill tailings sites under circumneutral pH conditions. Such processes add to the class of reactions important to the sequestration of toxic elements.

Clinicopathological analysis of immunohistochemical expression of immune checkpoint molecules in follicular lymphoma

Follicular lymphoma (FL) is characterized by an indolent clinical course and a high relapse rate, and often exhibits a diffuse pattern beyond the follicular area. Our group previously reported that immune checkpoint (ICP) pathways, such as programmed cell death (PD-1) and programmed death ligand 1 (PD-L1), are poor prognostic factors for diffuse large B-cell lymphoma and adult T-cell leukemia/lymphoma.In this study, the association between the expression of multiple ICP molecules according to immunohistochemistry and clinicopathological features in FL was determined via immunostaining of 173 biopsy samples. Membrane and/or cytoplasm expression of CD86 (nCD86) and PD-L1 (nPD-L1) was found in tumor cells, whereas PD-1 (miPD-1), Galectin-9 (miGalectin-9), OX40 (miOX40), CTLA-4 (miCTLA-4), Tim-3 (miTim-3), OX40L (miOX40L), and LAG-3 (miLAG-3) were expressed in non-neoplastic stromal cells. MiPD-1 expression was significantly higher in the follicular area than in the diffuse area (p=0.0450). Expression of miOX40 and miCTLA-4 was significantly higher in the diffuse area than in the follicular area (respectively, p=0.0053 and p=0.0092). MiTim-3 tended to be higher in the diffuse area than in the follicular area (p=0.0616). MiTim-3 was significantly higher in relapse cases than in new-onset cases (p=0.0440); miLAG-3 tended to be higher in relapse cases than in new-onset cases (p=0.0622, not significant). The miOX40L-high FL group had a significantly worse overall survival than the miOX40L-low group (p=0.0320).The expression of multiple ICP molecules on several cells reflects activated anti-tumor immunity and the unique FL microenvironment. Further studies on gene expression or genomic abnormalities will reveal the clinical and biological significance of ICP molecules in FL. This article is protected by copyright. All rights reserved.

Association between adherence to home-based walking exercise with a pedometer and one-year adverse outcomes among lower extremity peripheral artery disease patients with endovascular treatment

Background

Home-based exercise after endovascular treatment (EVT) for lower extremity peripheral artery disease (LE-PAD) patients with intermittent claudication is suggested as an alternative therapy for supervised exercise; however, an association of adherence to home-based exercise with clinical adverse events has not been fully investigated.

Purpose

We aimed to investigate the association of adherence to home-based exercise with 1-year major adverse events (MAE), patency, and leg symptoms after EVT in a contemporary Japanese registry.

Methods

A total of 500 patients with LE-PAD within the Long Term Outcome of Endovascular Therapy for PAD with Intermittent Claudication Observational Prospective Multicenter (ASHIMORI-IC) registry (UMINCTR, UMINehab724.203718753) who underwent EVT between January 2016 and March 2019 were included in the analysis. After EVT, all patients were instructed to do home-based walking exercise with a pedometer. The study population was divided and compared between 2 groups according to adherence to home-based exercise: well-adherence and poor-adherence. The adherence of home-based exercise was as defined by step count derived from a pedometer on sites. The primary outcome was MAE defined as composite of all-cause death, myocardial infarction, stroke, target vessel revascularization, and major amputation of target lower limb for one year. The main secondary outcome was 1-year primary patency of the treated lesion, and the improvement of leg symptom (6-minute walk distance [6MWD] and claudication distance). The study followed the Consensus definitions from peripheral academic research consortium criteria.

Results

Overall, the mean age was 72.8 years, and 78% were men. At 1 year, MAE occurred in 45 patients (9.0%), and the primary patency rate was 85.3% (94.2% of EVT for aortoiliac and 71.9% of EVT for femoropopliteal). A significant difference in the incidence of MAE was observed between the well-adherence group and the poor-adherence group (10 of 233 patients [4.3%] vs. 35 of 267 patients [13.1%]; P<0.001). After multivariate Cox regression analysis, patients in the well-adherence group showed the lower hazard ratio for 1-year MAE (0.30; 95% confidence interval, 0.15–0.58; P<0.001) compared to those in the poor-adherence group. In the well-adherence group, compared with the poor-adherence group, higher primary patency rate (88.9% vs 81.5%; p=0.015), longer claudication onset distance (370 m [IQR 240–453 m] vs 240m [IQR 126–324 m]; P<0.001), and longer 6MWD (422 m [IQR 359–483 m] vs 325 m [IQR 213–400 m]; P<0.001) were observed even after adjusting for each baseline value.

Conclusion

Our study demonstrates the importance of adherence to home-based walking exercise after EVT in LE-PAD patients.

Funding Acknowledgement

Type of funding sources: None.

DA-EPOCH-R therapy for high-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements in a patient with renal dysfunction

High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements, also known as double-hit lymphoma, has been reported as refractory to R-CHOP therapy and requires more intensive regimens. However, intensive and safe regimens for patients with renal dysfunction are unknown. Herein, we report the successful use of DA-EPOCH-R therapy for double-hit lymphoma in a 64-year-old man with renal dysfunction. The patient had lymphoma-induced bilateral ureteral obstruction. Although renal dysfunction remained after removing the obstruction using R-CHOP therapy, we completed six cycles of DA-EPOCH-R therapy without any major adverse events. DA-EPOCH-R therapy may be a safe regimen for renal dysfunction patients.

Autoimmune myelofibrosis associated with systemic lupus erythematosus: a case report

A 66-year-old woman presented with severe anaemia, thrombocytopenia and lymphopenia. The bone marrow biopsy demonstrated hypocellular marrow with myelofibrosis (MF); there was no evidence of malignancy, but infiltration of peripheral T and B cells were noticed. Magnetic resonance imaging (MRI) revealed that bone marrow of the spine exhibited low signal intensity (SI) with spotty high SI in T1- and T2-weighted images. Because there was evidence of autoimmune abnormality, she had fulfilled the classification criteria for systemic lupus erythematosus (SLE). She was diagnosed with autoimmune myelofibrosis (AIMF) associated with SLE and was treated with corticosteroid. Cytopenia improved after 1 month of corticosteroid therapy. A repeated bone marrow biopsy demonstrated that cellularity had increased and that the amount of reticulin fibre had reduced after treatment. Compared with primary MF, AIMF has generally a favourable prognosis and is often associated with autoimmune diseases, especially SLE. Bone marrow biopsy, but not aspiration, was useful for diagnosing bone marrow fibrosis. Although the association between SLE and MF has been rarely reported, we should pay attention to MF as a possible cause of pancytopenia.

Cytokine-related genes play critical roles in extrafollicular growth of follicular lymphoma cells

Follicular lymphoma (FL) is a germinal center-derived B-cell lymphoma that is known to proliferate in the intrafollicular region. However, lymphoma cells can be identified in the extrafollicular regions, which are related to disease dissemination. We purified the intrafollicular and extrafollicular regions of FL cells by laser microdissection and conducted microarray analysis in order to characterize the gene expression profiles of FL cells from both regions. BCL2 and genes of germinal B-cell markers clearly separated intrafollicular and extrafollicular regions of reactive follicular hyperplasia, suggesting the adequacy of the current analysis. In FL cases, cytokine-related genes were significantly enriched in extrafollicular regions compared with those in the intrafollicular regions. In intrafollicular regions of FL, cell-cycle-related genes were enriched. We found that the FL cells in the extrafollicular region more strongly expressed IL3RA and CXCL12 than those of intrafollicular regions. The cytokines might be also derived from stroma cells in the extrafollicular regions, which may initiate activation and migration of the tumor cells to this region. Our results suggest that FL cell interaction with surrounding stroma cells plays an important role in the pathophysiology of FL and that such interactions should be a good target for therapy.

Combination of CD47 and signal-regulatory protein-α constituting the "don't eat me signal" is a prognostic factor in diffuse large B-cell lymphoma

The interaction between CD47 and signal‐regulatory protein‐α (SIRPα) inhibits phagocytosis, thus affecting the clinical outcomes of neoplastic diseases. Although CD47 upregulation is associated with poor prognosis in several malignancies, the effect of SIRPα expression and its coexpression with CD47 remains unclear. This study aimed to investigate the clinicopathologic effect of CD47 and SIRPα expression in diffuse large B‐cell lymphoma (DLBCL). Immunostaining of 120 biopsy samples showed that CD47 is primarily expressed in tumor cells, whereas SIRPα is expressed in nonneoplastic stromal cells, mostly macrophages. CD47^high cases showed higher MYC protein expression and lower MYC translocation. The SIRPα^high cases presented significantly shorter overall survival (OS) and progression‐free survival (PFS) than SIRPα^low cases in the activated B‐cell (ABC) subtype of DLBCL (P = .04 and P = .02, respectively). Both CD47^high and SIRPα^high presented significantly shorter OS and PFS than other cases among all DLBCL patients (P = .01 and P = .004, respectively), and the ABC type (P = .04 and P = .008, respectively) but not the germinal center B‐cell type. Both CD47^high and SIRPα^high yielded a constant independent prognostic value for OS and PFS in multivariate analysis (hazard ratio [HR], 2.93; 95% confidence interval [CI], 1.20‐7.43; P = .02; and HR, 2.87; 95% CI, 1.42‐5.85; P = .003, respectively). To the best of our knowledge, this is the first study to report that combinatorial CD47 and SIRPα expression is a potential independent prognostic factor for DLBCL. Evaluation of CD47 and SIRPα expression could be useful before CD47 blockade therapy.

Comprehensive immunohistochemical analysis of immune checkpoint molecules in adult T cell leukemia/lymphoma

Acute or lymphomatous type adult T cell leukemia/lymphoma (ATLL) is an aggressive hematopoietic malignancy with poor prognosis. We previously reported that programmed cell death ligand 1 (PD-L1) expression could predict ATLL outcomes. However, the roles of other immune checkpoint molecules remain largely unknown in ATLL. Our aim in this study was to explore the clinicopathological impacts of immune checkpoint molecules in ATLL. Immunohistochemistry was performed in 69 ATLL patients with antibodies against the following: PD-L1, programmed cell death ligand 2 (PD-L2), OX40, OX40 ligand (OX40L), CD137, CD137 ligand (CD137L), Galectin-9, T cell immunoglobulin mucin-3 (Tim-3), cytotoxic T lymphocyte associated protein-4 (CTLA-4), lymphocyte activating-3 (LAG-3), CD80, CD86, glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR), GITR ligand (GITRL), and programmed death-1 (PD-1). Immune checkpoint molecules were variably expressed on neoplastic and/or microenvironmental cells. Expression of PD-1, OX40L, Galectin-9, and PD-L1 was nearly mutually exclusive on neoplastic cells, suggesting that immune checkpoint pathways differ in patients. Microenvironmental expression of PD-L1, OX40L, and Tim-3 was significantly associated with better overall survival (log-rank test; P =0.0004, 0.0394, and 0.0279, respectively). Univariate and multivariate analyses with clinical prognostic factors identified microenvironmental expression of PD-L1 and OX40L, and age (> 70 years) as significant prognostic factors. This is the first comprehensive analysis of ATLL immune checkpoint molecules. Our results may provide information on new therapeutic strategies in ATLL.

Clinicopathological analysis of splenic red pulp low-grade B-cell lymphoma

Primary splenic low-grade B-cell lymphoma of the red pulp comprises hairy cell leukemia (HCL) and splenic B-cell lymphoma/leukemia, unclassifiable (SPLL-U). SPLL-U is a rare disease that includes subtypes of a hairy cell leukemia-variant (HCL-v), splenic diffuse red pulp small B-cell lymphoma (SDRPL) and other types that are known as narrow sense SPLL-U (SPLL-U-NS). Notably, limited information is available regarding the BRAF mutation (V600E) and cyclin D3 expression in subtypes of SPLL-U. Therefore, we performed a pathological analysis of the BRAF mutation (V600E) and characterized pathological features of SPLL-U. We reviewed the pathological findings of 12 SPLL-U cases. The 12 cases considered included two cases of HCL-v, six cases of SPLL-U-NS and four undetermined cases. The BRAF mutation (V600E) was detected in three cases, which were all SPLL-U-NS. Cases with the BRAF mutation (V600E) have increased levels of CD103 expression and decreased cyclin D3 and cyclin D1 expression compared with cases that lacked the BRAF mutation. These findings suggest that the BRAF mutation might play a significant role in SPLL-U. Therefore, the significance of the BRAF mutation should be evaluated via genomic or transcriptional analyses of a large cohort of SPLL-U patients.

High-fat diets provoke phosphorus absorption from the small intestine in rats

OBJECTIVE

The ratio of dietary carbohydrate to fat may affect phosphorus metabolism because both calcium and phosphorus are regulated by similar metabolic mechanisms, and a high-fat diet (HFD) induces deleterious effects on the absorption of dietary calcium. We hypothesized that an HFD induces an increase in phosphorus absorption. The aim of this study was to evaluate the effects of differences in the quantity and quality of dietary fat on phosphorus metabolism over the short- and long-term.

METHODS

Eighteen 8-wk-old Sprague-Dawley male rats were fed an isocaloric diet containing varied ratios of carbohydrates to fat energy and sources of fat (control diet, HFD, and high- saturated fat diet [HF-SFA]). At 3 d and 7 wk after the allocation and initiation of the test diets, feces and urine were collected and used for phosphorus and calcium measurement.

RESULTS

The fecal phosphorous concentration (F-Pi) was lower in the HF-SFA group than in the other two groups; however, the urine phosphorus concentration (U-Pi) was significantly higher in the HF-SFA group than the other two groups when the rats were fed over the short- (P < 0.01) and long -term (P < 0.01 versus control, P < 0.05 versus HFD group). There were no significant differences in type-IIa sodium-phosphate cotransporter (NaPi-2 a) and type-IIc sodium-phosphate cotransporter (NaPi-2 c) mRNA expression, which are renal phosphate transport-related genes; however, the expression of type-IIb sodium-phosphate cotransporter (NaPi-2 b) and type-III sodium-phosphate cotransporter (Pit-1) mRNA in the duodenum was higher in the HFD and HF-SFA groups than in the control group (P < 0.05), although there were no significant differences in these in the jejunum.

CONCLUSIONS

The present results indicated that an HFD, particularly HF-SFA, increases intestinal phosphate absorption compared with control.

Certified Reference Material for Analytical Quality Assurance of Minor and Trace Elements in Food and Related Matrixes Based on a Typical Japanese Diet: Interlaboratory Study

A Certified Reference Material (CRM) was prepared at the National Institute for Environmental Studies (NIES), Japan, in collaboration with the National Institute of Radiological Sciences (NIRS), Japan, for the analytical quality assurance of minor and trace elements in food and related matrixes. The starting material for the CRM was all food served in 29 households in Japan over two 3-day periods in 1997–1998, and thus the CRM represented a typical Japanese diet. All foods (meals, snacks, and beverages) were homogenized, freeze-dried, pulverized, blended, dispensed into 1100 bottles, and sterilized. The within- and between-bottle homogeneity of the prepared CRM was satisfactory for most of the elements. The concentrations of 14 elements (Na, Mg, K, Ca, Mn, Cu, Zn, As, Se, Sr, Cd, Sn, Ba, and U) were certified based on a collaborative analysis involving NIES, NIRS, and 20 other laboratories. Reference values were given for the concentrations of 12 additional elements (P, Cl, Fe, Co, Ni, Br, Rb, Mo, I, Cs, Pb, and Th). The elements certified and those given reference values include minerals, essential trace elements, contaminant elements, and long-lived radionuclides. Thus, this CRM is of practical value in the quality assurance of element analysis of foods and diets in nutritional, environmental, and radiological research.

Metagenome-wide association study of gut microbiome revealed novel aetiology of rheumatoid arthritis in the Japanese population

Objective

The causality and pathogenic mechanism of microbiome composition remain elusive in many diseases, including autoimmune diseases such as rheumatoid arthritis (RA). This study aimed to elucidate gut microbiome’s role in RA pathology by a comprehensive metagenome-wide association study (MWAS).

Methods

We conducted MWAS of the RA gut microbiome in the Japanese population (n_case=82, n_control=42) by using whole-genome shotgun sequencing of high depth (average 13 Gb per sample). Our MWAS consisted of three major bioinformatic analytic pipelines (phylogenetic analysis, functional gene analysis and pathway analysis).

Results

Phylogenetic case–control association tests showed high abundance of multiple species belonging to the genus Prevotella (e.g., Prevotella denticola) in the RA case metagenome. The non-linear machine learning method efficiently deconvoluted the case–control phylogenetic discrepancy. Gene functional assessments showed that the abundance of one redox reaction-related gene (R6FCZ7) was significantly decreased in the RA metagenome compared with controls. A variety of biological pathways including those related to metabolism (e.g., fatty acid biosynthesis and glycosaminoglycan degradation) were enriched in the case–control comparison. A population-specific link between the metagenome and host genome was identified by comparing biological pathway enrichment between the RA metagenome and the RA genome-wide association study results. No apparent discrepancy in alpha or beta diversities of metagenome was found between RA cases and controls.

Conclusion

Our shotgun sequencing-based MWAS highlights a novel link among the gut microbiome, host genome and pathology of RA, which contributes to our understanding of the microbiome’s role in RA aetiology.

[Clinical features of adult-onset chronic active Epstein-Barr virus infection]

Chronic active Epstein-Barr virus infection (CAEBV) presents with mononucleosis-like symptoms such as chronic persistent or recurrent pyrexia, lymphadenopathy, and hepatosplenomegaly because of the reactivation of Epstein-Barr virus (EBV) as demonstrated by the recurrence of EBV-infected cells. The mechanism of CAEBV remains obscure, and CAEBV can lead to fatal conditions such as hemophagocytic syndrome and malignant lymphoma by clonal expansion of EBV-infected T- or NK-cells. Without hematopoietic stem cell transplantation, CAEBV has a poor prognosis. CAEBV is listed in the revised 2016 World Health Organization classification as a chronic active EBV infection of T- and NK-cell types, systemic form, among EBV-positive T- and NK-cell lymphoproliferative diseases of childhood. However, similar clinical conditions have been reported in adult patients. Therefore, we investigated the clinical features of adult patients with CAEBV-like features (adult-onset CAEBV) in a relatively small number of cases. Additionally, genetic alterations related to CAEBV development have also been reported. Along with these results, we reviewed the clinical characteristics of adult-onset CAEBV.

Transient severe conduction disturbances associated with ankylosing spondylitis

A 46-year-old man presented with advanced and complete atrioventricular block. He was diagnosed with human leukocyte antigen-B27-positive ankylosing spondylitis (AS) and treated with nonsteroidal anti-inflammatory drugs for AS. The severe atrioventricular block spontaneously improved and resolved after 3 months of therapy. Sequential cardiac magnetic resonance imaging demonstrated transient myocardial high-intensity signals in the basal septum close to the membranous portion of the septum. A pacemaker was not needed because of the reversible atrioventricular block.

Anaplastic large cell lymphoma, with 1,25(OH)2D3-mediated hypercalcemia: A case report

Hypercalcemia due to malignant tumors including malignant lymphomas is relatively common. Among cancer patients with hypercalcemia, humoral hypercalcemia of malignancy is the most common and accounts for about 80% of all cases with hypercalcemia. 1,25-dihydroxyvitamin D_³(1,25(OH)_²D_³)-mediated hypercalcemia is relatively rare. Although malignant lymphoma has been also reported to cause 1,25(OH)_²D_³-mediated hypercalcemia, it is not known whether there is any association between 1,25(OH)_²D_³-mediated hypercalcemia and any specific histological type of malignant lymphoma. We herein report a case of an anaplastic large cell lymphoma (ALCL), anaplastic lymphoma kinase (ALK) -negative with 1,25(OH)_²D_³-mediated hypercalcemia, which has never been previously reported. An 80-year-old Japanese man was admitted to our department due to acute exacerbation of hypercalcemia. He was diagnosed with ALCL, ALK-negative. Serum 1,25(OH)_²D_³ level was high and seemed to be associated with the lymphoma because the serum calcium and 1,25(OH)_²D_³ levels improved in response to chemotherapy. Histological findings showed that many CD68 positive macrophages were observed in the microenvironment of tumor cells. Lymphoma cells or tumor microenvironmental cells may produce 1,25(OH)_²D_³ because several previous reports showed the source of 1,25(OH)_²D_³ can be either lymphoma or tumor microenvironmental cells. Moreover, because 1,25(OH)_²D_³-mediated hypercalcemia has been reported regardless of the specific histological type of lymphoma, tumor microenvironmental cells may be involved in this condition. However, we could not identify the source of 1,25(OH)_²D_³ in this case. The association between 1,25(OH)_²D_³ production and prognosis in malignant lymphomas is yet unknown; further studies are needed to elucidate the clinical characteristics of malignant lymphoma with 1,25(OH)_²D_³-mediated hypercalcemia.

Gemcitabine, Dexamethasone, and Cisplatin Regimen as an Effective Salvage Therapy for High-grade B-cell Lymphoma with MYC and BCL2 and/or BCL6 Rearrangements

A 61-year-old woman exhibited right inguinal lymphadenopathy and right lower limb edema approximately 1 month prior to hospitalization. She was diagnosed with high grade B-cell lymphoma, and a lymph node biopsy and fluorescence in situ hybridization indicated MYC, BCL2, and BCL6 rearrangements (triple-hit lymphoma). She had progressive disease that was CD20-negative after two courses of rituximab, cyclophosphamide, doxorubicin, vincristine, methotrexate/ifosfamide, etoposide, high-dose cytarabine (R-CODOX-M/IVAC) therapy. Subsequent etoposide, prednisolone, vincristine, cyclophosphamide, doxorubicin (EPOCH) therapy was not effective. However, after two cycles of gemcitabine, dexamethasone, and cisplatin (GDP) therapy, she achieved a complete response and was able to undergo autologous peripheral blood stem cell transplantation. GDP therapy may be effective as salvage therapy for chemotherapy-resistant triple-hit lymphoma.

Analysis of GNA13 Protein in Follicular Lymphoma and its Association With Poor Prognosis

GNA13 is a G protein involved in modulating tumor proliferative capacity, infiltration, metastasis, and migration. Genomic alteration of GNA13 was frequently observed in follicular lymphoma (FL). In this study, we examined 167 cases of FL by immunostaining of GNA13 using tissue microarray to evaluate the clinical significance. There were 26 GNA13-positive cases (15.6%) and 141 GNA13-negative cases (84.4%). GNA13-positive cases had a higher incidence of early progression of disease for which disease progression was recognized within 2 years compared with GNA13-negative cases (P=0.03). There were no significant differences in other clinicopathologic factors including histological grade, BCL2-IGH translocation, immunohistochemical phenotype, and Follicular Lymphoma International Prognostic Index. In addition, overall survival and progression-free survival were poorer in GNA13-positive cases than in GNA13-negative cases (P=0.009 and 0.005, respectively). In multivariate analysis, GNA13 positivity was found to be a poor prognostic factor for overall survival and progression-free survival. Thus, GNA13 protein expression was an independent prognostic factor and may affect disease progression in FL.

Epidemiology and secular trends of malignant lymphoma in Japan: Analysis of 9426 cases according to the World Health Organization classification

This study provides an overview of the epidemiology and secular trends of malignant lymphoma in Japan. Using data from clinics and hospitals throughout Japan, we analyzed 9426 cases of malignant lymphoma diagnosed in 2007‐2014. We show that the proportion of follicular lymphoma and methotrexate‐associated lymphoproliferative disorder increased during this time, as did the onset age for follicular lymphoma and diffuse large B‐cell lymphoma. Significant increases in onset age for follicular lymphoma and diffuse large B‐cell lymphoma were observed in both men and women (all P values <0.0001 except for P = 0.0448 for the latter disease in women). Further studies are required to determine the reasons for the higher proportion of and onset age for these lymphomas. Additionally, we believe that continued observation of these trends is necessary.

Cladribine treatment for Erdheim-Chester disease involving the central nervous system and concomitant polycythemia vera: A case report

Erdheim–Chester disease (ECD), a rare form of non-Langerhans cell histiocytosis, is characterized by the infiltration of foamy CD68⁺ and CD1a^- histiocytes into multiple organ systems. Central nervous system (CNS) involvement has recently been reported to be a poor prognostic factor when treating ECD with interferon alpha. We report the case of a 66-year-old Japanese patient with ECD involving the CNS who harbored the BRAF V600E mutation and also concomitantly developed polycythemia vera with the JAK2 V617F mutation. We confirmed 2-chlorodeoxyadenosine (cladribine) therapy to be effective for the patient in this case.

Strategic Isolation of a Polyoxocation Mimicking Vanadium(V) Oxide Layered-Structure by Stacking of [H2V2O8]4- Anions Bridged by (1,4,7-Triazacyclononane)Co(III) Complexes

An isolation of a vanadium(V) oxide cluster mimicking V₂O₅ layered structure was achieved formulated as [{Co(tacn)}₄V₄O₁₂(OH)₄]⁴⁺ (1) (tacn = 1,4,7-triazacyclononane). From the ⁵¹V NMR spectra of the reaction mixtures, we optimized the reaction condition in terms of a molar ratio of VO₄^3- and [Co(tacn)(H₂O)₃]³⁺ as well as a pH value. Cluster 1 is stable in a wide range of pH values from 1.5 to 8.0, and the presence of multiple hydrogen bondings in the structure is a unique feature. In the X-ray analysis of cluster 1, the V⋯ V distances are classified into two groups of relatively shorter distances (2.978(1) Å) and longer interactions (3.554(1) Å), and it is a good model of the substructure of V₂O₅ bulk material. As far as we know, this is a first example of an isolation of mixed-metal cluster including a unit of V₂O₅ structure by a stack of two layers of [H₂V₂O₈]^4-, although cubic V₄O₄ cubane-type clusters are well known. The solid sample of compound 1-Cl and 1-Br shows reversible thermochromic behavior accompanied by crystal to amorphous transformation upon hydration-dehydration process.

Synthesis of cationic molybdenum-cobalt heterometallic clusters protected against hydrolysis by macrocyclic triazacyclononane complexes

Four kinds of cobalt-polyoxomolybdenum clusters were synthesized by a combination of polyoxomolybdates and a Co-tacn (tacn = 1,4,7-triazacyclononane) complex. The heterometallic polynuclear clusters were obtained by the reaction of Na2MoO4 and [Co(tacn)(H2O)3](CF3SO3)3·H2O in water. The peripherals of polyoxomolybdates are capped by thermodynamically stable [Co(tacn)]3+ protecting groups to prevent further hydrolysis and condensation reactions. Intra-molecular hydrogen bonds between N-H groups on tacn and oxygen atoms on the molybdate core contribute to the stability of the complexes in water. Under the optimized synthetic conditions, the molar ratios of Na2MoO4 and [Co(tacn)(H2O)3](CF3SO3)3·H2O were adjusted to 1 : 0.3, 1 : 0.9, or 1 : 1.5, producing [{Co(tacn)}2Mo3O12]·2NaCF3SO3·7H2O (1), [{Co(tacn)}4H2Mo7O27](CF3SO3)2·13H2O (2), and [{Co(tacn)}4H3Mo4O17](CF3SO3)5·6H2O (3), respectively. As one of the most important factors, the adjustments of the pH values by changing the molar ratio enabled us to isolate these clusters. The presence of pyridine produces a neutral complex, [Co2(tacn)2(pyridine)Mo5O18]·4.5H2O (4) containing a lacunary Lindqvist-type polyoxomolybdate. The synthesis of complexes 2-4 is also possible starting from cluster 1, implying that 1 is a precursor for the formation of 2-4 in aqueous solution. Complexes 2-4 have a common structural building block, [{Co(tacn)}2Mo3O13], in each of the cluster units. The 1H NMR spectra of 2 and 3 in aqueous solution show multiple splitting patterns of methylene signals on tacn ligands according to the chemical environments indicated by the crystallographic structure. The 59Co NMR spectrum of cluster 3 in CH3NO2 has two signals from two different Co units with a 3 : 1 integration ratio ensuring the structural integrity in solution. The broadening of one of the signals for the 59Co NMR spectrum of cluster 3 in water as a protic solvent reveals the presence of the deprotonation equilibrium of the acidic protons on the cluster framework in water.

A case of chronic lymphocytic leukemia complicated by autoimmune hemolytic anemia due to ibrutinib treatment

Ibrutinib (IBR) covalently binds to the active site of Bruton's tyrosine kinase (BTK) and is used for the treatment of relapsed/refractory chronic lymphocytic leukemia (CLL). Approximately 5-10% of CLL is complicated by autoimmune cytopenia (AIC), such as autoimmune hemolytic anemia (AIHA). Several cases of AIC have reportedly demonstrated improvement during IBR treatment. However, in our case, the patient developed AIHA during oral IBR treatment. As AIHA is exacerbated by the increased number of CLL cells in the peripheral blood, it may have developed because of disease progression rather than IBR use. This phenomenon may also be attributed to the production of autoantibodies due to increased number of CD5+ B cells. In this case, withdrawal of IBR and administration of rituximab improved hemolysis. If AIHA develops during treatment, its etiology must be examined to confirm the effects of treatment.

Expression of programmed death ligand 1 is associated with poor prognosis in myeloid sarcoma patients

Myeloid sarcoma (MS) is a rare condition and is an extramedullary tumour of immature myeloid cells. It is now known that the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) pathway suppresses the host antitumor responses and that these products are expressed on both tumour cells and tumour-infiltrating cells in various malignancies. However, little is known about the significance of PD-1/PD-L1 expression on tumour cells and tumour microenvironmental cells in MS. To investigate the clinicopathological significance of PD-1/PD-L1 expression in MS, we analyzed 98 patients by immunohistochemistry. Of these, 10.2% of cases had neoplastic tumour cells positive for PD-L1 (nPD-L1⁺ ). However, the rate of nPD-L1⁺ was <5% (range: 0.27 to 2.97%). On the other hand, PD-L1 expression on 1 or more of stromal cells in the tumour microenvironment (miPD-L1⁺ ) was observed in 37.8% of cases. Because all nPD-L1⁺ cases expressed PD-1 on less than 5% of tumour cells, we compared the miPD-L1⁺ and miPD-L1^- groups. There was a correlation between miPD-L1⁺ status and the number of PD-1-expressing tumour -infiltrating lymphocytes (PD-1⁺ TILs; P = .0229). miPD-L1⁺ was found to be associated with poorer overall survival and progression-free survival (P = .00392, P = .00261, respectively). Multivariate analysis also confirmed miPD-L1⁺ to be an independent poor prognostic factor. In conclusion, our study indicated that the immunotherapy blocking the PD-1/PD-L1 pathway may improve the clinical outcome of MS.

The competing effects of microbially derived polymeric and low molecular-weight substances on the dispersibility of CeO2 nanoparticles

To understand the competing effects of the components in extracellular substances (ES), polymeric substances (PS) and low-molecular-weight small substances (SS) <1 kDa derived from microorganisms, on the colloidal stability of cerium dioxide nanoparticles (CeNPs), we investigated their adsorption to sparingly soluble CeNPs at room temperature at pH 6.0. The ES was extracted from the fungus S. cerevisiae. The polypeptides and phosphates in all components preferentially adsorbed onto the CeNPs. The zeta potentials of ES + CeNPs, PS + CeNPs, and SS + CeNPs overlapped on the plot of PS itself, indicating the surface charge of the polymeric substances controls the zeta potentials. The sizes of the CeNP aggregates, 100-1300 nm, were constrained by the zeta potentials. The steric barrier derived from the polymers, even in SS, enhanced the CeNP dispersibility at pH 1.5-10. Consequently, the PS and SS had similar effects on modifying the CeNP surfaces. The adsorption of ES, which contains PS + SS, can suppress the aggregation of CeNPs over a wider pH range than that for PS only. The present study addresses the non-negligible effects of small-sized molecules derived from microbial activity on the migration of CeNP in aquatic environments, especially where bacterial consortia prevail.

Expression pattern of immunosurveillance-related antigen in adult T cell leukaemia/lymphoma

AIMS

Adult T cell leukaemia/lymphoma (ATLL) is an aggressive malignancy with a poor prognosis. Human leucocyte antigen (HLA) and β2 microglobulin (β2M) serve as key molecules in tumour immunity, and their expression is reduced frequently in tumour cells. Programmed cell death (PD)-1/PD-ligand1 (PD-L1) interactions play a role in escape of tumour cells from T cell immunity. Therefore, this study aimed to determine the clinicopathological relevance of HLA and β2M expressions in ATLL cells and PD-L1 expression in lymphoma or stromal cells and predict the overall survival of patients with ATLL.

METHODS AND RESULTS

We analysed a total of 123 biopsy samples from patients newly diagnosed with ATLL by using immunohistochemical analysis. Of the patients enrolled, 91 (74%) were positive for HLA (in cell membrane, 60 patients), 89 (72%) were positive for β2M (in cell membrane, 54 patients) and 48 (39%) were positive for both HLA and β2M in the cell membrane (HLA^m+ β2M^m+ ). No significant clinical differences other than prognosis were found between the HLA^m+ β2M^m+ group and the other groups. Immunophenotypical evaluation revealed significantly higher rates of CD30-positive lymphoma cells (P = 0.003) and PD-L1-positive stromal cells in microenvironments (miPD-L1^high ) (P = 0.011) of the HLA^m+ β2M^m+ group than in the other groups. The HLA^m+ β2M^m+ group had a significantly better prognosis that the other groups (P = 0.0096), and patients showing HLA^m+ β2M^m+ with miPD-L1^high had the most favourable prognosis among all groups.

CONCLUSIONS

The membranous expression of HLA and β2M is likely to reflect the immune response and would be useful to predict prognosis before starting ATLL therapy.

A distinct subtype of Epstein-Barr virus-positive T/NK-cell lymphoproliferative disorder: adult patients with chronic active Epstein-Barr virus infection-like features

The characteristics of adult patients with chronic active Epstein-Barr virus infection are poorly recognized, hindering early diagnosis and an improved prognosis. We studied 54 patients with adult-onset chronic active Epstein-Barr virus infection diagnosed between 2005 and 2015. Adult onset was defined as an estimated age of onset of 15 years or older. To characterize the clinical features of these adults, we compared them to those of 75 pediatric cases (estimated age of onset <15 years). We compared the prognosis of adult-onset chronic active Epstein-Barr virus infection with that of patients with nasal-type (n=37) and non-nasal-type (n=45) extranodal NK/T-cell lymphoma. The median estimated age of onset of these lymphomas was 39 years (range, 16–86 years). Compared to patients with pediatric-onset disease, those in whom the chronic active Epstein-Barr virus infection developed in adulthood had a significantly decreased incidence of fever (P=0.005), but greater frequency of skin lesions (P<0.001). Moreover, hypersensitivity to mosquito bites and the occurrence of hydroa vacciniforme were less frequent in patients with adult-onset disease (P<0.001 and P=0.0238, respectively). Thrombocytopenia, high Epstein-Barr virus nuclear antigen antibody titer, and the presence of hemophagocytic syndrome were associated with a poor prognosis (P=0.0087, P=0.0236, and P=0.0149, respectively). Allogeneic hematopoietic stem cell transplantation may improve survival (P=0.0289). Compared to pediatric-onset chronic active Epstein-Barr virus infection and extranodal NK/T-cell lymphoma, adult-onset chronic active Epstein-Barr virus infection had a poorer prognosis (P<0.001 and P=0.0484, respectively). Chronic active Epstein-Barr virus infection can develop in a wide age range, with clinical differences between adult-onset and pediatric-onset disease. Adult-onset chronic active Epstein-Barr virus infection is a disease with a poor prognosis. Further research will be needed.

Prognostic factors for histiocytic and dendritic cell neoplasms

Histiocytic and dendritic cell neoplasms are rare and poorly studied. We report the clinical characteristics and prognostic factors in such cases in Japan. We investigated the clinical characteristics and survival in 87 adult patients with histiocytic and dendritic cell neoplasms. Fifty patients had histiocytic sarcoma, 12 had Langerhans cell histiocytosis, 11 had follicular dendritic cell sarcoma, 8 had Langerhans cell sarcoma, 6 had interdigitating cell sarcoma and 1 had indeterminate dendritic cell sarcoma. The median follow-up period was 18.0 (range: 9.6-71.8) months, and median overall survival (OS) was 23.5 months. The 2-year OS rate was 49.2%. In the multivariate analysis, elevated lactate dehydrogenase (LDH) (p =.004), ECOG performance status (PS) 2-4 (p =.006), and Ann Arbor stage III-IV (p =.008) affected OS. Stratification by elevated LDH, ECOG PS 2-4, and Ann Arbor stage III-IV allowed classification of patients into low risk, intermediate risk, and high risk groups. The same classification was applicable for HS and non-HS categories. In the rare neoplasms of histiocytic and dendritic cell sarcoma, ECOG PS, Ann Arbor stage, and LDH are important prognostic factors for predicting survival.

Clinicopathological features of primary splenic follicular lymphoma

Follicular lymphoma (FL) is a low-grade lymphoma that is usually characterized by generalized lymphadenopathy. Extranodal invasion by FL generally involves the bone marrow, skin, and duodenum; splenic infiltration often occurs in the advanced stages. However, primary splenic FL is very rare. Hence, few studies have been performed on splenic FL, and its clinicopathological features have not been established. This study aimed to investigate the clinicopathological features of primary splenic FL, as compared to nodal FL. We analyzed 17 patients diagnosed with primary splenic FL and 153 control patients with systemic FL. Hepatitis C virus (HCV)-positive status was significantly more common in patients with splenic FL than in the control patients (p = 0.02). Ann Arbor stage III or IV (p = 0.0003) and high-risk FLIPI (Follicular Lymphoma International Prognostic Index) (p = 0.03) were significantly less common in patients with splenic FL than in the control patients; however, the overall and progression-free survival curves were not significantly different between the groups. Among the 17 patients with splenic FL, the progression-free survival was significantly worse in patients who underwent splenectomy without receiving postoperative chemotherapy than in those who did (p = 0.03). These results suggest that primary splenic FL should be considered different from systemic FL; accordingly, its management should also be conducted differently.

Peripheral T-cell lymphoma, not otherwise specified: a retrospective single-center analysis

We retrospectively analyzed clinical and pathological features, treatments, and prognoses in 28 patients with newly diagnosed peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) in Niigata University Medical and Dental Hospital. Of them, 16 were males and 12 were females, and their median age was 62.5 (range, 26-88) years. The International Prognostic Index was high-intermediate/high in 68% of patients. Twelve patients were treated with CHOP/THP-COP and nine with third-generation chemotherapy regimens. At a median follow-up period of 30 (range: 1-164) months, the 2-year overall survival and progression-free survival rates were 61% and 44%, respectively. Further investigation of novel agents for treating PTCL-NOS is warranted.

Clinicopathological features of cryptococcal lymphadenitis and a review of literature

Cryptococcosis is an invasive fungal infection in immunocompromised patients. The clinicopathological characteristics of cryptococcal lymphadenitis are not well known. We analyzed three cases of cryptococcal lymphadenitis and compared their characteristics with those in previous reports. Two patients were human immunodeficiency virus (HIV) carriers, and one patient was a human T-cell leukemia virus type-1 (HTLV-1) carrier. The age of the HTLV-1 carrier with cryptococcosis was much higher than that of the HIV-1 carriers. CD4-positive cell counts in peripheral blood were 5.8/μL (Case 1) and 79.9/μL (Case 2) in the HIV carriers and 3285/μL in the HTLV-1 carrier (Case 3). According to flow cytometric analysis of the lymph nodes of Cases 1, 2, and 3, 50.0%, 87.1%, and 85.9%, respectively, of the T-cells were CD3; 9.8%, 16.3%, and 75.8%, respectively, were CD4; and 35.5%, 77.3%, and 10.2%, respectively, were CD8. Cryptococcus neoformans was detected in tissue culture in all patients. Although gelatinous lesions and numerous fungal cocci were observed in the two HIV patients, the granuloma formation was small. Gelatinous formation and granuloma formation were observed in the HTLV-1 carrier. Necrosis was observed in all cases. In previous reports, granuloma formation, epithelioid cells, and necrotic lesions were observed in most cases. Most of the patients were also immunosuppressed. However, no HTLV-1 carrier was detected. In conclusion, lymphadenopathy in a HTLV-1 carrier may suggest the presence of cryptococcal lymphadenitis. The frequency of cryptococcosis in HTVL-1 carriers may increase with increase in the long-term survival rate of HTLV-1 carriers.

Novel small molecule inhibiting CDCP1-PKCδ pathway reduces tumor metastasis and proliferation

CUB domain‐containing protein‐1 (CDCP1) is a trans‐membrane protein predominantly expressed in various cancer cells and involved in tumor progression. CDCP1 is phosphorylated at tyrosine residues in the intracellular domain by Src family kinases and recruits PKCδ to the plasma membrane through tyrosine phosphorylation‐dependent association with the C2 domain of PKCδ, which in turn induces a survival signal in an anchorage‐independent condition. In this study, we used our cell‐free screening system to identify a small compound, glycoconjugated palladium complex (Pd‐Oqn), which significantly inhibited the interaction between the C2 domain of PKCδ and phosphorylated CDCP1. Immunoprecipitation assays demonstrated that Pd‐Oqn hindered the intercellular interaction of phosphorylated CDCP1 with PKCδ and also suppressed the phosphorylation of PKCδ but not that of ERK or AKT. In addition, Pd‐Oqn inhibited the colony formation of gastric adenocarcinoma 44As3 cells in soft agar as well as their invasion. In mouse models, Pd‐Oqn markedly reduced the peritoneal dissemination of gastric adenocarcinoma cells and the tumor growth of pancreatic cancer orthotopic xenografts. These results suggest that the novel compound Pd‐Oqn reduces tumor metastasis and growth by inhibiting the association between CDCP1 and PKCδ, thus potentially representing a promising candidate among therapeutic reagents targeting protein–protein interaction.