The zinc-finger transcription factor SALL4 is frequently expressed in human cancers: association with clinical outcome in squamous cell carcinoma but not in adenocarcinoma of the esophagus

Clinicopathological characteristics of gastric adenocarcinoma with enteroblastic differentiation and gastric adenocarcinoma with enteroblastic marker expression

Gastric adenocarcinoma (GA) with enteroblastic differentiation (GAED) is an aggressive carcinoma histologically characterized by a glycogen-rich clear cytoplasm and fetal gut-like structures. GAED shows the expression of at least one of the following enteroblastic markers (EMs): glypican-3 (GPC3), spalt-like transcription factor 4 (SALL4), and α-fetoprotein (AFP). Despite the absence of clear cytoplasm, we often encounter GA with EMs expression (GA with EM); however, the clinicopathological characteristics of GA with EM remain unclear. Immunohistochemical (IHC) expression of three EMs (AFP, GPC3, and SALL4) was examined on tissue microarray. According to the status of the clear cytoplasm of tumor cells, GAs showing IHC expression of EMs were classified as either GAED or GA with EM, and this analysis categorized 688 GAs into 94 GAEDs (13.7%), 58 GAs with EM (8.4%), and 536 conventional GAs (CGAs). Both GAED and GA with EM showed frequent lymphovascular invasion, lymph node metastasis, and liver metastasis compared to CGA. However, a higher frequency of venous invasion, but not of lymphatic invasion, was noted for GAED in comparison to CGA. GAED and GA with EM showed similar overall survival. GAED had significantly poorer prognosis than CGA; however, not for GA with EM. Furthermore, GA showing EM expression had a worse prognosis than CGA. Interestingly, GA showing EM-positive group was more aggressive than CGA group as they had frequent venous invasion and liver metastasis despite its smaller tumor size. GAED and GA with EM can be clinically classified as aggressive tumors but pathologically they seem to be slightly different.

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.

Urothelial Carcinomas With Trophoblastic Differentiation, Including Choriocarcinoma: Clinicopathologic Series of 16 Cases

Trophoblastic differentiation (including choriocarcinoma) arising in urothelial carcinoma has been described in numerous case reports, but never in a single series. We present a series of these tumors, describing the morphologic spectrum, applying traditional and novel immunohistochemical stains, and characterizing clinical follow-up. We identified 16 cases, arising predominantly in the bladder (N=14), but also the ureter (N=1) and prostatic urethra (N=1). Six of our cases (38%) contained invasive urothelial carcinoma with admixed syncytiotrophoblasts, 8 cases (50%) consisted of invasive urothelial carcinoma with choriocarcinoma, 1 case (6%) showed urothelial carcinoma in situ with associated choriocarcinoma, and 1 case (6%) consisted of pure choriocarcinoma. Other subtypes of variant morphology were seen in 5 of our cases (31%) and included squamous, glandular, lipoid, chordoid/myxoid, and sarcomatoid features. Given the limited specificity of human chorionic gonadotropin immunohistochemistry, we also studied the expression of a novel specific trophoblastic marker, hydroxyl-δ-5-steroid dehydrogenase, as well as Sal-like protein 4. Human chorionic gonadotropin expression was seen in nearly all cases (93%) but was often not limited to the trophoblastic component, staining the urothelial component also in 85% of the cases. Expression of hydroxyl-δ-5-steroid dehydrogenase was more sensitive and more specific, staining 100% of the cases and limited to trophoblasts in all but 1 case. Sal-like protein 4 expression was variable, staining trophoblast in only 50% of cases and staining the urothelial carcinoma component in 43% of those positive cases. Most of our tumors presented at a high stage and were associated with poor clinical outcomes, with at least muscle-invasive disease (pT2) in 10 of the 14 bladder tumors (71%), periureteric fat invasion in the ureter tumor (pT3), distant metastases in 7 of 16 cases (44%) and death of disease in 3 of the 15 patients with follow-up (20%). Our study describes a series of urothelial carcinomas with trophoblastic differentiation, demonstrating the morphologic spectrum of this entity, its frequent association with other subtypes of variant morphology, its characteristic immunoprofile, and its aggressive clinical behavior.

Phosphorylation of TFCP2L1 by CDK1 is required for stem cell pluripotency and bladder carcinogenesis

Molecular programs involved in embryogenesis are frequently upregulated in oncogenic dedifferentiation and metastasis. However, their precise roles and regulatory mechanisms remain elusive. Here, we showed that CDK1 phosphorylation of TFCP2L1, a pluripotency-associated transcription factor, orchestrated pluripotency and cell-cycling in embryonic stem cells (ESCs) and was aberrantly activated in aggressive bladder cancers (BCs). In murine ESCs, the protein interactome and transcription targets of Tfcp2l1 indicated its involvement in cell cycle regulation. Tfcp2l1 was phosphorylated at Thr177 by Cdk1, which affected ESC cell cycle progression, pluripotency, and differentiation. The CDK1-TFCP2L1 pathway was activated in human BC cells, stimulating their proliferation, self-renewal, and invasion. Lack of TFCP2L1 phosphorylation impaired the tumorigenic potency of BC cells in a xenograft model. In patients with BC, high co-expression of TFCP2L1 and CDK1 was associated with unfavorable clinical characteristics including tumor grade, lymphovascular and muscularis propria invasion, and distant metastasis and was an independent prognostic factor for cancer-specific survival. These findings demonstrate the molecular and clinical significance of CDK1-mediated TFCP2L1 phosphorylation in stem cell pluripotency and in the tumorigenic stemness features associated with BC progression.

Immunohistochemical Pitfalls in Genitourinary Pathology: 2018 Update

Immunohistochemistry may be a very useful adjunct to morphologic diagnosis in many areas of surgical pathology, including genitourinary pathology. In this review, we address common diagnostic dilemmas where immunophenotypic analysis may be utilized and we highlight pitfalls specific to each scenario. For prostate, we review the diagnosis of limited prostatic adenocarcinoma and the distinction of high-grade prostatic adenocarcinoma from urothelial carcinoma. We also cover markers of urothelial lineage in the diagnosis of metastatic carcinoma of unknown primary site. In the kidney, distinction of poorly differentiated renal cell carcinoma from urothelial carcinoma and epithelioid angiomyolipoma, adjuncts to the recognition of hereditary renal neoplasia, and the diagnosis of metastatic renal cell carcinoma are discussed. Finally, for testis we address distinction of germ cell tumors from sex cord-stromal tumors, as well as the diagnosis of metastatic germ cell tumors.

The International Stem Cell Initiative, Allison TF, Andrews PW, Avior Y, Barbaric I, Benvenisty N, Bock C, Brehm J, Brüstle O, Damjanov I, Elefanty A, Felkner D, Gokhale PJ, Halbritter F, Healy LE, Hu TX, Knowles BB, Loring JF, Ludwig TE, Mayberry R, Micallef S, Mohamed JS, Müller FJ, Mummery CL, Nakatsuji N, Ng ES, Oh SKW, O’Shea O, Pera MF, Reubinoff B, Robson P, Rossant J, Schuldt BM, Solter D, Sourris K, Stacey G, Stanley EG, Suemori H, Takahashi K, Yamanaka S. Assessment of established techniques to determine developmental and malignant potential of human pluripotent stem cells

The International Stem Cell Initiative compared several commonly used approaches to assess human pluripotent stem cells (PSC). PluriTest predicts pluripotency through bioinformatic analysis of the transcriptomes of undifferentiated cells, whereas, embryoid body (EB) formation in vitro and teratoma formation in vivo provide direct tests of differentiation. Here we report that EB assays, analyzed after differentiation under neutral conditions and under conditions promoting differentiation to ectoderm, mesoderm, or endoderm lineages, are sufficient to assess the differentiation potential of PSCs. However, teratoma analysis by histologic examination and by TeratoScore, which estimates differential gene expression in each tumor, not only measures differentiation but also allows insight into a PSC's malignant potential. Each of the assays can be used to predict pluripotent differentiation potential but, at this stage of assay development, only the teratoma assay provides an assessment of pluripotency and malignant potential, which are both relevant to the pre-clinical safety assessment of PSCs.

HER2 is frequently overexpressed in hepatoid adenocarcinoma and gastric carcinoma with enteroblastic differentiation: a comparison of 35 cases to 334 gastric carcinomas of other histological types

AIMS

α-Fetoprotein (AFP)-producing gastric carcinoma (AFPGC) is one of the most aggressive GC subtypes. Frequent expression of human epidermal growth factor receptor 2 (HER2) has previously been reported in hepatoid adenocarcinoma (HAC), a major histological subtype of AFPGC originating from common-type GC (CGC). However, HER2 expression levels in other AFPGC histological subtypes are unknown. In this study, we analysed HER2 expression in GCs with primitive phenotypes in addition to HAC.

METHODS

HER2 expression was evaluated in representative complete sections from 16 HACs, 19 GCs with enteroblastic differentiation (GCEDs) and 334 GCs of other histological types as controls. The Ruschoff/Hofmann method was used to score HER2 immunohistochemistry. Samples with a HER2 score of 2+ were further assessed using fluorescence in situ hybridisation. Oncofetal protein (OFP) expression in HAC and GCED was tested via immunohistochemical staining for AFP, glypican 3 and Sal-like protein 4.

RESULTS

Thirty of 35 HAC/GCED cases comprised more than two histological patterns. The HER2 positivity rates of each histological component in the HACs/GCEDs were 25.0% for HAC (n=16), 34.6% for GCED (n=26) and 48.1% for CGC (n=27), which were higher than those of the control group (13.8%). Additionally, the majority of CGC components in HACs/GCEDs were positive for OFP (88.9%).

CONCLUSIONS

HER2 is frequently overexpressed not only in HAC but also in GCED and CGC components of HACs/GCEDs, which suggests an association between HER2 and OFP expression. Moreover, our findings suggest that HER2-positive CGC has a higher risk of progression to HAC/GCED than HER2-negative GC.

Oncofetal gene SALL4 and prognosis in cancer: A systematic review with meta-analysis

The Spalt-Like Transcription Factor 4 (SALL4) oncogene plays a central function in embryo-fetal development and is absent in differentiated tissues. Evidence suggests that it can be reactivated in several cancers worsening the prognosis. We aimed at investigating the risk associated with SALL4 reactivation for all-cause mortality and recurrence in cancer using the current literature. A PubMed and SCOPUS search until 1st September 2016 was performed, focusing on perspective studies reporting prognostic parameters in cancer data. In addition, 17 datasets of different cancer types from The Cancer Genome Atlas were considered. A total of 9,947 participants across 40 cohorts, followed-up for about 5 years on average, were analyzed comparing patients showing SALL4 presence (SALL4+, n = 1,811) or absence (SALL4-, n = 8,136). All data were summarised using risk ratios (RRs) for the number of deaths/recurrences and hazard ratios (HRs) for the time-dependent risk related to SALL4+, adjusted for potential confounders. SALL4+ significantly increased overall mortality (RR = 1.34, 95% confidence intervals (CI)=1.21-1.48, p<0.0001, I2=66%; HR=1.4; 95%CI: 1.19-1.65; p<0.0001; I2=63%) and recurrence of disease (RR = 1.25, 95% CI = 1.1-1.42, p=0.0006, I2=62%); HR=1.52; 95% CI: 1.22-1.89, p=0.0002; I2=69%) compared to SALL4-. Moreover, SALL4 remained significantly associated with poor prognosis even using HRs adjusted for potential confounders (overall mortality: HR=1.4; 95%CI: 1.19-1.65; p<0.0001; I2=63%; recurrence of disease: HR=1.52; 95% CI: 1.22-1.89, p=0.0002; I2=69%). These results suggest that SALL4 expression increases both mortality and recurrence of cancer, confirming this gene as an important prognostic marker and a potential target for personalized medicine.