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Open access

Takeshi Ujike, Motohide Uemura, Atsunari Kawashima, Akira Nagahara, Kazutoshi Fujita, Yasushi Miyagawa, and Norio Nonomura

Circulating levels of prostate-specific antigen (PSA) and testosterone are widely used for the detection of prostate cancer prior to prostate biopsy; however, both remain controversial. Effective screening strategies based on quantitative factors could help avoid unnecessary biopsies. Here, we sought to clarify the predictive value of free testosterone (FT) vs total testosterone (TT) in identifying patients likely to have positive biopsies. This study aims to develop a novel model for predicting positive prostate biopsy based on serum androgen levels. This study included 253 Japanese patients who underwent prostate biopsy at our institution. TT and FT, %FT (=FT/TT), age, PSA, prostate volume (PV) and PSA density (PSAD = PSA/PV) were assessed for association with prostate biopsy findings. The following results were obtained. Of 253 patients, 145 (57.3%) had positive biopsies. Compared to the negative biopsy group, the positive biopsy group demonstrated higher age, PSA and PSAD but lower PV, FT and %FT by univariate analysis. Multivariate logistic regression analysis indicated PSA, PSAD and %FT were independent predictors of cancer detection. We developed a predictive model based on PSAD and %FT, for which the area under the curve was significantly greater than that of PSA (0.82 vs 0.66), a well-known predictor. Applying this analysis to the subset of patients with PSA <10 ng/mL yielded similar results. We confirmed the utility of this model in another independent cohort of 88 patients. In conclusion, lower %FT predicted a positive prostate biopsy. We constructed a predictive model based on %FT and PSAD, which are easily obtained prior to biopsy.

Open access

Hongqiang Wang, Rui Zhou, Li Sun, Jianling Xia, Xuchun Yang, Changqie Pan, Na Huang, Min Shi, Jianping Bin, Yulin Liao, and Wangjun Liao

Aerobic glycolysis plays an important role in cancer progression. New target genes regulating cancer aerobic glycolysis must be explored to improve patient prognosis. Mitochondrial topoisomerase I (TOP1MT) deficiency suppresses glucose oxidative metabolism but enhances glycolysis in normal cells. Here, we examined the role of TOP1MT in gastric cancer (GC) and attempted to determine the underlying mechanism. Using in vitro and in vivo experiments and analyzing the clinicopathological characteristics of patients with GC, we found that TOP1MT expression was lower in GC samples than in adjacent nonmalignant tissues. TOP1MT knockdown significantly promoted GC migration and invasion in vitro and in vivo. Importantly, TOP1MT silencing increased glucose consumption, lactate production, glucose transporter 1 expression and the epithelial-mesenchymal transition (EMT) in GC. Additionally, regulation of glucose metabolism induced by TOP1MT was significantly associated with lactate dehydrogenase A (LDHA) expression. A retrospective analysis of clinical data from 295 patients with GC demonstrated that low TOP1MT expression was associated with lymph node metastasis, recurrence and high mortality rates. TOP1MT deficiency enhanced glucose aerobic glycolysis by stimulating LDHA to promote GC progression.

Open access

Patrick Petrossians, Adrian F Daly, Emil Natchev, Luigi Maione, Karin Blijdorp, Mona Sahnoun-Fathallah, Renata Auriemma, Alpha M Diallo, Anna-Lena Hulting, Diego Ferone, Vaclav Hana Jr, Silvia Filipponi, Caroline Sievers, Claudia Nogueira, Carmen Fajardo-Montañana, Davide Carvalho, Vaclav Hana, Günter K Stalla, Marie-Lise Jaffrain-Réa, Brigitte Delemer, Annamaria Colao, Thierry Brue, Sebastian J C M M Neggers, Sabina Zacharieva, Philippe Chanson, and Albert Beckers

Acromegaly is a rare disorder caused by chronic growth hormone (GH) hypersecretion. While diagnostic and therapeutic methods have advanced, little information exists on trends in acromegaly characteristics over time. The Liège Acromegaly Survey (LAS) Database, a relational database, is designed to assess the profile of acromegaly patients at diagnosis and during long-term follow-up at multiple treatment centers. The following results were obtained at diagnosis. The study population consisted of 3173 acromegaly patients from ten countries; 54.5% were female. Males were significantly younger at diagnosis than females (43.5 vs 46.4 years; P < 0.001). The median delay from first symptoms to diagnosis was 2 years longer in females (P = 0.015). Ages at diagnosis and first symptoms increased significantly over time (P < 0.001). Tumors were larger in males than females (P < 0.001); tumor size and invasion were inversely related to patient age (P < 0.001). Random GH at diagnosis correlated with nadir GH levels during OGTT (P < 0.001). GH was inversely related to age in both sexes (P < 0.001). Diabetes mellitus was present in 27.5%, hypertension in 28.8%, sleep apnea syndrome in 25.5% and cardiac hypertrophy in 15.5%. Serious cardiovascular outcomes like stroke, heart failure and myocardial infarction were present in <5% at diagnosis. Erythrocyte levels were increased and correlated with IGF-1 values. Thyroid nodules were frequent (34.0%); 820 patients had colonoscopy at diagnosis and 13% had polyps. Osteoporosis was present at diagnosis in 12.3% and 0.6–4.4% had experienced a fracture. In conclusion, this study of >3100 patients is the largest international acromegaly database and shows clinically relevant trends in the characteristics of acromegaly at diagnosis.

Open access

Catherine Zabkiewicz, Jeyna Resaul, Rachel Hargest, Wen Guo Jiang, and Lin Ye

Bone morphogenetic proteins (BMPs) belong to the TGF-β super family, and are essential for the regulation of foetal development, tissue differentiation and homeostasis and a multitude of cellular functions. Naturally, this has led to the exploration of aberrance in this highly regulated system as a key factor in tumourigenesis. Originally identified for their role in osteogenesis and bone turnover, attention has been turned to the potential role of BMPs in tumour metastases to, and progression within, the bone niche. This is particularly pertinent to breast cancer, which commonly metastasises to bone, and in which studies have revealed aberrations of both BMP expression and signalling, which correlate clinically with breast cancer progression. Ultimately a BMP profile could provide new prognostic disease markers. As the evidence suggests a role for BMPs in regulating breast tumour cellular function, in particular interactions with tumour stroma and the bone metastatic microenvironment, there may be novel therapeutic potential in targeting BMP signalling in breast cancer. This review provides an update on the current knowledge of BMP abnormalities and their implication in the development and progression of breast cancer, particularly in the disease-specific bone metastasis.

Open access

W Imruetaicharoenchoke, A Fletcher, W Lu, R J Watkins, B Modasia, V L Poole, H R Nieto, R J Thompson, K Boelaert, M L Read, V E Smith, and C J McCabe

Pituitary tumor-transforming gene 1-binding factor (PTTG1IP; PBF) is a multifunctional glycoprotein, which is overexpressed in a wide range of tumours, and significantly associated with poorer oncological outcomes, such as early tumour recurrence, distant metastasis, extramural vascular invasion and decreased disease-specific survival. PBF transforms NIH 3T3 fibroblasts and induces tumours in nude mice, while mice harbouring transgenic thyroidal PBF expression show hyperplasia and macrofollicular lesions. Our assumption that PBF becomes an oncogene purely through increased expression has been challenged by the recent report of mutations in PBF within the Catalogue of Somatic Mutations in Cancer (COSMIC) database. We therefore sought to determine whether the first 10 PBF missense substitutions in human cancer might be oncogenic. Anisomycin half-life studies revealed that most mutations were associated with reduced protein stability compared to wild-type (WT) PBF. Proliferation assays narrowed our interest to two mutational events which significantly altered cell turnover: C51R and R140W. C51R was mainly confined to the endoplasmic reticulum while R140W was apparent in the Golgi apparatus. Both C51R and R140W lost the capacity to induce cellular migration and significantly reduced cell invasion. Colony formation and soft agar assays demonstrated that, in contrast to WT PBF, both mutants were unable to elicit significant colony formation or anchorage-independent growth. However, C51R and R140W retained the ability to repress radioiodide uptake, a functional hallmark of PBF. Our data reveal new insight into PBF function and confirm that, rather than being oncogenic, mutations in PBF are likely to be passenger effects, with overexpression of PBF the more important aetiological event in human cancer.

Open access

R Formosa, J Borg, and J Vassallo

Pituitary adenomas (PA) represent the largest group of intracranial neoplasms and yet the molecular mechanisms driving this disease remain largely unknown. The aim of this study was to use a high-throughput screening method to identify molecular pathways that may be playing a significant and consistent role in PA. RNA profiling using microarrays on eight local PAs identified the aryl hydrocarbon receptor (AHR) signalling pathway as a key canonical pathway downregulated in all PA types. This was confirmed by real-time PCR in 31 tumours. The AHR has been shown to regulate cell cycle progression in various cell types; however, its role in pituitary tissue has never been investigated. In order to validate the role of AHR in PA behaviour, further functional studies were undertaken. Over-expression of AHR in GH3 cells revealed a tumour suppressor potential independent of exogenous ligand activation by benzo α-pyrene (BαP). Cell cycle analysis and quantitative PCR of cell cycle regulator genes revealed that both unstimulated and BαP-stimulated AHR reduced E2F-driven transcription and altered expression of cell cycle regulator genes, thus increasing the percentage of cells in G0/G1 phase and slowing the proliferation rate of GH3 cells. Co-immunoprecipitation confirmed the interaction between AHR and retinoblastoma (Rb1) protein supporting this as a functional mechanism for the observed reduction. Endogenous Ahr reduction using silencing RNA confirmed the tumour suppressive function of the Ahr. These data support a mechanistic pathway for the putative tumour suppressive role of AHR specifically in PA, possibly through its role as a cell cycle co-regulator, even in the absence of exogenous ligands.

Open access

Ruth T Casey, Benjamin G Challis, Alison Marker, Deborah Pitfield, Heok K Cheow, Ashley Shaw, Soo-Mi Park, Helen L Simpson, and Eamonn R Maher

Open access

Laura C Hernández-Ramírez, Ryhem Gam, Nuria Valdés, Maya B Lodish, Nathan Pankratz, Aurelio Balsalobre, Yves Gauthier, Fabio R Faucz, Giampaolo Trivellin, Prashant Chittiboina, John Lane, Denise M Kay, Aggeliki Dimopoulos, Stephan Gaillard, Mario Neou, Jérôme Bertherat, Guillaume Assié, Chiara Villa, James L Mills, Jacques Drouin, and Constantine A Stratakis

The CABLES1 cell cycle regulator participates in the adrenal–pituitary negative feedback, and its expression is reduced in corticotropinomas, pituitary tumors with a largely unexplained genetic basis. We investigated the presence of CABLES1 mutations/copy number variations (CNVs) and their associated clinical, histopathological and molecular features in patients with Cushing’s disease (CD). Samples from 146 pediatric (118 germline DNA only/28 germline and tumor DNA) and 35 adult (tumor DNA) CD patients were screened for CABLES1 mutations. CNVs were assessed in 116 pediatric CD patients (87 germline DNA only/29 germline and tumor DNA). Four potentially pathogenic missense variants in CABLES1 were identified, two in young adults (c.532G > A, p.E178K and c.718C > T, p.L240F) and two in children (c.935G > A, p.G312D and c.1388A > G, and p.D463G) with CD; no CNVs were found. The four variants affected residues within or close to the predicted cyclin-dependent kinase-3 (CDK3)-binding region of the CABLES1 protein and impaired its ability to block cell growth in a mouse corticotropinoma cell line (AtT20/D16v-F2). The four patients had macroadenomas. We provide evidence for a role of CABLES1 as a novel pituitary tumor-predisposing gene. Its function might link two of the main molecular mechanisms altered in corticotropinomas: the cyclin-dependent kinase/cyclin group of cell cycle regulators and the epidermal growth factor receptor signaling pathway. Further studies are needed to assess the prevalence of CABLES1 mutations among patients with other types of pituitary adenomas and to elucidate the pituitary-specific functions of this gene.

Open access

Jan P Dumanski, Chiara Rasi, Peyman Björklund, Hanna Davies, Abir S Ali, Malin Grönberg, Staffan Welin, Halfdan Sorbye, Henning Grønbæk, Janet L Cunningham, Lars A Forsberg, Lars Lind, Erik Ingelsson, Peter Stålberg, Per Hellman, and Eva Tiensuu Janson

The genetics behind predisposition to small intestinal neuroendocrine tumors (SI-NETs) is largely unknown, but there is growing awareness of a familial form of the disease. We aimed to identify germline mutations involved in the carcinogenesis of SI-NETs. The strategy included next-generation sequencing of exome- and/or whole-genome of blood DNA, and in selected cases, tumor DNA, from 24 patients from 15 families with the history of SI-NETs. We identified seven candidate mutations in six genes that were further studied using 215 sporadic SI-NET patients. The result was compared with the frequency of the candidate mutations in three control cohorts with a total of 35,688 subjects. A heterozygous variant causing an amino acid substitution p.(Gly396Asp) in the MutY DNA glycosylase gene (MUTYH) was significantly enriched in SI-NET patients (minor allele frequencies 0.013 and 0.003 for patients and controls respectively) and resulted in odds ratio of 5.09 (95% confidence interval 1.56–14.74; P value = 0.0038). We also found a statistically significant difference in age at diagnosis between familial and sporadic SI-NETs. MUTYH is involved in the protection of DNA from mutations caused by oxidative stress. The inactivation of this gene leads to specific increase of G:C- > T:A transversions in DNA sequence and has been shown to cause various cancers in humans and experimental animals. Our results suggest that p.(Gly396Asp) in MUTYH, and potentially other mutations in additional members of the same DNA excision-repair pathway (such as the OGG1 gene) might be involved in driving the tumorigenesis leading to familial and sporadic SI-NETs.

Open access

Yuet-Kin Leung, Vinothini Govindarajah, Ana Cheong, Jennifer Veevers, Dan Song, Robin Gear, Xuegong Zhu, Jun Ying, Ady Kendler, Mario Medvedovic, Scott Belcher, and Shuk-Mei Ho

In utero exposure to bisphenol A (BPA) increases mammary cancer susceptibility in offspring. High-fat diet is widely believed to be a risk factor of breast cancer. The objective of this study was to determine whether maternal exposure to BPA in addition to high-butterfat (HBF) intake during pregnancy further influences carcinogen-induced mammary cancer risk in offspring, and its dose–response curve. In this study, we found that gestational HBF intake in addition to a low-dose BPA (25 µg/kg BW/day) exposure increased mammary tumor incidence in a 50-day-of-age chemical carcinogen administration model and altered mammary gland morphology in offspring in a non-monotonic manner, while shortening tumor-free survival time compared with the HBF-alone group. In utero HBF and BPA exposure elicited differential effects at the gene level in PND21 mammary glands through DNA methylation, compared with HBF intake in the absence of BPA. Top HBF + BPA-dysregulated genes (ALDH1B1, ASTL, CA7, CPLX4, KCNV2, MAGEE2 and TUBA3E) are associated with poor overall survival in The Cancer Genomic Atlas (TCGA) human breast cancer cohort (n = 1082). Furthermore, the prognostic power of the identified genes was further enhanced in the survival analysis of Caucasian patients with estrogen receptor-positive tumors. In conclusion, concurrent HBF dietary and a low-dose BPA exposure during pregnancy increases mammary tumor incidence in offspring, accompanied by alterations in mammary gland development and gene expression, and possibly through epigenetic reprogramming.