Specific expression patterns of epithelial to mesenchymal transition factors in gestational molar disease

Pathogenic role of Twist-1 protein in hydatidiform molar pregnancies and investigation of its potential diagnostic utility in complete moles

BACKGROUND

Complete and partial moles (PM) are the most common gestational trophoblastic diseases. Due to some overlapping morphological findings, ancillary studies may be necessary.

METHODS

In this cross-sectional study, 47 cases of complete mole (CM) and 40 cases of PM were randomly selected based on histopathological criteria. Only those cases that were agreed upon by two expert gynecological pathologists and confirmed by the P57 IHC study were included. The expression level of the Twist-1 marker in villi stromal cells, as well as syncytiotrophoblasts, was evaluated quantitatively (percentage of positive cells), qualitatively (staining intensity) and as a total comprehensive score.

RESULTS

Expression of Twist-1 is higher and more intense in villous stromal cells of CMs (p < 0.001). Moderate to strong staining intensity in more than 50% of villous stromal cells, can differentiate CM and PM with 89.5% sensitivity and 75% specificity. In syncytiotrophoblasts of CM, Twist-1 expression was significantly lower than PM (p < 0.001). Negative or weak staining intensity in less than 10% of syncytiotrophoblasts, can distinguish CM and PM with 82.9% sensitivity and 60% specificity.

CONCLUSION

A higher expression of Twist-1 in villous stromal cells of hydatidiform moles is a sensitive and specific marker for the diagnosis of CMs. An elevated expression of this marker in villous stromal cells suggests another pathogenic mechanism for more aggressiveness of CMs in addition to the characteristics of trophoblast cells. The opposite result was obtained in the expression of Twist-1 in the syncytiotrophoblasts, compatible with defects in the process of formation of these supportive cells in CMs.

Challenges in diagnosing hydatidiform moles: a review of promising molecular biomarkers

INTRODUCTION

Hydatidiform moles (HMs) are pathologic conceptions with unique genetic bases and abnormal placental villous tissue. Overlapping ultrasonographical and histological manifestations of molar and non-molar (NM) gestations and HMs subtypes makes accurate diagnosis challenging. Currently, immunohistochemical analysis of p57 and molecular genotyping have greatly improved the diagnostic accuracy.

AREAS COVERED

The differential expression of molecular biomarkers may be valuable for distinguishing among the subtypes of HMs and their mimics. Thus, biomarkers may be the key to refining HMs diagnosis. In this review, we summarize the current challenges in diagnosing HMs, and provide a critical overview of the recent literature about potential diagnostic biomarkers and their subclassifications. An online search on PubMed, Web of Science, and Google Scholar databases was conducted from the inception to 1 April 2022.

EXPERT OPINION

the emerging biomarkers offer new possibilities to refine the diagnosis for HMs and pregnancy loss. Although the additional studies are required to be quantified and investigated in clinical trials to verify their diagnostic utility. It is important to explore, validate, and facilitate the wide adoption of newly developed biomarkers in the coming years.

CD117 Is a Specific Marker of Intraductal Papillary Mucinous Neoplasms (IPMN) of the Pancreas, Oncocytic Subtype

The intraductal oncocytic papillary neoplasm (IOPN) of the pancreas has been recognized by WHO classification as a unique intraductal papillary mucinous neoplasm (IPMN) category. IOPN is composed of oxyphil cells, usually expressing MUC5AC, MUC6, and Hep Par-1, and harboring PRKACA/B fusion genes as their genetic hallmark. Although IOPNs are associated with an infiltrative adenocarcinoma in up to 30% of cases, the survival rate after surgical resection approaches 100%. This highlights the importance of the correct IOPN diagnosis, above all in cases with an associated invasive component. In this study, the immunohistochemical expression of CD117 was investigated in 111 IPMNs, including 17 oncocytic, 45 gastric, 20 pancreatico-biliary, and 29 intestinal IPMNs. We also tested the expression of MUC5AC, MUC6, and Hep Par-1 in the IOPN cohort. CD117 positivity was significantly more frequent in IOPNs compared to the other IPMN subtypes (p < 0.0001). Furthermore, within IOPN, a lower or absent CD117, MUC5AC, MUC6, and Hep Par-1 expression tended to be associated with the presence of an infiltrative component. Our findings shed light into the biology of these complex lesions, which are confirmed to be a distinctive IPMN subtype; notably, CD117 emerged as a potential, additional tool in the differential diagnosis of IPMNs.

Epithelial-mesenchymal transition in undifferentiated carcinoma of the pancreas with and without osteoclast-like giant cells

Undifferentiated carcinoma (UC) and undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) are peculiar variants of pancreatic ductal adenocarcinoma (PDAC), characterized by hypercellularity and absence of glandular patterns. The inflammatory microenvironment is peculiar in UCOGC, since it is dominated by macrophages and osteoclast-like giant cells. However, from a molecular point of view, both UC and UCOGC are very similar to conventional PDAC, sharing alterations of the most common genetic drivers. Clinically, UC usually show a worse prognosis, whereas UCOGC may show a better prognosis if it is not associated with a PDAC component. To highlight potential biological differences between these entities, we investigated the role of the epithelial to mesenchymal transition (EMT) in UC and UCOGC. Specifically, we analyzed the immunohistochemical expression of three well-known EMT markers, namely Twist1, Snai2, and E-cadherin, in 16 cases of UCOGC and 10 cases of UC. We found that EMT is more frequently activated in UC (10/10 cases) than in UCOGC (8/16 cases; p = 0.05). Furthermore, in UCOGC, EMT was activated with a higher frequency in cases with an associated PDAC component. Snai2 was the most frequently and strongly expressed marker in both tumor types (10/10 UC, 8/16 UCOGC), and its expression was higher in UC than in UCOGC (mean immunohistochemical score: 4.8 in UC vs. 2.1 in UCOGC, p < 0.01). Our results shed new light on the biology of UC and UCOGC: EMT appeared as a more important process in UC, and Snai2 emerged as a central EMT effector in this setting.

The Activation Status of the TGF-β Transducer Smad2 Is Associated with a Reduced Survival in Gastrointestinal Cancers: A Systematic Review and Meta-Analysis

Aberrant function of Smad2, a crucial member of transforming growth factor beta (TGF-β) signaling, is associated with the development of malignancies, particularly in the gastrointestinal district. However, little is known about its possible prognostic role in such tumor types. With the first meta-analysis on this topic, we demonstrated that the lack of the activated form of Smad2 (phosphor-Smad2 or pSmad2), which was meant to be the C-terminally phosphorylated form, showed a statistically significant association with an increased risk of all-cause mortality in patients with gastrointestinal cancers (RR, 1.58; 95% CI, 1.05–2.37, p = 0.029, I² = 84%), also after having adjusted for potential confounders (RR, 1.65; 95% CI, 1.24–2.18; p < 0.001; I² = 4%). This finding highlights the importance of the TGF-β signaling in this type of cancer. In this line, further studies are needed to explore more in depth this important molecular pathway, focusing also on potential therapeutic strategies based on its effectors or molecular targets.

A case report of three synchronous tumors in the same pancreatic specimen

It is known that Duodenal adenocarcinoma (DA) is a rare malignant solid tumor that cause occlusion symptoms with orthodox dysphagia when locally advanced. Pancreatic neuroendocrine tumors (PanNETs) account for about 2% of all pancreatic neoplasms. The combination of these two lesions, with the synchronous presence of ectopic pancreatic tissue (EPT) of the duodenum, has never been described in literature, to our knowledge. Here we report a case of combined DA, EPT and PanNET affecting a 71-year-old woman.

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Simultaneous presence of Duodenal adenocarcinoma pancreatic neuroendocrine tumor ectopic pancreatic tissue of duodenum.

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Biochemical tests did not reveal abnormalities: CA 19-9 was normal, CEA was 153 U/L.

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Ultrasonography confirmed a nodule dislocating pancreas investigated with contrast-enhanced CT and esophagogastroduodenoscopy.

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The association between duodenal adenocarcinomas, PanNET and ectopic pancreatic tissue (EPT) of the duodenum is really rare.

Gestational trophoblastic neoplasms (GTNs) do not display epithelial-to-mesenchymal transition (EMT) features

Although epithelial-to-mesenchymal transition (EMT) has been described in the development of complete hydatidiform moles and the invasion of the maternal decidua by trophoblasts during normal human placentation, its implication in gestational trophoblastic neoplasm (GTN) without villi is totally unknown. We studied the immunoexpression of EMT transcription factors (TWIST1, ZEB1, ZEB2), E-cadherin, and vimentin in 18 trophoblastic tumors and pseudo-tumors. Weak nuclear TWIST1 immunostaining was seen in 5% to 10% of all trophoblastic cells, without ZEB1 and ZEB2 nuclear staining. Trophoblastic cells did not express vimentin, and the expression of E-cadherin was maintained in all cases, indicating the absence of EMT features in GTN.

Prognostic Role of High-Grade Tumor Budding in Pancreatic Ductal Adenocarcinoma: A Systematic Review and Meta-Analysis with a Focus on Epithelial to Mesenchymal Transition

This study aims at clarifying the prognostic role of high-grade tumor budding (TB) in pancreatic ductal adenocarcinoma (PDAC) with the first systematic review and meta-analysis on this topic. Furthermore, we analyzed with a systematic review the relationship between TB and a recently suggested TB-associated mechanism: the epithelial to mesenchymal transition (EMT). Analyzing a total of 613 patients, 251 of them (40.9%) with high grade-TB, we found an increased risk of all-cause mortality (RR, 1.46; 95% CI, 1.13–1.88, p = 0.004; HR, 2.65; 95% CI, 1.79–3.91; p < 0.0001) and of recurrence (RR, 1.61; 95% CI, 1.05–2.47, p = 0.03) for PDAC patients with high-grade TB. Moreover, we found that EMT is a central process in determining the presence of TB in PDAC. Thanks to this meta-analysis, we demonstrate the potential clinical significance of high-grade TB for prognostic stratification of PDAC. TB also shows a clear association with the process of EMT. Based on the results of the present study, TB should be conveyed in pathology reports and taken into account by future oncologic staging systems.

PD-1, PD-L1, and CD163 in pancreatic undifferentiated carcinoma with osteoclast-like giant cells: expression patterns and clinical implications

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGC), a variant of pancreatic ductal adenocarcinoma (PDAC), has a striking genetic similarity to PDAC but a significantly improved overall survival. We hypothesize that this difference could be due to the immune response to the tumor, and as such, we investigated the expression of PD-1, PD-L1, and CD163 in a series of UCOGC. To this aim, 27 pancreatic UCOGCs (11 pure and 16 PDAC-associated), 5 extrapancreatic tumors with osteoclast-like giant cells and 10 pancreatic anaplastic carcinomas were immunostained using antibodies against PD-1, PD-L1, and CD163. In pancreatic UCOGCs, PD-L1 was expressed in neoplastic cells of 17 (63%) of 27 cases, more often in cases with an associated PDAC (P = .04). Expression of PD-L1 was associated with poor prognosis, confirmed by multivariate analysis: patients with PD-L1-positive UCOGCs had a risk of all-cause mortality that was 3 times higher than did patients with PD-L1-negative UCOGCs (hazard ratio, 3.397; 95% confidence interval, 1.023-18.375; P = .034). PD-L1 expression on tumor cells was also associated with aberrant P53 expression (P = .035). PD-1 was expressed on rare lymphocytes in 12 UCOGCs (44.4%), mainly located at the tumor periphery. CD163 was expressed on histiocytes, with a diffuse and strong staining pattern in all UCOGCs. Extrapancreatic tumors with osteoclast-like giant cells showed very similar staining patterns for the same proteins. Anaplastic carcinomas have some similarities to UCOGCs, but PD-L1 has no prognostic roles. Our results may have important implications for immunotherapeutic strategies in UCOGCs; these tumors may also represent a model for future therapeutic approaches against PDAC.

Diagnostic Utility of Twist1, Ki-67, and E-Cadherin in Diagnosing Molar Gestations and Hydropic Abortions

OBJECTIVES

This study aims to assess whether the expression of Twist1, Ki-67, and E-cadherin can guide the differential diagnosis of complete hydatidiform mole (CHM), partial hydatidiform mole (PHM), and hydropic abortion (HA).

METHODS

Differential expression of Twist1, Ki-67, and E-cadherin was analyzed in gestational products from 55 cases of CHM, PHM, and HA using immunohistochemistry. Prior to analysis, the studied cases were confirmed for their diagnosis by flow cytometric assessment of DNA ploidy and p57 immunostaining.

RESULTS

Twist1 expression can distinguish CHM from PHM and HA with 100% sensitivity, 100%, specificity, 100% positive predictive value (PPV), and 100% negative predictive value (NPV). Furthermore, combined Ki-67 and E-cadherin expression could differentiate PHM and HA with 100% sensitivity, 93.3% specificity, 92.3% PPV, and 100% NPV.

CONCLUSIONS

Twist1 expression is a highly reliable marker for the diagnosis of CHM, where combined Ki-67 and E-cadherin immunoreactivity can distinguish PHM from nonmolar pregnancies.

Assessing the quality of studies in meta-analyses: Advantages and limitations of the Newcastle Ottawa Scale

One of the most important points in the meta-analyses is certainly represented by the assessment of the quality of the studies included in such research. The meta-analyses are considered the highest level of evidence in science. Also for this reason, the quality of the studies included should be accurately evaluated by standardized tools. The overall results of the meta-analysis depend indeed also on a rigorous evaluation of the studies quality. Among all the possible tools for this complex evaluation, the Newcastle Ottawa Scale (NOS) is one of the most used worldwide, above all for observational studies. In this review, we will discuss the strengths and limitation of the NOS, also on the basis of the branch of science in which it has been applied.

Fhit down-regulation is an early event in pancreatic carcinogenesis

Aberrant Fhit expression characterizes a large proportion of primary pancreatic ductal adenocarcinomas (PDACs), but fragmentary information is available on Fhit expression during the phenotypic changes of pancreatic ductal epithelium during multistep transformation. We assessed Fhit expression by immunohistochemistry in two different multistep pancreatic carcinogenic processes: pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasia (IPMN). We considered 105 surgically treated PDACs/IPMNs and selected 30 samples of non-neoplastic pancreatic parenchyma, 50 PanIN lesions, 30 IPMNs, 15 IPMNs with associated invasive carcinoma, and 60 adenocarcinomas. Normal pancreatic ducts and surrounding acinar cells consistently showed moderate to strong Fhit immunoreactivity. Significant down-regulation of Fhit expression was observed in association with increasing severity of dysplastia/neoplastia in both carcinogenic processes. This was further confirmed by studying multiple lesions obtained from the same surgical specimen. Of 60 PDACs, only 14 showed Fhit expression comparable to normal pancreatic ductal epithelium, while the remainder (77%) showed clearly negative or reduced Fhit expression. This study demonstrates that Fhit down-regulation is an early event in both multistep carcinogenic processes leading to PDAC.

Pulmonary adenocarcinoma with enteric differentiation: Dissecting oncogenic genes alterations with DNA sequencing and FISH analysis

BACKGROUND

Pulmonary Adenocarcinoma with Enteric Differentiation (PAED) is a rare subtype of adenocarcinoma of emerging interest, recently introduced in the 2015 WHO classification. However, little is known about major molecular signatures of this class of adenocarcinomas and information about new biomarkers totally lack.

METHODS

We examined the NRAS, PIK3CA, EGFR, KRAS and BRAF status through mass spectrometry sequencing and ALK rearrangement by FISH in a series of 8 PAEDs.

RESULTS

1/8 (12.5%) case had a simultaneous PIK3CA mutation (E545K) and an EML4-ALK translocation. KRAS gene showed a mutation in the codon 12 in 4/8 of PAED (50%), NRAS, BRAF and EGFR genes were wild type in all tumor samples.

CONCLUSIONS

We concluded that PIK3CA mutations and ALK rearrangement occur also in PAEDs, while NRAS mutations might be a very rare event similarly to pulmonary adenocarcinomas of conventional type. KRAS is the prevailing gene mutated in this class of adenocarcinoma.

A rare case of three different tumors in the same pancreatic specimen: a case report and brief review of the literature

Solid pseudopapillary tumors (SPT) of the pancreas are rare neoplasms mainly affecting young women. Pancreatic serous cystadenomas (SCAs) and pancreatic neuroendocrine tumors (PanNETs) account for about 2% of all pancreatic neoplasms. The combination of these three lesions, to our knowledge, has never been described in literature. Here we report a case of combined SPT, SCA and PanNET affecting a 33-year-old woman.

Epithelial-mesenchymal transition during extravillous trophoblast differentiation

A successful pregnancy depends on the intricate and timely interactions of maternal and fetal cells. Placental extravillous cytotrophoblast invasion involves a cellular transition from an epithelial to mesenchymal phenotype. Villous cytotrophoblasts undergo a partial epithelial to mesenchymal transition (EMT) when differentiating into extravillous cytotrophoblasts and gain the capacity to migrate and invade. This review summarizes our current knowledge regarding known regulators of EMT in the human placenta, including the inducers of EMT, upstream transcription factors that control EMT and the downstream effectors, cell adhesion molecules and their differential expression and functions in pregnancy pathologies, preeclampsia (PE) and fetal growth restriction (FGR). The review also describes the research strategies that were used for the identification of the functional role of EMT targets in vitro. A better understanding of molecular pathways driven by placental EMT and further elucidation of signaling pathways underlying the developmental programs may offer novel strategies of targeted therapy for improving feto-placental growth in placental pathologies including PE and FGR.

RASSF1 tumor suppressor gene in pancreatic ductal adenocarcinoma: correlation of expression, chromosomal status and epigenetic changes

Background

The Ras Association Domain Family Member 1 (RASSF1) is one of the most frequently reported methylation-inactivated tumor suppressor genes in primary pancreatic ductal adenocarcinomas (PDAC). Limited information is still available about the impact of RASSF1 gene silencing on the expression of its different isoforms in neoplastic cells.

Methods

A series of 96 primary PDAC, with known clinico-pathological parameters, was tested for RASSF1 methylation status by methylation-specific PCR, RASSF1 locus copy number alterations by fluorescence in situ hybridization, and Rassf1a protein expression by immunohistochemistry. A further series of 14 xenografted primary PDAC and 8 PDAC-derived cell lines were tested to obtain a detailed methylation mapping of CpG islands A and C of the RASSF1 locus by pyrosequencing and to evaluate the expression of Rassf1 variants by qRT-PCR.

Results

Methylation of CpG island A of the RASSF1 gene was observed in 35 % of the tumors and allelic loss of RASSF1 locus was seen in 30 disomic and in 20 polysomic cases (52 %). Rassf1a immunohistochemical expression was downregulated in half of primary PDAC, and this downregulation was neither correlated with methylation of RASSF1 promoter nor with RASSF1 copy number alterations. RASSF1 status did not influence patients’ prognosis. The expression of the seven RASSF1 isoforms in xenografts and cell lines showed that RASSF1A, RASSF1B, and RASSF1C isoforms were present in all xenografts and cell lines, whereas RASSF1D, RASSF1E, and RASSF1F isoforms were variably expressed among samples. RASSF1G was never expressed in either xenografts or cell lines. The variable expression of RASSF1 isoforms in PDAC xenografts and cell lines was not dependent on RASSF1 methylation status of CpG islands A and C.

Conclusions

RASSF1 alterations occurring in PDAC mainly consist in variations of expression of the different isoforms. Different genetic mechanisms seem to contribute to RASSF1 deregulation in this setting, but RASSF1 methylation does not seem to substantially affect RASSF1 isoforms expression.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2048-0) contains supplementary material, which is available to authorized users.