MUC13 protects colorectal cancer cells from death by activating the NF-κB pathway and is a potential therapeutic target.

MUC13 is a transmembrane mucin glycoprotein that is over produced by many cancers, although its functions are not fully understood. Nuclear factor-κB (NF-κB) is a key transcription factor promoting cancer cell survival, but therapeutically targeting this pathway has proved difficult because NF-κB has pleiotropic functions. Here, we report that MUC13 prevents colorectal cancer cell death by promoting two distinct pathways of NF-kB activation, consequently upregulating BCL-XL. MUC13 promoted tumor necrosis factor (TNF)-induced NF-κB activation by interacting with TNFR1 and the E3 ligase, cIAP1, to increase ubiquitination of RIPK1. MUC13 also promoted genotoxin-induced NF-κB activation by increasing phosphorylation of ATM and SUMOylation of NF-κB essential modulator. Moreover, elevated expression of cytoplasmic MUC13 and NF-κB correlated with colorectal cancer progression and metastases. Our demonstration that MUC13 enhances NF-κB signaling in response to both TNF and DNA-damaging agents provides a new molecular target for specific inhibition of NF-κB activation. As proof of principle, silencing MUC13 sensitized colorectal cancer cells to killing by cytotoxic drugs and inflammatory signals and abolished chemotherapy-induced enrichment of CD133+ CD44+ cancer stem cells, slowed xenograft growth in mice, and synergized with 5-fluourouracil to induce tumor regression. Therefore, these data indicate that combining chemotherapy and MUC13 antagonism could improve the treatment of metastatic cancers.

Elevated CDCP1 predicts poor patient outcome and mediates ovarian clear cell carcinoma by promoting tumor spheroid formation, cell migration and chemoresistance.

Hematogenous metastases are rarely present at diagnosis of ovarian clear cell carcinoma (OCC). Instead dissemination of these tumors is characteristically via direct extension of the primary tumor into nearby organs and the spread of exfoliated tumor cells throughout the peritoneum, initially via the peritoneal fluid, and later via ascites that accumulates as a result of disruption of the lymphatic system. The molecular mechanisms orchestrating these processes are uncertain. In particular, the signaling pathways used by malignant cells to survive the stresses of anchorage-free growth in peritoneal fluid and ascites, and to colonize remote sites, are poorly defined. We demonstrate that the transmembrane glycoprotein CUB-domain-containing protein 1 (CDCP1) has important and inhibitable roles in these processes. In vitro assays indicate that CDCP1 mediates formation and survival of OCC spheroids, as well as cell migration and chemoresistance. Disruption of CDCP1 via silencing and antibody-mediated inhibition markedly reduce the ability of TOV21G OCC cells to form intraperitoneal tumors and induce accumulation of ascites in mice. Mechanistically our data suggest that CDCP1 effects are mediated via a novel mechanism of protein kinase B (Akt) activation. Immunohistochemical analysis also suggested that CDCP1 is functionally important in OCC, with its expression elevated in 90% of 198 OCC tumors and increased CDCP1 expression correlating with poor patient disease-free and overall survival. This analysis also showed that CDCP1 is largely restricted to the surface of malignant cells where it is accessible to therapeutic antibodies. Importantly, antibody-mediated blockade of CDCP1 in vivo significantly increased the anti-tumor efficacy of carboplatin, the chemotherapy most commonly used to treat OCC. In summary, our data indicate that CDCP1 is important in the progression of OCC and that targeting pathways mediated by this protein may be useful for the management of OCC, potentially in combination with chemotherapies and agents targeting the Akt pathway.

EGF inhibits constitutive internalization and palmitoylation-dependent degradation of membrane-spanning procancer CDCP1 promoting its availability on the cell surface.

Many cancers are dependent on inappropriate activation of epidermal growth factor receptor (EGFR), and drugs targeting this receptor can improve patient survival, although benefits are generally short-lived. We reveal a novel mechanism linking EGFR and the membrane-spanning, cancer-promoting protein CDCP1 (CUB domain-containing protein 1). Under basal conditions, cell surface CDCP1 constitutively internalizes and undergoes palmitoylation-dependent degradation by a mechanism in which it is palmitoylated in at least one of its four cytoplasmic cysteines. This mechanism is functional in vivo as CDCP1 is elevated and palmitoylated in high-grade serous ovarian tumors. Interestingly, activation of the EGFR system with EGF inhibits proteasome-mediated, palmitoylation-dependent degradation of CDCP1, promoting recycling of CDCP1 to the cell surface where it is available to mediate its procancer effects. We also show that mechanisms inducing relocalization of CDCP1 to the cell surface, including disruption of its palmitoylation and EGF treatment, promote cell migration. Our data provide the first evidence that the EGFR system can function to increase the lifespan of a protein and also promote its recycling to the cell surface. This information may be useful for understanding mechanisms of resistance to EGFR therapies and assist in the design of treatments for EGFR-dependent cancers.

Surgical outcomes in steroid refractory acute severe ulcerative colitis: the impact of rescue therapy.

AIM: The advent of rescue medical therapy (cyclosporin or infliximab) and laparoscopic surgery has shifted the paradigm in managing steroid refractory acute severe ulcerative colitis (ASUC). We investigated prospectively the impact of rescue therapy on timing and postoperative complications of urgent colectomy and subsequent restorative surgery for steroid refractory ASUC. METHOD: All consecutive presentations of steroid refractory ASUC at the Royal Brisbane Hospital (1996-2009) were entered in the study. Data collated included demographics, clinical and laboratory parameters on admission, medical therapy and operative and postoperative details. Steroid refractory ASUC patients undergoing immediate colectomy were compared with those failing rescue therapy and requiring same admission colectomy. RESULTS: Of 108 steroid refractory ASUC presentations, 19 (18%) received intravenous steroids only and proceeded directly to colectomy. Rescue medical therapy was instituted in 89 (82%) patients with 30 (34%) failing to respond and proceeding to colectomy. There was no significant difference in the median time from admission to colectomy for rescue therapy compared with steroid-only cases (12 vs 10 days, P = 0.70) or 30-day complication rates (27%vs 47%, P = 0.22). The interval from colectomy to a subsequent restorative procedure was significantly longer for patients who failed rescue therapy (12 vs 5 months, P = 0.02). Furthermore 30-day complications following pouch surgery were significantly higher in patients who failed rescue therapy (32%vs 0%, P = 0.01). CONCLUSION: Rescue therapy in steroid refractory ASUC is not related to delay in urgent colectomy or increased post-colectomy complications.

The ideal ileal-pouch design: a long-term randomized control trial of J- vs W-pouch construction.

BACKGROUND: The IPAA has become established as the preferred technique for restoring intestinal continuity postproctocolectomy. The ideal pouch design has not been established. W-pouches may give better functional results owing to increased volume, whereas the J-pouch's advantage is its straightforward construction. We report short- and long-term results of an randomized control trial designed to establish the ideal pouch. DESIGN: Ninety-four patients were randomly assigned to J- and W-pouches (49:45) and assessed at 1 and 8.7 years postoperatively. Assessment was questionnaire based and designed to assess pouch function and patient quality of life. RESULTS: Eighty-five percent of patients were followed up at 1 year, and 68% were followed up at 8.7 years. At 1 year, there was a significant difference in 24-hour bowel movement frequency J- vs W-pouches 7 vs 5(p < 0.001) and in daytime frequency J- vs W-pouches 6 vs 4 (p < 0.001), with no difference in nocturnal function. At 9-year follow-up, function had equilibrated between the 2 groups: 24-hour bowel movement frequency J- vs W-pouches 6.5 vs 6 (p = 0.36), daytime frequency 5.5 vs 5 (p = 0.233), and nocturnal function 1 vs 1 (p = 0.987). Mean operating time of J- and W-pouches was 195 and 215 minutes (p < 0.05). All other parameters, pad usage, urgency, incontinence, and quality of life, did not differ significantly between groups. CONCLUSION: These data demonstrate that the theoretical functional advantage conferred on the W-pouch by its greater volume exists only in the short term and is of little consequence to patients' long-term quality of life. This advantage is attenuated as the pouches mature, resulting in no disparity in pouch function. This, combined with the more consistent, efficient, and easily taught construction of the J-pouch, should conclusively establish it as the optimum ileal-pouch design.

Laparoscopic resection of advanced colorectal cancer.

BACKGROUND: Palliative resection of the primary tumour in asymptomatic patients with stage IV colorectal cancer is associated with improved survival and fewer complications. Laparoscopic surgery is widely employed in the curative treatment of colorectal cancer, but its value in advanced colorectal cancer remains unclear. METHODS: All patients who underwent laparoscopic resection of primary colorectal cancer in this unit between June 1991 and Jan 2010 were entered into a prospective computerized database. Outcomes for patients with laparoscopic resection of stage IV colorectal cancer were compared with those of patients who had laparoscopic surgery for stage I disease. RESULTS: Some 185 patients with stage IV colorectal cancer who underwent laparoscopic resection were compared with 310 patients who had stage I colorectal cancer. Some 94·1 and 98·4 per cent of operations respectively were completed laparoscopically. Hospital stay was slightly longer in the group with stage IV disease (mean 6·2 versus 5·3 days; P = 0·091). The 30-day mortality rate was 2·7 per cent in patients with stage IV disease and 0·6 per cent in those with stage I tumours (P = 0·061). There was no difference in complications. One-year survival rates were 77·8 and 99·0 per cent respectively (P < 0·001). CONCLUSION: Short-term outcomes after laparoscopic surgery for stage IV colorectal cancer in selected patients are equivalent to those for stage I cancers.

Preservation of sexual and bladder function after laparoscopic rectal surgery.

BACKGROUND: There have recently been reports of higher levels of bladder and sexual dysfunction in men after laparoscopic rectal surgery when compared with those undergoing open surgery. This has led some surgeons to question the role of the laparoscopic approach to rectal surgery. METHOD: This study represents a retrospective analysis of a prospectively collected database for a single unit, comprising 2406 patients undergoing laparoscopic colorectal surgery. Bladder function, potency and ejaculation were assessed at postoperative clinic visits for men undergoing laparoscopic low or ultra-low anterior resection and abdominoperineal excision of the rectum. RESULTS: A total of 101 males were identified (median age 62 years: range 20-90 years). Urinary dysfunction was reported by six (6%) patients. Six (6%) patients had sexual dysfunction, manifesting as retrograde ejaculation in four patients and erectile dysfunction in a further two patients. CONCLUSIONS: The low rates of sexual dysfunction in this unit may be attributable to pelvic dissection only being undertaken by experienced, dedicated laparoscopic colorectal surgeons. Laparoscopic restorative surgery for rectal cancer has been performed here only since 2001 after considerable experience accrued in operating on benign rectal disease and colon cancer. Studies from elsewhere reporting poorer functional outcomes have probably included a significant number of patients on the surgeons''learning curve'.

Hypothermia in open and laparoscopic colorectal surgery.

PURPOSE: Perioperative hypothermia has been shown to be an important determinant of outcome after open colorectal resections. The degree of hypothermia occurring with laparoscopic-assisted colorectal surgery is, however, unknown, and the effectiveness of standard warming measures is untested. This study was designed to assess hypothermia in open and laparoscopic-assisted colonic resections using a standardized warming protocol. METHODS: A prospective, nonrandomized study was performed with temperature measurements recorded every ten minutes. Statistical analysis was based on repeated measures analysis of variance models with significance set at the conventional 95 percent (two tailed). RESULTS: A total of 107 patients were entered into the trial; 68 had open and 39 had laparoscopic colectomies. The groups were well matched for age, weight, and duration of surgery, with a median operating time of 180 minutes in each group. The average drop in temperature from commencement of surgery to lowest point was 0.68 degrees C (standard deviation, 0.08) in the open group, compared with 0.53 degrees C (standard deviation, 0.06) in the laparoscopic group (P = 0.126). CONCLUSIONS: Laparoscopic-assisted colorectal surgery is not associated with a higher incidence of perioperative hypothermia than open colorectal surgery using a standard warming regimen for both groups. On the basis of these results, standard temperature conservation is adequate, even for long, complex laparoscopic procedures.

Laparoscopically assisted colorectal surgery in the elderly.

INTRODUCTION: Open colorectal surgery in elderly patients is associated with increased morbidity and mortality rates compared with those in younger age groups. It also requires more intensive postoperative support, longer hospitalization, and in many cases leads to prolonged rehabilitation or institutionalization. Because of its less invasive nature, laparoscopically assisted colorectal surgery may lead to a reduced period of convalescence. However, the safety of advanced laparoscopic surgical techniques in the elderly has not been established, so this prospective comparative study was undertaken. METHODS: All patients aged 80 years or more who were undergoing an elective laparoscopic or open colorectal procedure between 1 January 1992 and 30 June 1997 were assessed prospectively. Patients having simple stoma formation were excluded. Perioperative care, operative results and subsequent function were analysed. RESULTS: There were 42 patients in the laparoscopic group and 35 in the open group, with a median age of 84 years in each group. Five patients undergoing laparoscopic surgery required conversion to an open procedure. No complications related to laparoscopy occurred. Three patients died after operation in the laparoscopic group and four in the open group, with morbidity in seven and 15 patients respectively. Median hospital stay was 9 (range 4-21) days for patients having the laparoscopic operation, and 17 (range 7-28) days in the open cases. At 4 weeks after operation 30 of the 35 independent patients surviving the operation in the laparoscopic group and 16 of 28 in the open group were back to preoperative activity levels. CONCLUSION: In this series laparoscopically assisted colorectal surgery was safe and was associated with a low incidence of complications, short hospitalization and a rapid return to preoperative activity levels when compared with open colorectal resections in this age group.

Laparoscopically assisted anterior resection for diverticular disease: follow-up of 100 consecutive patients.

PURPOSE: The objectives of this study were to refine the technique of laparoscopically assisted anterior resection (LAR) for diverticular disease and to analyze the morbidity and mortality rates, and longer term follow-up of the first 100 consecutive patients. METHODS: Data were collected prospectively, and follow-up was performed by an independent assessor using a standardized questionnaire. RESULTS: The median duration of surgery was 180 minutes, the median time for passage of flatus was 2 days after surgery, and the median length of hospital stay was 4 days. Overall, the morbidity rate was 21%, and the wound infection rate was 5%. There were no deaths. Eight patients underwent open laparotomy. The rate of complications was significantly greater in the latter group of patients (75%) than in those who underwent laparoscopy (16%, p = 0.002). The comparison between the first 20 cases and the last 20 patients revealed a significantly shorter duration of surgery (median 225 min. vs. 150 min.; p < 0.0001) and decreased length of stay (6 days vs. 4 days, p < 0.0001). Apart from a nonsignificant increase in the length of surgery, there were no differences in other study parameters when comparisons were made between those patients who underwent LAR for complicated diverticular disease and those patients who underwent uncomplicated diverticular disease. FOLLOW-UP: Ninety patients were available for follow-up at a median time of 37 months. Ninety-three percent of the patients reported that the surgery had improved their symptoms. No patient required hospitalization, and no one was treated with antibiotics for recurrent symptoms. CONCLUSION: Laparoscopically assisted anterior resection for diverticular disease has acceptable morbidity and mortality rates and a median postoperative hospital stay of only 4 days. Follow-up investigations revealed no recurrence of diverticulitis, and patients reported satisfaction regarding cosmetic and functional results.

Laparoscopic-assisted resection-rectopexy for rectal prolapse: early and medium follow-up.

PURPOSE: Objectives of this study were to describe the technique of laparoscopic-assisted resection rectopexy and audit the clinical outcomes, including review of functional results. METHODS: Data were prospectively collected for duration of operation, time to passage of flatus and feces postoperatively, hospital stay, morbidity, and mortality. Follow-up was performed by an independent assessor using a standardized questionnaire. Patients were also assessed by clinical review or telephone interview. RESULTS: During a four-year period, 34 patients underwent laparoscopic repair for rectal prolapse, of which 30 patients underwent laparoscopic-assisted resection rectopexy. Median duration of the operations was 185 minutes, median time for passage of flatus was two days postoperatively, and median length of hospital stay was five days. Morbidity was 13 percent and mortality rate was 3 percent. Comparison between the first ten patients who underwent laparoscopic-assisted resection rectopexy and the last ten revealed a significant reduction in both median duration of operating time (224 vs. 163 minutes; P < 0.005) and length of stay (6 vs. 4 days; P < 0.015). Follow-up study conducted at a median time of 18 months revealed that most patients (92 percent) felt that the operation had improved their symptoms, that incontinence was improved in 14 of 20 patients with impaired continence (70 percent), and that constipation was improved in 64 percent. Symptoms of incomplete emptying and the need to strain at stool were both improved in 62 and 59 percent of patients, respectively. No full-thickness recurrences have occurred, but two patients have had mucosal prolapse detected (7 percent) and treated. CONCLUSION: Laparoscopic-assisted resection rectopexy is feasible and safe, with acceptable recurrence rates and functional results compared with the open procedure in the surgical literature. There is rapid return of intestinal function associated with an early discharge from hospital.

Laparoscopic colorectal surgery--new advances and techniques.

Laparoscopic colorectal surgery is being assessed in many centres worldwide. This paper looks at the authors' experiences of 320 laparoscopic colorectal procedures and discusses modifications of technique, new instruments and changes in outcomes as experience is attained. Operating times are now approaching that of open surgery as the "learning curve" levels out. For example, the median operating time for the last 20 patients undergoing a laparoscopic right hemicolectomy was 2.1 hours and anterior resection was 2.2 hours. Of the 320 laparoscopic colorectal procedures performed, the conversion rate of 8.1% (26 patients) and perioperative death rate of 2.2% (7 patients) appear to be acceptable for the extent of surgery performed. The median inpatient stay for the last 20 patients undergoing a laparoscopic-assisted right hemicolectomy or high anterior resection was 5 days (range 3 to 11 days) and 4 days (range 3 to 18 days) respectively. Outcomes for cancer patients are encouraging. Of 106 selected patients having a potentially curative resection for colorectal and anal cancer, there have been 10 recurrences (9.4%) to date. Sixty-four patients have now been followed-up for more than 2 years. It is our belief that with appropriate patient selection a laparoscopic approach can give outcomes similar to open surgery with a slightly decreased hospital stay and convalescence. Laparoscopic colorectal surgery, particularly for benign disease, should be encouraged.

Laparoscopic-assisted colorectal surgery. Lessons learned from 240 consecutive patients.

PURPOSE: To audit the development and outcomes of laparoscopic colorectal surgery at the Royal Brisbane Hospital. METHODS: Since July 1991, laparoscopic-assisted colectomy for benign and malignant colorectal disease has been performed on more than 300 patients at the Royal Brisbane Hospital. This paper summarizes the outcome for the first 240 patients who underwent a laparoscopic colorectal procedure. All laparoscopic data were collected prospectively, and for selected studies, data were compared with open surgical controls. RESULTS: Nineteen patients required open conversion (7.9 percent). There was a significant decrease in wound infection rates in patients having a laparoscopic-assisted colectomy (3.6 percent) compared with historical controls (7.9 percent) (P < 0.05; chi-squared). There were five anastomotic leaks, five laparotomies for postoperative adhesive obstruction, and four perioperative deaths. A total of 103 patients had a procedure for colorectal cancer. Of the 79 potentially curative procedures, there have been 5 (6.3 percent) recurrences to date. CONCLUSION: The overall morbidity and mortality in this series seem to be acceptable compared with that of open procedures.

Single dose ceftriaxone as prophylaxis for sepsis in colorectal surgery.

During the period May 1986 to July 1989, a prospective, double blind, randomized trial of antibiotic prophylaxis in colorectal surgery was undertaken at the Royal Brisbane Hospital. Three hundred and thirty patients were considered eligible for the trial. Three regimens were compared: a combination of 2 g ceftriaxone and 1 g metronidazole; a single dose of 2 g ceftriaxone; or 1 g cefazolin and 1 g metronidazole, as antibacterial prophylaxis in colorectal surgery. Fifty patients were excluded from analysis. The overall incidence of wound sepsis was 7.9% (22 patients). There was no statistical difference in the incidence of wound infections between the three groups. The presence of drains and the non-performance of a bowel anastomosis at the time of surgery predisposed patients to wound infection. Staphylococcus aureus or Staphylococcus epidermidis were the cause of wound infection in 16 cases. Patients in the cefazolin and metronidazole group had a significantly higher number of postoperative urinary tract and respiratory tract infections than the other two groups combined (P less than 0.01). There did not appear to be any change in sensitivity patterns to ceftriaxone during the 3 year trial. During the 3 year period of the study, ceftriaxone was found to be a safe and effective drug in antibacterial prophylaxis in colorectal surgery.

Crohn's disease and anal carcinoma: an association? A case report and review of the literature.

We believe this is the first Australian reported case of anal carcinoma complicating Crohn's disease. The opportunity has been taken to present a detailed case report and review the increasing overseas literature about this problem.