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Pancreatic ductal adenocarcinoma (PDAC) is currently the third leading cause of cancer-related deaths and has a 5-year survival rate of less than 10%, far below the ~70% national average for all cancers. This poor prognosis is driven by an extreme resistance to nearly all known cancer treatments, which has long been attributed to hypoxia driven interactions between tumor cells and the supporting stromal microenvironment. The cellular response to hypoxia is driven by the transcription factors known as the hypoxia inducible factors (HIFs), which have been hypothesized to play a role in the pathobiology of PDAC as well as a potential therapeutic target based on years of cell culture data. Attempts to validate the oncogenic role of HIF in PDAC through rigorous spontaneous tumor models have paradoxically shown that the HIFs may act as a tumor suppressor in epithelial cells. Here, we seek to resolve this paradox by discussing the roles of HIFs both in cancer cells and the supporting microenvironment and place them into context of current model systems that could be used to interrogate these interactions. We suggest that HIF may exert its oncogenic influences by modulating the form and function of the stroma rather than direct effects on cancer cells. [ABSTRACT FROM AUTHOR]

The identification of circulating tumor cells (CTCs) relies on epithelial tumor cell markers. In the present study, we aimed to determine whether cell-surface vimentin could be a biomarker to isolate CTCs in pancreatic ductal adenocarcinoma (PDAC). Vimentin was identified as highly expressed on the surface of mesenchymal-phenotype pancreatic tumor cells. Vimentin+ CTCs were detected in 76% of patients with PDAC (76/100) using CTCs enriched via a microfluidic assay. A cut-off value of two vimentin+ CTCs distinguished patients with PDAC from healthy individuals. Combined vimentin+ CTCs and Carbohydrate antigen 19-9 provided favorable diagnostic potency, with an area under the curve of 0.968. Vimentin+ CTCs counts correlated with the change in tumor burden for patients undergoing resection. Significantly reduced CTC counts were observed after chemotherapy in subjects that responded to treatment. Preoperatively higher CTCs counts correlated with shortened recurrence-free survival. Taken together, vimentin+ CTCs could be a reliable biomarker in pancreatic cancer. The enrichment of mesenchymal CTCs complements the strategy of capturing epithelial CTCs, allowing a more thorough interrogation of the biology and clinical significance of CTCs in PDAC. [ABSTRACT FROM AUTHOR]

Exosomal-miRNAs are emerging as mediators of crosstalk between tumor cells and macrophages. In this study, we observed that exosomes derived from TWEAK-stimulated macrophages (TMs) could be internalized by epithelial ovarian cancer (EOC) cells and inhibit cell metastasis. Through a miRNA microarray analysis, we identified 19 miRNAs that are differentially expressed in exosomes derived from macrophages treated with or without TWEAK. The study validated that TWEAK not only increased the levels of microRNA-7 (miR-7) in macrophages and its secreted exosomes but also resulted in an elevated level of miR-7 in recipient EOC cells, which eventually reduced the activity of the EGFR/AKT/ERK1/2 pathway. Pre-transfection of antagomiR-7 in TMs substantially decreased the levels of miR-7 in macrophages, its secreted exosomes and the recipient EOC cells with a concomitant enhancement of EOC metastasis, suggesting an involvement of exosomal miR-7 from TMs in modulating the metastasis of EOC cells. Finally, the exosomes from TMs significantly blocked EOC metastasis in a xenograft mouse model. These findings provide a novel model in which TMs inhibit the metastasis of EOC cells via shuttling of exosomal miR-7 to EOC cells, thereby inhibiting the EGFR/AKT/ERK1/2 pathway. [ABSTRACT FROM AUTHOR]

Using a high-throughput approach, we identified lemur tyrosine kinase 2 (LMTK2) as a novel determinant of cell sensitivity to TRAIL. LMTK2 is a poorly characterized serine/threonine kinase believed to play a role in endosomal membrane trafficking and neuronal physiology, and recently found to be mutated in diverse tumor types. We show that LMTK2 silencing sensitizes immortalized epithelial cells and cancer cells to TRAIL, and this phenomenon is accompanied by changes in the expression of BCL2 family members. In epithelial cells, LMTK2 targeting causes the down-regulation of the BCL2 and BCL-xL anti-apoptotic proteins and the reciprocal up-regulation of the pro-apoptotic protein BIM, while, in cancer cells, LMTK2 knock-down reduces BCL2 without increasing BIM levels. We provide evidence that both BIM and BCL2 proteins are regulated by LMTK2 in a GSK3β- and PP1A-dependent manner and that their perturbation, together with BCL-xL reduction, determines an increased sensitivity not only to TRAIL, but also to other compounds. Overall, our findings suggest a broad function of LMTK2 in the regulation of the apoptotic pathway and highlight LMTK2 as a novel candidate target to increase the cytotoxic activity of chemotherapeutic compounds. [ABSTRACT FROM AUTHOR]

Although cancer-associated fibroblasts (CAFs) are viewed as a promising therapeutic target, the design of rational therapy has been hampered by two key obstacles. First, attempts to ablate CAFs have resulted in significant toxicity because currently used biomarkers cannot effectively distinguish activated CAFs from non-cancer associated fibroblasts and mesenchymal progenitor cells. Second, it is unclear whether CAFs in different organs have different molecular and functional properties that necessitate organ-specific therapeutic designs. Our analyses uncovered COL11A1 as a highly specific biomarker of activated CAFs. Using COL11A1 as a 'seed', we identified co-expressed genes in 13 types of primary carcinoma in The Cancer Genome Atlas. We demonstrated that a molecular signature of activated CAFs is conserved in epithelial cancers regardless of organ site and transforming events within cancer cells, suggesting that targeting fibroblast activation should be effective in multiple cancers. We prioritized several potential pan-cancer therapeutic targets that are likely to have high specificity for activated CAFs and minimal toxicity in normal tissues. [ABSTRACT FROM AUTHOR]

The miR-17~92 microRNA (miRNA) cluster host gene is upregulated in a broad spectrum of human cancers including colorectal cancer (CRC). Previous studies have shown that miR-17~92 promotes tumorigenesis and cancer angiogenesis in some tumor models. However, its role in the initiation and progression of CRC remains unknown. In this study, we found that transgenic mice overexpressing miR-17~92 specifically in epithelial cells of the small and large intestines exhibited decreased tumor size and tumor angiogenesis in azoxymethane and dextran sulfate sodium salt (AOM-DSS)-induced CRC model as compared to their littermates control. Further study showed that miR-17~92 inhibited the progression of CRC via suppressing tumor angiogenesis through targeting multiple tumor angiogenesis-inducing genes, TGFBR2, HIF1α, and VEGFA in vivo and in vitro. Collectively, we demonstrated that miR-17~92 suppressed tumor progression by inhibiting tumor angiogenesis in a genetically engineered mouse model, indicating the presence of cellular context-dependent pro- and anti-cancer effects of miR-17~92. [ABSTRACT FROM AUTHOR]

ATAD5/ELG1 is a protein crucially involved in replication and maintenance of genome stability. ATAD5 has recently been identified as a genomic risk locus for both breast and ovarian cancer through genome-wide association studies. We aimed to investigate the spectrum of coding ATAD5 germ-line mutations in hospital-based series of patients with triple-negative breast cancer or serous ovarian cancer compared with healthy controls. The ATAD5 coding and adjacent splice site regions were analyzed by targeted next-generation sequencing of DNA samples from 273 cancer patients, including 114 patients with triple-negative breast cancer and 159 patients with serous epithelial ovarian cancer, and from 276 healthy females. Among 42 different variants identified, twenty-two were rare missense substitutions, of which 14 were classified as pathogenic by at least one in silico prediction tool. Three of four novel missense substitutions (p.S354I, p.H974R and p.K1466N) were predicted to be pathogenic and were all identified in ovarian cancer patients. Overall, rare missense variants with predicted pathogenicity tended to be enriched in ovarian cancer patients (14/159) versus controls (11/276) (p = 0.05, 2df). While truncating germ-line variants in ATAD5 were not detected, it remains possible that several rare missense variants contribute to genetic susceptibility toward epithelial ovarian carcinomas. [ABSTRACT FROM AUTHOR]

This study aimed to describe cancer incidence rates and trends specifically for adolescents aged 15-19 years during 1995-2009 in Taiwan. The incidence counts and census data were obtained from the population-based Taiwan Cancer Registry. During the 15-year study period, 4122 adolescents were diagnosed with cancer. The overall incidence rate was 155.2 per million person-years. Other epithelial tumors were the most frequently diagnosed cancer group (23.7%), followed by leukemias (18.0%) and lymphomas (13.9%). When compared to rates in Western countries, a significantly low rate of lymphomas was found. Moreover, rates of the subtypes of melanomas and nasopharyngeal carcinomas being 1/10- and 4-times rates in Western countries were the most striking variations. During 1995-2009, the overall rate of adolescent cancer did not significantly change. However, the most significant upward and declining trends in incidence rates were found for male germ cell neoplasms (annual percent change, APC, 6.4%) and hepatic tumors (APC, -11.1%), respectively. Further investigation and enhancement of the public discourse of possible lifestyle and environmental risk factors associated with increasing trends of certain adolescent cancers should be carried out in Taiwan. [ABSTRACT FROM AUTHOR]

In the last few years, the role of epithelial cell plasticity in cancer biology research has gained increasing attention. This concept refers to the ability of the epithelial cells to dynamically switch between different phenotypic cellular states. This programme is particularly relevant during the epithelial-to-mesenchymal transition (EMT) in cancer progression. During colonization, epithelial cells first activate the EMT programme to disseminate from a primary tumour to reach a distant tissue site. During this process, cells are transported into the circulation and are able to escape the immune system of the host. Then, a reverse process called mesenchymal-to-epithelial transition (MET) occurs on cells that settle in the distant organs. Although epithelial cell plasticity has an important impact on tumour biology, the clinical relevance of this concept remains to be recapitulated. In this review, we will update the current state of epithelial cell plasticity in cancer progression and its clinical implications for the design of therapeutic strategies, the acquisition of multidrug resistance, and future perspectives for the management of cancer patients. [ABSTRACT FROM AUTHOR]

Epigenetic modification of miR-429 can manipulate liver T-ICs via targeting the RBBP4/E2F1/Oct4 axis, which might be crucial for hepatocarcinogenesis. However, whether miR-429 plays a role in regulating metastasis of hepatocellular carcinoma is still unclear. Using quantitative methylation analysis and real-time PCR, we have identified the hypomethylated status and upregulation of miR-429 in portal vein metastasis samples in comparison with their matched primary tumor. The ectopic expression of miR-429 dramatically induced the expression of MMP2/7/9 and enhanced HCC migration and invasion in vitro and in vivo in an EMT-independent manner. Both bioinformatics and functional studies elucidated the direct regulation of miR-429 on the 3′UTR of the PTEN gene, which leads to the activation of PI3K/AKT signaling and the nuclear translocation of β-catenin, eventually. Conversely, the knockdown of miR-429 efficiently recovered the expression of PTEN and attenuated PI3K/AKT/β-catenin-mediated cell metastasis. Clinically, the higher expression of miR-429 and nucleus relocation of β-catenin were identified as the adverse prognosis factors for recurrence-free survival (RFS) and overall survival (OS). In summary, our results here defined miR-429 as a key inducer for HCC pathogenesis and metastasis with potential utility for tumor intervention. [ABSTRACT FROM AUTHOR]

Epithelial–mesenchymal transition (EMT) induces invasive properties in epithelial tumors and promotes metastasis. Although EMT-mediated cellular and molecular changes are well understood, very little is known about EMT-induced metabolic changes. HER2-positive BT-474 breast cancer cells were induced to undergo a stable EMT using mammosphere culture, as previously described by us for the ERα-positive MCF-7 breast cancer cells. Two epithelial breast cancer cell lines (BT-474 and MCF-7) were compared to their respective EMT-derived mesenchymal progeny (BT-474 EMT and MCF-7 EMT ) for changes in metabolic pathways including glycolysis, glycogen metabolism, anabolic pathways and gluconeogenesis. Both EMT-derived cells displayed enhanced aerobic glycolysis along with the overexpression of specific glucose transporters, lactate dehydrogenase isoforms, monocarboxylate transporters and glycogen phosphorylase isoform. In contrast, both EMT-derived cells suppressed the expression of crucial enzymes in anabolic pathways and gluconeogenesis. STAT3, a transcription factor involved in tumor initiation and progression, plays a role in the EMT-related changes in the expression of specific enzymes and transporters. This study provides a broad overview of similar metabolic changes induced by EMT in two independent breast cancer cell lines. These metabolic changes may provide novel therapeutic targets for metastatic breast cancer. [ABSTRACT FROM AUTHOR]

Highlights: [•] Based on genetically engineered mouse, we analyzed the biological features of PanIN. [•] PanIN showed tumorigenic ability, but did not undergo a malignant transformation. [•] We first found the differential expression of PPP2R2A between PanIN and PDAC. [•] PPP2R2A expression is significantly higher in PanIN tissues than PDAC tissues. [•] The expression of PPP2R2A appears to be correlated with clinical survival. [Copyright &y& Elsevier]

Serous, mucinous, endometrioid, and clear cell adenocarcinomas arise from reproductive organs of mullerian origin. Although the mutation of PTEN, a tumor suppressor, is known to be involved in tumorigenesis of endometrioid adenocarcinomas of the endometrium and ovary, the role of PTEN alteration in endometrioid adenocarcinoma of the cervix remains to be investigated. To elucidate the molecular pathogenesis of cervical adenocarcinoma and adenosquamous carcinoma, and in particular to examine the potential role of PTEN mutation in endometrioid-type cancer of the cervix, we analyzed 32 cervical adeno- or adenosquamous carcinomas (8 endometrioid adenocarcinomas, 14 mucinous adenocarcinomas and 10 adenosquamous carcinomas) for PTEN mutations and HPV infections. PTEN mutation was detected in 2 of 8 (25.0%) endometrioid cases, 2 of 14 (14.3%) mucinous cases, and none of 10 (0%) adenosquamous cases. HPV DNA was detected in 11 out of 18 (61.1%) PTEN wild-type adenocarcinomas and 8 out of 10 (80.0%) adenosquamous carcinomas. Among 11 HPV-negative adenocarcinomas, 40.0% (2/5) endometrioid cases and 33.3% (2/6) mucinous cases were shown to be PTEN mutated, while no cases (0/21) were PTEN-mutant in the remainder (i.e. adenosquamous carcinomas and HPV-positive adenocarcinomas). The current observations suggest that PTEN mutation is frequently detected in HPV-negative adenocarcinomas of the cervix and the most prevalent occurrence of PTEN mutation in endometrioid subtype is keeping with endometrial and ovarian carcinomas. [ABSTRACT FROM AUTHOR]

Recently, the p53R2 gene has been isolated and shown to play a crucial role in DNA repair after DNA damage. The p53R2 gene encodes the p53 inducible ribonucleotide reductase small subunit 2 homologue, which is part of the p53 pathway. However, the function of p53R2 in human cancer is still unclear. We investigated p53R2 mRNA expression in human oral normal epithelium, epithelial dysplasias and squamous cell carcinomas (SCCs). Surgical or biopsy-proven specimens of 10 normal epithelium, 48 epithelial dysplasias and 63 SCCs were collected in our department. Then, p53R2 was identified by in situ hybridization to visualize and localize the expression of specific mRNAs. The authors examined the p53 gene mutation by polymerase chain reaction-single strand conformation polymorphism analysis. p53, mdm2, p21WAF1/CIP1 and Ki-67 expression was detected by immunohistochemistry. p53R2 expression was detected in none of ten normal epithelium (0%), ten of 48 dysplasias (20.8%) and 33 of 63 SCCs (52.4%). In oral SCC, the expression of p53R2 was significantly associated with tumor size, lymph node metastasis and histological differentiation (P=0.014, 0.046 and 0.022, respectively). p53R2 expression was significantly associated with p53 abnormality in epithelial dysplasia and SCC (P=0.034 and 0.009, respectively). Of 63 patients, 37 received preoperative radiochemotherapy. p53R2 mRNA expression was significantly associated with the pathologic response to radiochemotherapy (P=0.031). This study suggested that p53R2 expression could be associated with oral carcinogenesis. The presence of p53R2 mRNA expression would be a predictive factor for tumor development, tumor cell differentiation and the sensitivity to radiochemotherapy in oral SCC. [Copyright &y& Elsevier]

In oral and maxillofacial surgery, epinephrine is routinely used for cancer resection and it is important to clarify the effects of this agent on cancer. We found here that the clinically relevant concentrations of epinephrine (10, 50 and 100 μg/ml) decreased the invasion ability of oral squamous carcinoma (Sa3) cells. In the Sa3 cells treated with epinephrine (10, 50 and 100 μg/ml), migration, morphological changes and formation of actin stress fibers were inhibited and intracellular cyclic adenosine monophosphate (cAMP) increased significantly. These findings suggest that epinephrine inhibits the invasion of cancer cells by modulating intracellular cAMP and that clinicians could use epinephrine effectively for the surgical resection of the cancer. [Copyright &y& Elsevier]

Ovarian cancer is the fifth leading cause of cancer deaths in U.S. women and the deadliest gynecologic malignancy. This lethality is largely due to the fact that most cases are diagnosed at metastatic stages of the disease when the prognosis is poor. Epidemiologic studies consistently demonstrate that parous women have a reduced risk of developing ovarian cancer, with a greater number of births affording greater protection; however little is known about the impact of parity on ovarian cancer metastasis. Here we report that multiparous mice are less susceptible to ovarian cancer metastasis in an age-matched syngeneic murine allograft model. Interferon pathways were found to be upregulated in healthy adipose tissue of multiparous mice, suggesting a possible mechanism for the multiparous-related protective effect against metastasis. This protective effect was found to be lost with age. Based on this work, future studies exploring therapeutic strategies which harness the multiparity-associated protective effect demonstrated here are warranted. [ABSTRACT FROM AUTHOR]