Treatment for pancreatic cancer: current therapy and continued progress

The Current Landscape of Clinical Trials for Immunotherapy in Pancreatic Cancer: A State-of-the-Art Review

BACKGROUND

Pancreatic cancer remains a lethal malignancy with a 5-year survival rate below 6% and about 500,000 deaths annually worldwide. Pancreatic adenocarcinoma, the most prevalent form, is commonly associated with diabetes, chronic pancreatitis, obesity, and smoking, mainly affecting individuals aged 60 to 80 years. This systematic review aims to evaluate the efficacy of immunotherapeutic approaches in the treatment of pancreatic cancer.

METHODS

A systematic search was conducted to identify clinical trials (Phases I-III) assessing immunotherapy in pancreatic cancer in PubMed/Medline, CINAHL, Scopus, and Web of Science, adhering to PRISMA Statement 2020 guidelines. The final search was completed on May 25, 2024. Ongoing trials were sourced from ClinicalTrials.gov and the World Health Organization's International Clinical Trials Registry Platform (ICTRP). Keywords such as "pancreatic," "immunotherapy," "cancer," and "clinical trial" were used across databases. Gray literature was excluded.

RESULTS

Phase I trials, involving 337 patients, reported a median overall survival (OS) of 13.6 months (IQR: 5-62.5 months) and a median progression-free survival (PFS) of 5.1 months (IQR: 1.9-11.7 months). Phase II/III trials pooled in a total of 1463 participants had a median OS of 12.2 months (IQR: 2.5-35.55 months) and a median PFS of 8.8 months (IQR: 1.4-33.51 months).

CONCLUSIONS

Immunotherapy shows potential for extending survival among pancreatic cancer patients, though results vary. The immunosuppressive nature of the tumor microenvironment and diverse patient responses underline the need for further research to optimize these therapeutic strategies.

Identifying the Morphological and Molecular Features of a Cell-Based Orthotopic Pancreatic Cancer Mouse Model during Growth over Time

Pancreatic ductal adenocarcinoma (PDAC), characterized by hypovascularity, hypoxia, and desmoplastic stroma is one of the deadliest malignancies in humans, with a 5-year survival rate of only 7%. The anatomical location of the pancreas and lack of symptoms in patients with early onset of disease accounts for late diagnosis. Consequently, 85% of patients present with non-resectable, locally advanced, or advanced metastatic disease at diagnosis and rely on alternative therapies such as chemotherapy, immunotherapy, and others. The response to these therapies highly depends on the stage of disease at the start of therapy. It is, therefore, vital to consider the stages of PDAC models in preclinical studies when testing new therapeutics and treatment modalities. We report a standardized induction of cell-based orthotopic pancreatic cancer models in mice and the identification of vital features of their progression by ultrasound imaging and histological analysis of the level of pancreatic stellate cells, mature fibroblasts, and collagen. The results highlight that early-stage primary tumors are secluded in the pancreas and advance towards infiltrating the omentum at week 5-7 post implantation of the BxPC-3 and Panc-1 models investigated. Late stages show extensive growth, the infiltration of the omentum and/or stomach wall, metastases, augmented fibroblasts, and collagen levels. The findings can serve as suggestions for defining growth parameter-based stages of orthotopic pancreatic cancer models for the preclinical testing of drug efficacy in the future.

Integrated proteomic profiling identifies amino acids selectively cytotoxic to pancreatic cancer cells

Pancreatic adenocarcinoma (PDAC) is one of the most deadly cancers, characterized by extremely limited therapeutic options and a poor prognosis, as it is often diagnosed during late disease stages. Innovative and selective treatments are urgently needed, since current therapies have limited efficacy and significant side effects. Through proteomics analysis of extracellular vesicles, we discovered an imbalanced distribution of amino acids secreted by PDAC tumor cells. Our findings revealed that PDAC cells preferentially excrete proteins with certain preferential amino acids, including isoleucine and histidine, via extracellular vesicles. These amino acids are associated with disease progression and can be targeted to elicit selective toxicity to PDAC tumor cells. Both in vitro and in vivo experiments demonstrated that supplementation with these specific amino acids effectively eradicated PDAC cells. Mechanistically, we also identified XRN1 as a potential target for these amino acids. The high selectivity of this treatment method allows for specific targeting of tumor metabolism with very low toxicity to normal tissues. Furthermore, we found this treatment approach is easy-to-administer and with sustained tumor-killing effects. Together, our findings reveal that exocytosed amino acids may serve as therapeutic targets for designing treatments of intractable PDAC and potentially offer alternative treatments for other types of cancers.

Therapeutic effect of a MUC1-specific monoclonal antibody-drug conjugates against pancreatic cancer model

BACKGROUND

Pancreatic cancer is one of the most aggressive malignancies without effective targeted therapies. MUC1 has emerged as a potential common target for cancer therapy because it is overexpressed in a variety of different cancers including the majority of pancreatic cancer. However, there are still no approved monoclonal antibody drugs targeting MUC1 have been reported. Recently, we generated a humanized MUC1 antibody (HzMUC1) specific to the interaction region between MUC1-N and MUC1-C. In this study, we generated the antibody drug conjugate (ADC) by conjugating HzMUC1 with monomethyl auristatin (MMAE), and examined the efficacy of HzMUC1-MMAE against the MUC1-positive pancreatic cancer in vitro and in vivo.

METHODS

Western blot and immunoprecipitation were used to detect MUC1 in pancreatic cancer cells. MUC1 localization in pancreatic cancer cells was determined by confocal microscopy. HzMUC1 was conjugated with the monomethyl auristatin (MMAE), generating the HzMUC1-MMAE ADC. Colony formation assay and flow cytometry were used to assess the effects of the HzMUC1-MMAE cell viability, cell cycle progression and apoptosis. Capan-2 and CFPAC-1 xenograft model were used to test the efficacy of HzMUC1-MMAE against pancreatic cancer.

RESULTS

HzMUC1 antibody binds to MUC1 on the cell surface of pancreatic cancer cells. HzMUC1-MMAE significantly inhibited cell growth by inducing G2/M cell cycle arrest and apoptosis in pancreatic cancer cells. Importantly, HzMUC1-MMAE significantly reduced the growth of pancreatic xenograft tumors by inhibiting cell proliferation and enhancing cell death.

CONCLUSION

Our results indicate that HzMUC1-ADC is a promising novel targeted therapy for pancreatic cancer. HzMUC1-ADC should also be an effective drug for the treatment of different MUC1-positive cancers.

β-Sheet Richness of the Circulating Tumor-Derived Extracellular Vesicles for Noninvasive Pancreatic Cancer Screening

Tumor-derived extracellular vesicles (EVs) are under intensive study for their potential as noninvasive diagnosis biomarkers. Most EV-based cancer diagnostic assays trace supernumerary of a single cancer-associated marker or marker signatures. These types of biomarker assays are either subtype-specific or vulnerable to be masked by high background signals. In this study, we introduce using the β-sheet richness (BR) of the tumor-derived EVs as an effective way to discriminate EVs originating from malignant and nonmalignant cells, where EV contents are evaluated as a collective attribute rather than single factors. Circular dichroism, Fourier transform infrared spectroscopy, fluorescence staining assays, and a de novo workflow combining proteomics, bioinformatics, and protein folding simulations were employed to validate the collective attribute at both cellular and EV levels. Based on the BR of the tumorous EVs, we integrated immunoprecipitation and fluorescence labeling targeting the circulating tumor-derived EVs in serum and developed the process into a clinical assay, named EvIPThT. The assay can distinguish patients with and without malignant disease in a pilot cohort, with weak correlations to prognosis biomarkers, suggesting the potential for a cancer screening panel with existing prognostic biomarkers to improve overall performance.

Radiomic analysis to predict local response in locally advanced pancreatic cancer treated with stereotactic body radiation therapy

PURPOSE

Aim of this study is to assess the ability of contrast-enhanced CT image-based radiomic analysis to predict local response (LR) in a retrospective cohort of patients affected by pancreatic cancer and treated with stereotactic body radiation therapy (SBRT). Secondary aim is to evaluate progression free survival (PFS) and overall survival (OS) at long-term follow-up.

METHODS

Contrast-enhanced-CT images of 37 patients who underwent SBRT were analyzed. Two clinical variables (BED, CTV volume), 27 radiomic features were included. LR was used as the outcome variable to build the predictive model. The Kaplan-Meier method was used to evaluate PFS and OS.

RESULTS

Three variables were statistically correlated with the LR in the univariate analysis: Intensity Histogram (StdValue feature), Gray Level Cooccurrence Matrix (GLCM25_Correlation feature) and Neighbor Intensity Difference (NID25_Busyness feature). Multivariate model showed GLCM25_Correlation (P = 0.007) and NID25_Busyness (P = 0.03) as 2 independent predictive variables for LR. The odds ratio values of GLCM25_Correlation and NID25_Busyness were 0.07 (95%CI 0.01-0.49) and 8.10 (95%CI 1.20-54.40), respectively. The area under the curve for the multivariate logistic regressive model was 0.851 (95%CI 0.724-0.978). At a median follow-up of 30 months, median PFS was 7 months (95%CI 6-NA); median OS was 11 months (95%CI 10-22 months).

CONCLUSIONS

This analysis identified a radiomic signature that correlates with LR. To confirm these results, prospective studies could identify patient sub-groups with different rates of radiation dose-response to define a more personalized SBRT approach.

Pancreatic Cancer Survival Prediction: A Survey of the State-of-the-Art

Cancer early detection increases the chances of survival. Some cancer types, like pancreatic cancer, are challenging to diagnose or detect early, and the stages have a fast progression rate. This paper presents the state-of-the-art techniques used in cancer survival prediction, suggesting how these techniques can be implemented in predicting the overall survival of pancreatic ductal adenocarcinoma cancer (pdac) patients. Because of bewildering and high volumes of data, the recent studies highlight the importance of machine learning (ML) algorithms like support vector machines and convolutional neural networks. Studies predict pancreatic ductal adenocarcinoma cancer (pdac) survival is within the limits of 41.7% at one year, 8.7% at three years, and 1.9% at five years. There is no significant correlation found between the disease stages and the overall survival rate. The implementation of ML algorithms can improve our understanding of cancer progression. ML methods need an appropriate level of validation to be considered in everyday clinical practice. The objective of these techniques is to perform classification, prediction, and estimation. Accurate predictions give pathologists information on the patient's state, surgical treatment to be done, optimal use of resources, individualized therapy, drugs to prescribe, and better patient management.

Chinese Propolis Suppressed Pancreatic Cancer Panc-1 Cells Proliferation and Migration via Hippo-YAP Pathway

Pancreatic cancer is one of the most malignant cancers with high mortality. Therefore, it is of great urgency to develop new agents that could improve the prognosis of Pancreatic cancer patients. Chinese propolis (CP), a flavonoid-rich beehive product, has been reported to have an anticancer effect. In this study, we applied CP to the human Pancreatic cancer cell line Panc-1 to verify its impact on tumor development. CP induced apoptosis in Panc-1 cells from 12.5 µg/mL in a time- and dose-dependent manner with an IC₅₀ value of approximately 50 µg/mL. Apoptosis rate induced by CP was examined by Annexing FITC/PI assay. We found that 48 h treatment with 50 µg/mL CP resulted in 34.25 ± 3.81% apoptotic cells, as compared to 9.13 ± 1.76% in the control group. We further discovered that the Panc-1 cells tended to be arrested at G2/M phase after CP treatment, which is considered to contribute to the anti-proliferation effect of CP. Furthermore, our results demonstrated that CP suppressed Panc-1 cell migration by regulating epithelial-mesenchymal transition (EMT). Interestingly, the Hippo pathway was activated in Panc-1 cells after CP treatment, serving as a mechanism for the anti-pancreatic cancer effect of CP. These findings provide a possibility of beehive products as an alternative treatment for pancreatic cancer.

Percutaneous Radiofrequency Ablation for Metachronous Hepatic Metastases after Curative Resection of Pancreatic Adenocarcinoma

OBJECTIVE

To retrospectively evaluate the safety and efficacy of percutaneous radiofrequency ablation (RFA) in patients with metachronous hepatic metastases arising from pancreatic adenocarcinoma who had previously received curative surgery.

MATERIALS AND METHODS

Between 2002 and 2017, percutaneous RFA was performed on 94 metachronous hepatic metastases (median diameter, 1.5 cm) arising from pancreatic cancer in 60 patients (mean age, 60.5 years). Patients were included if they had fewer than five metastases, a maximum tumor diameter of ≤ 5 cm, and disease confined to the liver or stable extrahepatic disease. For comparisons during the same period, we included 66 patients who received chemotherapy only and met the same eligibility criteria described.

RESULTS

Technical success was achieved in all hepatic metastasis without any procedure-related mortality. During follow-up, local tumor progression of treated lesions was observed in 38.3% of the tumors. Overall median survival and 3-year survival rates were 12 months and 0%, respectively from initial RFA, and 14.7 months and 2.1%, respectively from the first diagnosis of liver metastasis. Multivariate analysis showed that a large tumor diameter of > 1.5 cm, a late TNM stage (≥ IIB) before curative surgery, a time from surgery to recurrence of < 1 year, and the presence of extrahepatic metastasis, were all prognostic of reduced overall survival after RFA. Median overall (12 months vs. 9.1 months, p = 0.094) and progression-free survival (5 months vs. 3.3 months, p = 0.068) were higher in the RFA group than in the chemotherapy group with borderline statistical difference.

CONCLUSION

RFA is safe and may offer successful local tumor control in patients with metachronous hepatic metastases arising from pancreatic adenocarcinoma. Patients with a small diameter tumor, early TNM stage before curative surgery, late hepatic recurrence, and liver-only metastasis benefit most from RFA treatment. RFA provided better survival outcomes than chemotherapy for this specific group with borderline statistical difference.

Proteostasis Dysregulation in Pancreatic Cancer

The most common form of pancreatic cancer, pancreatic ductal adenocarcinoma (PDAC), has a dismal 5-year survival rate of less than 5%. Radical surgical resection, in combination with adjuvant chemotherapy, provides the best option for long-term patient survival. However, only approximately 20% of patients are resectable at the time of diagnosis, due to locally advanced or metastatic disease. There is an urgent need for the identification of new, specific, and more sensitive biomarkers for diagnosis, prognosis, and prediction to improve the treatment options for pancreatic cancer patients. Dysregulation of proteostasis is linked to many pathophysiological conditions, including various types of cancer. In this review, we report on findings relating to the main cellular protein degradation systems, the ubiquitin-proteasome system (UPS) and autophagy, in pancreatic cancer. The expression of several components of the proteolytic network, including E3 ubiquitin-ligases and deubiquitinating enzymes, are dysregulated in PDAC, which accounts for approximately 90% of all pancreatic malignancies. In the future, a deeper understanding of the emerging role of proteostasis in pancreatic cancer has the potential to provide clinically relevant biomarkers and new strategies for combinatorial therapeutic options to better help treat the patients.

Expansion of Circulating Tumor Cells from Patients with Locally Advanced Pancreatic Cancer Enable Patient Derived Xenografts and Functional Studies for Personalized Medicine

Improvement in pancreatic cancer treatment represents an urgent medical goal that has been hampered by the lack of predictive biomarkers. Circulating Tumor Cells (CTCs) may be able to overcome this issue by allowing the monitoring of therapeutic response and tumor aggressiveness through ex vivo expansion. The successful expansion of CTCs is challenging, due to their low numbers in blood and the high abundance of blood cells. Here, we explored the utility of pancreatic CTC cultures as a preclinical model for treatment response. CTCs were isolated from ten patients with locally advanced pancreatic cancer using the Labyrinth, a biomarker independent, size based, inertial microfluidic separation device. Three patient-derived CTC samples were successfully expanded in adherent and spheroid cultures. Molecular and functional characterization was performed on the expanded CTC lines. CTC lines exhibited KRAS mutations, consistent with pancreatic cancers. Additionally, we evaluated take rate and metastatic potential in vivo and examined the utility of CTC lines for cytotoxicity assays. Patient derived expanded CTCs successfully generated patient derived xenograft (PDX) models with a 100% take rate. Our results demonstrate that CTC cultures are possible and provide a valuable resource for translational pancreatic cancer research, while also providing meaningful insight into the development of distant metastasis, as well as treatment resistance.

Prediction of survival after left-sided pancreatic resection for adenocarcinoma: Introduction of a new prognostic score

BACKGROUND

Due to the clinically unapparent course the entity of left-sided pancreatic adenocarcinoma is often diagnosed at advanced stages, resulting in small numbers of patients qualifying for pancreatectomy. This study strives to develop a prognostic model for survival after left-sided pancreatic resection.

METHODS

A total of 54 patients were analyzed. Pre- and intra-operative predictive factors for 18-month mortality were identified with multivariable binary logistic regression analysis and compiled into a prognostic model. The applicability was evaluated by assessment of the area under the receiver operating characteristic curve (AUROC). The model was internally validated applying a randomized backwards bootstrapping analysis.

RESULTS

The 18-month mortality rate was 74.1% (n = 40). Mean survival was 19.1 months. A prognostic model for 18-month mortality after left sided-pancreatectomy showed an AUROC >0.800: 18-month mortality risk in% = Exp(Y) / (1 + Exp(Y)) with y= -0.927 + (1.724, if CA 19-9 elevated, otherwise 0) + (1.212 × number of intra-operative transfused packed red blood cells) + (2.771, if prior abdominal surgery, otherwise 0) - (3.612, if gastric resection, otherwise 0) This model was internally validated in 40 randomized backwards bootstrapping steps with AUROCs ranging from 0.757 to 0.971.

CONCLUSIONS

The 18-month mortality risk for patients after left-sided pancreatectomy for adenocarcinoma of the pancreatic body can be assessed with the number of intra-operatively transfused packed red blood cells, elevated CA 19-9 levels, additional gastric resection and prior abdominal surgeries in the patient's history.

A Novel Monoclonal Antibody Targets Mucin1 and Attenuates Growth in Pancreatic Cancer Model

Mucin1 (MUC1) is a highly glycosylated transmembrane protein that plays a crucial role in the lubrication and protection of normal epithelial cells. However, MUC1 has emerged as a potential target for cancer therapy because it is overexpressed and functions in several types of cancers. Recently, we produced a monoclonal antibody (the anti-hMUC1 antibody) specific to the extracellular region of the MUC1 subunit MUC1-C to evaluate the utility of using anti-MUC1 antibodies in pancreatic cancer models. The anti-hMUC1 antibody recognized the MUC1-C protein in pancreatic cancer cells. Based on immunostaining and confocal image analyses, the anti-hMUC1 antibody initially bound to the cell membrane then was internalized in cancer cells that express MUC1. The anti-hMUC1 antibody suppressed epidermal growth factor (EGF)-mediated extracellular signal–regulated kinase (ERK) phosphorylation and cyclin D1 expression. When the anti-hMUC1 antibody was injected into a xenograft mouse model and traced using an in vivo imaging system, we observed that the anti-hMUC1 antibody was localized to MUC1-expressing pancreatic tumors. Importantly, the anti-hMUC1 monoclonal antibody suppressed pancreatic tumor growth in mice. According to immunohistochemistry analysis using a pancreatic cancer tissue array and the anti-hMUC1 antibody, MUC1 was highly expressed in human pancreatic cancer tissues compared to normal tissues. Therefore, we conclude that the anti-hMUC1 antibody specifically targets MUC1 and suppresses its function in pancreatic cancer in vitro and in vivo and can be further developed as a promising targeted therapy to treat pancreatic cancer.

Combination therapy versus gemcitabine monotherapy in the treatment of elderly pancreatic cancer: a meta-analysis of randomized controlled trials

Purpose

We aimed to compare the efficacy of combination therapy versus gemcitabine monotherapy in the treatment of elderly pancreatic cancer (PC) by using a meta-analysis.

Materials and methods

Databases were searched to identify relevant clinical trials. Hazard ratios (HRs) were used to estimate overall survival (OS) and progression-free survival (PFS). Statistical analyses were conducted by using Comprehensive Meta Analysis software (version 2.0).

Results

=0.009) in comparison with gemcitabine alone. No publication bias was detected by Begg's and Egger's tests for OS.

Conclusion

The findings of this study suggest that combined chemotherapy, but not for gemcitabine plus targeted agents, could be recommended for elderly PC patients due to its survival benefits. Further studies are still needed to assess the treatment tolerance of combination chemotherapy in these patient populations.

Distal Pancreatectomy with En Bloc Resection of the Celiac Axis with Preservation or Reconstruction of the Left Gastric Artery in Patients with Pancreatic Body Cancer

BACKGROUND

A distal pancreatectomy with en bloc celiac axis resection (DP-CAR) is indicated for left-sided locally advanced pancreatic ductal adenocarcinoma. However, ischemic complication resulting from the sacrifice of the common hepatic artery and left gastric artery (LGA) remain problematic. The aim of this study was to analyze the feasibility of DP-CAR with preservation or reconstruction of the left gastric artery.

METHOD

Between April 2011 and December 2014, we treated 17 cases using DP-CAR with preservation or reconstruction of the LGA. If the tumor had involved the LGA, the LGA was dissected and reconstructed using the middle colic artery. We retrospectively analyzed the feasibility of this procedure.

RESULTS

Among 17 consecutive patients who underwent DP-CAR, the LGA was preserved in 13 patients and reconstructed in four patients. Major postoperative complications were observed in seven cases (41 %). A pancreatic fistula (grade B/C) or delayed gastric emptying (grade B/C) occurred in 7 (41 %) and 2 (12 %) cases, respectively. The overall R0 resection rate was 94 % (16/17). Eleven cases developed recurrences (liver, n = 4; lymph nodes, n = 2; peritoneal dissemination, n = 2; lung, n = 2; local recurrence, n = 1). The overall 1- and 3-year postoperative survival rates were 74 and 45 %, respectively.

CONCLUSIONS

Our preliminary data showed that DP-CAR with preservation or reconstruction of the LGA is a safe and feasible approach, and that this procedure may reduce the risk of ischemic complications.

EUS-guided fine-needle injection of gemcitabine for locally advanced and metastatic pancreatic cancer

BACKGROUND AND AIMS

Among the greatest hurdles to pancreatic cancer (PC) therapy is the limited tissue penetration of systemic chemotherapy because of tumor desmoplasia. The primary study aim was to determine the toxicity profile of EUS-guided fine-needle injection (EUS-FNI) with gemcitabine. Secondary endpoints included the ability to disease downstage leading to an R0 resection and overall survival (OS) at 6 months, 12 months, and 5 years after therapy.

METHODS

In a prospective study from a tertiary referral center, gemcitabine (38 mg/mL) EUS-FNI was performed in patients with PC before conventional therapy. Initial and delayed adverse events (AEs) were assessed within 72 hours and 4 to 14 days after EUS-FNI, respectively. Patients were followed for ≥5 years or until death.

RESULTS

Thirty-six patients with stage II (n = 3), stage III (n = 20), or stage IV (n = 13) disease underwent gemcitabine EUS-FNI with 2.5 mL (.7-7.0 mg) total volume of injectate per patient. There were no initial or delayed AEs reported. Thirty-five patients (97.2%) were deceased at the time of analysis with a median 10.3 months of follow-up (range, 3.1-63.9). OS at 6 months and 12 months was 78% and 44%, respectively. The median OS was 10.4 months (range, 2.7-68). Among patients with stage III unresectable disease, 4 (20%) were downstaged and underwent an R0 resection.

CONCLUSIONS

Our study suggests the feasibility, safety, and potential efficacy of gemcitabine EUS-FNI for PC. Additional data are needed to verify these observations and to determine the potential role relative to conventional multimodality therapy.

Advanced pancreatic ductal adenocarcinoma - Complexities of treatment and emerging therapeutic options

Pancreatic ductal adenocarcinoma is a devastating disease with a poor prognosis regardless of stage. To date the mainstay of therapy for advanced disease has been chemotherapy with little incremental improvements in outcome. Despite extensive research investigating new treatment options the current practices continue to utilise fluorouracil or gemcitabine containing combinations. The need for novel therapeutic approaches is mandated by the ongoing poor survival rates associated with this disease. One such approach may include manipulation of ribosome biogenesis and the nucleolar stress response, which has recently been applied to haematological malignancies such as lymphoma and prostate cancer with promising results. This review will focus on the current therapeutic options for pancreatic ductal adenocarcinoma and the complexities associated with developing novel treatments, with a particular emphasis on the role of the nucleolus as a treatment strategy.

Expression of truncated bile salt-dependent lipase variant in pancreatic pre-neoplastic lesions

Pancreatic adenocarcinoma (PDAC) is a dismal disease. The lack of specific symptoms still leads to a delay in diagnosis followed by death within months for most patients. Exon 11 of the bile salt-dependent lipase (BSDL) gene encoding variable number of tandem repeated (VNTR) sequences has been involved in pancreatic pathologies. We hypothesized that BSDL VNTR sequences may be mutated in PDAC. The amplification of BSDL VNTR from RNA extracted from pancreatic SOJ-6 cells allowed us to identify a BSDL amplicon in which a cytosine residue is inserted in a VNTR sequence. This insertion gives rise to a premature stop codon, resulting in a truncated protein and to a modification of the C-terminal amino-acid sequence; that is PRAAHG instead of PAVIRF. We produced antibodies directed against these sequences and examined pancreatic tissues from patients with PDAC and PanIN. Albeit all tissues were positive to anti-PAVIRF antibodies, 72.2% of patient tissues gave positive reaction with anti-PRAAHG antibodies, particularly in dysplastic areas of the tumor. Neoplastic cells with ductal differentiation were not reactive to anti-PRAAHG antibodies. Some 70% of PanIN tissues were also reactive to anti-PRAAHG antibodies, suggesting that the C insertion occurs early during pancreatic carcinogenesis. Data suggest that anti-PRAAHG antibodies were uniquely reactive with a short isoform of BSDL specifically expressed in pre-neoplastic lesions of the pancreas. The detection of truncated BSDL reactive to antibodies against the PRAAHG C-terminal sequence in pancreatic juice or in pancreatic biopsies may be a new tool in the early diagnosis of PDAC.

Rs488087 single nucleotide polymorphism as predictive risk factor for pancreatic cancers

Pancreatic cancer (PC) is a devastating disease progressing asymptomatically until death within months after diagnosis. Defining at-risk populations should promote its earlier diagnosis and hence also avoid its development. Considering the known involvement in pancreatic disease of exon 11 of the bile salt-dependent lipase (BSDL) gene that encodes variable number of tandem repeat (VNTR) sequences, we hypothesized upon the existence of a genetic link between predisposition to PC and mutations in VNTR loci. To test this, BSDL VNTR were amplified by touchdown-PCR performed on genomic DNA extracted from cancer tissue or blood samples from a French patient cohort and amplicons were Sanger sequenced. A robust method using probes for droplet digital (dd)-PCR was designed to discriminate the C/C major from C/T or T/T minor genotypes. We report that the c.1719C > T transition (SNP rs488087) present in BSDL VNTR may be a useful marker for defining a population at risk of developing PC (occurrence: 63.90% in the PC versus 27.30% in the control group). The odds ratio of 4.7 for the T allele was larger than those already determined for other SNPs suspected to be predictive of PC. Further studies on tumor pancreatic tissue suggested that a germline T allele may favor Kras G12R/G12D somatic mutations which represent negative prognostic factors associated with reduced survival. We propose that the detection of the T allele in rs488087 SNP should lead to an in-depth follow-up of patients in whom an association with other potential risk factors of pancreatic cancer may be present.

Improved survival after palliative resection of unsuspected stage IV pancreatic ductal adenocarcinoma

BACKGROUND

Palliative resection of stage IV pancreatic ductal adenocarcinoma (PDAC) has not shown its benefit until now. In our retrospective review, we compared the results of palliative resection to non-resection.

METHODS

Between 2000 and 2009, metastasis of PDAC was confirmed in the operating room in 150 patients. 35 underwent palliative resection (resection group; R) and 115 did bypass or biopsy. 35 patients (biopsy or bypass group: NR) in the 115 patients were matched with the patients undergoing resection for tumor size and the metastasis of peritoneal seeding. Demographic, clinical, operative data and survival were analyzed.

RESULTS

There was no significant difference of major complication (Clavien-Dindo classification 3-5) between two groups. There was no 30-day mortality in either group. More patients in R received postoperative chemotherapy (82.9% vs. 57.1%; P = 0.019). Multivariate analysis showed resection and postoperative chemotherapy as independent factor related to survival (hazard ratio, 0.44; 95% CI, 0.25-0.76; P = 0.003). Patients in R showed better survival rates compared to those in NR (P < 0.001).

CONCLUSION

Our study suggests resection for stage IV PDAC can be associated with increased survival. In patients of stage IV PDAC, palliative resection with chemotherapy could have some benefit in selected patients.

Identifying Factors Influencing Pancreatic Cancer Management to Inform Quality Improvement Efforts and Future Research: A Scoping Systematic Review

Pancreatic cancer (PC) patients appear to receive suboptimal care. We conducted a systematic review to identify factors that influence PC management which are amenable to quality improvement. MEDLINE, EMBASE, and the references of eligible studies were searched from 1996 to July 2014. Two authors independently selected and reviewed eligible studies. Identified factors were mapped onto a framework of determinants of care delivery and outcomes. Methodological quality of studies was assessed using Downs and Black criteria. Most of the 33 eligible studies were population-based observational studies conducted in the United States. Patient (age, socioeconomic status, race) and institutional (case volume, academic status) factors influence care delivery and outcomes (complications, mortality, readmission, survival). Two studies implemented interventions to improve quality of care (centralization to high-volume hospitals, multidisciplinary care). One study examined system determinants (referral wait times). No studies examined the influence of guideline or provider characteristics. The overall lack of health services research in PC is striking. Factors and interventions identified here can be used to plan PC quality improvement programs. Further research is needed to explore the influence of guideline and provider factors on PC management and evaluate the impact of quality improvement interventions.

Unraveling the complexity of autophagy: Potential therapeutic applications in Pancreatic Ductal Adenocarcinoma

Autophagy is a highly dynamic, evolutionary conserved cellular homeostatic process that occurs at baseline levels in most cells. It exerts predominantly cytoprotective effects by removing damaged organelles and protein aggregates. In cancer, however, autophagy acts as both a tumor suppressor by preventing ROS-induced tumorigenesis and as a tumor inducer by providing nutrients to tumor cells under hypoxic, low-energy conditions and protecting them against therapeutically induced stress. Pancreatic Ductal Adenocarcinoma is an extremely lethal and aggressive neoplasm with a 5 year-survival rate between 1% and 5%. One of the most important factors affecting its poor prognosis is its high resistance to most of the existing chemotherapeutic regimens. The role of autophagy in PDAC has been investigated by different research groups and the results are quite divergent; some research lines point at autophagy as a tumor promoting mechanism, whereas other studies assign oncosuppressive functions to it. Nevertheless, several distinct preclinical studies and clinical trials have evaluated the efficacy of both autophagy inducers and autophagy inhibitors as therapeutic compounds against PDAC, many of them providing promising results. Although a better understanding of the complexity of autophagy is needed, the modulation of this process opens new opportunities for prognostic and therapeutic purposes.

Intraoperative blood loss is not a predictor of prognosis for pancreatic cancer

PURPOSE

The relationship between intraoperative blood loss (IBL) and prognosis has been reported for some types of cancer, but not for pancreatic cancer, which has one of the highest mortality rates of any cancer. We conducted this study to analyze the relationship between IBL and clinical outcome for patients undergoing radical surgery for pancreatic cancer.

METHODS

The subjects of this study were 144 patients who underwent curative pancreatectomy for invasive pancreatic cancer between 2002 and 2014. Clinicopathological characteristics were recorded and prognostic factors were identified by univariate and multivariate analyses.

RESULTS

Large IBL was significantly associated with advanced tumor stage, a long operation time, a large tumor, portal vein resection, and blood transfusion. According to univariate analysis, IBL was also significantly associated with overall survival (OS) and relapse-free survival (RFS); however, it was not an independent prognostic factor for OS and RFS in multivariate analysis. According to multivariate analysis, lymph node metastasis and R-status were independent prognostic factors for OS and RFS. A subgroup analysis of patients who received no blood transfusion showed similar results.

CONCLUSION

Minimizing IBL is very important; however, the present study found that positive lymph node metastasis and R-status were stronger independent prognostic factors for pancreatic cancer.

The Antipancreatic Cancer Activity of OSI-027, a Potent and Selective Inhibitor of mTORC1 and mTORC2

In the present study, we investigated the potential activity of OSI-027, a potent and selective mammalian target of rapamycin (mTOR) complex 1/2 (mTORC1/2) dual inhibitor, against pancreatic cancer cells both in vitro and in vivo. We demonstrated that OSI-027 inhibited survival and growth of both primary and transformed (PANC-1 and MIA PaCa-2 lines) human pancreatic cancer cells. Meanwhile, OSI-027 induced caspase-dependent apoptotic death of the pancreatic cancer cells. On the other hand, caspase inhibitors alleviated cytotoxicity by OSI-027. At the molecular level, OSI-027 treatment blocked mTORC1 and mTORC2 activation simultaneously, without affecting ERK-mitogen-activated protein kinase activation. Importantly, OSI-027 activated cytoprotective autophagy in the above cancer cells. Whereas pharmacological blockage of autophagy or siRNA knockdown of Beclin-1 significantly enhanced the OSI-027-induced activity against pancreatic cancer cells. Specifically, a relatively low dose of OSI-027 sensitized gemcitabine-induced pancreatic cancer cell death in vitro. Further, administration of OSI-027 or together with gemcitabine dramatically inhibited PANC-1 xenograft growth in severe combined immunodeficiency mice, leading to significant mice survival improvement. In summary, the preclinical results of this study suggest that targeting mTORC1/2 synchronously by OSI-027 could be further investigated as a valuable treatment for pancreatic cancer.

Polyphenol-rich extract of Salvia chinensis exhibits anticancer activity in different cancer cell lines, and induces cell cycle arrest at the G₀/G₁-phase, apoptosis and loss of mitochondrial membrane potential in pancreatic cancer cells

Pancreatic cancer (PC) is one of the most aggressive types of human malignancy, which has an overall 5-year survival rate of <2%. PC is the fourth most common cause of cancer‑associated mortality in the western world. At present, there is almost no effective treatment available for the treatment of PC. The aim of the present study was to evaluate the anticancer potential of a polyphenol enriched extract obtained from Salvia chinensis, a Chinese medicinal plant. An MTT assay was used to evaluate the cell viability of five cancer cell lines and one normal cell line. In addition, the effects of the extract on apoptotic induction, cell cycle phase distribution, DNA damage and loss of mitochondrial membrane potential (ΛΨm) were evaluated in MiapaCa‑2 human PC cells. The effects of the extract on cell cycle phase distribution and ΛΨm were assessed by flow cytometry, using propidium iodide and rhodamine‑123 DNA‑binding fluorescent dyes, respectively. Fluorescence microscopy, using 4',6‑diamidino‑2‑phenylindole as a staining agent, was performed in order to detect the morphological changes of the MiapaCa‑2 cancer cells and the presence of apoptotic bodies following treatment with the extract. The results of the present study demonstrated that the polyphenol‑rich extract from S. chinensis induced potent cytotoxicity in the MCF‑7 human breast cancer cells, A549 human lung cancer cells, HCT‑116 and COLO 205 human colon cancer cells, and MiapaCa‑2 human PC cells. The Colo 205 and MCF‑7 cancer cell lines were the most susceptible to treatment with the extract, which exhibited increased rate of growth inhibition. Fluorescence microscopy revealed characteristic morphological features of apoptosis and detected the appearance of apoptotic bodies following treatment with the extract in the PC cells. Flow cytometric analysis demonstrated that the extract induced G0/G1 cell cycle arrest in a dose‑dependent manner. In addition, treatment with the extract induced a significant and concentration-dependent reduction in the ΛΨm of the PC cells.

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.

Targeting p110gamma in gastrointestinal cancers: attack on multiple fronts

Phosphoinositide 3-kinases (PI3Ks) regulate several cellular functions that are critical for cancer progression and development, including cell survival, proliferation and migration. Three classes of PI3Ks exist with the class I PI3K encompassing four isoforms of the catalytic subunit known as p110α, p110β, p110γ, and p110δ. Although for many years attention has been mainly focused on p110α recent evidence supports the conclusion that p110β, p110γ, and p110δ can also have a role in cancer. Amongst these, accumulating evidence now indicates that p110γ is involved in several cellular processes associated with cancer and indeed this specific isoform has emerged as a novel important player in cancer progression. Studies from our laboratory have identified a specific overexpression of p110γ in human pancreatic ductal adenocarcinoma (PDAC) and in hepatocellular carcinoma (HCC) tissues compared to their normal counterparts. Our data have further established that selective inhibition of p110γ is able to block PDAC and HCC cell proliferation, strongly suggesting that pharmacological inhibition of this enzyme can directly affect growth of these tumors. Furthermore, increasing evidence suggests that p110γ plays also a key role in the interactions between cancer cells and tumor microenvironment and in particular in tumor-associated immune response. It has also been reported that p110γ can regulate invasion of myeloid cells into tumors and tumor angiogenesis. Finally p110γ has also been directly involved in regulation of cancer cell migration. Taken together these data indicate that p110γ plays multiple roles in regulation of several processes that are critical for tumor progression and metastasis. This review will discuss the role of p110γ in gastrointestinal tumor development and progression and how targeting this enzyme might represent a way to target very aggressive tumors such as pancreatic and liver cancer on multiple fronts.

Bayesian Semi-parametric Analysis of Semi-competing Risks Data: Investigating Hospital Readmission after a Pancreatic Cancer Diagnosis

In the U.S., the Centers for Medicare and Medicaid Services uses 30-day readmission, following hospitalization, as a proxy outcome to monitor quality of care. These efforts generally focus on treatable health conditions, such as pneumonia and heart failure. Expanding quality of care systems to monitor conditions for which treatment options are limited or non-existent, such as pancreatic cancer, is challenging because of the non-trivial force of mortality; 30-day mortality for pancreatic cancer is approximately 30%. In the statistical literature, data that arise when the observation of the time to some non-terminal event is subject to some terminal event are referred to as 'semi-competing risks data'. Given such data, scientific interest may lie in at least one of three areas: (i) estimation/inference for regression parameters, (ii) characterization of dependence between the two events, and (iii) prediction given a covariate profile. Existing statistical methods focus almost exclusively on the first of these; methods are sparse or non-existent, however, when interest lies with understanding dependence and performing prediction. In this paper we propose a Bayesian semi-parametric regression framework for analyzing semi-competing risks data that permits the simultaneous investigation of all three of the aforementioned scientific goals. Characterization of the induced posterior and posterior predictive distributions is achieved via an efficient Metropolis-Hastings-Green algorithm, which has been implemented in an R package. The proposed framework is applied to data on 16,051 individuals diagnosed with pancreatic cancer between 2005-2008, obtained from Medicare Part A. We found that increased risk for readmission is associated with a high comorbidity index, a long hospital stay at initial hospitalization, non-white race, male, and discharge to home care.

Cytotoxicity of gemcitabine enhanced by polyphenolics from Aronia melanocarpa in pancreatic cancer cell line AsPC-1

AIMS

Extending work with brain tumours, the hypothesis that micronutrients may usefully augment anticancer regimens, chokeberry (Aronia melanocarpa) extract was tested to establish whether it has pro-apoptotic effects in AsPC-1, an established human pancreatic cell line, and whether it potentiates cytotoxicity in combination with gemcitabine. Pancreatic cancer was chosen as a target, as its prognosis remains dismal despite advances in therapy.

METHODS

An MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay was used to assess the growth of the single pancreatic cancer cell line AsPC-1, alone and in comparison or combination with gemcitabine. This was backed up by flow cytometric DRAQ7 cell viability analysis. TUNEL assays were also carried out to investigate pro-apoptotic properties as responsible for the effects of chokeberry extract.

RESULTS

Chokeberry extract alone and its IC75 value (1 µg/mL) in combination with gemcitabine were used to assess the growth of the AsPC-1 cell line. Gemcitabine in combination with chokeberry extract was more effective than gemcitabine alone. TUNEL assays showed apoptosis to be a mechanism occurring at 1 µg/mL concentration of chokeberry, with apoptotic bodies detected by both colourimetric and fluorometric methods.

CONCLUSIONS

The implication of this study, using single cancer cell line, is that chemotherapy (at least with gemcitabine) might be usefully augmented with the use of micronutrients such as chokeberry extract.

DNA-PKcs is important for Akt activation and gemcitabine resistance in PANC-1 pancreatic cancer cells

Pancreatic cancer is one of the most aggressive human malignancies with extremely poor prognosis. The moderate activity of the current standard gemcitabine and gemcitabine-based regimens was due to pre-existing or acquired chemo-resistance of pancreatic cancer cells. In this study, we explored the potential role of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) in gemcitabine resistance, and studied the underlying mechanisms. We found that NU-7026 and NU-7441, two DNA-PKcs inhibitors, enhanced gemcitabine-induced cytotoxicity and apoptosis in PANC-1 pancreatic cancer cells. Meanwhile, PANC-1 cells with siRNA-knockdown of DNA-PKcs were more sensitive to gemcitabine than control PANC-1 cells. Through the co-immunoprecipitation (Co-IP) assay, we found that DNA-PKcs formed a complex with SIN1, the latter is an indispensable component of mammalian target of rapamycin (mTOR) complex 2 (mTORC2). DNA-PKcs-SIN1 complexation was required for Akt activation in PANC-1 cells, while inhibition of this complex by siRNA knockdown of DNA-PKcs/SIN1, or by DNA-PKcs inhibitors, prevented Akt phosphorylation in PANC-1 cells. Further, SIN1 siRNA-knockdown also facilitated gemcitabine-induced apoptosis in PANC-1 cells. Finally, DNA-PKcs and p-Akt expression was significantly higher in human pancreatic cancer tissues than surrounding normal tissues. Together, these results show that DNA-PKcs is important for Akt activation and gemcitabine resistance in PANC-1 pancreatic cancer cells.

Prognostic factors related with survival in patients with pancreatic adenocarcinoma

The prognosis in patients with pancreatic cancer is poor and this cancer is the fourth leading cause of cancer-related death worldwide. Although surgical resection is the only curative treatment of choice for pancreatic cancer, the majority of patients are diagnosed at an advanced stage, thus only 10%-15% of them are suitable for curative resection and the overall survival is less than 5%. Chemotherapy for metastatic disease is to palliate symptoms of patients and to improve survival. Therefore, prognostic factors are important and a correct definition of poor prognostic factors may help to guide more aggressive adjuvant or aggressive treatment protocols in patients with pancreatic cancer. This article reviews the prognostic factors affecting survival of patients with pancreatic cancer in the light of recent advances in the literature.

Gemcitabine-induced pancreatic cancer cell death is associated with MST1/cyclophilin D mitochondrial complexation

The pancreatic adenocarcinoma remains the most aggressive human malignancy with an extremely low 5-year overall survival. Postoperative gemcitabine could significantly delay recurrence after complete resection of pancreatic cancer. However, the underlying mechanisms are not fully understood. The chemo-resistance factors against gemcitabine still need further characterizations. Here we studied the mechanism of gemcitabine-induced pancreatic cancer cell death by focusing on mammalian sterile 20-like kinase 1 (MST1) and cyclophilin D (Cyp-D). We found that MST1 and Cyp-D expressions were significantly lower in gemcitabine-resistant pancreatic cancer tissues and cell lines. In vitro, gemcitabine activated MST1 through reactive oxygen species (ROS) production, which was prevented by antioxidant n-acetyl-cysteine (NAC). We found that gemcitabine-activated MST1 translocated to mitochondria and formed a complex with the local protein Cyp-D. Gemcitabine-induced cell death was alleviated by MST1 or Cyp-D shRNA silencing, but was aggravated by MST1 or Cyp-D over-expression. Further, cyclosporin A (CsA), the Cyp-D inhibitor, prevented gemcitabine-induced MST1/Cyp-D mitochondrial complexation and cancer cell death. We suggest that gemcitabine-induced death of pancreatic cancer cells requires MST1/Cyp-D mitochondrial complexation.

Apoptosis induced by microwave radiation in pancreatic cancer JF305 cells

New therapeutic approaches are needed to improve the survival rate from pancreatic cancer, one of the most lethal human malignancies. In this study, JF305 cells were treated with microwaves at doses of 2.5, 5.0, 10.0, 15.0, and 20.0 mW/cm(2) for 20 min. The inhibition of JF305 cell proliferation was tested using the MTT assay. Apoptotic cells were detected with Hoechst 33258 staining and a Nucleo-Counter NC-3000. The expression of apoptosis-related proteins was examined with Western blot. The results showed that microwaves inhibited the growth of JF305 cells in a dose-dependent manner, and caused morphological changes in apoptotic body formation. The percentages of apoptosis detected using annexin V-fluorescein isothiocyanate (FITC) were 4.0%, 10.0%, 12.0%, and 30.0% with the dosage of microwave (0, 5.0, 10.0, and 20.0 mW/cm(2)), respectively. Treatment with microwaves increased the activity of caspase-9 and caspase-3, down-regulated the expression of Bcl-2, and up-regulated the expression of Bax and CytoC. In addition, the expression level of p65 was increased whereas the level of IκBα down-regulated. Those results suggest that microwaves inhibit cell growth and induce apoptosis in JF305 cells through an NF-κB-regulated mitochondria-mediated pathway.

Transport properties of pancreatic cancer describe gemcitabine delivery and response

BACKGROUND

The therapeutic resistance of pancreatic ductal adenocarcinoma (PDAC) is partly ascribed to ineffective delivery of chemotherapy to cancer cells. We hypothesized that physical properties at vascular, extracellular, and cellular scales influence delivery of and response to gemcitabine-based therapy.

METHODS

We developed a method to measure mass transport properties during routine contrast-enhanced CT scans of individual human PDAC tumors. Additionally, we evaluated gemcitabine infusion during PDAC resection in 12 patients, measuring gemcitabine incorporation into tumor DNA and correlating its uptake with human equilibrative nucleoside transporter (hENT1) levels, stromal reaction, and CT-derived mass transport properties. We also studied associations between CT-derived transport properties and clinical outcomes in patients who received preoperative gemcitabine-based chemoradiotherapy for resectable PDAC.

RESULTS

Transport modeling of 176 CT scans illustrated striking differences in transport properties between normal pancreas and tumor, with a wide array of enhancement profiles. Reflecting the interpatient differences in contrast enhancement, resected tumors exhibited dramatic differences in gemcitabine DNA incorporation, despite similar intravascular pharmacokinetics. Gemcitabine incorporation into tumor DNA was inversely related to CT-derived transport parameters and PDAC stromal score, after accounting for hENT1 levels. Moreover, stromal score directly correlated with CT-derived parameters. Among 110 patients who received preoperative gemcitabine-based chemoradiotherapy, CT-derived parameters correlated with pathological response and survival.

CONCLUSION

Gemcitabine incorporation into tumor DNA is highly variable and correlates with multiscale transport properties that can be derived from routine CT scans. Furthermore, pretherapy CT-derived properties correlate with clinically relevant endpoints.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01276613.

FUNDING

Lustgarten Foundation (989161), Department of Defense (W81XWH-09-1-0212), NIH (U54CA151668, KCA088084).

Perifosine inhibits S6K1-Gli1 signaling and enhances gemcitabine-induced anti-pancreatic cancer efficiency

PURPOSE

The pancreatic cancer has extremely low overall 5-year survival, and gemcitabine is the only approved single agent for pancreatic cancer treatment.

METHODS

In the present study, we investigated the potential effect of perifosine, a novel Akt inhibitor on gemcitabine-induced anti-pancreatic cancer effect both in vivo and in vitro.

RESULTS

We showed that sub-cytotoxic low concentration of perifosine dramatically enhanced gemcitabine-induced cytotoxicity in cultured pancreatic cancer cells. Perifosine inhibited Akt-mammalian target of rapamycin and Erk-mitogen-activated protein kinase activation in pancreatic cancer cells. Meanwhile, perifosine suppressed the hedgehog signaling, as it inhibited glioma-associated oncogenes (Gli) 1 activation and decreased its target protein patched 1 (PTCH1) expression. Our data demonstrated that perifosine blocked p70S6K1 (S6K1) activation, thus disrupting S6K1-Gli1 association and subsequent Gli1 activation. The reduction of S6K1 or Gli1 expression by target siRNAs inhibited PTCH1 expression and enhanced gemcitabine-induced cytotoxicity in pancreatic cancer cells. Significantly, perifosine dramatically enhanced gemcitabine-mediated antitumor effect in a PANC-1 xenograft severe combined immunodeficiency mice model.

CONCLUSIONS

In summary, we conclude that perifosine sensitizes gemcitabine-mediated anti-pancreatic cancer efficiency through regulating multiple signaling pathways.

Impact of reconstruction methods and pathological factors on survival after pancreaticoduodenectomy

Background:

Surgery remains the mainstay of therapy for pancreatic head (PH) and periampullary carcinoma (PC) and provides the only chance of cure. Improvements of surgical technique, increased surgical experience and advances in anesthesia, intensive care and parenteral nutrition have substantially decreased surgical complications and increased survival. We evaluate the effects of reconstruction type, complications and pathological factors on survival and quality of life.

Materials and Methods:

This is a prospective study to evaluate the impact of various reconstruction methods of the pancreatic remnant after pancreaticoduodenectomy and the pathological characteristics of PC patients over 3.5 years. Patient characteristics and descriptive analysis in the three variable methods either with or without stent were compared with Chi-square test. Multivariate analysis was performed with the logistic regression analysis test and multinomial logistic regression analysis test. Survival rate was analyzed by use Kaplan-Meier test.

Results:

Forty-one consecutive patients with PC were enrolled. There were 23 men (56.1%) and 18 women (43.9%), with a median age of 56 years (16 to 70 years). There were 24 cases of PH cancer, eight cases of PC, four cases of distal CBD cancer and five cases of duodenal carcinoma. Nine patients underwent duct-to-mucosa pancreatico jejunostomy (PJ), 17 patients underwent telescoping pancreatico jejunostomy (PJ) and 15 patients pancreaticogastrostomy (PG). The pancreatic duct was stented in 30 patients while in 11 patients, the duct was not stented. The PJ duct-to-mucosa caused significantly less leakage, but longer operative and reconstructive times. Telescoping PJ was associated with the shortest hospital stay. There were 5 postoperative mortalities, while postoperative morbidities included pancreatic fistula-6 patients, delayed gastric emptying in-11, GI fistula-3, wound infection-12, burst abdomen-6 and pulmonary infection-2. Factors that predisposed to development of pancreatic leakage included male gender, preoperative albumin < 30g/dl, pre-operative hemoglobin < 10g/dl and non PJ-duct to mucosa type of reconstruction. The ampullary cancers presented at an earlier stage and had a better prognosis than pancreatic cancer and cholangiocarcinoma. Early stage (I and II), negative surgical margin, well and moderate differentiation and absence of lymph node involvement significantly predicted for longer survival.

Conclusions:

PJ duct-to-mucosa anastomosis was safe, caused least pancreatic leakage and least blood loss compared with the other methods of reconstruction and was associated with early return back to home and prolonged disease free and overall survival.

Ron knockdown and Ron monoclonal antibody IMC-RON8 sensitize pancreatic cancer to histone deacetylase inhibitors (HDACi)

Recepteur d'origine nantais (Ron) is overexpressed in a panel of pancreatic cancer cells and tissue samples from pancreatic cancer patients. Ron can be activated by its ligand macrophage stimulating protein (MSP), thereby activating oncogenic signaling pathways. Crosstalk between Ron and EGFR, c-Met, or IGF-1R may provide a mechanism underlying drug resistance. Thus, targeting Ron may represent a novel therapeutic strategy. IMC-RON8 is the first Ron monoclonal antibody (mAb) entering clinical trial for targeting Ron overexpression. Our studies show IMC-RON8 downmodulated Ron expression in pancreatic cancer cells and significantly blocked MSP-stimulated Ron activation, downstream Akt and ERK phosphorylation, and survivin mRNA expression. IMC-RON8 hindered MSP-induced cell migration and reduced cell transformation. Histone deacetylase inhibitors (HDACi) are reported to target expression of various genes through modification of nucleosome histones and non-histone proteins. Our work shows HDACi TSA and Panobinostat (PS) decreased Ron mRNA and protein expression in pancreatic cancer cells. PS also reduced downstream signaling of pAkt, survivin, and XIAP, as well as enhanced cell apoptosis. Interestingly, PS reduced colony formation in Ron knockdown cells to a greater extent than Ron scramble control cells in colony formation and soft agarose assays. IMC-RON8 could also sensitize pancreatic cancer cells to PS, as reflected by reduced colony numbers and size in combination treatment with IMC-RON8 and PS compared to single treatment alone. The co-treatment further reduced Ron expression and pAkt, and increased PARP cleavage compared to either treatment alone. This study suggests the potential for a novel combination approach which may ultimately be of value in treatment of pancreatic cancer.

Putative predictive biomarkers of survival in patients with metastatic pancreatic adenocarcinoma treated with gemcitabine and ganitumab, an IGF1R inhibitor

PURPOSE

This planned exploratory analysis assessed the predictive nature of baseline circulating factors of the insulin-like growth factor (IGF) axis on the treatment effect of ganitumab (monoclonal antibody inhibitor of IGF-1 receptor) plus gemcitabine in a randomized phase II study in metastatic pancreatic adenocarcinoma.

EXPERIMENTAL DESIGN

Baseline levels of IGFs/IGF binding proteins (IGFBP) were analyzed in serum or plasma. Mutations and gene expression were analyzed in archival samples. Treatment effects between biomarker subgroups were compared for overall survival (OS). Associations of tumor markers with OS were evaluated.

RESULTS

For patients with evaluable samples, ganitumab was associated with improved OS versus placebo (HR, 0.49; 95% CI: 0.28-0.87). The treatment effect on improved OS was strong in the patient subset with higher levels of IGF-1, IGF-2, or IGFBP-3, or lower levels of IGFBP-2, but not so on the other corresponding subset. Median OS of ganitumab versus placebo in patients with higher levels of IGF-1, IGF-2, and IGFBP-3 was 16 versus 6.8 months (HR, 0.25; 95% CI: 0.09-0.67), 16 versus 5.9 months (HR, 0.24; 95% CI: 0.09-0.68), and 16 versus 6.8 months (HR, 0.28; 95% CI: 0.11-0.73), and in patients with lower IGFBP-2 levels was 12.7 versus 6.6 months (HR, 0.19; 95% CI: 0.07-0.55). Interaction between treatment and IGFs/IGFBPs in multivariate analyses suggested predictive potential for IGF-2 (P = 0.002) and IGFBP-2 (P = 0.02). KRAS mutation status and PTEN expression were not associated with OS.

CONCLUSIONS

Baseline circulating factors of the IGF axis may predict OS benefit from ganitumab plus gemcitabine in metastatic pancreatic adenocarcinoma.

CIP2A expression is associated with altered expression of epithelial-mesenchymal transition markers and predictive of poor prognosis in pancreatic ductal adenocarcinoma

CIP2A has been regarded as a novel potential therapeutic target for multiple cancers. The aim of this study was to detect CIP2A expression in pancreatic ductal adenocarcinoma (PDA) and to analyze its association with prognosis of PDA patients. The expression of CIP2A and three epithelial-mesenchymal transition (EMT)-related proteins (E-cadherin, N-cadherin, and vimentin) was examined in 96 PDA tissue samples by immunohistochemistry. Fifty-four cases (56.3 %) were defined as positive for CIP2A expression. Immunohistochemistry showed that CIP2A expression was correlated with poor tumor differentiation, TNM stage, and lymph node metastasis. Kaplan-Meier survival analysis showed that patients with CIP2A-positive expression showed lower overall survival rate than those with CIP2A-negative expression. Multivariate analysis showed that CIP2A expression was an independent prognostic factor for PDA patients. Furthermore, positive expression of CIP2A was strongly associated with loss of the epithelial marker E-cadherin and acquisition of the expression of the mesenchymal markers N-cadherin and vimentin. These findings suggest that CIP2A might promote EMT and progression in PDA, and thus may be a potential therapeutic target for patients with PDA.

Caffeic Acid phenethyl ester inhibits epithelial-mesenchymal transition of human pancreatic cancer cells

Background. This study aimed to investigate the effect of propolis component caffeic acid phenethyl ester (CAPE) on epithelial-mesenchymal transition (EMT) of human pancreatic cancer cells and the molecular mechanisms underlying these effects. Methods. The transforming growth factor β (TGF-β-) induced EMT in human pancreatic PANC-1 cancer cells was characterized by observation of morphology and the expression of E-cadherin and vimentin by western blotting. The migration potential was estimated with wound closure assay. The expression of transcriptional factors was measured by quantitative RT-PCR and immunocytochemistry staining. The orthotopic pancreatic cancer xenograft model was used for in vivo assessment. Results. The overexpression of vimentin was attenuated by CAPE, and the alteration in morphology from polygonal to spindle shape was partially reversed by CAPE. Furthermore, CAPE delayed the TGF-β-stimulated migration potential. CAPE treatment did not reduce the expression levels of Smad 2/3, Snail 1, and Zeb 1 but inhibited the expression of transcriptional factor Twist 2. By using an orthotopic pancreatic cancer model, CAPE suppressed the expression of Twist 2 and growth of PANC-1 xenografts without significant toxicity. Conclusion. CAPE could inhibit the orthotopic growth and EMT of pancreatic cancer PANC-1 cells accompanied by downregulation of vimentin and Twist 2 expression.

Aberrant glycogen synthase kinase 3β in the development of pancreatic cancer

Development and progression of pancreatic cancer involves general metabolic disorder, local chronic inflammation, and multistep activation of distinct oncogenic molecular pathways. These pathologic processes result in a highly invasive and metastatic tumor phenotype that is a major obstacle to curative surgical intervention, infusional gemcitabine-based chemotherapy, and radiation therapy. Many clinical trials with chemical compounds and therapeutic antibodies targeting growth factors, angiogenic factors, and matrix metalloproteinases have failed to demonstrate definitive therapeutic benefits to refractory pancreatic cancer patients. Glycogen synthase kinase 3β (GSK3β), a serine/threonine protein kinase, has emerged as a therapeutic target in common chronic and progressive diseases, including cancer. Here we review accumulating evidence for a pathologic role of GSK3β in promoting tumor cell survival, proliferation, invasion, and resistance to chemotherapy and radiation in pancreatic cancer. We also discuss the putative involvement of GSK3β in mediating metabolic disorder, local inflammation, and molecular alteration leading to pancreatic cancer development. Taken together, we highlight potential therapeutic as well as preventive effects of GSK3β inhibition in pancreatic cancer.

Radiofrequency ablation of liver metastasis in patients with locally controlled pancreatic ductal adenocarcinoma

PURPOSE

To evaluate retrospectively the role of radiofrequency (RF) ablation for liver metastases arising from pancreatic ductal adenocarcinoma simultaneously with pancreatic resection or after curative resection in patient survival.

MATERIALS AND METHODS

RF ablation of liver metastases was performed on 34 patients with pancreatic ductal adenocarcinoma postoperatively after pancreatectomy or intraoperatively at pancreatectomy between December 2002 and June 2009. Criteria for RF ablation were liver metastasis ≤ 3 cm diameter in size, five or fewer lesions, and no definite suspicious lesion other than liver metastasis. Patient survival was assessed by the Kaplan-Meier method, and prognostic factors were analyzed.

RESULTS

Of the patients receiving RF ablation treatment (n = 34), 18 underwent one session of RF ablation, and 16 underwent more than one session. In each session, all the targeted lesions were successfully ablated by ultrasound-guided RF ablation. Median duration of follow-up was 15 months (range, 3-65 mo). The interval between pancreatic resection and liver metastasis was 3 months (range, 0-33 mo). Median survival time after liver metastasis was 14 months. Univariate analysis of factors affecting survival showed that better patient survival after RF ablation was associated with a single, < 2 cm diameter liver metastasis (P = .007) and well or moderate differentiation (P = .032). In multivariate analysis, a single < 2 cm diameter liver metastasis and good or moderate differentiation were independent predictors for longer patient survival (P = .027, P = .016).

CONCLUSIONS

RF ablation in liver metastasis occurring after locally controlled pancreatic ductal adenocarcinoma can be a safe and feasible strategy for extending survival in selected patients.

Mucin-based targeted pancreatic cancer therapy

The prognosis of pancreatic cancer (PC) patients is very poor with a five-year survival of less than 5%. One of the major challenges in developing new therapies for PC is the lack of expression of specific markers by pancreatic tumor cells. Mucins are heavily Oglycosylated proteins characterized by the presence of short stretches of amino acid sequences repeated several times in tandem. The expression of several mucins including MUC1, MUC4, MUC5AC, and MUC16 is strongly upregulated in PC. Recent studies have also demonstrated a link between the aberrant expression and differential overexpression of mucin glycoproteins to the initiation, progression, and poor prognosis of the disease. These studies have led to increasing recognition of mucins as potential diagnostic markers and therapeutic targets in PC. In this focused review we present an overview of the therapies targeting mucins in PC, including immunotherapy (i.e. vaccines, antibodies, and radioimmunoconjugates), gene therapy, and other novel therapeutic strategies.

Clinical significance of clusterin expression in pancreatic adenocarcinoma

BACKGROUND

Clusterin is known to be expressed in many human neoplasms, and is believed to participate in the regeneration, migration, and anti-apoptosis of tumor cells. However, few reports have addressed the relationship between the manifestation of clusterin and clinicopathologic parameters in pancreas cancer patients. In the present study, the authors investigated the expression of clusterin and its clinical significance in pancreatic adenocarcinoma.

METHODS

Immunohistochemical staining was performed for clusterin in tumor tissues obtained from patients who received pancreatic resection with radical intent, and the associations of clusterin expression with various clinicopathologic parameters were analyzed in addition to the relation between its expression and survival.

RESULTS

Immunoreactivity for clusterin was observed in 17 of the 52 (33%) pancreatic adenocarcinomas examined. In addition, clusterin positivity was found to be associated with preoperative serum carcinoembryonic antigen level, perineural invasion, and, most strongly, lymph node metastasis. The survival analysis identified tumor differentiation and lymph node metastasis as the only significant prognostic factors.

CONCLUSION

Although not an independent prognostic factor, clusterin immunoreactivity can be used in conjunction with lymph node metastasis to predict survival in cases of pancreatic adenocarcinoma.

Evaluation of a gene-directed enzyme-product therapy (GDEPT) in human pancreatic tumor cells and their use as in vivo models for pancreatic cancer

Background

Gene-directed enzyme prodrug therapy (GDEPT) is a two-step treatment protocol for solid tumors that involves the transfer of a gene encoding a prodrug-activating enzyme followed by administration of the inactive prodrug that is subsequently activated by the enzyme to its tumor toxic form. However, the establishment of such novel treatment regimes to combat pancreatic cancer requires defined and robust animal model systems.

Methods

Here, we comprehensively compared six human pancreatic cancer cell lines (PaCa-44, PANC-1, MIA PaCa-2, Hs-766T, Capan-2, and BxPc-3) in subcutaneous and orthotopical mouse models as well as in their susceptibility to different GDEPTs.

Results

Tumor uptake was 83% to 100% in the subcutaneous model and 60% to 100% in the orthotopical mouse model, except for Hs-766T cells, which did not grow orthotopically. Pathohistological analyses of the orthotopical models revealed an infiltrative growth of almost all tumors into the pancreas; however, the different cell lines gave rise to tumors with different morphological characteristics. All of the resultant tumors were positive for MUC-1 staining indicating their origin from glandular or ductal epithelium, but revealed scattered pan-cytokeratin staining. Transfer of the cytochrome P450 and cytosine deaminase suicide gene, respectively, into the pancreatic cancer cell lines using retroviral vector technology revealed high level infectibility of these cell lines and allowed the analysis of the sensitivity of these cells to the chemotherapeutic drugs ifosfamide and 5-fluorocytosine, respectively.

Conclusion

These data qualify the cell lines as part of valuable in vitro and in vivo models for the use in defined preclinical studies for pancreas tumor therapy.

Experimental in vivo and in vitro treatment with a new histone deacetylase inhibitor belinostat inhibits the growth of pancreatic cancer

Background

Treatment options for pancreatic ductal adenocarcinoma (PDAC) are limited. Histone deacetylase inhibitors are a new and promising drug family with strong anticancer activity. The aim of this study was to examine the efficacy of in vitro and in vivo treatment with the novel pan-HDAC inhibitor belinostat on the growth of human PDAC cells.

Methods

The proliferation of tumour cell lines (T3M4, AsPC-1 and Panc-1) was determined using an MTT assay. Apoptosis was analysed using flow cytometry. Furthermore, p21^Cip1/Waf1 and acetylated histone H4 (acH4) expression were confirmed by immunoblot analysis. The in vivo effect of belinostat was studied in a chimeric mouse model. Antitumoural activity was assessed by immunohistochemistry for Ki-67.

Results

Treatment with belinostat resulted in significant in vitro and in vivo growth inhibition of PDAC cells. This was associated with a dose-dependent induction of tumour cell apoptosis. The apoptotic effect of gemcitabine was further enhanced by belinostat. Moreover, treatment with belinostat increased expression of the cell cycle regulator p21^Cip1/Waf1 in Panc-1, and of acH4 in all cell lines tested. The reductions in xenograft tumour volumes were associated with inhibition of cell proliferation.

Conclusion

Experimental treatment of human PDAC cells with belinostat is effective in vitro and in vivo and may enhance the efficacy of gemcitabine. A consecutive study of belinostat in pancreatic cancer patients alone, and in combination with gemcitabine, could further clarify these effects in the clinical setting.