Taishi Hata

Increased Th17-Inducing Activity of CD14+ CD163low Myeloid Cells in Intestinal Lamina Propria of Patients With Crohn’s Disease

BACKGROUND & AIMS Abnormal activity of innate immune cells and T-helper (Th) 17 cells has been implicated in the pathogenesis of autoimmune and inflammatory diseases, including Crohns disease (CD). Intestinal innate immune (myeloid) cells have been found to induce development of Th17 cells in mice, but it is not clear if this occurs in humans or in patients with CD. We investigated whether human intestinal lamina propria cells (LPCs) induce development of Th17 cells and whether these have a role in the pathogenesis of CD. METHODS Normal intestinal mucosa samples were collected from patients with colorectal cancer and noninflamed and inflamed regions of mucosa were collected from patients with CD. LPCs were isolated by enzymatic digestion and analyzed for expression of HLA-DR, lineage markers CD14 and CD163 using flow cytometry. RESULTS Among HLA-DR(high) Lin(-) cells, we identified a subset of CD14(+) CD163(low) cells in intestinal LPCs; this subset expressed Toll-like receptor (TLR) 2, TLR4, and TLR5 mRNAs and produced interleukin (IL)-6, IL-1β, and tumor necrosis factor in response to lipopolysaccharide. In vitro co-culture with naïve T cells revealed that CD14(+) CD163(low) cells induced development of Th17 cells. CD14(+) CD163(low) cells from inflamed regions of mucosa of patients with CD expressed high levels of IL-6, IL-23p19, and tumor necrosis factor mRNAs, and strongly induced Th17 cells. CD14(+) CD163(low) cells from the noninflamed mucosa of patients with CD also had increased abilities to induce Th17 cells compared with those from normal intestinal mucosa. CONCLUSIONS CD14(+) CD163(low) cells in intestinal LPCs from normal intestinal mucosa induce differentiation of naive T cells into Th17 cells; this activity is increased in mucosal samples from patients with CD. These findings show how intestinal myeloid cell types could contribute to pathogenesis of CD and possibly other Th17-associated diseases.

Hepatic expression of ANG2 RNA in metastatic colorectal cancer.

We examined the RNA content of the gene encoding angiopoietin (Ang)‐2, a modifier of angiogenesis, in hepatic metastases of colorectal cancer (CRC) to explore the role of this protein in neovascularization of metastatic foci. Metastatic CRC exhibited notable blood flow and tumor vessel formation at tumor frontiers. Reverse‐transcription polymerase chain reaction assays indicated that the ANG2 RNA content was greater in metastatic CRC than in primary CRC. Investigation of metastatic foci using laser capture microdissection revealed that the RNA content of ANG2, but not ANG1, increased from the bordering liver region to the periphery of the metastatic disease, and also from the periphery to the intermediate portion of the metastatic lesion; immunohistochemical analysis confirmed that there was a corresponding gradual increase in Ang‐2 protein expression. Tie‐2, a receptor for angiopoietins, was preferentially expressed in the bordering liver region rather than in metastatic CRC. Vascular endothelial growth factor (VEGF) also exhibited an expression pattern similar to that of Ang‐2, and there was a significant correlation between the RNA content of ANG2 and that of VEGF in dissected samples (P = .002). Western blot analysis suggested that expression of Ang‐1, Ang‐2, Tie‐2, and VEGF may be regulated at a transcriptional level. The increase in ANG2 RNA content from the peripheral portion of the tumor to the intermediate portion, coinciding with the decrease in recruitment of periendothelial supporting cells around the vascular endothelial cells, suggests that Ang‐2 may play a role in the immaturity of tumor vessels. In conclusion, the current study suggests that Ang‐2 and VEGF may cooperate to enhance the formation of new blood vessels in metastases of CRC to the liver. (HEPATOLOGY 2004;39:528–539.)

The usefulness, indications, and complications of laparoscopy-assisted colectomy in comparison with those of open colectomy for colorectal carcinoma

The technique of laparoscopy-assisted colectomy (LAC) was developed for benign and malignant diseases of the colon and rectum; however, its feasibility and the associated clinical outcome remain unclear. We reviewed 45 patients who underwent LAC (LAC group) and 62 patients who underwent traditional open surgery (Open group) for colorectal carcinoma in our hospital, and compared the clinical data between the two groups in an effort to determine whether LAC is really minimally invasive and if it enhances the quality of life. So that the backgrounds of the patients in both groups were almost the same, we only compared data of patients with colorectal carcinoma of stages 0, I, and II. The duration of surgery in the Open group was significantly shorter for all procedures except sigmoid resection, but the blood loss was not significantly different between any of the procedures except for right colectomy. The time to the first passing of flatus and restarting oral intake, length of hospital stay, and duration of epidural analgesia were significantly shorter in the LAC group. The morbidity and mortality rates in the LAC group were almost the same as those in the Open group at 29.5% and 3.3% versus 22.6% and 1.6%, respectively. However, five major complications of LAC for advanced colorectal carcinomas might be prevented by performing an open procedure. In conclusion, LAC is a safe and minimally invasive surgical technique following which we can expect a faster recovery; however, patients with advanced colorectal carcinomas must be carefully selected for this operation.

Role of p21waf1/cip1 in effects of oxaliplatin in colorectal cancer cells

Clinical studies have shown that oxaliplatin, a novel platinum derivative, is a potent chemotherapeutic agent for colorectal cancer when combined with 5-fluorouracil and leucovorin. Although the toxic activity is based on covalent adducts between platinum and DNA, its actual biological behavior is mostly unknown. In an effort to explore the mechanism of tumor susceptibility to oxaliplatin, we examined the cytotoxic effects of oxaliplatin in colorectal cancer cell lines in reference to p53 gene status. Although p53 gene status did not clearly predict sensitivity to oxaliplatin, p53 wild-type cells including HCT116 were sensitive but HCT116 p53−/− were found to be resistant to oxaliplatin. Oxaliplatin caused strong p21waf1/cip1 induction and G0-G1 arrest in p53 wild-type cells, whereas cisplatin did not induce G0-G1 arrest. Assays using p53 wild but p21waf1/cip1 null HCT116 cells revealed that oxaliplatin did not show G0-G1 arrest and reduced growth-inhibitory effects, suggesting that p21waf1/cip1 may be a key element in oxaliplatin-treated p53 wild-type cells. Although HCT116 is DNA mismatch repair–deficient, a mismatch repair–proficient HCT116+ch3 cell line displayed similar responses with regard to p21waf1/cip1-mediated growth inhibition and G0-G1 arrest. In p53 mutant cells, on the other hand, oxaliplatin caused an abrupt transition from G1 to S phase and eventually resulted in G2-M arrest. This abrupt entry into S phase was associated with loss of the p21waf1/cip1 protein via proteasome-mediated degradation. These findings suggest that p21waf1/cip1 plays a role in oxaliplatin-mediated cell cycle and growth control in p53-dependent and -independent pathways.

Concurrent Targeting of KRAS and AKT by MiR-4689 Is a Novel Treatment Against Mutant KRAS Colorectal Cancer.

KRAS mutations are a major cause of drug resistance to molecular-targeted therapies. Aberrant epidermal growth factor receptor (EGFR) signaling may cause dysregulation of microRNA (miRNA) and gene regulatory networks, which leads to cancer initiation and progression. To address the functional relevance of miRNAs in mutant KRAS cancers, we transfected exogenous KRASG12V into human embryonic kidney 293 and MRC5 cells with wild-type KRAS and BRAF genes, and we comprehensively profiled the dysregulated miRNAs. The result showed that mature miRNA oligonucleotide (miR)-4689, one of the significantly down-regulated miRNAs in KRASG12V overexpressed cells, was found to exhibit a potent growth-inhibitory and proapoptotic effect both in vitro and in vivo. miR-4689 expression was significantly down-regulated in cancer tissues compared to normal mucosa, and it was particularly decreased in mutant KRAS CRC tissues. miR-4689 directly targets v-ki-ras2 kirsten rat sarcoma viral oncogene homolog (KRAS) and v-akt murine thymoma viral oncogene homolog 1(AKT1), key components of two major branches in EGFR pathway, suggesting KRAS overdrives this signaling pathway through inhibition of miR-4689. Overall, this study provided additional evidence that mutant KRAS functions as a broad regulator of the EGFR signaling cascade by inhibiting miR-4689, which negatively regulates both RAS/mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/AKT pathways. These activities indicated that miR-4689 may be a promising therapeutic agent in mutant KRAS CRC.

Depletion of JARID1B induces cellular senescence in human colorectal cancer

The global incidence of colorectal cancer (CRC) is increasing. Although there are emerging epigenetic factors that contribute to the occurrence, development and metastasis of CRC, the biological significance of epigenetic molecular regulation in different subpopulations such as cancer stem cells remains to be elucidated. In this study, we investigated the functional roles of the H3K4 demethylase, jumonji, AT rich interactive domain 1B (JARID1B), an epigenetic factor required for the continuous cell growth of melanomas, in CRC. We found that CD44(+)/aldehyde dehydrogenase (ALDH)(+) slowly proliferating immature CRC stem cell populations expressed relatively low levels of JARID1B and the differentiation marker, CD20, as well as relatively high levels of the tumor suppressor, p16/INK4A. Of note, lentiviral‑mediated continuous JARID1B depletion resulted in the loss of epithelial differentiation and suppressed CRC cell growth, which was associated with the induction of phosphorylation by the c‑Jun N‑terminal kinase (Jnk/Sapk) and senescence‑associated β‑galactosidase activity. Moreover, green fluorescent‑labeled cell tracking indicated that JARID1B‑positive CRC cells had greater tumorigenicity than JARID1B‑negative CRC cells after their subcutaneous inoculation into immunodeficient mice, although JARID1B‑negative CRC cells resumed normal growth after a month, suggesting that continuous JARID1B inhibition is necessary for tumor eradication. Thus, JARID1B plays a role in CRC maintenance. JARID1B may be a novel molecular target for therapy‑resistant cancer cells by the induction of cellular senescence.

CD49f-positive cell population efficiently enriches colon cancer-initiating cells

Cancer stem cells (CSCs) also known as cancer-initiating cells (CICs) show high tumorigenic activity and high chemo- and radiation resistance. It is, therefore, important to identify CSCs reliably to develop novel curative cancer treatments. In this study, we re-evaluated CSC markers of colorectal cancer for their cellular differentiation and tumorigenic activity, with the aim to identify reliable CSC markers. The rates of change in CD44, CD133, CD166, CD24, CD49f and CXCR4 expression during sodium butyrate (NaBT)-induced cell differentiation were assessed in HT29 and Caco2 colon cancer cell lines. Expression levels of target markers were assessed in clinical CRC samples. Tumorigenic activity was assessed on isolated cell fractions identified by multicolor flow cytometric analysis. In the cell differentiation assay, the average percent change was higher in CD44 (-98.2%) and CD49f (-74.4%) compared to CD133 (-17.9%) and CD166 (-49.4%). Expression of CD24 and CXCR4 appeared random in HT29 and Caco2. Expression of CD44, CD49f, CD133 and CD166 was confirmed in all four clinical CRC samples. Limiting dilution assay of CD44- and CD133-expressing cells revealed that only the CD133⁺CD44⁺ population possessed tumorigenic activity. Tumorigenesis was not affected by CD166 expression. Highly tumorigenic cells could be enriched in samples with higher CD49f expression; CD49f⁺ cells showed high tumorigenesis, whereas CD133⁺ and CD44⁺ cells that were negative for CD49f exhibited no tumorigenic activity. Multicolor analysis revealed that CD49f⁺ cells localized in CD44⁺ and CD133⁺ cell fractions. These findings demonstrated that CD49f is an important marker for identifying colorectal CSCs and suggest that the CD49f⁺ cell fraction may be the best candidate for colorectal CSCs.

Combination antiemetic therapy with aprepitant/fosaprepitant in patients with colorectal cancer receiving oxaliplatin-based chemotherapy (SENRI trial): a multicentre, randomised, controlled phase 3 trial.

INTRODUCTION The oral neurokinin-1 antagonist aprepitant is recommended in several guidelines for preventing chemotherapy-induced nausea & vomiting (CINV) due to highly emetogenic cancer chemotherapy. Little is known about the feasibility and safety of aprepitant in patients treated with oxaliplatin. METHODS In this multicentre, open label, randomised, phase 3 trial, we recruited patients with colorectal cancer who underwent an oxaliplatin-based chemotherapy. Patients were centrally randomised in a 1:1 ratio to the control group (5-HT3-receptor antagonist+dexamethasone) or aprepitant group (5-HT3-receptor antagonist+dexamethasone+aprepitant or fosaprepitant) in the first course. All patients were treated with aprepitant/fosaprepitant therapy in the second course. The primary end-point was the proportion of patients with no emesis. RESULTS A total of 413 patients entered this clinical trial from 25 centres in Japan. Significantly more patients in the aprepitant group achieved no vomiting overall and delayed phase than those in the control group (95.7% versus 83.6%, and 95.7% versus 84.7%, respectively). The aprepitant group also had statistically significantly higher percentages of no significant nausea, complete response and complete protection than the control group overall. In the control group, the percentages of no vomiting were higher in the second cycle than in the first cycle. The incidence of vomiting occurred day 7 or later was significantly higher in the control group compared with the aprepitant group. Other adverse events were not significant between the groups. CONCLUSION The aprepitant therapy was more effective than the control therapy for prevention of CINV in colorectal cancer patients receiving an oxaliplatin-based regimen.

Circulating miR-199a-3p as a novel serum biomarker for colorectal cancer

Serum microRNAs (miRNAs) have been shown to have potential for cancer diagnosis. The main objective of the present study was to identify a novel serum miRNA biomarker from patients with colorectal cancer (CRC). Microarray analysis of miRNA expression was performed using paired pre-operative and post-operative serum from 10 CRC patients. Expression of two miRNAs (let-7a and miR-199a-3p) was significantly decreased in the post-operative serum when compared to levels in the pre-operative serum (P=0.015 and 0.029, respectively). Quantitative real-time polymerase chain reaction (qRT-PCR) confirmed the decrease in the miRNAs in an extended number (n=30) of paired serum samples. Next, we examined the serum let-7a level in 32 non-cancer patients and 84 CRC patients but we found no significant difference (P=0.120). In contrast, miR199a-3p expression was significantly higher in the CRC patients than that in the non-cancer patients (P=0.016). Furthermore, clinical and pathological survey indicated that high expression of miR-199a-3p was significantly associated with deep wall invasion. Our data suggest that circulating miR-199a-3p could be a novel serum biomarker for CRC.

Oncometabolite D-2-Hydroxyglurate Directly Induces Epithelial-Mesenchymal Transition and is Associated with Distant Metastasis in Colorectal Cancer

Deranged metabolism is a hallmark of cancer, playing a significant role in driving the disease process. One such example is the induction of carcinogenesis by the oncometabolite D-2 hydroxyglutarate (D-2HG), which is produced by the mutated enzyme isocitrate dehydrogenase (IDH) occurring in subsets of leukaemias and brain tumours. The oncogenic property of D-2HG appears to stem from its ability to interfere with the activities of α-ketoglutarate-dependent dioxygenases, including the Jumonji family histone demethylases. Here, we find in colorectal cancer cells that even in the absence of IDH mutation, the levels of D-2HG and its enantiomer L-2HG were elevated through glutamine anaplerosis. D-2HG, but not L-2HG, increased the trimethylation of histone H3 lysine 4 of the promoter region of ZEB1, a master regulator of epithelial-mesenchymal transition (EMT), and increased the expression of the ZEB1 gene to directly induce EMT in colorectal cancer cells. EMT promotes the ability of cancer cells to invade the local tissue and enter into the bloodstream, leading to distant organ metastasis. D-2HG levels were elevated in colorectal cancer specimens, particularly in those associated with distant metastasis, supporting the observations in vitro and implicating the contribution of D-2HG in metastasis, the major cause of death in this disease.