Impact by pancreatic stellate cells on epithelial-mesenchymal transition and pancreatic cancer cell invasion:adding a third dimension in vitro

Pancreatic cancer is associated with a highly abundant stroma and low-grade inflammation. In the local tumour microenvironment, elevated glucose levels, the presence of tumour-associated stellate cells and macrophages are hypothesised to promote the tumour progression and invasion. The present study investigated the influence by the microenvironment on pancreatic cancer cell invasion in vitro. After co-culture with tumour-associated pancreatic stellate cells (TPSCs), pancreatic cancer cells displayed up to 8-fold reduction in levels of epithelial-mesenchymal transition (EMT) markers E-cadherin and ZO-1, while β-catenin and vimentin levels were increased. A 3D organotypic model showed that TPSCs stimulated pancreatic cancer cell invasion, both as single cell (PANC-1) and cohort (MIAPaCa-2) invasion. The combined presence of TPSCs and M2-like macrophages induced invasion of the non-invasive BxPC-3 cells. High glucose conditions further enhanced changes in EMT markers as well as the cancer cell invasion. In summary, co-culture with TPSCs induced molecular changes associated with EMT in pancreatic cancer cells, regardless of differentiation status, and the organotypic model demonstrated the influence of microenvironmental factors, such as glucose, stellate cells and macrophages, on pancreatic cancer cell invasion

Metformin-mediated growth inhibition involves suppression of the IGF-I receptor signalling pathway in human pancreatic cancer cells.

Epidemiological studies have shown direct associations between type 2 diabetes and obesity, both conditions associated with hyperglycaemia and hyperinsulinemia, and the risk of pancreatic cancer. Up to 80% of pancreatic cancer patients present with either new-onset type 2 diabetes or impaired glucose tolerance at the time of diagnosis. Recent population studies indicate that the incidence of pancreatic cancer is reduced among diabetics taking metformin. In this study, the effects of exposure of pancreatic cancer cells to high glucose levels on their growth and response to metformin were investigated

Cationic polypeptides in a concept of oppositely charged polypeptides as prevention of postsurgical intraabdominal adhesions

Two differently charged polypeptides, α-poly-L-lysine and poly-L-glutamate, have previ- ously been shown to effectively reduce postoperative intraabdominal adhesions. Though α-poly-L-lysine showed toxicity in doses too close to the lowest the-rapeutic dose, the aim in the present study was to investigate the possible antiadhesive effect of another four cationic polypeptides

The prognostic role of cancer stem cell markers for long-term outcome after resection of colonic liver metastases

Background/Aim: To assess the expression of cancer stem cell (CSC) markers CD44, CD133 and CD24 in colon cancer liver metastases and analyse their predictive value for overall survival (OS) and disease-free survival (DFS) after liver resection. Materials and Methods: Patients operated on for colon cancer liver metastases were included. CSC marker expression was determined through immunohistochemistry analysis. OS and DFS were compared between marker-positive and marker-negative patients. Multivariate analysis was performed to select predictive variables for OS and DFS. Results: CD133-positive patients had a worse DFS than CD133-negative patients, with a median DFS of 12 and 25 months (p=0.051). Multivariate analysis selected CD133 expression as a significant predictor for DFS. CD44 and CD24 were not found to predict OS or DFS. Conclusion: CD133 expression in colonic liver metastases is a negative prognostic factor for DFS after liver resection. In the future, CD133 could be used as a biomarker for risk stratification, and possibly for developing novel targeted therapy

The role of SPARC expression in pancreatic cancer progression and patient survival.

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein that has been implicated in tumor-stroma interactions in pancreatic cancer. Here we evaluated the expression of SPARC during the progression of pancreatic cancer and its correlation with survival following curative intent surgery

Expression of peritumoral SPARC during distal cholangiocarcinoma progression and correlation with outcome

Objectives: Distal cholangiocarcinoma (dCCA) is a malignancy with a dismal prognosis. One of the hallmarks is the presence of a rich desmoplastic stroma believed to contribute to tumor progression and treatment resistance. Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycoprotein implicated in tumor-stroma interaction with prognostic correlation across several malignancies. The aim of the present study was to evaluate the expression pattern and prognostic significance of SPARC in resected dCCA and paired lymph node metastasis. Materials and methods: SPARC expression was evaluated in 59 resected dCCA samples and 25 paired lymph node metastases as well as 10 benign bile duct samples using immunohistochemistry. Stromal SPARC expression was scored semi quantitatively. Survival was estimated using the Kaplan–Meier method with associated log-rank test. Results: SPARC expression was absent in normal bile ducts. In dCCA, peritumoral stromal SPARC was detectable in 47/59 (80%) of samples with 40/59 (68%) classified as high stromal SPARC expression. There was a significantly lower proportion of SPARC positive stroma in paired lymph node metastasis 17/25 (68%) than the corresponding primary tumors 24/25 (96%) (p =.016). Stromal SPARC expression was associated with the presence of lymph node metastasis; high SPARC expression 31/40 (78%) versus low SPARC expression 9/19 (47%) (p =.013). In the present material there was no significant association between stromal SPARC expression and survival. Conclusions: Stromal SPARC expression occurs frequently in dCCA. Although significantly lower than in primary tumors stromal SPARC is frequently retained in paired lymph node metastasis suggesting a possible role in the metastatic process of dCCA

Expression of fibroblast activation protein and the clinicopathological relevance in distal cholangiocarcinoma

Objectives: The current survival of patients with distal cholangiocarcinoma (dCCA) is poor. There is a need to develop new prognostic and predictive biomarkers to improve the survival of patients. Fibroblast activation protein (FAP) expression has been associated with survival in several solid malignancies. The goal of this study was to evaluate the expression pattern and prognostic significance of FAP in dCCA. Materials and methods: FAP expression was examined in 57 resected dCCA specimens and 28 paired lymph node metastasis specimens, as well as 10 benign bile ducts using immunohistochemistry. FAP expression was scored in the epithelial and stromal component of the dCCA specimens. The association between FAP expression and prognosis was evaluated using univariable and multivariable statistical modeling. Results: FAP expression was absent in the benign controls. FAP expression was evident in the epithelial 43 (75%) and stromal compartment 34 (60%) of dCCA. There was no association between epithelial or stromal FAP expression and clinicopathological factors. Epithelial FAP expression (HR 0.4 95% CI 0.20–0.78; p=.007) but not stromal FAP expression was significantly associated with better survival in univariable and multivariable analysis. Conclusions: FAP overexpression is evident in dCCA. There was a positive association between epithelial FAP expression and better survival which merits further evaluation

Stromal fibronectin expression in patients with resected pancreatic ductal adenocarcinoma

Background: Pancreatic ductal adenocarcinoma (PDAC) is characterized by an extremely dense stroma, which has a fundamental role in tumor progression. Fibronectin (FN1) is the main constituent of the tumor stroma in pancreatic cancer. This study aimed to explore the association between FN1 and clinicopathological characteristics and disease survival. Methods: Formalin-fixed paraffin-embedded tissue samples from 138 patients with PDAC were constructed into a tissue microarray, followed by immunohistochemical analysis with a recombinant monoclonal FN1 antibody. Chi-square test or Fisher's exact test were used for comparison of FN1 expression and relevant clinicopathological parameters. Kaplan-Meier survival curves and Cox regression analyses were used to assess the association between FN1 and survival. Results: FN1 was detected in the stromal compartment in most cases (117/138, 84.8%). Compared to the low FN1 expression group, the high FN1 expression group had significantly larger tumor size (P = 0.002), more advanced T stage (P = 0.039) and N stage (P = 0.009), and also worse AJCC stage (P = 0.003). However, stromal FN1 expression was not associated with disease-free survival or overall survival. Conclusions: This study suggests that high stromal FN1 expression is associated with aggressive tumor characteristics in patients with resected PDAC. However, no association between FN1 expression and survival was found

Galectin 4 is a biomarker for early recurrence and death after surgical resection for pancreatic ductal adenocarcinoma

Background: Galectins are a group of carbohydrate-binding proteins that are involved in neoplastic development and progression. In a previous mass spectrometry-based study, we identified galectin 4 as a down-regulated protein in short-term survivors of pancreatic cancer. This study was performed to validate the prognostic value of galectin 4 in a larger cohort of pancreatic cancer patients undergoing surgical resection. Methods: Galectin 4 expression was evaluated by tissue microarrays and immunohistochemistry in 140 patients with surgically resected pancreatic cancer. Kaplan-Meier and Cox proportional hazards modeling were used to explore the association between galectin 4 and survival. Results: Galectin 4 staining expression was positive in 111 cases (79.3%). The expression of galectin 4 was significantly associated with tumor size (p =.008) and differentiation (p =.001). Galectin 4 expression was significantly correlated with disease recurrence within 1 year of surgery (adjusted HR 0.485, p =.027). There was also a significant association between galectin 4 and overall survival at 1 year (adjusted HR 0.482, p =.047) and at 3 years (adjusted HR 0.550, p =.025). Conclusion: Galectin 4 expression is a novel biomarker for early recurrence and mortality after surgical resection for pancreatic cancer

Low P4HA2 and high PRTN3 expression predicts poor survival in patients with pancreatic cancer

Background: The tumor microenvironment in pancreatic cancer has a multifaceted role in disease development and progression. Prolyl 4-hydroxylase subunit alpha 2 (P4HA2) and proteinase 3 (PRTN3) are involved in the synthesis and degradation of collagen in the tumor microenvironment and have been identified as prognostic biomarker candidates for pancreatic cancer in our previous mass spectro-metric study. This study aimed at validating prognostic performance of P4HA2 and PRTN3 in a larger cohort of patients. Methods: The expression of P4HA2 and PRTN3 was evaluated with tissue microarrays and immunohis-tochemistry in 140 patients with pancreatic cancer who underwent surgical resection. Kaplan–Meier and Cox proportional hazards regression modeling were used to explore the association of P4HA2 and PRTN3, either separately or combined, with clinicopathological factors and survival. Results: Most tumors were positive for P4HA2 (133/140, 95%), whereas 77 tumors (55%) were positive for PRTN3. Expression levels of P4HA2 and PRTN3 did not separately correlate with disease-free or overall survival, in either uni-or multivariable analysis. However, a low P4HA2 and high PRTN3 expression correlated with shorter disease-free survival (median 7.0 vs. 13.4 months, adjusted HR 3.24, 95% CI: 1.13–9.25, p ¼.028) and overall survival (median 8.5 vs. 25.8 months, adjusted HR 8.14, 95% CI: 3.41–19.44, p <.001). Conclusion: Our data show that a low P4HA2 and high PRTN3 expression correlates with poor survival in patients with pancreatic cancer, indicating the involvement of collagen deposition in the restraint of the tumor. The tumoral expression of PRTN3 reinforces the therapeutic potential of PR1-targeting immunotherapy in pancreatic cancer