Isaya Hashimoto

High-Level Expression of Chemokine CXCL16 by Tumor Cells Correlates with a Good Prognosis and Increased Tumor-Infiltrating Lymphocytes in Colorectal Cancer

CXCL16 is a new member of the chemokine superfamily, which exists in a transmembrane as well as a soluble form. Its receptor CXCR6 is detected on CD4(+) T cells, CD8(+) T cells, and natural killer T cells. Here, we report a significant correlation of CXCL16 expression by tumor cells with the infiltration of T cells and prognosis in colorectal cancer (CRC). We first found that CXCL16 expression was consistently up-regulated more in tumor tissues than in normal mucosa derived from the same CRC patients. Four human CRC cell lines also expressed CXCL16 mRNA and secreted soluble CXCL16. We next examined the expression of CXCL16 and infiltration of lymphocytes in CRC specimens (n = 58) by immunohistochemistry. CRC patients with high levels of CXCL16 expression (n = 43) had higher levels of CD4(+) and CD8(+) tumor-infiltrating lymphocytes (TIL; P < 0.01) than those with low levels of CXCL16 expression (n = 15). Furthermore, the high CXCL16 expression group showed significantly better prognosis than the low CXCL16 expression group (P < 0.05). Collectively, our data suggest that the expression of CXCL16 by tumor cells enhances the recruitment of TILs, thereby bringing about a better prognosis in CRC. Thus, CXCL16 is a new prognostic biomarker and may be useful for the development of a more effective therapeutic strategy for CRC.

Blocking on the CXCR4/mTOR signalling pathway induces the anti-metastatic properties and autophagic cell death in peritoneal disseminated gastric cancer cells

Patients with advanced gastric carcinoma, especially peritoneal dissemination, have a poor prognosis even after any treatment. Chemokines are now known to play an important role in cancer growth and metastasis. We recently reported that the chemokine CXCL12 plays an important role in the development of peritoneal carcinomatosis from gastric carcinoma. In this study, we investigated signalling pathway involved in the peritoneal carcinomatosis induced by chemokine CXCL12. Akt was rapidly and strongly phosphorylated by chemokine CXCL12. CXCL12 also induced the activation of p70S6K (S6K) and eukaryotic initiation factor 4E binding protein 1 (4E-BP1) included in mammalian target of rapamycin (mTOR) pathways which are located downstream of Akt, resulting in enhancements of metastatic properties such as MMP production, cell migration and cell growth in peritoneal disseminated gastric cancer, NUGC4 cells. Furthermore, mTOR inhibitor rapamycin not only drastically inhibited migration and MMP production, but also induced type II programmed cell death, autophagic cell death. In the present study, we have shown for the first time that the mTOR pathway plays a central role in the development of peritoneal carcinomatosis, and blocking this pathway induces autophagic cell death in disseminated gastric cancer. Therefore, blocking on the CXCR4/mTOR signalling pathway may be useful for the future development of a more effective therapeutic strategy for gastric cancer involved in peritoneal dissemination.

CXCL16 suppresses liver metastasis of colorectal cancer by promoting TNF-α-induced apoptosis by tumor-associated macrophages

BackgroundInhibition of metastasis through upregulation of immune surveillance is a major purpose of chemokine gene therapy. In this study, we focused on a membrane-bound chemokine CXCL16, which has shown a correlation with a good prognosis for colorectal cancer (CRC) patients.MethodsWe generated a CXCL16-expressing metastatic CRC cell line and identified changes in TNF and apoptosis-related factors. To investigate the effect of CXCL16 on colorectal liver metastasis, we injected SL4-Cont and SL4-CXCL16 cells into intraportal vein in C57BL/6 mice and evaluated the metastasis. Moreover, we analyzed metastatic liver tissues using flow cytometry whether CXCL16 expression regulates the infiltration of M1 macrophages.ResultsCXCL16 expression enhanced TNF-α-induced apoptosis through activation of PARP and the caspase-3-mediated apoptotic pathway and through inactivation of the NF-κB-mediated survival pathway. Several genes were changed by CXCL16 expression, but we focused on IRF8, which is a regulator of apoptosis and the metastatic phenotype. We confirmed CXCL16 expression in SL4-CXCL16 cells and the correlation between CXCL16 and IRF8. Silencing of IRF8 significantly decreased TNF-α-induced apoptosis. Liver metastasis of SL4-CXCL16 cells was also inhibited by TNF-α-induced apoptosis through the induction of M1 macrophages, which released TNF-α. Our findings suggest that the accumulation of M1 macrophages and the enhancement of apoptosis by CXCL16 might be an effective dual approach against CRC liver metastasis.ConclusionsCollectively, this study revealed that CXCL16 regulates immune surveillance and cell signaling. Therefore, we provide the first evidence of CXCL16 serving as an intracellular signaling molecule.

Therapeutics target of CXCR4 and its downstream in peritoneal carcinomatosis of gastric cancer.

Patients with advanced gastric carcinoma, especially peritoneal dissemination, have a poor prognosis. Various treatments have been used for peritoneal dissemination of gastric cancer, but there is no effective therapy for this condition. At present, similar proprieties of chemokines between trafficking of leukocytes during immune and inflammatory reactions and organ selective migration of cancer cells during metastasis are widely recognized. In particular, chemokine CXCL12 and its receptors CXCR4 are now known to play an important role in cancer progression. Recently, we reported for the first time that CXCR4 and its ligand, CXCL12, were involved in the development of peritoneal carcinomatosis of gastric cancer, and additionally, clarified the molecular mechanisms of the cell signaling pathways by which gastric cancer develops metastatic ability via CXCR4 and mTOR. In this review, we focus on the biological functions of chemokine receptors, particularly CXCR4 expressed on gastric cancer cells, and the therapeutic strategies targeting CXCR4-mediating signaling pathways in peritoneal carcinomatosis.

Anti-tumor effect of combining CC chemokine 22 and an anti-CD25 antibody on myeloma cells implanted subcutaneously into mice.

Chemokines are known to have anti-tumor effects due to their chemoattractant properties, which stimulate the accumulation of infiltrating immune cells in tumors. CCL22 (macrophage-derived chemokine, MDC) attracts killer T?cells, helper T cells and antigen-presenting cells expressing the CCL22 receptor, CCR4. Thus, CCL22 gene expression results in the accumulation of these cells in tumors, and has been shown to suppress lung and colon cancer growth in mice. In the present study, early-stage subcutaneous tumor growth in a mouse multiple myeloma cell line stably expressing CCL22 (MPC-CCL22) was decreased compared to tumor growth in control cells (MPC-mock). However, the final extent of tumor growth in these cell lines was almost equivalent. Regulatory T cells, which express CD25, CD4 and CCR4, are known to cause immune disruption. We therefore investigated the association of regulatory T cells with the progressive decrease in CCL22 anti-tumor effect observed in late-stage experimental multiple myelomas. Tumor growth in MPC-CCL22 cells was observed to drastically decrease, to the point of complete tumor regression, when CD4 or CD25 T cells were depleted. Here, we document the drastic anti-tumor effect of a combination of CCL22 and anti-CD25 antibody on multiple myeloma cells.

Prognostic significance of KLF4 expression in gastric cancer

To understand the roles of pluripotent stem cell-inducing genes in gastric cancer, the expression of Krüppel-like factor 4 (KLF4), Nanog, octamer-binding transcription factor 4 (Oct4), avian myelocytomatosis viral oncogene homolog (c-Myc) and sex-determining region Y-box 2 (SOX2) was examined using the newly developed gastric carcinoma tissue microarray. The associations between the immunohistochemical expression levels of the pluripotency-inducing factors and the clinicopathological data of 108 patients with gastric cancer were analyzed. No associations were identified between the expression levels of the five pluripotency-inducing factors and the tumor-node-metastasis (TNM) classification or clinicopathological characteristics of the patients. In addition, multivariate analysis revealed no association of Nanog, Oct4, SOX2 or c-Myc with the prognosis of the gastric cancer patients; however, low expression of KLF4 was determined to be an independent negative prognostic factor (P=0.0331), particularly in patients who underwent R0 resection (TNM stages 2 and 3; P=0.0048). In summary, low KLF4 expression was found to be negatively associated with overall survival, and may therefore be a useful prognostic marker in gastric cancer patients.

A patient with paroxysmal nocturnal hemoglobinuria being treated with eculizumab who underwent laparoscopic cholecystectomy: report of a case

Paroxysmal nocturnal hemoglobinuria (PNH) is acquired hemolytic anemia characterized by symptoms such as anemia and hemoglobinuria. In recent years, eculizumab as an anti-complement (C5) monoclonal antibody has been used for PNH and shown to have marked effects. We performed laparoscopic cholecystectomy in a patient with PNH being treated with eculizumab, and could avoid the risk of perioperative hemolysis and thrombosis. [Patient] The patient was a 48-year-old female who had developed PNH when she was 39 years old. At the age of 46 years, eculizumab administration was initiated once every 2 weeks. During the administration period, neither the progression of anemia nor hemoglobinuria was observed. In March 2013, gallstones were detected, and she was referred to our hospital for surgery. Eculizumab was administered 10 days before surgery, and laparoscopic cholecystectomy was performed in May 2013. After the operation, for the prevention of thrombosis, elastic stockings and a foot pump were used without anticoagulant administration. After the operation, neither the progression of anemia nor hemoglobinuria was observed. On postoperative day 5, eculizumab was administered as planned, and she showed a favorable general condition and was discharged. [Discussion] Perioperative care in PNH patients was conventionally considered to involve a high risk of developing anemia, thrombosis, or infection. However, after the advent of eculizumab, the control of the symptoms of PNH became possible in many patients. In this patient with PNH being treated with eculizumab, safe perioperative management was possible without the development of complications.

The expression of microRNA 574-3p as a predictor of postoperative outcome in patients with esophageal squamous cell carcinoma.

BackgroundDespite advances in radical esophagectomies and adjuvant therapy, the postoperative prognosis in esophageal squamous cell carcinoma (ESCC) patients remains poor. The aim of this study was to identify a molecular signature to predict postoperative favorable outcomes in patients with ESCC.MethodsAs a training data set, total RNA was extracted from formalin-fixed paraffin-embedded samples of surgically removed specimens from 19 ESCC patients who underwent curative esophagectomy. The expression of microRNA (miRNA) was detected using a miRNA oligo chip on which 885 genes were mounted. As a validation data set, we obtained frozen samples of surgically resected tumors from 12 independent ESCC patients and the expression of miR-574-3p was detected by quantitative real-time PCR.ResultsOur microarray analysis in the training set patients identified three miRNAs (miR-574-3p, miR-106b, and miR-1303) and five miRNAs (miR-1203, miR-1909, miR-204, miR-371-3p, miR-886-3p) which were differentially expressed between the patients with (n = 14) and without (n = 5) postoperative tumor relapse (p < 0.01 and p < 0.05, respectively). Higher expression of miR-574-3p, which showed the most significant association with non-relapse (p = 0.001), was associated with favorable overall survival (p = 0.016). Real-time PCR experiments on the validation set patients confirmed that higher expression of miR-574-3p was associated with non-tumor relapse (p = 0.029) and better overall survival (p = 0.004).ConclusionsOur results suggest that the aberrant expression of the miRNAs identified in this study plays key roles in the progression of ESCC. miR-574-3p was suggested to have a tumor suppressor effect, and thus, to be a predictor of postoperative outcome in patients with ESCC.

Multiple Synchronous Sporadic Gastrointestinal Stromal Tumors in the Stomach and Jejunum

A 77-year-old patient was admitted to our hospital for the further examination of melena. A computed tomography scan detected two submucosal tumors (SMTs) in the stomach and jejunum. Double-balloon endoscopy revealed the presence of a delle on the jejunal SMT, suggesting that the SMT was the origin of the gastrointestinal bleeding. Both tumors were surgically resected and subsequently diagnosed via histology as gastrointestinal stromal tumors (GISTs). Furthermore, the two GISTs had different mutations in the c-kit gene, suggesting that they were derived from different clonal origins. This report depicts an extremely rare case of multiple synchronous sporadic GISTs in the stomach and jejunum.

The efficacy of steroids for postoperative persistent inflammatory reaction in a patient with barium peritonitis: A case report

Highlights • Residual barium in intraperitoneal cavity causes persistent inflammatory reaction.• Steroids are effective for persistent inflammation caused by residual barium.• If infectious or other inflammation origins exist, steroids should be avoided.