Inhibition of IL-6 signaling significantly reduces primary tumor growth and recurrencies in orthotopic xenograft models of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal human tumors, with radical surgical resection as the only curative treatment option. However, resection is only possible in a small fraction of patients, and about 80% of the patients develop recurrencies. PDAC development is facilitated by the cytokine interleukin-6 (IL-6), which acts via classic and trans-signaling. Both pathways are inhibited by the anti-IL-6-receptor antibody tocilizumab, whereas the fusion protein sgp130Fc specifically blocks trans-signaling. Here, we show that conservative or adjuvant therapy with both inhibitors reduces tumor growth in an orthotopic model of human Colo357 cells in SCID/bg mice. In the conservative setting, median primary tumor weight was reduced 2.4-fold for tocilizumab and 4.4-fold for sgp130Fc. sgp130Fc additionally led to a decrease in microvessel density, which was not observed with tocilizumab. In the adjuvant therapeutic setting after surgical resection of the primary tumor, treatment with tocilizumab or sgp130Fc decreased the local recurrence rate from 87.5% in the control group to 62.5 or 50%, respectively. Furthermore, the median weight of the local recurrent tumors was clearly diminished, and both inhibitors reduced the number of distant metastases. A significant reduction of tumor weight and metastases-comparable to gemcitabine treatment-was also observed with both inhibitors in another model using the poorly differentiated PancTuI cells. Our findings demonstrate the inhibition of IL-6 as a new treatment option in PDAC.

Interleukin-6: a villain in the drama of pancreatic cancer development and progression.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a devastating malignancy with a poor prognosis and little treatment options. The development and progression of the disease is fostered by inflammatory cells and cytokines. One of these cytokines is interleukin-6 (IL-6), which plays an important role in a wide range of biologic activities. DATA SOURCES: A systematic search of PubMed was performed to identify relevant studies using key words such as interleukin-6, inflammatory cytokines, inflammation and pancreatic cancer or PDAC. Articles related to IL-6 and pancreatic cancer were systematically reviewed. RESULTS: IL-6 is elevated in the serum of pancreatic cancer patients and correlates with cachexia, advanced tumor stage and poor survival. Its expression is enhanced by hypoxia and proteins involved in pancreatic cancer development like Kras, mesothelin or ZIP4. IL-6 in turn contributes to the generation of a pro-tumorigenic microenvironment and is probably involved in angiogenesis and metastasis. In experimental mouse models of PDAC, IL-6 was important for the development and progression of precursor lesions. CONCLUSION: IL-6 emerges as a key player in pancreatic cancer development and progression, and hence should be considered as a new therapeutic target.

Preoperative risk evaluation of postoperative morbidity in IBD patients--impact of the POSSUM score.

BACKGROUND: The aim of this study was to assess the morbidity and mortality of patients undergoing surgery for inflammatory bowel disease (IBD) with special focus of the predictive value of the Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (POSSUM) scoring system for preoperative risk adjustment of postoperative morbidity. METHODS: The operative notes and hospital files of 191 patients with IBD were analyzed. The POSSUM scoring system was used to predict morbidity rates after surgery. The physiological sub-score of the POSSUM score was analyzed with regard to its ability to predict postoperative complications. RESULTS: The overall complication rate was 27.7%, and the mortality was 0.5%. The morbidity rate predicted by POSSUM was 28.4% and the mortality rate 7.2%. The mean POSSUM-phys sub-score in patients without the major complications (anastomotic leakages, peritonitis, bleeding) was significant lower compared to patients with at least one of these complications (14.7 vs. 18.6; p < 0.001). Regarding the major complications separately, there were significant differences in the POSSUM-phys scores in patients developing a sepsis (14.1 vs. 23.4; p < 0.001) and/or a peritonitis (14.8 vs. 19.2; p = 0.05), whereas patients developing an anastomotic leakage/suture dehiscence or a postoperative bleeding did not differ significantly. CONCLUSION: POSSUM was an accurate predictor of morbidity in IBD patients and overpredicted mortality. The POSSUM-phys score is a promising instrument for identifying patients at increased risk of developing major postoperative complications after surgery for IBD.

Imatinib mesylate inhibits proliferation and modulates cytokine expression of human cancer-associated stromal fibroblasts from colorectal metastases.

Recent data have expanded the concept that cancer-associated stromal fibroblasts (CAFs) play an important role in tumor invasion and angiogenesis. Here, we show that platelet-derived growth factor (PDGF) is a mitogen for human CAFs isolated from hepatic metastases of colorectal cancer. The tyrosine kinase inhibitor imatinib mesylate (1 microM) abrogated the PDGF-induced DNA synthesis, and furthermore counteracted an inhibitory effect of PDGF on the expression of alpha-smooth muscle actin (alpha-SMA). High-dose imatinib mesylate (10 microM) decreased the viability of CAFs in vitro independent from co-stimulation with PDGF. Interestingly, imatinib mesylate (10 microM) strikingly induced the expression of the pro-inflammatory and pro-angiogenic cytokines interleukin (IL)-6 and IL-8, and mildly stimulated the release of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Our results suggest that imatinib mesylate, due to its anti-proliferative activity, may be effective in combination with other substances for the treatment of colorectal metastasis progression.

Stromal fibroblasts in colorectal liver metastases originate from resident fibroblasts and generate an inflammatory microenvironment.

Cancer-associated stromal fibroblasts (CAFs) are the main cellular constituents of reactive stroma in primary and metastatic cancer. We analyzed phenotypical characteristics of CAFs from human colorectal liver metastases (CLMs) and their role in inflammation and cancer progression. CAFs displayed a vimentin(+), alpha-smooth-muscle actin(+), and Thy-1(+) phenotype similar to resident portal-located liver fibroblasts (LFs). We demonstrated that CLMs are inflammatory sites showing stromal expression of interleukin-8 (IL-8), a chemokine related to invasion and angiogenesis. In vitro analyses revealed a striking induction of IL-8 expression in CAFs and LFs by tumor necrosis factor-alpha (TNF-alpha). The effect of TNF-alpha on CAFs is inhibited by the nuclear factor-kappaB inhibitor parthenolide. Conditioned medium of CAFs and LFs similarly stimulated the migration of DLD-1, Colo-678, HuH7 carcinoma cells, and human umbilical vein endothelial cells in vitro. Pretreatment of CAFs with TNF-alpha increased the chemotaxis of Colo-678 colon carcinoma cells by conditioned medium of CAFs; however, blockage of IL-8 activity showed no inhibitory effect. In conclusion, these data raise the possibility that the majority of CAFs in CLM originate from resident LFs. TNF-alpha-induced up-regulation of IL-8 via nuclear factor-kappaB in CAFs is an inflammatory pathway, potentially permissive for cancer invasion that may represent a novel therapeutic target.