Allelic Loss of the Active X Chromosome During Bladder Carcinogenesis

Mapping cancer biology in space: applications and perspectives on spatial omics for oncology

Technologies to decipher cellular biology, such as bulk sequencing technologies and single-cell sequencing technologies, have greatly assisted novel findings in tumor biology. Recent findings in tumor biology suggest that tumors construct architectures that influence the underlying cancerous mechanisms. Increasing research has reported novel techniques to map the tissue in a spatial context or targeted sampling-based characterization and has introduced such technologies to solve oncology regarding tumor heterogeneity, tumor microenvironment, and spatially located biomarkers. In this study, we address spatial technologies that can delineate the omics profile in a spatial context, novel findings discovered via spatial technologies in oncology, and suggest perspectives regarding therapeutic approaches and further technological developments.

The androgen receptor in bladder cancer

Bladder cancer is the ninth most common cancer worldwide with a striking sex-based difference in incidence. Emerging evidence indicates that the androgen receptor (AR) might promote the development, progression and recurrence of bladder cancer, contributing to the observed sex differences. Targeting androgen-AR signalling has promise as potential therapy for bladder cancer and helps to suppress progression of this disease. In addition, the identification of a new membrane AR and AR-regulated non-coding RNAs has important implications for bladder cancer treatment. The success of human clinical trials of targeted-AR therapies will help in the development of improved treatments for patients with bladder cancer.

The Hypothesis of the Prolonged Cell Cycle in Turner Syndrome

Turner syndrome (TS) is a chromosomal disorder that is caused by a missing or structurally abnormal second sex chromosome. Subjects with TS are at an increased risk of developing intrauterine growth retardation, low birth weight, short stature, congenital heart diseases, infertility, obesity, dyslipidemia, hypertension, insulin resistance, type 2 diabetes mellitus, metabolic syndrome, and cardiovascular diseases (stroke and myocardial infarction). The underlying pathogenetic mechanism of TS is unknown. The assumption that X chromosome-linked gene haploinsufficiency is associated with the TS phenotype is questioned since such genes have not been identified. Thus, other pathogenic mechanisms have been suggested to explain this phenotype. Morphogenesis encompasses a series of events that includes cell division, the production of migratory precursors and their progeny, differentiation, programmed cell death, and integration into organs and systems. The precise control of the growth and differentiation of cells is essential for normal development. The cell cycle frequency and the number of proliferating cells are essential in cell growth. 45,X cells have a failure to proliferate at a normal rate, leading to a decreased cell number in a given tissue during organogenesis. A convergence of data indicates an association between a prolonged cell cycle and the phenotypical features in Turner syndrome. This review aims to examine old and new findings concerning the relationship between a prolonged cell cycle and TS phenotype. These studies reveal a diversity of phenotypic features in TS that could be explained by reduced cell proliferation. The implications of this hypothesis for our understanding of the TS phenotype and its pathogenesis are discussed. It is not surprising that 45,X monosomy leads to cellular growth pathway dysregulation with profound deleterious effects on both embryonic and later stages of development. The prolonged cell cycle could represent the beginning of the pathogenesis of TS, leading to a series of phenotypic consequences in embryonic/fetal, neonatal, pediatric, adolescence, and adulthood life.

Cytologically targeted next-generation sequencing: a synergy for diagnosing urothelial carcinoma

INTRODUCTION

Cytology and cystoscopy are used to detect urothelial carcinoma (UC), but together they still fail to detect some UC cases and are not suitable for screening asymptomatic individuals. Mutations are present in more than 98% of UC, mutations have therapeutic significance, and they can be detected by next generation sequencing (NGS) in urine samples. We review the role of NGS in UC detection.

MATERIALS AND METHODS

Comprehensive literature review on UC genetics, economics of NGS, and previous reports of UC detection by NGS.

RESULTS

The raw costs of NGS have decreased to about 14,000 base pairs per penny, making it appear economically feasible to use NGS widely. Reported NGS assays fall short of predicted sensitivity. Decreased sensitivity is attributed to a low frequency of mutant alleles in many urine samples. Attempts to increase the percentage of mutant alleles, by using cell-free urinary DNA, or by using cell sorting and microfluidics, have been unsuccessful or remain unproven. However, cytologic examination can immediately enable NGS: Urine cytologies with sufficient proportions of abnormal cells could be directly triaged to NGS with high sensitivity for UC detection. For cases with a low proportion of abnormal cells, cytologically targeted microdissection of cells for NGS should maintain sensitivity and decrease sequencing costs. Cytologically targeted urothelial cells for NGS could allow a screening test for low grade UC.

CONCLUSIONS

Cytology is immediately poised to allow NGS to improve the diagnosis of UC, allowing NGS to be an ancillary test for atypical cytologies, and potentially allowing a screening test for low-grade UC.

Role of the androgen receptor in urothelial cancer

Men have had a substantially higher risk of developing bladder cancer than women. This has prompted research on androgen-mediated androgen receptor (AR) signaling in urothelial cancer. Indeed, increasing preclinical evidence indicates that AR activation correlates with the promotion of urothelial carcinogenesis and tumor outgrowth. In this article, we summarize and discuss available data suggesting the involvement of androgens and the AR pathway in the development and progression of urothelial cancer. Although precise mechanisms for the functions of AR and related signals in urothelial cells remain far from being fully understood, current observations may offer effective chemopreventive and therapeutic approaches for urothelial cancer. Clinical application of various anti-AR therapies available for AR-dependent prostate cancer to urothelial cancer patients is thus anticipated.

Androgen Receptor Signaling in Bladder Cancer

Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in urothelial carcinogenesis as well as tumor growth. While the precise mechanisms of the functions of the androgen receptor in urothelial cells remain far from being fully understood, current evidence may offer chemopreventive or therapeutic options, using androgen deprivation therapy, in patients with bladder cancer.

Laser capture microdissection: Big data from small samples

Any tissue is made up of a heterogeneous mix of spatially distributed cell types. In response to any (patho) physiological cue, responses of each cell type in any given tissue may be unique and cannot be homogenized across cell-types and spatial co-ordinates. For example, in response to myocardial infarction, on one hand myocytes and fibroblasts of the heart tissue respond differently. On the other hand, myocytes in the infarct core respond differently compared to those in the peri-infarct zone. Therefore, isolation of pure targeted cells is an important and essential step for the molecular analysis of cells involved in the progression of disease. Laser capture microdissection (LCM) is powerful to obtain a pure targeted cell subgroup, or even a single cell, quickly and precisely under the microscope, successfully tackling the problem of tissue heterogeneity in molecular analysis. This review presents an overview of LCM technology, the principles, advantages and limitations and its down-stream applications in the fields of proteomics, genomics and transcriptomics. With powerful technologies and appropriate applications, this technique provides unprecedented insights into cell biology from cells grown in their natural tissue habitat as opposed to those cultured in artificial petri dish conditions.

The emerging role of the androgen receptor in bladder cancer

Men are three to four times more likely to get bladder cancer than women. The gender disparity characterizing bladder cancer diagnoses has been investigated. One hypothesis is that androgen receptor (AR) signaling is involved in the etiology and progression of this disease. Although bladder cancer is not typically described as an endocrine-related malignancy, it has become increasingly clear that AR signaling plays a role in bladder tumors. This review summarizes current findings regarding the role of the AR in bladder cancer. We discuss work demonstrating AR expression in bladder cancer and its role in promoting formation and progression of tumors. Additionally, we discuss the therapeutic potential of targeting the AR in this disease.

Involvement of the Androgen and Glucocorticoid Receptors in Bladder Cancer

Bladder cancer is encountered worldwide having been associated with a host of environmental and lifestyle risk factors. The disease has a male to female prevalence of 3 : 1. This disparity has raised the possibility of the androgen receptor (AR) pathway being involved in the genesis of the disease; indeed, research has shown that AR is involved in and is likely a driver of bladder cancer. Similarly, an inflammatory response has been implicated as a major player in bladder carcinogenesis. Consistent with this concept, recent work on anti-inflammatory glucocorticoid signaling points to a pathway that may impact bladder cancer. The glucocorticoid receptor- (GR-) α isoform has an important role in suppressing inflammatory processes, which may be attenuated by AR in the development of bladder cancer. In addition, a GR isoform that is inhibitory to GRα, GRβ, is proinflammatory and has been shown to induce cancer growth. In this paper, we review the evidence of inflammatory mediators and the relationship of AR and GR isoforms as they relate to the propensity for bladder cancer.

Primary leiomyosarcoma of a horseshoe kidney in a woman with Turner syndrome: a case report

Background

Turner syndrome is characterized by complete or partial X-chromosome monosomy and has various clinical features, including horseshoe kidney. Leiomyosarcoma is an extremely rare tumor that accounts for only 0.1% of all invasive renal tumors.

Case presentation

A 50-year-old Japanese woman presented at a community hospital with a chief complaint of abdominal pain. Computed tomography revealed a horseshoe kidney with a hypovascular tumor (size, 9 × 7 cm) showing calcification in the upper pole of the right kidney. Open right heminephrectomy and division of the isthmus were performed. Histological examination revealed alternating fascicles of spindle cells with blunt ended non-tapering nuclei and eosinophilic cytoplasm. The tumor had high mitotic activity with a mitotic count of 8 mitoses/10 high-power fields. On the basis of these findings, we diagnosed the patient as having leiomyosarcoma.

Conclusion

Primary leiomyosarcoma of the horseshoe kidney in a patient with Turner syndrome is a very rare occurrence.

The role of the androgen receptor in the development and progression of bladder cancer

Men are at a higher risk of developing bladder cancer than women. Since bladder cancer cell lines and tissues were found to express the androgen receptor, efforts have been made to inspect whether androgen-mediated androgen receptor signals are implicated in bladder carcinogenesis as well as cancer progression. Mounting evidence supports the view that bladder cancer is a member of the endocrine-related tumors and may clearly explain the gender-specific difference in the incidence. However, the underlying mechanisms of how androgen receptor signals regulate bladder cancer growth are still far from fully characterized. Moreover, it remains controversial whether the androgen receptor pathway always plays a dominant role in bladder cancer progression. In this review, we summarize the available data on the involvement of androgen receptor signaling in bladder cancer. In particular, current evidence demonstrating the stimulatory effects of androgens on tumor progression or, more convincingly, tumorigenesis via the androgen receptor pathway may offer great potential for androgen deprivation as a therapeutic or chemopreventive option in patients with bladder cancer.

Bladder cancer: translating molecular genetic insights into clinical practice

Transitional cell (urothelial) carcinoma of the bladder is the second most common urologic malignancy and is one of the best understood neoplasms, with relatively well-defined pathogenetic pathways, natural history, and tumor biology. Conventional clinical and pathologic parameters are widely used to grade and stage tumors and to predict clinical outcome of transitional cell carcinoma; but the predictive ability of these parameters is limited, and there is a lack of indices that could allow prospective assessment of risk for individual patients. In the last decade, a wide range of candidate biomarkers representing key pathways in carcinogenesis have been reported to be clinically relevant and potentially useful as diagnostic and prognostic molecular markers, and as potential therapeutic targets. The use of molecular markers has facilitated the development of novel and more accurate diagnostic, prognostic, and therapeutic strategies. FGFR3 and TP53 mutations have been recognized as key genetic pathways in the carcinogenesis of transitional cell carcinoma. FGFR3 appears to be the most frequently mutated oncogene in transitional cell carcinoma; its mutation is strongly associated with low tumor grade, early stage, and low recurrence rate, which confer a better overall prognosis. In contrast, TP53 mutations are associated with higher tumor grade, more advanced stage, and more frequent tumor recurrences. These molecular markers offer the potential to characterize individual urothelial neoplasms more completely than is possible by histologic evaluation alone. Areas in which molecular markers may prove valuable include prediction of tumor recurrence, molecular staging of transitional cell carcinoma, detection of lymph node metastasis and circulating cancer cells, identification of therapeutic targets, and prediction of response to therapy. With accumulating molecular knowledge of transitional cell carcinoma, we are closer to the goal of bridging the gap between molecular findings and clinical outcomes. Assessment of key genetic pathways and expression profiles could ultimately establish a set of molecular markers to predict the biological nature of tumors and to establish new standards for molecular tumor grading, classification, and prognostication. The main focus of this review is to discuss clinically relevant biomarkers that might be useful in the management of transitional cell carcinoma and to provide approaches in the analysis of molecular pathways that influence the clinical course of bladder cancer.

Constitutional aneuploidy and cancer predisposition

Constitutional aneuploidies are rare syndromes associated with multiple developmental abnormalities and the alterations in the risk for specific cancers. Acquired somatic chromosomal aneuploidies are the most common genetic aberrations in sporadic cancers. Thus studies of these rare constitutional aneuploidy syndromes are important not only for patient counseling and clinical management, but also for deciphering the mechanisms by which chromosomal aneuploidy affect cancer initiation and progression. Here we review the major constitutional aneuploidy syndromes and suggest some general mechanisms for the associated cancer predisposition.

The effect of smoking on the male excess of bladder cancer: a meta-analysis and geographical analyses

Smoking is considered the primary risk factor for bladder cancer. Although smoking prevalence and bladder cancer incidence vary around the world, bladder cancer is on average 4 times more common in males than in females. This article describes the observed male-female incidence ratio of bladder cancer for 21 world regions in 2002 and 11 geographical areas during the time period 1970-1997. A meta-analysis, including 34 studies, was performed to ascertain the increased risk for bladder cancer in males and females when smoking. The summary odds ratios (SORs) calculated in the meta-analysis were used to estimate the male-female incidence ratio of bladder cancer that would be expected for hypothetical smoking prevalence scenarios. These expected male-female incidence ratios were compared with the observed ratios to evaluate the role of smoking on the male excess of bladder cancer. The male-female incidence ratio of bladder cancer was higher than expected worldwide and over time, based on a smoking prevalence of 75% in males, 10% in females and an increased risk (SOR) of bladder cancer associated with smoking of 4.23 for males and 1.35 for females, respectively. This implied that, at least in the Western world, smoking can only partially explain the difference in bladder cancer incidence. Consequently, other factors are responsible for the difference in bladder cancer incidence.

Cancer incidence in women with Turner syndrome in Great Britain: a national cohort study

BACKGROUND

Turner syndrome, one of the most common cytogenetic abnormalities, is characterised by complete or partial X-chromosome monosomy. Cancer risks in women with Turner syndrome have not been clearly established. We aimed to compare the risk of cancer in women with this syndrome with that of the general population.

METHODS

We formed a national cohort of 3425 women who were cytogenetically diagnosed with Turner syndrome in Great Britain between 1959 and 2002. Identifying information for these patients was sent to the National Health Service Central Register (NHSCR) for England and Wales and to the NHSCR for Scotland. Individuals who were identified on this register were followed-up for cancer incidence. Standardised incidence ratios (SIRs) and 95% CIs were calculated on the basis of the number of cancers observed compared with that expected based on national incidence rates. Cumulative risk estimates were obtained by use of the Kaplan-Meier method.

FINDINGS

A total of 58,299 person-years were accrued during the study, with a mean of 17.0 years (SD 8.6) follow-up per patient. 73 malignancies other than non-melanoma skin cancer occurred (SIR 0.9 [95% CI 0.7-1.2]). Risks were significantly increased for tumours of the CNS (n=13; 4.3 [2.3-7.4]), especially for meningioma (n=7; 12.0 [4.8-24.8]) and childhood brain tumours (n=3; 10.3 [2.1-30.1]), and for cancers of the bladder and urethra (n=5; 4.0 [1.3-9.2]) and eye (n=2; 10.5 [1.3-37.9]), compared with the general population. However, the risk of breast cancer was significantly decreased (n=10; 0.3 [0.2-0.6]). The SIR for cutaneous melanoma was 2.2 (95% CI 1.0-4.4; n=8), and one of the ocular cancers was a melanoma. The risk of corpus uteri cancer was significantly increased at ages 15-44 years (n=3; 8.0 [1.6-23.2]). During follow-up, five women, all with a Y-chromosome lineage, developed gonadoblastoma of the ovary, corresponding to a cumulative risk of 7.9% (95% CI 3.1-19.0) by age 25 years in this group.

INTERPRETATION

This study shows that, in addition to having an increased risk of gonadoblastoma, women with Turner syndrome seem to be at increased risk for meningioma and childhood brain tumours, and possibly bladder cancer, melanoma, and corpus uteri cancer, but are at a decreased risk for breast cancer. Reasons for these risks might relate to genetic and hormonal factors or to the effects of hormonal treatments given to women with Turner syndrome.

Adrenal myelolipomas show nonrandom X-chromosome inactivation in hematopoietic elements and fat: support for a clonal origin of myelolipomas

Myelolipomas are defined as mature fat associated with hematopoietic elements, often found in the adrenal gland. The question of whether the hematopoietic cells are truly "normal" has not been evaluated extensively. In this study, we evaluated histologic, immunohistochemical features and comparisons of X-chromosome inactivation patterns in 19 myelolipomas. Formalin-fixed, paraffin-embedded tissue from 19 myelolipomas was stained with hematoxylin and eosin and immunostained with monoclonal antibodies against CD138, CD34, CD117, CD42a, hemoglobin, myeloperoxidase, collagen IV, and nerve growth factor receptor. Histologic evaluation included estimates of overall cellularity of hematopoietic tissue, estimates of cellularity in the areas of highest concentration of hematopoietic tissue, myeloid to erythroid ratio, and numbers of megakaryocytes. X-chromosome inactivation analysis was performed on myelolipomas from 11 female patients by polymerase chain reaction. Myelolipomas showed wide variation in cellularity within the lesion (5% to 90%) with no correlation with the patient's age. All the myelolipomas demonstrated normal trilineage hematopoiesis and cellular morphology, with few early myeloid precursors, as evidenced by negativity for CD117 and only rare positivity for CD34 antibodies. Most of the myelolipomas (14/18) had markedly increased megakaryocytes compared with normal marrows. The majority of myelolipomas also had a stromal composition and vascular patterns that were different from those of normal bone marrow. X-chromosome inactivation studies demonstrated nonrandom X-chromosome inactivation in 8/11 myelolipomas from female patients. Myelolipomas are morphologically different from the normal bone marrow. The majority of myelolipomas also have nonrandom X-chromosome inactivation, suggesting a clonal origin for these tumors.

Five-alpha-reductase expression in benign and malignant urothelium: Correlation with disease characteristics and outcome

OBJECTIVES

To evaluate 5-alpha-reductase (5alphaR) expression in benign and malignant urothelium and to assess the relationship between 5alphaR expression and tumor stage, tumor grade, and clinical outcome in patients with urothelial carcinoma/transitional cell carcinoma.

METHODS

We performed immunohistochemistry for 5alphaR on 53 urothelial specimens from 36 patients with transitional cell carcinoma treated at our institution between June 2002 and July 2003. For each tumor and the adjacent nontumor urothelium, a semiquantitative staining score was calculated. We used t tests and analysis of variance to compare the staining score across groups. Kaplan-Meier and logistic regression analyses were performed to assess the relationship between 5alphaR expression and clinical outcome.

RESULTS

5alphaR was expressed throughout the non-neoplastic urothelium. Nontumor urothelium had greater mean staining scores than did tumor specimens (160.1 versus 105.5, P <0.01). Low staining scores were associated with high grade (P <0.05), Stage pT3, pT4, and pTis (P <0.05), and disease progression (P <0.05). A staining score less than the median was a risk factor for progression (odds ratio 6.2, P <0.01) on univariate regression analysis. Patients with a staining score less than the median had a greater likelihood of disease progression (log-rank P <0.05) and cause-specific mortality (log-rank P <0.05).

CONCLUSIONS

We demonstrated 5alphaR expression in human urothelium and found that expression is decreased in transitional cell carcinoma in relation to tumor grade and stage. Decreased 5alphaR expression was associated with disease progression and cause-specific mortality.

X-Linked Dominant Growth Suppression of Transplanted Tumors in C57BL/6J-scid Mice

Tumor susceptibility, angiogenesis, and immune response differ between mouse strains. We, therefore, examined the growth rates of tumor xenografts in three genetically isolated strains of severe combined immunodeficient mice (C.B-17, C57BL/6J, and C3H). Tumors grew at significantly reduced rates in the C57BL/6J-scid strain. Engrafting bone marrow from the C57BL/6J-scid strain onto C.B-17-scid mice did not transfer the slow-growing tumor phenotype to the recipient mice; this counters the supposition that the slow-growing tumor phenotype is caused by a greater immune response to the xenograft in the C57BL/6J-scid strain. To establish the inheritance pattern of the slow-growing tumor phenotype, we reciprocally crossed C.B-17-scid mice and C57BL/6J-scid mice. Tumor growth was suppressed in all of the F1 progeny except the male mice derived from the cross between C.B-17-scid female and C57BL/6J-scid male mice. The F1 male mice that received the X chromosome from the C.B-17 strain displayed a fast-growing tumor phenotype. These results confirm that there are significant strain differences in capacity to support the growth of tumor xenografts. In addition, these results reveal the existence of a dominant allele involved in host suppression of tumor growth on the X chromosome of C57BL/6J mice.