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GH and sex hormones are critical regulators of body growth and composition, somatic development, intermediate metabolism, and sexual dimorphism. Deficiencies in GH- or sex hormone-dependent signaling and the influence of sex hormones on GH biology may have a dramatic impact on liver physiology during somatic development and in adulthood. Effects of sex hormones on the liver may be direct, through hepatic receptors, or indirect by modulating endocrine, metabolic, and gender-differentiated functions of GH. Sex hormones can modulate GH actions by acting centrally, regulating pituitary GH secretion, and peripherally, by modulating GH signaling pathways. The endocrine and/or metabolic consequences of long-term exposure to sex hormone-related compounds and their influence on the GH-liver axis are largely unknown. A better understanding of these interactions in physiological and pathological states will contribute to preserve health and to improve clinical management of patients with growth, developmental, and metabolic disorders.

BCR-ABL1-STAT5 is an oncogenic signaling pathway in human chronic myelogenous leukemia (CML) and it represents a valid target for anti-CML drug design. Resistance to direct BCR-ABL1 inhibitors is a common clinical issue, so STAT5 inhibition has become an interesting alternative target. In this study, the effects of NPQ-C6, a novel naphtoquinone-coumarin conjugate, were evaluated on human CML-derived K562 cells. Live-Cell Imaging analysis revealed that NPQ-C6 inhibited 2D (IC50AUC = 1.4 ± 0.6 μM) growth of CML cells. NPQ-C6 increased sub-G1 and reduced G0/G1 cell cycle phases in a dose- and time-dependent manner. This effect on cell cycle was related to increased levels of apoptotic nuclei, cleavage of caspase-3, -9, and PARP and annexin V-positive cells. NPQ-C6 increased γH2AX, a double-strand DNA break marker. NPQ-C6 showed a wide range of modulatory effects on cell signaling through an early increased phosphorylation of JNK, P38-MAPK and AKT, and decreased phosphorylation of ERK1/2, BCR-ABL1, and STAT5. NPQ-C6 inhibited expression of c-MYC and PYM-1, two target gene products of BCR-ABL1/STAT5 signaling pathway. Cytokine-induced activation of STAT5/STAT3-dependent transcriptional and DNA binding activities were also inhibited by NPQ-C6. Notably, NPQ-C6 maintained its activity on BCR-ABL1/STAT5/c-MYC/PIM-1 oncogenic pathway in imatinib-resistant cells. Molecular modeling suggested BCR-ABL1 and JAK2 proteins as NPQ-C6 targets. In summary, our data show a novel multikinase modulator that might be therapeutically effective in BCR-ABL1-STAT5-related malignancies.

Human Chronic Myelogenous Leukemia (CML) is a hematological stem cell disorder which is associated with activation of Bcr-Abl-Stat5 oncogenic pathway. Direct Bcr-Abl inhibitors are initially successful for the treatment of CML but over time many patients develop drug resistance. In the present study, the effects of CM363, a novel naphthoquinone (NPQ) derivative, were evaluated on human CML-derived K562 cells. CM363 revealed an effective cell growth inhibition (IC50 = 0.7 ± 0.5 μM) by inducing cancer cells to undergo cell cycle arrest and apoptosis. CM363 caused a dose- and time-dependent reduction of cells in G0/G1 and G2/M phases. This cell cycle arrest was associated with increased levels of cyclin E, pChk1 and pChk2 whereas CM363 downregulated cyclin B, cyclin D3, p27, pRB, Wee1, and BUBR1. CM363 increased the double-strand DNA break marker γH2AX. CM363 caused a time-dependent increase of annexin V-positive cells, DNA fragmentation and increased number of apoptotic nuclei. CM363 triggered the mitochondrial apoptotic pathway as reflected by a release of cytochrome C from mitochondria and induction of the cleavage of caspase-3 and -9, and PARP. CM363 showed multikinase modulatory effects through an early increased JNK phosphorylation followed by inhibition of pY-Bcrl-Abl and pY-Stat5. CM363 worked synergistically with imatinib to inhibit cell viability and maintained its activity in imatinib-resistant cells. Finally, CM363 (10 mg/Kg) suppressed the growth of K562 xenograft tumors in athymic mice. In summary, CM363 is a novel multikinase modulator that offers advantages to circumvent imanitib resistance and might be therapeutically effective in Bcrl-Abl-Stat5 related malignancies.

Microsatellite instability (MSI) and aneuploidy are inversely related phenomena. We tested whether ploidy status influences the clinical impact of MSI in endometrioid endometrial cancer (EEC). We analyzed 167 EECs for MSI and ploidy. Tumors were classified in three categories according to MSI and ploidy status. Associations with clinicopathological and molecular variables, survival, and treatment response were assessed. All MSI tumors (23%) were scored as diploid, and 14% of microsatellite stable (MSS) tumors presented aneuploidy. MSI tumors associated with older age at diagnosis, non-obesity, high histological grade, and advanced surgical stage. MSS-aneuploid tumors also associated with higher grade and advanced stage. In multivariate survival analysis MSI did not influence disease-free survival (DFS) or cancer-specific survival (CSS). However, when just diploid tumors were considered for the analysis, MSI significantly contributed to worse DFS and CSS, and the same was observed for aneuploidy when MSS tumors were analyzed alone. In diploid tumors, a differential response to postoperative radiotherapy (RT) was observed according to MSI, since it predicted poor DFS and CSS in the multivariate analysis. We conclude that ploidy status influences the clinical impact of MSI in EEC. Among diploid tumors those with MSI have poor clinical outcome and respond worse to RT.

Human Chronic Myelogenous Leukemia (CML) is a hematological stem cell disorder which is associated with activation of Bcr-Abl-Stat5 oncogenic pathway. Direct Bcr-Abl inhibitors are initially successful for the treatment of CML but over time many patients develop drug resistance. In the present study, the effects of CM363, a novel naphthoquinone (NPQ) derivative, were evaluated on human CML-derived K562 cells. CM363 revealed an effective cell growth inhibition (IC50 = 0.7 ± 0.5 μM) by inducing cancer cells to undergo cell cycle arrest and apoptosis. CM363 caused a dose- and time-dependent reduction of cells in G0/G1 and G2/M phases. This cell cycle arrest was associated with increased levels of cyclin E, pChk1 and pChk2 whereas CM363 downregulated cyclin B, cyclin D3, p27, pRB, Wee1, and BUBR1. CM363 increased the double-strand DNA break marker γH2AX. CM363 caused a timedependent increase of annexin V-positive cells, DNA fragmentation and increased number of apoptotic nuclei. CM363 triggered the mitochondrial apoptotic pathway as reflected by a release of cytochrome C from mitochondria and induction of the cleavage of caspase-3 and -9, and PARP. CM363 showed multikinase modulatory effects through an early increased JNK phosphorylation followed by inhibition of pY-Bcrl-Abl and pY-Stat5. CM363 worked synergistically with imatinib to inhibit cell viability and maintained its activity in imatinib-resistant cells. Finally, CM363 (10 mg/Kg) suppressed the growth of K562 xenograft tumors in athymic mice. In summary, CM363 is a novel multikinase modulator that offers advantages to circumvent imanitib resistance and might be therapeutically effective in Bcrl-Abl- Stat5 related malignancies., This research has been supported by the Spanish Ministry of Science and Innovation (SAF2009-13296) and MINECO (SAF2012-37344, SAF2014-53526R, and SAF2015-65113-C2-2-R) with the co-funding of European Regional Development Fund (ERDF). This Project has been also supported by Centro Atlántico del Medicamento S.A. (CEAMED; www.ceamedsa.com) and Alfredo Martín-Reyes Foundation (Arehucas)-Canary Islands Foundation for Cancer Research (FICIC).

Aim DNA double strand break (DSB) repair is a central cellular mechanism of the DNA damage response to maintain genomic stability. DSB components are frequently mutated in colorectal cancer with microsatellite instability (MSI). We investigated whether DSB repair is involved in endometrial cancer (EC) with MSI. Methods Mononucleotide microsatellite tracts of 14 genes of the DSB repair system were analysed in a series of 41 EC with MSI. Among these genes, the microcephalin 1 ( MCPH1 / BRIT1 ) has never been tested as target of MSI in tumour series. Results The most frequently mutated gene was DNAPKcs ( n =14, 34%) followed by RAD50 ( n =7, 17%), MRE11 , ATR and BRCA1 ( n =6, 15%), and by CtIP and MCPH1 ( n =5, 12%). While DSB biallelic mutations were infrequent, a high proportion of tumours ( n =30, 73%) presented mutations at some component of the DSB repair pathway, and almost half of them showed alterations at two or more components. Tumours with mutations in two or more genes were significantly associated with advanced grade ( p =0.03) and vascular invasion ( p =0.02) and marginally associated with advanced stage ( p =0.07). Conclusions Our results suggest that in EC, the DSB repair is a relatively common mutational target of MSI and might contribute to tumour progression, and also that MCHP1 may be a novel target gene of MSI.

Purpose To elucidate whether microsatellite instability (MSI) predicts clinical outcome in radiation-treated endometrioid endometrial cancer (EEC). Methods and Materials A consecutive series of 93 patients with EEC treated with extrafascial hysterectomy and postoperative radiotherapy was studied. The median clinical follow-up of patients was 138 months, with a maximum of 232 months. Five quasimonomorphic mononucleotide markers (BAT-25, BAT-26, NR21, NR24, and NR27) were used for MSI classification. Results Twenty-five patients (22%) were classified as MSI. Both in the whole series and in early stages (I and II), univariate analysis showed a significant association between MSI and poorer 10-year local disease-free survival, disease-free survival, and cancer-specific survival. In multivariate analysis, MSI was excluded from the final regression model in the whole series, but in early stages MSI provided additional significant predictive information independent of traditional prognostic and predictive factors (age, stage, grade, and vascular invasion) for disease-free survival (hazard ratio [HR] 3.25, 95% confidence interval [CI] 1.01–10.49; p = 0.048) and cancer-specific survival (HR 4.20, 95% CI 1.23–14.35; p = 0.022) and was marginally significant for local disease-free survival (HR 3.54, 95% CI 0.93–13.46; p = 0.064). Conclusions These results suggest that MSI may predict radiotherapy response in early-stage EEC.

Steroid hormones activate target cells through specific receptors that discriminate among ligands based upon recognition of distinct structural features. For most known steroids, membrane and nuclear receptors co-exist in many target cells. However, while the structure of the nuclear receptors and their function as transcriptional activators of specific target genes is generally well understood, the identity of the membrane receptors remains elusive. Using pharmacological and biochemical approaches, we are beginning to characterize receptors for glucocorticoids and anabolic-androgenic steroids in male rat liver membranes. Male rat liver endoplasmic reticulum contains two steroid binding sites which are functionally related and associated with a 90–134 kDa oligomeric protein: (1) the low-affinity glucocorticoid binding site (LAGS), composed at least in part of two peptides (37 and 53 kDa) that bind glucocorticoids and (2) the stanozolol binding protein (STBP), composed at least in part of three peptides (22, 31, and 55 kDa) that bind the synthetic androgen stanozolol. These steroid binding proteins have many properties different from those of classical nuclear receptors, with the salient differences being a failure to recognize “classical” ligands for nuclear receptors together with marked differences in biochemical properties and physiological regulation. The mechanism of interaction of glucocorticoids with the LAGS can be clearly distinguished from that with STBP. Moreover, STBP shows an extremely narrow pharmacological profile, being selective for ST and its analog, danazol, among more than 100 steroids and non-steroidal compounds that were assayed, including those that are able to displace glucocorticoids from the LAGS. The level of LAGS activity undergoes dramatic variations following changes from the physiological serum levels of thyroid hormones, glucocorticoids, GH, vitamin A, and E2. However, neither thyroid hormones nor GH have a critical role on STBP activity. The STBP is functionally related to LAGS. We have suggested a novel mechanism for STBP whereby membrane-associated glucocorticoid binding activity is targeted by stanozolol (and 16β-hydroxylated stanozolol): stanozolol modulates glucocorticoid activity in the liver through negative allosteric modulation of the LAGS resulting in an effective increase in classical GR-signaling by increasing glucocorticoid availability to the cytosolic GR.

Aromatase (CYP19) converts adrenal and ovarian androgens into estrogens, which supports the growth of estrogen-dependent breast cancers. Anti-aromatase agents are displacing antiestrogens as the first-line treatment for estrogen receptor positive breast cancers. Androgens can act as estrogen precursors, but besides this capability they can also directly act on breast cancer cells by binding to androgen receptors, which are present in the majority of breast cancer specimens. Epidemiological and clinical evidences suggest that higher levels of circulating androgen increase the risk of developing breast cancer. Androgen receptor gene polymorphisms which render the more transcriptionally active receptors have been related to a lower risk of breast cancer. It is currently accepted that androgens act as antiproliferative agents in the presence of estrogens in some breast cancer cell lines. However, emerging evidence suggests that direct androgenic activity might also stimulate cell growth in a subset of estrogen-resistant breast tumors. Here we discuss the supporting evidence which proposes that androgens themselves are actively involved in breast carcinogenesis and its clinical behaviour.

The EPH/EFN family of receptor tyrosine kinases regulates cell adhesion and migration and has an important role in controlling cell positioning in the normal intestinal epithelium. Inactivation of EPHB2 has recently been shown to accelerate tumorigenesis in the colon and rectum, and we have previously demonstrated frequent frameshift mutations (41%) in an A9 coding microsatellite repeat in exon 17 of EPHB2 in colorectal tumors with microsatellite instability (MSI). In this study, we extended these analyses to extracolonic MSI cancers, and found frameshift EPHB2 mutations in 39% (25/64) of gastric tumors and 14% (8/56) of endometrial tumors. Regression analysis of these EPHB2 mutation data on the basis of our previously proposed statistical model identified EPHB2 as a selective target of frameshift mutations in MSI gastric cancers but not in MSI endometrial carcinomas. These results suggest a functional role for EPHB2 in gastric tumor progression, and emphasize the differences between the tumorigenic processes in MSI gastrointestinal and endometrial cancer.

Microsatellite instability (MSI) and mutations in the PTEN gene are among the molecular alterations involved in endometrial carcinogenesis. There is conflicting information regarding to their role in this type of tumor. For this reason, we have studied both molecular lesions in a large population-based series of 205 patients with sporadic endometrial cancer. MSI was found in 41 (20.0%) of the tumors and PTEN mutations were found in 74 (36.1%). There were differences in genotype between tumors with and without MSI. Tumors with MSI showed both a higher frequency of PTEN mutations (58.5% vs. 30.4%) (p=0.002, Fisher's exact test) and a higher number of insertions or deletions (I/D) of one nucleotide within the mononucleotide tracts of the PTEN gene (45.8% vs. 11.4% out of all I/D, p=0.005). Conversely, G:C to A:T transitions in CpG dinucleotides were found mostly in microsatellite stable tumors (57.7% vs. 18.2% out of all single-base substitutions, p=0.037). Overall, 67.6% of tumors with mutated PTEN exhibited multiple mutations or allelic imbalance (AI). Multiple PTEN mutations in the same tumor were more frequent in tumors with MSI (60% vs. 25.7%); by contrast the presence of AI accompanying PTEN mutation was higher in microsatellite stable tumors (74.3% vs. 40%) (p=0.028). In addition, patients with both genetic alterations were diagnosed at more advanced stage of progression (54.2% for MSI vs. 20.0% for MSS, p=0.006), and exhibited a worse prognosis (hazard ratio [95% confidence interval]: 3.0 [1.1-13.1], p=0.034, log-rank test) than patients with only the PTEN gene mutated. Our data suggest that the DNA mismatch repair system status influences: (i) both the frequency and the mutational spectrum of PTEN; (ii) the nature of one of the hits that inactivate this tumor-suppressor gene; and (iii) the clinical condition and behavior of the patients.

The human androgen receptor (AR) gene possesses 2 trinucleotide repeats of CAG and GGN in exon 1. The CAG repeat corresponds to a polyglutamine tract in the N-terminal region of the receptor, that affects its transcriptional efficiency. The GGN repeat codifies for a polyglycine tract, and affects the amount of the AR protein transcribed. The endometrium contains ARs and the androgens have antiproliferative properties in cultured endometrial cancer (EC) cells. Larger CAG repeats of the AR gene give rise to a weaker transcriptional activity and have been found to be associated with endometrial carcinogenesis. The possible involvement of CAG and GGN tracts in the progression of EC is unknown. To study that possibility, we have genotyped both CAG and GGN polymorphisms of the AR gene in tumor tissue genomic DNA from a series of 204 consecutive patients with EC, and analyzed the results with regard to the pathological features and clinical outcome of patients. We classified the alleles as S (shortor= median; S-CAGor=21 repeats; S-GGNor=22 repeats) or L (longmedian). The genotype with both S-CAG repeat alleles (SS-CAG) was more common in patients diagnosed at an early stage (41.6% SS-CAG vs 22.6% SL- and LL-CAG together, p = 0.048) and in tumors that did not invade the vascular space (43.0% SS-CAG vs 26.4% SL- and LL-CAG together, p = 0.034). The genotype with SS-GGN alleles was more common in well-differentiated tumors (41.2% SS-GGN vs 25.2% LS- and LL-GGN together, p = 0.017) and in endometrioid histological subtype tumors (35.3% SS-GGN vs 13.0% SL- and LL-GGN together, p = 0.034). When the genotypes of both repeats coexisting in each tumor specimen were taken into consideration, the relationship between the SS-CAG genotype and early stage remained only in the presence of the SS-GGN genotype (43.9% vs 0%, p = 0.01). No other associations were observed. In univariate survival analysis, patients with short alleles of both repeats (SS-CAG and SS-GGN genotypes simultaneously) had a lower risk of cancer-specific death (p = 0.032, mean follow-up: 63 months). Our data suggests that short CAG or GGN repeats of the AR gene are associated with a more benign condition of traditional prognostic variables in EC.

Our study attempts to determine the prognostic value of the quantitative measurement of the oncoprotein p185Her-2/neu in a group of patients with breast cancer and positive node involvement. In a series of 217 patients with breast cancer and positive nodes in whom the oncoprotein p185 was quantitatively determined by ELISA, we analyzed the clinico-pathological variables including age, menopausal status, tumor size, number of affected nodes, type and histology grade and the molecular variables such as the oestrogen and progesterone receptors (ER and PR, respectively), pS2 and Cathepsin D (CD). Using 260 fmol/mg protein as a cut-off point, 18% of the tumors presented as overexpressing p185. The p185 showed no relationship with any of the clinico-pathological variables studied except that its concentration was elevated in ductal and lobular histology types and in the moderate and poorly differentiated histology grades. With a median follow-up of 50 months (range 1–90), the univariate analysis of disease-free survival (DFS) and overall survival (OS) showed that the histology grade, tumor size, the number of infiltrated nodes, the p185 and the ER were the variables associated with the clinical course of the disease in the patients. In the multivariate analysis, however, only the tumor size, number of affected ganglia, the p185 and the ER remained associated with the clinical progression of the disease. The patients with p185 overexpression had a risk, not only of relapse but also death from the disease, of more than twice that of the patients who had normal p185 concentrations. When the p185 was divided into 3 categories based on ±1 × SD above or below the mean, the patients with high and low p185 showed, in the univariate analysis, a similar relationship with DFS but not with OS. In the multivariate analysis, both with the DFS as with the OS, only a high p185 concentration retained its association with the clinical course of the disease in the patients. Our results suggest that by quantitatively determining (using ELISA) the p185 oncoprotein, groups of cancer patients of high risk could be better identified for more effective clinical management. © 2002 Wiley-Liss, Inc.

The liver of adult mammals contains various classes of polyploid hepatocytes produced by a process that is partially regulated by hormones. However, it is not well understood how the hormones affect the rate of hepatocyte proliferation under physiological conditions. Here we have studied the specific roles of 3,5,3′-triiodothyronine (T3), growth hormone (GH), and sex steroids on the percentage of diploid nuclei in S phase and on the population of liver tetraploid (4C) cell nuclei in several rat model systems. Gonadal steroids had no effect on the S phase but account for gender differences in the 4C nuclei. Hypophysectomy in adult male rats produced a moderate decrease in 4C nuclei that was reversed by treatment with 25 μg T3⋅ kg−1⋅ day−1, whereas treatment with 200 μg human recombinant GH (hGH) ⋅ kg−1⋅ day−1was ineffective. Rats made hypothyroid by methimazole treatment of dams and pups until death showed a low S phase and only 5% of 4C nuclei at 70 days of age. T3significantly increased the S phase 24 h after administration and restored the adult normal level of 4C nuclei after 10 days of treatment. hGH did not affect the 4C nuclei or the S phase in the hypothyroid rats. These results suggest that the processes of hepatocyte proliferation and polyploidization of the rat liver are under endocrine control, with thyroid hormones playing the essential regulatory role.

17β-estradiol (E2) may interfere with endocrine, metabolic, and gender-differentiated functions in liver in both females and males. Indirect mechanisms play a crucial role because of the E2 influence on the pituitary GH secretion and the GHR-JAK2-STAT5 signaling pathway in the target tissues. E2, through its interaction with the estrogen receptor, exerts direct effects on liver. Hypothyroidism also affects endocrine and metabolic functions of the liver, rendering a metabolic phenotype with features that mimic deficiencies in E2 or GH. In this work, we combined the lipid and transcriptomic analysis to obtain comprehensive information on the molecular mechanisms of E2 effects, alone and in combination with GH, to regulate liver functions in males. We used the adult hypothyroid-orchidectomized rat model to minimize the influence of internal hormones on E2 treatment and to explore its role in male-differentiated functions. E2 influenced genes involved in metabolism of lipids and endo-xenobiotics, and the GH-regulated endocrine, metabolic, immune, and male-specific responses. E2 induced a female-pattern of gene expression and inhibited GH-regulated STAT5b targeted genes. E2 did not prevent the inhibitory effects of GH on urea and amino acid metabolism-related genes. The combination of E2 and GH decreased transcriptional immune responses. E2 decreased the hepatic content of saturated fatty acids and induced a transcriptional program that seems to be mediated by the activation of PPARα. In contrast, GH inhibited fatty acid oxidation. Both E2 and GH replacements reduced hepatic CHO levels and increased the formation of cholesterol esters and triacylglycerols. Notably, the hepatic lipid profiles were endowed with singular fingerprints that may be used to segregate the effects of different hormonal replacements. In summary, we provide in vivo evidence that E2 has a significant impact on lipid content and transcriptome in male liver and that E2 exerts a marked influence on GH physiology, with implications in human therapy.

HER-2/neu oncogene status and total cellular p185HER-2 content were simultaneously analyzed in 415 invasive breast-cancer specimens by differential PCR and ELISA respectively. Mathematical analysis of the data led us to establish a cut-off value of 1.7 for the ratio between the intensity of the HER-2/neu gene band and the reference gene band, to consider the HER-2/neu gene amplified, and of 260 fmol/mg protein, to consider p185HER-2 over-expressed. Of the 415 tumors studied, 15% showed a diverse degree of HER-2/neu gene amplification. Of these tumors, 87% showed over-expression of the p185HER-2. Of the remaining 352 specimens that did not display HER-2/neu gene amplification, 97% showed no p185HER-2 over-expression (p < 0.0001). In 40 selected samples with a p185HER-2 level lower than 260 fmol/mg protein, the degree of p185HER-2 phosphorylation was very low or undetectable. Conversely, 38 of 46 selected tumors with a p185HER-2 level higher than 260 fmol/mg protein exhibited a considerable degree of p185HER-2 phosphorylation (p < 0.0001). Our data suggest that: (i) differential PCR and ELISA, which are relatively simple procedures, give similar information on HER-2/neu status in breast cancer; and (ii) given the large series analyzed, the cutoff values established can be considered as safe values for determining whether, in a given tumor, the HER-2/neu oncogene is amplified or p185HER-2 is over-expressed. © 1996 Wiley-Liss, Inc.

Review.-- Open Access.-- et al., GH is main regulator of body growth and composition, somatic development, intermediate metabolism and gender-dependent dimorphism in mammals. The liver is a direct target of estrogens because it expresses estrogen receptors which are connected with development, lipid metabolism and insulin sensitivity, hepatic carcinogenesis, protection from drug-induced toxicity and fertility. In addition, estrogens can modulate GH actions in liver by acting centrally, regulating pituitary GH secretion, and, peripherally, by modulating GHR-JAK2-STAT5 signalling pathway. Therefore, the interactions of estrogens with GH actions in liver are biologically and clinically relevant because disruption of GH signaling may cause alterations of its endocrine, metabolic, and gender differentiated functions and it could be linked to dramatic impact in liver physiology during development as well as in adulthood. Finally, the interplay of estrogens with GH is relevant because physiological roles these hormones have in human, and the widespread exposition of estrogen or estrogen-related compounds in human. This review highlights the importance of these hormones in liver physiology as well as how estrogens modulate GH actions in liver which will help to improve the clinical use of these hormones. © 2012 by the authors; licensee MDPI, Basel, Switzerland., Research program in the author lab has been supported by grants from the Spanish Ministry of Science and Innovation with the funding of European Regional Development Fund-European Social Fund (SAF2003-02117 and SAF2006-07824) and Canary Islands Government (ACIISI; PI2007/033). M.M-G is recipient of a fellowship from University of Las Palmas de Gran Canaria (Spain).

GH participates in the regulation of the expression of several hepatic proteins, some of which are subject to multihormonal control. We have previously shown the participation of glucocorticoids and thyroid hormones in the regulation of the hepatic low affinity glucocorticoid-binding sites (LAGS). Here, we provide evidence that also implicates GH in the endocrine control of the LAGS through the use of several animal models, all of them having a very low or undetectable plasma GH level: the hypothyroid (TX), the hypophysectomized, and the GH-deficient Lewis-derived dwarf rat. In dwarf rats, the level of LAGS was only 35% of that found in normal Lewis rats. Treatment of these rats with human (h) GH significantly increased the LAGS level in a dose-response manner. In TX rats, hGH treatment provoked a significant increase in the LAGS level (from 0.9 +/- 0.2 to 7.2 +/- 0.8 pmol/mg protein), so that it represented about 65% of the level found in intact animals. In both hypothyroid-adrenalectomized and hypophysectomized rats, the isolated effect of hGH was not as pronounced as in TX or dwarf rats; however, a potentiation of the effect of hGH was observed when this hormone was injected together with corticosterone acetate. On the other hand, when hGH, T3, and corticosterone acetate were given in combination to hypophysectomized rats, hGH and T3 behaved as agonists of the LAGS induction at T3 doses lower than or equal to 0.1 microgram/100 g BW and as antagonists at T3 doses higher than this. When T4 was used instead of T3, this hormone was capable of potentiating the effect of hGH at doses lower than or equal to 1.5 micrograms/100 g BW. From these results we conclude that 1) GH as well as thyroid and glucocorticoid hormones participate in the endocrine regulation of the LAGS; and 2) under physiological conditions, it is conceivable that GH, thyroid hormones, and glucocorticoids act synergistically in the endocrine regulation of the LAGS.

The low-affinity glucocorticoid binding sites (LAGS) are entities present in the microsomal fraction of the rat liver, capable of binding several glucocorticoids and progesterone with low affinity. The present work focuses on the demonstration that estradiol exerts a powerful stimulatory effect on the LAGS concentration. For this purpose, we studied the effect of this hormone in immature, hypothyroid, and hypophysectomized rats, three experimental models which present a very low level of LAGS. In all of them, estradiol showed ability to significantly increase the level of LAGS. The positive results obtained in hypophysectomized rats point to a direct action of estradiol on the liver. In immature rats, the estradiol induction of the LAGS was shown to be especially slow, 3-4 days after estradiol administration being necessary to obtain a significant rise in the level of LAGS. Moreover, the dose of estradiol necessary to obtain the LAGS induction in these rats (0.5 mg/100 g body weight) was clearly supraphysiological. From these data we concluded that: (A) estradiol is a powerful stimulator of the LAGS concentration, its effect probably being exerted directly on the liver; and (B) to elicit its effect, estradiol does not need the participation of other hormones known to be implicated in the endocrine regulation of the LAGS.

The endometrial stroma plays a decisive role in sustaining the gland epithelium along the menstrual cycle, and in preparing the microenvironment that allows embryo implantation. The stroma undergoes important changes during the menstrual cycle that affects both the cell number and differentiation. These changes are regulated by both estrogen and progesterone. Stromal sarcomas are extremely rare, occuring much less than any other uterine tumor. Their origin and biology are poorly understood. The purpose of this work was to try to learn more about the stromal physiology, and also to ascertain whether the stromal sarcoma has characteristics of hormone dependence. We studied the presence of estrogen receptors (ER), progesterone receptors (PR) and the stress-responsive protein of 27K (srp27, a protein first described as an estrogen-induced 24K protein in MCF-7 cells) in both normal stroma and stromal sarcoma. The ER and PR were measured by exchange assays. The srp 27 was studied both by Western-blot and by IHC by means of specific monoclonal antibodies. The stromal sarcomas studied showed a high concentration of both ER (96 to 116 fmol/mg prot.) and PR (565 to 995 fmol/mg prot.). These amounts of ER and PR were higher than the mean found in normal endometrium during the proliferative phase (43 and 637 fmol/mg prot., respectively), and much higher than that of the secretory phase (17 and 229 fmol/mg prot., respectively). The srp27 characterized by Western-blot in both the normal stroma and stromal sarcoma was found to be similar to the srp27 of breast cancer. The IHC results showed a very low expression of srp27 in the stroma during the proliferative phase that increases when the endometrium enters the secretory phase. The low-malignancy grade stromal sarcomas showed abundant expression of srp27, but the high-malignancy grade sarcomas showed no expression of srp27. The obtained results prove the stroma capability to express the srp27. A negative correlation between malignancy of stromal tumors and srp27 expression was found. The presence of ER and PR in some stromal sarcomas proves that they have characteristics of hormone responsiveness. These findings suggest that ER and PR assays should be routinely performed in stromal sarcomas as well as in endometrial adenocarcinomas, and also that antiestrogenic drugs might be considered for the treatment of ER and PR positive stromal sarcomas.

The low affinity glucocorticoid binding sites (LAGS) have been described and partially characterized in both the nuclei and microsomes of rat liver. The LAGS concentration is under endocrine regulation, as proved by their decrease after adrenalectomy and their almost complete disappearance after hypophysectomy. This article describes new data that also implicate the thyroid hormones in the endocrine regulation of LAGS. The LAGS were measured by [3H]dexamethasone exchange assay in crude microsome suspensions of rat liver. Propylthiouracil-induced hypothyroidism (TX) provoked a 90% reduction in the LAGS levels with respect to the control value. The administration of T3 to TX rats was able to completely restore the LAGS level. On the other hand, adrenalectomy (ADX) provoked a 50% decrease in LAGS levels, and this effect could be reverted by treatment with corticosterone acetate. TX rats that were also adrenalectomized (TX-ADX) showed a LAGS level similar to that of the TX rats. However, treatment of these rats with T3 was much less effective than in TX rats. A complete restoration of the LAGS level in TX-ADX rats could be achieved only with a combined treatment of corticosterone acetate plus T3. Similar results to those obtained in TX-ADX rats were also obtained in immature or hypophysectomized rats, two experimental models known to possess very low or undetectable levels of LAGS. From these findings we conclude that: 1) thyroid hormones, as well as glucocorticoids, play an important role in the regulation of the LAGS level; 2) glucocorticoids and thyroid hormones act synergistically in the endocrine regulation of LAGS; and 3) the results obtained in the hypophysectomized rats point to a direct action of glucocorticoids and T3 on the LAGS level of the rat liver.

The human androgen receptor (AR) gene possesses two trinucleotide repeats of CAG and GGN in exon-1. The GGN repeat affects the amount of AR protein translated, while the CAG repeat affects the efficiency of AR transcriptionaly. In this study, we have genotyped these polymorphic tracts in a representative sample of 557 Caucasian adult individuals (314 women and 243 men) from the Canary Islands, Spain (the ENCA Study), and investigated their association with fasting serum levels of lipids, glucose and insulin. The number of CAG repeats in women (expressed as the average length of the two alleles) was inversely correlated with serum levels of LDL-cholesterol (Spearman rho=-0.179; P

The exon 1 of the human androgen receptor (AR) gene contains two length polymorphisms of CAG (polyglutamine) and GGN (polyglycine). “In vitro” experiments suggest that the larger GGN repeats provide a lower AR-protein yield, whereas the larger CAG repeats decrease the AR transcriptional activity, both decreasing the AR signalling intensity. Here we have tested such possibilities in human prostatic cancer (CaP) specimens. We used 72 archival samples of radical prostatectomy. Parallel slides were used for AR protein or PSA immunohistochemistry, and for genotyping studies. Polymorphisms were genotyped by PCR, fragment length analysis and sequencing selected samples. The AR staining was positively correlated with the Gleason score ( r = 0.320; P = 0.005), but it was not correlated to CAG or GGN repeat length or PSA staining. The number of GGN repeats was negatively correlated to the intensity of PSA staining ( r = −0.243; P = 0.04). Combination of short alleles of both tracts was significantly higher in: the heavier stained tertiles for PSA ( P = 0.03) and AR ( P = 0.06); and in the subgroup of samples having a Gleason score of 7 or higher ( P = 0.021). The results support the hypothesis that the shorter alleles of CAG and GGN repeats in the AR gene are associated to an increased AR signalling intensity in human prostate cancer, and with more aggressive forms of the disease.

The exon 1 of the human androgen receptor gene (AR) contains both CAG (polyglutamine) and GGN (polyglycine) repeat length polymorphisms. Large CAG repeats have been related to an increased risk of breast cancer (BC), whereas the influence of the GGN repeats is still unclear. Here, we have studied how the length of CAG and GGN repeats is associated with the risk of BC in a population from Tenerife (Canary Islands, Spain). The study was carried out on 257 woman diagnosed with BC and 393 controls, nesting in the ‘CDC of the Canary Islands’ cohort study. The AR CAG and GGN genotyping was performed by means of PCR amplification with specific fluorescently labelled primers followed by a capillary electrophoresis. The allelic distribution of CAG and GGN polymorphisms was similar in cases and controls. The mean of short and long CAG and GGN alleles did not show differences between cases and controls and the same was true when the average length of both CAG alleles (CAGn) and GGN alleles (GGNn) was considered. However, when CAGn and GGNn were categorised using 22 and 24 repeats as the cut-off point, respectively, significant differences between cases and controls were observed. The CAGn > 22 repeats were more frequent in cases than in controls, being associated with an increased risk of BC (OR = 1.49; CI95% = 1.06–2.09; p = 0.021). No significant differences were found for categorised GGNn. For CAGn/GGNn combinations, the highest BC risk was found to be associated with the CAGn > 22/GGNn ⩾ 24 combination (OR = 2.47; CI95% = 1.37–4.46; p = 0.003). In conclusion, our results indicate that longer CAGn/GGNn combinations increase the risk of BC and suggest that CAG and GGN AR polymorphisms should be considered in order to assess the BC risk.

Our study attempts to determine the prognostic value of the quantitative measurement of the oncoprotein p185(Her-2/neu) in a group of patients with breast cancer and positive node involvement. In a series of 217 patients with breast cancer and positive nodes in whom the oncoprotein p185 was quantitatively determined by ELISA, we analyzed the clinico-pathological variables including age, menopausal status, tumor size, number of affected nodes, type and histology grade and the molecular variables such as the oestrogen and progesterone receptors (ER and PR, respectively), pS2 and Cathepsin D (CD). Using 260 fmol/mg protein as a cut-off point, 18% of the tumors presented as overexpressing p185. The p185 showed no relationship with any of the clinico-pathological variables studied except that its concentration was elevated in ductal and lobular histology types and in the moderate and poorly differentiated histology grades. With a median follow-up of 50 months (range 1-90), the univariate analysis of disease-free survival (DFS) and overall survival (OS) showed that the histology grade, tumor size, the number of infiltrated nodes, the p185 and the ER were the variables associated with the clinical course of the disease in the patients. In the multivariate analysis, however, only the tumor size, number of affected ganglia, the p185 and the ER remained associated with the clinical progression of the disease. The patients with p185 overexpression had a risk, not only of relapse but also death from the disease, of more than twice that of the patients who had normal p185 concentrations. When the p185 was divided into 3 categories based on +/-1 x SD above or below the mean, the patients with high and low p185 showed, in the univariate analysis, a similar relationship with DFS but not with OS. In the multivariate analysis, both with the DFS as with the OS, only a high p185 concentration retained its association with the clinical course of the disease in the patients. Our results suggest that by quantitatively determining (using ELISA) the p185 oncoprotein, groups of cancer patients of high risk could be better identified for more effective clinical management.

Total cytosolic cathepsin D (Cat D) levels were estimated by an immunoradiometric assay in a series of 156 consecutive patients with surgical stages I–III primary endometrial adenocarcinoma. Simultaneously, the tissue content of both oestrogen (ER) and progesterone (PR) receptors, and p185HER-2/neu, DNA content (ploidy), and the fraction of S-phase cells (S-phase) were also estimated. Tumoral Cat D content ranged from 0 to 243 pmol mg−1 protein (median 44 pmol mg−1 protein) and was not associated with any of the established clinicopathological and biological prognostic variables, with the exception of a weak positive correlation with the tumoral p185HER-2/neu levels. Univariable analysis performed on a subset of 97 patients, followed for a minimum of 2 years or until death, showed that patient age at diagnosis, high histological grade, advanced surgical stage, vascular invasion, positive peritoneal cytology, low levels of Cat D, negative ER and PR status, aneuploidy, and high S-phase were predictive of the presence of persistent or recurrent disease. However, multivariable analysis revealed that only histological grade, surgical stage, Cat D and PR were significantly associated with the patient's outcome. From these findings, we conclude that Cat D is an independent prognostic factor in endometrial adenocarcinoma, its low levels being associated with a worse clinical outcome. © 1999 Cancer Research Campaign

The total cellular p185(HER-2/neu) protein (p185) content was measured by ELISA in 346 invasive primary breast cancers, and the results were compared with those of estrogen (ER) and progesterone (PR) receptors, pS2 and Cathepsin D (Cat D) content. At a cut-off level of 260 fmol/mg protein, 53 of the 346 tumors (15%) were p185-positive. A significant positive correlation was observed between p185 levels and those of Cat D, and a weaker, though significant, positive correlation with ER, and pS2 levels, but not with those of PR. However, when only the 293 p185-negative tumors were considered, the correlation between p185 and ER improved substantially, and statistical significance was reached for PR. p185-positive tumors exhibited lower ER and PR content and higher Cat D content than p185-negative tumors. The pS2 content, in contrast, did not undergo significant variation. Tumors considered to be p185-positive were significantly more frequently positive for Cat D at the cut-off of 45 pmol/mg protein, and were more frequently negative for ER and/or PR, but only significant at the cut-off of 15 fmol/mg or higher for both steroid receptors. Finally, p185 status was not associated with menopausal status, tumor size, axillary-lymph-node invasiveness or distant metastases. These results suggest that 260 fmol/mg protein as the cut-off for p185 allows the identification of a tumoral sub-population with a more aggresive phenotype.

Rat liver membranes contain Low-affinity glucocorticoid binding sites (LAGS), capable of binding with low affinity (Kd approximately 100 nM) endogenous glucocorticoids. Unlike the glucocorticoid receptor (GR), the LAGS level undergoes abrupt changes throughout life. The investigation of these changes may be useful in determining whether the LAGS are involved in the cellular response to glucocorticoids. For this purpose, we have studied glucocorticoid induction of tyrosine aminotransferase (TAT), and its relationship with the LAGS level in adrenalectomized and fasted rats of different ages. No significant differences in the GR level, or in its Kd and activation, were observed among rats of 1, 3, and 12 months of age. On the other hand, the LAGS level showed an important variation with age, from almost undetectable in 1-month-old rats, to a maximum value in 3-month-old rats. With respect to TAT activity, an increase with age in the threshold of response to dexamethasone (DEX) administration was observed. The smallest dose of DEX capable of provoking a significant TAT induction rose from 0.1 microgram/kg body wt. in 1-month-old rats to 10 micrograms/kg body wt. in 12-month-old rats. However, the smallest dose of DEX able to elicit the maximal response was 10 micrograms/kg body wt. in all the assayed ages. This dose provoked a 40% decrease in the GR level, but did not significantly modify the LAGS content. From these results, we conclude that there is an age-related change in the threshold of response to DEX that cannot be explained by the GR-glucocorticoid interaction. The possibility that the LAGS modulate the cell response to glucocorticoids arises from the coincidence of this change with that observed in the LAGS concentration throughout life.

// Sergio Alonso 1, 2 , Yuichi Dai 1, 3, 4 , Kentaro Yamashita 1 , Shina Horiuchi 1 , Tomoko Dai 1, 3 , Akihiro Matsunaga 1 , Rosa Sanchez-Munoz 1 , Cristina Bilbao-Sieyro 5 , Juan Carlos Diaz-Chico 5 , Andrei V. Chernov 6 , Alex Y. Strongin 6 , Manuel Perucho 1, 2, 7 1 Tumor Initiation and Maintenance Program, Sanford-Burnham Medical Research Institute (SBMRI), La Jolla, California, USA 2 Institute of Predictive and Personalized Medicine of Cancer (IMPPC), IGTP, Badalona, Barcelona, Spain 3 Dept. of Pathology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan 4 Dept. of Diagnostic Pathology, Tsukuba Memorial Hospital, Tsukuba, Ibaraki, Japan 5 Dept. of Biochemistry and Molecular Biology, Cancer Research Institute of The Canary Islands, University of Las Palmas de Gran Canaria, Spain 6 Cancer Research Center, Sanford-Burnham Medical Research Institute (SBMRI), La Jolla, California, USA 7 Institucio Catalana de Recerca i Estudis Avancats (ICREA), Barcelona, Spain Correspondence to: Manuel Perucho, e-mail: mperucho@imppc.org Keywords: KRAS mutations, TP53 mutations, MGMT , O 6 -methylguanine-DNA methyltransferase, ADAMTS14 , CRC, colorectal cancer Received: November 28, 2014 Accepted: December 04, 2014 Published: February 02, 2015 ABSTRACT Somatic hypermethylation of the O 6 -methylguanine-DNA methyltransferase gene ( MGMT ) was previously associated with G > A transition mutations in KRAS and TP53 in colorectal cancer (CRC). We tested the association of MGMT methylation with G > A mutations in KRAS and TP53 in 261 CRCs. Sixteen cases, with and without MGMT hypermethylation, were further analyzed by exome sequencing. No significant association of MGMT methylation with G > A mutations in KRAS, TP53 or in the whole exome was found ( p > 0.5 in all comparisons). The result was validated by in silico comparison with 302 CRCs from The Cancer Genome Atlas (TCGA) consortium dataset. Transcriptional silencing associated with hypermethylation and stratified into monoallelic and biallelic. We also found a significant clustering ( p = 0.001) of aberrant hypermethylation of MGMT and the matrix metalloproteinase gene ADAMTS14 in normal colonic mucosa of CRC patients. This suggested the existence of an epigenetic field defect for cancerization disrupting the methylation patterns of several loci , including MGMT or ADAMTS14 , that may lead to predictive biomarkers for CRC. Methylation of these loci in normal mucosa was more frequent in elder ( p = 0.001) patients, and particularly in African Americans ( p = 1 × 10 −5 ), thus providing a possible mechanistic link between somatic epigenetic alterations and CRC racial disparities in North America.