RESUMEN
Pancreatic adenocarcinoma is among the most aggressively invasive malignancies. The immunoglobulin superfamily member carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is emerging as an important determinant of the malignant phenotype in a range of cancers. We sought to define the role of CEACAM6 in pancreatic adenocarcinoma cellular invasiveness. CEACAM6 was stably overexpressed in Capan2 cells, which inherently express low levels of CEACAM6. Retrovirally mediated RNA interference was used to silence CEACAM6 expression in BxPC3 cells, which inherently overexpress CEACAM6. Cellular invasiveness was quantified using a modified Boyden chamber assay. Overexpression of CEACAM6 increased Capan2 cellular invasiveness, whereas CEACAM6 knockdown attenuated BxPC3 invasiveness. A role for the c-Src tyrosine kinase in mediating CEACAM6-dependent invasiveness was defined using constitutively active and dominant-negative c-Src expression constructs. c-Src-dependent modulation of matrix metalloproteinase-9 activity contributes significantly to the increased cellular invasiveness induced by CEACAM6 overexpression. Levels of CEACAM6 expression can modulate pancreatic adenocarcinoma cellular invasiveness in a c-Src-dependent manner. This pathway warrants further investigation as a target for therapy.
Asunto(s)
Adenocarcinoma/genética , Adenocarcinoma/patología , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/farmacología , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/farmacología , Perfilación de la Expresión Génica , Invasividad Neoplásica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Animales , Antígenos CD , Western Blotting , Proteínas Ligadas a GPI , Genes src , Humanos , Ratones , Ratones Desnudos , Interferencia de ARN , Trasplante Heterólogo , Células Tumorales CultivadasRESUMEN
BACKGROUND: Inadequate or inappropriate cell-substrate contact triggers a subset of apoptotic cell death, termed anoikis. Resistance to anoikis is a characteristic of malignant cells that is associated with increased tumorigenesis and metastasis. Focal adhesion kinase (FAK) is an important regulator of cell survival and migration and cell cycle progression. We tested the hypothesis that FAK gene silencing would promote anoikis and reverse acquired anoikis resistance in human pancreatic adenocarcinoma cells. METHODS: FAK expression was assessed by Northern and Western blot analysis. Anoikis was induced in PANC1, BxPC3, MiaPaCa2, and Mia(AR) (an anoikis-resistant derivative of MiaPaCa2) with the use of polyHEMA culture. FAK expression was suppressed by RNA interference. Anoikis was detected by YO-PRO-1/propidium iodide staining and flow cytometry. Fluorometric caspase profiling was performed. Metastasis was assayed in a nude mouse orthotopic xenograft model. RESULTS: The cell lines that were tested showed marked variation in their anoikis resistance, greater resistance being associated with higher levels of FAK expression. FAK gene silencing promoted anoikis in all cell lines and reversed acquired anoikis resistance in Mia(AR), which was associated with increased caspase activation. Suppression of FAK expression also inhibited metastasis in the nude mouse model. CONCLUSION: FAK gene silencing suppresses anoikis resistance in pancreatic adenocarcinoma cells. FAK represents a potential target for novel antimetastatic therapies.
Asunto(s)
Adenocarcinoma/fisiopatología , Adenocarcinoma/secundario , Anoicis , Silenciador del Gen , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/fisiopatología , Proteínas Tirosina Quinasas/genética , Adenocarcinoma/genética , Adenocarcinoma/patología , Animales , Caspasas/metabolismo , Línea Celular , Quinasa 1 de Adhesión Focal , Proteína-Tirosina Quinasas de Adhesión Focal , Humanos , Ratones , Ratones Desnudos , Neoplasias Pancreáticas/metabolismo , Proteínas Tirosina Quinasas/metabolismoRESUMEN
BACKGROUND: Pilonidal disease is a common debilitating condition. This prospective randomised study compared excision of pilonidal disease with a scalpel or diathermy with respect to operation time, postoperative pain, functional recovery and wound healing. PATIENTS AND METHODS: Patients undergoing surgery for pilonidal disease were randomised to excision by scalpel (group 1) or diathermy (group 2). Patients received regular peri-operative oral analgesia and a standardised general anaesthetic technique. Duration of operation was recorded. Following surgery, pain, analgesic requirements, sedation, nausea and vomiting scores and time to mobilise and time to complete healing were compared. RESULTS: Statistical significance between groups was obtained for five outcomes after 32 patients had been recruited; of these, 81% were admitted as emergencies with an abscess. The duration of surgery in group 2 was significantly less, postoperative pain scores and morphine requirements were lower and mobility was regained sooner. CONCLUSIONS: We advocate the use of diathermy needle rather than scalpel blade when undertaking excision of pilonidal disease in both acute and chronic patients.
Asunto(s)
Diatermia/métodos , Seno Pilonidal/terapia , Adolescente , Adulto , Femenino , Humanos , Tiempo de Internación , Masculino , Dolor Postoperatorio/etiología , Seno Pilonidal/cirugía , Instrumentos Quirúrgicos , Resultado del Tratamiento , Cicatrización de Heridas/fisiologíaRESUMEN
AIMS: The Royal College of Surgeons of England and the Association of Coloproctology of Great Britain and Ireland guidelines for the management of colorectal cancer were published in 1996. We audited our practice against these guidelines. METHODS: Data from 211 consecutive patients undergoing colorectal cancer surgery, between September 1999 and September 2000, have been prospectively collected. Preoperative large bowel and liver imaging, assessment by colorectal specialist nurses and median number of lymph nodes resected have been compared between specialist colorectal and non-colorectal surgeons for rectal and colonic cancers. The adequacy of resection and rates of abdomino-perineal resection have been compared for rectal cancers. Following presentation of our findings, we re-audited practice between January and June 2002. RESULTS: There was marked variation in practice within our hospital. Colorectal specialists were more likely to conform to best practice guidelines, performed fewer abdomino-perineal resections and tended to perform more extensive lymphadenectomy. Following presentation of these data, compliance with guidelines was markedly improved and the number of rectal procedures performed by non-colorectal surgeons decreased. CONCLUSIONS: The ability of audit to change practice has been demonstrated. We feel that completion of this audit cycle has improved the quality of service we provide for colorectal cancer patients in our hospital.