Search

Background: The molecular signature underlying pancreatic ductal adenocarcinoma (PDAC) progression may include key proteins affecting the malignant phenotypes. Here, we aimed to identify the proteins implicated in PDAC with different tumour-node-metastasis (TNM) stages., Methods: Eight-plex isobaric tags coupled with two-dimensional liquid chromatography-tandem mass spectrometry were used to analyse the proteome of PDAC tissues with different TNM stages. A loss-of-function study was performed to evaluate the oncogenic roles of WD repeat-containing protein 1 (WDR1) in PDAC. The molecular mechanism by which WDR1 promotes PDAC progression was studied by real-time qPCR, Western blotting, proximity ligation assay and co-immunoprecipitation., Results: A total of 5036 proteins were identified, and 4708 proteins were quantified with high confidence. Compared with normal pancreatic tissues, 37 proteins were changed significantly in PDAC tissues of different stages. Moreover, 64 proteins were upregulated or downregulated in a stepwise manner as the TNM stages of PDAC increased, and 10 proteins were related to tumorigenesis. The functionally uncharacterised protein, WDR1, was highly expressed in PDAC and predicted a poor prognosis. WDR1 knockdown suppressed PDAC tumour growth and metastasis in vitro and in vivo. Moreover, WDR1 knockdown repressed the activity of the Wnt/β-Catenin pathway; ectopic expression of a stabilised form of β-Catenin restored the suppressive effects of WDR1 knockdown. Mechanistically, WDR1 interacted with USP7 to prevent ubiquitination-mediated degradation of β-Catenin., Conclusion: Our study identifies several previous functional unknown proteins implicated in the progression of PDAC, and provides new insight into the oncogenic roles of WDR1 in PDAC development.

Immobilization of a ligand that selectively interacts with cancer cells to nanomaterials can enhance their diagnostic and therapeutic efficiency. In this study, we firstly demonstrate the high expression of receptor for cyclic nine-amino acid peptide LyP-1 (Cys-Gly-Asn-Lys-Arg-Thr-Arg-Gly-Cys) in both mouse and human pancreatic cancer. Based on these findings, sub-50 nm multifunctional superparamagnetic mesoporous nanospheres with surface modified with LyP-1 are rationally designed. Theses nanospheres have a core of silica-protected magnetite nanoparticle and a shell of FITC-labeled mesoporous silica, and they are able to specifically recognize and conjugate with the pancreatic cancer cell in vitro, as verified by the combined techniques of fluorescent imaging and T2 weight magnetic resonance imaging. After systematic administration, these LyP-1 immobilized nanospheres are found to actively target to mouse orthotopic xenograft of pancreatic cancer, which opens up the door for applications in early probing and diagnosis of pancreatic cancer by the multimodal imaging., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Pancreatic cancer (PC) remains difficult to treat, despite the recent advances in various anticancer therapies. Immuno-inflammatory response is considered to be a major risk factor for the development of PC in addition to a combination of genetic background and environmental factors. Although patients with PC exhibit evidence of systemic immune dysfunction, the PC microenvironment is replete with immune cells., Methods: We searched PubMed for all relevant English language articles published up to March 2016. They included clinical trials, experimental studies, observational studies, and reviews. Trials enrolled at Clinical trial.gov were also searched., Results: PC induces an immunosuppressive microenvironment, and intratumoral activation of immunity in PC is attenuated by inhibitory signals that limit immune effector function. Multiple types of immune responses can promote an immunosuppressive microenvironment; key regulators of the host tumor immune response are dendritic cells, natural killer cells, macrophages, myeloid derived suppressor cells, and T cells. The function of these immune cells in PC is also influenced by chemotherapeutic agents and the components in tumor microenvironment such as pancreatic stellate cells. Immunotherapy of PC employs monoclonal antibodies/effector cells generated in vitro or vaccination to stimulate antitumor response. Immune therapy in PC has failed to improve overall survival; however, combination therapies comprising immune checkpoint inhibitors and vaccines have been attempted to increase the response., Conclusion: A number of studies have begun to elucidate the roles of immune cell subtypes and their capacity to function or dysfunction in the tumor microenvironment of PC. It will not be long before immune therapy for PC becomes a clinical reality., Competing Interests: The authors have no conflicts of interest to disclose.

Objective: To determine if the density of FOXP3+ lymphocytes in primary tumors and lymph nodes in pancreatic cancer correlates with the presence of lymph node metastases., Methods: FOXP3+ lymphocyte density in primary pancreatic cancer tissue and draining lymph nodes was measured using immunohistochemistry. We analyzed the clinical and pathological aspects associated with the accumulation of FOXP3+ lymphocytes in pancreatic cancer. We also analyzed the correlation of density of FOXP3+ lymphocytes in lymph nodes with the nodal status and distance from the primary tumor., Results: FOXP3+ lymphocyte density in pancreatic cancer was significantly higher than in paratumoral pancreatic tissue. The density of FOXP3+ lymphocytes in local tumor tissue correlated significantly with the histological grade and overall lymph node status. Furthermore, FOXP3+ lymphocyte density was significantly higher in positive lymph nodes than in negative ones, while it had no correlation with the distance of the lymph node from the primary tumor., Conclusion: FOXP3+ lymphocyte density in primary tumor tissue in patients with pancreatic cancer correlates with lymph node metastasis. Lymph nodes containing metastases having higher FOXP3+ lymphocyte densities than do negative lymph nodes.

Pancreatic cancer is known for its bad prognosis. Micro-RNAs mis-expressions are associated with various human cancers and offer new candidate targets for diagnostic and therapeutic strategies. Micro-RNA-222 has been shown to play a crucial role in cancer cell proliferation in recent studies. However, its correlations with the clinicopathological characters of pancreatic cancer still remain unclear. Through a prospective study of 60 pairs of pancreatic cancer tissues, adjacent normal tissues were examined by quantitative reverse-transcription polymerase chain reaction. The correlation between the expression of micro-RNA-222 and clinico-pathological characters was performed using the two-sample Student's t test. The survival correlations were analyzed by the Kaplan-Meier method and the Cox's proportional hazards model. Results showed that the expression levels of micro-RNA-222 were significantly elevated in the pancreatic cancer tissue compared with that in adjacent normal tissue. In addition, the overexpression of the tissue micro-RNA-222 strongly related to the expression level of Ki67. Finally, Cox's proportional hazards model analysis confirmed that micro-RNA-222 high expression level was an independent predictor of poor prognosis. This study provides the first evidence of a potential link between Ki67 and micro-RNA-222, which are both relevant to cell proliferation. Our data suggest the potential of micro-RNA-222 as a prognostic biomarker for the pancreatic cancer.

Pancreatic cancer is known for its poor prognosis and early lymphatic metastasis is a notable characteristic. microRNAs (miRNAs) have been shown to be involved in the initiation and progression of pancreatic cancer. We, therefore, established a screening strategy to find miRNAs related to the lymphatic metastasis of pancreatic cancer and explored the target genes of miRNAs. miRNA array profiles were analyzed in tissue samples [pancreatic ductal adenocarcinoma (PDAC) and matched adjacent benign tissues (MAT)] and cell lines (BxPC-3-LN and BxPC-3). Combined analysis of profiling data from tissue samples and cell lines was used to identify miRNAs related to the lymphatic metastasis of pancreatic cancer. The expression levels of miRNAs were confirmed by real‑time reverse transcription PCR (RT-PCR) in tissue samples and cell lines. The correlation between miRNAs and clinicopathological characteristics was investigated. The expression features of miRNAs in pancreatic cancer, precursor lesions and metastatic lymph nodes were characterized by in situ hybridization (ISH). Predicted target genes of miRNAs were validated by RT-PCR and the protein levels of target genes were revealed by western blotting. Seventy and 63 miRNAs were differentially expressed in pancreatic cancer and BxPC-3-LN, compared to MAT and BxPC-3, respectively. Combined microarray analysis found 4 co-differentially expressed miRNAs (miRNA-663, miRNA-145, miRNA-218 and let-7) related to the lymphatic metastasis of pancreatic cancer. miRNA-218 was significantly downregulated in BxPC-3-LN (fold-change>10) and the expression levels of miRNA-218 were confirmed by RT-PCR. The group with lymph node metastasis and the elder group (age>64) showed lower expression of miRNA-218 (P=0.003 and 0.002), compared to patients without lymph nodes metastasis and patients in the younger group (age≤64), respectively. The expression of miRNA‑218 showed a decreasing trend from normal acinar/ductal epithelium, intraductal papillary mucinous neoplasm (IPMN), pancreatic cancer to metastatic lymph nodes by ISH. Among 8 predicted target genes of miRNA-218, rodent bone (ROBO-1) was confirmed to be upregulated in both mRNA and protein levels in pancreatic cancer. In conclusion, we established a screening strategy based on microarray results and found miRNA-218 to be a notable gene related to lymphatic metastasis of pancreatic cancer. Downregulation of miRNA-218 and upregulation of ROBO-1 were first demonstrated in pancreatic cancer. The miRNA-218 and ROBO-1 signaling axis may contribute to the lymphatic metastasis of pancreatic cancer.

Pancreatic cancer is a devastating disease with incidence increasing at an alarming rate and survival not improved substantially during the past three decades. Although enormous efforts have been made in early detection and comprehensive treatment for this disease, little or no survival improvement was obtained, which necessitates the development of novel strategies. Emerging inorganic nanomaterials, such as carbon nanotubes, quantum dots, mesoporous silica/gold/supermagnetic nanoparticles, have been widely used in biomedical research with great optimism for cancer diagnosis and therapy. Such nanoparticles possess unique optical, electrical, magnetic and/or electrochemical properties. With such properties along with their impressive nano-size, these particles can be targeted to cancer cells, tissues, and ligands efficiently and monitored with extreme precision in real-time. In additional to liposome, dendrimer, and polymeric nanoparticles, they are considered the most promising nanomaterials with the capability of both cancer detection and multimodality treatment. Emerging approaches to harness nanotechnology to optimize the existing diagnostic and therapeutic tools for pancreatic cancer have been extensively explored during the recent years. Future options for early detection, individual therapy and monitoring responses of pancreatic cancer are focused on multifunctional nanomedicine. In this review, we present the recent development of clinically applicable inorganic nanoparticles, with focus on the diagnosis and treatment of pancreatic cancer. Furthermore, their advantages in theranostic nanomedicine, and challenges of translation to clinical practice, are discussed., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Despite rapid advances in cancer diagnosis and treatment, pancreatic cancer remains one of the most difficult human malignancies to be treated, with a mortality rate nearly equal to its incidence. Although gemcitabine has been established as the standard first-line treatment for advanced pancreatic cancer, gemcitabine-based combination chemotherapy showed either marginal or no improvement in survival. Developments in liposomal delivery systems have facilitated the targeting of specific agents for cancer treatment. Such systems could be developed as platforms for future multi-functional theranostic nanodevices tailor-made for the combined detection of early cancer and functional drug delivery. We systemically review liposome based drug-delivery systems, which can provide improved pharmacokinetics, reduced side effects and potentially increased tumor uptake, for pancreatic cancer therapy. Novel liposomal formulations allowing for higher tumor targeting efficiencies and used in current clinical trials to treat this challenging disease are emphasized., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Strategies using carbon-based nanomaterials as carriers for delivering chemotherapeutic drugs to cancers have been described well. Here a novel magnetic lymphatic-targeting drug-delivery system, based on functionalised carbon nanotubes (fCNTs), is presented with the aim of improving the outcome of cancer with lymph node involvement. The potential therapeutic effect of gemcitabine (GEM) loading magnetic multiwalled carbon nanotubes (mMWNTs) was compared with that of GEM loading magnetic-activated carbon particles (mACs) in vitro and in vivo. mMWNTs-GEM and mACs-GEM both had high anti-tumour activity in vitro similar to free drug. Subcutaneous administration of GEM loading magnetic nanoparticles resulted in successful regression and inhibition of lymph node metastasis under the magnetic field, with mMWNTs-GEM superior to mACs-GEM, and more effectively in the high-dose versus low-dose groups. The successful application of intra-lymphatic delivery of chemotherapeutics using mMWNTs highlights the clinical potential of fCNTs for future cancer metastasis treatment with high efficacy and minimum side-effects., (Copyright © 2011 Elsevier Ltd. All rights reserved.)