Optimizing EUS-guided choledochoduodenostomy with lumen-apposing metal stents for primary drainage of malignant distal biliary obstruction (SCORPION-IIp): a prospective pilot study.

BACKGROUND AND AIMS: Biliary drainage by endoscopic retrograde cholangiography (ERCP) in patients with malignant distal bile duct obstruction (MBO) is frequently associated with complications, such as pancreatitis, hampering patient outcome. EUS-guided choledochoduodenostomy (EUS-CDS) with a lumen-apposing metal stent (LAMS) is a promising alternative in patients with MBO but is associated with a worrisome risk of stent dysfunction. Placement of a fully covered self-expandable metal stent (FCSEMS) through the LAMS, thereby changing the axis of biliary drainage towards the descending duodenum, may decrease the risk of stent dysfunction while maintaining high technical success and low adverse event rates. METHODS: Prospective single center pilot study in patients with a pathology confirmed MBO without gastric-outlet obstruction. Primary outcome was stent dysfunction, defined as recurrent jaundice after initial clinical success, ongoing jaundice in combination with persistent bile duct dilatation, or cholangitis. The study was registered in clinicaltrials.gov (registry number NCT05595122). RESULTS: Overall, 27 consecutive patients eligible for EUS-CDS were enrolled. The placement of a LAMS was successful in 24/27 patients (89%), and placement of FCSEMS through the LAMS was successful in 20/24 (83%), in the remaining 4 patients a coaxial double-pigtail plastic stent was placed. In 2 of these 20 patients there was persistent jaundice requiring stent revision (10%), leading to a clinical success rate of 90%. No patients developed stent dysfunction after initial clinical success. CONCLUSIONS: This study showed a stent dysfunction rate of 10% following technically successful EUS-CDS with placement of a FCSEMS through the LAMS. Improving the design of LAMS may further reduce the rate of stent dysfunction.

Recurrent cholangitis in patients with a non-stenotic hepaticojejunostomy: incidence and risk factors.

BACKGROUND: Cholangitis is a well-known complication after hepaticojejunostomy (HJ), which is mainly caused by a stenotic anastomosis. However, the rate of cholangitis in patients with a non-stenotic (i.e. patent) HJ is unknown. We aimed to evaluate the incidence and risk factors of recurrent cholangitis in patients with a non-stenotic HJ. METHODS: This single-center retrospective cohort study included all consecutive patients who had undergone hepatobiliary or pancreatic (HPB) surgery requiring HJ (2015-2022). Primary outcome was recurrent non-stenotic cholangitis, risk factors for recurrent non-stenotic cholangitis were identified using logistic regression. RESULTS: Overall, 835 patients with a HJ were included of whom 31/698 (4.4%) patients developed recurrent cholangitis with a non-stenotic HJ during a median follow-up of 34 months (IQR 22-50) and 98/796 (12.3%) patients developed a symptomatic HJ stenosis. These 31 patients experienced 205 cholangitis episodes, median 7.0 (IQR 3.8-8.8) per patient, and 71/205 (34.6%) cholangitis episodes required hospitalization. Male sex (aOR 3.17 (95% CI: 1.34-7.49)) and benign disease (aOR 2.97, 95% CI 1.40-6.33) were identified as risk factors for recurrent cholangitis in non-stenotic HJ in both univariate and multivariable analysis. CONCLUSION: This study shows that 4% of patients developed recurrent cholangitis without an underlying HJ stenosis.

Antibiotic Therapy of 3 Days May Be Sufficient After Biliary Drainage for Acute Cholangitis: A Systematic Review.

BACKGROUND: The optimal antibiotic therapy duration for cholangitis is unclear. Guideline recommendations vary between 4 and 14 days after biliary drainage. Clinical observations and some evidence however suggest that shorter antibiotic therapy may be sufficient. OBJECTIVE: To compare the effectiveness and safety of short-course therapy of ≤ 3 days with long-course therapy of ≥ 4 days after biliary drainage in cholangitis patients. METHODS: We searched the databases PubMed, EMBASE, Cochrane Library, and trial registers for literature up to August 5, 2020. RCTs and observational studies including case series reporting on antibiotic therapy duration for acute cholangitis were eligible for inclusion. Two reviewers independently evaluated study eligibility, extracted data, assessed risk of bias and quality of evidence. A meta-analysis was planned if the included studies were comparable with regard to important study characteristics. Primary outcomes included recurrent cholangitis, subsequent other infection, and mortality. RESULTS: We included eight studies with 938 cholangitis patients. Four observational studies enrolled patients treated for ≤ 3 days. Recurrent cholangitis occurred in 0-26.8% of patients treated with short-course therapy, which did not differ from long-course therapy (range 0-21.1%). Subsequent other infection and mortality rates were also comparable. Quality of available evidence was very low. CONCLUSION: There is no high-quality evidence available to draw a strong conclusion, but heterogeneous observational studies suggest that antibiotic therapy of ≤ 3 days is sufficient in cholangitis patients with common bile duct stones.

Sex disparity in colonic adenomagenesis involves promotion by male hormones, not protection by female hormones.

It recently has been recognized that men develop colonic adenomas and carcinomas at an earlier age and at a higher rate than women. In the Apc(Pirc/+) (Pirc) rat model of early colonic cancer, this sex susceptibility was recapitulated, with male Pirc rats developing twice as many adenomas as females. Analysis of large datasets revealed that the Apc(Min/+) mouse also shows enhanced male susceptibility to adenomagenesis, but only in the colon. In addition, WT mice treated with injections of the carcinogen azoxymethane (AOM) showed increased numbers of colonic adenomas in males. The mechanism underlying these observations was investigated by manipulation of hormonal status. The preponderance of colonic adenomas in the Pirc rat model allowed a statistically significant investigation in vivo of the mechanism of sex hormone action on the development of colonic adenomas. Females depleted of endogenous hormones by ovariectomy did not exhibit a change in prevalence of adenomas, nor was any effect observed with replacement of one or a combination of female hormones. In contrast, depletion of male hormones by orchidectomy (castration) markedly protected the Pirc rat from adenoma development, whereas supplementation with testosterone reversed that effect. These observations were recapitulated in the AOM mouse model. Androgen receptor was undetectable in the colon or adenomas, making it likely that testosterone acts indirectly on the tumor lineage. Our findings suggest that indirect tumor-promoting effects of testosterone likely explain the disparity between the sexes in the development of colonic adenomas.

Oestrogens promote tumorigenesis in a mouse model for colitis-associated cancer.

BACKGROUND: Hormone replacement therapy increases the risk of developing ulcerative colitis in postmenopausal women. Chronic intestinal inflammation predisposes to colon cancer development, but effects of female hormones on colitis-associated cancer development have not been examined. AIM: To investigate the role of female hormones in the dextran sodium sulfate (DSS)-azoxymethane (AOM) mouse model for colitis-associated cancer. DESIGN: We performed ovariectomies, or sham operations, on mice, and supplemented these animals with indicated hormones. Additionally, we used oestrogen receptor α or ß (Erα or Erß) mutant mice. To study colitis or colitis-associated cancer, we used DSS only, or DSS and AOM, respectively. RESULTS: Ovariectomy protects female mice against colitis-associated tumour development. Hormone replacement in ovariectomised mice with either oestradiol (E2), medroxyprogesterone acetate or a combination of both suggests that oestrogens are the ovary-derived factor that promotes tumour development in the context of inflammatory damage. E2-treated animals showed increased clinical symptoms and Il-6 production upon DSS-induced colitis and enhanced epithelial proliferation. Treatment with E2 markedly increased the numbers of polyps in ovariectomised mice and also strongly promoted tumour progression with all E2-treated animals developing at least one invasive adenocarcinoma, whereas, placebo-treated animals developed adenomas only. Using Er mutant mice, we find that the protumorigenic effect of oestrogen depends on both Erα and Erß. CONCLUSIONS: Our results suggest that oestrogens promote inflammation-associated cancer development by impairing the mucosal response to inflammatory damage.

Successful endoscopic management of a large esophageal defect due to Boerhaave syndrome with endoscopic vacuum therapy using vacuum sponge and vacuum stent.

Video 1Successful endoscopic management of a large esophageal defect due to Boerhaave syndrome with endoscopic vacuum therapy using EsoSponge and VACStent.

Colorectal tumor prevention by the progestin medroxyprogesterone acetate is critically dependent on postmenopausal status.

The large randomized placebo controlled trials of the Women's Health Initiative have shown that the combination of estrogen and progestin medroxyprogesterone acetate (MPA) protects from colorectal cancer in postmenopausal women. No effect was observed in women treated with estrogen alone. This suggests that progesterone, or more specifically the progestin MPA may have chemopreventive activity. The effect of MPA on colorectal carcinogenesis has been difficult to study in animal models. Most models are not affected by either depleting female hormones by ovariectomy or treatment with MPA. Importantly, an ovariectomy fails to reproduce one of the hall marks of the postmenopausal state in women with intact ovaries. That is, the continued production of androgens by the atrophic postmenopausal ovaries. Here we show that adenoma incidence is increased in the vinyl cylcohexene diepoxide (VCD) mouse model of the menopause compared to age matched fertile female mice. Treatment with MPA protected VCD treated mice from adenomagenesis, but had no effect on adenoma numbers in age-matched fertile female mice. Our data show that the protective effect of MPA depends on the postmenopausal state and suggest that MPA monotherapy may be studied as a chemopreventive agent in postmenopausal women.

Heterozygosity of Chaperone Grp78 Reduces Intestinal Stem Cell Regeneration Potential and Protects against Adenoma Formation.

Deletion of endoplasmic reticulum resident chaperone Grp78 results in activation of the unfolded protein response and causes rapid depletion of the entire intestinal epithelium. Whether modest reduction of Grp78 may affect stem cell fate without compromising intestinal integrity remains unknown. Here, we employ a model of epithelial-specific, heterozygous Grp78 deletion by use of VillinCreERT2-Rosa26ZsGreen/LacZ-Grp78+/fl mice and organoids. We examine models of irradiation and tumorigenesis, both in vitro and in vivo Although we observed no phenotypic changes in Grp78 heterozygous mice, Grp78 heterozygous organoid growth was markedly reduced. Irradiation of Grp78 heterozygous mice resulted in less frequent regeneration of crypts compared with nonrecombined (wild-type) mice, exposing reduced capacity for self-renewal upon genotoxic insult. We crossed mice to Apc-mutant animals for adenoma studies and found that adenomagenesis in Apc heterozygous-Grp78 heterozygous mice was reduced compared with Apc heterozygous controls (1.43 vs. 3.33; P < 0.01). In conclusion, epithelium-specific Grp78 heterozygosity compromises epithelial fitness under conditions requiring expansive growth such as adenomagenesis or regeneration after γ-irradiation. These results suggest that Grp78 may be a therapeutic target in prevention of intestinal neoplasms without affecting normal tissue.Significance: Heterozygous disruption of chaperone protein Grp78 reduces tissue regeneration and expansive growth and protects from tumor formation without affecting intestinal homeostasis. Cancer Res; 78(21); 6098-106. ©2018 AACR.

Stromal Hedgehog signalling is downregulated in colon cancer and its restoration restrains tumour growth.

A role for Hedgehog (Hh) signalling in the development of colorectal cancer (CRC) has been proposed. In CRC and other solid tumours, Hh ligands are upregulated; however, a specific Hh antagonist provided no benefit in a clinical trial. Here we use Hh reporter mice to show that downstream Hh activity is unexpectedly diminished in a mouse model of colitis-associated colon cancer, and that downstream Hh signalling is restricted to the stroma. Functionally, stroma-specific Hh activation in mice markedly reduces the tumour load and blocks progression of advanced neoplasms, partly via the modulation of BMP signalling and restriction of the colonic stem cell signature. By contrast, attenuated Hh signalling accelerates colonic tumourigenesis. In human CRC, downstream Hh activity is similarly reduced and canonical Hh signalling remains predominantly paracrine. Our results suggest that diminished downstream Hh signalling enhances CRC development, and that stromal Hh activation can act as a colonic tumour suppressor.

ER-Stress-Induced Differentiation Sensitizes Colon Cancer Stem Cells to Chemotherapy.

Colon cancer stem cells (colon-CSCs) are more resistant to conventional chemotherapy than differentiated cancer cells. This subset of therapy refractory cells is therefore believed to play an important role in post-therapeutic tumor relapse. In order to improve the rate of sustained response to conventional chemotherapy, development of approaches is warranted that specifically sensitize colon-CSCs to treatment. Here, we report that ER-stress-induced activation of the unfolded protein response (UPR) forces colon-CSCs to differentiate, resulting in their enhanced sensitivity to chemotherapy in vitro and in vivo. Our data suggest that agents that induce activation of the UPR may be used to specifically increase sensitivity of colon-CSCs to the effects of conventional chemotherapy.

Azathioprine does not reduce adenoma formation in a mouse model of sporadic intestinal tumorigenesis.

AIM: To investigate if azathioprine could reduce adenoma formation in Apc(Min/+) , a mouse model of sporadic intestinal tumorigenesis. METHODS: Azathioprine was administered via drinking water (estimated 6-20 mg/kg body weight per day) to Apc(Min/+) and wildtype mice. Control animals received vehicle only (DMSO) dissolved in drinking water. At 15 wk of age all mice were sacrificed and intestines of Apc(Min/+) were harvested for evaluation of polyp number. Azathioprine induced toxicity was investigated by immunohistochemical analysis on spleens. RESULTS: All azathioprine treated mice showed signs of drug-associated toxicity such as weight loss and development of splenic T-cell lymphomas. Although this suggests that the thiopurine concentration was clearly in the therapeutic range, it did not reduce tumor formation (48 ± 3.1 adenomas vs 59 ± 5.7 adenomas, P = 0.148). CONCLUSION: We conclude that in the absence of inflammation, azathioprine does not affect intestinal tumorigenesis.

ER stress causes rapid loss of intestinal epithelial stemness through activation of the unfolded protein response.

Stem cells generate rapidly dividing transit-amplifying cells that have lost the capacity for self-renewal but cycle for a number of times until they exit the cell cycle and undergo terminal differentiation. We know very little of the type of signals that trigger the earliest steps of stem cell differentiation and mediate a stem cell to transit-amplifying cell transition. We show that in normal intestinal epithelium, endoplasmic reticulum (ER) stress and activity of the unfolded protein response (UPR) are induced at the transition from stem cell to transit-amplifying cell. Induction of ER stress causes loss of stemness in a Perk-eIF2α-dependent manner. Inhibition of Perk-eIF2α signaling results in stem cell accumulation in organoid culture of primary intestinal epithelium. Our findings show that the UPR plays an important role in the regulation of intestinal epithelial stem cell differentiation.