Utility of a CEA, CD15, Calretinin, and CK5/6 Panel for Distinguishing Between Mesotheliomas and Pulmonary Adenocarcinomas in Clinical Practice

GFPT2: A novel biomarker in mesothelioma for diagnosis and prognosis and its molecular mechanism in malignant progression

BACKGROUND

Mesothelioma (MESO) is an insidious malignancy with a complex diagnosis and a poor prognosis. Our study unveils Glutamine-Fructose-6-Phosphate Transaminase 2 (GFPT2) as a valuable diagnostic and prognostic marker for MESO, exploring its role in MESO pathogenesis.

METHODS

We utilised tissue samples and clinicopathologic data to evaluate the diagnostic and prognostic significance of GFPT2 as a biomarker for MESO. The role of GFPT2 in the malignant progression of MESO was investigated through in vitro and in vivo experiments. The activation of NF-κB-p65 through O-GlcNAcylation at Ser75 was elucidated using experiments like HPLC-QTRAP-MS/MS and mass spectrometry analysis.

RESULTS

The study demonstrates that GFPT2 exhibits a sensitivity of 92.60% in diagnosing MESO. Overexpression of it has been linked to an unfavourable prognosis. Through rigorous verification, we have confirmed that elevated GFPT2 levels drive malignant proliferation, invasiveness, and metastasis in MESO. At the molecular level, GFPT2 augments p65 O-GlcNAcylation, orchestrating its nuclear translocation and activating the NF-κB signalling pathway.

CONCLUSIONS

Our insights suggest GFPT2's potential as a distinctive biomarker for MESO diagnosis and prognosis, and as an innovative therapeutic target, offering a new horizon for identification and treatment strategies in MESO management.

Utility of a Highly Specific and Sensitive Podoplanin/D2-40, Calretinin, Thyroid Transcription Factor-1, and Carcinoembryonic Antigen/CD66e Immunohistochemical Panel in Differentiating Malignant Pleural Mesothelioma from Metastatic Adenocarcinoma: An Egyptian Experience

Background and Objective

Considering plentiful immunohistochemical (IHC) antibodies, a selection of highly sensitive and specific targeted panels is necessary to differentiate malignant pleural mesothelioma (MPM) from metastatic adenocarcinoma. We aimed to examine the sensitivity and specificity of four markers (podoplanin [PDPN]/D2-40, calretinin, thyroid transcription factor-1 [TTF-1], and carcinoembryonic antigen [CEA]/CD66e) as an initial IHC panel of Egyptian patients with malignant pleural biopsies.

Materials and Methods

Forty Egyptian malignant pleural biopsies with histomorphological features of mesothelioma versus adenocarcinoma were immunohistochemically stained by PDPN/D2-40, calretinin, TTF-1, and CEA/CD66e.

Results

PDPN/D2-40 and calretinin were positive in 27/27, 100% of mesothelioma cases with 100% sensitivity, 96.4% specificity for PDPN/D2-40, and 100% sensitivity and specificity for calretinin. Membranous PDPN/D2-40 expression was strong in 14 cases (53.85%), moderate in eight cases (30.77%), and weak in four cases (15.38%), while pure cytoplasmic staining was reported in one case. Calretinin was predominantly nuclear in all mesothelioma cases. TTF1 and CEA/CD66e were negative in all mesothelioma cases. In adenocarcinomas, PDPN/D2-40 was only expressed as weak cytoplasmic staining in 1/13 cases, while calretinin was negative in all 13 cases. Nuclear TTF1 and cytoplasmic CEA/CD66e immunostaining positivity were reported in all adenocarcinoma cases (13/13) with 100% sensitivity and specificity for both markers.

Conclusion

The combination of PDPN/D2-40, calretinin together with CEA/CD66e, and TTF1 may be highly valuable in differentiating MPM from metastatic adenocarcinoma.

Application of immunohistochemistry in diagnosis and management of malignant mesothelioma

Immunohistochemistry plays an indispensable role in accurate diagnosis of malignant mesothelioma, particularly in morphologically challenging cases and in biopsy and cytology specimens, where tumor architecture is difficult or impossible to evaluate. Application of a targeted panel of mesothelial- and epithelial-specific markers permits correct identification of tumor lineage in the vast majority of cases. An immunopanel including two mesothelial markers (calretinin, CK5/6, WT-1, or D2-40) and two epithelial markers (MOC-31 and claudin-4) offers good sensitivity and specificity, with adjustments as appropriate for the differential diagnosis. Once mesothelial lineage is established, malignancy-specific studies can help verify a diagnosis of malignant mesothelioma. BAP1 loss, CDKN2A homozygous deletion, and MTAP loss are highly specific markers of malignancy in a mesothelial lesion, and they attain acceptable diagnostic sensitivity when applied as a diagnostic panel. Novel markers of malignancy, such as 5-hmC loss and increased EZH2 expression, are promising, but have not yet achieved widespread clinical adoption. Some diagnostic markers also have prognostic significance, and PD-L1 immunohistochemistry may predict tumor response to immunotherapy. Application and interpretation of these immnuomarkers should always be guided by clinical history, radiographic findings, and above all histomorphology.

Neutrophils and Snail Orchestrate the Establishment of a Pro-tumor Microenvironment in Lung Cancer

Understanding the immune compartment of tumors facilitates the development of revolutionary new therapies. We used a Kras(G12D)-driven mouse model of lung cancer to establish an immune signature and identified a contribution of Gr1⁺ neutrophils to disease progression. Depletion experiments showed that Gr1⁺ cells (1) favor tumor growth, (2) reduce T cell homing and prevent successful anti-PD1 immunotherapy, and (3) alter angiogenesis, leading to hypoxia and sustained Snail expression in lung cancer cells. In turn, Snail accelerated disease progression and increased intratumoral Cxcl2 secretion and neutrophil infiltration. Cxcl2 was produced mainly by neutrophils themselves in response to a factor secreted by Snail-expressing tumor cells. We therefore propose a vicious cycle encompassing neutrophils and Snail to maintain a deleterious tumor microenvironment.

Overexpressed genes in malignant pleural mesothelioma: implications in clinical management

Malignant pleural mesothelioma (MPM) is a very aggressive cancer poorly responsive to current therapies. MPM patients have a very poor prognosis with a median survival of less than one year from the onset of symptoms. The biomarkers proposed so far do not lead to a sufficiently early diagnosis for a radical treatment of the disease. Thus, the finding of novel diagnostic and prognostic biomarkers and therapeutic targets is needed. Gene overexpression has been frequently associated with a malignant phenotype in several cancer types; therefore the identification of overexpressed genes may lead to the detection of novel prognostic or diagnostic marker and to the development of novel therapeutic approaches, based on their inhibition. In the last years, several overexpressed genes have been identified in MPM through gene expression profiling techniques: among them it has been found a group of 51 genes that resulted overexpressed in more than one independent study, revealing their consistency among studies. This article reviews the clinical implications of confirmed overexpressed genes in MPM described so far in literature.

[Metastasis revealing malignant peritoneum mesothelioma: About the difficulty to identify the primary tumors]

Peritoneal malignant mesothelioma is a rare and extremely aggressive tumor that is sometimes difficult to diagnose. We report two cases of metastatic malignant peritoneal mesothelioma. In one case, malignant metastatic cells were identified in cervical lymph nodes while in the other case, the cells were found in the liver. In both cases, metastases were identified before discovering the primary tumor. This led to the misdiagnosis of carcinoma of unknown origin. Nevertheless, the histological and immuno-histochemical patterns were typical of malignant mesothelioma. Regarding metastasis of unknown origin, a differentiation of epithelioid peritoneal malignant mesothelioma and adenocarcinoma proved to be difficult. Therefore, we discuss the diagnostic usefulness of immuno-histochemical mesothelioma markers.

Expression and diagnostic values of calretinin and CK5/6 in cholangiocarcinoma

BACKGROUND

Mesothelin, a mesothelial marker, has been found expressed in and as a potential treatment target of cholangioacarcinoma (CC). It is possible that CC may be derived from the cells sharing mesothelial markers. However, the expression of other mesothelial markers in CC is largely unknown.

METHODS

Thirty CC cases (10 extrahepatic and 20 intrahepatic) were retrieved from our institutional archive. The immunohistochemical study of Calretinin (DC8), WT1 (6F-H2), Lymphatic Endothelial Marker (D2-40), CK5/6 (D5/16 B4) and CK19 (b170) was done on formalin fixed paraffin embedded sections for 2-3 blocks of each case. We compared the expression levels between CC and normal bile duct (NBD) on the same block.

RESULTS

All of the CC and NBD are positive for CK19 (23/23) and negative for WT1 (0/23) and D2-40 (0/23), except one CC positive for D2-40(1/30, 3.3%) and one NBD positive for WT1 (1/23, 4.3%). Calretinin immunoreactivity was detected in 52.2% (12/23) of CC, but none in NBD (0/23). CK5/6 was also detectable in 73.3% (22/30) of CC and all NBD (30/30). Increased expression of calretinin and reduced expression of CK5/6 were more likely associated with CC than NBD (P < 0.001 and P = 0.002, respectively). The sequential staining pattern of positive calretinin and negative CK5/6 in calretinin negative cases has a sensitivity of 69.57% and a specificity of 100% for differentiating CC from NBD. CK5/6 expression was also more likely associated with well-differentiated CC (7/7 versus 12/20 in moderately differentiated, and 9/10 in poorly differentiated, P = 0.019) and extrahepatic CC (10/10 versus 12/20 in intrahepatic, P = 0.029), but there was no association between the calretinin expression and the CC grade or location.

CONCLUSION

Calretinin and CK5/6 immunohistochemical stains may be useful for diagnosing a CC. Their immunohistochemical results should be interpreted with caution in the cases with differential diagnoses of mesothelioma and CC. A full mesothelioma panel, including WT1 and/or D2-40, is recommended to better define a mesothelial lineage. The biology of calretinin and CK5/6 expression in CC is unclear, but might shed light on identifying therapeutic targets for CC.

Relative influence of c-Kit expression and epidermal growth factor receptor gene amplification on survival in patients with non-small cell lung cancer

c-Kit and epidermal growth factor receptor (EGFR) have critical roles in cell proliferation and differentiation in patients with non-small cell lung cancer (NSCLC). The present study aimed to investigate the prognostic impact of c-Kit and/or EGFR expression in tumor tissue samples from 146 patients with NSCLC. c-Kit expression was analyzed using immunohistochemistry and the expression of EGFR was assessed using fluorescence in situ hybridization. Univariate and multivariate analyses identified that c-Kit is a significant negative prognostic factor. The expression of c-Kit was correlated with poor differentiation, pleura involvement and smoking history (P=0.043, 0.007 and 0.032, respectively). Furthermore, patients with c-Kit-positive expression were associated with a significantly lower overall survival compared with those exhibiting c-Kit-negative expression (P=0.048). The median follow-up time was 19 months post-surgery. EGFR gene amplification as a result of polysomy of chromosome 7 was found to be negatively correlated with poor differentiation and smoking history (P=0.023 and 0.044, respectively). The findings of the present study indicate that c-Kit and EGFR expression is a strong, independent, negative prognostic factor in NSCLC.

Malignant mesothelioma of the pericardium: a report of two different presentations

Malignant mesothelioma of the pericardium is a rare and fatal condition that clinicians should be aware of due to its variability of clinical manifestation. The diagnosis may be delayed as a result of delayed treatment. Here, we report two cases of malignant pericardial mesothelioma with two different clinical aspects: cardiac tamponade and mimic tuberculous pericarditis. Both patients: may have indirect exposure to asbestos. Despite chemotherapy, both patients died at 2 weeks and 3 months after the diagnosis. Malignant mesothelioma of the pericardium is fatal, has a variety of presentation, and may not be related to asbestosis exposure.