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Accumulating evidence indicates that the human papillomavirus (HPV) E6 protein plays a crucial role in the development of cervical cancer. Subpopulations of cells that reside within tumours are responsible for tumour resistance to cancer therapy and recurrence. However, the identity of such cells residing in cervical cancer and their relationship with the HPV-E6 protein have not been identified. Here, we isolated sphere-forming cells, which showed self-renewal ability, from primary cervical tumours. Gene expression profiling revealed that cluster of differentiation (CD) 55 was upregulated in primary cervical cancer sphere cells. Flow-cytometric analysis detected abundant CD55(+) populations among a panel of HPV-positive cervical cancer cell lines, whereas few CD55(+) cells were found in HPV-negative cervical cancer and normal cervical epithelial cell lines. The CD55(+) subpopulation isolated from the C33A cell line showed significant sphere-forming ability and enhanced tumourigenicity, cell migration, and radioresistance. In contrast, the suppression of CD55 in HPV-positive CaSki cells inhibited tumourigenicity both in vitro and in vivo, and sensitized cells to radiation treatment. In addition, ectopic expression of the HPV-E6 protein in HPV-negative cervical cancer cells dramatically enriched the CD55(+) subpopulation. CRISPR/Cas9 knockout of CD55 in an HPV-E6-overexpressing stable clone abolished the tumourigenic effects of the HPV-E6 protein. Taken together, our data suggest that HPV-E6 protein expression enriches the CD55(+) population, which contributes to tumourigenicity and radioresistance in cervical cancer cells. Targeting CD55 via CRISPR/Cas9 may represent a novel avenue for developing new strategies and effective therapies for the treatment of cervical cancer. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Introduction Peritoneal metastases (PM) can be treated with cytoreduction surgery (CRS) with intraoperative heated intraperitoneal chemotherapy (HIPEC) plus or minus early postoperative intraperitoneal chemotherapy (EPIC). HIPEC + EPIC may be associated with more complications than HIPEC alone. Methods A prospective database of consecutive patients undergoing CRS + HIPEC ± EPIC at the University of Calgary between February 2000 and May 2011 was reviewed. Patient, tumor, and perioperative variables included peritoneal cancer index (PCI), completeness of cytoreduction (CCR) score, HIPEC ± EPIC type, and grade III/IV complications. Results 198 patients had a CCR score of 0/1 and received: (1) HIPEC mitomycin C + EPIC 5-fluorouracil for 5 days (n = 85; February 2000–January 2008); or (2) HIPEC oxaliplatin with IV 5-fluorouracil + no EPIC (n = 113; February 2008–May 2011). Clinicodemographics were similar except PCI was higher in the HIPEC-alone group (mean PCI 22 vs. 17; P = 0.02). The rate of grade III/IV complications was higher in the HIPEC + EPIC group (44.7% vs. 31.0%; P = 0.05). On multivariate logistic regression only HIPEC + EPIC and PCI > 26 were associated with an increased rate of complications. Conclusion In patients with PM, the use of EPIC, in combination with CRS and HIPEC, is associated with an increased rate of complications. Surgeons should consider using HIPEC only (without EPIC). J. Surg. Oncol. 2013;107:591–596. © 2012 Wiley Periodicals, Inc.

Background: Deleted in liver cancer 2 (DLC2) gene, a putative tumour suppressor gene, encodes a Rho GTPase-activating protein (RhoGAP) with GAP activity specific for RhoA. It exhibits tumour suppressor functions and inhibits tumour cell proliferation, migration as well as transformation. Aims: In this study, we aimed to investigate the underlying mechanisms of the DLC2 gene in suppressing cell migration and cell growth. HepG2 hepatoma cells were stably transfected with the DLC2g isoform, which contains the RhoGAP domain. Methods and results: On performing immunofluorescence staining and Western blot analysis, the expression of the focal adhesion protein paxillin was found to be much reduced in DLC2g-stable clones. Upon flow cytometric analysis of the cell cycle profiles, the DLC2gstable clones were shown to have a higher population of cells arrested at the G1 phase than the EGFP vector-stable clone, suggesting that downregulation of RhoA activity in DLC2g-stable clones inhibited cell cycle progression. In the DLC2g-stable clone, the levels of Raf-1 and extracellular signal-regulated kinase (ERK) 1/2 were decreased as compared with those of the parental HepG2, EGFP vector and DLC2g‐GAP defective mutant-stable clones. Furthermore, the ribosomal kinase p70S6K, a downstream target of ERK1/2, was suppressed in the DLC2-stable clones. On the contrary, when DLC2 was knocked down by siRNA in HepG2 cells, the expression levels of phosphop70S6K and phospho-ERK1/2 were upregulated. Conclusion: Our data show that DLC2 inhibits the activity of Raf-1‐ERK1/2‐p70S6K via its RhoGAP function, resulting in the suppression of cell growth. Further studies on the molecular signalling between DLC2 and p70S6K may provide an insight into its growth suppressor function.

Purpose: The management of lacrimal canalicular injury is controversial. It is believed that practice varies widely among surgeons. Methods: One hundred and twenty National Health Service-based Consultant Ophthalmologists with oculoplastic interest across the United Kingdom (UK) were identified via the website http://www.specialistinfo.com, which is a website that asks UK consultants to identify their areas of subspecialty interests. Questionnaires were sent out to them to determine caseload, intraoperative techniques (magnification, suture and stents) and postoperative management (antibiotic use, stent placement and replacement and secondary lacrimal surgery) of patients with canalicular injuries. Results: Eighty-nine (74%) completed questionnaires were returned and analysed. Most (63%) of the respondents treated between one and five canalicular injuries over the past year. Thirty-eight (43%) of them would repair a monocanalicular injury only if the lower canaliculus was involved and 36 (40%) respondents would always repair a monocanalicular injury. Eighty-two (92%) respondents used magnification during surgery. Fifty-one (57%) respondents would never consider using the pigtail probe. Eighty-five (96%) would use the bubble test and/or fluorescein dye to locate the severed medial canalicular end. Vicryl or dexon was the suture of choice for 76 (85%) and 63 (71%) respondents for repairing pericanalicular and canalicular tissues, respectively. Thirteen (14.6%) respondents did not stent their canalicular repairs. Forty-seven (53%) routinely used prophylactic antibiotics. Sixty-eight (76%) respondents would wait between 3 and 12 months before undertaking further lacrimal surgery. Conclusion: This study confirmed that management of lacrimal canalicular injury varies widely among surgeons in the UK.