Sho Haneda

Inhibitor of apoptosis protein family as diagnostic markers and therapeutic targets of colorectal cancer

The apoptosis and antiapoptotic signaling pathways are important for regulating carcinogenesis and cancer progression, and for determining prognosis. Molecules involved in apoptosis represent potential cancer diagnostic markers and therapeutic targets. The inhibitor of apoptosis protein (IAP) family includes several important molecules involved in apoptosis that might represent such targets. Increasing evidence has demonstrated that the IAP family of proteins is integral for antiapoptotic and nuclear factor-κB signal transduction, and enhanced expression of IAPs contributes to colon carcinogenesis and its poor prognosis, as well as to drug resistance of tumors. X-linked IAP, cIAP1, cIAP2, and survivin are prognostic markers of colorectal cancer, and survivin and cIAP2 are also utilized to predict the effect of anticancer treatment in colorectal cancer patients. Novel therapies such as YM155 and LY2181308 targeting survivin, AEG35156 and phenoxodiol targeting X-linked IAP, AT-406 as a Smac mimetic, and survivin peptides are currently being evaluated in clinical trials. This report reviews the involvement of the IAP family in colorectal adenocarcinoma in order to summarize the role of the IAP family members as diagnostic and therapeutic targets, and to provide an overview of the future course of research in this area.

5-FU Metabolism in Cancer and Orally-Administrable 5-FU Drugs

5-Fluorouracil (5-FU) is a key anticancer drug that for its broad antitumor activity, as well as for its synergism with other anticancer drugs, has been used to treat various types of malignancies. In chemotherapeutic regimens, 5-FU has been combined with oxaliplatin, irinotecan and other drugs as a continuous intravenous infusion. Recent clinical chemotherapy studies have shown that several of the regimens with oral 5-FU drugs are not inferior compared to those involving continuous 5-FU infusion chemotherapy, and it is probable that in some regimens continuous 5-FU infusion can be replaced by oral 5-FU drugs. Historically, both the pharmaceutical industry and academia in Japan have been involved in the development of oral 5-FU drugs, and this review will focus on the current knowledge of 5-FU anabolism and catabolism, and the available information about the various orally-administrable 5-FU drugs, including UFT, S-1 and capecitabine. Clinical studies comparing the efficacy and adverse events of S-1 and capecitabine have been reported, and the accumulated results should be utilized to optimize the treatment of cancer patients. On the other hand, it is essential to elucidate the pharmacokinetic mechanism of each of the newly-developed drugs, to correctly select the drugs for each patient in the clinical setting, and to further develop optimized drug derivatives.

The long-term clinical course of pouchitis after total proctocolectomy and IPAA for ulcerative colitis.

BACKGROUND: Pouchitis is the most common long-term complication after restorative total proctocolectomy and IPAA for ulcerative colitis. OBJECTIVE: We examined the incidence, clinical aspects, and long-term outcome of patients with idiopathic pouchitis. DESIGN: This study was a retrospective review of medical records. PATIENTS: Included in the study were 284 patients with ulcerative colitis who underwent a total proctocolectomy and IPAA. MAIN OUTCOME MEASURES: We evaluated the cumulative risk and long-term outcome of pouchitis including the duration of disease, pattern of relapse, and responsiveness to antibiotic therapy. RESULTS: Sixty-four patients developed idiopathic pouchitis. The cumulative risk was 10.7% at 1 year, 17.2% at 2 years, 24.0% at 5 years, and 38.2% at 10 years. At their first pouchitis episode, 45 patients had acute pouchitis, 19 patients had chronic pouchitis, and all patients received antibiotic therapy with oral ciprofloxacin and/or metronidazole. The efficacy of the therapy was 96.6% initially. Forty-five patients had antibiotic-responsive pouchitis, 17 patients had antibiotic-dependent pouchitis, and 2 patients had antibiotic-refractory pouchitis at their first episode. Whereas 20 of 45 patients (44.4%) with initially acute pouchitis experienced 2 or more relapses, 16 of 19 patients (84.2%) with initially chronic pouchitis had 2 or more relapses. After taking into account the relapses, the number of patients with antibiotic-responsive pouchitis decreased from 45 to 40, the number with antibiotic-dependent pouchitis increased from 17 to 20, and the number with antibiotic-refractory pouchitis increased from 2 to 4. Among the 4 patients with antibiotic-refractory pouchitis, 3 patients had Clostridium difficile-associated pouchitis. LIMITATIONS: This study was retrospective. CONCLUSION: The patients with chronic pouchitis at the first episode tend to have a higher incidence of relapse. In some patients, the responsiveness to antibiotic therapy changes during follow-up. When patients with pouchitis do not respond to standard antibiotic therapy, then the occurrence of C difficile infection should be considered.

Assessment of the Japanese Inflammatory Bowel Disease Questionnaire in patients after ileal pouch anal anastomosis for ulcerative colitis

BackgroundThe Inflammatory Bowel Disease Questionnaire (IBDQ) is the most widely used disease-specific health-related quality of life questionnaire for patients with inflammatory bowel disease. However, little has been reported about the validation of IBDQ for patients with ulcerative colitis after surgery. The aim of this study was to assess the validity and reliability of the Japanese version of IBDQ in patients with ulcerative colitis after total proctocolectomy and ileal pouch anal anastomosis (IPAA).MethodsThe validity and reliability of the Japanese IBDQ were assessed in patients with ulcerative colitis who had received IPAA in our hospital. We mailed them the Japanese IBDQ and a supplemental questionnaire on bowel function, which was developed at our institution. Internal consistency, discriminative validity, and factor validity were assessed.ResultsOf the 121 patients to whom we sent the questionnaires, 64 patients (53%) participated in this study. The Japanese IBDQ scores correlated well with Cronbach’s alpha value (0.800 to 0.923) and daily life satisfaction score (Pearson’s r, 0.492 to 0.700). The total IBDQ score and two subscale scores of the IBDQ, “bowel symptoms” and “systemic symptoms,” correlated well with daily bowel-movement frequency (Pearson’s r, −0.256 to −0.329). Factor analysis revealed a four-factor structure, and all correlations among factors were moderately positive (0.337 to 0.465). Although the factor distribution was not clearly divided into the four IBDQ subscales, these four factors showed a marked tendency to represent the IBDQ subscales independently.ConclusionsThe Japanese IBDQ is a valid and reliable instrument for the assessment of Japanese patients with ulcerative colitis after IPAA.

In vivo induction of prostasin mRNA in colonic epithelial cells by dietary sodium depletion and aldosterone infusion in rats.

BackgroundParallel induction of prostasin, a novel serine protease, together with epithelial sodium channel (ENaC) in the colon, may be essential for physiological response to increased circulating aldosterone. The aim of the present study was to investigate whether aldosterone induces prostasin mRNA in parallel with enhanced expression of ENaC in colonic epithelial cells.MethodsSprague-Dawley rats were maintained on a sodium-depleted diet or subjected to continuous aldosterone infusion up to 4 weeks. Rats were necropsied at 1, 2, or 4 weeks after the beginning of each treatment. Blood was immediately collected and the large intestine was removed. Plasma aldosterone and arginine-vasopressin (AVP) levels were measured by radio-immunoassay. Epithelial cells were isolated from the right and left colon and RNA was extracted. Expression of prostasin and the α-, β-, and γ-subunits of ENaC was evaluated by quantitative RT-PCR or Northern blot analysis. In another series of experiments, T84 cells were stimulated with aldosterone, dexamethasone, and AVP alone or in combination, and prostasin mRNA was measured by quantitative RT-CPR.ResultsTreatment with sodium-depleted diet and aldosterone infusion resulted in an increase of plasma aldosterone and induction of prostasin mRNA in the left colon. Expression of three subunits of ENaC also increased in the left colon. Induction of prostasin mRNA was observed when T84 cells were stimulated with corticosteroids plus AVP in vitro.ConclusionsAldosterone has a pivotal role for increasing expression of prostasin in epithelial cells of the left colon. AVP may have a synergistic effect on aldosterone-mediated prostasin induction.

A Shift from Colon- to Ileum-Predominant Bacteria in Ileal-Pouch Feces Following Total Proctocolectomy

BackgroundWe previously investigated fecal flora of the pouch after total proctocolectomy using terminal restriction fragment polymorphism analysis. Although the results of the cluster analysis demonstrated clearly that bacterial populations, including an unidentified bacteria generating a 213-bp PCR fragment, moved toward a colon-like community in the pouch, it did not track changes in the individual species of fecal bacteria.AimsThe aim of the present study was to estimate genome copy number of ten bacterial species, clusters, groups, or subgroups (including the bacteria generating 213-bp fragment in the previous study) in feces samples from pouches at various times following ileostomy closure.MethodsA total of 117 stool samples were collected from patients with ulcerative colitis after surgery as well as healthy volunteers. We used real-time polymerase chain reaction of the 16S rRNA gene to estimate genome copy numbers for the nine bacterial populations and the bacteria generating 213-bp fragment after identification by DNA sequencing.ResultsWe demonstrated a time-dependent increase in the number of anaerobic and colon-predominant bacteria (such as Clostridium coccoides, C. leptum, Bacteroides fragilis and Atopobium) present in proctocolectomy patients after stoma closure. In contrast, numbers of ileum-predominant bacterial species (such as Lactobacillus and Enterococcus faecalis) declined.ConclusionsOur data confirm previous findings that fecal flora in the pouch after total proctocolectomy changes significantly, and further demonstrate that the number and diversity of ileal bacteria decreases while a more colon-like community develops. The present data are essential for the future analysis of pathological conditions in the ileal pouch.

Aldosterone enhances 11β-hydroxysteroid dehydrogenase type 2 expression in colonic epithelial cells in vivo

Objective 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) metabolizes glucocorticoids, thus enabling aldosterone to bind to the mineralocorticoid receptor. However, little is known about the regulatory mechanism of epithelial 11β-HSD2 expression in the gut. Material and methods Sprague-Dawley rats were maintained on a sodium-depleted diet or subjected to continuous aldosterone infusion for 4 weeks. Plasma aldosterone and arginine-vasopressin (AVP) levels were measured by radioimmunoassay. Expression of 11β-HSD2 in colonic epithelia was evaluated by Northern blotting and immunohistochemistry. T84 and Caco2 cells were stimulated with aldosterone, dexamethasone and AVP alone or in combination, and 11β-HSD2 mRNA was measured by quantitative reverse transcription polymerase chain reaction (RT-PCR). Results Sodium-depleted and aldosterone-infused rats showed an increase of plasma aldosterone and AVP. Both treatments resulted in induction of 11β-HSD2 in the colonic epithelia at mRNA and protein levels. Positive immunoreactivity was detected in the cytoplasm of the surface epithelia in control rats. In contrast, epithelial cells in the crypt also showed immunoreactivity for 11β-HSD2 in the proximal colon of dietary sodium-depleted and aldosterone-infused rats. Induction of 11β-HSD2 mRNA was observed when T84 cells were stimulated with corticosteroids plus AVP. Conclusions Aldosterone has a pivotal role by increasing expression of 11β-HSD2 in epithelial cells of the colon. AVP may act as a synergistic hormone in aldosterone-mediated 11β-HSD2 induction.

Comparative study of epithelial gene expression in the small intestine among total proctocolectomized, dietary sodium-depleted, and aldosterone-infused rats

We previously demonstrated enhanced plasma aldosterone, ileal activation of epithelial sodium channel (ENaC), and induction of 11β-hydroxysteroid dehydrogenase type 2 after total proctocolectomies in rats. However, factors other than circulating aldosterone may cause molecular induction associated with sodium transport. Sprague-Dawley rats were treated with sodium-deficient diets or subcutaneous aldosterone infusion for 4 weeks. Rats also underwent total proctocolectomies as positive control. We extracted epithelial RNA from the distal small intestine and compared mRNA expression of the α, β, and γ subunits of ENaC, prostasin, sodium glucose transporter 1 (SGLT1), and the α1 and β1 subunits of Na_/K±ATPase among control, total proctocolectomized, dietary sodium-depleted, and aldosteroneinfused rats by quantitative reverse transcription-polymerase chain reaction or Northern blotting. A significant increase in aldosterone was noted in sodium-depleted and aldosterone-infused rats. The induction of three subunits of ENaC and prostasin mRNA was observed in proctocolectomized, aldosterone-infused rats but not in dietary sodium-depleted rats. The levels of the α1 and β1 subunits of Na_/K±ATPase were similar among the experimental groups. SGLT1 mRNA was induced only in proctocolectomized rats. The molecular induction of ENaC, prostasin, and SGLT1 is unique for total proctocolectomized rats. Aldosterone infusion can induce several essential molecules for sodium absorption, as seen in total proctocolectomy.

Factors Affecting the Bowel Function after Proctocolectomy and Ileal J Pouch–Anal Anastomosis for Ulcerative Colitis

The aim was to study determinants of postoperative bowel function after restorative proctocolectomy for ulcerative colitis. Medical records of patients who underwent proctocolectomy with ileal J pouch-anal anastomosis (IPAA) in two- or three-stage operations and whose status of defecation was known via a questionnaire were retrospectively reviewed. Bowel function, including stool frequency, stool consistency, and degree of nighttime soiling, was correlated with age at the time of surgery, time after ileostomy closure, mean resting anal pressure, longitudinal length of ileal J pouch, and duration of fecal diversion by using univariate and multivariate analyses. Stool frequency decreased significantly with time after ileostomy closure in both univariate and multivariate analyses. Stool frequency tended to be less in patients having a long J pouch, but the correlation was not significant (P=0.071) in univariate analysis. Nighttime soiling ameliorated with time after ileostomy closure in multivariate, but not univariate, analysis. Deterioration of nighttime soiling was seen in patients whose duration for fecal diversion was long, both in univariate (P=0.068) and multivariate (P=0.052) analyses. Stool consistency was related to none of the five factors investigated. These results indicate that as the time after surgery increases, stool frequency decreases and nighttime soiling ameliorates. Delaying ileostomy closure because of anticipated postoperative incontinence does not significantly alter postoperative continence.

A Unique Variant of Afferent Limb Syndrome After Ileal Pouch–Anal Anastomosis: A Case Series and Review of the Literature

BackgroundAfferent limb syndrome is a relatively rare cause of small bowel obstruction after restorative total proctocolectomy with ileal pouch–anal anastomosis for patients with ulcerative colitis or familial adenomatous polyposis.DiscussionThis report describes three patients who developed recurrent small bowel obstruction after ileal pouch–anal anastomosis. The bowel obstruction was caused by torsion of the ileum at the inlet of the ileal J-pouch, which was thought to be a variant of afferent limb syndrome. This variant of afferent limb syndrome is characterized by a flexible afferent limb of the pelvic pouch due to the lack adhesion of the ileum in the abdominal cavity. Preoperative diagnosis required multiple series of contrast small bowel enemas. Strictureplasty and ileopexy effectively resolved the recurrent bowel obstruction caused by this variant of afferent limb syndrome.