Vandetanib plus gemcitabine versus placebo plus gemcitabine in locally advanced or metastatic pancreatic carcinoma (ViP): a prospective, randomised, double-blind, multicentre phase 2 trial

Alantolactone induces apoptosis and improves chemosensitivity of pancreatic cancer cells by impairment of autophagy-lysosome pathway via targeting TFEB

The lysosome is emerging as a central regulator of the autophagic process, which plays a critical role in tumor growth and chemoresistance. Alantolactone, which is a natural compound produced by Inula helenium, has been shown to induce apoptosis in numerous cancer types. However, the mechanism by which alantolactone regulates apoptosis is still poorly understood. In this work, we observed that alantolactone caused the accumulation of autophagosomes due to impaired autophagic degradation and substantially inhibited the activity and expression of CTSB/CTSD proteins that when depleted caused lysosomal dysfunction. Furthermore, we found that alantolactone inhibited the proliferation of pancreatic cancer cells in vitro and in vivo and enhanced the chemosensitivity of pancreatic cancer cells to oxaliplatin. In addition, a reduction in TFEB levels was a critical event in the apoptosis and cell death caused by alantolactone. Our data demonstrated that alantolactone, which impaired autophagic degradation, was a pharmacological inhibitor of autophagy in pancreatic cancer cells and markedly enhanced the chemosensitivity of pancreatic cancer cells to oxaliplatin.

WAVE3 promotes proliferation, migration and invasion via the AKT pathway in pancreatic cancer

Alterations in Wiskott-Aldrich syndrome protein family verprolinhomologous protein 3 (WAVE3) expression play various roles in certain types of cancer. However, the roles of WAVE3 expression in pancreatic cancer remain unknown. The present retrospective study demonstrated that WAVE3 expression was higher in cancerous pancreatic tissues than in non-neoplastic tissues. Moreover, WAVE3 overexpression was related to lymphatic metastasis, a poor differentiation and high pre-operative CA19-9 levels and was an adverse prognostic factor for patients with pancreatic cancer. In vitro, the knockdown of WAVE3 inhibited the proliferative, migratory and invasive potential of pancreatic cancer cells and promoted cell apoptosis. Western blot analysis demonstrated that WAVE3 influenced the protein kinase B (PBK/AKT) pathway by suppressing the expression of pyruvate dehydrogenase kinase isoform 2 (PDK2) and then negatively inhibiting the phosphorylation of Ser473 on AKT. Furthermore, the expression of AKT pathway downstream proteins [certain epithelial-mesenchymal transition (EMT)-related proteins, p53, Bcl-2 and cyclin D1] was accordingly altered. Taken together, our findings suggest that WAVE3 influences cell proliferation, migration and invasion via the AKT pathway, and targeting WAVE3 and/or the AKT pathway may potentially serve as a treatment strategy for pancreatic cancer.

Identification of genes highly downregulated in pancreatic cancer through a meta-analysis of microarray datasets: implications for discovery of novel tumor-suppressor genes and therapeutic targets

PURPOSE

The lack of specific symptoms at early tumor stages, together with a high biological aggressiveness of the tumor contribute to the high mortality rate for pancreatic cancer (PC), which has a 5-year survival rate of about 7%. Recent failures of targeted therapies inhibiting kinase activity in clinical trials have highlighted the need for new approaches towards combating this deadly disease.

METHODS

In this study, we have identified genes that are significantly downregulated in PC, through a meta-analysis of large number of microarray datasets. We have used qRT-PCR to confirm the downregulation of selected genes in a panel of PC cell lines.

RESULTS

This study has yielded several novel candidate tumor-suppressor genes (TSGs) including GNMT, CEL, PLA2G1B and SERPINI2. We highlight the role of GNMT, a methyl transferase associated with the methylation potential of the cell, and CEL, a lipase, as potential therapeutic targets. We have uncovered genetic links to risk factors associated with PC such as smoking and obesity. Genes important for patient survival and prognosis are also discussed, and we confirm the dysregulation of metabolic pathways previously observed in PC.

CONCLUSIONS

While many of the genes downregulated in our dataset are associated with protein products normally produced by the pancreas for excretion, we have uncovered some genes whose downregulation appear to play a more causal role in PC. These genes will assist in providing a better understanding of the disease etiology of PC, and in the search for new therapeutic targets and biomarkers.

Advances in Molecular Profiling and Categorisation of Pancreatic Adenocarcinoma and the Implications for Therapy

Pancreatic ductal adenocarcinoma (PDAC) continues to be a disease with poor outcomes and short-lived treatment responses. New information is emerging from genome sequencing identifying potential subgroups based on somatic and germline mutations. A variety of different mutations and mutational signatures have been identified; the driver mutation in around 93% of PDAC is KRAS, with other recorded alterations being SMAD4 and CDKN2A. Mutations in the deoxyribonucleic acid (DNA) damage repair pathway have also been investigated in PDAC and multiple clinical trials are ongoing with DNA-damaging agents. Rare mutations in BRAF and microsatellite instability (MSI) have been reported in about 1-3% of patients with PDAC, and agents used in other cancers to target these have also shown some promise. Immunotherapy is a developing field, but has failed to demonstrate benefits in PDAC to date. While many trials have failed to improve outcomes in this deadly disease, there is optimism that by developing a better understanding of the translational aspects of this cancer, future informed therapeutic strategies may prove more successful.

Thymidylate synthase prompts metastatic progression through the dTMP associated EMT process in pancreatic ductal adenocarcinoma

As a fundamental metabolic enzyme, anti-Thymidylate synthase (TS) strategy has been shown to be an effective therapy for human cancers. However, the genuine effects of TS in pancreatic ductal adenocarcinoma (PDA) are still conflicting. We systemically assessed the prognostic value and whether TS associated with malignant progression in PDA. Protein and mRNA expression level of TS were evaluated in en bloc PDA samples, the prognostic effect of TS expressed in cytoplasm or cytonuclear was determined separately in the first time. The impact of TS on tumor cell behaviors was assessed in in vitro assays, and the TS associated metastatic potential was further determined in two different PDA metastatic models. The retrospective clinical analysis firstly demonstrated that tumor cytonuclear TS expression was positively correlated with lymphatic metastasis and negatively correlated with the overall survival (OS) in PDA patients. The subsequent experiments further confirmed that TS depletion can effectively abate EMT (epithelial to mesenchymal) process in in vitro and decline most of the metastatic lesions in two different PDA mice models, and the deoxythymidine monophosphate (dTMP) biosynthesis malfunction resulted imbalanced dNTP pools may be the fundamental causation. Collectively, the present study suggested the prospective strategy of combined anti-TS scheme for metastatic PDA, and we strongly suggest further clinical standardization research with a large cohort to verify the prognostic value and the therapeutic potential of TS in PDA.

Pancreatic Cancer: Molecular Characterization, Clonal Evolution and Cancer Stem Cells

Pancreatic Ductal Adenocarcinoma (PDAC) is the fourth most common cause of cancer-related death and is the most lethal of common malignancies with a five-year survival rate of <10%. PDAC arises from different types of non-invasive precursor lesions: intraductal papillary mucinous neoplasms, mucinous cystic neoplasms and pancreatic intraepithelial neoplasia. The genetic landscape of PDAC is characterized by the presence of four frequently-mutated genes: KRAS, CDKN2A, TP53 and SMAD4. The development of mouse models of PDAC has greatly contributed to the understanding of the molecular and cellular mechanisms through which driver genes contribute to pancreatic cancer development. Particularly, oncogenic KRAS-driven genetically-engineered mouse models that phenotypically and genetically recapitulate human pancreatic cancer have clarified the mechanisms through which various mutated genes act in neoplasia induction and progression and have led to identifying the possible cellular origin of these neoplasias. Patient-derived xenografts are increasingly used for preclinical studies and for the development of personalized medicine strategies. The studies of the purification and characterization of pancreatic cancer stem cells have suggested that a minority cell population is responsible for initiation and maintenance of pancreatic adenocarcinomas. The study of these cells could contribute to the identification and clinical development of more efficacious drug treatments.

Extraordinary response of metastatic pancreatic cancer to apatinib after failed chemotherapy: A case report and literature review

Chemotherapy has limited efficacy in the treatment of advanced and metastatic pancreatic cancer (PC), and has serious side effects. The development of novel effective agents, especially targeted therapy, is essential for patients with PC. We present a 58-year-old Chinese woman initially diagnosed with locally advanced PC. As the disease progressed to Stage IV, the patient was unable to tolerate chemotherapy after the fourth-line treatment. She was then treated with apatinib, a novel and highly selective tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2 and achieved a progression-free-survival of 7 mo. All drug-related side effects were well controlled with medication. To the best of our knowledge, this is the first case of PC which responded to apatinib. Considering this remarkable response, apatinib may be a promising agent in the treatment of PC. We also reviewed the literature on chemotherapy and targeted therapy, especially the anti-angiogenesis therapy for patients with PC, and investigated the effect of apatinib in other solid tumors as well.