Management options in locally advanced pancreatic cancer

Preclinical evaluation of pentagamavunone-1 as monotherapy and combination therapy for pancreatic cancer in multiple xenograft models

We previously reported that pentagamavunone-1 (PGV-1) effectively inhibited cell proliferation in many types of human tumors, including pancreatic cancer, by inducing M phase (prometaphase) arrest, senescence, and apoptosis with few side effects. However, a detailed evaluation of the effects of PGV-1 on pancreatic cancer cells in an in vivo setting has not yet been conducted. The present study investigated the potential efficacy of PGV-1 as both monotherapy and combination therapy for pancreatic cancer using multiple xenograft mouse assays. A cell-line derived xenograft model (CDX-M) with pancreatic cancer cell line and a patient-derived xenograft mouse model (PDX-M) using resected pancreatic cancer samples without neoadjuvant chemotherapy were established in both heterotopic and orthotopic manners. PGV-1 effectively suppressed tumor formation at the heterotopic and orthotopic sites in CDX-M than in untreated mice. Combination therapy with PGV-1 and gemcitabine more effectively suppressed tumor formation than monotherapy with PGV-1 or gemcitabine when administered after tumor formation. Monotherapy with PGV-1 or gemcitabine less effectively suppressed tumor formation in PDX-M than in CDX-M, whereas combination therapy with PGV-1 and gemcitabine more effectively suppressed tumor formation. PGV-1 as monotherapy and combination therapy with gemcitabine effectively inhibited tumor formation and has potential as an anticancer candidate for pancreatic cancer.

Impact of osteopenia on surgical and oncological outcomes in patients with pancreatic cancer

INTRODUCTION

Osteopenia, which is defined as a decrease in bone mineral density, has been recently recognized as a metabolic and an oncological biomarker for surgery in patients with malignancy. We aimed to study the prognostic impact of osteopenia in patients with pancreatic cancer (PC) after resection.

METHODS

A total of 56 patients who underwent curative resection of PC were retrospectively investigated. The skeletal muscle index at the third lumbar spine and bone mineral density at the 11th thoracic vertebra were measured using computed tomography.

RESULTS

Sarcopenia and osteopenia were identified in 24 (43%) and 27 (48%) patients, respectively. The overall and disease-free survival rates were significantly lower in the sarcopenia group than in the non-sarcopenia group (p < 0.01 and p < 0.01, respectively) and in the osteopenia group than in the non-osteopenia group (p < 0.01 and p < 0.01, respectively). In multivariate analysis, sarcopenia (odds ratio [OR] 4.05; 95% confidence interval [CI] 1.23-13.38; p = 0.02) was a significant independent predictor of 1-year disease-free survival. Further, sarcopenia (OR 6.00; 95% CI 1.46-24.6; p = 0.01) and osteopenia (OR 4.66; 95% CI 1.15-18.82; p = 0.03) were significant independent predictors of 2-year overall survival.

CONCLUSION

Osteopenia is a significant negative factor for 2-year overall survival after curative resection of PC.

Sarcopenia: looking to muscle mass to better manage pancreatic cancer patients

PURPOSE OF REVIEW

Overall survival of patients with pancreatic cancer is strongly conditioned by tumor biology and the incidence of malnutrition and metabolic disorders. In this landscape, the assessment of body composition is crucial to properly manage the clinical implications of muscle wasting. The pathogenesis of this condition is the result of a complex interplay between cancer and the host. In particular, sarcopenia is induced by an inadequate nutritional intake, hormonal abnormalities, inflammation and imbalance between anabolic and catabolic pathways.

RECENT FINDINGS

Recent evidences have highlighted the role of sarcopenia in cancer patients, revealing a prognostic impact on morbidity, mortality and survival.

SUMMARY

The occurrence of sarcopenia could amplify chemotherapy-induced toxicities, prolong hospitalizations and reduce adherence to anticancer treatment, worsening quality of life and survival. Although considerable efforts have been made to develop treatment strategies, no effective interventions have been identified so far. Nevertheless, if promptly and adequately supported, pancreatic cancer might benefit from adopted dietary intervention to avoid further loss of lean mass.

Shear Wave Elastography Can Differentiate between Radiation-Responsive and Non-responsive Pancreatic Tumors: An ex Vivo Study with Murine Models

Neither contrast-enhanced computed tomography nor magnetic resonance imaging can monitor changes in the pancreatic ductal adenocarcinoma microenvironment during therapy. We hypothesized that shear wave elastography could overcome this limitation. To test this hypothesis, we measured the shear modulus of two groups of murine pancreatic tumors (KCKO, n = 30; PAN02, n = 30) treated with stereotactic body radiation therapy (SBRT). The mean shear modulus of KCKO tumors was 7.651 kPa higher than that of PAN02 tumors (p < 0.001). SBRT reduced the shear modulus in KCKO tumors by 8.914 kPa (p < 0.001). No significant difference in the shear modulus of SBRT-treated PAN02 tumors was observed. Additionally, necrotic and collagen densities were reduced only in the SBRT-treated KCKO tumors. Shear modulus was dependent on collagen distribution and histological texture parameters (i.e., entropy and fractional dimension). Shear wave elastography imaging differentiates between SBRT-responsive (KCKO) and non-responsive (PAN02) tumors.

NETO2 promotes pancreatic cancer cell proliferation, invasion and migration via activation of the STAT3 signaling pathway

Purpose: The biological functions of neuropilin and tolloid-like 2 (NETO2) in the progression of pancreatic cancer remained unexplored. We aimed to investigate the biological roles and underlying molecular mechanisms of NETO2 in pancreatic cancer.

Materials and methods: Thirty paired pancreatic tumor tissue samples and corresponding nontumor tissues were obtained from 30 pancreatic cancer patients who did not receive preoperative chemotherapy or radiotherapy. The changes in multiple cellular functions associated with tumor progression were assessed after NETO2 knockdown/overexpression in pancreatic cancer cell lines. Additionally, a mouse-xenograft model was developed to verify the in vitro results.

Results:NETO2 was upregulated in pancreatic tumor tissues. Elevated expression of NETO2 was not only associated with an advanced tumor stage, but was also a prediction of poor prognosis for pancreatic cancer patients. Knockdown of NETO2 in pancreatic cancer cell lines arrested the cell cycle and inhibited cell proliferation, colony formation, invasion, and migration; in contrast, overexpression of NETO2 had an opposite effect on all of these parameters. A STAT3 specific inhibitor, cryptotanshinone, reversed the tumor-promoting effects induced by NETO2 overexpression in pancreatic cancer. Western blot analysis showed that invasion and migration were closely related to epithelial–mesenchymal transition, and that the STAT3 signaling pathway was involved in NETO2-mediated oncogenic transformation in pancreatic cancer cells. Furthermore, NETO2 knockdown significantly inhibited the growth of pancreatic tumor xenografts in nude mice.

Conclusion:NETO2 has an important role in the progression and metastasis of pancreatic cancer and could serve as a novel candidate for targeted therapy of pancreatic cancer.

Combined morphologic and metabolic pipeline for Positron emission tomography/computed tomography based radiotherapy response evaluation in locally advanced pancreatic adenocarcinoma

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A novel morphologic and metabolic combined pipeline for PA response evaluation.

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The derived metric outperformed traditional imaging metrics in risk stratification.

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May serve as a new image biomarker to characterize heterogeneous tumor response.

Background and purpose

Adaptive radiation planning for pancreatic adenocarcinoma (PA) relies on accurate treatment response assessment, while traditional response evaluation criteria inefficiently characterize tumors with complex morphological features or intrinsically low metabolism. To better assess treatment response of PA, we quantify and compare regional morphological and metabolic features of the 3D pre- and post-radiation therapy (RT) tumor models.

Materials and methods

Thirty-one PA patients with pre and post-RT Positron emission tomography/computed tomography (PET/CT) scans were evaluated. 3D meshes of pre- and post-RT tumors were generated and registered to establish vertex-wise correspondence. To assess tumor response, Mahalanobis distances (M_dist|_Fusion) between pre- and post-RT tumor surfaces with anatomic and metabolic fused vectors were calculated for each patient. M_dist|_Fusion was evaluated by overall survival (OS) prediction and survival risk classification. As a comparison, the same analyses were conducted on traditional imaging/physiological predictors, and distances measurements based on metabolic and morphological features only.

Results

Among all the imaging/physiological parameters, M_dist|_Fusion was shown to be the best predictor of OS (HR = 0.52, p = 0.008), while other parameters failed to reach significance. Moreover, M_dist|_Fusion outperformed traditional morphologic and metabolic measurements in patient risk stratification, either alone (HR = 11.51, p < 0.001) or combined with age (HR = 9.04, p < 0.001).

Conclusions

We introduced a PET/CT-based novel morphologic and metabolic pipeline for response evaluation in locally advanced PA. The fused M_dist|_Fusion outperformed traditional morphologic, metabolic, and physiological measurements in OS prediction and risk stratification. The novel fusion model may serve as a new imaging-marker to more accurately characterize the heterogeneous tumor RT response.

Novel 4D-MRI of tumor infiltrating vasculature: characterizing tumor and vessel volume motion for selective boost volume definition in pancreatic radiotherapy

BACKGROUND

Pancreatic ductal adenocarcinoma has dismal prognosis. Most patients receive radiation therapy (RT), which is complicated by respiration induced organ motion in upper abdomen. The purpose of this study is to report our early clinical experience in a novel self-gated k-space sorted four-dimensional magnetic resonance imaging (4D-MRI) with slab-selective (SS) excitation to highlight tumor infiltrating blood vessels for pancreatic RT.

METHODS

Ten consecutive patients with borderline resectable or locally advanced pancreatic cancer were recruited to the study. Non-contrast 4D-MRI with and without slab-selective excitation and 4D-CT with delay contrast were performed on all patients. Vessel-tissue CNR were calculated for aorta and critical vessels (superior mesenteric artery or superior mesenteric vein) encompassed by tumor. Respiratory motion trajectories for tumor, as well as involved vessels were analyzed on SS-4D-MRI. Intra-class cross correlation (ICC) between tumor volume and involved vessels were calculated.

RESULTS

Among all 4D imaging modalities evaluated, SS-4D-MRI sampling trajectory results in images with highest vessel-tissue CNR comparing to non-slab-selective 4D-MRI and 4D-CT for all patients studied. Average (±standard deviation) CNR for involved vessels are 13.1 ± 8.4 and 3.2 ± 2.7 for SS-4D-MRI and 4D-CT, respectively. The ICC factors comparing tumor and involved vessels motion trajectories are 0.93 ± 0.10, 0.65 ± 0.31 and 0.77 ± 0.23 for superior-inferior, anterior-posterior and medial-lateral directions respectively.

CONCLUSIONS

A novel 4D-MRI sequence based on 3D-radial sampling and slab-selective excitation has been assessed for pancreatic cancer patients. The non-contrast 4D-MRI images showed significantly better contrast to noise ratio for the vessels that limit tumor resectability compared to 4D-CT with delayed contrast. The sequence has great potential in accurately defining both the tumor and boost volume margins for pancreas RT with simultaneous integrated boost.

Skeletal Muscle Fibrosis in Pancreatic Cancer Patients with Respect to Survival

Background

Cancer cachexia is a catabolic condition characterized by skeletal muscle wasting, consequent to tumor burden, which negatively impacts tolerance to cancer therapies and contributes to increased mortality. Partly because of the limited knowledge of the underlying mechanisms of cancer cachexia derived from human studies, however, the ability to therapeutically intervene remains elusive. The purpose of the current study was therefore to better define the phenotype of skeletal muscle obtained from patients with pancreatic ductal adenocarcinoma (PDAC), which has one of the highest rates of cachexia.

Methods

Morphological analyses were performed on rectus abdominis muscle biopsies obtained from resectable PDAC patients undergoing tumor resection surgery (N = 20) and from weight-stable non-cancer control subjects undergoing benign abdominal surgery (N = 16). PDAC patients with a body weight loss of greater than 5% during the previous 6 months were considered cachectic (N = 15). Statistical tests were two sided.

Results

Skeletal muscle from cachectic PDAC patients had increased collagen content compared with non-cancer control subjects (1.43% vs 9.66%, P = .0004, Dunn test). Across all PDAC patients, collagen content positively correlated with body weight loss (P = .0016, r = 0.672), was increased in patients with lymph node metastasis (P = .007, Mann-Whitney U test), and was associated with survival on univariate (HR = 1.08, 95% confidence interval [CI] = 1.02 to 1.04, P = .008) and multivariable analyses (HR = 1.08, 95% CI = 1.00 to 1.17, P = .038). Cachectic PDAC patients also displayed increased lipid deposition (2.63% vs 5.72%, P = .042), infiltration of CD68+ macrophages (63.6 cells/mm² vs 233.8 cells/mm², P = .0238), calcium deposition (0.21% vs 2.51%, P = .030), and evidence of deficient cellular quality control mechanisms (Mann-Whitney U test). Transcriptional profiling of all patients supported these findings by identifying gene clusters related to wounding, inflammation, and cellular response to TGF-β upregulated in cachectic PDAC patients compared with non-cancer control subjects.

Conclusions

To our knowledge, this work is the first to demonstrate increased collagen content in cachectic PDAC patients that is associated with poor survival.

Cordycepin induces apoptosis in human pancreatic cancer cells via the mitochondrial-mediated intrinsic pathway and suppresses tumor growth in vivo

Background

Cordycepin, the main active ingredient of a traditional Chinese herbal remedy - extracted from Cordyceps sinensis - has been demonstrated as a very effective anti-inflammatory and antitumor drug. The present study investigated its antitumor effect on pancreatic cancer, a highly aggressive cancer with extremely poor prognosis due to malignancy, and clarified its underlying mechanism both in vitro and in vivo.

Methods

The antitumor viability of cordycepin on human pancreatic cancer MIAPaCa-2 and Capan-1 cells was determined by colony formation assays. Annexin V/PI double staining and flow cytometry assay were used to investigate whether cordycepin induced apoptosis and cell cycle arrest. The mitochondrial membrane potential (ΔΨm) was analyzed by Rhodamine 123 staining, and expression of related proteins evaluated by Western blot and immunohistochemistry, both on pancreatic cancer cells and tumor xenografts to reveal the potential mechanism for the effect of cordycepin. Furthermore, the in vivo efficacy was examined on nude mice bearing MIAPaCa-2 cell tumors treated by intraperitoneal injection of cordycepin (0, 15, and 50 mg/kg/d) for 28 days.

Results

Cordycepin inhibited cell viability, proliferation and colony formation ability and induced cell cycle arrest and early apoptosis of human pancreatic cancer cells (MIAPaCa-2 and Capan-1) in a dose- and time-dependent manner. The same effect was also observed in vivo. Decrease of ΔΨm and upregulation of Bax, cleaved caspase-3, cleaved caspase-9, and cleaved PARP as well as downregulation of Bcl-2 both in vitro and in vivo indicated that the mitochondria-mediated intrinsic pathway was involved in cordycepin's antitumor effect.

Conclusion

Our data showed that cordycepin inhibited the activity of pancreatic cancer both in vitro and in vivo by regulating apoptosis-related protein expression through the mitochondrial pathway and suggest that cordycepin may be a promising therapeutic option for pancreatic cancer.

Improving prediction of surgical resectability over current staging guidelines in patients with pancreatic cancer who receive stereotactic body radiation therapy

Purpose

For patients with localized pancreatic cancer (PC) with vascular involvement, prediction of resectability is critical to define optimal treatment. However, the current definitions of borderline resectable (BR) and locally advanced (LA) disease leave considerable heterogeneity in outcomes within these classifications. Moreover, factors beyond vascular involvement likely affect the ability to undergo resection. Herein, we share our experience developing a model that incorporates detailed radiologic, patient, and treatment factors to predict surgical resectability in patients with BR and LA PC who undergo stereotactic body radiation therapy (SBRT).

Methods and materials

Patients with BR or LA PC who were treated with SBRT between 2010 and 2016 were included. The primary endpoint was margin negative resection, and predictors included age, sex, race, treatment year, performance status, initial staging, tumor volume and location, baseline and pre-SBRT carbohydrate antigen 19-9 levels, chemotherapy regimen and duration, and radiation dose. In addition, we characterized the relationship between tumors and key arteries (superior mesenteric, celiac, and common hepatic arteries), using overlap volume histograms derived from computed tomography data. A classification and regression tree was built, and leave-one-out cross-validation was performed. Prediction of surgical resection was compared between our model and staging in accordance with the National Comprehensive Care Network guidelines using McNemar's test.

Results

A total of 191 patients were identified (128 patients with LA and 63 with BR), of which 87 patients (46%) underwent margin negative resection. The median total dose was 33 Gy. Predictors included the chemotherapy regimen, amount of arterial involvement, and age. Importantly, radiation dose that covers 95% of gross tumor volume (GTV D95), was a key predictor of resectability in certain subpopulations, and the model showed improved accuracy in the prediction of margin negative resection compared with National Comprehensive Care Network guideline staging (75% vs 63%; P < .05).

Conclusions

We demonstrate the ability to improve prediction of surgical resectabiliy beyond the current staging guidelines, which highlights the value of assessing vascular involvement in a continuous manner. In addition, we show an association between radiation dose and resectability, which suggests the potential importance of radiation to allow for resection in certain populations. External data are needed for validation and to increase the robustness of the model.

Indications and Perioperative Outcomes for Pancreatectomy with Arterial Resection

BACKGROUND

Pancreatectomy with arterial resection (AR) is performed infrequently. As indications evolve, we evaluated indications, outcomes, and predictors of mortality, morbidity, and survival after AR.

STUDY DESIGN

We performed a single-institution review of elective pancreatectomies with AR (from July1990 to July 2017). Univariate and multivariate analyses were performed for predictors of outcomes and survival.

RESULTS

A total of 111 patients underwent pancreatectomy with AR including any hepatic (54%), any celiac (44%), any superior mesenteric (14%), or multiple ARs (14%), with revascularization in 55%. The majority of cases were planned (77%) and performed post-2010 (78%). Overall 90-day major morbidity (≥grade III) and mortality were 54% and 13%, respectively, due to post-pancreatectomy hemorrhage (PPH), postoperative pancreatic fistula (POPF), or ischemia in the majority of cases. There was a significant decrease in mortality post-2010 (9% vs 29%, p = 0.02), and this was protective on multivariate analysis (odds ratio [OR] 0.1, p = 0.004); PPH increased mortality (OR 6.1, p < 0.001). Post-pancreatectomy hemorrhage was associated with major morbidity (OR 5.1, p = 0.005), reoperation (OR = 23.0, p = 0.004), ICU (OR 5.5, p < 0.001), and readmission (OR 2.6, p = 0.004). Other morbidity predictors were AR with graft (OR 4.0, p = 0.031) and POPF (OR 3.1, p = 0.003). Median survival was 28.5 months and improved for ductal adenocarcinoma after neoadjuvant chemotherapy (p = 0.038). There were no differences in survival based on AR type.

CONCLUSIONS

Regardless of indication or type, pancreatectomy with AR is associated with risks greater than standard resections. Mortality has decreased in the modern era; however, morbidity remains high from hemorrhagic, fistula, or ischemia-related complications. Mitigation measures are needed if advanced resections are considered with increasing frequency given the potential oncologic benefit of AR in selected cases after modern chemotherapy.

Mesenchymal stem cells promote pancreatic adenocarcinoma cells invasion by transforming growth factor-β1 induced epithelial-mesenchymal transition

Mesenchymal stem cells (MSCs) could be ideal delivery vehicles for antitumor biological agents in pancreatic adenocarcinoma (PA). While the role of MSCs in tumor growth is elusive. Inflammation is an important feature of PA. In this study, we reported that MSCs pre-stimulated with the combination of TNF-α and IFN-γ promote PA cells invasion. The invasion of PA cell lines were evaluate by wound healing assay and transwell assay in vitro and liver metastasis in nude mice. We observed MSCs pre-stimulated with the combination of TNF-α and IFN-γ promoted PA cells invasion in vitro and in vivo. Consistent with MSCs promoting PA cells invasion, PA cells were found undergo epithelial-mesenchymal transition (EMT). We demonstrated that MSCs pre-stimulated with both of TNF-α and IFN-γ provoked expression transforming growth factor-β1 (TGF-β1). MSCs promoting EMT-mediated PA cells invasion could be reversed by short interfering RNA of TGF-β1. Our results suggest that MSCs could promote PA cells invasion in inflammation microenvironment and should be cautious as delivery vehicles in molecular target therapy.

Improved vessel-tissue contrast and image quality in 3D radial sampling-based 4D-MRI

Purpose

In radiation treatment planning for thoracic and abdominal tumors, 4D‐MRI has shown promise in respiratory motion characterization with improved soft‐tissue contrast compared to clinical standard, 4D computed tomography (4D‐CT). This study aimed to further improve vessel–tissue contrast and overall image quality in 3D radial sampling‐based 4D‐MRI using a slab‐selective (SS) excitation approach.

Methods

The technique was implemented in a 3D radial sampling with self‐gating‐based k‐space sorting sequence. The SS excitation approach was compared to a non‐selective (NS) approach in six cancer patients and two healthy volunteers at 3T. Improvements in vessel–tissue contrast ratio (CR) and vessel signal‐to‐noise ratio (SNR) were analyzed in five of the eight subjects. Image quality was visually assessed in all subjects on a 4‐point scale (0: poor; 3: excellent). Tumor (patients) and pancreas (healthy) motion trajectories were compared between the two imaging approaches.

Results

Compared with NS‐4D‐MRI, SS‐4D‐MRI significantly improved the overall vessel–tissue CR (2.60 ± 3.97 vs. 1.03 ± 1.44, P < 0.05), SNR (63.33 ± 38.45 vs. 35.74 ± 28.59, P < 0.05), and image quality score (2.6 ± 0.5 vs. 1.4 ± 0.5, P = 0.02). Motion trajectories from the two approaches exhibited strong correlation in the superior–inferior (0.96 ± 0.06), but weaker in the anterior–posterior (0.78 ± 0.24) and medial–lateral directions (0.46 ± 0.44).

Conclusions

The proposed 4D‐MRI with slab‐selectively excited 3D radial sampling allows for improved blood SNR, vessel–tissue CR, and image quality.

TGF-β in pancreatic cancer initiation and progression: two sides of the same coin

Pancreatic cancer is highly lethal malignant tumor with characterised rapid progression, invasiveness and resistance to radiochemotherapy. Transforming growth factor-β (TGF-β) signaling plays a dual role in both pro-tumorigenic and tumor suppressive of pancreatic cancer, depending on tumor stage and microenvironment. TGF-β signaling components alteration are common in pancreatic cancer, and its leading role in tumor formation and metastases has received increased attention. Many therapies have investigated to target TGF-β signaling in the preclinical and clinical setting. In this review, we highlight the dual roles of TGF-β and touch upon the perspectives on therapeutic target of TGF-β signaling in pancreatic cancer.

Neoadjuvant therapy in pancreatic cancer: a systematic review and meta-analysis of prospective studies

There is a strong rationale and many theoretical advantages for neoadjuvant therapy in pancreatic cancer (PC). However, study results have varied significantly. In this study, a systematic review and meta‐analysis of prospective studies were performed in order to evaluate safety and effectiveness of neoadjuvant therapy in PC. Thirty‐nine studies were selected (n = 1458 patients), with 14 studies focusing on patients with resectable disease (group 1), and 19 studies focusing on patients with borderline resectable and locally advanced disease (group 2). Neoadjuvant chemotherapy was administered in 97.4% of the studies, in which 76.9% was given radiotherapy and 74.4% administered with chemoradiation. The complete and partial response rate was 3.8% and 20.9%. The incidence of grade 3/4 toxicity was 11.3%. The overall resection rate after neoadjuvant therapy was 57.7% (group 1: 73.0%, group 2: 40.2%). The R0 resection rate was 84.2% (group 1: 88.2%, group 2: 79.4%). The overall survival for all patients was 16.79 months (resected 24.24, unresected 9.81; group 1: 17.76, group 2: 16.20). Our results demonstrate that neoadjuvant therapy has not been proven to be beneficial and should be considered with caution in patients with resectable PC. Patients with borderline resectable or locally advanced disease may benefit from neoadjuvant therapy, but further research is needed.

Identifying prognostic intratumor heterogeneity using pre- and post-radiotherapy 18F-FDG PET images for pancreatic cancer patients

BACKGROUND

To stratify risks of pancreatic adenocarcinoma (PA) patients using pre- and post-radiotherapy (RT) PET/CT images, and to assess the prognostic value of texture variations in predicting therapy response of patients.

METHODS

Twenty-six PA patients treated with RT from 2011-2013 with pre- and post-treatment 18F-FDG-PET/CT scans were identified. Tumor locoregional texture was calculated using 3D kernel-based approach, and texture variations were identified by fitting discrepancies of texture maps of pre- and post-treatment images. A total of 48 texture and clinical variables were identified and evaluated for association with overall survival (OS). The prognostic heterogeneity features were selected using lasso/elastic net regression, and further were evaluated by multivariate Cox analysis.

RESULTS

Median age was 69 y (range, 46-86 y). The texture map and temporal variations between pre- and post-treatment were well characterized by histograms and statistical fitting. The lasso analysis identified seven predictors (age, node stage, post-RT SUVmax, variations of homogeneity, variance, sum mean, and cluster tendency). The multivariate Cox analysis identified five significant variables: age, node stage, variations of homogeneity, variance, and cluster tendency (with P=0.020, 0.040, 0.065, 0.078, and 0.081, respectively). The patients were stratified into two groups based on the risk score of multivariate analysis with log-rank P=0.001: a low risk group (n=11) with a longer mean OS (29.3 months) and higher texture variation (>30%), and a high risk group (n=15) with a shorter mean OS (17.7 months) and lower texture variation (<15%).

CONCLUSIONS

Locoregional metabolic texture response provides a feasible approach for evaluating and predicting clinical outcomes following treatment of PA with RT. The proposed method can be used to stratify patient risk and help select appropriate treatment strategies for individual patients toward implementing response-driven adaptive RT.

Clinical data combined with radiological imaging improves the accuracy of TNM staging of pancreatic body and tail adenocarcinoma

PURPOSE

Pancreatic body and tail adenocarcinoma (PBTA) remains one of the deadliest cancers, and current radiological modalities still have limitations on the staging of PBTA. Improving PBTA staging will contribute to the management of this disease.

PATIENTS AND METHODS

Clinicopathological characteristics of 91 surgically treated PBTA patients were retrospectively retrieved. Clinical data associated with postoperative tumor staging (pTNM) were assessed using ordinal logistic regression model. Discriminant analysis was performed using function formula based on multivariate analysis results; further cross-validation was conducted by Bootstrap methods.

RESULTS

Multivariate analysis showed that carbohydrate antigen 19-9 ≥955.0 U/L, albumin, and alkaline phosphatase/total bilirubin ratio were independent factors contributing to improved accuracy of pTNM staging. Discriminant analysis exhibited better performance and showed that the probability of accurate prediction of pTNM stage was 90.6% and the probability of cross-validation was 85.9%. After excluding patients with preoperative diagnosis of stage IV disease, the probability of accurate prediction of pTNM stage was 86.1% and the probability of cross-validation was 75.0%.

CONCLUSION

The combination of imaging and clinical data has higher accuracy in staging PBTA than radiological data alone. A model proposed in this study will improve the management of PBTA.

MRI quantification of pancreas motion as a function of patient setup for particle therapy -a preliminary study

Particle therapy (PT) has shown positive therapeutic results in local control of locally advanced pancreatic lesions. PT effectiveness is highly influenced by target localization accuracy both in space, since the pancreas is located in proximity to radiosensitive vital organs, and in time as it is subject to substantial breathing-related motion. The purpose of this preliminary study was to quantify pancreas range of motion under typical PT treatment conditions. Three common immobilization devices (vacuum cushion, thermoplastic mask, and compressor belt) were evaluated on five male patients in prone and supine positions. Retrospective four-dimensional magnetic resonance imaging data were reconstructed for each condition and the pancreas was manually segmented on each of six breathing phases. A k-means algorithm was then applied on the manually segmented map in order to obtain clusters representative of the three pancreas segments: head, body, and tail. Centers of mass (COM) for the pancreas and its segments were computed, as well as their displacements with respect to a reference breathing phase (beginning exhalation). The median three-dimensional COM displacements were in the range of 3 mm. Latero-lateral and superior-inferior directions had a higher range of motion than the anterior-posterior direction. Motion analysis of the pancreas segments showed slightly lower COM displacements for the head cluster compared to the tail cluster, especially in prone position. Statistically significant differences were found within patients among the investigated setups. Hence a patient-specific approach, rather than a general strategy, is suggested to define the optimal treatment setup in the frame of a millimeter positioning accuracy.

Iontophoretic device delivery for the localized treatment of pancreatic ductal adenocarcinoma

Poor delivery and systemic toxicity of many cytotoxic agents, such as the recent promising combination chemotherapy regimen of folinic acid (leucovorin), fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX), restrict their full utility in the treatment of pancreatic cancer. Local delivery of chemotherapies has become possible using iontophoretic devices that are implanted directly onto pancreatic tumors. We have fabricated implantable iontophoretic devices and tested the local iontophoretic delivery of FOLFIRINOX for the treatment of pancreatic cancer in an orthotopic patient-derived xenograft model. Iontophoretic delivery of FOLFIRINOX was found to increase tumor exposure by almost an order of magnitude compared with i.v. delivery with substantially lower plasma concentrations. Mice treated for 7 wk with device FOLFIRINOX experienced significantly greater tumor growth inhibition compared with i.v. FOLFIRINOX. A marker of cell proliferation, Ki-67, was stained, showing a significant reduction in tumor cell proliferation. These data capitalize on the unique ability of an implantable iontophoretic device to deliver much higher concentrations of drug to the tumor compared with i.v. delivery. Local iontophoretic delivery of cytotoxic agents should be considered for the treatment of patients with unresectable nonmetastatic disease and for patients with the need for palliation of local symptoms, and may be considered as a neoadjuvant approach to improve resection rates and outcome in patients with localized and locally advanced pancreatic cancer.

Primary analysis for clinical efficacy of immunotherapy in patients with pancreatic cancer

Aims: Immunotherapy is an important treatment for pancreatic cancer (PC) patients. To evaluate the therapeutic efficacy of immunotherapy in the treatment of PC, we performed a systemic review and meta-analysis of the relevant published clinical trials, collectively referred to as DC, DC-CIK, LAK, NK and GM-CSF secreting PC cell lines. Materials & methods: A total of 413 patients in 11 eligible trials with PC were selected for the present meta-analysis. Results: The estimated pooled overall survival showed a significant improvement for PC patients who received immunotherapy compared with nonimmunotherapy. The lymphocyte subsets, immune cytokine levels and serum cancer markers in the peripheral blood of PC patients were significantly improved after immunotherapy. Conclusion: The results showed that immunotherapy can improve the efficacy of the treatment of PC patients.

Chinese Herbal Medicines as an Adjunctive Therapy for Unresectable Pancreatic Cancer: A Systematic Review and Meta-Analysis

Pancreatic cancer is a common malignancy with a high mortality. Most patients present clinically with advanced pancreatic cancer. Moreover, the effect of radiotherapy or chemotherapy is limited. Complementary and alternative medicines represent exciting adjunctive therapies. In this study, we ascertained the beneficial and adverse effects of Chinese herbal medicine (CHM) in combination with conventional therapy for inoperable pancreatic cancer by using meta-analysis methods for controlled clinical trials. We extracted data for studies searched from six electronic databases that were searched and also assessed the methodological quality of the included studies. We evaluated the following outcome measures: 6-month and 1-year survival rate, objective response rate, disease control rate, quality of life, and adverse effects. The final analysis showed CHM is a promising strategy as an adjunctive therapy to treat advanced or inoperable pancreatic cancer and that CHM in combination with conventional therapy is a promising strategy for resistant disease. However, convincing evidence must be obtained and confirmed by high-quality trials in future studies.

The biological role of actinin-4 (ACTN4) in malignant phenotypes of cancer

Invasion and metastasis are malignant phenotypes in cancer that lead to patient death. Cell motility is involved in these processes. In 1998, we identified overexpression of the actin-bundling protein actinin-4 in several types of cancer. Protein expression of actinin-4 is closely associated with the invasive phenotypes of cancers. Actinin-4 is predominantly expressed in the cellular protrusions that stimulate the invasive phenotype in cancer cells and is essential for formation of cellular protrusions such as filopodia and lamellipodia. ACTN4 (gene name encoding actinin-4 protein) is located on human chromosome 19q. ACTN4 amplification is frequently observed in patients with carcinomas of the pancreas, ovary, lung, and salivary gland, and patients with ACTN4 amplifications have worse outcomes than patients without amplification. In addition, nuclear distribution of actinin-4 is frequently observed in small cell lung, breast, and ovarian cancer. Actinin-4, when expressed in cancer cell nuclei, functions as a transcriptional co-activator. In this review, we summarize recent developments regarding the biological roles of actinin-4 in cancer invasion.

Impact of Comorbidity and Age on Determinants Therapeutic Strategies in Advanced Pancreatic Head Cancer Patients With Obstructive Jaundices

The current retrospective study aimed to investigate the relationship between prognostic factors and overall survival (OS) in patients with advanced pancreatic head cancers who initially presented with obstructive jaundice. Furthermore, the impact of age and comorbidities on therapeutic strategies in such patients was evaluated.A total of 79 advanced pancreatic head cancer patients who were treated at our institution between January 2006 and November 2013 were reviewed. We analyzed OS risk factors including sex, age, laboratory characteristics, Eastern Cooperative Oncology Group performance status, Charlson Comorbidity Index Scores (CCIS), and therapeutic strategies using Cox proportional hazards regression models.There was no difference in the OS of patients according to the type biliary drainage procedure they underwent. Other related factors, such as better performance status, lower CCIS, and receiving chemotherapy significantly correlated with survival in multivariate analyses. There was a significant survival benefit in systemic chemotherapy compared to best supportive care (BSC) or local radiotherapy. However, no survival benefit was found in elderly patients (age >70 years) undergoing systemic therapy compared to younger patients, except in those elderly patients with CCIS ≤ 1.In advanced pancreatic head cancer patients with obstructive jaundice, systemic therapy and adequate biliary drainage were still the most effective procedures for improving OS in the general population. However, in elderly patients with relatively higher CCIS, BSC with adequate biliary drainage was palliative and no less effective than systemic/local therapies.

Caveolin-1 is Associated with Tumor Progression and Confers a Multi-Modality Resistance Phenotype in Pancreatic Cancer

Caveolin-1 (Cav-1) is a 21 kDa protein enriched in caveolae, and has been implicated in oncogenic cell transformation, tumorigenesis, and metastasis. We explored roles for Cav-1 in pancreatic cancer (PC) prognostication, tumor progression, resistance to therapy, and whether targeted downregulation could lead to therapeutic sensitization. Cav-1 expression was assessed in cell lines, mouse models, and patient samples, and knocked down in order to compare changes in proliferation, invasion, migration, response to chemotherapy and radiation, and tumor growth. We found Cav-1 is overexpressed in human PC cell lines, mouse models, and human pancreatic tumors, and is associated with worse tumor grade and clinical outcomes. In PC cell lines, disruption/depletion of caveolae/Cav-1 reduces proliferation, colony formation, and invasion. Radiation and chemotherapy up-regulate Cav-1 expression, while Cav-1 depletion induces both chemosensitization and radiosensitization through altered apoptotic and DNA repair signaling. In vivo, Cav-1 depletion significantly attenuates tumor initiation and growth. Finally, Cav-1 depletion leads to altered JAK/STAT, JNK, and Src signaling in PC cells. Together, higher Cav-1 expression is correlated with worse outcomes, is essential for tumor growth and invasion (both in vitro and in vivo), is responsible for promoting resistance to therapies, and may serve as a prognostic/predictive biomarker and target in PC.

Isoquercitrin inhibits the progression of pancreatic cancer in vivo and in vitro by regulating opioid receptors and the mitogen-activated protein kinase signalling pathway

Pancreatic cancer is a common malignant tumour that affects individuals worldwide. In recent years, the incidence and mortality rates of pancreatic cancer have continuously increased. Currently, the primary clinical treatment methods for pancreatic cancer include surgical resection, chemotherapy and radiotherapy. However, these treatment methods rarely produce satisfactory therapeutic outcomes. Extensive research has also proven that the effective components of several traditional Chinese medicines, particularly flavonoids extracted from plants, have significant antitumour effects. Isoquercitrin, which is one of the flavonoids found in Bidens pilosa extracts, has a significant antitumour effect. However, the antitumour effect of isoquercitrin and its mechanism of action remain unclear. The objective of the present study was to investigate the effect of isoquercitrin on the progression of pancreatic cancer and to further understand the biological characteristics of the participation of isoquercitrin in the progression of pancreatic cancer. In vitro, we found that a therapeutic dose of isoquercitrin significantly inhibited proliferation, promoted apoptosis and induced cell cycle arrest within the G1 phase in pancreatic cancer cells. Isoquercitrin activated caspase-3, -8 and -9 and reduced the mitochondrial membrane potential. In addition, isoquercitrin inhibited the expression level of the δ opioid receptor; however, isoquercitrin had no effect on the κ and µ opioid receptors. Furthermore, isoquercitrin inhibited extracellular signal-regulated kinase (ERK) phosphorylation and promoted c-Jun N-terminal kinase (JNK) phosphorylation. In vivo, we found that a therapeutic dose of isoquercitrin significantly inhibited xenograft growth in nude mice. In summary, the present study demonstrated that isoquercitrin inhibits human pancreatic cancer progression in vivo and in vitro and that its molecular mechanism may be closely related to opioid receptors and to the activation of the mitogen-activated protein kinase (MAPK) signalling pathway.

ACTN4 copy number increase as a predictive biomarker for chemoradiotherapy of locally advanced pancreatic cancer

Background:

Several clinical trials have compared chemotherapy alone and chemoradiotherapy (CRT) for locally advanced pancreatic cancer (LAPC) treatment. However, predictive biomarkers for optimal therapy of LAPC remain to be identified.

We retrospectively estimated amplification of the ACTN4 gene to determine its usefulness as a predictive biomarker for LAPC.

Methods:

The copy number of ACTN4 in 91 biopsy specimens of LAPC before treatment was evaluated using fluorescence in situ hybridisation (FISH).

Results:

There were no statistically significant differences in overall survival (OS) or progression-free survival (PFS) of LAPC between patients treated with chemotherapy alone or with CRT. In a subgroup analysis of patients treated with CRT, patients with a copy number increase (CNI) of ACTN4 had a worse prognosis of OS than those with a normal copy number (NCN) of ACTN4 (P=0.0005, log-rank test). However, OS in the subgroup treated with chemotherapy alone was not significantly different between patients with a CNI and a NCN of ACTN4. In the patients with a NCN of ACTN4, the median survival time of PFS in CRT-treated patients was longer than that of patients treated with chemotherapy alone (P=0.049).

Conclusions:

The copy number of ACTN4 is a predictive biomarker for CRT of LAPC.

RGS16, a novel p53 and pRb cross-talk candidate inhibits migration and invasion of pancreatic cancer cells

Data collected since the discovery of p53 and pRb/RB1 suggests these tumor suppressors cooperate to inhibit tumor progression. Patients who have mutations in both p53 and RB1 genes have increased tumor reoccurrence and decreased survival compared to patients with only one tumor suppressor gene inactivated. It remains unclear how p53 and pRb cooperate toward inhibiting tumorigenesis. Using RNA expression profiling we identified 179 p53 and pRb cross-talk candidates in normal lung fibroblasts (WI38) cells exogenously coexpressing p53 and pRb. Regulator of G protein signaling 16 (RGS16) was among the p53 and pRb cross-talk candidates and has been implicated in inhibiting activation of several oncogenic pathways associated with proliferation, migration, and invasion of cancer cells. RGS16 has been found to be downregulated in pancreatic cancer patients with metastases compared to patients without metastasis. Expression of RGS16 mRNA was decreased in the pancreatic cancer cell lines tested compared to control. Expression of RGS16 inhibited migration of the BxPC-3 and AsPC-1 but not PANC-1 cells and inhibited invasion of BxPC-3 and AsPC-1 cells with no impact on cell viability. We have identified for the first time p53 and pRb cross-talk candidates and a role for RGS16 to inhibit pancreatic cancer migration and invasion.