Clear cell carcinoma of the pancreas: histopathologic features and a unique biomarker: hepatocyte nuclear factor-1beta

Novel Ultrastructural Insights into the Clear-Cell Carcinoma of the Pancreas: A Case Report

Pancreatic cancer, most frequently as ductal adenocarcinoma (PDAC), is the third leading cause of cancer death. Clear-cell primary adenocarcinoma of the pancreas (CCCP) is a rare, aggressive, still poorly characterized subtype of PDAC. We report here a case of a 65-year-old male presenting with pancreatic neoplasia. A histochemical examination of the tumor showed large cells with clear and abundant intracytoplasmic vacuoles. The clear-cell foamy appearance was not related to the hyperproduction of mucins. Ultrastructural characterization with transmission electron microscopy revealed the massive presence of mitochondria in the clear-cell cytoplasm. The mitochondria showed disordered cristae and various degrees of loss of structural integrity. Immunohistochemistry staining for NADH dehydrogenase [ubiquinone] 1 alpha subcomplex, 4-like 2 (NDUFA4L2) proved specifically negative for the clear-cell tumor. Our ultrastructural and molecular data indicate that the clear-cell nature in CCCP is linked to the accumulation of disrupted mitochondria. We propose that this may impact on the origin and progression of this PDAC subtype.

Extensive germline-somatic interplay contributes to prostate cancer progression through HNF1B co-option of TMPRSS2-ERG

Genome-wide association studies have identified 270 loci conferring risk for prostate cancer (PCa), yet the underlying biology and clinical impact remain to be investigated. Here we observe an enrichment of transcription factor genes including HNF1B within PCa risk-associated regions. While focused on the 17q12/HNF1B locus, we find a strong eQTL for HNF1B and multiple potential causal variants involved in the regulation of HNF1B expression in PCa. An unbiased genome-wide co-expression analysis reveals PCa-specific somatic TMPRSS2-ERG fusion as a transcriptional mediator of this locus and the HNF1B eQTL signal is ERG fusion status dependent. We investigate the role of HNF1B and find its involvement in several pathways related to cell cycle progression and PCa severity. Furthermore, HNF1B interacts with TMPRSS2-ERG to co-occupy large proportion of genomic regions with a remarkable enrichment of additional PCa risk alleles. We finally show that HNF1B co-opts ERG fusion to mediate mechanistic and biological effects of the PCa risk-associated locus 17p13.3/VPS53/FAM57A/GEMIN4. Taken together, we report an extensive germline-somatic interaction between TMPRSS2-ERG fusion and genetic variations underpinning PCa risk association and progression.

Primary Clear Cell Carcinoma of the Pancreas: A Rare Case Report

Most pancreatic carcinoma is ductal adenocarcinoma. Primary pancreatic clear cell carcinomas composed almost entirely of clear tumor cells are very rare. We present a case of a 72-year-old man with a pancreatic mass, which was detected on abdominal computed tomography (CT). He had no symptoms and no abnormal findings on physical examination; however, he had a history of hepatitis B, hepatitis C, and hepatocellular carcinoma. He had received anti-viral treatment and radiofrequency ablation twice until 2 years prior. One year prior, follow-up contrast-enhanced abdominal CT revealed a newly developed pancreatic mass. Laparoscopic radical antegrade modular pancreato-splenectomy was performed. An ill-defined white-to-tan firm solid mass was observed in the pancreas, approximately 4.3 cm in diameter. The tumor cells showed >95% clear cell features, with a large round to oval nuclei and abundant clear cytoplasms, and well-defined cell membranes. Immunohistochemical staining revealed that the tumor cells were positive for cytokeratin 7, cytokeratin 19, HNF-1β, MUC-1, and p53. We excluded the possibility of metastatic clear renal cell carcinoma, neuroendocrine carcinoma, perivascular epithelioid cell tumor, malignant melanoma, and sarcoma because of the negativity for vimentin, chromogranin, synaptophysin, and HMB45. Consequently, he was diagnosed as having primary clear cell carcinoma of the pancreas and was treated with postoperative radiotherapy. Two months later, abdominal CT was suspicious for local recurrence at the resection margin. Additional adjuvant FOLFIRINOX chemotherapy was carried out 12 times. The patient is still alive after his third radiofrequency ablation for the newly-developed hepatic mass. Immunohistochemical staining for MUC-1 and HNF-1β, as well as histologic feature is very helpful for the diagnosis of primary pancreatic clear cell carcinoma with imaging methods for metastasis exclusion.

Type 2 Diabetes-Related Variants Influence the Risk of Developing Prostate Cancer: A Population-Based Case-Control Study and Meta-Analysis

In this study, we have evaluated whether 57 genome-wide association studies (GWAS)-identified common variants for type 2 diabetes (T2D) influence the risk of developing prostate cancer (PCa) in a population of 304 Caucasian PCa patients and 686 controls. The association of selected single nucleotide polymorphisms (SNPs) with the risk of PCa was validated through meta-analysis of our data with those from the UKBiobank and FinnGen cohorts, but also previously published genetic studies. We also evaluated whether T2D SNPs associated with PCa risk could influence host immune responses by analysing their correlation with absolute numbers of 91 blood-derived cell populations and circulating levels of 103 immunological proteins and 7 steroid hormones. We also investigated the correlation of the most interesting SNPs with cytokine levels after in vitro stimulation of whole blood, peripheral mononuclear cells (PBMCs), and monocyte-derived macrophages with LPS, PHA, Pam3Cys, and Staphylococcus Aureus. The meta-analysis of our data with those from six large cohorts confirmed that each copy of the FTO_rs9939609A, HNF1B_rs7501939T, HNF1B_rs757210T, HNF1B_rs4430796G, and JAZF1_rs10486567A alleles significantly decreased risk of developing PCa (p = 3.70 × 10^-5, p = 9.39 × 10^-54, p = 5.04 × 10^-54, p = 1.19 × 10^-71, and p = 1.66 × 10^-18, respectively). Although it was not statistically significant after correction for multiple testing, we also found that the NOTCH2_rs10923931T and RBMS1_rs7593730 SNPs associated with the risk of developing PCa (p = 8.49 × 10^-4 and 0.004). Interestingly, we found that the protective effect attributed to the HFN1B locus could be mediated by the SULT1A1 protein (p = 0.00030), an arylsulfotransferase that catalyzes the sulfate conjugation of many hormones, neurotransmitters, drugs, and xenobiotic compounds. In addition to these results, eQTL analysis revealed that the HNF1B_rs7501939, HNF1B_rs757210, HNF1B_rs4430796, NOTCH2_rs10923931, and RBMS1_rs7593730 SNPs influence the risk of PCa through the modulation of mRNA levels of their respective genes in whole blood and/or liver. These results confirm that functional TD2-related variants influence the risk of developing PCa, but also highlight the need of additional experiments to validate our functional results in a tumoral tissue context.

Current Pathology Model of Pancreatic Cancer

Pancreatic cancer (PC) is one of the most aggressive and lethal malignant neoplasms, ranking in seventh place in the world in terms of the incidence of death, with overall 5-year survival rates still below 10%. The knowledge about PC pathomechanisms is rapidly expanding. Daily reports reveal new aspects of tumor biology, including its molecular and morphological heterogeneity, explain complicated "cross-talk" that happens between the cancer cells and tumor stroma, or the nature of the PC-associated neural remodeling (PANR). Staying up-to-date is hard and crucial at the same time. In this review, we are focusing on a comprehensive summary of PC aspects that are important in pathologic reporting, impact patients' outcomes, and bring meaningful information for clinicians. Finally, we show promising new trends in diagnostic technologies that might bring a difference in PC early diagnosis.

The biology of pancreatic cancer morphology

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal of all human malignancies. PDAC precursor lesions, invasive primary PDAC, and metastatic PDAC each display distinct morphologies that reflect unique biology. This 'biomorphology' is determined by a complex neoplastic history of clonal phylogenetic relationships, geographic locations, external environmental exposures, intrinsic metabolic demands, and tissue migration patterns. Understanding the biomorphological evolution of PDAC progression is not only of academic interest but also of great practical value. Applying this knowledge to surgical pathology practice facilitates the correct diagnosis on routine H&E stains without additional ancillary studies in most cases. Here I provide a concise overview of the entire biomorphological spectrum of PDAC progression beginning with initial neoplastic transformation and ending in terminal distant metastasis. Most biopsy and resection specimens are currently obtained prior to treatment. As such, our understanding of untreated PDAC biomorphology is mature. The biomorphology of treated PDAC is less defined but will assume greater importance as the frequency of neoadjuvant therapy increases. Although this overview is slanted towards pathology, it is written so that pathologists, clinicians, and scientists alike might find it instructive for their respective disciplines.

Nicotinamide N-Methyltransferase: An Emerging Protagonist in Cancer Macro(r)evolution

Nicotinamide N-methyltransferase (NNMT) has progressed from being considered merely a Phase II metabolic enzyme to one with a central role in cell function and energy metabolism. Over the last three decades, a significant body of evidence has accumulated which clearly demonstrates a central role for NNMT in cancer survival, metastasis, and drug resistance. In this review, we discuss the evidence supporting a role for NNMT in the progression of the cancer phenotype and how it achieves this by driving the activity of pro-oncogenic NAD+-consuming enzymes. We also describe how increased NNMT activity supports the Warburg effect and how it promotes oncogenic changes in gene expression. We discuss the regulation of NNMT activity in cancer cells by both post-translational modification of the enzyme and transcription factor binding to the NNMT gene, and describe for the first time three long non-coding RNAs which may play a role in the regulation of NNMT transcription. We complete the review by discussing the development of novel anti-cancer therapeutics which target NNMT and provide insight into how NNMT-based therapies may be best employed clinically.

Primary Clear Cell Carcinoma of the Pancreas: A Systematic Review

Over the years, the world has witnessed many advances in diagnosing and treating multiple types of cancers. These breakthroughs have revolutionized the understanding of the molecular drive behind these neoplasms, leading to tangible therapeutic evolution and promising prognostic implications. However, pancreatic cancer remains a highly lethal disease. With recent discoveries, modern medicine has been able to delineate histopathologic subtypes of pancreatic cancer in hopes of improved diagnosis and treatment to improve survival. A once vague entity, clear cell adenocarcinoma of the pancreas, in particular, has been better characterized on a histopathological and molecular level over the past two decades. With novel technological support, this disease has become less inconspicuous, and more researchers have reported its occurrence. Its diagnosis relies heavily on a mix of histological and immunohistochemical clues such as a clear cell cytoplasm and positivity for cytokeratins and other markers. However, new molecular markers, such as hepatocyte nuclear factor 1 beta, have been associated with this entity and may aid in further diagnostic and therapeutic strategies. This review article aims to portray how the identification and description of clear cell adenocarcinoma of the pancreas have evolved over the past few decades and how this may impact future treatment strategies.

HNF-1β is a More Sensitive and Specific Marker Than C-Reactive Protein for Identifying Biliary Differentiation in Primary Hepatic Carcinomas

CONTEXT.—

Intrahepatic cholangiocarcinoma (iCCA) needs to be distinguished from hepatocellular carcinoma (HCC) and metastasis, and in the absence of any specific biliary markers, is often a diagnosis of exclusion. Hepatocyte nuclear factor (HNF)-1β is a transcription factor that plays a critical role in bile duct system morphogenesis.

OBJECTIVE.—

To investigate the diagnostic value of HNF-1β to differentiate iCCA from HCC by immunohistochemistry and compare HNF-1β with C-reactive protein (CRP), a previously identified marker for iCCA.

DESIGN.—

Cases of iCCA (n = 75), combined hepatocellular-cholangiocarcinoma (cHCC-CCA) (n = 13) and HCC (n = 65) were included in the study.

RESULTS.—

All cases of iCCA (74 of 74, 100%) expressed HNF-1β compared with CRP expressed in 72.60% (53 of 73). The sensitivity and specificity of HNF-1β to differentiate iCCA from HCC was 100% and 92.31%, whereas the sensitivity and specificity for CRP was 75.58% and 7.79%. The expression of HNF-1β was greater in iCCA and the CCA component of cHCC-CCA compared with CRP (87 of 87, 100% versus 65 of 86, 75.58%, P < .001). On the contrary, CRP was more frequently expressed compared with HNF-1β in HCC and HCC component of cHCC-CCA (71 of 77, 92.21% versus 6 of 78, 7.69%; P < .001).

CONCLUSIONS.—

Our data indicate that HNF-1β is a more sensitive and specific marker than CRP for the diagnosis of iCCA and to identify the CCA component in cHCC-CCA. Lack of HNF-1β expression may be used to exclude iCCA from consideration in cases of adenocarcinomas of unknown primary.

Hepatocyte nuclear factor 1 beta: A perspective in cancer

Hepatocyte nuclear factor 1 beta (HNF1 β/B) exists as a homeobox transcription factor having a vital role in the embryonic development of organs mainly liver, kidney and pancreas. Initially described as a gene causing maturity‐onset diabetes of the young (MODY), HNF1β expression deregulation and single nucleotide polymorphisms in HNF1β have now been associated with several tumours including endometrial, prostate, ovarian, hepatocellular, renal and colorectal cancers. Its function has been studied either as homodimer or heterodimer with HNF1α. In this review, the role of HNF1B in different cancers will be discussed along with the role of its splice variants, and its emerging role as a potential biomarker in cancer.

Clear cell adenocarcinoma presenting as acute pancreatitis: A rare form of primary pancreatic malignancy

BACKGROUND

Pancreatic cancer is associated with a dismal prognosis, with ductal adenocarcinoma being the most common form of primary neoplasm diagnosed. Clear cell carcinoma is usually associated with kidney, ovarian or bladder malignancy but rarely associated with pancreatic malignancy. According to the WHO classification, primary clear cell adenocarcinoma of the pancreas is a rare "miscellaneous" carcinoma, and to date few cases have been reported in the literature.

CASE

A 63-year old female who presented to a metropolitan hospital in Australia with abdominal pain suggestive of pancreatitis. Abdominal computed tomography subsequently demonstrated a necrotic mass in the neck of the pancreas with hepatic metastasis. Subsequent histopathological and immunohistochemical analysis was consistent with pancreatic clear cell adenocarcinoma. The patient was discharged to home to commence on dose reduced nab-paclitaxel and gemcitabine.

CONCLUSION

This case reports a rare variant of pancreatic malignancy and contributes further evidence to the body of literature highlighting clear cell adenocarcinoma as a histological subtype of pancreatic neoplasm, albeit rare in nature.

DNMT1 recruited by EZH2-mediated silencing of miR-484 contributes to the malignancy of cervical cancer cells through MMP14 and HNF1A

BACKGROUND

Emerging evidence indicates that dysregulation of microRNAs (miRNAs) contributes to cervical cancer (CC) tumorigenesis and development. Previous work showed that miR-484 which regulated the EMT process was obviously downregulated in CC. However, little is known about the precise mechanism.

RESULTS

We found that the deficiency of EZH2-recruited DNA methyltransferases DNMT1 reduced the CpG methylation of miR-484 promoter and then increased the miR-484 expression. Furthermore, the cell membrane-bound matrix metalloproteinase (MMP14) and the hepatocyte nuclear factor 1A (HNF1A) were found to be downregulated by miR-484. miR-484 repressed the expression of MMP14 and HNF1A inhibiting CC growth and metastasis in vitro and in vivo. Upregulation of MMP14 and HNF1A promotes the CC cell adhesion and EMT, all of which contribute to cell motility and metastasis. Moreover, miR-484 negatively regulates the WNT/MAPK and TNF signaling pathway by downregulating HNF1A and MMP14 respectively. Thus, miR-484, who is downregulated by DNMT1-mediated hypermethylation in its promoter, functions as a tumor suppressor by inhibiting MMP14 and HNF1A expression in CC.

CONCLUSION

Our finding characterizes miR-484 as a key suppressive regulator in CC metastasis and reveals a DNMT1-mediated epigenetic mechanism for miR-484 silencing, expanding our understanding of the molecular mechanism underlying CC progression and metastasis.

Primary signet ring cell carcinoma of the pancreas: Cytopathology review of a rare entity

Primary signet ring cell carcinoma of the pancreas (PSRCCP) is an extremely rare diagnosis that has not been extensively studied in literature. Primary and metastatic neoplasms to the pancreas may exhibit cytomorphological similarities to signet ring cells, posing diagnostic challenges. In this article, we review PSRCCP and provide a study of several primary pancreatic neoplasms that may mimic the appearance of PSRCCP upon cytopathology evaluation, shedding light on the existence of this dilemma, and helping cytopathologists in navigating similar scenarios in their practice.

Absence of HIF1A Leads to Glycogen Accumulation and an Inflammatory Response That Enables Pancreatic Tumor Growth

Cancer cells respond to hypoxia by upregulating the hypoxia-inducible factor 1α (HIF1A) transcription factor, which drives survival mechanisms that include metabolic adaptation and induction of angiogenesis by VEGF. Pancreatic tumors are poorly vascularized and severely hypoxic. To study the angiogenic role of HIF1A, and specifically probe whether tumors are able to use alternative pathways in its absence, we created a xenograft mouse tumor model of pancreatic cancer lacking HIF1A. After an initial delay of about 30 days, the HIF1A-deficient tumors grew as rapidly as the wild-type tumors and had similar vascularization. These changes were maintained in subsequent passages of tumor xenografts in vivo and in cell lines ex vivo. There were many cancer cells with a "clear-cell" phenotype in the HIF1A-deficient tumors; this was the result of accumulation of glycogen. Single-cell RNA sequencing (scRNA-seq) of the tumors identified hypoxic cancer cells with inhibited glycogen breakdown, which promoted glycogen accumulation and the secretion of inflammatory cytokines, including interleukins 1β (IL1B) and 8 (IL8). scRNA-seq of the mouse tumor stroma showed enrichment of two subsets of myeloid dendritic cells (cDC), cDC1 and cDC2, that secreted proangiogenic cytokines. These results suggest that glycogen accumulation associated with a clear-cell phenotype in hypoxic cancer cells lacking HIF1A can initiate an alternate pathway of cytokine and DC-driven angiogenesis. Inhibiting glycogen accumulation may provide a treatment for cancers with the clear-cell phenotype. SIGNIFICANCE: These findings establish a novel mechanism by which tumors support angiogenesis in an HIF1α-independent manner.

Two Cases of Rare Pancreatic Malignancies

Background: Pancreatic adenocarcinoma remains one of the most lethal malignancies with little treatment advancements. Other less common pancreatic cancer histologies have different outcomes and disease course. In this article, we report two cases of rare pancreatic tumors.

Presentation: The first case is a 59-year old, who was undergoing surveillance of a known pancreatic cyst, which eventually enlarged. The mass was resected and pathology revealed undifferentiated carcinoma with osteoclast-like giant cells. The patient did not receive any adjuvant therapy and has had no recurrence. The second case is of a 60-year-old patient who presented with signs and symptoms of pancreatic insufficiency and was found to have clear cell adenocarcinoma of the pancreas. She received neoadjuvant chemoradiotherapy followed by surgical resection without complications.

Conclusion: Our article presents these rare malignancies, which had outcomes that are more encouraging than typical adenocarcinomas. Genomic sequencing can provide more insight into these tumors and potentially provide targets for therapy.

Glucose and Lactate Transport in Pancreatic Cancer: Glycolytic Metabolism Revisited

Membrane transporters fulfill essential roles in maintaining normal cellular function in health. In cancer, transporters likewise facilitate the aberrant characteristics typical of proliferating tumor cells. Pancreatic ductal adenocarcinoma is remarkable in its aggressiveness, and its metabolism is supported by a variety of membrane transporters. Glucose transporter 1 is upregulated in pancreatic cancer, enables rapid cellular uptake of glucose, and contributes to the invasiveness and metastatic ability of the disease. Likewise, the machinery of glycolysis, enzymes such as pyruvate kinase type M2 and hexokinase 2, is particularly active and ultimately leads to both lactate and tumor formation. Lactic acid channels and transporters include monocarboxylate transporters 1 and 4, connexin43, and CD147. In conjunction with glucose transporters and glycolytic metabolism, lactic acid transport helps perpetuate tumor cell metabolism and contributes to the formation of the unique tumor microenvironment in pancreatic cancer. These transporters may serve as potential therapeutic targets.

Primary clear cell adenocarcinoma of the pancreas: a case report and literature update

Primary clear cell carcinoma of pancreas is extremely rare. We present a case of a 64-year-old male with a mass in the distal body and tail of the pancreas. He underwent a distal pancreatectomy. The histopathology of tumor cells showed features with abundant clear cytoplasm and prominent cell boundaries. Immunohistochemical analysis of neoplastic cells showed reactions to antibodies against cytokeratin-7 and showed no reactions to antibodies against hepatocyte nuclear factor-1β, carbonic anhydrase 9, synaptophysin, and chromogranin A. The patient was subsequently diagnosed with a primary clear cell carcinoma of the pancreas. This is the first time we have encountered it. We report this rare case and update the current literature of this tumor.

Investigation of HNF-1B as a diagnostic biomarker for pancreatic ductal adenocarcinoma

Background

Diagnosing pancreatic ductal adenocarcinoma (PDAC) in the setting of metastasis with an unknown primary remains very challenging due to the lack of specific biomarkers. HNF-1B has been characterized as an important transcription factor for pancreatic development and was reported as a biomarker for clear cell subtype of PDAC.

Methods

To investigate the diagnostic role of HNF-1B for PDAC, we used tissue microarray (TMA) and immunohistochemistry (IHC) to characterize HNF-1B expression in a large cohort of carcinomas, including 127 primary PDACs, 47 biliary adenocarcinomas, 17 metastatic PDACs, and 231 non-pancreaticobiliary carcinomas.

Results

HNF-1B was expressed in 107 of 127 (84.3%) of PDACs, 13 of 15 (86.7%) of cholangiocarcinomas, 13 of 18 (72%) of ampullary carcinomas, and 13 of 14 (92.9%) of gallbladder adenocarcinomas. Notably, HNF-1B was expressed in 16 of 17 (94.1%) of metastatic PDACs. Among the non-pancreaticobiliary cancers, HNF-1B was expressed in ~ 77% clear cell carcinomas of the kidney and ovarian clear cell carcinomas. Gastroesophageal, lung, and prostate adenocarcinomas occasionally expressed HNF-1B in up to 37% cases. HNF-1B was completely negative in hepatocellular, colorectal, breast, and lung squamous cell carcinomas. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of HNF-1B for primary pancreaticobiliary carcinoma is 84, 68, 66, 85, and 75%, respectively. HNF-1B expression was not significantly associated with overall survival in patients with PDAC, but tumor size ≥2 cm and high tumor grade were significantly associated with worse overall survival in multivariate analyses.

Conclusions

HNF-1B may be used in surgical pathology to aid the diagnosis of metastatic pancreatic and biliary carcinoma with a panel of other markers to exclude lung, kidney, prostate, and Müllerian origins.

Systemic Chemotherapy for Advanced Rare Pancreatic Histotype Tumors: A Retrospective Multicenter Analysis

OBJECTIVES

Two issues were put forth by clinicians in the management of the advanced stages of rare variants of pancreatic ductal adenocarcinoma and other exocrine histotypes with peculiar clinical and pathological features: Do chemotherapy regimens recommended in pancreatic ductal adenocarcinoma patients have a clinical activity in rare pancreatic tumors? Or should other chemotherapy combinations be considered in this subset of patients?

METHODS

We conducted a multicenter retrospective study that collected data from 2005 to 2016 at 14 Italian cancer centers with the aim to evaluate tumor response and time to progression for first- and second-line and overall survival.

RESULTS

Of approximately 4300 exocrine pancreatic cancer patients, 79 advanced cases affected by rare histological types were identified, with pancreatic acinar cell cancer (n = 23), pancreatic adenosquamous cancer (n = 16), and mucinous cystic neoplasm with an associated invasive mucinous cystadenocarcinoma (n = 15) most represented. Survival analyses for each subgroup in relation with the different chemotherapy regimens showed the lack of statistical significance correlations.

CONCLUSIONS

Because of the lack of clinical trials in patients affected by these rare pancreatic histotypes, only their molecular classification would help clinicians in future therapeutic choice.

Role of HNF1β in the differential diagnosis of yolk sac tumor from other germ cell tumors

Identification of the yolk sac tumor (YST) component in germ cell tumors (GCT) may prove challenging, and highly sensitive and specific immunohistochemical markers are still lacking. Preliminary data from the literature suggest that HNF1β may represent a sensitive marker of YST. The specificity of HNF1β has not been addressed in GCT. A cohort of 49 YST specimens from 45 patients was designed, occurring either as pure tumors, or as a component of a mixed GCT. Immunohistochemistry was conducted on whole tumor sections using HNF1β. SALL4, OCT4, CD30, CDX2, Cytokeratin 19, Glypican 3, and GATA3 were used for classification of the GCT components. Patients were mostly male (39/45), aged 14 months to 49 years, with primary testicular tumors (37/39), or primary mediastinal pure YSTs (2/39). All 6 primary tumors occurring in females (6/45) were pure ovarian YSTs; age range was 4 to 72 years. HNF1β nuclear reactivity was seen in the YST component in all 49 tumors, with a moderate to strong nuclear pattern of staining. Embryonal carcinoma (EC, 0/32) and seminoma (0/6) were negative. Choriocarcinoma (6/6) showed faint focal cytoplasmic reactivity to HNF1β but no nuclear staining. In teratomas, only enteric-type glands showed nuclear reactivity to HNF1β (11/16). Therefore, HNF1β sensitivity in YST component identification was 100% and specificity was 80%. Thus, in our experience, HNF1β is a sensitive and reliable marker of the YST component in GCT, and allows distinction of YST from intricately admixed EC, especially in the diffuse embryoma pattern.

Development of Cell-Permeable, Non-Helical Constrained Peptides to Target a Key Protein-Protein Interaction in Ovarian Cancer

There is a lack of current treatment options for ovarian clear cell carcinoma (CCC) and the cancer is often resistant to platinum-based chemotherapy. Hence there is an urgent need for novel therapeutics. The transcription factor hepatocyte nuclear factor 1β (HNF1β) is ubiquitously overexpressed in CCC and is seen as an attractive therapeutic target. This was validated through shRNA-mediated knockdown of the target protein, HNF1β, in five high- and low-HNF1β-expressing CCC lines. To inhibit the protein function, cell-permeable, non-helical constrained proteomimetics to target the HNF1β-importin α protein-protein interaction were designed, guided by X-ray crystallographic data and molecular dynamics simulations. In this way, we developed the first reported series of constrained peptide nuclear import inhibitors. Importantly, this general approach may be extended to other transcription factors.

Systematic review of peri-operative prognostic biomarkers in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) continues to be associated with a poor prognosis. This systematic review aimed to summarize the literature regarding potential prognostic biomarkers to facilitate validation studies and clinical application.

METHODS

A systematic review was performed (2004-2014) according to PRISMA guidelines. Studies were ranked using REMARK criteria and the following outcomes were examined: overall/disease free survival, nodal involvement, tumour characteristics, metastasis, recurrence and resectability.

RESULTS

256 biomarkers were identified in 158 studies. 171 biomarkers were assessed with respect to overall survival: urokinase-type plasminogen activator receptor, atypical protein kinase C and HSP27 ranked the highest. 33 biomarkers were assessed for disease free survival: CD24 and S100A4 were the highest ranking. 17 biomarkers were identified for lymph node involvement: Smad4/Dpc4 and FOXC1 ranked highest. 13 biomarkers were examined for tumour grade: mesothelin and EGFR were the highest ranking biomarkers. 10 biomarkers were identified for metastasis: p16 and sCD40L were the highest ranking. 4 biomarkers were assessed resectability: sCD40L, s100a2, Ca 19-9, CEA.

CONCLUSION

This review has identified and ranked specific biomarkers that should be a primary focus of ongoing validation and clinical translational work in PDAC.

Metastatic Renal Cell Carcinoma to the Pancreas: A Review

The pancreas is an unusual site for tumor metastasis, accounting for only 2% to 5% of all malignancies affecting the pancreas. The more common metastases affecting the pancreas include renal cell carcinomas, melanomas, colorectal carcinomas, breast carcinomas, and sarcomas. Although pancreatic involvement by nonrenal malignancies indicates widespread systemic disease, metastatic renal cell carcinoma to the pancreas often represents an isolated event and is thus amenable to surgical resection, which is associated with long-term survival. As such, it is important to accurately diagnose pancreatic involvement by metastatic renal cell carcinoma on histology, especially given that renal cell carcinoma metastasis may manifest more than a decade after its initial presentation and diagnosis. In this review, we discuss the clinicopathologic findings of isolated renal cell carcinoma metastases of the pancreas, with special emphasis on separating metastatic renal cell carcinoma and its various differential diagnoses in the pancreas.

ARHGEF15 overexpression worsens the prognosis in patients with pancreatic ductal adenocarcinoma through enhancing the motility and proliferative activity of the cancer cells

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive neoplastic diseases, associated with a remarkably poor prognosis. However, the molecular mechanisms underlying the development of PDAC remain elusive. The aim of this study was to identify genes whose expressions are correlated with a poor prognosis in PDAC patients, and to unravel the mechanisms underlying the involvement of these genes in the development of the cancer.

METHODS

Global gene expression profiling was conducted in 39 specimens obtained from Japanese patients with PDAC to identify genes whose expressions were correlated with a shorter overall survival. The effect of gene silencing or overexpression of ARHGEF15 in pancreatic cancer cell lines was examined by introducing siRNAs of ARHGEF15 or the ARHGEF15 expression vector. After assessing the effect of ARHGEF15 deregulation on the Rho-family proteins by pull-down assay, wound healing, transwell and cell viability assays were carried out to investigate the cellular phenotypes caused by the perturbation.

RESULTS

The global mRNA expression profiling revealed that overexpression of ARHGEF15, a Rho-specific GEF, was significantly associated with a poor prognosis in patients with PDAC. We also found that the depletion of ARHGEF15 by RNA interference in pancreatic cancer cell lines downregulated the activities of molecules of the Rho signaling pathway, including RhoA, Cdc42 and Rac1. Then, we also showed that ARHGEF15 silencing significantly reduced the motility and viability of the cells, while its overexpression resulted in the development of the opposite phenotype in multiple pancreatic cancer cell lines.

CONCLUSION

These data suggest that upregulation of ARHGEF15 contributes to the development of aggressive PDAC by increasing the growth and motility of the pancreatic cancer cells, thereby worsening the prognosis of these patients. Therefore, ARHGEF15 could serve as a novel therapeutic target in patients with PDAC.

Hepatocyte nuclear factor 1 beta induces transformation and epithelial-to-mesenchymal transition

Gene amplification can be a cause of cancer, and driver oncogenes have been often identified in amplified regions. However, comprehensive analysis of other genes coamplified with an oncogene is rarely performed. We focused on the 17q12-21 amplicon, which contains ERBB2. We established a screening system for oncogenic activity with the NMuMG epithelial cell line. We identified a homeobox gene, HNF1B, as a novel cooperative transforming gene. HNF1B induced cancerous phenotypes, which were enhanced by the coexpression of ERBB2, and induced epithelial-to-mesenchymal transition and invasive phenotypes. These results suggest that HNF1B is a novel oncogene that can work cooperatively with ERBB2.

Clear cell neuroendocrine tumor of pancreas: Endoscopic Ultrasound-guided fine needle aspiration diagnosis of an uncommon variant

The cytomorphologic features of clear cell neuroendocrine tumor of pancreas have been rarely reported in cytology literature. The cytomorphology of this rare variant mimics many primary and metastatic clear cell tumors of the pancreas. However, a precise cytological diagnosis can be rendered by awareness of this entity and judicious use of immunohistochemistry. We report one such case in a young woman diagnosed on endoscopic ultrasound fine needle aspiration. The tumor cells showed positive staining with synaptophysin, chromogranin, and also with inhibin.

Expression, Epigenetic and Genetic Changes of HNF1B in Endometrial Lesions

Hepatocyte nuclear factor 1-beta (HNF-1-beta) is a transcription factor involved in cancerogenesis of various tumors, including endometrioid carcinoma. We performed comprehensive analysis of HNF-1-beta in lesions of the endometrium, including protein expression and genetic and epigenetic changes. Expression of HNF-1-beta was analyzed immunohistochemically in 320 cases including both tumor and non-tumor endometrial lesions. Promoter methylation and genetic variants were evaluated, using bisulphite and direct sequencing, in 30 (18 fresh frozen, 12 FFPE tumors) endometrioid carcinomas (ECs) and 15 ovarian clear cell carcinomas (OCCCs) as a control group. We detected expression of HNF-1-beta in 28 % of ECs (51/180 cases), 26 % of serous carcinoma (7/27 cases), 83 % of endometrial clear cell carcinoma (15/18 cases), 93 % of hyperplastic polyps with atypias (13/14 cases), 100 % of hyperplastic polyps without atypias (16/16 cases), 88 % of hyperplasias with atypias (14/16 cases), 91 % of hyperplasias without atypias (10/11 cases), and in ≥80 % of different normal endometrium samples. The control group of OCCCs showed HNF-1-beta expression in 95 % (18/19 cases). Methylation in promoter region was detected in 13.3 % (4/30) of ECs, but not in corresponding normal tissue where available, nor in OCCCs (0/15 cases). Mutation analysis revealed truncating variant c.454C > T (p.Gln152X) in one EC and missense variant c.848C > T (p.Ala283Val) was detected in one OCCC. In conclusion, expression of HNF-1-beta was detected in various extents in all types of lesions analyzed, nevertheless its strong expression was mostly limited to clear cell carcinomas. Biological significance of genetic and epigenetic changes needs further investigation.

A review on hepatocyte nuclear factor-1beta and tumor

Hepatocyte nuclear factor-1beta (HNF1β) was initially identified as a liver-specific transcription factor. It is a homeobox transcription factor that functions as a homodimer or heterodimer with HNF1α. HNF1β plays an important role in organogenesis during embryonic stage, especially of the liver, kidney, and pancreas. Mutations in the HNF1β gene cause maturity-onset diabetes of the young type 5 (MODY5), renal cysts, genital malformations, and pancreas atrophy. Recently, it has been shown that the expression of HNF1β is associated with cancer risk in several tumors, including hepatocellular carcinoma, pancreatic carcinoma, renal cancer, ovarian cancer, endometrial cancer, and prostate cancer. HNF1β also regulates the expression of genes associated with stem/progenitor cells, which indicates that HNF1β may play an important role in stem cell regulation. In this review, we discuss some of the current developments about HNF1β and tumor, the relationship between HNF1β and stem/progenitor cells, and the potential pathogenesis of HNF1β in various tumors.

Immunohistochemical Comparison of Ovarian and Uterine Endometrioid Carcinoma, Endometrioid Carcinoma With Clear Cell Change, and Clear Cell Carcinoma

Accurate distinction of clear cell carcinoma (CCC) from endometrioid carcinoma (EC) has important clinical implications, but, not infrequently, EC demonstrates clear cell change (EC-CC), mimicking CCC. We examined whether a panel of immunomarkers can help distinguish between these tumors. Sixty-four CCCs (40 ovarian and 24 uterine), 34 ECs (21 ovarian and 13 uterine), and 34 EC-CCs (6 ovarian and 28 uterine) were stained for HNF1β, BAF250a, Napsin A, ER, and PR. Intensity and extent of immunoreactivity was assessed. Fifty-seven of 64 (89%) CCCs, 14/34 (41%) EC-CCs, and 16/34 (47%) ECs expressed HNF1β, and 56/64 (88%) CCCs, 4/34 (12%) EC-CCs, and 1/34 (3%) ECs stained for Napsin A. Most CCCs demonstrated at least moderate and diffuse staining for both markers, whereas only focal and weak expression was identified in most EC-CC/EC. Compared to HNF1β, Napsin A showed increased specificity (93.0% vs. 55.9%, P<0.0001) and similar sensitivity (87.5% vs. 89.1%) in distinguishing CCC from EC-CC/EC. Thirteen of 64 (20%) CCCs, 6/34 (18%) EC-CCs, and 2/34 (6%) ECs showed loss of BAF250a. ER was expressed by 10/64 (16%) CCCs, 30/34 (88%) EC-CCs, and 33/34 (97%) ECs, whereas PR positivity was identified in 9/64 (14%) CCCs, 26/34 (77%) EC-CCs, and 33/34 (97%) ECs. The majority of EC and EC-CC demonstrated diffuse staining for ER/PR, whereas most CCCs showed very focal positivity. There is a statistically significant difference in HNF1β, Napsin A, ER, and PR immunoexpression between CCC and EC/EC-CC, with Napsin A being a more specific marker for CCC than HNF1β. Overall, the immunoprofile of EC-CC is more comparable to that of EC than CCC. The use of a panel of immunostains can help distinguish EC-CC from CCC.

Overexpression Of Hepatocyte Nuclear Factor-1beta Predicting Poor Prognosis Is Associated With Biliary Phenotype In Patients With Hepatocellular Carcinoma

Hepatocyte nuclear factor-1beta (HNF-1B) is involved in the hepatobiliary specification of hepatoblasts to cholangiocytes during liver development, and is strongly expressed throughout adult biliary epithelium. The aim of this study was to examine the expression of HNF-1B in different pathologic subtypes of primary liver cancer, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (ICC), and the relationship between HNF-1B expression, clinicopathological features and prognosis. We retrospectively investigated 2 cohorts of patients, including 183 HCCs and 69 ICCs. The expression of HNF-1B was examined by immunohistochemistry. We found that HNF-1B expression was associated with pathological subtype of primary tumor, and HNF-1B expression in HCC tissue may be associated with the change of phenotype on recurrence. The HNF-1B expression was positively correlated with biliary/HPC (hepatic progenitor cell) markers expression. Further, multivariable analysis showed that HNF-1B expression was an independent prognostic factor for both overall survival and disease-free survival of HCC patients. However, no correlation between HNF-1B expression and survival was found in ICC patients. In summary, HCC with high HNF-1B expression displayed biliary phenotype and tended to show poorer prognosis. HNF-1B-positive malignant cells could be bipotential cells and give rise to both hepatocytic and cholangiocytic lineages during tumorigenesis.

Expression of HNF-1β in cervical carcinomas: an immunohistochemical study of 155 cases

Background

HNF-1β is a commonly used marker in the differential diagnosis of clear cell carcinoma of the ovary and endometrium. Recent studies have found HNF-1β expression to a lesser extent in other ovarian and endometrial tumors including endometrioid, mucinous and, rarely, serous carcinoma. Regarding cervical carcinoma, HNF-1β expression has been mentioned exceptionally in mesonephric and some other types of adenocarcinoma. However, a systematic analysis of HNF-1β expression in cervical carcinomas has not been performed to date.

Methods

We analyzed HNF-1β expression in 155 cervical carcinomas (including 56 adenocarcinomas, 85 squamous cell carcinomas and 14 undifferentiated carcinomas). Expression of HNF-1β was correlated with the expression of other markers including estrogen receptors, progesterone receptors, CEA, p63, p40, p16, and D2-40.

Results

Adenocarcinomas showed expression of HNF-1β in 42/56 cases (75%), CEA in 48/56 cases (85.7%), p63 in 4/56 cases (7.2%), p40 in 2/56 cases (3.6%), estrogen receptors in 9/56 cases (16.1%), progesterone receptors in 5/56 cases (8.9%), p16 in 56/56 (100%) cases, and D2-40 in 0/56 cases (0%). Squamous cell carcinomas showed expression of HNF-1β in 2/85 cases (2.35%), CEA in 77/85 cases (90.6%), p63 and p40 in 85/85 cases (100%), estrogen receptors in 9/85 cases (10.6%), progesterone receptors in 1/85 cases (1.2%), p16 in 84/85 cases (98.8%), and D2-40 in 45/84 cases (53.6%). Undifferentiated carcinomas showed expression of HNF-1β in 2/14 cases (14.3%), CEA in 8/14 cases (57.1%), p16 in 14/14 cases (100%), hormone receptors in 0/13 cases (0%), p63 in 7/14 cases (50%), p40 in 5/14 cases (35.7%), and D2-40 in 1/14 cases (7.1%).

Conclusions

In cervical carcinoma, expression of HNF-1β is mostly restricted to adenocarcinomas and can be used as an auxiliary adenocarcinoma marker in the differential diagnosis of poorly differentiated cervical carcinomas. HNF-1β as an adenocarcinoma marker and p63/p40 and D2-40 as a squamous cell carcinoma markers are highly specific with variable sensitivity. Optimal results can be achieved using these markers in a panel.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1348836442160205.

HNF-1β in ovarian carcinomas with serous and clear cell change

Many ovarian tumors, including high-grade serous carcinoma (HGSC), show clear cell change. Accurate diagnosis is important, however, as ovarian clear cell carcinoma (OCCC) is known to be less responsive to traditional types of ovarian cancer chemotherapies. In a previous study, the clinical, morphologic, and immunohistochemical features of 32 ovarian carcinomas, which had been previously diagnosed as pure OCCC (n=11), pure HGSC (n=11), and mixed serous and clear cell (MSC) (n=10), were analyzed. The immunoreactivities of WT1, ER, and p53, as well as the mitotic indices and stages of presentation of the MSC, were similar to those of HGSC. It was consequently concluded that MSC represented HGSC with clear cell change. Hepatocyte nuclear factor-1β (HNF-1β) is a relatively new immunohistochemical marker that has been shown to be rather sensitive and specific for OCCC. We thus sought to evaluate this marker in this specific group of tumors. One block each of pure HGSC and pure OCCC were stained with HNF-1β. In the cases of MSC, 2 blocks were stained when the serous and clear cell components were not present on the same slide. None (0/11) of the pure HGSC showed immunoreactivity for HNF-1β, whereas all (11/11) of the pure OCCC were positive. In the cases of MSC, both the serous and clear cell components were negative for HNF-1β. HNF-1β seems to be a sensitive and specific marker for OCCC and is not expressed in HGSC with clear cell change. The pattern of immunoreactivity of HNF-1β in tumors with both serous and clear cell change supports the conclusion that MSC are HGSC with clear cells.

Genome-wide association study identifies a common variant associated with risk of endometrial cancer

Endometrial cancer is the most common malignancy of the female genital tract in developed countries. To identify genetic variants associated with endometrial cancer risk, we performed a genome-wide association study involving 1,265 individuals with endometrial cancer (cases) from Australia and the UK and 5,190 controls from the Wellcome Trust Case Control Consortium. We compared genotype frequencies in cases and controls for 519,655 SNPs. Forty seven SNPs that showed evidence of association with endometrial cancer in stage 1 were genotyped in 3,957 additional cases and 6,886 controls. We identified an endometrial cancer susceptibility locus close to HNF1B at 17q12 (rs4430796, P = 7.1 × 10(-10)) that is also associated with risk of prostate cancer and is inversely associated with risk of type 2 diabetes.

The use of immunohistochemistry in the diagnosis of metastatic clear cell renal cell carcinoma: a review of PAX-8, PAX-2, hKIM-1, RCCma, and CD10

The diagnosis of metastatic clear cell renal cell carcinoma may be difficult in some cases, particularly in the small image-guided biopsies that are becoming more common. As targeted therapies for renal cell carcinoma are now standard treatment, the recognition and diagnosis of renal cell carcinoma has become even more critical. Many adjunctive immunohistochemical markers of renal epithelial lineage such as CD10 and RCCma have been proposed as aids in the diagnosis of metastatic renal cell carcinoma, but low specificities often limit their utility. More recently described markers (PAX-2, PAX-8, human kidney injury molecule-1, hepatocyte nuclear factor-1-β, and carbonic anhydrase-IX) offer the potential for greater sensitivity and specificity in this diagnostic setting; however, knowledge of their expected staining in other neoplasms and tissues is critical for appropriate use. In this review, we discuss the most widely used immunohistochemical markers of renal lineage with an emphasis on their sensitivity and specificity for metastatic clear cell renal cell carcinoma. Subsequently, we present a variety of organ-specific differential diagnostic scenarios in which metastatic clear cell renal cell carcinoma might be considered and we propose immunopanels for use in each situation.

Clear cell carcinoma of the pancreas--a case report and review of the literature

Most of the malignant neoplasms of the pancreas demonstrate features that are consistent with adenocarcinoma. According to the WHO classification, primary clear cell carcinoma of the pancreas is rare and it is classified as a "miscellaneous" carcinoma. In addition, there is not an adequate systematic overview that can demonstrate its true existence as a definable entity. We report here on an unusual case of primary pancreatic clear cell carcinoma, which is the first such reported case in Korea. A 66 year old woman presented with abdominal pain and significant weight loss over the previous three weeks. On the abdominal computed tomography (CT), we detected an abdominal mass involving the pancreas tail and liver, and clear cell carcinoma with rhabdoid feature was seen on the histologic evaluation. The tumor cells showed well defined cell membranes, clear cytoplasm and prominent cell boundaries. The immunohistochemical stains showed positive reactions to antibodies against pan-cytokeratin, cytokeratin 7, carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA). On the other hand, there was a negative reaction for cytokeratin 20, chromogranin, synaptophysin, smooth muscle actin and HMB-45. She was diagnosed with a primary pancreatic clear cell carcinoma with hepatic metastasis and she received palliative gemcitabine chemotherapy. The patient died one month later of pancreatic cancer progression.