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β-TrCP is the substrate recognition subunit of an SCF-type ubiquitin ligase. We recently showed that deletion of the genes for both β-TrCP1 and β-TrCP2 paralogs in germ cells of male mice resulted in accumulation of the transcription factor DMRT1 and spermatogenic failure, whereas systemic β-TrCP1 knockout combined with β-TrCP2 knockdown had previously been shown to lead to disruption of testicular organization and accumulation of the transcription factor SNAIL. Here we investigated β-TrCP function in Sertoli cells by generating mice with targeted deletion of the β-TrCP2 gene in Sertoli cells on a background of whole-body β-TrCP1 knockout. Loss of β-TrCP in Sertoli cells caused infertility due to a reduction in the number of mature sperm. Whereas spermatogonia were not affected, male germ cells entered meiosis prematurely and the number of round spermatids was reduced in the mutant mice. Extracts of Sertoli cells and of the testis from the mutant mice manifested accumulation of SNAIL, and expression of the SNAIL target gene for E-cadherin was down-regulated in Sertoli cells from these animals. Our results indicate that β-TrCP in Sertoli cells regulates Sertoli cell-germ cell interaction through degradation of SNAIL, with such regulation being critical for sperm development., (Copyright © 2018 Elsevier Inc. All rights reserved.)

HIV-1 expresses several accessory proteins to counteract host anti-viral restriction factors to facilitate viral replication and disease progression. One such protein, Vpr, has been implicated in affecting multiple cellular processes, but its mechanism remains elusive. Here we report that Vpr targets TET2 for polyubiquitylation by the VprBP-DDB1-CUL4-ROC1 E3 ligase and subsequent degradation. Genetic inactivation or Vpr-mediated degradation of TET2 enhances HIV-1 replication and substantially sustains expression of the pro-inflammatory cytokine interleukin-6 (IL-6). This process correlates with reduced recruitment of histone deacetylase 1 and 2 to the IL-6 promoter, thus enhancing its histone H3 acetylation level during resolution phase. Blocking IL-6 signaling reduced the ability of Vpr to enhance HIV-1 replication. We conclude that HIV-1 Vpr degrades TET2 to sustain IL-6 expression to enhance viral replication and disease progression. These results suggest that disrupting the Vpr-TET2-IL6 axis may prove clinically beneficial to reduce both viral replication and inflammation during HIV-1 infection., (Copyright © 2018 Elsevier Inc. All rights reserved.)

PurposeNeonatal encephalopathy, which is characterized by a decreased level of consciousness, occurs in 1-7/1,000 live-term births. In more than half of term newborns, there is no identifiable etiological factor. To identify underlying genetic defects, we applied whole-exome sequencing (WES) in term newborns with neonatal encephalopathy as a prospective cohort study.MethodsTerm newborns with neonatal encephalopathy and no history of perinatal asphyxia were included. WES was performed using patient and both parents' DNA.ResultsNineteen patients fulfilling inclusion criteria were enrolled. Five patients were excluded owing to withdrawal of consent, no parental DNA samples, or a genetic diagnosis prior to WES. Fourteen patients underwent WES. We confirmed a genetic diagnosis in five patients (36%): epileptic encephalopathy associated with autosomal dominant de novo variants in SCN2A (p.Met1545Val), KCNQ2 (p.Asp212Tyr), and GNAO1 (p.Gly40Arg); lipoic acid synthetase deficiency due to compound heterozygous variants in LIAS (p.Ala253Pro and p.His236Gln); and encephalopathy associated with an X-linked variant in CUL4B (p.Asn211Ser).ConclusionWES is helpful at arriving genetic diagnoses in neonatal encephalopathy and/or seizures and brain damage. It will increase our understanding and probably enable us to develop targeted neuroprotective treatment strategies.

Recognition of gene promoters by RNA polymerase II is mediated by general transcription factor IID (TFIID), which has been thought to be a static complex and to play a passive role in the regulation of gene expression under the instruction of gene-specific transcription factors. Here we show that transforming growth factor β (TGF-β) induced degradation of the TFIID subunit TAF7 in cultured mouse mammary epithelial cells and that this effect was required for proliferative arrest in response to TGF-β stimulation. TGF-β stimulated transcription of the gene for the ubiquitin ligase TRIM26, which was shown to ubiquitylate TAF7 and thereby to target it for proteasomal degradation. Sustained exposure of cells to TGF-β resulted in recovery from proliferative arrest in association with amplification of the Myc proto-oncogene, with MYC inhibiting TRIM26 induction by TGF-β. Our data thus show that TFIID is not simply a general mediator of transcription but contributes to the regulation of transcription in response to cell stimulation, playing a key role in the cytostatic function of TGF-β., (Copyright © 2018 American Society for Microbiology.)

The mitosis-meiosis transition is essential for spermatogenesis. Specific and timely downregulation of the transcription factor DMRT1, and consequent induction of Stra8 expression, is required for this process in mammals, but the molecular mechanism has remained unclear. Here, we show that β-TrCP, the substrate recognition component of an E3 ubiquitin ligase complex, targets DMRT1 for degradation and thereby controls the mitosis-meiosis transition in mouse male germ cells. Conditional inactivation of β-TrCP2 in male germ cells of β-TrCP1 knockout mice resulted in sterility due to a lack of mature sperm. The β-TrCP-deficient male germ cells did not enter meiosis, but instead underwent apoptosis. The induction of Stra8 expression was also attenuated in association with the accumulation of DMRT1 at the Stra8 promoter in β-TrCP-deficient testes. DMRT1 contains a consensus β-TrCP degron sequence that was found to bind β-TrCP. Overexpression of β-TrCP induced the ubiquitylation and degradation of DMRT1. Heterozygous deletion of Dmrt1 in β-TrCP-deficient spermatogonia increased meiotic cells with a concomitant reduction of apoptosis. Collectively, our data indicate that β-TrCP regulates the transition from mitosis to meiosis in male germ cells by targeting DMRT1 for degradation., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2017. Published by The Company of Biologists Ltd.)

Repair of damaged DNA is critical for maintenance of genetic information. In eukaryotes, DNA double-strand breaks (DSBs) are recognized by the Ku70-Ku80 heterodimer, which then recruits proteins that mediate repair by nonhomologous end joining (NHEJ). Prolonged retention of Ku70/80 at DSBs prevents completion of repair, however, with ubiquitylation of Ku80 having been implicated in Ku70/80 dissociation from DNA. Here, we identify RNF126 as a ubiquitin ligase that is recruited to DSBs and ubiquitylates Ku80, with UBE2D3 serving as an E2 enzyme. Knockdown of RNF126 prevented Ku70/80 dissociation from DSBs and inhibited break repair. Attenuation of Ku80 ubiquitylation by replacement of ubiquitylation site lysines with arginine residues delayed Ku70/80 release from chromatin after DSB induction by genotoxic insults. Together, our data indicate that RNF126 is a novel regulator of NHEJ that promotes completion of DNA repair by ubiquitylating Ku80 and releasing Ku70/80 from damaged DNA., (Copyright © 2017 American Society for Microbiology.)

The SCF β-TRCP E3 ubiquitin ligase complex plays pivotal roles in normal cellular physiology and in pathophysiological conditions. Identification of β-transducin repeat-containing protein (β-TRCP) substrates is therefore critical to understand SCF β-TRCP biology and function. We used a β-TRCP-phosphodegron motif-specific antibody in a β-TRCP substrate screen coupled with tandem mass spectrometry and identified multiple β-TRCP substrates. One of these substrates was Lipin1, an enzyme and suppressor of the family of sterol regulatory element-binding protein (SREBP) transcription factors, which activate genes encoding lipogenic factors. We showed that SCF β-TRCP specifically interacted with and promoted the polyubiquitination of Lipin1 in a manner that required phosphorylation of Lipin1 by mechanistic target of rapamycin 1 (mTORC1) and casein kinase I (CKI). β-TRCP depletion in HepG2 hepatocellular carcinoma cells resulted in increased Lipin1 protein abundance, suppression of SREBP-dependent gene expression, and attenuation of triglyceride synthesis. Moreover, β-TRCP1 knockout mice showed increased Lipin1 protein abundance and were protected from hepatic steatosis induced by a high-fat diet. Together, these data reveal a critical physiological function of β-TRCP in regulating hepatic lipid metabolic homeostasis in part through modulating Lipin1 stability., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2017, American Association for the Advancement of Science.)

Purpose: In laparoscopic colorectal cancer (Lap-CRC) surgery, determination of a suitable mesentery division line and the appropriate degree of lymphadenectomy by tracing the blood supply is critical. We performed visualization of the lymph and blood flow by laparoscopic indocyanine green (ICG) fluorescence imaging (Lap-IGFI)., Methods: ICG is injected into the submucosa near the tumor via colonoscopy, and the lymph flow is observed. Intestinal blood flow is evaluated by administering ICG intravenously., Results: For lymph flow, visualization of the main lymph node basin helped to determine the surgical division line for cases in which the blood flow was not completely visualized. Lap-IGFI changed the surgical plan of the lymphadenectomy in 23.5 %. In our experience, the metastatic rate of ICG-positive nodes was 10.0 %, and the metastatic rate of ICG-negative nodes was 5.3 %. Furthermore, there were no metastatic nodes that were ICG negative more than 5 cm from the tumor. For blood flow, the blood flow distribution of the intestinal wall from the last branch of the vasa recta of the anastomotic site was clearly visualized and proved useful in choosing the extent of intestinal resection. Lap-IGFI changed the surgical plan of the extensive intestinal resection in 16.7 %., Conclusions: Lap-IGFI can noninvasively provide detailed lymph and blood flow information and is a useful device to aid in the accurate identification of individual patients' lymph drainage. This helps dictate adequate lymphadenectomy and the extent of intestinal resection in Lap-CRC surgery.

Ubiquitin is a 76-amino acid protein whose conjugation to protein targets is a form of post-translational modification. Protein ubiquitylation is characterized by the covalent attachment of the COOH-terminal carboxyl group of ubiquitin to an amino group of the substrate protein. Given that the NH2 -terminal amino group is usually masked, internal lysine residues are most often targeted for ubiquitylation. Polyubiquitylation refers to the formation of a polyubiquitin chain on the substrate as a result of the ubiquitylation of conjugated ubiquitin. The structures of such polyubiquitin chains depend on the specific lysine residues of ubiquitin targeted for ubiquitylation. Most of the polyubiquitin chains other than those linked via lysine-63 and methionine-1 of ubiquitin are recognized by the proteasome and serve as a trigger for substrate degradation. In contrast, polyubiquitin chains linked via lysine-63 and methionine-1 serve as a binding platform for proteins that function in immune signal transduction or DNA repair. With the exception of a few targets such as histones, the functions of protein monoubiquitylation have remained less clear. However, recent proteomics analysis has shown that monoubiquitylation occurs more frequently than polyubiquitylation, and studies are beginning to provide insight into its biologically important functions. Here, we summarize recent findings on protein monoubiquitylation to provide an overview of the targets and molecular functions of this modification., (© 2015 The Authors Genes to Cells published by Molecular Biology Society of Japan and Wiley Publishing Asia Pty Ltd.)

Background: Endoscopic resection (ER) of tumors causes inflammation, edema, fibrosis, and adhesions in the surrounding tissue. However, little is known about the effect of ER on subsequent laparoscopic surgery for rectal tumors. The objective of this retrospective study was to analyze the effect of ER on subsequent laparoscopic surgery for rectal tumors., Methods: Twenty-eight patients underwent laparoscopic surgery for rectal adenocarcinoma with submucosal invasion or a rectal neuroendocrine tumor at our hospital between January 2005 and December 2012. A group of 14 patients who underwent laparoscopic surgery with previous ER was compared to a group of 14 patients who underwent laparoscopic surgery without previous ER., Results: Though most fibrosis involved the submucosa after polypectomy and endoscopic mucosal resection, fibrosis after endoscopic submucosal dissection involved the muscularis propria in two patients, and the subserosa in one patient. There were no statistically significant differences in clinical outcomes between the groups., Conclusion: Laparoscopic surgery after ER for rectal tumors is safe and feasible. Laparoscopic surgery is the reasonable first-choice for radical treatment of rectal tumors after ER.

Variants in cullin 4B (CUL4B) are a known cause of syndromic X-linked intellectual disability. Here, we describe an additional 25 patients from 11 families with variants in CUL4B. We identified nine different novel variants in these families and confirmed the pathogenicity of all nontruncating variants. Neuroimaging data, available for 15 patients, showed the presence of cerebral malformations in ten patients. The cerebral anomalies comprised malformations of cortical development (MCD), ventriculomegaly, and diminished white matter volume. The phenotypic heterogeneity of the cerebral malformations might result from the involvement of CUL-4B in various cellular pathways essential for normal brain development. Accordingly, we show that CUL-4B interacts with WDR62, a protein in which variants were previously identified in patients with microcephaly and a wide range of MCD. This interaction might contribute to the development of cerebral malformations in patients with variants in CUL4B., (© 2014 WILEY PERIODICALS, INC.)

Objective: To introduce the prophylactic laparoscopic lateral pelvic lymph node dissection performing by remarking the vesicohypogastric fascia following total mesorectal excision for patients with advanced lower rectal cancer without radiological evidence of lymph node involvement., Surgical Method: We set 5 ports for conventional laparoscopic rectal surgery. During the prophylactic laparoscopic lateral pelvic lymph node dissection, we retrieved the lymph nodes from the internal iliac area and obturator area. We recognized the pelvic nerve plexus, vesicohypogastric fascia (including internal iliac vessels), and parietal fascia (psoas muscle fascia, pubic bone and internal obturator muscle fascia) as the dissection borders from internal to external. Of note, the vesicohypogastric fascia can be recognized under magnified clear vision, and can be preserved by precise dissection, resulting in reduced hemorrhage from the internal iliac vessels and complications such as urinary dysfunction., Conclusion: Prophylactic laparoscopic lateral pelvic lymph node dissection after remarking on the vesicohypogastric fascia may contribute to a less invasive surgery compared with conventional laparoscopic lateral pelvic lymph node dissection.

Purpose: The purpose of this study was to evaluate the clinicopathological features of mucinous adenocarcinoma associated with perianal fistulas (MAF), to assess the importance of preoperative MRI analysis, and to determine the optimal surgery., Methods: We performed a retrospective analysis of the data from seven patients with MAF treated at our hospital between 2000 and 2013, and herein discuss the importance of preoperative magnetic resonance imaging (MRI) and of radical surgery., Results: The male to female ratio was 5:2, and the mean age of the patients was 63 years old (28-70). The median duration of chronic fistulation was 16 years (5-40). The tumor extension was classified as II+III+IV in five patients and as II+III in 2 patients according to the Sumikoshi classification, as determned by pelvic MRI. The performed surgeries were 3 abdominoperineal resections with sacral resection and 4 pelvic exenterations with sacral resection. Two local recurrences developed in patients with R1 resection, and 1 distant metastasis occurred in 1 patient with R0 resection., Conclusion: For patients with MAF, a curative surgical resection is the only definitive treatment that can be expected to provide a good prognosis. The application of the Sumikoshi classification using MRI may provide a precise assessment of the extension of MAF, which can allow the appropriate surgery to be selected for the patients with MAF.

The authors present a case of rectal carcinoid tumor with lateral lymph node metastases and liver metastases that was successfully treated by 4 resections. A 70-year-old man was diagnosed with a rectal carcinoid tumor (20 mm in diameter) with submucosal (SM) invasion. Radical resection was performed at 25 months, 38 months, and 57 months, when abdominal computed tomography (CT) revealed metachronous liver metastases of the rectal carcinoid tumor. At 50 months, metachronous lateral lymph node metastases were also revealed. Three hepatectomies and a laparoscopic lateral lymph node dissection were performed. The patient is currently free of disease at 25 months after the last intervention.

Endoscopic submucosal dissection involves dissecting manipulation performed with tumors in an exposed condition for a long period of time. Thus, there is a risk for implantation of tumor cells. The objectives of this study were to examine exfoliated tumor cells after colorectal endoscopic submucosal dissection and to elucidate the effectiveness of intraluminal lavage to remove these cells. The subjects were 8 patients who had undergone colorectal endoscopic submucosal dissection at our hospital between September and December 2012. A retrospective study was conducted on the cytological findings of intraluminal lavage samples in these patients. Seven of the 8 patients (88%) had exfoliated tumor cells in the lavage samples at the beginning of lavage. Only 3 patients (3 8%) had exfoliated tumor cells after lavage with 300 ml of water. A large number of tumor cells were thought to have exfoliated into the intestinal lumen after endoscopic submucosal dissection. Sufficient intraluminal lavage after colorectal endoscopic submucosal dissection is necessary to remove exfoliated tumor cells.

We report a case of local recurrence of cancer after rectal endoscopic submucosal dissection (ESD). A 52-year-old male underwent a curative resection with ESD for rectal intramucosal cancer. Seventy-four months after ESD, surveillance colonoscopy showed an elevated lesion on the ESD scar, suspicious of a recurrence. The patient subsequently underwent a low anterior resection (intersphincteric) with lymph node dissection. Pathology revealed a well-differentiated adenocarcinoma, similar to the ESD specimen. We suspected that the local recurrence was caused by implantation of tumor cells during the ESD, due to surgical manipulation performed with the tumor in an exposed setting for a long period of time.

Objective: The aim of this study was to evaluate the outcomes of patients who underwent extensive pelvic surgery for locally advanced primary or recurrent non-colorectal pelvic malignancies., Patients and Methods: We performed a retrospective review of the medical records of 19 patients with non-colorectal pelvic malignancies who underwent extensive surgery at our institution between January 2005 and May 2013. Overall survival and progression-free survival were estimated using the Kaplan-Meier method and compared using the logrank test., Results: With regard to tumor histology, 6 patients (31.6%) had gynecological tumors, 8( 42.1%) had urological tumors, 2( 10.5%) had sarcomas, and 3( 15.8%) had other malignancies. Total pelvic exenteration was performed in 13 patients (68.4%), and other procedures were performed in 6 patients( 31.6%). For all patients, the median operation time and blood loss were 699 min and 2,930 mL, respectively. Complete tumor resection( R0) was achieved in 13 patients( 68.4%), and 16 patients had complications( 84.2%). The median overall survival was 18.5 months for patients who underwent R0 resection, compared with 7.3 months for those who underwent R1/R2 surgery (p=0.113), and the median progression-free survival was 7.3 months for cases of R0 resection, compared with 2.0 months for cases of R1/R2 surgery (p=0.035)., Conclusion: Our findings indicate that extensive pelvic surgery may be an optimal treatment for some patients with locally advanced primary or recurrent non-colorectal pelvic malignancies. Careful patient selection according to oncological, anatomical, and patient-related factors may improve the outcomes of patients undergoing this extensive, aggressive pelvic surgical procedure.

Radical surgery is often necessary in patients with local recurrence of rectal cancer or in those with carcinoma associated with an anal fistula. The surgery may include extended excision of the perineal area and can create a large dead space in the pelvis and a large skin defect, often necessitating reconstruction of the pelvic floor using rectus abdominis musculocutaneous (RAM) flap transposition. Wound dehiscence and incisional hernia are common complications of RAM flap transposition. We report herein our encounter with 3 patients in whom we used a "sliding door" technique for reconstruction of the abdominal wall after the creation of a RAM flap. One patient underwent abdominoperineal resection with sacrectomy and RAM flap transposition; he experienced a postoperative surgical site infection and wound dehiscence, which we urgently repaired by reconstructing the abdominal wall using the sliding door technique. Two other patients underwent posterior pelvic exenteration with sacrectomy and RAM flap transposition. These patients underwent simultaneous abdominal wall reconstruction using the sliding door technique. No patient experienced postoperative pelvic sepsis, wound dehiscence, or incisional hernia. The sliding door technique might be useful for preventing wound dehiscence and incisional hernia in patients undergoing RAM flap transposition.

The terminal step in the ubiquitin modification system relies on an E3 ubiquitin ligase to facilitate transfer of ubiquitin to a protein substrate. The substrate recognition and ubiquitin transfer activities of the E3 ligase may be mediated by a single polypeptide or may rely on separate subunits. The latter organization is particularly prevalent among members of largest class of E3 ligases, the RING family, although examples of this type of arrangement have also been reported among members of the smaller HECT family of E3 ligases. This review describes recent discoveries that reveal the surprising and distinctive ability of VprBP (DCAF1) to serve as a substrate recognition subunit for a member of both major classes of E3 ligase, the RING-type CRL4 ligase and the HECT-type EDD/UBR5 ligase. The cellular processes normally regulated by VprBP-associated E3 ligases, and their targeting and subversion by viral accessory proteins are also discussed. Taken together, these studies provide important insights and raise interesting new questions regarding the mechanisms that regulate or subvert VprBP function in the context of both the CRL4 and EDD/UBR5 E3 ligases.

Aim: To evaluate the technical feasibility of laparoscopic lateral pelvic lymph node dissection (LPLD) following total mesorectal excision (TME) as prophylaxis for patients with advanced lower rectal cancer but no radiologic evidence of lymph node involvement., Patients and Methods: TME was performed on 30 patients with cT3N1-2M0 lower rectal cancer. LPLD was performed by laparoscopic surgery in 12 patients (LAP group),and open surgery in 18 patients (Open group). Statistical analysis was used to compare the number of harvested lymph nodes, operative time, operative blood loss, transfusion rate, and volume of transfusion between the groups., Results: No significant difference was observed in the number of harvested lymph nodes. Operative time was significantly longer in the LAP group; however, operative blood loss, transfusion rate, and volume of transfusion were significantly lower in the LAP group., Conclusion: Laparoscopic LPLD, when performed by a well-trained laparoscopic team, is safe and feasible in some selected lower rectal cancer patients. This approach has the potential to achieve oncologic lymph node clearance equivalent to open surgical LPLD, and to overcome the cited disadvantages of LPLD, which include greater operative blood loss and urinary dysfunction.

CUL4B, encoding a scaffold protein for the assembly of Cullin4B-Ring ubiquitin ligase (CRL4B) complexes, is frequently mutated in X-linked mental retardation (XLMR) patients. Here, we show that CUL4B, but not its paralog, CUL4A, targets WDR5, a core subunit of histone H3 lysine 4 (H3K4) methyltransferase complexes, for ubiquitylation and degradation in the nucleus. Knocking down CUL4B increases WDR5 and trimethylated H3K4 (H3K4me3) on the neuronal gene promoters and induces their expression. Furthermore, CUL4B depletion suppresses neurite outgrowth of PC12 neuroendocrine cells, which can be rescued by codepletion of WDR5. XLMR-linked mutations destabilize CUL4B and impair its ability to support neurite outgrowth of PC12 cells. Our results identify WDR5 as a critical substrate of CUL4B in regulating neuronal gene expression and suggest epigenetic change as a common pathogenic mechanism for CUL4B-associated XLMR., (Copyright © 2011 Elsevier Inc. All rights reserved.)

A 63-year-old woman was admitted to our hospital because of tarry stool several years previously. At the time, café-au-lait spots and dermal nodules were found on her entire body, and a diagnosis of von Recklinghausen disease was established. Small bowel endoscopy revealed a submucosal tumor in the jejunum. Laparotomy was therefore performed on the suspicion of intestinal GIST. Numerous extramural tumors with a diameter of 3-5mm were observed along the jejunum and ileum, in addition to the primary tumor. Partial resection of the jejunum, including the primary tumor and only one small nodule was performed to prevent short bowel syndrome. Immunopathological studies of the tumors were positive for KIT and CD34 and we diagnosed multiple intestinal GISTs. Imatinib mesylate was not administered, but no growth of the residual tumors have been recognized for 10 months after surgery.

Purpose: In the ileum of W/W(v) mutant mice (W/W(v)), the absence of interstitial cells of Cajal (ICC) in the myenteric region (ICC-MY), and cross-talk between ICC in the deep muscular region (ICC-DMP) and enteric nitrergic motor nerves leads to irregular spontaneous electrical and contractile activity. The aim of the present study was to reveal changes in this irregular spontaneous electrical and contractile activity in the ileum of dextran sodium sulfate (DSS: m.w. 40,000)-induced colitis model W/W(v) mice., Methods: Electrical and contractile activity was recorded with a suction electrode and with both an isometric force transducer and a pressure transducer in the ileum of W/W(v) mice either with DSS-induced colitis (DSS (+)) in the distal colon or without in controls (DSS (-)). Neuronal NO synthase (nNOS) and inducible NO synthase (iNOS) immunoreactivity in the ileum was compared between the following groups of mice: W/W(v) DSS (+), W/W(v) DSS (-), wild type (WT) with (DSS (+)) and WT without DSS-induced colitis (DSS (-))., Results: DSS induced colitis in the distal colon of W/W(v) mice is reduced compared with that in WT mice, despite the reduction in the number of mast cells in the W/W(v) mutants. Irregular contractions in the ileum without colitis were strongly suppressed in W/W(v) DSS (+) mice. The mean interval of irregular contractions in W/W(v) DSS (+) mice was 5-fold larger than that in W/W(v) DSS (-) mice. N-nitro-L-arginine methyl ester (L-NAME) facilitated the frequency of irregular contractions in the ileum without colitis in W/W(v) DSS (+) mice. L-NAME decreased the mean interval of contractions to one-fourth in the ileum of W/W(v) DSS (+) mice, where strong iNOS immunoreactivity in nitrergic motor nerves was found with unchanged nNOS immunoreactivity., Conclusions: The stronger suppression of irregular contractions of the ileum in DSS-induced colitis model W/W(v) mice was elicited and mediated by cross-talk between ICC-DMP and enteric nitrergic motor nerves expressing iNOS/NO, even though the ileum was not demonstrating colitis.

Although radiation-induced colonic cancer is thought to arise from dysplasia, no guidelines exist for the treatment of such dysplasia. Therefore, clinicians must make treatment decisions for this condition on a case-by-case basis. Especially when the operative procedure is being decided, it is necessary to consider postoperative quality of life for advanced age. We report a patient who underwent sigmoidectomy for sigmoid colonic dysplasia that developed 35 years after radiation therapy. A 73-year-old woman who had undergone total hysterectomy and chemoradiotherapy for cervical cancer 35 years previously presented following a positive fecal occult blood test. Colonoscopy revealed sigmoid colonic dysplasia. To ensure reliable removal of the lesion, we elected to perform surgical resection. Given the patient's age, we performed sigmoidectomy rather than resecting the entire irradiated intestinal tract. The diagnosis of dysplasia was confirmed based on pathological findings, which included duct proliferation with partial structural atypia.

The interaction of glucocorticoid modulatory element-binding protein 1 (GMEB1) with procaspase-2, -8, or -9 prevents caspase oligomerization and maturation. In the present study, we examined the effect of GMEB1 on neuronal apoptosis induced by hypoxia and oxidative stress. GMEB1 effectively attenuated caspase activation and apoptosis caused by these stresses in human neuroblastoma SK-N-MC cells, indicating that it functions as a potent inhibitor of caspase activation and apoptosis in response to oxidative stress. We propose that GMEB1 blocks pro-apoptosis signals induced by a variety of stresses.

Background: Tumor 'budding' of colorectal carcinoma along the invasive margin has been associated with increased malignant potential. This study investigated the possible prognostic significance of budding in invasive colorectal carcinoma., Patients and Methods: Specimens resected from 149 patients who underwent potentially curative surgery for invasive colorectal carcinoma were studied. Budding was defined according to Ueno's criteria; budding intensity was assessed by examination of hematoxylin-eosin (HE)-stained specimens and immunohistochemical (IHC)-stained specimens using anti-cytokeratin antibody and anti-lymphatic vessel antibody., Results: Immunohistochemical analysis identified many more budding foci that were not detectable by examination of HE-stained specimens. Multivariate analyses revealed that budding identified using immunohistochemical staining was a significant prognostic marker for disease-free survival and there was significant correlation between budding and microlymphatic vessel infiltration at the invasive tumor front., Conclusion: Budding, particularly as assessed with immunohistochemical staining, is a useful predictor of poor prognosis in patients with invasive colorectal carcinoma.

FK506-binding protein 38 (FKBP38) is a member of the immunophilin family that resides in the mitochondrial outer membrane and the endoplasmic reticulum (ER) membrane. To investigate the physiological function of FKBP38, we performed a comprehensive search for proteins with which it interacts in human cells by liquid chromatographic and mass spectrometric analysis of FKBP38 immunoprecipitates. Almost all subunits of the 26S proteasome were thus found to interact with FKBP38. In vivo co-immunoprecipitation analyses confirmed that FKBP38 indeed associates with the 26S proteasome via its three tandem tetratricopeptide repeats (TPRs). Binding assays in vitro also revealed that FKBP38 directly interacts with the S4 subunit of the 19S proteasome. Immunofluorescence analysis demonstrated that the subcellular distributions of FKBP38 and the 26S proteasome partially overlapped at mitochondria. Both the abundance and activity of the proteasome in a membrane fraction were markedly reduced for mouse embryonic fibroblasts prepared from Fkbp38(-/-) mice compared with those prepared from wild-type mice. These results suggest that FKBP38 functions to anchor the 26S proteasome at the organellar membrane.

Fbxw7 (also known as Sel-10, hCdc4 or hAgo) is the F-box protein component of a Skp1-Cul1-F-box protein (SCF) ubiquitin ligase. Fbxw7 contributes to the ubiquitin-mediated degradation of cyclin E, c-Myc, Aurora-A, Notch and c-Jun, all of which appear to function as cell-cycle promoters and oncogenic proteins. Loss of Fbxw7 results in elevated expression of its substrates, which may lead to oncogenesis. However, it remains largely unclear which accumulating substrate is most related to cancer development in Fbxw7-mutant cancer cells. In the present study, we examined the abundance of cyclin E, c-Myc and Aurora-A in seven cancer cell lines, which harbor wild-type (three lines) or mutant (four lines) Fbxw7. Although these three substrates accumulated in the Fbxw7-mutant cells, the extent of increase in the expression of these proteins varied in each line. Forced expression of Fbxw7 reduced the levels of cyclin E, c-Myc and Aurora-A in the Fbxw7-mutant cells. In contrast, a decrease in the expression of cyclin E, c-Myc or Aurora-A by RNA interference significantly suppressed the rate of proliferation and anchorage-independent growth of the Fbxw7-mutant cells. These findings thus suggest that the loss of Fbxw7 results in accumulation of cyclin E, c-Myc and Aurora-A, all of which appear to be required for growth promotion of cancer cells. Fbxw7 seems to regulate the levels of multiple targets to suppress cancer development.

Caspases are divided into two classes: initiator caspases, which include caspase-8 and -9 and possess long prodomains, and effector caspases, which include caspase-3 and -7 and possess short prodomains. Recently, we demonstrated that glucocorticoid modulatory element-binding protein 1 (GMEB1) interacts with the prodomain of procaspase-2, thereby disrupting its autoactivation and the induction of apoptosis. Here we show that GMEB1 is also capable of binding to procaspase-8 and -9. GMEB1 attenuated the Fas-mediated activation of these caspases and the subsequent apoptosis. The knockdown of endogenous GMEB1 using RNA interference revealed that cells with decreased GMEB1 expression are more sensitive to stress and undergo accelerated apoptosis. Transgenic mice expressing a neurospecific GMEB1 had smaller cerebral infarcts and less brain swelling than wild-type mice in response to transient focal ischemia. These results suggest that GMEB1 is an endogenous regulator that selectively binds to initiator procaspases and inhibits caspase-induced apoptosis.

Caspases are the primary executioners of apoptosis. Although procaspases believe to exist as inactive forms in cells, the detailed regulatory system remains unclear. Here we show that glucocorticoid modulatory element-binding protein 1 (GMEB1) is capable of binding to the prodomain of caspase-2. We found that this molecule inhibits the autoproteolytic activation of procaspase-2 by oligomerization on a chemical compound-dependent system. These findings indicated that GMEB1 might be an endogenous inhibitory protein that selectively interacts with prodomain of caspase-2 to disrupt the autoactivation.