Expression and prognostic value of circulating angiogenic cytokines in pancreatic cancer

Circulating Biomarkers Involved in the Development of and Progression to Chronic Pancreatitis-A Literature Review

Chronic pancreatitis (CP) is the end-stage of continuous inflammation and fibrosis in the pancreas evolving from acute- to recurrent acute-, early, and, finally, end-stage CP. Currently, prevention is the only way to reduce disease burden. In this setting, early detection is of great importance. Due to the anatomy and risks associated with direct sampling from pancreatic tissue, most of our information on the human pancreas arises from circulating biomarkers thought to be involved in pancreatic pathophysiology or injury. The present review provides the status of circulating biomarkers involved in the development of and progression to CP.

Pancreatic Cancer and Platelets Crosstalk: A Potential Biomarker and Target

Platelets have been recognized as key players in hemostasis, thrombosis, and cancer. Preclinical and clinical researches evidenced that tumorigenesis and metastasis can be promoted by platelets through a wide variety of crosstalk between cancer cells and platelets. Pancreatic cancer is a devastating disease with high morbidity and mortality worldwide. Although the relationship between pancreatic cancer and platelets in clinical diagnosis is described, the interplay between pancreatic cancer and platelets, the underlying pathological mechanism and pathways remain a matter of intensive study. This review summaries recent researches in connections between platelets and pancreatic cancer. The existing data showed different underlying mechanisms were involved in their complex crosstalk. Typically, pancreatic tumor accelerates platelet aggregation which forms thrombosis. Furthermore, extracellular vesicles released by platelets promote communication in a neoplastic microenvironment and illustrate how these interactions drive disease progression. We also discuss the advantages of novel model organoids in pancreatic cancer research. A more in-depth understanding of tumor and platelets crosstalk which is based on organoids and translational therapies may provide potential diagnostic and therapeutic strategies for pancreatic cancer progression.

Predictive value of EGF and uPAR for chemoradiotherapy response and survival in patients with esophageal squamous cell carcinoma

Background

Chemoradiotherapy (CRT) plays a central role in the treatment of esophageal squamous cell carcinoma (ESCC). However, no effective biomarkers have been identified for predict CRT sensitivity and prognosis of patients with ESCC. The aim of this study was to investigate cytokine profiles of epidermal growth factor (EGF) and urokinase plasminogen activator receptor (uPAR) in 68 ESCC patients, and to evaluate the clinical utility of these markers.

Methods

This pilot study enrolled 68 patients who received neoadjuvant CRT followed by radical surgery or definitive CRT between 2015 and 2017. Serum specimen was obtained from each patient before treatment and at the time of administration of total doses of 40 Gy. Cytokines expression analyses were performed in pre- and post-treatment serum using human cytokine antibody arrays which contained 120 known tumor-related cytokines.

Results

Seven differentially expressed cytokines identified by cytokine antibody arrays in pre- and post-treatment serum from 4 patients with CRT sensitivity and 4 patients with CRT resistance. Of these, up-regulation of EGF and uPAR in serum at the doses of 40 Gy were associated with adverse clinical outcomes. The predictive value of EGF and uPAR were further assessed in a second set of 60 ESCCs. A total of 68 patients enrolled in this study. The median follow-up duration of these patients was 15.87 months (range, 6.21–23.85 months). Cox multivariate survival analyses revealed that high uPAR ratio after CRT independently predicted progression-free survival (PFS) (HR =3.999, 95% CI: 1.503–10.639, P=0.006) and patients with elevated levels of EGF after CRT exhibited significantly worse overall survival (OS) (HR =2.574, 95% CI: 1.046–6.335, P=0.040). Of note, uPAR expression was significantly positive correlation with EGF expression in pre- and post-treatment serum (P=0.0001, P=0.0038). Patients with both high EGF and uPAR ratios had an inferior PFS and OS, compared to patients with a high EGF ratio only or uPAR ratio only or neither (1-year PFS rate 44.2% vs. 61.4%, 1-year OS rate 64.2% vs. 83.4%, P=0.033 and 0.029, respectively).

Conclusions

The levels of EGF and uPAR in serum are reliable and predictive biomarkers for survival in ESCC patients. Further prospective validation in larger independent cohorts is necessary to fully assess its predictive power. We present the following article in accordance with the REMARK reporting checklist.

Expression of Angiogenic Proteins in Tumor and Stroma Affects Survival in Patients With Gastric Cancer

BACKGROUND

Gastric cancer is one of the most frequent malignancies worldwide. Angiogenic growth factors play a crucial role in mediating the crosstalk between cancer cells and the surrounding microenvironment. In this exploratory study, we investigate the impact of angiogenic proteins within the tumor cell or stroma compartment on survival of patients with gastric cancer.

MATERIALS AND METHODS

In 29 patients, tumor and stromal compartments were separated using laser capture microdissection. Angiogenic protein expression was measured using a bead-based immunoassay and correlated with tumor stage and overall survival.

RESULTS

Overall survival was significantly shorter in patients with a high stroma concentration of vascular endothelial growth factor (VEGF)-A (23.5 (±17.6) versus 33.6 (±21.0) mo; P = 0.009) and stem cell factor (22.2 (±18.5) versus 33.6 (±21.8) mo; P = 0.01) compared with patients with a low stroma concentration. High stromal VEGF-D showed a trend toward worse survival (26.8 (±22.0) versus 37.2 (±19.0) mo; P = 0.09). We did not observe any significant correlation between tumor-specific expression of angiogenic cytokines and survival.

CONCLUSIONS

This translational study highlights the difference in clinical impact between tumor and stromal expression of angiogenic proteins. Compartment-specific concentrations of VEGF-A and stem cell factor affect the clinical prognosis and help to identify the best therapy for patients with gastric cancer.

Serum Platelet-Derived Growth Factor Is Significantly Lower in Patients with Lung Cancer and Continued to Decrease After Platinum-Based Chemotherapy

Objective

This study aimed to investigate the diagnosis and prediction of serum platelet-derived growth factor (PDGF) level in patients with lung cancer (LC).

Methods

Serum concentrations of PDGF-AA and PDGF-AB/BB were determined via Luminex assay in 210 patients with non-small cell lung cancer (NSCLC), 33 patients with small cell lung cancer (SCLC), and 168 healthy controls.

Results

The serum levels of PDGF-AA and PDGF-AB/BB were lower in patients with NSCLC (P < 0.05) and SCLC (P < 0.05), compared to healthy controls. The concentration of PDGF-AA or PDGF-AB/BB continued to markedly decrease in NSCLC after therapy with platinum-based chemotherapy (P < 0.05). The median survival times were 29 and 38 months in patients with NSCLC who received PDGF-AA < 30 ng/mL and PDGF-AA ≥ 30 ng/mL (P = 0.0078), and 26 and 38 months in patients with NSCLC who received PDGF-AB/BB < 42 ng/mL and PDGF-AB/BB ≥ 42 ng/mL (P = 0.0001), respectively. At the individual protein level, PDGF-AA and PDGF-AB/BB had better diagnostic values for NSCLC (AUC = 0.905, AUC = 0.922, respectively).

Conclusion

Serum PDGF may be a potential biomarker for diagnosis of patients with NSCLC and SCLC. However, the prognostic value of serum PDGF in patients with NSCLC harboring mutations and different therapies requires additional investigation.

Inflammatory cytokines and combined biomarker panels in pancreatic ductal adenocarcinoma: Enhancing diagnostic accuracy

Background

Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) is challenged by the absence of accurate early diagnostic and prognostic biomarkers. CA19-9 is the established, diagnostic tumour marker in PDAC, despite its limitations. Effective primary screening using circulating biomarker panels have only been considered in a handful of studies and we investigated whether combinations of inflammatory cytokines and angiogenic factors in multivariate logistic models could facilitate earlier diagnosis in our South African setting.

Methods

Plasma levels of 38 cytokines and angiogenic factors were measured in 131 Black South African patients, 85 with PDAC, 25 with benign biliary pathology (BBP) and 21 benign non-HPB controls (BC), by use of human magnetic multiplex screening assays. Multivariate biomarker panels were developed by identifying the top performing biomolecules from univariate logistic regression. Receiver-operator characteristic (ROC) curves and area under the ROC curve (AUC) are reported.

Results

Classification modelling to distinguish PDAC patients from BC showed that a panel of CA19-9 and CXCL10 (IP-10) demonstrated improved diagnostic power over CA19-9 alone (AUC = 0.977 vs. AUC = 0.807, p-value = 0.001). A combined panel including age, BMI and IL-15 showed significant diagnostic power in discriminating PDAC from BBP (AUC = 0.952, p < 0.0001). Finally, a combined panel of IL-8, IL-15 and gender demonstrated diagnostic accuracy (AUC = 0.830, p < 0.0001) in distinguishing PDAC in the presence of jaundice from benign controls with either jaundice, choledocholithiasis or common bile duct injury.

Conclusions

Combined biomarker panels improve diagnostic accuracy in PDAC. In addition to CA19-9, cytokines CXCL10, IL-8 and IL-15 are strong additions to diagnostic biomarker panels in PDAC in Black South Africans.

Serum PlGF and EGF are independent prognostic markers in non-metastatic colorectal cancer

The aim of this study was to determine the prognostic value of circulating angiogenic cytokines in non-metastatic colorectal cancer (CRC) patients. Preoperative serum samples of a training (TC) (n = 219) and a validation cohort (VC) (n = 168) were analyzed via ELISA to determine PlGF, EGF, VEGF, Ang1, PDGF-A, PDGF-B, IL-8 and bFGF levels. In addition, survival was correlated with PlGF and EGF expression measured by microarray and RNAseq in two publicly available, independent cohorts (n = 550 and n = 463, respectively). Prognostic values for overall (OS) and disease-free survival (DFS) were determined using uni- and multivariate Cox proportional hazard analyses. Elevated PlGF is predictive for impaired OS (TC: HR 1.056; p = 0.046; VC: HR 1.093; p = 0.001) and DFS (TC: HR 1.052; p = 0.029; VC: HR 1.091; p = 0.009). Conversely, elevated EGF is associated with favorable DFS (TC: HR 0.998; p = 0.045; VC: HR 0.998; p = 0.018) but not OS (TC: p = 0.201; VC: p = 0.453). None of the other angiogenic cytokines correlated with prognosis. The prognostic value of PlGF (OS + DFS) and EGF (DFS) was confirmed in both independent retrospective cohorts. Serum PlGF and EGF may serve as prognostic markers in non-metastatic CRC.

Low-Dose Continuous 5-Fluorouracil Combined with Leucovorin, nab-Paclitaxel, Oxaliplatin, and Bevacizumab for Patients with Advanced Pancreatic Cancer: A Retrospective Analysis

BACKGROUND

Continuous-infusion 5-fluorouracil (5FU) and calcium leucovorin plus nab-paclitaxel and oxaliplatin have been shown to be active in patients with pancreatic cancer. As a protracted low-dose infusion, 5FU is antiangiogenic, and has synergy with bevacizumab. As shown in the treatment of breast cancer, bevacizumab and nab-paclitaxel are also synergetic.

OBJECTIVE

In this paper we retrospectively analyze the survival of 65 patients with advanced pancreatic cancer who were treated with low-dose continuous (metronomic) chemotherapy given in conjunction with conventional anti-VEGF therapy.

PATIENTS AND METHODS

Since July of 2008, we have treated 65 patients with 5FU (180 mg/m2/day × 14 days) via an ambulatory pump. Calcium leucovorin (20 mg/m2 IV), nab-paclitaxel (60 mg/m2) IV as a 30-min infusion, and oxaliplatin (50 mg/m2) IV as a 60-min infusion were given on days 1, 8, and 15. Bevacizumab (5 mg/kg) IV over 30 min was administered on days 1 and 15. Cycles were repeated every 28-35 days. There were 42 women and 23 men, and the median age was 59 years. Forty-six patients had stage IV disease.

RESULTS

The median survival was 19 months, with 82% of patients surviving 12 months or longer. The overall response rate was 49%. There were 28 patients who had received prior treatment, 15 of whom responded to therapy. Fifty-two patients had elevated CA 19-9 prior to treatment. Of these, 21 patients had 90% or greater reduction in CA 19-9 levels. This cohort had an objective response rate of 71% and a median survival of 27 months. Thirty patients stopped treatment due to disease progression, and an additional 22 stopped because of toxicity. One patient died while on therapy.

CONCLUSIONS

This non-gemcitabine-based regimen resulted in higher response rates and better survival than what is commonly observed with therapy given at conventional dosing schedules. Low-dose continuous (metronomic therapy) cytotoxic chemotherapy combined with antiangiogenic therapy is safe and effective.

Autocrine DUSP28 signaling mediates pancreatic cancer malignancy via regulation of PDGF-A

Pancreatic cancer remains one of the most deadly cancers with a grave prognosis. Despite continuous efforts to improve remedial values, limited progress has been made. We have reported that dual specificity phosphatase 28 (DUSP28) has a critical role of chemo-resistance and migration in pancreatic cancers. However, its mechanism remains unclear. Here, we further clarify the function of DUSP28 in pancreatic cancers. Analysis using a public microarray database and in vitro assay indicated a critical role of platelet derived growth factor A (PDGF-A) in pancreatic cancer malignancy. PDGF-A was positively regulated by DUSP28 expression at the mRNA and protein levels. Enhanced DUSP28 sensitized pancreatic cancer cells to exogenous PDGF-A treatment in migration, invasion, and proliferation. Transfection with siRNA targeting DUSP28 blunted the influence of administered PDGF-A by inhibition of phosphorylation of FAK, ERK1/2, and p38 signalling pathways. In addition, DUSP28 and PDGF-A formed an acquired autonomous autocrine-signaling pathway. Furthermore, targeting DUSP28 inhibited the tumor growth and migratory features through the blockade of PDGF-A expression and intracellular signaling in vivo. Our results establish novel insight into DUSP28 and PDGF-A related autonomous signaling pathway in pancreatic cancer.

Postoperative course and prognostic value of circulating angiogenic cytokines after pancreatic cancer resection

Background

Circulating angiogenic cytokines (CACs) have been confirmed as prognostic biomarkers and therapeutic targets in several solid tumors. However, their role as prognostic biomarkers in resected pancreatic ductal adenocarcinoma (PDAC) is unknown.

Results

The expression of CACs in patients with PDAC differs from those with CP both pre- and postoperatively. Correlation analyses show significant correlations between circulating levels of CACs: VEGF was correlated with IL-6 (r = 0.457), FGF (r = 0.44), G-CSF (r = 0.543), HGF (r = 0.586) and SDF-1α (r = 0.784) before the surgery. The circulating levels of TNF-α correlated with the serum concentration of IL-4 before (r= 0.656) and after the resection (r = 0.776 on POD 3, r = 0.865 on POD 7). Gender did not show any correlation with serum levels of CAC, except for significantly higher levels of EGF in males (P = 0.002). Other clinicopathological variables such as age (< 65 vs. > 65 years), T, N, or UICC stage did not have an association with the cytokine levels. The multivariate model including the entire angiogenic panel revealed that postoperative increasing levels of EGF (P = 0.023), PDGFA-A (P = 0.024), TNF-α (P = 0.001) and IL-8 (P = 0.049) were associated with a favorable prognosis, whereas elevating levels of VEGF (P = 0.005) correlated with a poor cancer-specific survival.

Materials and Methods

Preoperative and postoperative blood samples were collected in patients undergoing surgery for PDAC (n = 40) or chronic pancreatitis (CP; n = 9). Serum levels of 13 angiogenic cytokines (IL-4, IL-6, FGF-b, G-CSF, TNF-α, VEGF, HGF, SDF-1α, IL-8, EGF, Ang-1, PDGF-AA and PlGF) were analyzed using ELISA and Multiplex. Prognostic factors were identified by a Cox proportional hazards model.

Conclusions

Postoperative changes of serum levels of certain angiogenic cytokines correlate with patients’ prognosis after resection for pancreatic cancer. CACs should thus be considered as biomarkers in patients with resected pancreatic cancer.

A new angiogenesis prognostic index with VEGFA, PlGF, and angiopoietin1 predicts survival in patients with advanced gastric cancer

BACKGROUND/AIM

The role of angiogenic factors in gastric cancer is not clear. We aimed to assess the role of vascular endothelial growth factor A (VEGFA), angiopoietin 1 (Ang-1), and placental growth factor (PlGF) in the prognosis of patients with advanced gastric cancer.

MATERIALS AND METHODS

Thirty consecutive patients treated with a modified DCF (docetaxel, cisplatin, and fluorouracil) regimen were included in the study. The plasma VEGFA, Ang-1, and PlGF levels of the patients before treatment and following two cycles of chemotherapy were measured and evaluated as prognostic factors.

RESULTS

Poor performance status and lower Ang-1 levels were correlated with poor overall survival (OS). No significant correlation between VEGFA or PlGF and OS was found. An angiogenesis prognostic index (API) based on the levels of VEGFA, Ang-1, and PlGF was found to be highly correlated with OS. Performance status and API were found as independent prognostic factors for OS. Furthermore, a decrease in VEGFA by 25% from the pretreatment level was also found as a prognostic factor for OS independent of response to DCF regimen.

CONCLUSION

Our results support the use of the new API including VEGFA, Ang-1, and PlGF levels in patients with advanced gastric cancer as a predictor of survival.

Anti-cancer Mechanism of Docosahexaenoic Acid in Pancreatic Carcinogenesis: A Mini-review

Pancreatic cancer is a highly aggressive malignant tumor of the digestive system and radical resection, which is available to very few patients, might be the only possibility for cure. Since therapeutic choices are limited at the advanced stage, prevention is more important for reducing incidence in high-risk individuals with family history of pancreatic cancer. Epidemiological studies have shown that a high consumption of fish oil or ω3-polyunsaturated fatty acids reduces the risk of pancreatic cancers. Dietary fish oil supplementation has shown to suppress pancreatic cancer development in animal models. Previous experimental studies revealed that several hallmarks of cancer involved in the pathogenesis of pancreatic cancer, such as the resistance to apoptosis, hyper-proliferation with abnormal Wnt/β-catenin signaling, expression of pro-angiogenic growth factors, and invasion. Docosahexaenoic acid (DHA) is a ω3-polyunsaturated fatty acid and rich in cold oceanic fish oil. DHA shows anti-cancer activity by inducing oxidative stress and apoptosis, inhibiting Wnt/β-catenin signaling, and decreasing extracellular matrix degradation and expression of pro-angiogenic factors in pancreatic cancer cells. This review will summarize anti-cancer mechanism of DHA in pancreatic carcinogenesis based on the recent studies.

Inflammatory cytokines and angiogenic factors as potential biomarkers in South African pancreatic ductal adenocarcinoma patients: A preliminary report

BACKGROUND/OBJECTIVES

Several studies have investigated the association of differentially expressed cytokines with pancreatic ductal adenocarcinoma (PDAC), but none in African countries. This study aimed at investigating T-helper (Th) cell and angiogenic markers as diagnostic or prognostic biomarkers for PDAC in Black South Africans.

METHODS

We conducted a prospective, case-control study comprising of 34 PDAC patients and 27 control participants with either critical limb ischemia, abdominal aortic aneurysm or other abdominal pathology from causes other than pancreatic disease. Plasma levels of IL-2, IL-4, IL-6, IL-10, TNF, IFN-γ, IL-17A, VEGF, sVEGF-R1, FGF, PIGF, PDGF and P-selectin were measured using commercially available cytometric bead array, ELISA and multi-analyte Luminex kits.

RESULTS

Significantly higher levels of IFN-γ (p < 0.001), TNF (p < 0.001), IL-2 (p = 0.001), IL-4 (p < 0.01), IL-10 (p < 0.01), IL-17A (p < 0.01), PlGF (p < 0.0001) and basic FGF (p < 0.0001) were found in cases compared to control participants. PDAC patients with irresectable tumours had higher levels of VEGF (p = 0.02) and IL-6 (p = 0.01). A univariate analysis showed significant associations between IFN-γ, TNF, IL-10, -4, -2, basic FGF, PlGF and PDAC. In a multivariate logistic regression model, basic FGF (p = 0.002) and PlGF (p = 0.007) were independent risk factors for PDAC with a combined sensitivity of 71% and specificity of 100%.

CONCLUSION

Our preliminary data suggests a potential role for basic FGF and PlGF as diagnostic, and VEGF and IL-6 as prognostic biomarkers of PDAC in Black South African patients.

Diagnostic Value of Serum Angiogenesis Markers in Ovarian Cancer Using Multiplex Immunoassay

As cancer development involves pathological vessel formation, 16 angiogenesis markers were evaluated as potential ovarian cancer (OC) biomarkers. Blood samples collected from 172 patients were divided based on histopathological result: OC (n = 38), borderline ovarian tumours (n = 6), non-malignant ovarian tumours (n = 62), healthy controls (n = 50) and 16 patients were excluded. Sixteen angiogenesis markers were measured using BioPlex Pro Human Cancer Biomarker Panel 1 immunoassay. Additionally, concentrations of cancer antigen 125 (CA125) and human epididymis protein 4 (HE4) were measured in patients with adnexal masses using electrochemiluminescence immunoassay. In the comparison between OC vs. non-OC, osteopontin achieved the highest area under the curve (AUC) of 0.79 (sensitivity 69%, specificity 78%). Multimarker models based on four to six markers (basic fibroblast growth factor-FGF-basic, follistatin, hepatocyte growth factor-HGF, osteopontin, platelet-derived growth factor AB/BB-PDGF-AB/BB, leptin) demonstrated higher discriminatory ability (AUC 0.80-0.81) than a single marker (AUC 0.79). When comparing OC with benign ovarian tumours, six markers had statistically different expression (osteopontin, leptin, follistatin, PDGF-AB/BB, HGF, FGF-basic). Osteopontin was the best single angiogenesis marker (AUC 0.825, sensitivity 72%, specificity 82%). A three-marker panel consisting of osteopontin, CA125 and HE4 better discriminated the groups (AUC 0.958) than HE4 or CA125 alone (AUC 0.941 and 0.932, respectively). Osteopontin should be further investigated as a potential biomarker in OC screening and differential diagnosis of ovarian tumours. Adding osteopontin to a panel of already used biomarkers (CA125 and HE4) significantly improves differential diagnosis between malignant and benign ovarian tumours.

Systematic review of peri-operative prognostic biomarkers in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) continues to be associated with a poor prognosis. This systematic review aimed to summarize the literature regarding potential prognostic biomarkers to facilitate validation studies and clinical application.

METHODS

A systematic review was performed (2004-2014) according to PRISMA guidelines. Studies were ranked using REMARK criteria and the following outcomes were examined: overall/disease free survival, nodal involvement, tumour characteristics, metastasis, recurrence and resectability.

RESULTS

256 biomarkers were identified in 158 studies. 171 biomarkers were assessed with respect to overall survival: urokinase-type plasminogen activator receptor, atypical protein kinase C and HSP27 ranked the highest. 33 biomarkers were assessed for disease free survival: CD24 and S100A4 were the highest ranking. 17 biomarkers were identified for lymph node involvement: Smad4/Dpc4 and FOXC1 ranked highest. 13 biomarkers were examined for tumour grade: mesothelin and EGFR were the highest ranking biomarkers. 10 biomarkers were identified for metastasis: p16 and sCD40L were the highest ranking. 4 biomarkers were assessed resectability: sCD40L, s100a2, Ca 19-9, CEA.

CONCLUSION

This review has identified and ranked specific biomarkers that should be a primary focus of ongoing validation and clinical translational work in PDAC.

Cytokines as Biomarkers of Pancreatic Ductal Adenocarcinoma: A Systematic Review

OBJECTIVES

A systematic review of the role of cytokines in clinical medicine as diagnostic, prognostic, or predictive biomarkers in pancreatic ductal adenocarcinoma was undertaken.

MATERIALS AND METHODS

A systematic review was conducted according to the 2009 PRISMA guidelines. PubMed database was searched for all original articles on the topic of interest published until June 2015, and this was supplemented with references cited in relevant articles. Studies were evaluated for risk of bias using the Quality in Prognosis Studies tools.

RESULTS

Forty one cytokines were investigated with relation to pancreatic ductal adenocarcinoma (PDAC) in 65 studies, ten of which were analyzed by more than three studies. Six cytokines (interleukin[IL]-1β, -6, -8, -10, vascular endothelial growth factor, and transforming growth factor) were consistently reported to be increased in PDAC by more than four studies; irrespective of sample type; method of measurement; or statistical analysis model used. When evaluated as part of distinct panels that included CA19-9, IL-1β, -6 and -8 improved the performance of CA19-9 alone in differentiating PDAC from healthy controls. For example, a panel comprising IL-1β, IL-8, and CA 19-9 had a sensitivity of 94.1% vs 85.9%, specificity of 100% vs 96.3%, and area under the curve of 0.984 vs 0.925. The above-mentioned cytokines were associated with the severity of PDAC. IL-2, -6, -10, VEGF, and TGF levels were reported to be altered after patients received therapy or surgery. However, studies did not show any evidence of their ability to predict treatment response.

CONCLUSION

Our review demonstrates that there is insufficient evidence to support the role of individual cytokines as diagnostic, predictive or prognostic biomarkers for PDAC. However, emerging evidence indicates that a panel of cytokines may be a better tool for discriminating PDAC from other non-malignant pancreatic diseases or healthy individuals.

Comprehensive Analysis of Serum microRNAs in Autoimmune Pancreatitis

BACKGROUND/AIMS

Autoimmune pancreatitis (AIP) is a rare disease that has recently emerged as a unique type of pancreatitis with a presumed autoimmune etiology. MicroRNA (miRNA) is a small non-coding RNA that targets multiple mRNAs. miRNAs might exist in serum in a stabilized form, suggesting its potential application as a biomarker. We here examined the miRNA expression profile in the serum of patients with AIP.

METHODS

miRNAs were prepared from serum samples of patients with various pancreatic diseases (AIP (n = 3, each before and after the steroid therapy), chronic pancreatitis (n = 5), pancreatic cancer (n = 5)) or healthy controls (n = 5). A human miRNA Oligo chip containing approximately 2,000 miRNAs was used to identify differentially expressed miRNAs. Ingenuity Pathway Analysis (IPA) was used for the integrated analysis of altered miRNAs.

RESULTS

Microarray analysis identified miRNAs highly expressed in the serum of patients with AIP: 13 miRNAs vs. CP, 204 miRNAs vs. pancreatic cancer, and 19 miRNAs vs. healthy controls. miR-150-5p was commonly upregulated in AIP compared to the other samples. IPA revealed the most biological processes affected by the steroid therapy including cellular development, cellular growth, and cell movement.

CONCLUSION

Our results identified that miRNAs were differentially expressed in the serum of AIP patients.

Prognostic impact of a compartment-specific angiogenic marker profile in patients with pancreatic cancer

Pancreatic cancer consists of a heterogenous bulk of tumor cells and stroma cells which contribute to tumor progression by releasing angiogenic factors. Those factors can be detected as circulating serum factors. We performed a compartment-specific analysis of tumor-derived and stroma-derived angiogenic factors to identify biomarkers and molecular targets for the treatment of pancreatic cancer. Kryo-frozen tissue from primary ductal adenocarcinomas (n = 51) was laser-microdissected to isolate tumor and stroma tissue. Expression of 17 angiogenic factors (angiopoietin-2, follistatin, GCSF, HGF, interleukin-8, leptin, PDGF-BB, PECAM-1, VEGF, matrix metalloproteinase -1, -2, -3, -7, -9, -10, -12, and -13) was analyzed using a multiplex elisa assay for tissue-derived proteins and corresponding serum.

Our study reveals a compartment-specific expression profile for several angiogenic factors and matrix metalloproteinases. ROC analysis of corresponding serum samples reveals MMP-7 and MMP-12 as strong classifiers for the diagnosis of patients with pancreatic cancer vs. healthy control donors. High expression of tumor-derived PDGF-BB and MMP-1 correlates with prolonged survival in univariate and multivariate analysis. In conclusion, a distinct expression patterns for angiogenic cytokines and MMPs in pancreatic cancer and surrounding stroma may implicate them as novel targets for cancer treatment. Tumor-derived PDGF-BB and MMP-1 are significant and independent prognostic markers for poor survival.

Prognostic significance of placenta growth factor expression in patients with multiple cancers: a meta-analysis

BACKGROUND

Placenta growth factor (PLGF) is a member of the vascular endothelial growth factor (VEGF) family which is associated with the progression and metastasis of cancer. However, whether it can be used to predict prognosis in multiple cancer is still inconsistent.

METHODS

A meta-analysis was performed by searching electronic databases updated to December 2014. Eligible studies which evaluated the relationship between PLGF expression level and survival of patients with multiple cancers were conducted. Overall survival (OS), progression-free survival (PFS), hazard ratio (HR), and 95% confidence intervals (CI) were calculated.

RESULTS

Nineteen studies with a variety of cancers were included for the meta-analysis. Combined HR suggested that high expression of PLGF significantly associated with a poor OS (HR=1.69, 95% CI, 1.32-2.16), and PFS (HR=1.8, 95% CI, 1.33-2.44) in patients with different cancers. Moreover, a subgroup analysis based on cancer type demonstrated that high expression level of PLGF predict poor OS in both digestive system carcinoma (HR=1.63, 95% CI, 1.21-2.19; I(2)=80.7%, P<0.001) and respiratory system tumor (HR=1.75, 95% CI, 1.28-2.41; I(2)=0.0%, P=0.394). For PFS, the similar result was found in respiratory system tumor (HR=1.64, 95% CI, 1.23-2.19; I(2)=0.0%, P=0.807), but not in digestive system carcinoma (HR=1.81, 95% CI, 0.93-3.52; I(2)=80.2%, P<0.001).

CONCLUSION

Our meta-analysis demonstrates that PLGF might be regarded as a poor prognostic fact for multiple cancers. More large-scale and well-designed studies are still needed to strengthen our findings.

PDGF receptors in tumor biology: prognostic and predictive potential

PDGF receptors (PDGFRs) exert cell type-specific effects in many different tumor types. They are emerging as key regulators of mesenchymal cells of the tumor microenvironment, and of many common malignancies, such as cancer of the breast, colon and prostate. In some tumor types PDGFRs are genetically activated and are thus directly involved in stimulation of malignant cell growth. Recent studies have uncovered clinically relevant variations in stromal PDGFR expression. High stromal PDGFRβ expression or activation is associated with poor prognosis in breast and prostate cancer. Indications of prognostic significance of stromal PDGFRβ expression in various GI tract tumor types also exist. The prognostic significance of PDGFRα and β in malignant cells of common epithelial tumor types should be further studied. Collectively data suggest that continued characterization of PDGFR expression in human tumors should present opportunities for improved accuracy in prognosis and also allow novel biomarker-based clinical studies exploring the efficacy of PDGFR-directed tumor therapies.

Effect of resection of localized pancreaticobiliary adenocarcinoma on angiogenic markers and tissue factor related pro-thrombotic and pro-angiogenic activity

In this study, 52 patients were studied to elucidate the relative impact of resection of localized pancreaticobiliary adenocarcinoma (PBC) on circulating factors of tumour-associated angiogenesis e.g. tissue factor bearing microparticles (TFMP) and vascular endothelial growth factor (VEGF) and their clinicopathological significance to angiogenesis markers in cancer tissue from PBC patients. Angiogenesis array analysis on serum samples revealed that surgical resection of tumour lesion in PBC patients affects the levels of a panel of angiogenesis-related molecules, including VEGF that was verified by ELISA to significantly reduce (median & IQR: 1003(369-2000) vs. 457(159-834) pg/ml; p<0.05). Correspondingly, a significant decrease in the angiogenic activity (decreased capillary tube formation; p<0.05) of serum samples after the surgery was also found. Despite a decrease in number of circulating TFMP after surgery, this did not reach statistical significance; there was a significant reduction in pro-coagulant activity (prolonged prothrombin time, p<0.001) post-operatively. In addition, the activity of total microparticles (MP activity assay, p<0.05) was decreased significantly. Immunohistochemical staining of tumour tissue revealed a strong correlation between the microvessel density (MVD) and VEGF expression. Also, higher levels of circulating TFMP or TF related activity (prothrombin time) correlated significantly with TF expression and MVD on tumour tissues from PBC patients. These findings suggest that in pancreaticobiliary adenocarcinoma TF related angiogenesis drivers are equally significant to VEGF ones, raising the clinical question of whether the effectiveness of angiogenesis targeting studies could be improved through the 'dual' targeting of these pathways in PBC.

Expression of growth‑regulated oncogene‑1, hepatocyte growth factor, platelet‑derived growth factor‑AA and soluble E‑selectin and their association with high‑risk human papillomavirus infection in squamous cell carcinoma of the uterine cervix

The aim of the present study was to evaluate the clinical significance and prognostic value of growth‑regulated oncogene‑1 (GRO‑1), hepatocyte growth factor (HGF), platelet‑derived growth factor‑AA (PDGF‑AA), soluble E‑selectin (sE‑selectin) and high‑risk human papillomavirus (HPV; types 16, 18/45, 31 and 33/52/58/67) infection in cervical squamous cell carcinoma (CSCC). A total of 426 cases were enrolled in the present study, of which 292 cases were patients with CSCC, 43 were patients with cervical intraepithelial neoplasia (CIN) and 91 were healthy controls. Luminex xMAP technology was used to detect the serum levels of GRO‑1, HGF, PDGF‑AA and sE‑selectin in all cases and two‑channel fluorescence quantitative polymerase chain reaction was used to determine HPV DNA in cervical scrapings from CSCC and CIN patients. The results demonstrated that the serum levels of GRO‑1, HGF and sE‑selectin were significantly higher in patients with CSCC compared with patients with CIN and the healthy controls (P<0.0001). Compared with the CIN patients, the HPV positive rate in the CSCC patients significantly increased (P=0.013). The four factors were correlated with certain clinicopathological variables of CSCC patients to a certain degree (P<0.05) and the levels of HGF were closely associated with HPV infection (P=0.039). The receiver operating characteristic curves demonstrated that HGF obtained the highest diagnostic value compared with the other three factors. Multivariate Cox regression analysis demonstrated that the serum levels of HGF (P<0.0001), FIGO stage (P<0.0001) and pelvic lymph node metastasis (P=0.001) were independent prognostic factors in patients with CSCC, while high‑risk HPV infection did not show any significance in this analysis. These results demonstrated that HGF may be a useful prognostic biomarker rather than high‑risk HPV types in patients with CSCC.

Identification and elimination of target-related matrix interference in a neutralizing anti-drug antibody assay

Biopharmaceuticals administered to the human body have the potential to trigger the production of anti-drug (also called anti-therapeutic) antibodies (ADA) that can neutralize the therapeutic activity. For antibody therapeutics, cell-based neutralizing ADA assays are frequently used to evaluate ADA in clinical studies. We developed a method to detect neutralizing antibodies against MEDI-575, a fully human IgG2κ antagonistic antibody against PDGFR-α. We evaluated three assay formats, two of which measured late responses, cell proliferation and apoptosis, whereas the third assay detected an early signaling event, phosphorylation of PDGFR-α. Measuring phosphorylation provided a superior assay window and therefore was developed as a neutralizing ADA (NAb) assay. Matrix interference, however, was significant, and could be identified to be caused by PDGF-AA and PDGF-AB, apparently the two most abundant ligands of PDGFR-α present in human serum samples. A simple pre-treatment step, addition of an inhibitory antibody to PDGF-A, a subunit present in PDGF-AA and PDGF-AB, was found to eliminate matrix interference, increasing assay reliability and sensitivity. We integrated the pre-treatment step into assay development and qualified a robust NAb assay.

Serum protein profile at remission can accurately assess therapeutic outcomes and survival for serous ovarian cancer

BACKGROUND

Biomarkers play critical roles in early detection, diagnosis and monitoring of therapeutic outcome and recurrence of cancer. Previous biomarker research on ovarian cancer (OC) has mostly focused on the discovery and validation of diagnostic biomarkers. The primary purpose of this study is to identify serum biomarkers for prognosis and therapeutic outcomes of ovarian cancer.

EXPERIMENTAL DESIGN

Forty serum proteins were analyzed in 70 serum samples from healthy controls (HC) and 101 serum samples from serous OC patients at three different disease phases: post diagnosis (PD), remission (RM) and recurrence (RC). The utility of serum proteins as OC biomarkers was evaluated using a variety of statistical methods including survival analysis.

RESULTS

Ten serum proteins (PDGF-AB/BB, PDGF-AA, CRP, sFas, CA125, SAA, sTNFRII, sIL-6R, IGFBP6 and MDC) have individually good area-under-the-curve (AUC) values (AUC = 0.69-0.86) and more than 10 three-marker combinations have excellent AUC values (0.91-0.93) in distinguishing active cancer samples (PD & RC) from HC. The mean serum protein levels for RM samples are usually intermediate between HC and OC patients with active cancer (PD & RC). Most importantly, five proteins (sICAM1, RANTES, sgp130, sTNFR-II and sVCAM1) measured at remission can classify, individually and in combination, serous OC patients into two subsets with significantly different overall survival (best HR = 17, p<10(-3)).

CONCLUSION

We identified five serum proteins which, when measured at remission, can accurately predict the overall survival of serous OC patients, suggesting that they may be useful for monitoring the therapeutic outcomes for ovarian cancer.

Multifarious functions of PDGFs and PDGFRs in tumor growth and metastasis

Platelet-derived growth factors (PDGFs) and their receptors (PDGFRs) are frequently expressed in various tumors and their expression levels correlate with tumor growth, invasiveness, drug resistance, and poor clinical outcomes. Emerging experimental evidence demonstrates that PDGFs exhibit multiple functions in modulation of tumor growth, metastasis, and the tumor microenvironment by targeting malignant cells, vascular cells, and stromal cells. Understanding PDGF-PDGFR-mediated molecular signaling may provide new mechanistic rationales for optimizing current cancer therapies and the development of future novel therapeutic modalities.

Reduction in circulating pro-angiogenic and pro-inflammatory factors is related to improved outcomes in patients with advanced pancreatic cancer treated with gemcitabine and intravenous omega-3 fish oil

BACKGROUND

Pancreatic cancer is a rapidly progressive disease which is often only amenable to palliative treatment. Few patients respond to palliative chemotherapy, so surrogate markers indicating which patients are likely to respond to treatment are required. There is a well-established link between pro-inflammatory circulating cytokines and growth factors (CAF), and the development of neoplasia. Agents that may modulate these factors are of interest in developing potential novel therapeutic applications.

METHODS

As part of a single-arm phase II trial in patients with advanced pancreatic cancer (APC) treated with gemcitabine and intravenous (i.v.) omega-3 rich lipid emulsion (n-3FA), serum samples were analysed for 14 CAF using a multiplex cytokine array. Baseline serum concentrations were correlated with overall (OS) and progression-free survival (PFS), and changes in concentration correlated with time and outcomes for CAF responders were analysed.

RESULTS

Platelet-derived growth factor (PDGF) and fibroblast growth factor (FGF) concentrations reduced significantly with treatment over time. Low baseline interleukin (IL)-6 and -8 were correlated with improved OS. PDGF responders showed a tendency towards improved OS and FGF responders a significantly improved PFS.

DISCUSSION

Treatment with gemcitabine plus i.v. n-3FA may reduce concentrations of CAF which may be associated with an improved outcome. Baseline IL-6 and -8 may be surrogate markers for outcome in patients with APC treated with this regimen.

STAT5b as molecular target in pancreatic cancer--inhibition of tumor growth, angiogenesis, and metastases

The prognosis of patients suffering from pancreatic cancer is still poor and novel therapeutic options are urgently needed. Recently, the transcription factor signal transducer and activator of transcription 5b (STAT5b) was associated with tumor progression in human solid cancer. Hence, we assessed whether STAT5b might serve as an anticancer target in ductal pancreatic adenocarcinoma (DPAC). We found that nuclear expression of STAT5b can be detected in approximately 50% of DPAC. Blockade of STAT5b by stable shRNA-mediated knockdown showed no effects on tumor cell growth in vitro. However, inhibition of tumor cell motility was found even in response to stimulation with epidermal growth factor or interleukin-6. These findings were paralleled by a reduction of prometastatic and proangiogenic factors in vitro. Subsequent in vivo experiments revealed a strong growth inhibition on STAT5b blockade in subcutaneous and orthotopic models. These findings were paralleled by impaired tumor angiogenesis in vivo. In contrast to the subcutaneous model, the orthotopic model revealed a strong reduction of tumor cell proliferation that emphasizes the meaning of assessing targets in an appropriate microenvironment. Taken together, our results suggest that STAT5b might be a potential novel target for human DPAC.

Erythropoietin in cancer: a dilemma in risk therapy

Erythropoietin (EPO) is a frequently prescribed drug for treatment of cancer-related and chemotherapy-induced anemia in cancer patients. Paradoxically, recent preclinical and clinical studies indicate that EPO could potentially accelerate tumor growth and jeopardize survival in cancer patients. In this review I critically discuss the current knowledge and broad biological functions of EPO in association with tumor growth, invasion, and angiogenesis. The emphasis is focused on discussing the complex interplay between EPO and other tumor-derived factors in angiogenesis, tumor growth, invasion, and metastasis. Understanding the multifarious functions of EPO and its reciprocal relation with other signaling pathways is crucial for developing more effective agents for cancer therapy and for minimizing risks for cancer patients.

RNA interference-mediated silencing of VEGF and bFGF suppresses endostatin secretion in pancreatic carcinoma cells

Pro-angiogenic factors [vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF)] and anti-angiogenic factors (endostatin) play important roles in the progression of pancreatic cancer. The purpose of the present study was to investigate the knockdown effect by either VEGF or bFGF siRNA on the expression and secretion of endostatin in pancreatic carcinoma cells. Pancreatic carcinoma cell lines (sw1990, Panc-1 and PCT-3) were treated with VEGF and bFGF siRNA. The expression of VEGF, bFGF and endostatin in pancreatic carcinoma cell lines was determined by reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis. Secretion of endostatin was measured by enzyme-linked immunosorbent assay (ELISA). bFGF and VEGF siRNA significantly reduced the expression of bFGF and VEGF mRNA, respectively, but did not affect mRNA and protein expression of endostatin in pancreatic carcinoma cell lines. However, secretion of endostatin in PCT-3, Panc-1 and sw1990 cells was significantly inhibited by bFGF and VEGF siRNA. This study demonstrated that pro-angiogenic factors (VEGF and bFGF) differentially modulate expression and secretion of anti-angiogenic factors (endostatin). This result may have important implications in the anti-angiogenesis therapy in pancreatic cancer.

Microenvironment elements involved in the development of pancreatic cancer tumor

Introduction. In spite of intensive research during many years, pancreatic adenocarcinoma remains one of the deadliest cancers. The surgical intervention remains main possibility of treatment because chemotherapy and radiotherapy has a minimal impact on long-term survival. We are still looking for the weak points of this devastating disease. Materials and Methods. Pancreatic tumor tissue samples were collected from 36 patients. Immunohistochemistry staining was used to evaluate expression of growth factors and immune infiltrates. Activity of MMP2 and MMP9 was assessed by gelatin zymography on 7.5% SDS-PAGE gel with 0.1% gelatin. Results. All growth factors were strongly expressed in pancreatic tumor tissue. We found that level of expression of c-Met receptor was higher for G3 tumors than for G2 tumors. Also we found that active MMP2 was present at all stages of tumor while active MMP9 just at more advanced tumors. Abundant immune cells infiltration was distinctive for tumor tissue, especially macrophages were infiltrating tumor tissue. We found that amount of macrophages was associated with lymph nodes metastases. Conclusion. In our research we demonstrated that among many factors influencing tumor microenvironment c-Met receptor, infiltrating macrophages and MMP2 have significant influence on development and invasion of pancreatic cancer.

Clinical implications of biological markers in Pancreatic Ductal Adenocarcinoma

Pancreatic Ductal Adenocarcinoma (PDAC) is a malignant neoplasm and is the fourth leading cause of cancer-related deaths in US with a 5-year survival rate less than 5%. Surgery is the only potentially curative treatment even though the result is a palliation in the majority of cases and the majority of lesions are lately diagnosed. Progression from normal pancreatic epithelium to metastatic disease is now a well-characterized sequence of events. Research has shown that pancreatic cancer is fundamentally a genetic disease with several biological pathway implied in apoptosis, cell proliferation and self-sufficiency in growth signaling, but how those findings could be applied in daily clinical practice remain unknown. Several studies tried to characterize diagnostic and prognostic biomarkers in PDAC to make it possible an earlier diagnosis, guarantee a more effective treatment and reach a better prognosis even though the results remain contrasting. The main limit of the published researches is the small number of patients studied, but even the heterogeneity of the used methods of analysis. Examining critically the research of the last years future trials may be addressed toward a translational models integrating "the bench and the bed" with the clinical experience and drive the basic research toward the clinical applications.

Analysis of pancreatic cancer microenvironment: role of macrophage infiltrates and growth factors expression

Background: Research over the last twenty years has yielded much insight into pancreatic cancer biology, but it has neither improved diagnostics methods nor the way of treatment. The question remains as to what the critical deciding factor is in making pancreatic cancer such an aggressive disease.

Methods: Pancreatic tumor tissue came from 36 patients. To assess lymphatic vessels color lymphangiography and immunohistochemistry were used. Activity of matrix metalloproteinases was studied with gel and in situ zymography. Expression of growth factors and infiltrating immune cells were investigated using immunohistochemistry.

Results: Our study revealed that the structures that correspond to lymphatic vessels were not observed in tumor center but only at the edge of the tumor. All studied growth factors were present in tumor tissue. We found that the difference in expression between G2 and G3 stage was statistically relevant in cases of c-Met receptor. Inflammatory cells were present around neoplastic glands and also strongly around nerves infiltrated by cancer cells. The number of infiltrating macrophages in tumor tissue was significantly higher in group with metastases to lymph nodes.

Conclusion: We showed two factors that influence pancreatic cancer progression and invasion: c-Met receptors and macrophages infiltrating tumor tissue. Based on our analysis, this indicates that epithelial-mesenchymal transition might be crucial in the progression of pancreatic cancer.