Embryonic stem cell transcription factor signatures in the diagnosis of primary and metastatic germ cell tumors

New insights on testicular cancer prevalence with novel diagnostic biomarkers and therapeutic approaches

BACKGROUND

Testicular cancer (TC), comprising merely 1% of male neoplasms, holds the distinction of being the most commonly encountered neoplasm among young males.

RECENT FINDINGS

Most cases of testicular neoplasms can be classified into two main groups, namely germ cell tumors representing approximately 95% of the cases, and sex cord-stromal tumors accounting for about 5% of the cases. Moreover, its prevalence is on the rise across the globe. TC is a neoplastic condition characterized by a favorable prognosis. The advent of cisplatin-based chemotherapeutic agents in the latter part of the 1970s has led to a significant enhancement in the 5-year survival rate, which presently surpasses 95%. Given that TC is commonly detected before reaching the age of 40, it can be anticipated that these individuals will enjoy an additional 40-50 years of life following successful treatment. The potential causes of TC are multifactorial and related to different pathologies. Accurate identification is imperative to guarantee the utmost efficacious and suitable therapy. To a certain degree, this can be accomplished through the utilization of blood examinations for neoplastic indicators; nonetheless, an unequivocal diagnosis necessitates an evaluation of the histological composition of a specimen via a pathologist.

CONCLUSION

TC is multifactorial and has various pathologies, therefore this review aimed to revise the prenatal and postnatal causes as well as novel diagnostic biomarkers and the therapeutic strategies of TC.

Clinical Significance of Overexpression of Oct4 in Advanced Stage Gallbladder Carcinoma

BACKGROUND

Oct4 has critical role in maintaining pluripotency, proliferative potential, and self-renewal capacity in embryonic stem and germ cells. Although Oct4 has been shown to be upregulated in many cancers, its clinical significance in gallbladder carcinoma is poorly understood.

METHODS

We studied the expression profile of Oct4 in 61 GBC and 30 chronic cholecystitis (as control) using real time RT-PCR, western blotting, and immunohistochemistry. The expression data was correlated with clinico-pathological parameters. The diagnostic utility was assessed through ROC curve, and prognostic value was analyzed by Kaplan-Meier method.

RESULTS

Oct4 was significantly upregulated at mRNA as well as protein levels. The higher mRNA expression shows significant association with late stage, late T stage, and higher grade of tumor. A significant positive correlation was also observed with stage, T stage, and tumor grade. Sum score analysis of protein expression shows positive correlation with stage and the presence or absence of gallstone in tumor samples. The ROC curve analysis revealed the moderate diagnostic potential of Oct4. Kaplan-Meier analysis showed that patients having higher expression of Oct4 were having low mean survival compared with the patients with lower Oct4 expression.

CONCLUSION

In conclusion, our data suggests that higher expression of Oct4 may serve as potential biological indicator for tumor aggressiveness and poor prognosis of GBC.

Overexpression of SOX2 Gene by Histone Modifications: SOX2 Enhances Human Prostate and Breast Cancer Progression by Prevention of Apoptosis and Enhancing Cell Proliferation

INTRODUCTION

SOX2 plays a crucial role in tumor development, cancer stem cell maintenance, and cancer progression. Mechanisms of SOX2 gene regulation in human breast and prostate cancers are not established yet.

METHODS

SOX2 expression in prostate and breast cancer tissues and cell lines was determined by qRT-PCR, Western blot, and immunochemistry, followed by the investigation of pro-tumorigenic properties like cell proliferation, migration, and apoptosis by gene knockdown and treatment with epigenetic modulators and ChIP.

RESULTS

Prostate and breast cancer tissues showed very high expression of SOX2. All cancer cell lines DU145 and PC3 (prostate) and MCF7 and MDA-MB-231 (breast) exhibited high expression of SOX2. Inhibition of SOX2 drastically decreased cell proliferation and migration. Epigenetic modulators enhanced SOX2 gene expression in both cancer types. DNA methylation pattern in SOX2 promoter could not be appreciably counted for SOX2 overexpression. Activation of SOX2 gene promoter was due to very high deposition of H3K4me3 and H3K9acS10p and drastic decrease of H3K9me3 and H3K27me3.

CONCLUSION

Histone modification is crucial for the overexpression of SOX2 during tumor development and cancer progression. These findings show the avenue of co-targeting SOX2 and its active epigenetic modifier enzymes to effectively treat aggressive prostate and breast cancers.

An update on diagnostic tissue-based biomarkers in testicular tumors

Testicular cancer is rare overall but comprises the most common solid malignancy diagnosed in young men aged ∼20-40 years. Most testicular neoplasms generally fall into 2 broad categories: germ cell tumors (GCTs; ∼95%) and sex cord-stromal tumors (SCSTs ∼5%). Given the relative rarity of these tumors, diagnostic biomarkers are highly relevant for their diagnosis. Over the past several decades, diagnostic biomarkers have improved dramatically through targeted immunohistochemical and molecular characterization. Despite these recent advances, most markers are not perfectly sensitive or entirely specific. Therefore, they need to be used in combination and interpreted in context. In this review, we summarize tissue-based biomarkers relevant to the pathologist, with a focus on practical diagnostic issues that relate to testicular GCT and SCST.

HCV and tumor-initiating stem-like cells

Neoplasms contain tumor-initiating stem-like cells (TICs) that are characterized by increased drug resistance. The incidence of many cancer types have trended downward except for few cancer types, including hepatocellular carcinoma (HCC). Therefore mechanism of HCC development and therapy resistance needs to be understood. These multiple hits by hepatitis C virus (HCV) eventually promotes transformation and TIC genesis, leading to HCC development. This review article describes links between HCV-associated HCC and TICs. This review discusses 1) how HCV promotes genesis of TICs and HCC development; 2) how this process avails itself as a novel therapeutic target for HCC treatment; and 3) ten hall marks of TIC oncogenesis and HCC development as targets for novel therapeutic modalities.

Differential expression of preferentially expressed antigen in melanoma (PRAME) in testicular germ cell tumors - A comparative study with SOX17

The accurate identification of different components in testicular germ cell tumors (GCT) is essential for tailoring treatment and informing the clinical prognosis. PRAME (preferentially expressed antigen in melanoma), a member in the family of cancer testis antigens, plays critical roles in regulating pluripotency and suppressing somatic/germ cell differentiation in seminomas (SEM). To investigate the potential diagnostic value of PRAME in testicular GCT, here we comparatively examined the expression patterns of PRAME and SOX17 by immunohistochemistry in both pure and mixed GCT. Tissue microarrays constructed from 66 pure or mixed GCT were examined, including 25 seminomas (13 pure and 12 mixed), 35 embryonal carcinomas (EC; 7 pure and 28 mixed), 23 teratomas (TER; 10 pure and 13 mixed), 15 yolk sac tumors (YST; 1 pure and 14 mixed), and 5 choriocarcinomas (CC; 1 pure and 4 mixed), with 11 germ cell neoplasia in situ (GCNIS) and 6 normal testicular tissue as controls. The expression levels of PRAME or SOX17 were evaluated by a scoring system counting for intensity and extent of staining. PRAME nuclear expression was present in 92% (23/25) of SEM, including all 13 pure SEM, and 10 out of 12 seminomatous component of mixed GCT. In contrast, all EC and TER were completely negative for PRAME, and focal expression was demonstrated in 33.3% of YST and 20% of CC. As for SOX17, 96% of SEM and 73% of YST stained positively, whereas EC and CC were negative. Focal nuclear positivity was identified in the epithelial cell component of 17.4% (4/23) of TER. We found the sensitivity of PRAME to detect SEM to be comparable to SOX17, although SOX17 staining is more diffuse and stronger in the majority of cases. The specificity of PRAME for SEM appeared to be superior to that of SOX17 (92% versus 81%). In conclusion, PRAME is preferentially expressed in SEM or within the seminomatous component of mixed GCT with only focal variable expression in YST and CC, but shows no expression in EC and TER. These findings suggest that PRAME can be explored as a diagnostic marker for SEM.

OUP accepted manuscript

The pathways of gametogenesis encompass elaborate cellular specialization accompanied by precise partitioning of the genome content in order to produce fully matured spermatozoa and oocytes. Transcription factors are an important class of molecules that function in gametogenesis to regulate intrinsic gene expression programs, play essential roles in specifying (or determining) germ cell fate and assist in guiding full maturation of germ cells and maintenance of their populations. Moreover, in order to reinforce or redirect cell fate in vitro, it is transcription factors that are most frequently induced, over-expressed or activated. Many reviews have focused on the molecular development and genetics of gametogenesis, in vivo and in vitro, in model organisms and in humans, including several recent comprehensive reviews: here, we focus specifically on the role of transcription factors. Recent advances in stem cell biology and multi-omic studies have enabled deeper investigation into the unique transcriptional mechanisms of human reproductive development. Moreover, as methods continually improve, in vitro differentiation of germ cells can provide the platform for robust gain- and loss-of-function genetic analyses. These analyses are delineating unique and shared human germ cell transcriptional network components that, together with somatic lineage specifiers and pluripotency transcription factors, function in transitions from pluripotent stem cells to gametes. This grand theme review offers additional insight into human infertility and reproductive disorders that are linked predominantly to defects in the transcription factor networks and thus may potentially contribute to the development of novel treatments for infertility.

The core four - A panel of immunohistochemistry markers to diagnose and subtype testicular germ cell tumors

Context:

Immunohistochemistry (IHC) to differentiate germ cell tumors.

Aims:

The aim of the study is to differentiate seminomatous and nonseminomatous germ cell tumors (GCTs) with morphological overlap using a minimal and affordable panel of IHC markers.

Settings and Design:

This is a retrospective observational study.

Subjects and Methods:

All testicular GCTs (TGCT) which were diagnosed on biopsies and/or resection specimens (prechemotherapy) between January 2014 and June 2019. The demographic, clinical, and imaging findings were noted from the medical records. Hematoxylin and eosin (H and E)-stained sections were reviewed for morphology. The IHC markers constituted Octamer-binding transcription factor (OCT) 3/4, glypican 3 (GPC3), CD117, CD30, placental-like alkaline phosphatase, Sal-like protein 4, and β-human chorionic gonadotropin (HCG). IHC markers were performed in various combinations depending on the morphology, and a panel constituting OCT 3/4, CD117, GPC3, and CD30 was performed on cases with diagnostic dilemma and morphological overlaps.

Statistical Analysis Used:

Sensitivity, specificity, positive (PPV), and negative predictive value (NPV) were calculated for suggested panel of IHC OCT 3/4, CD117, GPC3, and CD30.

Results:

The study included 36 patients with TGCT with a mean age of 27 (15–58) years. Nonseminomatous tumors were the most common (86%). The concise panel was performed in 20/36 (56%) tumors to resolve the diagnosis. The sensitivity, specificity, PPV, and NPV for OCT3/4 were 80%, 55%, 31%, and 92% in seminomas and 65%, 100%, 100%, and 46% in embryonal carcinomas (EC), for CD117 was 89%, 82%, 73%, and 93% in seminomas and 60%, 77%, 60%, and 77% in yolk sac tumors (YST), for GPC3 was 95%, 90%, 95%, and 90% in YST, CD30 96%, 100%, 100%, and 91% in ECs, respectively.

Conclusions:

Designing a novel concise and affordable IHC panel constituting OCT 3/4, CD117, GPC3, and CD30 has good sensitivity and specificity in differentiating seminomas, YST, and EC, respectively. Additional markers, namely β-HCG, can be used in identifying the choriocarcinoma component.

NUTM1-Rearranged Neoplasms-A Heterogeneous Group of Primitive Tumors with Expanding Spectrum of Histology and Molecular Alterations-An Updated Review

Nuclear protein of testis (NUT), a protein product of the NUTM1 gene (located on the long arm of chromosome 15) with highly restricted physiologic expression in post-meiotic spermatids, is the oncogenic driver of a group of emerging neoplasms when fused with genes involved in transcription regulation. Although initially identified in a group of lethal midline carcinomas in which NUT forms fusion proteins with bromodomain proteins, NUTM1-rearrangement has since been identified in tumors at non-midline locations, with non-bromodomain partners and with varied morphology. The histologic features of these tumors have also expanded to include sarcoma, skin adnexal tumors, and hematologic malignancies that harbor various fusion partners and are associated with markedly different clinical courses varying from benign to malignant. Most of these tumors have nondescript primitive morphology and therefore should be routinely considered in any undifferentiated neoplasm. The diagnosis is facilitated by the immunohistochemical use of the monoclonal C52 antibody, fluorescence in situ hybridization (FISH), and, recently, RNA-sequencing. The pathogenesis is believed to be altered expression of oncogenes or tumor suppressor genes by NUT-mediated genome-wide histone modification. NUTM1-rearranged neoplasms respond poorly to classical chemotherapy and radiation therapy. Targeted therapies such as bromodomain and extraterminal domain inhibitor (BETi) therapy are being developed. This current review provides an update on NUTM1-rearranged neoplasms, focusing on the correlation between basic sciences and clinical aspects.

To Be or Not to Be a Germ Cell: The Extragonadal Germ Cell Tumor Paradigm

In the human embryo, the genetic program that orchestrates germ cell specification involves the activation of epigenetic and transcriptional mechanisms that make the germline a unique cell population continuously poised between germness and pluripotency. Germ cell tumors, neoplasias originating from fetal or neonatal germ cells, maintain such dichotomy and can adopt either pluripotent features (embryonal carcinomas) or germness features (seminomas) with a wide range of phenotypes in between these histotypes. Here, we review the basic concepts of cell specification, migration and gonadal colonization of human primordial germ cells (hPGCs) highlighting the analogies of transcriptional/epigenetic programs between these two cell types.

Expression pattern Nanog is associated with the development of gestational trophoblastic neoplasia in Chinese women from Fujian province: a case-control study

BACKGROUND

Gestational trophoblastic disease (GTD) is a group of interrelated but distinct diseases and has a serious impact on the reproductive health of women. To analyze the expression of Nanog in GTD and to evaluate its potential to predict the development of gestational trophoblastic neoplasia (GTN).

METHODS

The study included 41 normal first-trimester placentas matched by gestational age to 53 regressed-hydatidiform-moles (rHMs), 56 malignant-HMs (mHMs) and 17 choriocarcinomas (CCAs) and evaluated the Nanog expression by immunohistochemistry. The chi-square test, ANOVA, Fisher's exact test and logistic regression were performed to assess the Nanog expression and clinical prognostic factors in GTD.

RESULTS

Compared to normal placenta levels, the Nanog expression was increased in GTD samples (p < .05). In HMs, Nanog expression was positively correlated with serum β-hCG levels,uterine size and theca-lutein cysts (p < .05). Compared with the low-risk metastatic group (Federation of Gynecology and Obstetrics (FIGO) score ≤ 6), the high-risk metastatic group (FIGO score >7) had higher Nanog expression (p = .030). Moreover, logistic regression analysis showed that the positive expression of Nanog had the highest risk of developing into GTN (OR = 4.764, p < .001).

CONCLUSIONS

Nanog is an independent predictor of clinical outcomes. It can also be a reliable predictor for GTN development from GTD.

Hsa-miR-3658 down-regulates OCT4 gene expression followed by suppressing SW480 cell proliferation and migration

The pluripotency factor, OCT4 gene is a stemness marker that is involved in the tumorigenicity of different cancer types and knowing about molecular mechanisms of its regulation is crucially important. To date, a few microRNAs (miRNAs) are known to be regulators of OCT4 gene expression. Looking for the novel miRNAs which are capable of regulating OCT4 gene expression, our bioinformatics analysis introduced hsa-miR-3658 (miR-3658) as a bona fide candidate. Then, RT-qPCR results indicated that miR-3658 expression is decreased in colorectal cancer (CRC) tumor tissues, compared with normal pairs. Furthermore, RT-qPCR and western blot analysis showed that the OCT4 gene has been down-regulated following the miR-3658 overexpression. Consistently, dual-luciferase assay supported the direct interaction of miR-3658 with the 3'-UTR sequence of OCT4 gene. Unlike in HCT116 cells, overexpression of miR-3658 in SW480 cells brought about growth inhibition, cell cycle arrest and reduced cell migration, detected by flow cytometry, and scratch test assay. Overall, these findings demonstrated that miR-3658 as a tumor suppressor miRNA exerts its effect against OCT4 gene expression, and it has the potential of being used as a prognostic marker and therapeutic target against colorectal cancer.

TRPA1 Expression in Synovial Sarcoma May Support Neural Origin

Synovial sarcoma (SS) is a malignant mesenchymal soft tissue neoplasm. Despite its name, the cells of origin are not synovial cells, but rather neural, myogenic, or multipotent mesenchymal stem cells have been proposed as possible cells originators. Unlike other sarcomas, an unusual presentation of long-term pain at the tumor site has been documented, but the exact mechanisms have not been fully clarified yet. The transient receptor potential ankyrin 1 (TRPA1) is a nonselective cation channel mainly expressed in primary sensory neurons, where it functions as a pain sensor. TRPA1 have also been described in multiple non-excitable cells, including those derived from neural crest stem cells such as glial cells and, in particular, Schwann cell oligodendrocytes and astrocytes. We evaluated TRPA1 expression in SS. We selected a cohort of 41 SSs, and by immunohistochemistry, we studied TRPA1 expression. TRPA1 was found in 92.6% of cases. Triple TRPA1/pS100/SOX10 and TRPA1/SLUG/SNAIL staining strongly supports a neural origin of SS. TRPA1 positivity was also observed in a subset of cases negative with pS100, SOX10 and/or SLUG/SNAIL, and these divergent phenotypes may reflect a process of tumor plasticity and dedifferentiation of neural-derived SSs. Given the functional diversity of TRPA1 and its expression in neuronal and non-neuronal multipotent neural crest stem cells, it remains to be determined whether TRPA1 expression in SSs neoplastic cells plays a role in the molecular mechanism associated with premonitory pain symptoms and tumor progression.

SALL4 is a useful marker for pediatric yolk sac tumors

BACKGROUND

SALL4 is a zinc finger transcription factor that exerts its physiological role during embryo-fetal development. Analyses of SALL4 expression have shown its oncogenic role in precursor B-cell lymphoblastic lymphoma, acute and chronic myeloid leukemia, gastrointestinal, breast, and lung cancers. The aim of this study was to determine the immunohistochemical profile of SALL4 in pediatric yolk sac tumors (YSTs).

METHODS AND RESULTS

Immunohistochemistry detection of SALL4 was performed in 22 cases of pediatric YSTs and 10 mature teratomas. The percentage of tumor cells stained was scored as 0, 1+ (1-30% cells), 2+ (31-60%), 3+ (61-90%), and 4+ (> 90%). To compare its sensitivity and specificity with Glypican-3 and α-fetoprotein (AFP), we also stained tumors from these cases for Glypican-3 and AFP. In contrast to AFP and glypican-3, SALL4 staining in more than 90% of the tumor cells was seen in all 22 pediatric YSTs (100% sensitivity) (P < 0.001 for both SALL4 vs. AFP and SALL4 vs. glypican-3).

CONCLUSIONS

SALL4 is a sensitive marker for pediatric YSTs and it can be used to distinguish them from mature teratomas. SALL4 is likely to become a new and valuable biomarker for the diagnosis of pediatric YST.

Practical Application of Lineage-Specific Immunohistochemistry Markers: Transcription Factors (Sometimes) Behaving Badly

CONTEXT.—

Transcription factors (TFs) are proteins that regulate gene expression and control RNA transcription from DNA. Lineage-specific TFs have increasingly been used by pathologists to determine tumor lineage, especially in the setting of metastatic tumors of unknown primary, among other uses. With experience gathered from its daily application and increasing pitfalls reported from immunohistochemical studies, these often-touted highly specific TFs are not as reliable as once thought.

OBJECTIVES.—

To summarize the established roles of many of the commonly used TFs in clinical practice and to discuss known and potential sources for error (eg, false-positivity from cross-reactivity, aberrant, and overlap "lineage-specific" expression) in their application and interpretation.

DATA SOURCES.—

Literature review and the authors' personal practice experience were used. Several examples selected from the University Health Network (Toronto, Ontario, Canada) are illustrated.

CONCLUSIONS.—

The application of TF diagnostic immunohistochemistry has enabled pathologists to better assess the lineage/origin of primary and metastatic tumors. However, the awareness of potential pitfalls is essential to avoid misdiagnosis.

Impact of Teratoma on the Cumulative Incidence of Disease-Related Death in Patients With Advanced Germ Cell Tumors

PURPOSE

In men with metastatic germ cell tumors (GCTs), risk-directed treatment is determined, in part, by a distinction between seminoma and nonseminomatous GCT (NSGCT). The importance of NSGCT cell type is uncertain. We evaluated the long-term impact of teratoma on survival in patients with NSGCT.

METHODS

Prechemotherapy, primary tumors from patients who received platinum-based chemotherapy were studied, and the histology was confirmed by a genitourinary pathologist. The cumulative incidence of disease-related death (CIDD) was the primary end point, and a competing-risk analysis was performed.

RESULTS

Tumors were available from 232 patients, including 193 with NSGCT. An element of teratoma was present in 82 NSGCT primary tumors (42%). With a median follow-up of 17 years (range, 0.3 to 35 years), 58 patients with NSGCT died, 47 as a result of GCT and 11 as a result of other causes. Most GCT deaths occurred within the first 5 years and were associated with pretreatment risk status (P < .001). Death as a result of other causes rose steadily after 15 years and was not associated with risk status (P = .66). A higher CIDD was observed in patients who had NSGCT with teratoma than those with NSGCT without teratoma and seminoma (5-year CIDD rate, 27.4%, 17.4%, and 10.3%, respectively; P = .03). A higher CIDD was observed in patients who had NSGCT with mature teratoma compared with those with either NSGCT with immature teratoma or NSGCT without teratoma (5-year CIDD rate, 38.1%, 19.9%, and 17.4%, respectively; P = .01).

CONCLUSION

The presence of teratoma, particularly mature teratoma, in an NSGCT primary tumor is associated with a higher CIDD, consistent with the hypothesis that differentiation is associated with adverse outcomes. Death as a result of non-GCT causes is not associated with risk status and must be separated from GCT death when evaluating long-term survival.

Effect of overexpression of Oct4 and Sox2 genes on the biological and oncological characteristics of gastric cancer cells

Objective: Using the gastric cancer cell line SGC7901, we constructed a cell line that overexpressed octamer-binding protein 4 (Oct4) and SRY-box 2 (Sox2) to explore the stem cell oncological and biological characteristics of these cells and to elucidate the mechanisms of Oct4 and Sox2 in cancer.

Methods: A lentiviral vector containing the Sox2 gene was constructed and transfected into a gastric cancer cell line overexpressing Oct4 (SGC7901-Oct4) to obtain a stably transfected cell line (SGC7901-Oct4-Sox2). Oct4 and Sox2 expression was detected by RT-PCR and Western blotting. The proliferation, drug resistance, migration, and invasion abilities of the cells were assessed using in vitro (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium), drug resistance, scratch-wound migration, transwell migration, transwell invasion, and spherical clone formation assays, and their tumorigenic ability was assessed using a tumor formation experiment in mice.

Results: Compared with the control group, the expression of Oct4, Sox2, CD44, and E-cadherin was significantly higher in the group that overexpressed Oct4 and Sox2, while the expression of c-Myc and Klf4 did not significantly change. The proliferation, drug resistance, migration, and invasion abilities were significantly enhanced in the overexpression group, and the tumorigenic ability in mice was also significantly enhanced, with significantly increased tumor size and weight.

Conclusion: The proliferation, drug resistance, migration, invasion, and tumorigenic abilities of SGC7901 cells overexpressing Oct4 and Sox2 were significantly improved. Oct4 and Sox2 play important roles in the proliferation, migration, invasion, and tumorigenicity of gastric cancer cells, and the two genes may be synergistic to a certain degree.

High expression of Oct4 and Nanog predict poor prognosis in intrahepatic cholangiocarcinoma patients after curative resection

Oct4 and Nanog are reported to promote tumor progression in several cancers, but the effect on intrahepatic cholangiocarcinoma (ICC) is unknown. The aim of our present study was to explore the prognostic role of Oct4 and Nanog on patients with ICC. Immunohistochemistry was used to detect the expression of Oct4 and Nanog in a random cohort of 116 ICC patients, and validated in another independent cohort of 103 patients. Prognostic nomograms were formulated for OS and RFS prediction of ICC patients. Our results showed Oct4 and Nanog highly expressed in ICC tumor tissues and were identified as independent prognostic factors for patients' OS and RFS. Significant positive correlation was found between Oct4 and Nanog expression. Co-expression of Oct4 and Nanog implied the poorest OS and RFS in ICC patients. Our nomograms comprising Oct4 and Nanog achieved better predictive accuracy in training and validation cohorts compared with AJCC 7th edition and LCSGJ stage for OS and RFS prediction. Our study support the high expression of Oct4 and Nanog in ICC implies aggressive tumor behaviors and suggest a poor clinical prognosis, which emerges as valuable biomarkers for identifying patients at high risk after curative resection.

BORIS: a key regulator of cancer stemness

BORIS (CTCFL) is a DNA binding protein which is involved in tumorigenesis. Although, there are different opinions on the level of gene expression and function of BORIS in normal and cancer tissues, the results of many studies have classified BORIS as a protein belonging to cancer/testis (CT) genes, which are identified as a group of genes that are expressed normally in testis, and abnormally in various types of cancers. In testis, BORIS induces the expression of some male germ cell/testis specific genes, and plays crucial roles during spermatogenesis and production of sperm. In tumorigenesis, the role of BORIS in the expression induction of some CT genes and oncogenes, as well as increasing proliferation/viability of cancer cells has been demonstrated in many researches. In addition to cancer cells, some believe that BORIS is also expressed in normal conditions and plays a universal function in cell division and regulation of genes. The following is a comprehensive review on contradictory views on the expression pattern and biological function of BORIS in normal, as well as cancer cells/tissues, and presents some evidence that support the expression of BORIS in cancer stem cells (CSCs) and advanced stage/poorer differentiation grade of cancers. Boris is involved in the regulation of CSC cellular and molecular features such as self-renewal, chemo-resistance, tumorigenicity, sphere-forming ability, and migration capacity. Finally, the role of BORIS in regulating two important signaling pathways including Wnt/β-catenin and Notch in CSCs, and its ability in recruiting transcription factors or chromatin-remodeling proteins to induce tumorigenesis is discussed.

Proliferation genes in lung development associated with the prognosis of lung adenocarcinoma but not squamous cell carcinoma

There are many similarities between embryonic development and tumorigenesis, and gene expression profiles show that certain correlations exist between the gene signature during development and the clinical phenotypes of different cancers. Our group previously reported the gene expression profiles of human lung development, and the expression of one group of proliferation-related genes (PTN1 genes) steadily decreased during lung development. Here, we examined the prognostic value of PTN1 genes in 5 independent lung adenocarcinoma (ADC) and 5 lung independent squamous cell carcinoma (SCC) microarray datasets and found that the expression levels of PTN1 genes were associated with survival in lung ADC but not lung SCC. All of the lung ADC datasets contained a set of highly correlated genes from PTN1 genes, but the lung SCC datasets had no similar set of genes. We identified 63 unique core genes from the PTN1 genes in the 5 lung ADC datasets: 17 of these core genes appeared in at least 4 of the lung ADC datasets, and the 17 corresponding proteins clearly interacted more strongly with each other in lung ADC than in lung SCC. Moreover, 16 of the 17 core genes play major roles in the G₂ /M phase of the cell cycle. These data indicate that proliferation-related genes in lung development have a significant prognostic value for lung ADC; the synergistic effects of the 17 core genes play an important role in lung ADC prognosis. These genes may have significant clinical implications for the treatment and prognosis of lung ADC.

Gastric Cancer With Primitive Enterocyte Phenotype: An Aggressive Subgroup of Intestinal-type Adenocarcinoma

A primitive cell-like gene expression signature is associated with aggressive phenotypes of various cancers. We assessed the expression of phenotypic markers characterizing primitive cells and its correlation with clinicopathologic and molecular characteristics in gastric cancer. Immunohistochemical analysis of a panel of primitive phenotypic markers, including embryonic stem cell markers (OCT4, NANOG, SALL4, CLDN6, and LIN28) and known oncofetal proteins (AFP and GPC3), was performed using tissue microarray on 386 gastric cancers. On the basis of the expression profiles, the 386 tumors were clustered into 3 groups: group 1 (primitive phenotype, n=93): AFP, CLDN6, GPC3, or diffuse SALL4 positive; group 2 (SALL4-focal, n=56): only focal SALL4 positive; and group 3 (negative, n=237): all markers negative. Groups 1 and 2 predominantly consisted of intestinal-type adenocarcinoma, including 13 fetal gut-like adenocarcinomas exclusively in group 1. Group 1 was significantly associated with higher T-stage, presence of vascular invasion and nodal metastasis when compared with groups 2 and 3. Group 1 was associated with patients' poor prognosis and was an independent risk factor for disease-free survival. Group 1 showed frequent TP53 overexpression and little association with Epstein-Barr virus or mismatch repair deficiency. Further analysis of the Cancer Genome Atlas data set validated our observations and revealed that tumors with primitive phenotypes were mostly classified as "chromosomal instability" in the Cancer Genome Atlas' molecular classification. We identified gastric cancer with primitive enterocyte phenotypes as an aggressive subgroup of intestinal-type/chromosomal instability gastric cancer. Therapeutic strategies targeting primitive markers, such as GPC3, CLDN6, and SALL4, are highly promising.

Application of Immunohistochemistry in Undifferentiated Neoplasms: A Practical Approach

Context.—

Advances in interventional technology have enhanced the ability to safely sample deep-seated suspicious lesions by fine-needle aspiration procedures. These procedures often yield scant amounts of diagnostic material, yet there is an increasing demand for the performance of more ancillary tests, especially immunohistochemistry and, not infrequently, molecular assays, to increase diagnostic sensitivity and specificity. A systematic approach to conserving diagnostic material is the key, and our previously proposed algorithm can be applied aptly in this context.

Objective.—

To elaborate a simple stepwise approach to the evaluation of cytology fine-needle aspiration specimens and small biopsy tissue specimens, illustrating the algorithmic application of small panels of immunohistochemical stains in providing an accurate diagnosis with scant amounts of tissue, including the potential pitfalls that may arise while using immunohistochemical staining on small quantities of tissue.

Data Sources.—

The sources include literature (PubMed), the first Chinese American Pathologists Association Diagnostic Pathology Course material, and the review authors' research data as well as practice experience. Seven examples selected from the CoPath database at Geisinger Medical Center (Danville, Pennsylvania) are illustrated.

Conclusions.—

A stepwise approach to the evaluation of fine-needle aspiration and small biopsy tissue specimens in conjunction with a small panel of select immunohistochemical stains has been successful in accurately assessing the lineage/origin of the metastatic tumors of unknown primaries. The awareness of the common pitfalls of these biomarkers is essential in many instances.

DHFR and MDR1 upregulation is associated with chemoresistance in osteosarcoma stem-like cells

Tumor-initiating cells (TICs) are defined as a specialized subset of cells with tumor-initiating capacity that can initiate tumor growth, tumor relapse and metastasis. In the present study, osteosarcoma TICs (OS-TICs) were isolated and enriched from the osteosarcoma U2OS and MG-63 cell lines using sphere formation assays and serum-depleted media. These enriched OS-TICs showed the expression of several typical cancer stemness markers, including octamer-binding transcription factor 4, Nanog homeobox, cluster of differentiation (CD)117, Nestin and CD133, and the expression of ATP binding cassette subfamily G member 2, multidrug resistance protein 1 (MDR1) and dihydrofolate reductase (DHFR). Notably, in vitro and in vivo tumorigenic properties were enhanced in these OS-TICs. Additionally, methotrexate and doxorubicin are the most widely used anticancer agents against osteosarcoma, and the observed enhanced chemoresistance of OS-TICs to these two agents could be associated with the upregulation of DHFR and MDR1. These findings suggest that the upregulation of DHFR and MDR1 is associated with the development of chemoresistance of OS-TICs.

Knockdown of stem cell regulator Oct4A in ovarian cancer reveals cellular reprogramming associated with key regulators of cytoskeleton-extracellular matrix remodelling

Oct4A is a master regulator of self-renewal and pluripotency in embryonic stem cells. It is a well-established marker for cancer stem cell (CSC) in malignancies. Recently, using a loss of function studies, we have demonstrated key roles for Oct4A in tumor cell survival, metastasis and chemoresistance in in vitro and in vivo models of ovarian cancer. In an effort to understand the regulatory role of Oct4A in tumor biology, we employed the use of an ovarian cancer shRNA Oct4A knockdown cell line (HEY Oct4A KD) and a global mass spectrometry (MS)-based proteomic analysis to investigate novel biological targets of Oct4A in HEY samples (cell lysates, secretomes and mouse tumor xenografts). Based on significant differential expression, pathway and protein network analyses, and comprehensive literature search we identified key proteins involved with biologically relevant functions of Oct4A in tumor biology. Across all preparations of HEY Oct4A KD samples significant alterations in protein networks associated with cytoskeleton, extracellular matrix (ECM), proliferation, adhesion, metabolism, epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs) and drug resistance was observed. This comprehensive proteomics study for the first time presents the Oct4A associated proteome and expands our understanding on the biological role of this stem cell regulator in carcinomas.

Growth and Differentiation Factor 3 Is Transcriptionally Regulated by OCT4 in Human Embryonic Carcinoma Cells

Growth and differentiation factor 3 (GDF3), a mammalian-specific transforming growth factor β ligand, and OCT4, one of key stem cell transcription factors, are expressed in testicular germ cell tumors (TGCTs) as well as pluripotent stem cells. To understand the molecular mechanism by which OCT4 and GDF3 function in tumorigenesis as well as stemness, we investigated the transcriptional regulation of GDF3 mediated by OCT4 in human embryonic carcinoma (EC) NCCIT cells, which are pluripotent stem cells of TGCTs. GDF3 and OCT4 was highly expressed in undifferentiated NCCIT cells and then significantly decreased upon retinoic acid-induced differentiation in a time-dependent manner. Moreover, GDF3 expression was reduced by short hairpin RNA-mediated knockdown of OCT4 and increased by OCT4 overexpression, suggesting that GDF3 and OCT4 have a functional relationship in pluripotent stem cells. A promoter-reporter assay revealed that the GDF3 promoter (-1721-Luc) activity was significantly activated by OCT4 in a dose-dependent manner. Moreover, the minimal promoter (-183-Luc) was sufficient for OCT4-mediated transcriptional activation and provided a potential binding site for the direct interaction with OCT4. Collectively, this study provides the evidence about the regulatory mechanism of GDF3 mediated by OCT4 in pluripotent EC cells.

Calmidazolium chloride inhibits growth of murine embryonal carcinoma cells, a model of cancer stem-like cells

Calmidazolium chloride (CMZ) is widely used as a calmodulin (CaM) antagonist, but is also known to induce apoptosis in certain cancer cell lines. However, in spite of the importance of cancer stem cells (CSCs) in cancer therapy, the effects of CMZ on CSCs are not yet well understood. We investigated the effects of CMZ on the F9 embryonal carcinoma cell (ECC) line as a surrogate model of CSCs. To avoid bias due to culture conditions, F9 ECCs and E14 embryonic stem cells (ESCs) were grown in the same culture medium. Results obtained using a cell-counting kit showed that CMZ significantly inhibited growth in F9 ECCs compared with growth in E14 ESCs. CMZ also induced apoptosis of F9 ECCs, but not of E14 ESCs, which was associated with caspase-3 activation and an increased fraction of the sub-G1 cell population. In addition, our data revealed that the expression of stemness-related genes including c-Myc was selectively down regulated in CMZ-treated F9 ECCs. Our results suggest that CMZ can inhibit the growth of ECCs by inducing apoptosis and down regulating stemness-related genes, without causing any harm to normal stem cells. These findings indicate a potential application of CMZ in the development of anti-CSC therapeutics.

Chromatin immunoprecipitation from fixed clinical tissues reveals tumor-specific enhancer profiles

Extensive cross-linking introduced during routine tissue fixation of clinical pathology specimens severely hampers chromatin immunoprecipitation followed by next-generation sequencing (ChIP-seq) analysis from archived tissue samples. This limits the ability to study the epigenomes of valuable, clinically annotated tissue resources. Here we describe fixed-tissue chromatin immunoprecipitation sequencing (FiT-seq), a method that enables reliable extraction of soluble chromatin from formalin-fixed paraffin-embedded (FFPE) tissue samples for accurate detection of histone marks. We demonstrate that FiT-seq data from FFPE specimens are concordant with ChIP-seq data from fresh-frozen samples of the same tumors. By using multiple histone marks, we generate chromatin-state maps and identify cis-regulatory elements in clinical samples from various tumor types that can readily allow us to distinguish between cancers by the tissue of origin. Tumor-specific enhancers and superenhancers that are elucidated by FiT-seq analysis correlate with known oncogenic drivers in different tissues and can assist in the understanding of how chromatin states affect gene regulation.

Expression of OCT-4 and SOX-2 in Bone Marrow-Derived Human Mesenchymal Stem Cells during Osteogenic Differentiation

AIM:

Determine the levels of expression of pluripotency genes OCT-4 and SOX-2 before and after osteogenic differentiation of human mesenchymal stem cells (hMSCs).

METHODS:

Human MSCs were derived from the bone marrow and differentiated into osteoblasts. The analyses were performed on days 0 and 14 of the cell culture. In vitro differentiation was evaluated due to bone markers – alkaline phosphatase (AP) activity and the messenger RNA (mRNA) expression of AP and bone sialoprotein (BSP). The OCT-4 and SOX-2 expression was evaluated at mRNA level by real-time qPCR and at protein level by immunocytochemistry.

RESULTS:

In vitro cultures on day 14 showed an increase in AP activity and upregulation of AP and BSP gene expression. OCT-4 and SOX-2 in undifferentiated hMSCs on day 0 is detectable and very low compared to tumor cell lines as a positive control. Immunocytochemistry detected OCT-4 in the cell nuclei prior (day 0) and post differentiation (day 14). On the same time points, cultures were negative for SOX-2 protein.

CONCLUSION:

Messenger RNA for pluripotency markers OCT-4 and SOX-2 isolated from hMSCs was less present, while OCT-4 protein was detected in cell nuclei prior and post differentiation into osteoblast lineage.

A basal stem cell signature identifies aggressive prostate cancer phenotypes

Evidence from numerous cancers suggests that increased aggressiveness is accompanied by up-regulation of signaling pathways and acquisition of properties common to stem cells. It is unclear if different subtypes of late-stage cancer vary in stemness properties and whether or not these subtypes are transcriptionally similar to normal tissue stem cells. We report a gene signature specific for human prostate basal cells that is differentially enriched in various phenotypes of late-stage metastatic prostate cancer. We FACS-purified and transcriptionally profiled basal and luminal epithelial populations from the benign and cancerous regions of primary human prostates. High-throughput RNA sequencing showed the basal population to be defined by genes associated with stem cell signaling programs and invasiveness. Application of a 91-gene basal signature to gene expression datasets from patients with organ-confined or hormone-refractory metastatic prostate cancer revealed that metastatic small cell neuroendocrine carcinoma was molecularly more stem-like than either metastatic adenocarcinoma or organ-confined adenocarcinoma. Bioinformatic analysis of the basal cell and two human small cell gene signatures identified a set of E2F target genes common between prostate small cell neuroendocrine carcinoma and primary prostate basal cells. Taken together, our data suggest that aggressive prostate cancer shares a conserved transcriptional program with normal adult prostate basal stem cells.

SOX2 Expression in Gastrointestinal Cancers of Iranian Patients

Purpose

Gastrointestinal (GI) malignancies are among the 5 most common cancers in Iran, and their high associated mortality rates are attributable to late diagnosis and poor treatment options. SOX2, a transcription factor necessary for maintenance and induction of pluripotency and self-renewal, has been identified as a lineage-survival oncogene in several cancers. In the present study, we examined SOX2 expression in esophageal squamous cell carcinoma (ESCC), gastric adenocarcinoma and colon squamous cell carcinoma (SCC), as well as normal GI tissues, in Iranian patients.

Methods

To elucidate the role of SOX2 in GI carcinogenesis, formalin-fixed tissues were analyzed using immunohistochemistry (IHC), while frozen ESCC samples were studied by quantitative reverse transcription polymerase chain reaction (qRT-PCR).

Results

IHC studies indicated presence of SOX2+ cells in a subset of cancerous and normal tissues of stomach and colon, while no significant difference was observed between groups, and no correlation was found between SOX2 expression and tumors grades. Nevertheless, studying ESCC samples with IHC and qRT-PCR revealed overexpression of SOX2 in comparison with normal adjacent tissues.

Conclusions

The present results are in line with other studies and indicate SOX2 up-regulation in ESCC; however, due to our small sample size and contradictory reports, more research is needed to determine the importance of SOX2 in GI cancers.

Germ cell tumors: looking to the future

Our knowledge about the management of men with germ cell tumors (GCTs) and its tumor biology continues to evolve. Vascular disease, metabolic syndrome, second malignant neoplasms, and hypogonadism occur after treatment for GCTs and the latency pattern resembles that seen in patients treated for Hodgkin lymphoma. Patients receiving treatment for GCTs should be informed not only of the near-term toxicity (experienced during or shortly after administration), but also the delayed and late effects of chemotherapy and the need for lifelong surveillance for all late outcomes, including late relapse. Recent data suggest that the treatment outcome of patients with intermediate-risk, poor-risk, and relapsed GCTs can be improved through multicenter trials that include the general oncology community. Finally, GCTs are a malignancy of primordial germ cells. Programmed differentiation is clinically evident in vivo and probably related to chemotherapy resistance. This biology has much clinical relevance, some of which is already in use.

The Utility of Immunohistochemistry in the Differential Diagnosis of Gynecologic Disorders

Context

Immunohistochemistry has assumed an increasing role in the identification and characterization of gynecologic disorders including lesions with deceptively bland morphology, uncommon and underdiagnosed neoplasms, and neoplasms with specific genetic alterations associated with overexpression or loss of expression of specific proteins. The diagnostic accuracy has been significantly improved owing to the discovery and increasing experience with the tumor-associated biomarkers, and the increasing demand for precise tumor classification to assess suitability for the expanding therapeutic modalities including clinical trials.

Objective

To differentiate lesions of the gynecologic tract through the use of effective immunohistochemical panels.

Data Sources

Literature review and authors' personal practice experience.

Conclusions

The application of diagnostic and prognostic immunohistochemical panels has enabled pathologists to better guide therapeutic decisions and to better predict the clinical outcome. It is now well established that the use of ancillary testing, including immunohistochemistry, has a significant power in the identification, differentiation, and classification of reactive, premalignant, and malignant gynecologic disorders. This article discusses the utilities and pitfalls of the commonly used immunohistochemical markers in the context of overlapping morphologic features encountered in the uterus, ovaries, and fallopian tubes.

Isolation of colorectal cancer stem-like cells

This study is aimed at isolating colorectal cancer stem-like cells in vitro using a neurosphere assay method employed in isolating gliobastoma multiforme tumor cells. This was followed with confirmation of the isolated cells by flow cytometry, pluripotent genes expression and in vivo tumorigenicity assay. Using this culture assay, stem-like and non-stem-like CRC cells were isolated and expanded in vitro from purchased Balb/c mice induced with CT26 colorectal cancer (CRC) cell line. The procedure includes an initial mechanical dissociation and chemical digestion of tumor tissue and subsequently plating the resulting single cell suspension in serum-free medium (SFM) or serum-containing medium (SCM). This selectively permits growth of cancer stem-like cells in SFM and eliminates non-stem-like cancer cells through the process of anoikis or apoptosis. CRC stem cells derived cultures proliferated as non-adherent spheres in vitro in different shapes and sizes. These cells expressed cell surface markers previously reported for tumor stem cells, including CD44, CD133, CD166 and CD26 and formed tumors when implanted in severe combined immunodeficient mice in a concentration dependent manner. Importantly, the stem-like cells had self-renewal properties with significantly higher expression of the pluripotent stem cell genes NANOG, OCT4, and SOX2 compared to the adherent non-stem cells. Collectively, the results of this study indicate that SFM is a defined culture medium that enriches for CRC stem-like cells and represents a suitable in vitro model for the study of CRC stem-like cells. This finding may be useful in developing therapeutic strategies aimed at eradicating the tumorigenic subpopulation within colorectal cancer.

Myoepithelial tumor of soft tissue: histology and genetics of an evolving entity

Myoepithelial neoplasms represent a heterogeneous group of tumors of which classification is incomplete and evolving. Those of the soft tissues often form genetically distinct subgroups that differ from those arising within salivary glands. Soft-tissue myoepithelial tumors (including mixed tumors that show true glandular or ductal differentiation) exhibit a spectrum of different morphologic patterns, making them difficult to distinguish from a variety of other neoplasms. They have been increasingly shown to harbor genetic fusions involving EWSR1 and partner genes that are not seen in the well-characterized tumor classes involving EWSR1 translocations. We review the spectrum of soft-tissue myoepithelial tumors, discussing recent immunohistochemical and genetic findings and the differential diagnosis.

Significant association of combination of OCT4, NANOG, and SOX2 gene polymorphisms in susceptibility and response to treatment in North Indian breast cancer patients

PURPOSE

Dysregulations of regulatory genes in embryonic stem cells (ESCs) gene polymorphisms may lead to breast cancer cell growth, differentiation, and tumor metastasis.

METHODS

Polymorphisms in OCT4 (rs3130932), NANOG (rs11055786), LIN28 (rs4274112), and SOX2 (rs11915160) genes were evaluated for susceptibility in 297 breast cancer females and 273 healthy controls from north Indian population. Response to neo-adjuvant chemotherapy was followed in 128 locally advanced breast cancer patients along with clinicopathological features. Genotyping was done using TaqMan allelic discrimination assays. Statistical analysis was performed using SPSS and multifactor dimensionality reduction (MDR).

RESULTS

For OCT4 gene polymorphism, protective effect of genotypes AC [P corr = 0.031, OR = 0.63 (0.44-0.91)] and AC+CC [P corr = 0.031, OR = 0.68 (0.48-0.95)] was seen in patients. However, no association of NANOG, LIN28, and SOX2 gene polymorphisms was found with overall breast cancer susceptibility. Further, significant association of AG+GG genotype [P corr = 0.021, OR = 6.08 (1.83-20.15)] and G allele [P corr = 0.021, OR = 3.07 (1.21-7.77)] of rs4274112 polymorphism was seen with positive lymph node. For OCT4, significant association of allele C was seen with patients having negative hormone receptor [P corr = 0.021, OR = 0.51 (0.29-0.90)], but no association of any of the studied polymorphisms individually was found with response to NACT. On MDR analysis, we found combination of SNPs SOX2 rs11915160, OCT4 rs3130932, and NANOG rs11055786 to be the best interaction model for predicting breast cancer risk [p for permutation test <10(-3), OR = 2.04 (1.43-2.910] and response to NACT [p for permutation test = 0.005, OR = 2.09 (1.24-3.52)].

CONCLUSION

Combination of genetic variants of ESCs gene may have a profound effect in breast cancer risk and response to NACT.

Best practices recommendations in the application of immunohistochemistry in testicular tumors: report from the International Society of Urological Pathology consensus conference

The judicious use of immunostains can be of significant diagnostic assistance in the interpretation of testicular neoplasms when the light microscopic features are ambiguous. A limited differential diagnosis by traditional morphology is required for the effective use of immunohistochemistry (IHC); otherwise, the inevitable occurrence of exceptions to anticipated patterns will lead to "immunoconfusion." The diagnosis of tumors in the germ cell lineage, the great majority of primary tumors of the testis, has been considerably facilitated over the past decade by IHC directed at developmentally important nuclear transcription factors, including OCT4, SALL4, SOX2, and SOX17, that are mostly restricted to certain tumor histotypes. In conjunction with other markers, a specific diagnosis can be achieved in most instances through a panel of 3 or 4 immunostains and often fewer. IHC among tumors in the sex cord-stromal group may produce a significant proportion of false-negative cases until more sensitive and equally specific markers are validated. The negativity of these tumors for the IHC stains used for germ cell tumors is key in the important distinction of neoplasms in these 2 general categories. In this review, the International Society of Urological Pathologists (ISUP) provides diagnostic guidelines in the form of algorithms to assist practicing pathologists confronting a differential diagnostic question concerning a testicular neoplasm. The goal of ISUP is to anticipate commonly encountered differential diagnoses and recommend an efficient and limited pattern of IHC stains to resolve the question.

Expression analysis of BORIS during pluripotent, differentiated, cancerous, and non-cancerous cell states

BORIS/CTCFL is an 11 zinc finger protein, which is the paralog of CTCF, a ubiquitously expressed protein with diverse roles in gene expression and chromatin organization. Several studies have shown that the expression of BORIS is restricted to normal adult testis, pluripotent cells, and diverse cancer cell lines. Thus, it is known as a cancer-testis (CT) gene that has been hypothesized to exhibit oncogenic properties and to be involved in cancer cell proliferation. On the contrary, other reports have shown that its expression is more widespread and can be detected in differentiated and normal somatic cells; hence, it might have roles in general cellular functions. The present study was aimed to analyze the expression of BORIS in different cell states of pluripotent, differentiated, cancerous and non-cancerous.We found that the two cell states of pluripotency and differentiation are not accompanied with significant variations of BORIS expression. Furthermore, Boris transcripts were detected at approximately the same level in cancer and non-cancer cell lines. These findings suggest that, in contrast to some previous reports, the expression of mouse BORIS is not limited to only cancerous cells or pluripotent cell states.

An oncofetal and developmental perspective on testicular germ cell cancer

Germ cell tumors (GCTs) represent a diverse group of tumors presumably originating from (early fetal) developing germ cells. Most frequent are the testicular germ cell cancers (TGCC). Overall, TGCC is the most frequent malignancy in Caucasian males (20-40 years) and remains an important cause of (treatment related) mortality in these young men. The strong association between the phenotype of TGCC stem cell components and their totipotent ancestor (fetal primordial germ cell or gonocyte) makes these tumors highly relevant from an onco-fetal point of view. This review subsequently discusses the evidence for the early embryonic origin of TGCCs, followed by an overview of the crucial association between TGCC pathogenesis, genetics, environmental exposure and the (fetal) testicular micro-environment (genvironment). This culminates in an evaluation of three genvironmentally modulated hallmarks of TGCC directly related to the oncofetal pathogenesis of TGCC: (1) maintenance of pluripotency, (2) cell cycle control/cisplatin sensitivity and (3) regulation of proliferation/migration/apoptosis by KIT-KITL mediated receptor tyrosine kinase signaling. Briefly, TGCC exhibit identifiable stem cell components (seminoma and embryonal carcinoma) and progenitors that show large and consistent similarities to primordial/embryonic germ cells, their presumed totipotent cells of origin. TGCC pathogenesis depends crucially on a complex interaction of genetic and (micro-)environmental, i.e. genvironmental risk factors that have only been partly elucidated despite significant effort. TGCC stem cell components also show a high degree of similarity with embryonic stem/germ cells (ES) in the regulation of pluripotency and cell cycle control, directly related to their exquisite sensitivity to DNA damaging agents (e.g. cisplatin). Of note, (ES specific) micro-RNAs play a pivotal role in the crossover between cell cycle control, pluripotency and chemosensitivity. Moreover, multiple consistent observations reported TGCC to be associated with KIT-KITL mediated receptor tyrosine kinase signaling, a pathway crucially implicated in proliferation, migration and survival during embryogenesis including germ cell development. In conclusion, TGCCs are a fascinating model for onco-fetal developmental processes especially with regard to studying cell cycle control, pluripotency maintenance and KIT-KITL signaling. The knowledge presented here contributes to better understanding of the molecular characteristics of TGCC pathogenesis, translating to identification of at risk individuals and enhanced quality of care for TGCC patients (diagnosis, treatment and follow-up).

Oncogenic signaling pathways and origins of tumor-initiating stem-like cells of hepatocellular carcinomas induced by hepatitis C virus, alcohol and/or obesity

This review article discusses the importance and oncogenic signaling pathways of tumor-initiating cells (TICs) in several etiologies of hepatocellular carcinomas (HCCs) induced by hepatitis C virus (HCV), alcohol, obesity and/or chemicals. Stem cells may be present in cancer tissue, and a hierarchy of cells is formed, as is the case for normal tissue. Tumor formation, growth and propagation are maintained by a small proportion of cells with stem cell-like properties. TICs are present in alcohol-fed HCV transgenic mice, diethylnitrosamine/phenobarbital-treated mice (chemical carcinogenesis) and Spnb2 +/- mice (defective TGF-β signal). Alcohol/obesity-associated endotoxemia induces the stem cell marker Nanog through TLR4 signaling to generate TICs and liver tumors in several HCC models. The oncogenic pathway (such as the STAT3 and TLR4-NANOG pathway) and mechanism of generation of TICs of HCCs associated with HCV, alcohol and obesity are discussed. Understanding the molecular stemness signaling and cellular hierarchy and defining key TIC-specific genes will accelerate the development of novel biomarkers and treatment strategies. This review highlights recent advances in understanding the pathogenesis of liver TICs and discusses unanswered questions about the concept of liver TICs. (This project was supported by NIH grants 1R01AA018857 and P50AA11999).

Transcriptional activation of OCT4 by the ETS transcription factor PEA3 in NCCIT human embryonic carcinoma cells

We examined the molecular mechanism of OCT4 gene regulation by polyomavirus enhancer activator 3 (PEA3) in NCCIT cells. Endogenous PEA3 and OCT4 were significantly elevated in undifferentiated cells and reduced upon differentiation. PEA3 knockdown led to a reduction in OCT4 levels. OCT4 promoter activity was significantly up-regulated by dose-dependent PEA3 overexpression. Deletion and site-directed mutagenesis of the OCT4 promoter revealed a putative binding site within the conserved region 2 (CR2). PEA3 interacted with the binding element within CR2 in NCCIT cells. This study reveals the molecular details of the mechanism by which the oncogenic factor PEA3 regulates OCT4 gene expression as a transcriptional activator.

Immunohistochemical expression of four different stem cell markers in prostate cancer: High expression of NANOG in conjunction with hypoxia-inducible factor-1α expression is involved in prostate epithelial malignancy

Cancer stem cells (CSCs) have been identified in a variety of cancer types, including prostate cancer. The aim of the present study was to evaluate the immunohistochemical expression of NANOG, octamer 4 (OCT4), cluster of differentiation 133 (CD133) and NESTIN, which are all CSC markers, and assess their function in prostate carcinogenesis. A total of 114 patients were referred to the Kanazawa Medical University Hospital (Uchinada, Japan) having presented with elevated serum prostate-specific antigen levels and/or abnormal digital rectal examinations, and underwent transrectal ultrasound sonography guided eight core biopsies. The prostate pathological specimens were re-evaluated for selection in this study. When specimens were diagnosed as prostate cancer, immunohistochemical analysis of the four different stem cell markers (NANOG, OCT4, CD133 and NESTIN) and hypoxia-inducible factor (HIF)-1α was performed. Prostate cancer was found in 38 cases (33.3%), while the other patients had benign prostate hyperplasia with prostatitis. All prostate cancers were histopathologically identified as adenocarcinomas of various grades, and cancer cells and intraepithelial neoplasia (high grade) were immunohistochemically shown to express NANOG and OCT4, but not CD133 and NESTIN. The intensity of NANOG expression was much greater than that of OCT4, and the positivity and intensity of the four stem cell markers, including NANOG, were elevated with high Gleason scores. A significant correlation was observed between the NANOG- and HIF-1α-positive regions. The CSC markers, in particular OCT4 and NANOG, were immunohistochemically expressed in prostate cancers. Furthermore, HIF-1α expression may affect NANOG and/or OCT4 expression. The findings of the current study suggested that NANOG expression may be a biomarker for the diagnosis of prostate cancer, and the coexpression of NANOG and HIF-1α may be involved in prostate carcinogenesis.

Germ cell tumors of the ovary: an update

CONTEXT

The field of ovarian germ cell tumors (OGCTs) has remained relatively unchanged in the last 2 decades. However, the introduction of new stem cell pluripotency markers has provided a new understanding into the identification and taxonomy of OGCT types. New data have provided new insights into unusual teratoma-associated autoimmune disorders and the origin of gliomatosis peritonei.

OBJECTIVE

To review the impact of new pluripotency markers in the diagnosis of malignant OGCT (MOGCT) and analyze new nomenclature proposals and clinicopathologic entities.

DATA SOURCES

Ovarian germ cell tumors from routine material and expert consultation files at San Cecilio University Hospital, Granada, Spain, and the relevant literature were reviewed.

CONCLUSIONS

Although a correct diagnosis of MOGCT can often be made with histologic and classic immunohistochemical studies, the new immunohistochemical pluripotency markers give higher diagnostic accuracy. Germ cell tumors represent a caricature of the phases of normal embryonic differentiation from primordial germ and stem cells to extraembryonal and somatic tissue differentiation. Since every stage of differentiation and its related tumor type exhibit characteristic markers, the analysis of their expression facilitates tumor typing, thus complementing the use of classic antibodies. They also allow a more precise evaluation of the degree of immaturity in teratoma. The new term, primitive endodermal tumors, simplifies the understanding of the complex histology of the yolk sac tumor group, as this terminology encompasses its multiple endodermal differentiations. Recently described autoimmune encephalitis due to antibodies against the N-methyl-d-aspartate receptor has become the most frequent autoimmune disorder associated with ovarian teratoma.

Repeated ovarian stimulation does not affect the expression level of proteins involved in cell cycle control in mouse ovaries and fallopian tubes

PURPOSE

To understand if repeated cycles (2-4 rounds) of gonadotropin stimulation could affect intracellular localization/content of proteins controlling cell cycle progression in mouse fallopian tubes (FT) and ovaries.

METHODS

FT and ovaries of estrous mice (control) and of stimulated mice were analyzed to detect Oct-3/4, Sox-2, p53, β-catenin, pAKT and cyclin D1 localization/content. Spindles and chromosome alignment were analyzed in ovulated oocytes.

RESULTS

After round 4, FT and ovaries of control and stimulated groups showed no differences in Oct-3/4, Sox-2 and β-catenin localization nor in Oct-3/4, Sox-2, p53, β-catenin and pAKT contents. Cyclin D1 level increased significantly in FT of treated mice. Oocytes number decreased meanwhile frequency of abnormal meiotic spindles increased with treatments.

CONCLUSIONS

Repetitive stimulations affected oocyte spindle morphology but did not induce changes in a set of proteins involved in cell cycle progression, usually altered in ovarian cancer. The significant increase of cyclin D1 in the FT requires further investigation.

The expressions of stem cell markers: Oct4, Nanog, Sox2, nucleostemin, Bmi, Zfx, Tcl1, Tbx3, Dppa4, and Esrrb in bladder, colon, and prostate cancer, and certain cancer cell lines

Uncontrolled self-renewal plays a direct function in the progression of different types of carcinomas. The same molecular pathway that manages self-renewal in normal stem cells also seems to manage cancer stem cells. Here, we examine the expressions of self-renewal regulatory factors Oct4, Nanog, Sox2, nucleostemin, Zfx, Esrrb, Tcl1, Tbx3, and Dppa4 in tissue samples of colon, prostate, and bladder carcinomas as well as cancer cell lines HT-29, Caco-2, HT-1376, LNCaP, and HepG2. We used reverse transcriptase polymerase chain reaction to examine expressions of the above mentioned regulatory factors in cancer cell lines HT-29, Caco-2, HT-1376, LNCaP, and HepG2 and in 20 tumor tissue samples. Total RNA was isolated by the ISOGEN method. RNA integrity was checked by agarose gel electrophoresis and spectrophotometry. Expressions of Oct4 and nucleostemin at the protein level were determined by immunocytochemistry. A significant relationship was found between tumor grade and self-renewal gene expression. Expressions of stem cell specific marker genes were detected in all examined cancer cell lines, in 40% to 100% of bladder cancer samples, and in 60% to 100% of colon and prostate cancer samples. Oct4 expressed in 100% of tumor tissue samples. Our data show that stem cell markers Oct4, Nanog, Sox2, nucleostemin, Bmi, Zfx, Esrrb, Tcl1, Tbx3, and Dppa4 significantly express in cancer cell lines and cancer tissues. Hence, these markers might be useful as potential tumor markers in the diagnosis and/or prognosis of tumors.