The basal nutritional state of PDAC patients is the dominant factor for completing adjuvant chemotherapy

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is highly lethal, and several clinical trials have shown that adjuvant chemotherapy after curative resection can improve the prognosis of these patients. However, the adjuvant chemotherapy completion rate is less than satisfactory. If this rate could be increased then the overall prognosis of PDAC might be improved; however, reports addressing this problem are insufficient. To elucidate the factors, we retrospectively investigated PDAC patients.

METHODS

Various factors of 121 PDAC patients undergoing R0 resection, including preoperatively treated patients, were investigated. Univariate and multivariate analyses were performed to investigate the factors that were associated with the completion of adjuvant chemotherapy.

RESULTS

The analysis identified age and the prognostic nutritional index (PNI) as significant independent factors. A receiver operating characteristic curve analysis of age yielded a cutoff value of 67 years (sensitivity, 64%; specificity, 78%). Univariate and multivariate analyses of the 61 patients who were over 67 years of age revealed that the PNI (odds ratio, 0.85; P = 0.048) and Evans grade (odds ratio, 0.041; P = 0.0010) were significant factors for the completion of chemotherapy.

CONCLUSIONS

The results of our investigation suggest that nutrition should be controlled in older PDAC patients to facilitate the completion of adjuvant chemotherapy.

Oncogenic KRas-induced Increase in Fluid-phase Endocytosis is Dependent on N-WASP and is Required for the Formation of Pancreatic Preneoplastic Lesions

Fluid-phase endocytosis is a homeostatic process with an unknown role in tumor initiation. The driver mutation in pancreatic ductal adenocarcinoma (PDAC) is constitutively active KRasG12D, which induces neoplastic transformation of acinar cells through acinar-to-ductal metaplasia (ADM). We have previously shown that KRasG12D-induced ADM is dependent on RAC1 and EGF receptor (EGFR) by a not fully clarified mechanism. Using three-dimensional mouse and human acinar tissue cultures and genetically engineered mouse models, we provide evidence that (i) KRasG12D leads to EGFR-dependent sustained fluid-phase endocytosis (FPE) during acinar metaplasia; (ii) variations in plasma membrane tension increase FPE and lead to ADM in vitro independently of EGFR; and (iii) that RAC1 regulates ADM formation partially through actin-dependent regulation of FPE. In addition, mice with a pancreas-specific deletion of the Neural-Wiskott-Aldrich syndrome protein (N-WASP), a regulator of F-actin, have reduced FPE and impaired ADM emphasizing the in vivo relevance of our findings. This work defines a new role of FPE as a tumor initiating mechanism.

Endoscopic Evaluation in the Workup of Pancreatic Cancer

Early diagnosis and accurate staging of pancreatic cancer is very important to plan optimal management strategy. Endoscopy plays an important role in the diagnosis and management of pancreatic cancer. Endoscopic ultrasound imaging (EUS) is the most sensitive modality for diagnosis, especially for small pancreatic tumors; it also allows tissue acquisition for histological diagnosis. Computed tomography scanning and EUS play complementary roles in staging and are comparable in determining resectability. Endoscopic retrograde cholangiopancreatography allows tissue sampling but is limited to palliative biliary drainage in most cases. In this article, we review the role of endoscopy in the diagnosis and management of pancreatic adenocarcinoma, with special emphasis on the use of endoscopic ultrasound and endoscopic retrograde cholangiopancreatography (ERCP).

Investigating the prognostic value of KOC (K homology domain containing protein overexpressed in cancer) overexpression after curative intent resection of pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic adenocarcinoma (PDAC) is now the third leading cause of cancer mortality in the United States. More than 80% of patients present with distant metastasis precluding surgical eligibility. Even among patients with localized disease deemed eligible for surgical resection, the median survival is only 22.8 months due to high recurrence rates. Identification of a biomarker correlated with patient specific prognosis upon initial diagnosis can serve as a way to individualize treatment options.

METHODS

We performed a retrospective cohort study analyzing pathology of patients who underwent curative intent surgery for PDAC at Geisinger Medical Center from 1998-2011 to identify whether the expression of KOC can be predictive of patient specific prognosis. Tissue microarrays of specimens were assessed by immunohistochemistry.

RESULTS

A total of 62 patients are included. Comparisons between groups on overall survival (OS) and progression free survival (PFS) are estimated using the Kaplan-Meier method and the log-rank test. Each biomarker was represented as low and high expression by categorizing the expression score at <4+ or >4+, based on intensity and extent of cells stained. 40 deaths occurred in the sample. Distant metastasis and differentiation (well/moderate vs. poor) were related to OS (P=0.0120, P=0.0086). Twenty-nine patients progressed in their disease. High/low KOC expression were significantly related to PFS (P=0.0556). Patients with a high KOC expression were more than 2 times more likely to progress compared to those with a low KOC expression (HR =2.04; 95% CI: 0.97, 4.29).

CONCLUSIONS

Our data is suggestive of KOC being a useful prognostic biomarker for identifying those patients with PDAC who have a high risk for early progression and distant metastasis. Larger studies are needed to determine whether KOC can be a therapeutic target in the treatment of pancreatic cancer. Furthermore, considering high KOC expressers had a worse PFS than their counterparts, investigation regarding the use of KOC expression as a biomarker to preselect patients who may benefit most from neoadjuvant chemotherapy is warranted.

RACK1 overexpression associates with pancreatic ductal adenocarcinoma growth and poor prognosis

OBJECTIVES

The receptor for activated protein kinase C (RACK1) is a scaffold protein involved in multiple intracellular signal pathways. Previous studies have shown that RACK1 is associated with the progression of multiple cancer types, including hepatocellular carcinoma and gastric cancer. However, the role of RACK1 in human pancreatic ductal adenocarcinoma (PDAC) remains unclear.

METHODS

In this study, the expression of RACK1 was evaluated by Western blot analysis in 8 paired fresh PDAC tissues and immunohistochemistry on 179 paraffin-embedded slices. Then, we used Fisher exact test to analyze the correlation between RACK1 expression and clinicopathological characteristics. Starvation and re-feeding assay was used to assess cell cycle. Western blot, CCK8, flow cytometry assays, and colony formation analyses demonstrated that RACK1 played an essential role in PDAC development. Annexin-V/PI apoptotic assay and western blot showed that RACK1 was involved in regulating the apoptosis of PDAC cells.

RESULTS

RACK1 was highly expressed in PDAC tissues and cell lines and was significantly associated with multiple clinicopathological factors. Univariate and multivariate analyses showed that high RACK1 expression was identified to be an independent prognostic factor for PDAC patients' survival. In vitro, serum starvation-refeeding experiment suggested that RACK1 was upregulated in proliferating PDAC cells, together with the percentage of cells at the S phase, and was correlated with the expression of Cyclin D1. Moreover, Overexpression of RACK1 facilitated the proliferation and cell cycle progression of PDAC cells, while downregulation of RACK1 induced growth impairment, G1/S cell cycle arrest and apoptosis in PDAC cells. Silencing RACK1 decreased bcl-2 expression, increased cleaved caspase3 expression level and induced the apoptosis of PDAC cells.

CONCLUSIONS

Our results suggest that RACK1 could play an important role in the tumorigenesis of PDAC and serve as a potential therapeutical target in PDAC treatment.

Stereotactic body radiotherapy for the pancreas: a critical review for the medical oncologist

With recent advances in imaging modalities and radiation therapy, stereotactic body radiotherapy (SBRT) has allowed for the delivery of high doses of radiation with accuracy and precision. As such, SBRT has generated favorable results in the treatment of several cancers. Although the role of radiation has been controversial for the treatment of pancreatic ductal adenocarcinoma (PDAC) due to rather lackluster results in clinical trials, SBRT may offer improved outcomes, enhance the quality of life, and aid in palliative care settings for PDAC patients. This review delineates the role of SBRT in the treatment of PDAC, presents the defining principles of radiation biology and the radiation oncology work flow, and discusses the prospects of new treatment regimens involving tumor immunology and radiation therapy.

Specific increase in serum core-fucosylated haptoglobin in patients with chronic pancreatitis

BACKGROUND/OBJECTIVES

Pancreatic ductal adenocarcinoma (PDAC) has the worst prognosis of all malignancies, and its diagnosis in early stages is the most important prognostic factor. Chronic pancreatitis (CP), a common background of PDAC occurrence, is morphologically defined as progressive pancreatic fibrosis and inflammation accompanied by pancreatic exocrine cell atrophy. We recently found that inflammation and fibrosis are independent characteristic histological changes in noncancerous lesions in PDAC patients despite the absence of a past history of clinical CP. Subclinical CP is an important background for PDAC occurrence. Therefore, there is an urgent need to develop a noninvasive and reliable biomarker for CP diagnosis.

METHODS

Fifty-nine healthy volunteers (HV), 159 patients with CP, and 83 patients with PDAC were enrolled in this study. We measured serum total fucosylated haptoglobin (Fuc-Hpt) and core-Fuc-Hpt levels using lectin-antibody enzyme-linked immunosorbent assay kits that we developed. In these kits, total Fuc-Hpt and core-Fuc-Hpt were measured using Aleuria aurantia lectin and Pholiota squarrosa lectin, respectively.

RESULTS

Serum Fuc-Hpt levels were significantly increased in CP patients compared to HV (P < 0.0001) and were further increased in PDAC patients (P < 0.0001). Interestingly, serum core-Fuc-Hpt levels were significantly higher in CP patients compared to HV (P < 0.0001) and PDAC patients (P < 0.0001). Multivariate analyses demonstrated that total serum core-Fuc-Hpt was an independent determinant for CP diagnosis, but Fuc-Hpt was not.

CONCLUSIONS

A dramatic change in oligosaccharides was observed in serum haptoglobin between CP and PDAC. Serum core-Fuc-Hpt may be a novel and useful biomarker for CP diagnosis.

EGFR-targeted gelatin nanoparticles for systemic administration of gemcitabine in an orthotopic pancreatic cancer model

In this study, we have formulated redox-responsive epidermal growth factor receptor (EGFR)-targeted type B gelatin nanoparticles as a targeted vector for systemic delivery of gemcitabine therapy in pancreatic cancer. The gelatin nanoparticles were formed by ethanol-induced desolvation process to encapsulate the bound drug. The surface of the nanoparticles was decorated either with poly(ethylene glycol) (PEG) chains to impart enhanced circulation time or with EGFR targeting peptide to confer target specificity. Our in vitro studies in Panc-1 human pancreatic ductal adenocarcinoma cells confirm that gemcitabine encapsulated in EGFR-targeted gelatin nanoparticles, released through disulfide bond cleavage, had a significantly improved cytotoxic profile. Further, the in vivo anticancer activity was evaluated in an orthotopic pancreatic adenocarcinoma tumor bearing SCID beige mice, which confirmed that EGFR-targeted gelatin nanoparticles could efficiently deliver gemcitabine to the tumor leading to higher therapeutic benefit as compared to the drug in solution.

FROM THE CLINICAL EDITOR

The treatment of pancreatic cancer remains unsatisfactory, with an average 5-year survival of less than 5%. New treatment modalities are thus urgently needed. In this study, the authors presented their formulation of redox-responsive epidermal growth factor receptor (EGFR)-targeted type B gelatin nanoparticles as a carrier for gemcitabine. In-vitro and in-vivo experiments showed encouraging results. It is hoped that the findings would provide a novel and alternative drug delivery platform for the future.

Combining conventional and stroma-derived tumour markers in pancreatic ductal adenocarcinoma

BACKGROUND

A lack of disease-specific symptoms and good tumour markers makes early detection and diagnosis of pancreatic ductal adenocarcinoma (PDAC) challenging.

OBJECTIVE

To analyse the tissue expression and circulating levels of four stroma-derived substances (type IV collagen, endostatin/type XVIII collagen, osteopontin and tenascin C) and four conventional tumour markers (CA 19-9, TPS, CEA and Ca 125) in a PDAC cohort.

METHODS

Tissue expression of markers in normal pancreas and PDAC tissue was analysed with immunofluorescence. Plasma concentrations of markers were measured before and after surgery. Patients with non-malignant disorders served as controls.

RESULTS

The conventional and stromal substances were expressed in the cancer cell compartment and the stroma, respectively. Although most patients had increased levels of many markers before surgery, 2/12 (17%) of patients had normal levels of Ca 19-9 at this stage. High preoperative endostatin/type XVIII collagen, and postoperative type IV collagen was associated with short survival. Neither the pre- nor postoperative levels of TPS, Ca 125 or CA 19-9 were associated to survival.

CONCLUSIONS

PDAC is characterized by an abundant stroma. These initial observations indicate that the stroma can be a source of PDAC tumour markers that are found in different compartments of the cancer, thus reflecting different aspects of tumour biology.

NF45 overexpression is associated with poor prognosis and enhanced cell proliferation of pancreatic ductal adenocarcinoma

NF45, also referred to as nuclear factor of activated T cells, has been reported to promote the progression of multiple cancer types. However, the expression and physiological significance of NF45 in pancreatic ductal adenocarcinoma (PDAC) remain largely elusive. In this study, we investigated the clinical relevance and potential role of NF45 expression in PDAC development. Western blot analysis revealed that NF45 was remarkably upregulated in PDAC tissues, compared with the adjacent non-tumorous ones. In addition, the expression of NF45 in 122 patients with PDAC was evaluated using immunohistochemistry. In this way, we found that NF45 was abundantly expressed in PDAC tissues, and the expression of NF45 was correlated with tumor size (p = 0.007), histological differentiation (p = 0.033), and TNM stage (p = 0.001). Importantly, patients with low levels of NF45 expression exhibited better postoperative prognosis as compared with those with high NF45 expression. Furthermore, using PDAC cell cultures, we found that interference of NF45 expression using siRNA oligos suppressed PDAC cell proliferation and retarded cell cycle progression. Moreover, depletion of NF45 impaired the levels of cellular cyclin E and proliferating cell nuclear antigen (PCNA). Conversely, overexpression of NF45 facilitated the cell growth and accelerated cell cycle progression. Our results establish NF45 as an important indicator of PDAC prognosis with potential utility as a therapeutic target in this lethal disease.

Elevated miR-483-3p expression is an early event and indicates poor prognosis in pancreatic ductal adenocarcinoma

MiR-483-3p has been reported to be widely involved in diverse human malignancies. However, the exact role of miR-483-3p remains elusive in pancreatic ductal adenocarcinoma (PDAC). The objective of this study is to determine the expression pattern and clinical implications of miR-483-3p in PDAC. MiR-483-3p levels were evaluated by locked nucleic acid-in situ hybridization (LNA-ISH) in a tissue microarray including 63 PDAC tumors and 10 normal pancreatic tissues, followed by evaluation in an independent set of 117 pairs of matched PDAC tumors and adjacent tumor-free pancreatic tissues. Expression of miR-483-3p was further evaluated in pancreatic intra-epithelial neoplasias (PanINs) and chronic pancreatitis (CP). The impact of miR-483-3p on cell proliferation, growth, and anchorage-independent colony formation was also assessed in vitro and in vivo. Microarray analysis revealed that miR-483-3p was positively stained in 61 (96.8 %) PDAC samples, but not detectable in normal pancreatic duct tissue. In the 117 PDAC samples, 100 % were miR-483-3p positive, with 55.6 % (65/117) strongly positive, compared to only 13.7 % (16/117) weakly positive in adjacent normal pancreatic duct tissues. MiR-483-3p expression was associated with tumor grading (p < 0.05) and was an independent predictor of poor overall survival in multivariate analysis (HR = 2.584; 95 % CI = 1.268-5.264). Moreover, from PanIN1 to PanIN3, the rate of strong miR-483-3p-positive staining was 0 % (0/39), 14.8 % (4/27), and 87.5 % (14/16), respectively. Six (54.5 %) CP samples were only weakly stained for miR-483-3p. Inhibition of miR-483-3p suppressed cell proliferation, growth, and colony formation in vitro and decreased tumor cell growth in nude mouse xenografts in vivo. These results suggest that aberrant miR-483-3p expression is an early event in PDAC tumorigenesis and is associated with tumor differentiation and prognosis. It also may be a potential target for PDAC molecular therapeutics.

High expression of ErbB3 binding protein 1 (EBP1) predicts poor prognosis of pancreatic ductal adenocarcinoma (PDAC)

Recent studies have identified that ErbB3 binding protein 1 (EBP1) is broadly expressed in various cancer tissues and critically involved in plenty of biological processes in this regard. However, the functional role of EBP1 in pancreatic ductal adenocarcinoma (PDAC) has never been elucidated. In this study, we found that EBP1 could serve as a prognostic biomarker of PDAC. Western blot analysis revealed that EBP1 was remarkably upregulated in PDAC tissues and cell lines. Using immunohistochemical analysis, we showed that the expression of EBP1 was correlated with tumor size (P = 0.004), histological differentiation (P = 0.041), and tumor node metastasis (TNM) stage (P = 0.000). Notably, Kaplan-Meier curve showed that high expression of EBP1 predicted significantly worsened prognosis of PDAC patients (P = 0.001). In addition, knockdown of EBP1 expression suppressed PDAC cell proliferation and retarded cell cycle progression. Furthermore, depletion of EBP1 induced the apoptosis of Panc-1 cells. Of great interest, we found that EBP1 interacted with anti-apoptotic protein, Bcl-xL, and promoted its accumulation. In summary, our results suggest that EBP1 is a novel prognostic indicator and potential therapeutic target of PDAC, shedding new insights into the important role of EBP1 in cancer development.

Transforming growth factor β receptor signaling restrains growth of pancreatic carcinoma cells

Pancreatic ductal adenocarcinoma (PDAC) is extremely malignant. Efficient control of cancer growth may substantially improve the survival of PDAC patients. However, no efficient treatments are so far available. Here, we inhibited transforming growth factor β (TGFβ) receptor signaling by overexpression of a key inhibitor of this pathway, SMAD7, in the mouse pancreas, using a recently developed intraductal infusion method. Overexpression of SMAD7 significantly increased growth of both implanted PDAC and PDAC by K-ras modification. Our data thus suggest that TGFβ receptor signaling restrains growth of PDAC, and modulation of TGFβ receptor signaling may be an effective treatment for PDAC.

miR-211 modulates gemcitabine activity through downregulation of ribonucleotide reductase and inhibits the invasive behavior of pancreatic cancer cells

Only a subset of radically-resected pancreatic ductal adenocarcinoma (PDAC) patients benefit from gemcitabine-based chemotherapy, thus the identification of novel prognostic factors is essential. In a high-throughput, microRNA (miRNA) array, miR-211 emerged as the best discriminating miRNA, with high expression associated with long survival. Here, we further explored the biological role of miRNA-211 in gemcitabine activity in the human PDAC cells (SUIT-2) subclones SUIT2-007 and SUIT2-028. Our results showed that miR-211 was expressed differentially in PDAC cells characterized by differential metastatic capability. In particular, S2-028 with lower metastatic ability had a higher expression of miR-211, compared to the S2-007 with higher metastatic capacity. Enforced expression of miR-211 via pre-miR-211 significantly reduced cell migration and invasion (e.g., 40% reduction of invasion of SUIT2 cells, compared to control; p<.05). Moreover, we demonstrated that induction of the miR-211 expression in the cells increased the sensitivity to gemcitabine and reduced the expression of its target ribonucleotide reductase subunit 2 (RRM2). In conclusion, miR-211 functional analyses suggested the role of RRM2 as a target of miR-211 in the modulation of gemcitabine sensitivity. Moreover, inhibition of cell migration and invasion might explain the less aggressive behavior of pancreatic cancer cells with higher expression levels of miR-211.

Abnormal distribution of peripheral lymphocyte subsets induced by PDAC modulates overall survival

BACKGROUND/OBJECTIVES

The impairment of the immune system is prevalent in patients with malignancies, including pancreatic ductal adenocarcinoma (PDAC). The present study aimed to evaluate alternations of peripheral lymphocyte subsets in patients with PDAC, and also to assess the prognostic value of observed changes.

METHODS

We recruited 160 consecutive PDAC patients who had undergone radical surgical resection between 2010 and 2013. To investigate the prognostic factors, we detected the peripheral lymphocyte subsets in PDAC by flow cytometry, including T cells (CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD8(+)CD28(+)), regulatory T cells (Tregs, CD4(+)CD25(+)CD127(-)), natural killer cells (NK cells, CD3(-)CD56(+)) and B cells (CD19(+)). We also evaluated the clinical and pathological features of these patients. Survival analysis was performed by univariate and multivariate analyses.

RESULTS

Our results indicated the profile of peripheral lymphocyte subsets undergone profound changes in PDAC patients. Univariate and multivariate analysis indicated the levels of peripheral lymphocyte subsets (CD19(+) B cells, Tregs and CD8(+)CD28(+) T cells) were independent predictors for overall survival. The results also suggested that the systemic impairment of immune system in patients with PDAC, was reversed when primary tumor was removed.

CONCLUSIONS

The present study provided some evidences that the impairment of host immunity induced by PDAC may play a role in the survival of patients.

Ring-enhancement pattern on contrast-enhanced CT predicts adenosquamous carcinoma of the pancreas: a matched case-control study

OBJECTIVES

Adenosquamous carcinoma of the pancreas (ASC) is a rare malignant neoplasm of the pancreas, exhibiting both glandular and squamous differentiation. However, little is known about its imaging features. This study examined the imaging features of pancreatic ASC.

METHODS

We evaluated images of contrast-enhanced computed tomography (CT) and endoscopic ultrasonography (EUS). As controls, solid pancreatic neoplasms matched in a 2:1 ratio to ASC cases for age, sex and tumor location were also evaluated.

RESULTS

Twenty-three ASC cases were examined, and 46 solid pancreatic neoplasms (43 pancreatic ductal adenocarcinomas, two pancreatic neuroendocrine tumors and one acinar cell carcinoma) were matched as controls. Univariate analysis demonstrated significant differences in the outline and vascularity of tumors on contrast-enhanced CT in the ASC and control groups (P < 0.001 and P < 0.001, respectively). A smooth outline, cystic changes, and the ring-enhancement pattern on contrast-enhanced CT were seen to have significant predictive powers by stepwise forward logistic regression analysis (P = 0.044, P = 0.010, and P = 0.001, respectively). Of the three, the ring-enhancement pattern was the most useful, and its predictive diagnostic sensitivity, specificity, positive predictive value and negative predictive value for diagnosis of ASC were 65.2%, 89.6%, 75.0% and 84.3%, respectively.

CONCLUSIONS

These results demonstrate that presence of the ring-enhancement pattern on contrast-enhanced CT is the most useful predictive factor for ASC.