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Most sporadic colorectal cancer reflects acquired mutations in the adenomatous polyposis coli (APC) tumor suppressor gene, while germline heterozygosity for mutant APC produces the autosomal dominant disorder Familial Adenomatous Polyposis (FAP) with a predisposition to colorectal cancer. In these syndromes, loss of heterozygosity (LOH) silences the remaining normal allele of APC, through an unknown mechanism, as the initiating step in transformation. Guanylyl cyclase C receptor (GUCY2C) and its hormones, uroguanylin and guanylin, have emerged as a key signaling axis opposing mutations driving intestinal tumorigenesis. Indeed, uroguanylin and guanylin are among the most commonly repressed genes in colorectal cancer. Here, we explored the role of APC heterozygosity in mechanisms repressing hormone expression which could contribute to LOH. In genetic mouse models of APC loss, uroguanylin and guanylin expression were quantified following monoallelic or biallelic deletion of the Apc gene. Induced biallelic loss of APC repressed uroguanylin and guanylin expression. However, monoallelic APC loss in Apcmin/+ mice did not alter hormone expression. Similarly, in FAP patients, normal colonic mucosa (monoallelic APC loss) expressed guanylin while adenomas and an invasive carcinoma (biallelic APC loss) were devoid of hormone expression. Thus, uroguanylin and guanylin expression by normal intestinal epithelial cells persists in the context of APC heterozygosity and is lost only after tumor initiation by APC LOH. These observations reveal a role for loss of the hormones silencing the GUCY2C axis in tumor progression following biallelic APC loss, but not in mechanisms creating the genetic vulnerability in epithelial cells underlying APC LOH initiating tumorigenesis. [ABSTRACT FROM AUTHOR]

Head and neck squamous cell carcinoma is one of the leading cancers in terms of incidence and mortality. However, no reliable marker till date accurately predicts its progression when altered in healthy tissues. The study aims to identify alleles of microsatellites adjacent to important cell cycle regulatory, tumor suppressor genes altered in early head and neck lesions, viz. RBSP3, LIMD1 and CDC25A, which undergo frequent deletion and can be used for population screening and early detection. DNA for tumors and normal tissues was isolated from 143 patients in different stages of head and neck squamous cell carcinoma. The size of microsatellite present in normal tissues and their deletion in the corresponding tumor was identified, along with the correlation of expression in normal epithelium with respect to allele size. The results revealed a range of alleles (CA9 to CA32) for the different microsatellites of the genes in normal tissues. The larger alleles were significantly deleted with differential deletion of alleles observed in tumors, except for LIMD1, in which the smaller allele was significantly deleted. In normal tissues, some alleles represented as stable alleles with high prevalence, while in tumours, specific sizes showed greater propensity for deletion. However, similar expression of the proteins in normal epithelium adjacent to tumors was observed despite variations in allele size, possibly due to the location of the microsatellites. Thus, those alleles when present in normal tissues and undergoing persistent deletion in tumours could be used as markers for screening and early identification of populations at risk of developing head and neck lesions. [ABSTRACT FROM AUTHOR]

Background: Late-onset hypogonadism (LOH) presents with low serum testosterone (TT) levels and sexual and nonsexual symptoms. Erectile dysfunction affects a man's self-esteem and as a result partner relationship and quality of life.Objectives: To investigate the andrological clinical profile outcomes of testosterone therapy (TTh) in men (n = 88) with symptomatic LOH complaints and symptoms.Main Outcome Measures: Erectile function was assessed using the International Index of Erectile Function-5 questionnaire at baseline and at 6 and 12 months of TTh. In addition, penile length was measured at baseline and 12 months. We also evaluated nocturnal penile tumescence (NPT, using RigiScan) and blood flow of cavernous arteries (penile Doppler ultrasonography) at baseline and 12 months of TT.Materials and Methods: Eighty-eight LOH men (Mage 51.1 years) with erectile dysfunction, all with serum TT <10.4 nmol/L before TTh. Patients received intramuscular long-acting testosterone undecanoate for 12 months.Results: Following TTh, in all patients, serum TT levels were restored within 3 months to normal levels. Compared with baseline values, erectile function significantly improved at 6 (mean score increase 1.95) and 12 months (mean score increase 2.16). No significant changes in penile length were observed. NPT significantly improved at 12 months in terms of both the frequency (mean increase 1.27 times) and duration of rigidity (mean increase 5.12 min). As regards the blood flow of the cavernous arteries, we observed a significant improvement (decrease of 1.16 cm/s) and end diastolic velocity of the penile arteries.Conclusion: TTh in men with LOH resulted in improvement of the erectile function, NPT, and to some extent the blood flow of the cavernous arteries. [ABSTRACT FROM AUTHOR]

Purpose: To investigate a possible relation between penile Doppler ultrasound examination (PDUE) parameters and efficacy of chronic therapy with tadalafil (TAD) combined with a protocol of aerobic physical activity (PA) in patients with late onset hypogonadism (LOH).Methods: The study evaluated 30 patients consecutively enrolled with LOH and erectile dysfunction which present contraindication to hormonal replacement therapy for concomitant prostate disease. These patients were subjected to a combined protocol with phosphodiesterase V selective inhibitors (TAD 5 mg daily) and aerobic PA. Results: After three months, we observed significant improvements in erectile function [IIEF-5, median (IQR) = 13.0 (7.0–18.0) versus 6.0 (5.0–6.75);p < 0.01] and of the main metabolic [homeostatic model assessment index, median (IQR) = 2.5 (1.62–3.37) versus 3.0 (2.0–3.75);p < 0.01; body mass index, median (IQR) = 27.0 (24.0–28.75) versus 27.5 (24.0–29.5)] and vascular parameters [peak systolic velocity, median (IQR) = 29.5 (24.25–31.0) versus 28.0 (23.0–24.25); acceleration time, median (IQR) = 114 (105.25–134.0) versus 115.0 (106.5–134.0)], assessed by PDUE. Conclusion: PA in association with phosphodiesterase V inhibitors could compensate the effects of hypogonadism on erectile function and facilitate the clinical response to these drugs even in the absence of adequate serum concentrations of total testosterone. [ABSTRACT FROM PUBLISHER]

According to the Fifth National Wilms Tumor Study (NWTS-5), tumor-specific loss of heterozygosity (LOH) for chromosomes 1p and 16q identifies a subset of patients with Wilms tumor (WT) who despite having favorable histology (FH) have a significantly increased risk of relapse and death. We aimed to find out 1p and 16q LOH frequencies in patients with FH-WT as well as its correlation to survival outcome and epidemiologic and clinical characteristics. Data of patients with FH-WT presenting to the National Cancer Institute, Egypt, were retrospectively analyzed. Paraffin blocks were tested for 1p and 16q LOH using polymorphic loci that span the minimal regions of LOH at this area. The study included 100 patients with a median age of 5 years. Thirty-nine patients (39%) showed LOH at 1p (n= 14), 16q (n= 13), or both (n= 12). LOH was most frequently encountered in patients above 10 years (5/5), advanced stages disease (80% of stage V and 50% of stages IV and III each). The 3-year overall survival (OS) and event-free survival (EFS) were significantly lower in patients with double LOH (75% and 50%, respectively), followed by 16q (92% and 54%), in comparison with 1p (93% each) and negative LOH (97% and 100%) cases, respectively (p= 0.001). Combined LOH (1p+16q), followed by 16q LOH alone, was predictive of poorer outcome and was associated with lower OS and EFS in patients with FH-WT. Our results showed a higher-risk disease that would suggest the need for an intensified upfront therapy in this group of patients. [ABSTRACT FROM PUBLISHER]

Objective: This study assessed the efficacy and safety of testosterone replacement therapy (TRT) in aging Japanese men with late-onset hypogonadism (LOH). Methods: This study included 50 (median age: 57.7 years) Japanese men with LOH, who were consecutively enrolled and treated with TRT for at least six months at our institution. We evaluated the following measurements before and after six months of treatment with TRT as follows: blood tests, prostate volume, residual urine volume, self-ratings for International Index of Erectile Function 5 (IIEF-5), International Prostate Symptom Score (IPSS), Self-Rating Depression Scale (SDS), Aging Male Symptom (AMS) and the Medical Outcomes Study 8-item Short-Form health survey (SF-8). Results: Following six months of TRT, the levels of testosterone, red blood cells, hemoglobin and hematocrit were significantly increased from baseline, while total cholesterol level was significantly decreased from baseline. Furthermore, TRT led to a significant increase in IIEF-5 score and a significant decrease in IPSS score. Of 30 men who were diagnosed with depression at baseline, only 11 men (36.7%) were still suffering from depression after TRT, and SDS scores were significantly decreased from baseline at month six. Treatment with TRT led to a significant decrease in all scores of the AMS scale as well as a significant improvement in all scores of the SF-8 survey, with the exception of the bodily pain score. Conclusion: These findings suggest that TRT is an effective and safe treatment for aging Japanese men with LOH. TRT improved depressive symptoms as well as health-related quality of life. [ABSTRACT FROM AUTHOR]

Long-standing gastroesophageal reflux disease can result in transformation of the normal squamous lining of the esophagus into columnar epithelium (with goblet cells). This condition, Barrett's esophagus (BE), is considered a risk factor for esophageal cancer (EAC) and may be the cause of the increased incidence of EAC over the last few decades. Currently, endoscopy with biopsies revealing dysplasia is the best predictor for neoplastic progression in patients with BE. However, the use of more sophisticated imaging techniques and biomarkers with or without histological assessment may be helpful in more accurate prediction of malignant transformation in these patients. New approaches to the evaluation of BE such as epigenetics, miRNA analysis, detection of DNA content abnormalities and loss of heterozygosity have great potential to shed light on the complex gastroesophageal reflux disease -BE-EAC sequence. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate plasma cytokine levels after treatment with saikokaryukotsuboreito (SKRBT), which is a herbal medicine, or androgen replacement treatment (ART), for patients with late-onset hypogonadism (LOH)-related symptoms. Thirty-one patients over 40 years of age with LOH-related symptoms were included in this study. SKRBT was given orally three times daily to a total of 7.5 g/day for 15 eugonadal patients and ART was give to 16 hypogonadal patients by intramuscular injection of testosterone enanthate at 125 mg each time every 2 weeks. Plasma levels of testosterone and 18 cytokines, as well as LOH-related symptoms scored according to the Aging Males' Symptoms (AMS) scale, were compared before and more than 2 months after treatment. In the ART group, the total AMS score was decreased and testosterone was increased significantly after treatment. No cytokine variables were altered significantly after the treatment. In the SKRBT group, although the total AMS score was significantly decreased, testosterone did not change. From the evaluation of cytokines, a significant increase was found in interleukin (IL)- 8, IL-13, interferon-γγ and tumour necrosis factor-αα. We conclude that SKRBT might improve LOH-related symptoms in eugonadal patients through the beneficial effect of cytokines, a mechanism that is quite different from ART. [ABSTRACT FROM AUTHOR]

Introduction. In addition to hormone replacement therapy, non-hormonal therapy, particularly Japanese traditional herbal medicine (Kampo), has been used to alleviate the various symptoms of female menopause. The efficacy and safety of Japanese traditional herbal medicine for male late-onset hypogonadism (LOH) are investigated. Methods. One hundred fifty-one patients with LOH were treated via the administration of Japanese traditional herbal medicine. The most appropriate Japanese traditional herbal medicine was administered to patients according to their pathogenic alteration. After 4 weeks, the clinical efficacy was evaluated based on improvement of LOH symptoms and the score of the simplified menopausal index (SMI). Additionally, predictive factors of efficacy of Japanese traditional herbal medicine were analyzed. Results. Among 151 patients with LOH, 63 (41.8%) achieved both relief from LOH symptoms and normalized SMI score (Excellent response group), whereas 44 (29.1%) achieved either relief from LOH symptoms or normalized SMI score (Fair). However, 44 (29.1%) patients displayed neither relief from LOH symptoms nor normalized SMI score (Poor). Adverse reactions were observed only in four (2.6%) patients. Patients displaying excess conditions and mild LOH symptoms appeared to be superior candidates for Japanese traditional herbal medicine. Conclusion. Japanese traditional herbal medicine is an effective and safe treatment for LOH. [ABSTRACT FROM AUTHOR]

Objective: Present study deals with LOH and MSI in FHIT gene and p53 expression in GBC, CC, XGC, and normal GB to elucidate the role of FHIT gene in gall bladder cancer. Methods: Five microsatellite markers D3S1217, D3S1300, D3S1313, D3S1600, and D3S2757, were selected. Results: Among GBC cases the frequency of MSI-H and LOH was 17.5% and 27.5%, respectively. Significant difference was found between GBC and normal GB (p = .02), and GBC and CC groups (p= .002) when LOH was compared. Conclusions: Our results suggested CC might act as a preinvasive stage in the pathogenesis of GBC. [ABSTRACT FROM AUTHOR]

We have analyzed allelic loss of the short arm of chromosome 9 in 39 head and neck cancers using 13 polymorphic markers and found two deletions of hot spots at 9p21 and 9p24. Loss of heterozygosity was detected at least at one locus in 28 of 39 cases (71.8%). P16, a well-known tumor suppressor gene, is considered to be a target for deletion of the 9p21 region. However, novel frequent chromosomal deletion and a candidate tumor suppressor gene, BRM at the 9p24 region, were detected. Moreover, comparison of clinicopathological variables demonstrated that loss of heterozygosity at the BRM locus was associated with a worse prognosis. [ABSTRACT FROM AUTHOR]

Objective. Telomere shortening is thought to be associated with genetic instability. The purpose of this study was to measure telomere length in a series of Barrett's adenocarcinomas (BAs), focusing on the telomere/centromere fluorescent intensity ratio (TCR) with tissue quantitative fluorescent in situ hybridization (Q-FISH). Material and methods. A total of 11 cases of BA were evaluated for upper esophagus (UE), lower esophagus (LE), Barrett's mucosa (BM), BA, and gastric cardiac mucosa (GC). Q-FISH was performed using two kinds of peptide nucleic acid probe, specific for telomeres and centromeres. The sections were analyzed with a CCD camera and original software (Tissue Telo) for measuring TCR. In addition, Laser Capture Microdissection and GeneScan were implemented for evaluation of genetic instability. Results. The TCR values in BM and, to a lesser extent, BA were significantly lower than those in the other tissues, particularly in heterozygosity (LOH)-positive cases. However, no significant difference was evident between microsatellite instability (MSI)-positive and -negative groups. Conclusions. In our study of BA series, telomere length appeared to change with the degree of histological atypia, with decreases linked to LOH. [ABSTRACT FROM AUTHOR]

Lung cancer is the most lethal carcinoma worldwide. Mutations of p53 inactivation of p16INK4a, and overexpression of cylclins E, A and B are independently associated with poor prognoses of patients, while the prognostic value of cyclin D1 or RB expression is inconclusive. Cyclin D binding myb-like protein 1 (Dmp1) encodes a DNA binding protein that receives signals from oncogenic Ras and functions as a tumor suppresor by activating the Arf0150p53 pathway. Dmp1 has been shown to be haplo-insufficient for tumor suppression in mouse models including K-ras-mediated lung carcinogenesis. The human DMP1 gene is located on chromosome 7q21, and our recent results revealed that the hDMP1 gene is deleted, but not mutated or silenced, in approximately 40 % of human non-small-cell lung carcinomas. These cases typically retained wild-type ARF and p53 and expressed very low levels of the hDMP1 protein. Thus, hDMP1 loss could be a novel diagnostic marker for non-small-cell lung carcinomas. [ABSTRACT FROM AUTHOR]

Deletions on chromosome 6q are frequently reported in hematological malignancies. However, their biological or prognostic impact has not yet been clarified. This study analyzed loss of heterozygosity (LOH) at chromosome 6q and compared the LOH findings in pediatric precursor T lymphoblastic lymphoma (T-LBL) with the LOH findings in precursor-T lymphoblastic leukemia (T-ALL). For LOH analyses, a set of 25 microsatellite-markers on 6q14-q24 were examined. All patients were treated uniformly according to ALL-BFM-type treatment-strategy. A total of 1671 markers were successfully analyzed from 108 T-LBL patients. LOH was detected in 21 T-LBL patients. There was clear association between LOH at 6q and an increased risk of relapse. In comparison, 3109 markers were successfully analyzed from 127 T-ALL-patients. LOH was detected in 16 patients, but was not associated with increased relapse-rate. The localization of the common LOH regions identified for T-LBL and T-ALL samples did not overlap. Therefore patterns of LOH at 6q and the prognostic impact of LOH differ between T-ALL and T-LBL. These results hint at biologic differences between the two diseases. [ABSTRACT FROM AUTHOR]

We show that N-acetyltransferase 2 (NAT2) loss of heterozygosity can be targeted in >4% of colorectal cancers with the use of a small molecule. We identify and describe the effect of a compound that impairs the growth of colorectal tumors with slow NAT2 activity by half when compared to wild-type. [ABSTRACT FROM AUTHOR]

Deletion of chromosome 6q has frequently been observed in natural killer (NK) cell lymphomas. The aim of this study, is to localize the commonly affected region in chromosome 6q and to compare the frequency of loss of heterozygosity (LOH) between the peripheral T and NK cell lymphomas. Eight cases of peripheral T cell lymphomas, not otherwise characterized (PTCL-NOC), and 5 cases of nasal-type NK/T cell lymphomas were enrolled for the study. Twelve polymorphic markers covering the regions from 6q13 to 6q24, according to the Entrez Database (National Center for Biotechnology Information, NIH, Bethesta, MD), were used for LOH analysis. Results showed LOH at least one locus on chromosome 6q was observed in all cases. Of the informative cases, the overall frequency of LOH for each marker ranged from 8.3 to 58.3%. NK/T cell lymphomas showed a higher frequency of LOH compared to the PTCL ( 47.44±12.39 vs. 30.89±11.97% ). The average frequency of LOH was 31.93±16.04% in stages I+II of the disease, whereas the average was 45.78±4.15% in stages III+IV. The most frequently involved regions were at markers D6S434 (5 of 8 informative cases, 62.5%) on chromosome 6q16.3 in the PTCL, D6S302 (4 of 5 cases, 80%) on chromosome 6q21 and D6S287 on 6q22.3 (4 of 5 cases, 80%) in the NK/T cell lymphoma. In conclusion, LOH of chromosome 6q is more common in nasal-type NK/T cell lymphoma than PTCL. The difference between the commonly lost region of chromosome 6q in NK/T cell lymphoma and that in PTCL suggests that different tumor suppressor genes are involved in the genetic evolution pathway of these two diseases. [ABSTRACT FROM AUTHOR]

Susceptibility to urethan-induced pulmonary adenomas (PA) in mice is under polygenic control. To analyze these traits in detail, we generated a set of recombinant inbred (RI) mouse strains, called SMXA, from an intercross between PA-susceptible A/Jand resistant SM/J, and established a strain distribution pattern (SDP) table of 158 marker loci for SMXA RI strains. From the SDP table, it was possible to estimate the allele for 4 known PA susceptibility (Pas) loci in all members of SMXA RI strains. We compared combinations of Pas loci alleles with the data of number of PA induced by urethan. One of the RI strains, SMXA24, showed extremely low PA numbers, whereas they had the A/J-derived alleles at all 4 Pas loci. F1 hybrids of SMXA24 and A/Jdeveloped as few PA as SMXA24 on exposure to urethan. To confirm the hypothesis that SMXA24 has dominant PA resistance gene(s), we examined a backcross generation to A/J for multiplicity of PA. A preliminary genome scan followed by quantitative trait locus analysis revealed two resistance loci, one on mouse chromosome 11 (MMU11) (logarithm of odds [LOD] score 4.35) and another on MMU12 (LOD score 6.47). They were named Par1 and Par3, respectively. Both loci were epistatic to Pas1, the major susceptibility loci on MMU6. We next asked if such dominant resistance loci play some role in human lung cancer by studying possible loss of heterozygosity (LOH) at syntenic chromosomal segments in 79 human lung cancers, including 30 adenocarcinomas, 25 squamous cell carcinomas (SQ), and 24 small cell carcinomas (SCC). The map positions of Par1 and Par3 correspond to human 17q11–23 and 14q11–24. Of 30 adenocarcinomas, LOH was found in 53% at 17q and in 30% at 14q. For both SQ and SCC, LOH in 17q were about 10%, but LOH in 14q was about 30% to 42%. Therefore, a gene in 17q seemed to be selective for adenocarcinomas, probably at the level of the target cell. In contrast, another gene in 14q affected all 3 types of lung carcinomas, suggesting it is related to the progression of lung tumors in general. A comparative approach may provide useful information for understanding human cancers. [ABSTRACT FROM AUTHOR]