Recombinant leptin administration improves early angiogenesis in full-thickness skin flaps: an experimental study.

BACKGROUND: Leptin is a potent direct angiogenic factor that stimulates endothelial cell migration and activation in vitro, and angiogenesis in vivo. In addition, leptin seems to play an important role in angiogenesis as it promotes the formation of new blood vessels. OBJECTIVE: To determine the effect of local application of exogenous leptin on the survival of full thickness skin flaps in an experimental animal model. MATERIALS AND METHODS: Ninety Sprague-Dawley rats were used in this study. A full thickness dorsal flap (10 cm x 2 cm) with the pedicle located at the level of the iliac crest was designed. Animals were divided into ten groups of nine animals each. In the distal two thirds of the flap and by means of subdermal injection at 8 different locations, rats were injected with 100 ng/ml leptin, 250 ng/ml leptin, 500 ng/ml leptin, 1000 ng/ml leptin (groups A, B, C and D), 1 microg/ml VEGF (group E), or 1 ml saline (control group), respectively. For each of the four leptin doses used, another animal group was injected with a combination of leptin/antileptin: 100 ng/ml leptin with 150 ng/ml antileptin, 250 ng/ml leptin with 375 ng/ml antileptin, 500 ng/ml leptin with 750 ng/ml antileptin or 1000 ng/ml leptin with 1500 ng/ml antileptin (groups A1, B1, C1 and D1, respectively), in order to study the inhibition of the leptin factor. Nine rats served as controls and were injected with 1 ml saline solution. Rats were sacrificed 3, 7 and 9 days postoperatively. After sacrifice of the animals, the skin was grossly arranged on its appearance, colour and texture. Full thickness skin flaps were dissected for histological examination. A qualitative analysis of angiogenesis in the flap was conducted following a standard hematoxylin and eosin stain. The wound tissue samples from each experimental group underwent immunohistochemical evaluation of microvessel density by endothelial cell staining with mouse anti-rat CD 34 monoclonal antibody. RESULTS: Immunohistochemical staining revealed that more granulation tissue and improved angiogenesis were observed in group D (1000 ng/ml leptin) flaps compared to those in the VEGF, leptin/antileptin and saline groups. In addition, skin flap survival rate in group D (1000 ng/ml leptin) and group E (1 microg/ml VEGF) were significantly better than those of the other groups. The most impressive formation of new blood vessels was noted in the groups with the higher leptin doses. Surgical wounds in the control, as well as in the leptin/antileptin groups, did not demonstrate any new vessels. CONCLUSION: Exogenous administration of recombinant leptin increases early skin flap angiogenesis in an experimental animal model. Local application of leptin could efficiently improve survival of ischemic skin flaps.

Exogenously-administered leptin increases early incisional wound angiogenesis in an experimental animal model.

BACKGROUND: Leptin is a potent direct angiogenic factor that stimulates endothelial cell migration and activation in vitro, as well as angiogenesis in vivo. In addition, leptin seems to play an important role in clinical angiogenesis by promoting the development of new blood vessels. OBJECTIVE: To determine the effect of exogenously administered leptin on incisional wound healing in an experimental animal model. MATERIALS AND METHODS: Sixty-three Sprague-Dawley male mice were used for the study. Full thickness incisional wound was considered as the wound model. The mice were divided into seven groups of nine animals each. Surgical wounds were injected with murine recombinant leptin. Three different leptin doses of 100 pg/ml, 200 pg/ml and 500 pg/ml were used in different animal groups (A, B and C). For each of the three leptin doses used, another animal group was evaluated with a combined injection of leptin and antileptin: 100 pg/ml leptin with 50 pg antileptin, 200 pg/ml leptin with 100 pg antileptin, 500 pg/ml leptin with 250 pg antileptin (A1, B1, and C1), in order to study the inhibitory effect on the leptin factor. Nine mice served as controls. These were injected with 0.3 ml water for injection solution. Mice were sacrificed 3, 7 and 9 days postoperatively. After sacrifice of the animals, the skin was grossly assessed for appearance, colour and texture. Full thickness incisional wounds were dissected for histological examination. A qualitative analysis of angiogenesis in the surgical wound was conducted following a standard hematoxylin and eosin stain. The wound tissue samples from each experimental group underwent immunohistochemical evaluation of microvessel density by endothelial cell staining with mouse anti-rat CD34 monoclonal antibody. RESULTS: The most impressive growth of new blood vessels appeared seven and nine days after treatment with the highest leptin doses. There were no significant differences in microvessel density at seven or nine postoperative days among different groups treated with leptin. None of the wounds from the control group, or those from animal groups treated with the combined injection of leptin and antileptin developed any new vessels. CONCLUSION: Exogenous administration of leptin may increase early tissue angiogenesis in the incisional wound of an experimental animal model.

Aberrant E-cadherin and alpha-catenin expression in prostate cancer: correlation with patient survival.

E-cadherin maintains the normal differentiated phenotype in epithelial cells; this function is partly mediated by alpha-catenin, which links E-cadherin to the cell cytoskeleton. Dysfunction of E-cadherin in vitro and in vivo is associated with an invasive phenotype. However, the role of alpha-catenin is largely undetermined. We analyzed the expression of E-cadherin and alpha-catenin in prostate cancer to assess the relationship of abnormal expression to stage, grade and survival. E-cadherin expression was evaluated in 99 prostate cancers. In 79 of those specimens, alpha-catenin was also assessed. In benign prostatic epithelium, both E-cadherin and alpha-catenin were expressed uniformly at the cell membrane. Abnormal E-cadherin expression was found in 56% of cancer specimens, whereas alpha-catenin expression was abnormal in 42%. Abnormal expression of each molecule was significantly correlated with Gleason score (P < 0.0001) and the ratio of resection chippings infiltrated by tumor (P < 0.0001). E-cadherin expression was also associated with the extent of disease on the initial bone scan (P = 0.017). Univariate analysis showed significantly lower survival rate for patients with abnormal E-cadherin (P = 0.0003) or alpha-catenin expression (P = 0.031). Multivariate regression analysis showed that the prognostic value of E-cadherin was independent of tumor grade but not of metastasis. These results suggest that perturbation of cell-cell adhesion is involved in the progression of prostate cancer and that analysis of E-cadherin expression may be clinically useful.

Risk factors for conversion of laparoscopic cholecystectomy to open cholecystectomy.

BACKGROUND: Conversion to open cholecystectomy is still required in some patients. The aim of this study was to evaluate preoperative factors associated with conversion to open cholecystectomy in elective cholecystectomy and acute cholecystitis. METHODS: The records of 1,804 patients who underwent cholecystectomy from May 1992 to January 2004 were reviewed retrospectively. The demographics and preoperative data of patients who required conversion to laparotomy were compared to those with successful laparoscopic cholecystectomy. RESULTS: Conversion to open cholecystectomy was needed in 94 patients (5.2%),of which 44 (2.8%) had no inflammation and 50 (18.4%) had acute inflammation of the gallbladder. Male gender, age older than 60 years, previous upper abdominal surgery, diabetes, and severity of inflammation were all significantly correlated with an increased conversion rate to laparotomy. Also, the conversion from laparoscopic to open cholecystectomy in acute cholecystitis patients was associated with greater white blood cell count, fever, elevated total bilirubin, aspartate transaminase, and alanine transaminase levels, and the various types of inflammation. CONCLUSIONS: None of these risk factors were contraindications to laparoscopic cholecystectomy. This may help predict the difficulty of the procedure and permit the surgeon to better inform patients about the risk of conversion from laparoscopic to open cholecystectomy.

Delayed perforation of the large bowel due to thermal injury during laparoscopic cholecystectomy.

We report a case of delayed perforation of the large bowel because of thermal injury during a laparoscopic cholecystectomy. A 78-year-old male with symptomatic cholelithiasis underwent a difficult laparoscopic cholecystectomy because of multiple adhesions resulting from two previous cholecystitis episodes. The patient recovered well after surgery and was discharged on post-operative day 2. On postoperative day 10, the patient returned to the hospital with peritonitis. An exploratory laparotomy revealed perforation of the wall of the hepatic flexure of the large bowel, which was centred in a necrotic area 1 cm in diameter. The perforation was sutured and a temporary ileostomy performed, which was closed at a later date. The patient was doing well at a 10-month follow-up review. A delayed rupture of any part of the bowel after laparoscopic surgery can be potentially fatal if not treated during an emergency exploratory laparotomy, even if the clinical signs are not severe.

Serum levels of E-selectin, ICAM-1 and VCAM-1 in colorectal cancer patients: correlations with clinicopathological features, patient survival and tumour surgery.

The serum concentrations of the cell adhesion molecules E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were investigated in 63 patients with colorectal cancer and in 51 controls by an enzyme-linked immunosorbent assay (ELISA). Their relationship to clinicopathological variables and patient survival and changes in their levels after surgery were examined. Colorectal cancer patients showed significantly higher serum levels of E-selectin, ICAM-1 and VCAM-1 compared with healthy controls. There was a significant association between the serum levels of these molecules, disease stage and the presence of both lymph node and distant metastases. Both ICAM-1 and VCAM-1 levels correlated with serum E-selectin and carcinoembryonic antigen (CEA) levels. Serum levels of all three molecules decreased significantly after radical resection of the tumour. Elevated pre-operative E-selectin, ICAM-1 and VCAM-1 levels were significant prognostic factors, although not independent of stage, for patient survival. These findings suggest that serum concentrations of E-selectin, ICAM-1 and VCAM-1 may reflect tumour progression and metastasis. Since these markers are linked to CEA levels, it is uncertain whether their measurement will prove cost-effective in colorectal cancer management.

Umbilical port metastasis from gallbladder carcinoma after laparoscopic cholecystectomy.

A case of gallbladder carcinoma is presented where metastatic tumour developed at the abdominal wall port site following laparoscopic cholecystectomy.

Expression patterns of beta-catenin in in situ and invasive breast cancer.

BACKGROUND: beta-Catenin plays a central role in the E-cadherin/catenin cell-cell adhesion complex and is possibly involved in cellular signalling pathways. In this study, we evaluated the expression patterns of this molecule in in situ and invasive breast cancer. METHODS: The expression of beta-catenin was evaluated in 121 breast cancer specimens by immunohistochemistry. Its relationship to clinicopathological features was also investigated. RESULTS: Altered beta-catenin expression was found in 68% of tumours. Lobular carcinomas showed abnormal beta-catenin expression more frequently (77%) than ductal carcinomas (64%) with 46% of lobular cases showing complete absence of beta-catenin immunoreactivity. Cytoplasmic beta-catenin localization was seen only in ductal carcinomas. Aberrant beta-catenin expression was observed in 54% of ductal carcinomas in situ with highly concordant beta-catenin expression patterns in the nearby in situ and invasive components. CONCLUSIONS: Quantitative and qualitative changes in beta-catenin expression occur in a considerable proportion of in situ and invasive ductal carcinomas and are more prominent in invasive lobular carcinomas.

Immunohistochemical detection of oestrogen receptors in ductal carcinoma in situ of the breast.

The expression of oestrogen receptor (ER) protein in invasive carcinoma of the breast and its clinical significance has been extensively evaluated. Little information is available regarding ER expression in ductal carcinoma in situ (DCIS). In this study, 46 formalin-fixed, paraffin-embedded tissue specimens of mammographically detected DCIS were evaluated immunohistochemically for the presence of ER using specific monoclonal antibodies against ER (ER-ICA Abbott Lab). The associations between ER expression and histological type, degree of differentiation and patient menopausal status were evaluated. Positive ER staining was present in 72% of cases. Non-comedo types of DCIS were more frequently ER-positive than comedocarcinoma. ER-positive tumours were inversely correlated with the presence of nuclear pleomorphism. The incidence of ER in pre-menopausal and post-menopausal women was similar. In conclusion, ER expression is present in a considerable percentage of DCIS, and ER-positivity is associated with the degree of differentiation and non-comedo carcinoma variants.

Mucins as immunogenic targets in cancer.

Abnormal mucins are overexpressed by many malignant adenocarcinomas. The variation in their expression and glycosylation makes certain immunodominant peptide core epitopes available for immunological recognition. We reviewed the structural differences between "native" mucins and those detected on malignant cells, a knowledge of which would aid in the design of better anti-mucin vaccines for use in several carcinomas. We also considered the character of inducible anti-MUC1 immune responses reported from recent animal experiments as well as the role of MUC1-transgenic animal models in understanding mucin immunoreactivity. We concluded that the provocation of an anti-MUC1 immune response may be used for the development of a vaccine strategy, which holds promise for therapeutic antineoplastic interventions.

Expression patterns of alpha-, beta- and gamma-catenin in pancreatic cancer: correlation with E-cadherin expression, pathological features and prognosis.

BACKGROUND: The E-cadherin-catenin cell adhesion complex has been implicated in tumour invasion and metastasis. In this study, we evaluated the clinical significance of E-cadherin and catenin expression in pancreatic cancer. MATERIALS AND METHODS: The immunohistochemical expression and cellular co-localization of alpha-, beta- and gamma-catenin were investigated in 43 paraffin-embedded specimens of pancreatic cancer. The relationship between their expression and E-cadherin expression, clinicopathological features and prognosis was evaluated. RESULTS: Abnormal alpha-, beta- and gamma-catenin expression was found in 37%, 44% and 40% of cases, respectively. Both alpha-catenin and gamma-catenin expression correlated with disease stage and with lymph node and distant metastases, whereas aberrant beta-catenin expression only correlated with the presence of lymph node metastases. There was a significant and progressive concordance between E-cadherin and alpha-, beta- and gamma-catenin expression patterns, respectively. The expressions of alpha-, beta- and gamma-catenin also significantly correlated with one another. All three catenins, like E-cadherin, were associated with a poor prognosis, but only E-cadherin and alpha-catenin were independent prognostic factors for cancer-specific survival. CONCLUSION: Changes in catenin expression and pancreatic cancer progression are possibly related events. The expression of E-cadherin and alpha-catenin may add useful new prognostic information.

Prognostic significance of soluble adhesion molecules in Hodgkin's disease.

BACKGROUND: Cell adhesion may play a pivotal role in the development, progression and metastasis of solid malignancies. We evaluated the serum concentration of four adhesion molecules and their prognostic significance in patients with Hodgkin's Disease (HD). PATIENTS AND METHODS: Serum samples from 20 HD patients were collected at diagnosis, after 3 cycles of chemotherapy and at completion of treatment and compared with a control group of 29 apparently healthy subjects. Soluble forms of E-Selectin (sE-Selectin), ICAM-1 (sICAM-1), VCAM-1 (sVCAM-1) and E-Cadherin (sE-Cad) were measured by standard ELISA assays. RESULTS: Significantly increased serum levels of sICAM-1 and sE-Selectin were determined in HD patients at diagnosis compared to controls (p<0.0001), while sVCAM-1 at diagnosis correlated significantly with both sICAM-1 and sE-Selectin levels (r=0.5, p=0.03). Chemotherapy resulted in a significant decrease of sICAM-1 and sE-Selectin levels (p=0.02 and p=0.002, respectively). CONCLUSION: Serum levels of ICAM-1 and E-Selectin in newly diagnosed HD patients were found significantly increased, suggesting a possible involvement of these two molecules in the pathogenesis of the disease. Their rapid decrease following chemotherapy was found to be an independent predictor of response to treatment.

Circulating soluble E-cadherin levels are of prognostic significance in patients with multiple myeloma.

BACKGROUND: The epithelial transmembrane molecule E-cadherin (E-Cad) is the prime mediator of epithelial cell-cell adhesion, through homotypic interactions. It also participates in the maintenance of cytoskeletal structure and cell-cell signalling, while there are no published reports of expression of E-Cad in non-epithelial tissues. We examined whether the circulating levels of soluble E-Cad in newly diagnosed patients with multiple myeloma (MM) are of prognostic significance. PATIENTS AND METHODS: We used an ELISA method to determine the levels of circulating soluble E-cadherin (sE-Cad) in 21 newly diagnosed patients with MM and in 29 healthy volunteers, as a control group. RESULTS: MM patients demonstrated increased circulating levels of sE-Cad, compared with controls (p<0.0001). Increased circulating sE-Cad levels correlated with LDH levels at diagnosis (p<0.001) and poor prognosis. Multivariate analysis demonstrated that sE-Cad levels are an independent prognostic factor of survival (p<0.0207). CONCLUSION: Our data suggest that adhesion molecules play a role in the pathogenesis of MM, establish sE-Cad as an independent marker of survival and, finally, provide evidence of non-epithelial production of E-Cad in MM patients.

Expression patterns of the novel catenin p120cas in gastrointestinal cancers.

p120cas is involved in signal transduction upon src or growth factor stimulation as well as in E-cadherin mediated cell adhesion and may play an important role in carcinogenesis. In this study, we evaluated immunohistochemically the expression and cellular localization of p120cas in 40 gastric, 43 colorectal and 20 pancreatic carcinomas, and examined the relationship between p120cas expression and pathological features. Altered p120cas expression was observed in 70%, 65% and 60% of gastric, colorectal and pancreatic cancers, respectively. The most common abnormality was of cytoplasmic expression associated with loss of membranous distribution found in 37% of gastric, in 25% of colorectal and in 25% of pancreatic cancers. Heterogeneous staining was noted in 15%, 19% and 20%, and complete loss of expression in 18%, 21% and 15% of gastric, colorectal and pancreatic cancers, respectively. There was no correlation between p120cas staining pattern and tumour grade or stage. Aberrant expression of p120cas which may reflect changes in signal transduction pathways occurs frequently in human malignancies.

Serum levels of tumor necrosis factor-alpha and nutritional status in pancreatic cancer patients.

BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is a multifunctional cytokine associated with cancer-related cachexia. In this study we evaluated serum levels of TNF-alpha in pancreatic cancer patients and investigated their relationships to cachexia. PATIENTS AND METHODS: Serum TNF-alpha levels were determined in 63 patients with pancreatic cancer using an enzyme immunoassay specific for human TNF-alpha. RESULTS: Serum TNF-alpha levels were detected in 36.5% of patients. Patients with metastatic disease showed significantly higher positive serum TNF-alpha rate compared to those with non-metastatic disease. Patients with detectable serum TNF-alpha levels had significantly lower body weight and body mass index, lower haematocrit and haemoglobin values, and lower serum total protein and albumin levels compared to those with undetectable TNF-alpha levels. Serum TNF-alpha levels were inversely correlated with body weight, body mass index, haematocrit, haemoglobin, and serum protein and albumin levels. CONCLUSIONS: TNF-alpha levels are detectable in the serum of pancreatic cancer patients, particularly in those with advanced disease, and these levels correlate with poor nutritional status.

Aberrant E-cadherin expression associated with loss of differentiation and advanced stage in human pancreatic cancer.

E-cadherin is a cell-cell adhesion molecule involved in tumour invasion and metastasis. We evaluated E-cadherin expression immunohistochemically in 43 formalin-fixed, paraffin-embedded specimens of pancreatic cancer and investigated its relationship to histopathological features. In non-cancerous pancreatic cells E-cadherin immunoreactivity was localized at the cell membrane, particularly at the intercellular junctions. Abnormal E-cadherin expression was found in 18 (42%) cases. A significantly higher proportion of poorly-differentiated tumours (71%) showed abnormal E-cadherin expression compared with moderately (50%) and well (19%) differentiated tumours (P = 0.037). There was a significant correlation between abnormal E-cadherin expression and lymph node involvement (P = 0.013), the presence of distant metastases (P = 0.034) and advanced tumour stage (P = 0.025). These findings suggest that loss of normal E-cadherin expression is involved in the progression of pancreatic cancer.

An unusual cause of delayed presentation of laparoscopic common bile duct injury.

We describe an unusual case of a laparoscopic common bile duct (CBD) injury that presented with cholangitis 2 years after an apparently uneventful laparoscopic cholecystectomy. Preoperative ultrasound and endoscopic retrograde cholangiography suggested choledocholithiasis, showing proximal and intrahepatic duct dilatation with an inability to relieve the obstruction. At surgery, a lateral injury of the CBD wall with partial wall loss was found, adherent to an amorphous pigmented mass with the appearance of a knitted fabric causing CBD obstruction. The CBD was successfully reconstructed with a Roux-en-Y end-to-side hepaticojejunostomy, where the end of the Roux loop was anastomosed to the lateral CBD defect.

Laparoscopic cholecystectomy in a patient with previous open cholecystostomy.

We report the case of a successful elective interval laparoscopic cholecystectomy in a patient with a previous tube cholecystostomy that had been performed surgically 8 weeks earlier for an attack of acute calculous cholecystitis. At surgery, the major omentum was adherent to the right lateral abdominal wall, completely covering the liver edge, the gallbladder, and the inserted tube. The gallbladder and the tube within it were dissected free from the abdominal wall and the greater omentum, the cholecystostomy tube was removed, and the operation was completed successfully without any further difficulties.

Laparoscopic cholecystectomy in patients with previous upper or lower abdominal surgery.

BACKGROUND: Previous abdominal surgery has been reported as a relative contraindication to laparoscopic cholecystectomy. This study specifically examined the effect of previous intraabdominal surgery on the feasibility and safety of laparoscopic cholecystectomy. METHODS: Data from 1,638 consecutive patients who underwent laparoscopic cholecystectomy were reviewed and analyzed for open conversion rates, operative times, intra- and postoperative complications, and hospital stay. RESULTS: Of the 1,638 study patients 473 (28.9%) had undergone previous abdominal surgery: 58 upper and 415 lower abdominal operations. The 262 patients who had undergone only a previous appendectomy were excluded from further analysis. Adhesions were found in 70.7%, 58.8% and 2.1% of patients respectively, who had previous upper, lower or no previous abdominal surgery with adhesiolysis required, respectively, in 78%, 30% and 0% of these cases. There were no complications directly attributable to adhesiolysis. Patients with previous upper abdominal surgery had a longer operating time (66.4 +/- 34.2 min), a higher open conversion rate (19%), a higher incidence of postoperative wound infection (5.2%), and a longer postoperative stay (3.4 +/- 2.1 days) than those who had undergone previous lower abdominal surgery (50.8 +/- 24 min, 3.3%, 0.7%, and 2.6 +/- 1.4 days, respectively) and those without prior abdominal surgery (47.4 +/- 25.6 min, 5.4%, 1.2%, and 2.8 +/- 1.9 days, respectively). CONCLUSIONS: Previous abdominal operations, even in the upper abdomen, are not a contraindication to safe laparoscopic cholecystectomy. However, previous upper abdominal surgery is associated with an increased need for adhesiolysis, a higher open conversion rate, a prolonged operating time, an increased incidence of postoperative wound infection, and a longer postoperative stay.

Serum E-cadherin concentrations and their response during laparoscopic and open cholecystectomy.

BACKGROUND: Elevated serum levels of the cell adhesion molecule E-cadherin have been associated with the presence of tissue injury and inflammation. We compared soluble E-cadherin response during laparoscopic and open cholecystectomy. METHODS: The E-cadherin response to surgery was studied in 16 patients undergoing laparoscopic cholecystectomy and 12 patients undergoing open cholecystectomy. Serum E-cadherin levels were measured by an enzyme immunoassay (ELISA) preoperatively, 10 and 30 min after the commencement of surgery, and at 6 and 24 h following the operation. RESULTS: Serum E-cadherin levels decreased progressively during laparoscopic cholecystectomy; their concentrations at 24 h after surgery were significantly lower when compared with preoperative values. In the open cholecystectomy group, serum E-cadherin levels did not differ from preoperative values at any time point. Serum E-cadherin concentrations at 24 h after surgery and the cumulative E-cadherin response were significantly higher in the open cholecystectomy group than in the laparoscopic group. CONCLUSION: Compared with open cholecystectomy, the cumulative E-cadherin response is significantly reduced following laparoscopic cholecystectomy.