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Brandi B Knight, Gabriela M Oprea-Ilies, Arumugam Nagalingam, Lily Yang, Cynthia Cohen, Neeraj K Saxena, and Dipali Sharma

Obese breast cancer patients exhibit a higher risk for larger tumor burden and an increased likelyhood of metastasis. The molecular effects of obesity on carcinogenesis are mediated by the autocrine and paracrine effects of the adipocytokine leptin. Leptin participates in the tumor progression and metastasis of human breast. We show that leptin induces clonogenicity and increases the migration potential of breast cancer cells. We found that survivin expression is induced in response to leptin. In this study, we examine the role and leptin-mediated regulation of survivin. Leptin treatment leads to survivin upregulation, due in part to the activation of Notch1 and the release of a transcriptionally active Notch1 intracellular domain (NICD). Chromatin immunoprecipitation analysis shows that NICD gets recruited to the survivin promoter at the CSL (CBF1/RBP-Jk, Su(H), Lag-1) binding site in response to leptin treatment. Inhibition of Notch1 activity inhibits leptin-induced survivin upregulation. Leptin-induced transactivation of epidermal growth factor receptor (EGFR) is involved in leptin-mediated Notch1 and survivin upregulation, demonstrating a novel upstream role of leptin–EGFR–Notch1 axis. We further show that leptin-induced migration of breast cancer cells requires survivin, as overexpression of survivin further increases, whereas silencing survivin abrogates leptin-induced migration. Using a pharmacological approach to inhibit survivin, we show that 3-hydroxy-3-methylglutaryl-coenzyme-A-reductase inhibitors, such as lovastatin, can effectively inhibit leptin-induced survivin expression and migration. Importantly, leptin increased breast tumor growth in nude mice. These data show a novel role for survivin in leptin-induced migration and put forth pharmacological survivin inhibition as a potential novel therapeutic strategy. This conclusion is supported by in vivo data showing the overexpression of leptin and survivin in epithelial cells of high-grade ductal carcinomas in situ and in high-grade invasive carcinomas.

Free access

Y Capodanno, F O Buishand, L Y Pang, J Kirpensteijn, J A Mol, and D J Argyle

Insulinomas (INS) are the most common neuroendocrine pancreatic tumours in humans and dogs. The long-term prognosis for malignant INS is still poor due to a low success rate of the current treatment modalities, particularly chemotherapy. A better understanding of the molecular processes underlying the development and progression of INS is required to develop novel targeted therapies. Cancer stem cells (CSCs) are thought to be critical for the engraftment and chemoresistance of many tumours, including INS. This study was aimed to characterise and target INS CSCs in order to develop novel targeted therapies. Highly invasive and tumourigenic human and canine INS CSC-like cells were successfully isolated. These cells expressed stem cell markers (OCT4, SOX9, SOX2, CD133 and CD34), exhibited greater resistance to 5-fluorouracil (5-FU) and demonstrated a more invasive and tumourigenic phenotype in vivo compared to bulk INS cells. Here, we demonstrated that Notch-signalling-related genes (NOTCH2 and HES1) were overexpressed in INS CSC-like cells. Protein analysis showed an active NOTCH2-HES1 signalling in INS cell lines, especially in cells resistant to 5-FU. Inhibition of the Notch pathway, using a gamma secretase inhibitor (GSI), enhanced the sensitivity of INS CSC-like cells to 5-FU. When used in combination GSI and 5-FU, the clonogenicity in vitro and the tumourigenicity in vivo of INS CSC-like cells were significantly reduced. These findings suggested that the combined strategy of Notch signalling inhibition and 5-FU synergistically attenuated enriched INS CSC populations, providing a rationale for future therapeutic exploitation.

Free access

Cuong V Duong, Richard D Emes, Frank Wessely, Kiren Yacqub-Usman, Richard N Clayton, and William E Farrell

DNA methylation is one of the several epigenetic modifications that together with genetic aberrations are hallmarks of tumorigenesis including those emanating from the pituitary gland. In this study, we examined DNA methylation across 27 578 CpG sites spanning more than 14 000 genes in the major pituitary adenoma subtypes. Genome-wide changes were first determined in a discovery cohort comprising non-functioning (NF), growth hormone (GH), prolactin (PRL)-secreting and corticotroph (CT) adenoma relative to post-mortem pituitaries. Using stringent cut-off criteria, we validated increased methylation by pyrosequencing in 12 of 16 (75%) genes. Overall, these criteria identified 40 genes in NF, 21 in GH, six in PRL and two in CT that were differentially methylated relative to controls. In a larger independent cohort of adenomas, for genes in which hypermethylation had been validated, different frequencies of hypermethylation were apparent, where the KIAA1822 (HHIPL1) and TFAP2E genes were hypermethylated in 12 of 13 NF adenomas whereas the COL1A2 gene showed an increase in two of 13 adenomas. For genes showing differential methylation across and between adenoma subtypes, pyrosequencing confirmed these findings. In three of 12 genes investigated, an inverse relationship between methylation and transcript expression was observed where increased methylation of EML2, RHOD and HOXB1 is associated with significantly reduced transcript expression. This study provides the first genome-wide survey of adenoma, subtype-specific epigenomic changes and will prove useful for identification of biomarkers that perhaps predict or characterise growth patterns. The functional characterisation of identified genes will also provide insight of tumour aetiology and identification of new therapeutic targets.

Restricted access

I Számel, B Budai, K Daubner, J Kralovánszky, Sz Ottó, J Tóth, and I Besznyák

ABSTRACT

Gross cystic disease (GCD) of the breast may be associated with a higher risk for the development of breast cancer. High levels of sex steroids, steroid hormone precursors, prolactin and cations have been found in breast cyst fluid (BCF) by several investigators. Accordingly, endocrine parameters and the cationic composition of BCF may be considered as useful characteristics to follow patients bearing macrocysts. In this study we have investigated the concentrations of estradiol (E2), progesterone, testosterone, dehydroepiandrosterone (DHA) and DHA-3-sulfate (DHA-S), prolactin, potassium (K+) and sodium (Na+) in BCF aspirated from 99 women. The mean age of the patients was 49.8 years (range 32-58). The hormone levels were measured by RIA methods; K+ and Na+ were determined by flame photometry. Estradiol, progesterone, testosterone, DHA, DHA-S, prolactin and K+ showed significant accumulation in the BCF compared with their respective serum values. The K+/Na+ ratio proved to be useful in dividing cysts into type I (≥1), type II (<1 but ≥0.1) and type III (<0.1) subgroups. For type I BCF, higher DHA, DHA-S and prolactin concentrations were detected. Linear regression analysis established a highly significant (P<0.001) correlation between the concentrations of E2 and DHA-S (r=0.686), and also between testosterone and DHA-S (r=0.711). These findings indicate that type I BCF might be a marker for 'active' GCD of the breast, and suggest that it may be associated with an increased breast cancer risk, since this group of patients is supposed to have cysts with apocrine metaplasia. It is suggested therefore that when BCF is aspirated, sex steroids, steroid precursors and cations should be routinely measured, and women with type I cysts should be regularly examined.

Free access

Antonella Verrienti, Giovanni Tallini, Chiara Colato, Amélie Boichard, Saula Checquolo, Valeria Pecce, Marialuisa Sponziello, Francesca Rosignolo, Dario de Biase, Kerry Rhoden, Gian Piero Casadei, Diego Russo, Michela Visani, Giorgia Acquaviva, Marco Ferdeghini, Sebastiano Filetti, and Cosimo Durante

Advanced medullary thyroid cancers (MTCs) are now being treated with drugs that inhibit receptor tyrosine kinases, many of which involved in angiogenesis. Response rates vary widely, and toxic effects are common, so treatment should be reserved for MTCs likely to be responsive to these drugs. RET mutations are common in MTCs, but it is unclear how they influence the microvascularization of these tumors. We examined 45 MTCs with germ-line or somatic RET mutations (RETmut group) and 34 with wild-type RET (RETwt). Taqman Low-Density Arrays were used to assess proangiogenic gene expression. Immunohistochemistry was used to assess intratumoral, peritumoral and nontumoral expression levels of VEGFR1, R2, R3, PDGFRa, PDGFB and NOTCH3. We also assessed microvessel density (MVD) and lymphatic vessel density (LVD) based on CD31-positive and podoplanin-positive vessel counts, respectively, and vascular pericyte density based on staining for a-smooth muscle actin (a-SMA), a pericyte marker. Compared with RETwt tumors, RETmut tumors exhibited upregulated expression of proangiogenic genes (mRNA and protein), especially VEGFR1, PDGFB and NOTCH3. MVDs and LVDs were similar in the two groups. However, microvessels in RETmut tumors were more likely to be a-SMA positive, indicating enhanced coverage by pericytes, which play key roles in vessel sprouting, maturation and stabilization. These data suggest that angiogenesis in RETmut MTCs may be more intense and complete than that found in RETwt tumors, a feature that might increase their susceptibility to antiangiogenic therapy. Given their increased vascular pericyte density, RETmut MTCs might also benefit from combined or preliminary treatment with PDGF inhibitors.

Free access

Luca Morandi, Alberto Righi, Francesca Maletta, Paola Rucci, Fabio Pagni, Marco Gallo, Sabrina Rossi, Leonardo Caporali, Anna Sapino, Ricardo V Lloyd, and Sofia Asioli

Hobnail variant of papillary thyroid carcinoma (HPTC) represents a recently described, aggressive and rare group of thyroid tumors with poorly understood pathogenesis. Molecular data about this group of cancers are few, and a more detailed molecular characterization of these tumors is needed. The main objective of the study is to define a comprehensive molecular typing of HPTC. Eighteen patients affected by HPTC, including eighteen primary tumors and four lymph node metastases, were screened for NRAS, KRAS, HRAS, BRAF, TP53, PIK3CA, hTERT, PTEN, CDKN2A, EGFR, AKT1, CTNNB1 and NOTCH1 gene mutations. Sequencing is conducted on the MiSEQ system, and molecular data are compared with clinical-pathologic data and follow-up. The patients include 14 women and 4 men. Ages range from 23 to 87 years. All 18 primary tumors of HPTC showed ≥30% hobnail features. BRAF and TP53 mutations are by far the most common genetic alterations in primary HPTC (72.2% and 55.6%, respectively), followed by hTERT (44.4%), PIK3CA (27.8%), CTNNB1 (16.7%), EGFR (11.1%), AKT1 (5.5%) and NOTCH1 (5.5%). The mutational pattern in primary tumors and metastasis was usually maintained. Univariate Cox regression analyses with bootstrap procedure indicated a significantly increased mortality risk in patients harboring BRAF mutation and BRAF mutation associated with TP53 and/or PIK3CA mutations. The detection of these multiple mutations appears to allow the identification of a subset of more aggressive tumors within the group and to bear information that should be useful for prognostic stratification of these patients including the planning of adjuvant therapy.

Free access

S K Kang, K-C Choi, H-S Yang, and P C K Leung

Gonadotrophin-releasing hormone (GnRH) functions as a key neuroendocrine regulator of the hypothalamic-pituitary-gonadal axis. In addition to the hypothalamus and pituitary gland, GnRH and its receptor have been detected in other reproductive tissues including the gonads, placenta and tumours arising from these tissues. Recently, a second form of GnRH (GnRH-II) and type II GnRH receptor have been found in normal ovarian surface epithelium and neoplastic counterparts. The two types of GnRH may play an important role as an autocrine/paracrine regulator of reproductive functions and ovarian tumour growth. In this review, the distribution and potential roles of GnRH-I/-II and their GnRH receptors in the ovarian cells and ovarian cancer will be discussed.

Free access

Rafael Ríos, Carmen Belén Lupiañez, Daniele Campa, Alessandro Martino, Joaquin Martínez-López, Manuel Martínez-Bueno, Judit Varkonyi, Ramón García-Sanz, Krzysztof Jamroziak, Charles Dumontet, Andrés Jerez Cayuela, Marzena Wętek, Stephano Landi, Anna Maria Rossi, Fabienne Lesueur, Rui Manuel Reis, Victor Moreno, Herlander Marques, Artur Jurczyszyn, Vibeke Andersen, Ulla Vogel, Gabriele Buda, Enrico Orciuolo, Svend E H Jacobsen, Mario Petrini, Annette J Vangsted, Federica Gemignani, Federico Canzian, Manuel Jurado, and Juan Sainz

Type 2 diabetes (T2D) has been suggested to be a risk factor for multiple myeloma (MM), but the relationship between the two traits is still not well understood. The aims of this study were to evaluate whether 58 genome-wide-association-studies (GWAS)-identified common variants for T2D influence the risk of developing MM and to determine whether predictive models built with these variants might help to predict the disease risk. We conducted a case–control study including 1420 MM patients and 1858 controls ascertained through the International Multiple Myeloma (IMMEnSE) consortium. Subjects carrying the KCNQ1 rs2237892T allele or the CDKN2A-2B rs2383208G/G, IGF1 rs35767T/T and MADD rs7944584T/T genotypes had a significantly increased risk of MM (odds ratio (OR)=1.32–2.13) whereas those carrying the KCNJ11 rs5215C, KCNJ11 rs5219T and THADA rs7578597C alleles or the FTO rs8050136A/A and LTA rs1041981C/C genotypes showed a significantly decreased risk of developing the disease (OR=0.76–0.85). Interestingly, a prediction model including those T2D-related variants associated with the risk of MM showed a significantly improved discriminatory ability to predict the disease when compared to a model without genetic information (area under the curve (AUC)=0.645 vs AUC=0.629; P=4.05×10 06). A gender-stratified analysis also revealed a significant gender effect modification for ADAM30 rs2641348 and NOTCH2 rs10923931 variants (P interaction=0.001 and 0.0004, respectively). Men carrying the ADAM30 rs2641348C and NOTCH2 rs10923931T alleles had a significantly decreased risk of MM whereas an opposite but not significant effect was observed in women (ORM=0.71 and ORM=0.66 vs ORW=1.22 and ORW=1.15, respectively). These results suggest that TD2-related variants may influence the risk of developing MM and their genotyping might help to improve MM risk prediction models.

Free access

Yu-fang Bi, Rui-xin Liu, Lei Ye, Hai Fang, Xiao-ying Li, Wei-qing Wang, Ji Zhang, Kan-Kan Wang, Lei Jiang, Ting-wei Su, Zhong-yuan Chen, and Guang Ning

Although there has been increased knowledge about the molecular biology of neuroendocrine tumors (NETs), little is known about thymic carcinoids and even less about those with excessive hormone disorders, such as ectopic ACTH syndrome. This study was designed to gain insights into the molecular networks underlying the tumorigenesis of thymic carcinoids with ACTH secretion. By an approach integrating cDNA microarray and methods of computational biology, we compare gene expression profile between ACTH-producing thymic carcinoids and the normal thymus. In total, there are 63 biological categories increased and 108 decreased in thymic carcinoids. Cell proliferation was stimulated, which may explain the relatively uncontrolled cell growth of the tumor. Dysregulation of the Notch-signaling pathway was likely to be underlying the neuroendocrine features of this type of tumors. Moreover, inhibition of immunity and increased neuropeptide signaling molecules (POMC and its sorting molecule CPE) made the clinical manifestation reasonable and thus validated the array data. In conclusion, thymic carcinoids have a distinct gene expression pattern from the normal thymus, and they are characterized by deregulations of a series of biofunctions, which may be involved in the development of NETs. Hence, this study has provided not only a detailed comprehension of the molecular pathogenesis of thymic carcinoids with ectopic ACTH syndrome, but also a road map to approach thymic NETs at the system level.

Free access

Fazlul H Sarkar, Yiwei Li, Zhiwei Wang, and Dejuan Kong

Among many endocrine-related cancers, prostate cancer (PCa) is the most frequent male malignancy, and it is the second most common cause of cancer-related death in men in the United States. Therefore, this review focuses on summarizing the knowledge of molecular signaling pathways in PCa because, in order to better design new preventive strategies for the fight against PCa, documentation of the knowledge on the pathogenesis of PCa at the molecular level is very important. Cancer cells are known to have alterations in multiple cellular signaling pathways; indeed, the development and the progression of PCa are known to be caused by the deregulation of several selective signaling pathways such as the androgen receptor, Akt, nuclear factor-κB, Wnt, Hedgehog, and Notch. Therefore, strategies targeting these important pathways and their upstream and downstream signaling could be promising for the prevention of PCa progression. In this review, we summarize the current knowledge regarding the alterations in cell signaling pathways during the development and progression of PCa, and document compelling evidence showing that these are the targets of several natural agents against PCa progression and its metastases.