Local excision versus radical surgery for anal squamous cell carcinoma: a multicenter study in Japan.

BACKGROUND: The standard treatment for anal squamous cell carcinoma is chemoradiation therapy (CRT), but there is a possibility of over-treatment for early-stage disease. cTisN0 and cT1N0 disease is currently indicated for local excision, but it is unclear whether the indication of local excision can be expanded to cT2N0 disease. METHODS: 126 patients with cTis-T2N0 anal cancer treated at 47 centers in Japan between 1991 and 2015 were included. Patients were first classified into the CRT group and surgical therapy group according to the initial therapy, and the latter was further divided into local excision (LE) and radical surgery (RS) groups. We compared prognoses among the groups, and analyzed risk factors for recurrence after local excision. RESULTS: The CRT group (n = 87) and surgical therapy group (n = 39) showed no difference in relapse-free survival (p = 0.29) and overall survival (p = 0.94). Relapse-free survival curves in the LE (n = 23) and RS groups (n = 16) overlapped for the initial 3 years, but the curve for the LE group went lower beyond (p = 0.33). By contrast, there was no difference in overall survival between the two groups (p = 0.98). In the LE group, the majority of recurrences distributed in locoregional areas, which could be managed by salvage treatments. Muscular invasion was associated with recurrence after local excision (hazard ratio: 22.91, p = 0.011). CONCLUSION: LE may be applied to selected patients with anal cancer of cTis-T2N0 stage. Given the high risk of recurrence in cases with muscular invasion, it may be important to consider close surveillance and additional treatment in such patients.

Preoperative Simulation of Ileal Pouch-Anal Anastomosis in Patients With Ulcerative Colitis Using a 3-Dimensional Printed Model.

BACKGROUND: During restorative proctocolectomy with ileal pouch-anal anastomosis for ulcerative colitis-associated colorectal cancer or dysplasia, ileal pouch-anal handsewn anastomosis (IAA) is preferred to avoid the risk of cancer development in the remaining rectal mucosa. However, there is a risk of the ileal pouch not reaching the anus with this procedure. Here, we created deformable 3-dimensional (3D) models for simulation. METHOD: Six patients who underwent IAA without vessel ligation and 5 patients who underwent ileal pouch-anal canal double-stapled anastomosis (IACA) because the ileal pouch did not reach the anus were studied. A 3D printer was used to create deformable 3D models from the data obtained from computed tomography scans. The positional relationship among the mesenteric arteries, pubis, and coccyx were evaluated. RESULT: The distance between the superior mesenteric artery root and the tip of the ileal artery was longer in the IAA group than that in the IACA group (IAA vs IACA: 26.2 ±â€…2.1 cm vs 20.9 ±â€…1.6cm). The distance from the tip of the ileal artery to the coccyx (IAA vs IACA: 6.7 ±â€…1.7 cm vs 12.1 ±â€…2.1 cm) and the distance from the tip of the ileal artery to the lower edge of the pubis (IAA vs IACA; 8.1 ±â€…1.3 cm vs 12.7 ±â€…2.4 cm) were longer in the IACA group than those in the IAA group. CONCLUSIONS: We established a method for creating 3D deformable models of patients with ileal pouch-anal anastomosis. These 3D models may be useful for preoperative simulation.

We established the method for creating deformable 3-dimensional models of the patients who underwent restorative proctocolectomy with ileal pouch­anal anastomosis, and the distance from the tip of the ileal artery to the coccyx was shorter in ileal pouch­anal handsewn anastomosis group.

Determination of the positional relationship of the second Houston valve and peritoneal reflection using computed tomographic colonography and magnetic resonance imaging.

PURPOSE: The second Houston valve is used as a surrogate for estimating the position of the peritoneal reflection; however, the concordance between the positions of the valve and peritoneal reflection has not been investigated. This study aimed to clarify this positional relationship. METHODS: The second Houston valve and peritoneal reflection positions were assessed using tomographic colonography and magnetic resonance imaging. In total, 117 patients were enrolled in this study. RESULTS: The positions of the second Houston valve and peritoneal reflection were nearly concordant, although the space between them ranged from - 20.7 to 33.9 mm. A peritoneal reflection located further from the anal verge than the second Houston valve was defined as a shallow peritoneal reflection. Male sex, high body weight, and a high body mass index were significantly correlated with a shallower peritoneal reflection, as determined by a univariate analysis (sex: P = 0.0138, weight: P = 0.0097, body mass index: P = 0.0311). A multivariate analysis revealed a significantly shallower peritoneal reflection in males than in females (odds ratio: 2.75, 95% confidence interval: 1.15-6.56, P = 0.023). CONCLUSIONS: The second Houston valve located near the peritoneal reflection can be a useful surrogate marker for estimating its position. In relatively heavy males, the peritoneal reflection is located more cranially than the second Houston valve.

Computed tomographic colonography versus double-contrast barium enema for the preoperative evaluation of rectal cancer.

PURPOSE: We investigated whether or not computed tomographic colonography (CTC) is a viable alternative to double-contrast barium enema (BE) for a preoperative rectal cancer evaluation. METHODS: The size and distance from the anal canal to the lower or upper tumor borders were laterally measured in 147 patients who underwent CTC and BE. Measurements were grouped into early cancer, advanced, and after chemoradiation therapy (CRT). RESULTS: In the early and advanced cancer groups, all lesions were visualized by BE. In contrast, 3 (7.8%) early and 8 (7.3%) advanced cases, located at the anterior wall near the anal canal, were not visualized by CTC because of liquid level formation. In the CRT group, 16 (23.5%) and 4 (5.8%) cases were not visualized by CTC and BE, respectively. The BE and CTC size measurements were similar among cohorts. However, the distance from the anal canal's superior margin tended to be longer with BE, especially in early cancer. The differences in distance from the anal canal were significantly larger in the early cancer group than in the other two groups (p = 0.0024). CONCLUSION: CTC may be a viable alternative imaging modality in some cases. However, BE should be employed in anterior wall cases near the anal canal and CRT cases.

MIND bomb 2 prevents RIPK1 kinase activity-dependent and -independent apoptosis through ubiquitylation of cFLIPL.

Mind bomb 2 (MIB2) is an E3 ligase involved in Notch signalling and attenuates TNF-induced apoptosis through ubiquitylation of receptor-interacting protein kinase 1 (RIPK1) and cylindromatosis. Here we show that MIB2 bound and conjugated K48- and K63-linked polyubiquitin chains to a long-form of cellular FLICE-inhibitory protein (cFLIPL), a catalytically inactive homologue of caspase 8. Deletion of MIB2 did not impair the TNF-induced complex I formation that mediates NF-κB activation but significantly enhanced formation of cytosolic death-inducing signalling complex II. TNF-induced RIPK1 Ser166 phosphorylation, a hallmark of RIPK1 death-inducing activity, was enhanced in MIB2 knockout cells, as was RIPK1 kinase activity-dependent and -independent apoptosis. Moreover, RIPK1 kinase activity-independent apoptosis was induced in cells expressing cFLIPL mutants lacking MIB2-dependent ubiquitylation. Together, these results suggest that MIB2 suppresses both RIPK1 kinase activity-dependent and -independent apoptosis, through suppression of RIPK1 kinase activity and ubiquitylation of cFLIPL, respectively.

Identification of the hallmarks of necroptosis and ferroptosis by transmission electron microscopy.

Apoptosis is the prototype for a regulated form of cell death, but recent studies have revealed other types of regulated forms of cell death, including necroptosis and ferroptosis. The molecular mechanisms underlying the execution of these processes have been intensively investigated, yet the hallmarks of their morphology are not fully understood. Here, we report that electron lucent cytoplasm was a common feature of both necroptosis and ferroptosis, which was consistent with cytoplasmic vacuolization due to a defect in the cytoplasmic membrane integrity. Notably, the perinuclear space was dilated in necroptosis, but such dilation did not occur in ferroptosis. Cells undergoing ferroptosis, but not necroptosis, exhibited an electron lucent nucleus. We previously reported that one of the nuclear danger-associated molecular patterns (DAMPs), high mobility group box (HMGB)1, is rapidly released from the nucleus to the extracellular spaces of cells undergoing necroptosis through the ruptured nuclear and cytoplasmic membrane. Via time-lapse imaging of cells stably expressing HMGB1 fused to a fluorescence protein, we found that HMGB1 was also released from the nucleus to the cytosol, and then eventually released into the extracellular spaces in cells undergoing ferroptosis. Thus, nuclear membrane damage was induced prior to cytoplasmic membrane rupture in ferroptosis. Thus, dilation of the perinuclear space and an electron lucent nucleus may be the hallmarks of necroptosis and ferroptosis, respectively.

Laparoscopic treatment of a vesicointestinal fistula due to a Meckel's diverticulum: a case report and review of the literature.

While there have been numerous reports about colovesical fistulas and ruptured intestinal diverticula, there have been far fewer reports about vesicointestinal fistulas caused by Meckel's diverticula. Most Meckel's diverticula are asymptomatic. Furthermore, they seldom cause vesicointestinal fistulas, and the associated complications are non-specific. Thus, their preoperative diagnosis is difficult. We experienced a case in which a vesicointestinal fistula was caused by a Meckel's diverticulum and was treated with laparoscopic surgery. A 46-year-old male was referred to our hospital after exhibiting hematuria. Cystoscopy revealed a fistula between the small intestine and bladder. Contrast-enhanced computed tomography and magnetic resonance imaging showed a diverticulum in the ileum and a fistula between the ileum and bladder, which passed through the diverticulum. A Meckel's diverticulum was suspected. We conducted a laparoscopic operation. We dissected the Meckel's diverticulum with an automatic suturing device and removed it together with part of the ileum. The patient's postoperative course was good. We experienced a case in which a vesicointestinal fistula was caused by a Meckel's diverticulum and was successfully treated with laparoscopic surgery. In selected cases of Meckel's diverticulum, the dissection of the diverticulum with an automatic suturing device is appropriate.

Novel method to rescue a lethal phenotype through integration of target gene onto the X-chromosome.

The loss-of-function mutations of serine protease inhibitor, Kazal type 1 (SPINK1) gene are associated with human chronic pancreatitis, but the underlying mechanisms remain unknown. We previously reported that mice lacking Spink3, the murine homologue of human SPINK1, die perinatally due to massive pancreatic acinar cell death, precluding investigation of the effects of SPINK1 deficiency. To circumvent perinatal lethality, we have developed a novel method to integrate human SPINK1 gene on the X chromosome using Cre-loxP technology and thus generated transgenic mice termed "X-SPINK1". Consistent with the fact that one of the two X chromosomes is randomly inactivated, X-SPINK1 mice exhibit mosaic pattern of SPINK1 expression. Crossing of X-SPINK1 mice with Spink3+/- mice rescued perinatal lethality, but the resulting Spink3-/-;XXSPINK1 mice developed spontaneous pancreatitis characterized by chronic inflammation and fibrosis. The results show that mice lacking a gene essential for cell survival can be rescued by expressing this gene on the X chromosome. The Spink3-/-;XXSPINK1 mice, in which this method has been applied to partially restore SPINK1 function, present a novel genetic model of chronic pancreatitis.

Apoptosis-inhibiting activities of BIR family proteins in Xenopus egg extracts.

In many animal species including Xenopus, ovulated eggs possess an intrinsic apoptotic execution system. This program is inhibited for a limited time by some maternal apoptosis inhibitors, although their molecular properties remain uncharacterized. Baculovirus IAP repeat (BIR) family proteins contain evolutionarily conserved BIR domains and play important roles in apoptosis suppression, and are therefore good candidates as maternal apoptosis inhibitors. We identified four maternal BIR family proteins in Xenopus eggs and, using the biochemical advantages of egg extracts, examined their physiological functions. These molecules included two survivin-related proteins, xEIAP/XLX, and a possible ortholog of XIAP named xXIAP. The addition of recombinant xXIAP greatly delayed apoptotic execution, whereas the immunodepletion of endogenous xXIAP significantly accelerated the onset of apoptosis. In contrast, xEIAP/XLX was a poor apoptosis inhibitor, and neither of the survivin orthologs showed anti-apoptotic activity in our assay. Both xEIAP/XLX and xXIAP were degraded by activated caspases, and also by a novel proteolytic system that required the presence of C-terminal RING finger domain but was insensitive to proteasome inhibition. Our data suggest that the regulation of endogenous xXIAP concentration is important for the survival of Xenopus eggs.