Eiichi Morii

Critical role of Trib1 in differentiation of tissue-resident M2-like macrophages

Macrophages consist of at least two subgroups, M1 and M2 (refs 1, 2, 3). Whereas M1 macrophages are proinflammatory and have a central role in host defence against bacterial and viral infections, M2 macrophages are associated with responses to anti-inflammatory reactions, helminth infection, tissue remodelling, fibrosis and tumour progression. Trib1 is an adaptor protein involved in protein degradation by interacting with COP1 ubiquitin ligase. Genome-wide association studies in humans have implicated TRIB1 in lipid metabolism. Here we show that Trib1 is critical for the differentiation of F4/80+MR+ tissue-resident macrophages—that share characteristics with M2 macrophages (which we term M2-like macrophages)—and eosinophils but not for the differentiation of M1 myeloid cells. Trib1 deficiency results in a severe reduction of M2-like macrophages in various organs, including bone marrow, spleen, lung and adipose tissues. Aberrant expression of C/EBPα in Trib1-deficient bone marrow cells is responsible for the defects in macrophage differentiation. Unexpectedly, mice lacking Trib1 in haematopoietic cells show diminished adipose tissue mass accompanied by evidence of increased lipolysis, even when fed a normal diet. Supplementation of M2-like macrophages rescues the pathophysiology, indicating that a lack of these macrophages is the cause of lipolysis. In response to a high-fat diet, mice lacking Trib1 in haematopoietic cells develop hypertriglyceridaemia and insulin resistance, together with increased proinflammatory cytokine gene induction. Collectively, these results demonstrate that Trib1 is critical for adipose tissue maintenance and suppression of metabolic disorders by controlling the differentiation of tissue-resident M2-like macrophages.

MicroRNA-mediated downregulation of mTOR/FGFR3 controls tumor growth induced by Src-related oncogenic pathways.

The tyrosine kinase c-Src is upregulated in various human cancers, but the molecular mechanisms underlying c-Src-mediated tumor growth remain unclear. Here we examined the involvement of microRNAs in the c-Src-mediated tumor growth. Microarray profiling revealed that c-Src activation downregulates a limited set of microRNAs, including miR-99a, which targets oncogenic mammalian target of rapamycin (mTOR) and fibroblast growth factor receptor 3 (FGFR3). Re-expression of miR-99a suppressed tumor growth of c-Src-transformed cells, and this effect was restored by the overexpression of mTOR. The downregulation of miR-99a was also observed in epidermal growth factor- and Ras-transformed cells, and it was suppressed by inhibiting the mitogen-activated protein kinase (MAPK) pathway. Furthermore, miR-99a downregulation is associated with mTOR/FGFR3 upregulation in various human lung cancer cells/tissues. The tumorigenicity of these cells was suppressed by the introduction of miR-99a. These findings suggest that the miR-99a-mTOR/FGFR3 pathway is crucial for controlling tumor growth in a wide range of human cancers that harbor upregulation of the Src-related oncogenic pathways.

Expression of CUB domain containing protein (CDCP1) is correlated with prognosis and survival of patients with adenocarcinoma of lung.

CUB domain containing protein (CDCP1), a transmembrane protein with intracellular tyrosine residues which are phosphorylated upon activation, is supposed to be engaged in proliferative activities and resistance to apoptosis of cancer cells. Expression level of CDCP1 was examined in lung adenocarcinoma, and its clinical implications were evaluated. CDCP1 expression was immunohistochemically examined in lung adenocarcinoma from 200 patients. Staining intensity of cancer cells was categorized as low and high in cases with tumor cells showing no or weak and strong membrane staining, respectively. MIB‐1 labeling index was also examined. There were 113 males and 87 females with median age of 63 years. Stage of disease was stage I in 144 cases (72.0%), II in 19 (9.5%), and III in 37 (18.5%). Sixty of 200 cases (30.0%) were categorized as CDCP1‐high, and the remaining as CDCP1‐low. Significant positive correlation was observed between CDCP1‐high expression and relapse rate (P < 0.0001), poor prognosis (P < 0.0001), MIB‐1 labeling index (P < 0.0001), and occurrence of lymph node metastasis (P = 0.0086). There was a statistically significant difference in disease‐free survival (DFS) (P < 0.0001) and overall survival (OS) rates (P < 0.0001) between patients with CDCP1‐high and CDCP1‐low tumors. Univariate analysis showed that lymph node status, tumor stage, and CDCP1 expression were significant factors for both OS and DFS. Multivariate analysis revealed that only CDCP1 expression was an independent prognostic factor for both OS and DFS. CDCP1 expression level is a useful marker for prediction of patients with lung adenocarcinoma (Cancer Sci 2009; 100: 429–433).

Prognostic implication of types of tumor-associated macrophages in Hodgkin lymphoma

To evaluate roles of tumor-associated macrophages (TAMs) for prognosis of classical Hodgkin lymphoma (CHL). Expression of markers for TAMs, CD68, HLA-DR, CD163, HLA-DR/CD68 (M1), and CD163/CD68 (M2) was immunohistochemically examined in 82 cases with CHL. Positively stained cells were counted and correlation of number of TAMs and patients’ survival time was analyzed. Number of CD163+ cells and M2 cells was significantly correlated with shorter overall survival (Pu2009<u20090.05), while it was marginally significant for CD68+ cells (Pu2009=u20090.0827). HLA-DRu2009+u2009cells and M1 cells showed no significant correlation with overall survival. When confined to mixed cellularity subtype, number of M1 cells was correlated with favorable prognosis (Pu2009<u20090.05), while M2 did not (Pu2009=u20090.7). Older age and male sex were unfavorable factors for prognosis. At multivariate analysis, number of CD163+ cells, M2+ cells, and age were independent factors for poor overall survival (Pu2009=u20090.03, 0.02, and 0.01, respectively). CD163+ cells and M2 cells might work to be tumor promotive in CHL. M1 cells might be tumor suppressive in mixed cellularity type.

Tumour-associated macrophages in diffuse large B-cell lymphoma: a study of the Osaka Lymphoma Study Group.

Wada N, Zaki M A A, Hori Y, Hashimoto K, Tsukaguchi M, Tatsumi Y, Ishikawa J, Tominaga N, Sakoda H, Take H, Tsudo M, Kuwayama M, Morii E & Aozasa K u2028(2012) Histopathology 60, 313–319 u2028Tumour‐associated macrophages in diffuse large B‐cell lymphoma: a study of the Osaka Lymphoma Study Group

Pretreatment leukocytosis is an indicator of poor prognosis in patients with cervical cancer

OBJECTIVESnThe aim of this study was to investigate the prognostic value of pretreatment leukocytosis in patients with cervical cancer in relation to well-established conventional risk factors.nnnMETHODSnThe baseline characteristics and outcome data from 536 patients treated for cervical cancer between 1996 April to 2007 March were collected and reviewed. Cox proportional hazards regression model was used to identify independent prognostic factors for overall survival. Subsequently, the prognostic significance of pretreatment WBC count was prospectively investigated in 156 patients newly diagnosed cervical cancer from 2007 April to 2010 March.nnnRESULTSnIn a retrospective analysis, patients with leukocytosis (WBC ≥ 10,000/μl) showed significantly higher treatment failure rate (P < 0.0001) and shorter OS (P < 0.0001) than the patients without leukocytosis. Tumors from patients with leukocytosis showed significantly stronger immunoreactivity for G-CSF than those obtained from patients without leukocytosis. Multivariate analyses revealed that clinical stage, tumor diameter, histology, and elevated WBC count (≥ 10,000/μl) were significant prognostic factors in terms of overall survival. In a prospective investigation, patients with leukocytosis showed significantly higher treatment failure rate (P < 0.0001), shorter PFS (P < 0.0001), and higher serum G-CSF concentrations (p = 0.001) than the patients without leukocytosis. Multivariate analyses revealed that clinical stage, tumor diameter, and elevated WBC count were significant prognostic factors in terms of PFS.nnnCONCLUSIONnPretreatment leukocytosis is an independent prognostic factor in patients with cervical cancer. Our finding can be used to identify patients with poor prognosis and to design future tailored clinical trials.

MicroRNA-mediated upregulation of integrin-linked kinase promotes Src-induced tumor progression

The tyrosine kinase c-Src is upregulated in various human cancers; however, the molecular mechanisms underlying c-Src-mediated tumor progression remain unclear. Here we show that downregulation of microRNA (miR)-542-3p is tightly associated with tumor progression via c-Src-related oncogenic pathways. In c-Src-transformed fibroblasts and human cancer cells that overexpress c-Src, miR-542-3p is substantially downregulated, and the ectopic expression of miR-542-3p suppresses tumor growth. We identified the integrin-linked kinase (ILK) as a conserved target of miR-542-3p. ILK upregulation promotes cell adhesion and invasion by activating the integrin–focal adhesion kinase (FAK)/c-Src pathway, and can also contribute to tumor growth via the AKT and glycogen synthase kinase 3β pathways. MiR-542-3p expression is downregulated by the activation of c-Src-related signaling molecules, including epidermal growth factor receptor, K-Ras and Ras/Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase. In human colon cancer tissues, downregulation of miR-542-3p is significantly correlated with the upregulation of c-Src and ILK. Our results suggest that the novel c-Src–miR-542-3p–ILK–FAK circuit plays a crucial role in controlling tumor progression.

Expression Level of Hepatoma-Derived Growth Factor Correlates with Tumor Recurrence of Esophageal Carcinoma

Hepatoma-derived growth factor (HDGF) is thought to play an important role in the development and progression of carcinomas. In the present study, association of HDGF expression with recurrence and prognosis of esophageal carcinoma (EC) was examined. HDGF expression in 111 patients with EC (101 men and 10 women) with ages ranging from 38 to 82 (median, 61) years was analyzed by immunohistochemistry. Samples in which >90% of tumor cells exhibited nuclear and cytoplasmic HDGF immunoreactivity at levels greater than or equal to what is observed in the endothelial cells were regarded as HDGF expression level 1, and others as HDGF expression level 0. Thirty-seven of 111 patients showed level 1 HDGF expression. There was no correlation between HDGF expression and other clinicopathologic factors. Patients with level 1 expression showed poorer disease-free and overall survival (P < .05 for both) compared with those with level 0 expression. HDGF expression was an independent prognostic factor for patients with early (pT1–2) stage of the disease, but not for those with advanced (pT3–4) stage. HDGF expression level was shown to be a prognostic factor for EC.

A Case of Disseminated Peritoneal Leiomyomatosis Developing after Laparoscope-Assisted Myomectomy

A 36-year-old nulliparous woman developed multiple extra-uterine fibroids in the pelvic cavity years after laparoscopic myomectomy. Molecular genetic analysis by methylation-specific polymerase chain reaction (MSPCR) of the human X-linked androgen receptor gene and loss of heterozygosity (LOH) analysis at 5 microsatellite loci was performed on the tumors. All tumors showed an identical non-random X-chromosome inactivation pattern by MSPCR and an identical pattern of LOH was found in all the tumors by LOH analysis. This demonstrated that 3 fibroids resected 2 years later and 14 fibroids resected 6 years later were all metastatic tumors originating from the uterine leiomyoma found during the initial surgery, suggesting that morcellation before removal of the leiomyoma nodule during laparoscopic myomectomy may have been associated with the pathogenesis of this case.

Cancer stem-like cells of ovarian clear cell carcinoma are enriched in the ALDH-high population associated with an accelerated scavenging system in reactive oxygen species

OBJECTIVEnIn ovarian cancer cases, recurrence after chemotherapy is frequently observed, suggesting the involvement of ovarian cancer stem-like cells (CSCs). The chemoresistance of ovarian clear cell carcinomas is particularly strong in comparison to other epithelial ovarian cancer subtypes. We investigated the relationship between a CSC marker, aldehyde dehydrogenase 1 (ALDH1), and clinical prognosis using ovarian clear cell carcinoma tissue samples. Furthermore, we investigated the antioxidant mechanism by which CSCs maintain a lower reactive oxygen species (ROS) level, which provides protection from chemotherapeutic agents.nnnMETHODSnImmunohistochemical staining was performed to examine the CSC markers (CD133, CD44, ALDH1) using ovarian clear cell carcinoma tissue samples (n=81). Clear cell carcinoma cell lines (KOC-7C, OVTOKO) are separated into the ALDH-high and ALDH-low populations by ALDEFLUOR assay and fluorescence-activated cell sorting (FACS). We compared the intracellular ROS level, mRNA level of the antioxidant enzymes and Nrf2 expression of the two populations.nnnRESULTSnHigh ALDH1 expression levels are related to advanced stage in clear cell carcinoma cases. ALDH1 expression significantly reduced progression free survival. Other markers are not related to clinical stage and prognosis. ALDH-high cells contained a lower ROS level than ALDH-low cells. Antioxidant enzymes were upregulated in ALDH-high cells. ALDH-high cells showed increased expression of Nrf2, a key transcriptional factor of the antioxidant system.nnnCONCLUSIONSnALDH-positive CSCs might have increased Nrf2-induced antioxidant scavengers, which lower ROS level relevant to chemoresistance in ovarian clear cell carcinoma.