Aspartic proteinase napsin is a useful marker for diagnosis of primary lung adenocarcinoma

Proteogenomic characterization reveals tumorigenesis and progression of lung cancer manifested as subsolid nodules

Lung adenocarcinoma (LUAD) radiologically displayed as subsolid nodules (SSNs) is prevalent. Nevertheless, the precise clinical management of SSNs necessitates a profound understanding of their tumorigenesis and progression. Here, we analyze 66 LUAD displayed as SSNs covering 3 histological stages including adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC) by incorporating genomics, proteomics, phosphoproteomics and glycoproteomics. Intriguingly, cholesterol metabolism is aberrantly regulated in the preneoplastic AIS stage. Importantly, target ablation of proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes the initiation of LUAD. Furthermore, sustained endoplasmic reticulum stress is demonstrated to be a hallmark and a reliable biomarker of AIS progression to IAC. Consistently, target promotion of ER stress profoundly retards LUAD progression. Our study provides comprehensive proteogenomic landscape of SSNs, sheds lights on the tumorigenesis and progression of SSNs and suggests preventive and therapeutic strategies for LUAD.

Canine lung carcinoma-A descriptive review

Primary lung cancer is a relatively uncommon tumor in dogs, accounting for about 1% of all canine malignancies. Clinical signs in affected dogs can range from being asymptomatic to exhibiting chronic cough, and in rare cases, dyspnoea. Surgical excision of the primary tumor, along with resection of the affected locoregional lymph nodes is the preferred treatment option for most cases. Although chemotherapy, targeted therapy and radiation therapy have been employed, their effectiveness remain controversial. Dogs with stage T1 tumors can experience extended survival times of up to 2 years. However, the prognosis for dogs with advanced metastatic tumors is generally very poor. This review article discusses the etiology, clinical signs, diagnosis, staging, treatment options, and prognosis of primary lung carcinoma in dogs.

Case report: Isolated oligometastatic disease of the prostate from a primary lung adenocarcinoma

Secondary prostate cancer typically occurs from direct seeding of a renal or bladder tumor. Metastasis via hematogenous spread is exceedingly rare and is typically identified incidentally at autopsy. This report describes a 72-year-old male with lung adenocarcinoma initially staged as Stage IA2 who developed oligometastatic disease of the prostate. He was initially treated with radiation therapy and was found to have a hypermetabolic focus in the prostate gland during surveillance PET/CT imaging 6 months following treatment. Subsequent biopsy revealed metastatic lung adenocarcinoma in 6/6 core samples, leading to diagnosis of oligometastatic disease of the prostate. To our knowledge, this is the first report of isolated oligometastatic disease to the prostate from a primary lung adenocarcinoma.

Histological and immunohistochemical features of carcinomas with pulmonary involvement in cattle

Primary pulmonary neoplasms in cattle are rare. There are few studies on the pathological findings of these neoplasms in this species. This study aimed to describe the histological and immunohistochemical findings of primary and metastatic pulmonary carcinomas in cattle. We conducted a retrospective study of 19 cases of epithelial neoplasms with pulmonary involvement. Histologically, most of the neoplasms were classified as primary pulmonary neoplasms, including different adenocarcinoma subtypes (4/19, 21%) and adenosquamous carcinomas (3/19, 16%), followed by squamous cell carcinoma (6/19, 32%), metastatic uterine adenocarcinoma (4/19, 21%), metastatic hepatocellular carcinoma (1/19, 5%), and metastatic cholangiocarcinoma (1/19, 5%). By immunohistochemistry, all neoplasms were positive for pancytokeratin, and 4/19 (21%) were positive for vimentin. Primary pulmonary neoplasms had immunoreactivity for thyroid transcription factor-1 (6/7), while only 2 of these cases were positive for napsin A. All cases with squamous differentiation (9/9) had immunoreactivity for cytokeratin (CK) 5/6, while only 7 of these cases were positive for p40. CK20, CK7, and CK8/18 showed varied immunoreactivity in the primary and metastatic pulmonary carcinomas but were important markers to confirm the diagnosis of primary mucinous adenocarcinoma and metastatic cholangiocarcinoma. HepPar-1 was only positive in the metastatic hepatocellular carcinoma. The limited number of cases of metastatic uterine adenocarcinomas in this study precluded identification of a specific immunophenotype for this tumor. Immunohistochemistry proved to be an important tool to confirm the proper classification of these neoplasms.

The role of adenocarcinoma subtypes and immunohistochemistry in predicting lymph node metastasis in early invasive lung adenocarcinoma

BACKGROUND

Identifying lymph node metastasis areas during surgery for early invasive lung adenocarcinoma remains challenging. The aim of this study was to develop a nomogram mathematical model before the end of surgery for predicting lymph node metastasis in patients with early invasive lung adenocarcinoma.

METHODS

In this study, we included patients with invasive lung adenocarcinoma measuring ≤ 2 cm who underwent pulmonary resection with definite pathology at Qilu Hospital of Shandong University from January 2020 to January 2022. Preoperative biomarker results, clinical features, and computed tomography characteristics were collected. The enrolled patients were randomized into a training cohort and a validation cohort in a 7:3 ratio. The training cohort was used to construct the predictive model, while the validation cohort was used to test the model independently. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors. The prediction model and nomogram were established based on the independent risk factors. Recipient operating characteristic (ROC) curves were used to assess the discrimination ability of the model. Calibration capability was assessed using the Hosmer-Lemeshow test and calibration curves. The clinical utility of the nomogram was assessed using decision curve analysis (DCA).

RESULTS

The overall incidence of lymph node metastasis was 13.23% (61/461). Six indicators were finally determined to be independently associated with lymph node metastasis. These six indicators were: age (P < 0.001), serum amyloid (SA) (P = 0.008); carcinoma antigen 125 (CA125) (P = 0. 042); mucus composition (P = 0.003); novel aspartic proteinase of the pepsin family A (Napsin A) (P = 0.007); and cytokeratin 5/6 (CK5/6) (P = 0.042). The area under the ROC curve (AUC) was 0.843 (95% CI: 0.779-0.908) in the training cohort and 0.838 (95% CI: 0.748-0.927) in the validation cohort. the P-value of the Hosmer-Lemeshow test was 0.0613 in the training cohort and 0.8628 in the validation cohort. the bias of the training cohort corrected C-index was 0.8444 and the bias-corrected C-index for the validation cohort was 0.8375. demonstrating that the prediction model has good discriminative power and good calibration.

CONCLUSIONS

The column line graphs created showed excellent discrimination and calibration to predict lymph node status in patients with ≤ 2 cm invasive lung adenocarcinoma. In addition, the predictive model has predictive potential before the end of surgery and can inform clinical decision making.

Machine learning for pan-cancer classification based on RNA sequencing data

Despite recent improvements in cancer diagnostics, 2%-5% of all malignancies are still cancers of unknown primary (CUP), for which the tissue-of-origin (TOO) cannot be determined at the time of presentation. Since the primary site of cancer leads to the choice of optimal treatment, CUP patients pose a significant clinical challenge with limited treatment options. Data produced by large-scale cancer genomics initiatives, which aim to determine the genomic, epigenomic, and transcriptomic characteristics of a large number of individual patients of multiple cancer types, have led to the introduction of various methods that use machine learning to predict the TOO of cancer patients. In this review, we assess the reproducibility, interpretability, and robustness of results obtained by 20 recent studies that utilize different machine learning methods for TOO prediction based on RNA sequencing data, including their reported performance on independent data sets and identification of important features. Our review investigates the strengths and weaknesses of different methods, checks the correspondence of their results, and identifies potential issues with datasets used for model training and testing, assessing their potential usefulness in a clinical setting and suggesting future improvements.

Deciphering Lung Adenocarcinoma Heterogeneity: An Overview of Pathological and Clinical Features of Rare Subtypes

Lung cancer is one of the most frequently diagnosed cancers worldwide and the leading cause of cancer-related death. The 2021 World Health Organization (WHO) classification provided a detailed and updated categorization of lung adenocarcinomas with a special focus on rare histological types, including enteric, fetal and colloid types, as well as not otherwise specified adenocarcinoma, overall accounting for about 5-10% of all cases. However, rare entities are nowadays difficult to diagnose in most centers, and evidence of optimal therapeutic management for these patients is still lacking. In recent years, increasing knowledge about the mutational profile of lung cancer, in addition to the spreading diffusion of next-generation sequencing (NGS) in different centers, have been helpful in the identification of rare variants of lung cancer. Hence, the hope is that several new drugs will be available in the near future to treat these rare lung tumors, such as in targeted therapy and immunotherapy, which are often used in clinical practice for several malignancies. The aim of this review is to summarize the current knowledge about the molecular pathology and clinical management of the most common rare adenocarcinoma subtypes in order to provide a concise and updated report that can drive clinicians' choices in their routine practice.

Urinary detection of lung cancer in mice via noninvasive pulmonary protease profiling

Lung cancer is the leading cause of cancer-related death, and patients most commonly present with incurable advanced-stage disease. U.S. national guidelines recommend screening for high-risk patients with low-dose computed tomography, but this approach has limitations including high false-positive rates. Activity-based nanosensors can detect dysregulated proteases in vivo and release a reporter to provide a urinary readout of disease activity. Here, we demonstrate the translational potential of activity-based nanosensors for lung cancer by coupling nanosensor multiplexing with intrapulmonary delivery and machine learning to detect localized disease in two immunocompetent genetically engineered mouse models. The design of our multiplexed panel of sensors was informed by comparative transcriptomic analysis of human and mouse lung adenocarcinoma datasets and in vitro cleavage assays with recombinant candidate proteases. Intrapulmonary administration of the nanosensors to a Kras- and Trp53-mutant lung adenocarcinoma mouse model confirmed the role of metalloproteases in lung cancer and enabled accurate detection of localized disease, with 100% specificity and 81% sensitivity. Furthermore, this approach generalized to an alternative autochthonous model of lung adenocarcinoma, where it detected cancer with 100% specificity and 95% sensitivity and was not confounded by lipopolysaccharide-driven lung inflammation. These results encourage the clinical development of activity-based nanosensors for the detection of lung cancer.

Pulmonary enteric adenocarcinoma

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Synthetically expounded the clinical characteristics of PEAC.

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Systematically described the differentiation of PEAC from primary lung adenocarcinoma and MCRC.

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Found patients with PEAC may have high frequencies of HER2 and MMR mutations.

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Proposed a new conjecture that patients with PEAC might benefit from anti-HER2 therapy and immune checkpoint inhibitors.

Pulmonary enteric adenocarcinoma (PEAC) is an exceptionally rare subtype of non–small cell lung cancer (NSCLC). It is characterized by pathological features similar to those of colorectal adenocarcinoma. Most patients with PEAC have almost no special clinical manifestations, and it is often difficult to differentiate from metastatic colorectal adenocarcinoma (MCRC). As a special type of lung adenocarcinoma, PEAC has unique mutation expression and immune characteristics; its mutation profile shows higher Kirsten rat sarcoma viral oncogene (KRAS), human epidermal growth factor receptor-2 (HER2) , DNA mismatch repair(MMR) mutation rates, and much lower epidermal growth factor receptor (EGFR) rate. So in the future, targeted therapy may tend to be a new light in the treatment of PEAC. As for immunohistochemistry (IHC), CDX-2, villin, and CK7 are significantly positive in PEAC. This review focuses on the pathologic features, immunohistochemical examination, mutation analysis, diagnosis, treatment, and prognosis of PEAC.

Napsin A Expression in Human Tumors and Normal Tissues

Background: Novel aspartic proteinase of the pepsin family A (Napsin A, TAO1/TAO2) is a functional aspartic proteinase which is involved in the maturation of prosurfactant protein B in type II pneumocytes and the lysosomal protein catabolism in renal cells. Napsin A is highly expressed in adenocarcinomas of the lung and is thus commonly used to affirm this diagnosis. However, studies have shown that other tumors can also express Napsin A.

Methods: To comprehensively determine Napsin A expression in normal and tumor tissue, 11,957 samples from 115 different tumor types and subtypes as well as 500 samples of 76 different normal tissue types were evaluable by immunohistochemistry on tissue microarrays.

Results: Napsin A expression was present in 16 different tumor types. Adenocarcinoma of the lung (85.6%), clear cell adenocarcinoma of the ovary (71.7%), clear cell adenocarcinoma of the endometrium (42.8%), papillary renal cell carcinoma (40.2%), clear cell (tubulo) papillary renal cell carcinoma (16.7%), endometrial serous carcinoma (9.3%), papillary thyroid carcinoma (9.3%) and clear cell renal cell carcinoma (8.2%) were among the tumors with the highest prevalence of Napsin A positivity. In papillary and clear cell renal cell carcinoma, reduced Napsin A expression was linked to adverse clinic-pathological features (p ≤ 0.03).

Conclusion: This methodical approach enabled us to identify a ranking order of tumors according to their relative prevalence of Napsin A expression. The data also show that loss of Napsin A is linked to tumor dedifferentiation in renal cell carcinomas.

A study on the immunohistochemical expression of napsin A in oral squamous cell carcinomas, intraepithelial neoplasia, and normal oral mucosa

Napsin A is an aspartic proteinase expressed in some types of carcinomas, such as lung adenocarcinomas and renal cell carcinomas but rarely in squamous cell carcinomas. No specific studies have been carried out focusing on napsin A antibody expression in oral squamous cell carcinomas (OSCC). The aim of this study was to investigate the reactivity of this antibody in primary OSCC. This retrospective study included 70 OSCC cases of which 31 (44.3%) presented metastasis involvement. Patient data, including age, gender, tumor location, histological grade, regional and distant metastasis, were collected. OSCC edge epithelium with intraepithelial neoplasia and healthy oral mucosa (n = 10) were included in the analysis. Sections of lung adenocarcinomas (n = 2) were used as the positive control and an immunohistochemical assay for napsin A was performed on all cases. Napsin A expression was negative in all 70 cases of OSCC, as well as in the intraepithelial neoplasia adjacent to the carcinoma area and in healthy oral mucosa epithelium. Metastatic neck lymph nodes and distant organs were also negative for napsin A. This study shows that napsin A is consistently not expressed in oral squamous cell carcinoma, or in metastatic sites of primary OSCC, intraepithelial neoplasia, and healthy oral mucosa.

Exploiting proteases for cancer theranostic through molecular imaging and drug delivery

The measurement of biological processes at a molecular and cellular level serves as a basis for molecular imaging. As compared with traditional imaging approaches, molecular imaging functions to probe molecular anomalies that are the basis of a disease rather than the evaluation of end results of these molecular changes. Proteases play central role in tumor invasion, angiogenesis and metastasis thus can be exploited as a target for imaging probes in early diagnosis and treatment of tumors. Molecular imaging of protease has undergone tremendous breakthroughs in the field of diagnosis. It allows the clinicians not only to see the tumor location but also provides an insight into the expression and activity of different types of markers associated with the tumor microenvironment. These imaging techniques are expected to have a huge impact on early cancer detection and personalized cancer treatment. Effective development of protease imaging probes with the highest in vivo biocompatibility, stability and most appropriate pharmacokinetics for clinical translation will upsurge the success level of early cancer detection and treatment.

Immunohistochemical expression of Napsin A in normal human fetal lungs at different gestational ages and in acquired and congenital pathological pulmonary conditions

Surfactant protein B (SP-B) is a key component of pulmonary surfactant. SP-B is processed to a mature, surface-active protein from a pro-peptide by two distinct cleavage events in its N-terminal and C-terminal regions. Napsin A, a protease expressed in type II pneumocytes, is responsible for the N-terminal cleavage event. Here, for the first time, we have evaluated the expression of Napsin A in normal fetal lungs at different gestational ages and in lungs from fetuses and neonates with congenital and acquired pathological pulmonary conditions. Lung samples were collected from fetal and neonatal autopsies at the Department of Medicine and Surgery's Pathology Unit of Parma University (Italy). Immunohistochemical analysis was performed using a primary anti-Napsin A (clone IP64 clone) monoclonal antibody. A section of lung adenocarcinoma was used as an external positive control. Napsin A was expressed early in normal fetal lungs throughout the epithelium of the distal pseudoglandular tracts. In fetuses at 30 weeks of gestation and term newborns, Napsin A was already expressed only in isolated cells within the alveolar epithelium, similar to adult subjects. Furthermore, increased expression of Napsin A compared with a control group was observed in lung tissue from fetuses and a newborn with pathological conditions (inflammatory diseases and pulmonary hypoplasia). In conclusion, this study demonstrates that Napsin A is produced early in fetal life, and that its production is increased in many diseases, presumably in an effort to remedy functional pulmonary failure.

TGF‑β1 induces CREB1‑mediated miR‑1290 upregulation to antagonize lung fibrosis via Napsin A

The pathologic mechanisms of pulmonary fibrosis (PF), one of the most common chronic pulmonary diseases, remain unclear. Napsin A is an aspartic proteinase that has been regarded as a hallmark of pulmonary adenocarcinoma. The present study aimed to investigate the specific function and molecular mechanisms of Napsin A in PF from the perspective of microRNA (miRNA or miR) regulation. In the present study, it was found that miR-1290 downregulated the expression of Napsin A by binding to its 3′-UTR. Cell viability was examined by MTT assay. The protein levels of α-smooth muscle actin (α-SMA), Collagen I and Napsin A were examined by western blot analysis. The predicted targeting of Napsin A by miR-1290 was validated by luciferase reporter assay. The protein content of α-SMA was examined by immunofluorescence staining. miR-1290 was found to be upregulated in blood samples from patients with PF and in TGF-β1-stimulated A549 cells. miR-1290 was found to directly target Napsin A. miR-1290 overexpression also significantly promoted A549 cell proliferation and increased the protein levels of markers of fibrosis. Napsin A knockdown exerted effects on A549 cell proliferation and TGF-β1-induced fibrosis that were similar to those induced by miR-1290 overexpression; more importantly, Napsin A knockdown significantly reversed the effects of miR-1290 inhibition, indicating that miR-1290 promotes TGF-β1-induced fibrosis by targeting Napsin A. Moreover, TGF-β1-induced CAMP responsive element binding protein 1 (CREB1) overexpression promoted the transcription of miR-1290 in A549 cells. On the whole, the findings of the present study demonstrate that TGF-β1-induced CREB1 over-expression induces the significant upregulation of miR-1290 expression, thus aggravating TGF-β1-induced fibrotic changes in A549 cells via the miR-1290 downstream target, Napsin A.

Napsin A Expression in Subtypes of Thyroid Tumors: Comparison with Lung Adenocarcinomas

Napsin A is widely used in the diagnosis of lung adenocarcinoma and has also been reported to be positive in cases of thyroid carcinomas. We investigated napsin A levels through immunohistochemistry on whole sections of 210 primary thyroid tumors of various subtypes and another 41 metastatic thyroid carcinomas, and compared these with 125 primary and 25 metastatic lung adenocarcinomas. The results showed that napsin A was expressed in 23.8% thyroid tumors and 30.3% papillary thyroid carcinomas. Most cases showed a focal and weak to moderate expression. In comparison, 80.8% primary lung adenocarcinomas expressed napsin A, with mostly diffused and strong expression. For metastatic carcinomas of thyroid and lung origin, napsin A was detected in 39.0% of thyroid carcinomas in contrast to 88.0% in cases of lung adenocarcinomas. Comparisons of additional markers, TTF-1, CK7, thyroglobulin, and Pax-8 in metastatic carcinomas showed the overlapping expression of immunomarkers of TTF-1 and CK7. Thyroglobulin and Pax-8 were useful for distinguishing between metastatic carcinomas; however, Pax-8 may be a superior marker due to its higher sensitivity. The clinicopathological analysis of papillary thyroid carcinomas showed that the expression of napsin A was positively correlated with lymph node metastasis (p = 0.030). Here, we focused on the expression of napsin A in thyroid tumors and compared it with that in lung adenocarcinomas. The expression of napsin A is common in thyroid tumors and the combined expression of napsin A and TTF-1 in a metastatic thyroid carcinoma is a cause for concern due to chances of misdiagnosis as lung adenocarcinoma.

Best Practices Recommendations for Diagnostic Immunohistochemistry in Lung Cancer

Since the 2015 WHO classification was introduced into clinical practice, immunohistochemistry (IHC) has figured prominently in lung cancer diagnosis. In addition to distinction of small cell versus non-small cell carcinoma, patients' treatment of choice is directly linked to histologic subtypes of non-small cell carcinoma, which pertains to IHC results, particularly for poorly differentiated tumors. The use of IHC has improved diagnostic accuracy in the classification of lung carcinoma, but the interpretation of IHC results remains challenging in some instances. Also, pathologists must be aware of many interpretation pitfalls, and the use of IHC should be efficient to spare the tissue for molecular testing. The International Association for the Study of Lung Cancer Pathology Committee received questions on practical application and interpretation of IHC in lung cancer diagnosis. After discussions in several International Association for the Study of Lung Cancer Pathology Committee meetings, the issues and caveats were summarized in terms of 11 key questions covering common and important diagnostic situations in a daily clinical practice with some relevant challenging queries. The questions cover topics such as the best IHC markers for distinguishing NSCLC subtypes, differences in thyroid transcription factor 1 clones, and the utility of IHC in diagnosing uncommon subtypes of lung cancer and distinguishing primary from metastatic tumors. This article provides answers and explanations for the key questions about the use of IHC in diagnosis of lung carcinoma, representing viewpoints of experts in thoracic pathology that should assist the community in the appropriate use of IHC in diagnostic pathology.

Diagnostic Accuracy of Fine-Needle Aspiration Cytology for Discrimination of Squamous Cell Carcinoma from Adenocarcinoma in Non-Small Cell Lung Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

To determine the accuracy with which morphology alone can distinguish adenocarcinoma and squamous cell carcinoma in non-small cell lung cancer.

METHODS

We performed a systematic review and meta-analysis. Three data bases (MEDLINE, EMBASE, Scopus) were searched for studies on the diagnostic accuracy of subtyping non-small cell lung cancer. Accuracy data was abstracted and synthesized using bivariate mixed effects logistic regression as implemented in the midas package in Stata 14. Heterogeneity was assessed using the Higgins I2.

RESULTS

We included 17 studies (2,235 cases). Most studies had a low risk of bias. The pooled diagnostic accuracy for cytological diagnosis of adenocarcinoma resulted in a sensitivity of 63% (48-76%) and specificity of 95% (87-98%). The I2 values were 93 and 88% for sensitivity and specificity, respectively. The pooled diagnostic accuracy for the cytological diagnosis of squamous cell carcinoma resulted in a sensitivity of 84% (79-88%) and a specificity of 90% (84-94%). The I2 values were 69 and 86% for sensitivity and specificity, respectively.

CONCLUSION

Accuracy varies widely by study and summary estimates do not provide a useful representation of accuracy. Squamous cell carcinoma was diagnosed more accurately than adenocarcinoma.

Overexpression of Napsin A resensitizes drug-resistant lung cancer A549 cells to gefitinib by inhibiting EMT

Lung cancer is one of the most common malignant tumors and also the leading cause of cancer-related deaths in the world. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI), such as gefitinib, have been used in the therapy of lung cancer. However, the acquisition of drug resistance is a major limitation in the clinical efficiency of EGFR-TKIs. Epithelial-mesenchymal transition (EMT) has been demonstrated to be an underlying mechanism of acquired resistance. A previous study has reported that Napsin A expression can inhibit EMT in lung cancer cells. The present study therefore investigated the effect of Napsin A on the sensitivity of EGFR-TKI-resistant lung cancer cells. First, a drug-resistant lung cancer cell line was generated using the EGFR-TKI gefitinib on A549 cells (termed here A549-GFT). EMT was demonstrated to be induced in the drug resistant A549-GFT cells, evidenced by reduced E-cadherin expression and increased Vimentin expression compared with control A549 cells. Next, Napsin A was overexpressed in the cells by transfection of the Napsin A-expression vector, PLJM1-Napsin A. Western blot analysis confirmed that the protein expression levels of Napsin A were significantly elevated in the Napsin A-overexpressing cells. Cell proliferation and apoptosis assays were performed to evaluate the effect of Napsin A overexpression on resistant A549 cells. The results of MTT assay demonstrated that Napsin A overexpression inhibited the proliferation of A549 and drug-resistant A549-GFT cells and that the proliferation of Napsin A-overexpressing A549-GFT cells was significantly inhibited by gefitinib treatment compared with control A549-GFT cells. The results from the Annexin V/propidium iodide double staining apoptosis assay indicated that Napsin A overexpression enhanced gefitinib-induced apoptosis in A549-GFT cells. Additionally, EMT was reversed following Napsin A expression in A549-GFT cells, as evidenced by the restoration of E-cadherin and downregulation of Vimentin expression. Further investigation demonstrated that Napsin A overexpression resulted in inhibition of focal adhesion kinase, a critical factor in integrin signaling, in the resistant A549-GFT cells. These data suggested that Napsin A resensitized the drug-resistant A549-GFT cells to gefitinib, possibly by reversing EMT via integrin signaling inhibition. Therefore, Napsin A combined with a TKI may be a more effective treatment strategy for lung cancer.

Napsin A is negatively associated with EMT‑mediated EGFR‑TKI resistance in lung cancer cells

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR‑TKI) have been used as a standard therapy for patients with lung cancer with EGFR‑activating mutations. Epithelial‑mesenchymal transition (EMT) has been reported to be associated with the development of EGFR‑TKI resistance, which limits the clinical efficacy of EGFR‑TKI. Therefore, investigating the resistance‑associated mechanism is required in order to elucidate an effective therapeutic approach to enhance the sensitivity of lung cancer to EGFR‑TKI. In the present study, EGFR‑TKI erlotinib‑sensitive H358, H322 and H441 lung cancer cells, erlotinib‑moderately sensitive A549 cells, and erlotinib‑insensitive HCC827 cells with EGFR‑mutation (exon 19 deletion) were used to detect the mRNA and protein expression of the EMT‑associated proteins E‑cadherin and vimentin, and napsin A, by reverse transcription‑quantitative polymerase chain reaction analysis and western blotting. It was observed that the E‑cadherin expression level in erlotinib‑sensitive cells was increased compared with the moderately sensitive A549 cells and HCC827 cells; however, vimentin exhibited opposite expression, suggesting a correlation between EMT and erlotinib sensitivity in lung cancer cells. The napsin A expression level was observed to be positively associated with erlotinib sensitivity. In addition, napsin A highly‑expressingH322 cells were used and napsin A‑silenced cells were constructed using small interfering RNA (siRNA) technology, and were induced by transforming growth factor (TGF)‑βl. It was observed that TGF‑βl partially induced the alterations in E‑cadherin and vimentin expression and the occurrence of EMT in napsin A highly‑expressing cells, while TGF‑βl significantly induced EMT via downregulation of E‑cadherin and upregulation of vimentin in napsin A‑silenced cells; cell proliferation and apoptosis assays demonstrated that TGF‑βl induced marked resistance to erlotinib in napsin A‑silenced cells compared with napsin A‑expression cells. These data indicated that napsin A expression may inhibit TGF‑βl‑induced EMT and was negatively associated with EMT‑mediated erlotinib resistance, suggesting that napsin A expression may improve the sensitivity of lung cancer cells to EGFR‑TKI through the inhibition of EMT.

Clear cell carcinomas of the ovary and kidney: clarity through genomics

Clear cell ovarian carcinoma (CCOC) and clear cell renal cell carcinoma (ccRCC) both feature clear cytoplasm, owing to the accumulation of cytoplasmic glycogen. Genomic studies have demonstrated several mutational similarities between these two diseases, including frequent alterations in the chromatin remodelling SWI-SNF and cellular proliferation phosphoinositide 3-kinase-mammalian target of rapamycin pathways, as well as a shared hypoxia-like mRNA expression signature. Although many targeted treatment options have been approved for advanced-stage ccRCC, CCOC patients are still treated with conventional platinum and taxane chemotherapy, to which they are resistant. To determine the extent of similarity between these malignancies, we performed unsupervised clustering of mRNA expression data from these cancers. This review highlights the similarities and differences between these two clear cell carcinomas to facilitate knowledge translation within future research efforts. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Napsin A levels in epithelial lining fluid as a diagnostic biomarker of primary lung adenocarcinoma

BACKGROUND

It is crucial to develop novel diagnostic approaches for determining if peripheral lung nodules are malignant, as such nodules are frequently detected due to the increased use of chest computed tomography scans. To this end, we evaluated levels of napsin A in epithelial lining fluid (ELF), since napsin A has been reported to be an immunohistochemical biomarker for histological diagnosis of primary lung adenocarcinoma.

METHODS

In consecutive patients with indeterminate peripheral lung nodules, ELF samples were obtained using a bronchoscopic microsampling (BMS) technique. The levels of napsin A and carcinoembryonic antigen (CEA) in ELF at the nodule site were compared with those at the contralateral site. A final diagnosis of primary lung adenocarcinoma was established by surgical resection.

RESULTS

We performed BMS in 43 consecutive patients. Among patients with primary lung adenocarcinoma, the napsin A levels in ELF at the nodule site were markedly higher than those at the contralateral site, while there were no significant differences in CEA levels. Furthermore, in 18 patients who were undiagnosed by bronchoscopy and finally diagnosed by surgery, the napsin A levels in ELF at the nodule site were identically significantly higher than those at the contralateral site. In patients with non-adenocarcinoma, there were no differences in napsin A levels in ELF. The area under the receiver operator characteristic curve for identifying primary lung adenocarcinoma was 0.840 for napsin A and 0.542 for CEA.

CONCLUSION

Evaluation of napsin A levels in ELF may be useful for distinguishing primary lung adenocarcinoma.

A case of napsin A-positive metastatic lung cancer originating from the colon

BACKGROUND

We report a case of napsin A-positive metastatic lung cancer originating from the colon. No cases of napsin A-positive metastatic lung tumors originating from colorectal cancer have been reported previously.

CASE PRESENTATION

Computed tomography identified a small lung nodule in a 70-year-old male patient, 18 months after resection for rectal cancer. The size of the lung tumor increased from 1.8 to 2.1 cm in 6 months and metastasis from the rectal cancer was suspected. Resection of the lung tumor was performed, and the histological features of the lung tumor revealed findings typical of colorectal adenocarcinoma and resembled those of the original rectal cancer. Furthermore, the metastasis stained positive for napsin A and thyroid transcription factor-1 (TTF-1) on immunohistochemical evaluation, and immunohistochemical analysis identified the same results in the rectal specimen.

CONCLUSIONS

These findings led us to believe that this was a rare case of napsin A-positive metastatic lung cancer originating in the colon. The patient was treated with chemotherapy for recurrent rectal cancer, and no other metastases were found after the lung resection. This is the first report of napsin A-positive colorectal cancer metastasizing to the lung.

Surfactant Protein A and Napsin A in the Immunohistochemical Characterization of Canine Pulmonary Carcinomas: Comparison With Thyroid Transcription Factor-1

Thyroid transcription factor-1 (TTF-1) is a specific and sensitive marker for canine pulmonary tumors but is also expressed in thyroid carcinomas, which commonly metastasize to lung. Napsin A and surfactant protein A (SP-A) are used in the histologic diagnosis of non-small-cell lung cancer in humans but have not been thoroughly evaluated in neoplasms of dogs. The objective of this study was to compare the efficacy of immunohistochemistry for SP-A, napsin A, and TTF-1 in the diagnosis of canine pulmonary carcinomas. TTF-1, napsin A, and SP-A antibodies were applied to 67 formalin-fixed, paraffin-embedded canine pulmonary tumors. Although each marker had good sensitivity, only 3% (2/67) of lung tumors were negative for SP-A compared with 7% (5/67) and 9% (6/67) for napsin A and TTF-1, respectively. Each antigen was detected in a greater percentage of cells of tumors with acinar or papillary patterns compared with those with squamous differentiation. SP-A immunoreactivity was absent in all 113 nonpulmonary tumors tested. Of 108 normal tissues, SP-A was detected only in lung and in 1 of 6 adrenal, 1 of 3 endometrial, and 1 of 4 hepatic sections. Based on these findings, SP-A and napsin A are useful markers of canine lung epithelial neoplasia. Of these, SP-A is the most sensitive and specific (a possible pitfall is the need to distinguish entrapped normal pulmonary epithelial cells or alveolar macrophages from neoplastic cells) and can be used in combination with TTF-1 or napsin A to improve detection and differentiation of pulmonary carcinomas from metastatic tumors in the canine lung.

New immunohistochemical markers in the differential diagnosisof nonsmall cell lung carcinoma

BACKGROUND/AIM

The aim of this study was to investigate Napsin-A, NTRK-1, NTRK-2, Desmoglein-3, and Desmocollin-3 in the differential diagnosis and prognosis of nonsmall cell lung cancer.

MATERIALS AND METHODS

The expression of Napsin-A, NTRK-1, NTRK-2, and Desmoglein-3 was examined by immunohistochemistry in 50 squamous cell carcinomas and 50 adenocarcinomas. Desmocollin-3 was investigated in 29 squamous cell carcinoma and 29 adenocarcinoma cases. Associations between expression profiles of Napsin-A, NTRK-1, NTRK-2, Desmoglein-3, and Desmocollin-3 in lung cancers and clinicopathological variables were analyzed.

RESULTS

Napsin-A staining was statistically significant in detecting adenocarcinomas versus squamous cell carcinomas. The sensitivity of Napsin-A for adenocarcinomas was 96% and the specificity was 100%. NTRK-2 and Desmocollin-3 staining were statistically significant in detecting squamous cell carcinomas versus adenocarcinomas. Desmoglein-3, Napsin-A, and NTRK-2 had no effect on survival. Disease-free survival time was significantly shorter in cases that were moderately positive with NTRK-1.

CONCLUSION

Our data suggest that Napsin-A, NTRK-2, and Desmocollin-3 are useful markers in the differentiation of nonsmall cell lung cancer.

Utilization of ancillary studies in the cytologic diagnosis of respiratory lesions: The papanicolaou society of cytopathology consensus recommendations for respiratory cytology

The Papanicolaou Society of Cytopathology has developed a set of guidelines for respiratory cytology including indications for sputum examination, bronchial washings and brushings, CT-guided FNA and endobronchial ultrasound guided fine needle aspiration (EBUS-FNA), as well as recommendations for classification and criteria, ancillary testing and post-cytologic diagnosis management and follow-up. All recommendation documents are based on the expertise of committee members, an extensive literature review, and feedback from presentations at national and international conferences. The guideline documents selectively present the results of these discussions. The present document summarizes recommendations for ancillary testing of cytologic samples. Ancillary testing including microbiologic, immunocytochemical, flow cytometric, and molecular testing, including next-generation sequencing are discussed. Diagn. Cytopathol. 2016;44:1000-1009. © 2016 Wiley Periodicals, Inc.

Identification of prostate cancer biomarkers in urinary exosomes

Exosomes have recently appeared as a novel source of non-invasive cancer biomarkers since tumour-specific molecules can be found in exosomes isolated from biological fluids. We have here investigated the proteome of urinary exosomes by using mass spectrometry to identify proteins differentially expressed in prostate cancer patients compared to healthy male controls. In total, 15 control and 16 prostate cancer samples of urinary exosomes were analyzed. Importantly, 246 proteins were differentially expressed in the two groups. The majority of these proteins (221) were up-regulated in exosomes from prostate cancer patients. These proteins were analyzed according to specific criteria to create a focus list that contained 37 proteins. At 100% specificity, 17 of these proteins displayed individual sensitivities above 60%. Even though several of these proteins showed high sensitivity and specificity for prostate cancer as individual biomarkers, combining them in a multi-panel test has the potential for full differentiation of prostate cancer from non-disease controls. The highest sensitivity, 94%, was observed for transmembrane protein 256 (TM256; chromosome 17 open reading frame 61). LAMTOR proteins were also distinctly enriched with very high specificity for patient samples. TM256 and LAMTOR1 could be used to augment the sensitivity to 100%. Other prominent proteins were V-type proton ATPase 16 kDa proteolipid subunit (VATL), adipogenesis regulatory factor (ADIRF), and several Rab-class members and proteasomal proteins. In conclusion, this study clearly shows the potential of using urinary exosomes in the diagnosis and clinical management of prostate cancer.

Napsin A/p40 antibody cocktail for subtyping non-small cell lung carcinoma on cytology and small biopsy specimens

BACKGROUND

Subtyping non-small cell lung carcinomas (NSCLC) into adenocarcinoma (ACA) or squamous cell carcinoma (SQCC) is important for treatment and specimen triage for molecular studies. To preserve tissue for molecular studies in cytology/small biopsy specimens, a 2-antibody cocktail for NSCLC subtyping was developed.

METHODS

Markers for lung ACA (thyroid transcription factor 1 and napsin A) and SQCC (cytokeratin 5/6 and p40) were evaluated on tissue microarrays (TMAs) with 143 ACA and 98 SQCC specimens. The napsin A/p40 combination was selected for NSCLC subtyping and validated on the TMA as well as on a cohort of cell block/small biopsy specimens from 80 poorly differentiated NSCLCs.

RESULTS

Using TMA analysis, the napsin A-positive (+)/p40± immunophenotype identified ACA with 94% sensitivity and 100% specificity, whereas the napsin A (negative)-/p40+ immunophenotype identified SQCC with 100% sensitivity and specificity. On the validation cohort of 80 cell block and small biopsy specimens, the napsin A/p40 cocktail accurately subtyped 63 of 70 NSCLC (90%) as ACA or SQCC using the subsequent surgical resection as reference histology. Of the remaining 17 cases, 15 were classified as NSCLC-not otherwise specified based on a napsin A-/p40- immunophenotype; their corresponding resections were diagnosed as ACA (7 cases), large cell carcinoma (7 cases), or pleomorphic carcinoma (1 case). Two additional large cell carcinoma cases showed a napsin A-/p40+ or napsin A+/p40+ profile in the preoperative cell block/small biopsy sample.

CONCLUSIONS

A napsin A/p40 cocktail can accurately subtype NSCLC into ACA and SQCC in most cell block/small biopsy specimens of poorly differentiated NSCLC. In the minority of cases in which the napsin A/p40 immunophenotype is indeterminate, additional stains may be necessary for precise classification. Cancer Cytopathol 2016;124:472-84. © 2016 American Cancer Society.

Increased expressions of claudin 4 and 7 in atypical adenomatous hyperplasia and adenocarcinoma of the lung

Abnormal expression of claudin (Cldn), the main constituent of tight junctions, may play a crucial role in carcinogenesis. To elucidate these abnormalities of tight junctions in lung adenocarcinoma during carcinogenesis, we examined immunohistochemical expressions of Cldn4 and Cldn7 in human lung resection materials. Lung resection specimens from 86 patients were studied, including 16 atypical adenomatous hyperplasia (AAH), 19 adenocarcinoma in situ (AIS), 32 invasive adenocarcinoma (ADC), 5 AIS with AAH, 2 ADC with AAH, 10 ADC with AIS, and 2 ADC with AIS and AAH. The immunohistochemical staining (IHC) score was defined for both the extent and intensity of staining. IHC score for Cldn4 in AIS and ADC was significantly higher than that in alveolar epithelium (AE) and AAH (p < 0.001 for both). In addition, the AAH score was significantly higher than that in AE (p < 0.001). The Cldn7 score in ADC was significantly increased compared with AE and AAH (p < 0.001 for both). These results suggested that increase of Cldn4-expression may be involved in early molecular events during carcinogenesis of adenocarcinoma, whereas increase of Cldn7-expression may be associated with tumor invasion or progression.

Aberrant Expression of Napsin A in Breast Carcinoma With Apocrine Features

An incidental finding of napsin A-positive breast carcinoma with apocrine features during workup for metastatic cancer in an axillary lymph node led to our investigation of the incidence of napsin A expression in breast carcinomas, focusing on those with apocrine features. We included 97 cases of breast carcinomas and performed immunohistochemistry with napsin A, GATA-3, thyroid transcription factor-1, and GCDFP-15. There was a statistically significant difference between apocrine and nonapocrine cases with respect to polyclonal napsin A H-scores (P < .00152), monoclonal napsin A H-scores (P < .00631), GATA-3 H-scores (P < .00029), and GCDFP-15 H-scores (P < .00251). Of the 49 cases of apocrine carcinoma, monoclonal napsin A antibody was positive in 66.7% of cases, including in 7 (14.6%) that showed 3+ staining. The majority of nonapocrine cases were negative (62.5%) or weakly (1+) positive (29.2%), with none exhibiting 3+ strength. It is important for pathologists to be aware that breast carcinomas with apocrine features can express napsin A.

The role of Napsin-A and Desmocollin-3 in classifying poorly differentiating non-small cell lung carcinoma

There is increased need for classification of non-small cell lung cancer (NSCLC) into its major subtypes, adenocarcinoma (AC) and squamous cell carcinoma (SCC). Such a classification is enabled in poorly differentiated tumours based on routine morphology due to overlapping morphologic features. In such cases, the use of immunohistochemistry (IHC) can differentiate between the two subtypes.

PURPOSE

To test the ability of the two markers; Napsin-A and Desmocollin-3, in differentiating poorly differentiated (AC) from poorly differentiated SCC in small biopsies.

PATIENTS AND METHODS

This is a retrospective study including 60 patients who presented with pulmonary nodules. Cases with biopsy specimens diagnosed as poorly differentiated non-small cell lung cancer, and had corresponding resection specimens were included. Cell blocks were stained with anti Napsin-A, and anti Desmocollin-3. Cytoplasmic immunoreactivity for both markers was considered specific. Sensitivity, specificity, positive and negative predictive values, total accuracy and combined accuracy of both markers were calculated.

RESULTS

Napsin A showed a sensitivity of 89.3%, a specificity of 96.9%, PPV of 96.2%, NPV of 91.2%, and a total accuracy of 93.3% for AC, while Desmocollin-3 achieved 90.6% sensitivity, 96.4% specificity, 96.7% PPV, 90% NPV, and 93.3% total accuracy. Both markers achieved a total accuracy of 90%.

CONCLUSION

Napsin-A, and Desmocollin-3 were sensitive and specific markers for the diagnosis of AC and SCC, respectively. Both markers allowed classification of 54/60 cases into either AC or SCC.

Expressions of Thyroid Transcription Factor-1, Napsin A, p40, p63, CK5/6 and Desmocollin-3 in Non-Small Cell Lung Cancer, as Revealed by Imprint Cytology Using a Malinol-Based Cell-Transfer Technique

BACKGROUND

The introduction of new therapies has made it important to differentiate between adenocarcinoma and squamous cell carcinoma. To allow the use of various immunocytochemical stains on limited materials, we tried transferring cells from a given smear to multiple slides. Using touch-preparation samples of 215 surgically resected non-small cell lung carcinomas of confirmed histologic classification (adenocarcinoma,n = 101; squamous cell carcinoma,n = 114), we performed immunocytochemistry for thyroid transcription factor-1, napsin A, p40, p63, CK5/6 and desmocollin-3, and compared cytologic staining results with the corresponding resection.

METHODS

We examined: (a) the expressions of the above 6 antibodies on cells transferred from touch imprints of resected specimens, the extent of staining being considered positive if more than 5% of the area was stained, and (b) the sensitivity, specificity, positive predictive value and negative predictive value for each antibody.

RESULTS

The histologic corresponding rate with Papanicolaou staining was only 73%. Regarding the differentiation of adenocarcinoma from squamous cell carcinoma, the sensitivity and specificity for napsin A in adenocarcinoma were 80 and 97%, respectively, while those for p40 in squamous cell carcinoma were 84 and 98%, respectively.

CONCLUSION

The immunocytochemical expressions of napsin A and p40 in imprint cytology seem to be of great utility for the accurate histological differentiation of lung cancers.

Clinicopathological observation of primary lung enteric adenocarcinoma and its response to chemotherapy: A case report and review of the literature

Primary lung enteric adenocarcinoma is a rare type of invasive lung carcinoma. Its morphology and immunohistochemistry are those of colorectal carcinoma, but there is no associated primary colorectal carcinoma. The present study describes the case of a 53-year-old female who presented with an irritating cough and a mass around the right sternoclavicular joint. Comprehensive evaluation revealed involvement of the mediastinum, lungs, right sternoclavicular joint and right kidney. Biopsies from the mediastinal and right sternoclavicular joint tumors showed features of adenocarcinoma. Immunohistochemistry was positive for cytokeratin (CK)20 and caudal type homeobox transcription factor 2, and negative for CK7, thyroid transcription factor-1 and napsin A. Genotypic analysis identified the expression of wild-type epidermal growth factor receptor, Kirsten rat sarcoma viral oncogene homolog, serine/threonine-protein kinase B-Raf and UDP-glucuronosyltransferase 1-1. There was no expression of echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase and a moderate expression of excision repair cross-complementation group 1, ribonucleoside-diphosphate reductase large subunit and tubulin β-3 chain. A strong expression of thymidylate synthase and 677TC genotype expression of methylenetetrahydrofolate reductase was observed. Gastroscopy, enteroscopy, colorectal colonoscopy and positron emission tomography-computed tomography failed to find evidence of a gastrointestinal malignancy and primary lung enteric adenocarcinoma was diagnosed. The presence of multiple metastases did not permit curative surgery. The patient was treated with 3 monthly cycles of the XELOX chemotherapy regimen; the response was poor with progression of supraclavicular lesions. Treatment was switched to the TP regimen for 4 monthly cycles, which resulted in a significant reduction in the size of the lung lesions; however, the supraclavicular lesion responded poorly to the treatment. The patient then received 2 cycles of the FOLFIRI regimen; however, the lung and right supraclavicular lesions progressed, causing increased right upper limb pain. The pain was alleviated by palliative surgery. Following surgery, the DP regimen was employed. Follow-up of the patient remains ongoing. The present findings suggest that the early diagnosis and treatment of primary lung enteric adenocarcinoma is likely to improve patient outcome.

The expression of TTF-1 and Napsin A in early-stage lung adenocarcinoma correlates with the results of surgical treatment

Non-small cell lung cancer (NSCLC) accounts for 80 % of lung cancers, and lung adenocarcinoma (ADC) is one of the main types of NSCLC. Although there are several studies on the relationship between lung ADC immunohistochemical diagnostic markers (thyroid transcription factor 1 (TTF-1) and Napsin A) and survival, some aspects of those studies could be improved. We examined the significance of the commonly used lung ADC diagnostic markers, including TTF-1, Napsin A, and CK7, in the prognosis of early-stage lung ADC. One hundred and nineteen cases of early-stage lung ADC (N0) were selected from the prospective database of lung cancer (Jan 2000 to Dec 2009). The expression levels of TTF-1, Napsin A, and CK7 in inventoried specimens were analyzed using tissue microarray (TMA) and immunohistochemical (IHC) analysis, and the effect of the expression level of each marker on patients' survival was examined. The diagnostic sensitivity and specificity of each marker for lung ADC were as follows: TTF-1, 87.0 and 90.1 %; Napsin A, 72.2 and 90.4 %; and CK7, 94.6 and 76.0 %, respectively. Patients with high expression levels of TTF-1 and Napsin A, and high co-expression levels of TTF-1/Napsin A had better survival rates than those with low levels of expression (P < 0.05). The expression levels of CK7 were not related to patients' survival. Multivariate analysis showed that the expression levels of Napsin A and TTF-1/Napsin A are independent prognostic factors for survival. The IHC detection of TTF-1 and Napsin A in specimens should be routinely performed in postoperative early-stage lung ADC patients. Its significance lies not only in the differential diagnosis, but also in determining the prognosis.

Napsin A is a specific marker for ovarian clear cell adenocarcinoma

Ovarian clear cell adenocarcinoma has a relatively poor prognosis among the ovarian cancer subtypes because of its high chemoresistance. Differential diagnosis of clear cell adenocarcinoma from other ovarian surface epithelial tumors is important for its treatment. Napsin A is a known diagnostic marker for lung adenocarcinoma, and expression of napsin A is reported in a certain portion of thyroid and renal carcinomas. However, napsin A expression in ovarian surface epithelial tumors has not previously been examined. In this study, immunohistochemical analysis revealed that in 71 of 86 ovarian clear cell adenocarcinoma patients (83%) and all of the 13 patients with ovarian clear cell adenofibroma, positive napsin A staining was evident. No expression was observed in 30 serous adenocarcinomas, 11 serous adenomas or borderline tumors, 19 endometrioid adenocarcinomas, 22 mucinous adenomas or borderline tumors, 10 mucinous adenocarcinomas, or 3 yolk sac tumors of the ovary. Furthermore, expression of napsin A was not observed in the normal surface epithelium of the ovary, epithelia of the fallopian tubes, squamous epithelium, endocervical epithelium, or the endometrium of the uterus. Therefore, we propose that napsin A is another sensitive and specific marker for distinguishing ovarian clear cell tumors (especially adenocarcinomas) from other ovarian tumors.

Thymic neuroendocrine tumors (paraganglioma and carcinoid tumors): a comparative immunohistochemical study of 46 cases

Twenty-two paragangliomas from different anatomical sites and 24 thymic neuroendocrine carcinomas (carcinoid tumors) were analyzed for traditional and novel immunohistochemical markers. In the paraganglioma group, there were 8 men and 14 women between the ages of 23 and 79 years (mean, 46 years). Their symptoms depended on the location of the tumor and included neck swelling and Horner syndrome for neck tumors, whereas abdominal and chest pain was present in tumors of the abdomen and mediastinum, respectively. One patient had Carney triad. In the carcinoid group, the patients were 20 men and 4 women between the ages of 25 and 78 years (mean, 48 years). These patients were symptomatic with chest pain, shortness of breath, and dyspnea. One patient presented with multiple endocrine neoplasia syndrome. Complete surgical resection was accomplished in all patients. The 46 neuroendocrine tumors were evaluated for GATA-3, pancytokeratin, thryoid transcription factor 1 (TTF-1), napsin A, chromogranin A, and synaptophysin. All paragangliomas were universally positive for chromogranin A and synaptophysin, but negative for pancytokeratin, TTF-1, and napsin A. GATA-3 was expressed in 12 (55%) of 22 tumors. The thymic neuroendocrine carcinomas (carcinoid tumors) were universally positive for pancytokeratin, but negative for GATA-3 and napsin A. Chromogranin A and synaptophysin were expressed in 92% and 88% of cases, respectively, and TTF-1 in 4 (17%) of 24 cases. Based on these results, we recommend that the workup of neuroendocrine tumors should include not only the conventional neuroendocrine markers and pancytokeratin but also other markers such as GATA-3 and TTF-1 in order to arrive at a better interpretation.

RNA-Seq accurately identifies cancer biomarker signatures to distinguish tissue of origin

Metastatic cancer of unknown primary (CUP) accounts for up to 5% of all new cancer cases, with a 5-year survival rate of only 10%. Accurate identification of tissue of origin would allow for directed, personalized therapies to improve clinical outcomes. Our objective was to use transcriptome sequencing (RNA-Seq) to identify lineage-specific biomarker signatures for the cancer types that most commonly metastasize as CUP (colorectum, kidney, liver, lung, ovary, pancreas, prostate, and stomach). RNA-Seq data of 17,471 transcripts from a total of 3,244 cancer samples across 26 different tissue types were compiled from in-house sequencing data and publically available International Cancer Genome Consortium and The Cancer Genome Atlas datasets. Robust cancer biomarker signatures were extracted using a 10-fold cross-validation method of log transformation, quantile normalization, transcript ranking by area under the receiver operating characteristic curve, and stepwise logistic regression. The entire algorithm was then repeated with a new set of randomly generated training and test sets, yielding highly concordant biomarker signatures. External validation of the cancer-specific signatures yielded high sensitivity (92.0% ± 3.15%; mean ± standard deviation) and specificity (97.7% ± 2.99%) for each cancer biomarker signature. The overall performance of this RNA-Seq biomarker-generating algorithm yielded an accuracy of 90.5%. In conclusion, we demonstrate a computational model for producing highly sensitive and specific cancer biomarker signatures from RNA-Seq data, generating signatures for the top eight cancer types responsible for CUP to accurately identify tumor origin.

Evaluation of napsin A, TTF-1, p63, p40, and CK5/6 immunohistochemical stains in pulmonary neuroendocrine tumors

OBJECTIVE

A panel of immunohistochemical (IHC) stains frequently used to subclassify non-small cell lung cancers (NSCLCs) includes napsin A, TTF-1, CK5/6, p40, and p63. The expression profiles of these stains in neuroendocrine tumors have not been systematically evaluated.

METHOD

Sixty-eight resected pulmonary neuroendocrine tumors, including 52 typical carcinoids (TCs), eight atypical carcinoids (ACs), seven small cell carcinomas (SCLCs) and one large cell neuroendocrine carcinoma (LCNEC), were stained for napsin A, TTF-1, p63, p40, and CK5/6. Tumors were scored as positive (>1% tumor cells reactive) or negative, and percentage of reactive tumor cells was recorded.

RESULTS

Napsin A, p63, p40, and CK5/6 were consistently negative in neuroendocrine tumors. TTF-1 was positive in 17 of 52 TCs, 4 of 8 ACs, 5 of 7 SCLCs, and 0 of 1 LCNECs.

CONCLUSION

Pulmonary neuroendocrine tumors have a distinct but nonspecific profile on IHC panel commonly applied to subclassify NSCLCs. They are napsin A-/p40-/p63-/CK5/6-/TTF-1±. Recognizing this profile may have value in separating neuroendocrine tumors from NSCLCs.

The lung-specific proteome defined by integration of transcriptomics and antibody-based profiling

The combined action of multiple cell types is essential for the physiological function of the lung, and increased awareness of the molecular constituents characterizing each cell type is likely to advance the understanding of lung biology and disease. In the current study, we used genome-wide RNA sequencing of normal lung parenchyma and 26 additional tissue types, combined with antibody-based protein profiling, to localize the expression to specific cell types. Altogether, 221 genes were found to be elevated in the lung compared with their expression in other analyzed tissues. Among the gene products were several well-known markers, but also several proteins previously not described in the context of the lung. To link the lung-specific molecular repertoire to human disease, survival associations of pneumocyte-specific genes were assessed by using transcriptomics data from 7 non-small-cell lung cancer (NSCLC) cohorts. Transcript levels of 10 genes (SFTPB, SFTPC, SFTPD, SLC34A2, LAMP3, CACNA2D2, AGER, EMP2, NKX2-1, and NAPSA) were significantly associated with survival in the adenocarcinoma subgroup, thus qualifying as promising biomarker candidates. In summary, based on an integrated omics approach, we identified genes with elevated expression in lung and localized corresponding protein expression to different cell types. As biomarker candidates, these proteins may represent intriguing starting points for further exploration in health and disease.

The high diagnostic accuracy of combined test of thyroid transcription factor 1 and Napsin A to distinguish between lung adenocarcinoma and squamous cell carcinoma: a meta-analysis

Background

Accurate classification of non-small cell lung cancer (NSCLC) using morphological features has several limitations. However, the use of thyroid transcription factor 1 (TTF-1) and Napsin A as markers for the identification of various subtypes of NSCLC has shown promise. This meta-analysis was designed to evaluate the diagnostic value of combined TTF-1 and Napsin A test to distinguish lung adenocarcinoma from squamous cell carcinoma.

Methods

The Medline, EMBASE and Web of Science databases were searched, along with the reference lists of relevant articles (up to May 4, 2014). Ten studies containing 1,446 subjects were identified. The sensitivity, specificity, diagnostic odds ratio (DOR) and area under the summary receiver operating characteristics curve (AUC) were calculated to estimate the combined diagnostic value of TTF-1 and Napsin A.

Results

The pooled sensitivity and specificity were 0.76 (95% CI: 0.69–0.83) and 1.00 (95% CI: 0.92–1.00), respectively. The positive and negative likelihood ratios were 877.60 (95% CI: 8.40–91533.40) and 0.24 (95% CI: 0.18–0.32). The DOR was 3719 (95% CI: 33–414884). The AUC was 0.92 (95%CI: 0.89–0.94). The patient's location was a source of heterogeneity for sensitivity. The patient's location, the study's sample size and the threshold used to determine positive staining were consistently found to be sources of heterogeneity for specificity in subgroup analyses and meta-regression.

Conclusions

The combined test of TTF-1 and Napsin A presents a promising alternative method, useful to distinguish between lung adenocarcinoma and squamous cell carcinoma.

Renal metastasis from pulmonary adenocarcinoma: the pathologist's approach to an uncommon finding: case report and review of the literature

We herein report an uncommon case of renal metastasis from the lung in a 72-year-old man who 2 years before underwent surgical treatment for a pulmonary adenocarcinoma. During follow-up, a computed tomography scan revealed the presence of a solid mass located in the right kidney. Histopathologic and immunohistochemical examination of the enucleated lesion demonstrated the renal localization of an adenocarcinoma of the lung. Clinically recognized renal metastatic lesions from pulmonary cancer are a rare finding with only 35 cases reported to date in the English literature, and renal localization of adenocarcinoma of the lung is extraordinarily uncommon. Together with suggestive clinical data and negativity for markers of adenocarcinomas of different origin, thyroid transcription factor-1, when positive, is considered to be the most reliable marker for the differential diagnosis.

Napsin A expression in small cell carcinoma of the lung: a cytologic study with review of differentials

INTRODUCTION

Napsin A is a diagnostic marker for pulmonary adenocarcinoma and a useful alternative to thyroid transcription factor 1 (TTF-1). TTF-1 also stains pulmonary small cell carcinoma (SCCA). Napsin A expression in SCCAs is not as established as it is in non-SCCAs. We analyzed napsin A and TTF-1 expression in 36 previously confirmed cytologic cases of pulmonary SCCA. Ours is currently the largest cytologic series of such cases examined for napsin A expression.

MATERIALS AND METHODS

Thirty-six patients, (20 men, 16 women), age 43-87 years, mean 57 years, had primary or metastatic pulmonary SCCA diagnosed by fine-needle aspiration biopsies of mediastinum (n = 5); liver (n = 3); subcutaneous nodule (n = 1); lung (n = 6); and axillary, cervical, and mediastinal lymph nodes (n = 20), as well as a pleural effusion (n = 1). Napsin A and TTF-1 expression was tested. Also, previous expression (or lack thereof) with immunocytochemical stains pancytokeratin and neuroendocrine markers (synaptophysin, chromogranin, and cluster of differentiation marker CD56) were noted.

RESULTS

All cases of pulmonary SCCA were positive for pancytokeratin. TTF-1 was positive in 35 of 36 cases (97%), and napsin A was negative in all 36 cases (100%). All 36 cases expressed ≥ 1 neuroendocrine marker, including the TTF-1 negative case.

CONCLUSIONS

This study showed napsin A was negative in all pulmonary SCCAs. This stain may prove to be a useful exclusionary marker in distinguishing pulmonary SCCA from other poorly differentiated lung carcinomas with similar morphologic features, especially those with concomitant TTF-1 expression.

Lipase member H is a novel secreted protein selectively upregulated in human lung adenocarcinomas and bronchioloalveolar carcinomas

Lung cancer is one of the most frequent causes of cancer-related death worldwide. However, molecular markers for lung cancer have not been well established. To identify novel genes related to lung cancer development, we surveyed publicly available DNA microarray data on lung cancer tissues. We identified lipase member H (LIPH, also known as mPA-PLA1) as one of the significantly upregulated genes in lung adenocarcinoma. LIPH was expressed in several adenocarcinoma cell lines when they were analyzed by quantitative real-time polymerase chain reaction (qPCR), western blotting, and sandwich enzyme-linked immunosorbent assay (ELISA). Immunohistochemical analysis detected LIPH expression in most of the adenocarcinomas and bronchioloalveolar carcinomas tissue sections obtained from lung cancer patients. LIPH expression was also observed less frequently in the squamous lung cancer tissue samples. Furthermore, LIPH protein was upregulated in the serum of early- and late-phase lung cancer patients when they were analyzed by ELISA. Interestingly, high serum level of LIPH was correlated with better survival in early phase lung cancer patients after surgery. Thus, LIPH may be a novel molecular biomarker for lung cancer, especially for adenocarcinoma and bronchioloalveolar carcinoma.

A panel of four immunohistochemical markers (CK7, CK20, TTF-1, and p63) allows accurate diagnosis of primary and metastatic lung carcinoma on biopsy specimens

Accurate classification of lung cancer, as well as the differentiation between primary and metastatic carcinoma to the lung, mostly performed on biopsy or fine needle aspiration specimens, is critical for decisions on therapy and for determining prognosis. The limited amount of biopsy material available for morphological assessment has stimulated attempts to improve diagnostic accuracy through the use of immunohistochemistry (IHC), but an optimal IHC diagnostic algorithm has not been firmly established. We evaluated, on a retrospective series of biopsy specimens, the performance of a four-antibody IHC panel for accurate subclassification of non-small cell lung carcinoma (NSCLC) and for identification of metastatic carcinoma. Tumor morphology was assessed and IHC for CK7, CK20, TTF-1, and p63 was performed according to a two-step algorithm. Matched resection specimens served as gold standard and were compared with the corresponding biopsy. Of 443 biopsy specimens studied, 325 were diagnosed as primary carcinoma of the lung, 198 (44.7 %) as adenocarcinoma, 9 (2 %) as possibly adenosquamous carcinoma, 127 (28.7 %) as squamous cell carcinoma, and 40 (9 %) as NSCLC not further classifiable. Ten cases (2.3 %) were classified as adenocarcinoma of unknown origin and 58 (13 %) as metastasis. Importantly, of the primary lung adenocarcinomas, 35 (17.7 %) had been considered on clinical grounds as a metastasis from a previously diagnosed primary tumor. Of the 55 cases submitted to surgical resection in 47 (85.5 %) the biopsy diagnosis was confirmed, revealing substantial agreement (κ value = 0.757). Our two-step approach allows for accurate subclassification of NSCLC and also to distinguish between primary lung adenocarcinoma and metastasis, notably of colorectal adenocarcinoma, with crucial implications for appropriate patient management.

Napsin A expression in anaplastic, poorly differentiated, and micropapillary pattern thyroid carcinomas

Napsin A is a sensitive and specific marker for pulmonary adenocarcinoma versus squamous cell carcinoma. However, studies have shown that napsin A is also positive in approximately 5% of papillary thyroid carcinomas. The prevalence of napsin A in more aggressive types of thyroid carcinoma is unknown. Napsin A positivity in metastatic thyroid carcinoma, especially in conjunction with thyroid transcription factor-1 (TTF-1), could be misdiagnosed as lung adenocarcinoma. We investigated napsin A, TTF-1, and PAX8 expression in 26 anaplastic, 16 poorly differentiated, and 2 micropapillary pattern thyroid carcinomas. A focal micropapillary component was also present in 3 poorly differentiated and 3 anaplastic thyroid carcinomas. Four of 26 (15%) anaplastic, 2/16 (13%) poorly differentiated, and 2/2 (100%) micropapillary pattern thyroid carcinomas were napsin A positive. Three of the 6 cases (50%) with a focal micropapillary component were napsin A positive (1 of these 3 cases was positive only in the micropapillary component). All napsin A-positive cases were also positive for TTF-1, and all but 1 micropapillary pattern carcinoma were also PAX8 positive. In 1 case, napsin A was positive in the micropapillary component, but PAX8 was only positive in the adjacent poorly differentiated carcinoma. In summary, a minority of anaplastic and poorly differentiated thyroid carcinomas are napsin A positive. More importantly, napsin A expression is more common in carcinomas with a micropapillary component, a pattern shared in common with some lung adenocarcinomas. PAX8 may be diagnostically useful to distinguish these napsin A-positive thyroid carcinomas from lung adenocarcinomas, which are PAX8 negative.

Identification of HLA ligands and T-cell epitopes for immunotherapy of lung cancer

INTRODUCTION

Lung cancer is the most common cancer worldwide. Every year, as many people die of lung cancer as of breast, colon and rectum cancers combined. Because most patients are being diagnosed in advanced, not resectable stages and therefore have a poor prognosis, there is an urgent need for alternative therapies. Since it has been demonstrated that a high number of tumor- and stromal-infiltrating cytotoxic T cells (CTLs) is associated with an increased disease-specific survival in lung cancer patients, it can be assumed that immunotherapy, e.g. peptide vaccines that are able to induce a CTL response against the tumor, might be a promising approach.

METHODS

We analyzed surgically resected lung cancer tissues with respect to HLA class I- and II-presented peptides and gene expression profiles, aiming at the identification of (novel) tumor antigens. In addition, we tested the ability of HLA ligands derived from such antigens to generate a CTL response in healthy donors.

RESULTS

Among 170 HLA ligands characterized, we were able to identify several potential targets for specific CTL recognition and to generate CD8+ T cells which were specific for peptides derived from cyclin D1 or protein-kinase, DNA-activated, catalytic polypeptide and lysed tumor cells loaded with peptide.

CONCLUSIONS

This is the first molecular analysis of HLA class I and II ligands ex vivo from human lung cancer tissues which reveals known and novel tumor antigens able to elicit a CTL response.

Immunohistochemistry in the differential diagnostics of primary lung cancer: an investigation within the Southern Swedish Lung Cancer Study

OBJECTIVES

To assess immunohistochemical (IHC) stains differentially expressed between different types of lung cancer.

METHODS

We evaluated 16 different IHC stains in 209 prospectively included, surgically treated primary lung cancers, including 121 adenocarcinomas, 65 squamous cell carcinomas, 15 large-cell carcinomas, 5 adenosquamous carcinomas, 2 sarcomatoid carcinomas, and 1 small-cell carcinoma, using the tissue microarray technique.

RESULTS

Cytokeratin 5 (CK5) and P63 were both positive in 10% or more of the cells in 97% of the squamous cell carcinomas, with the former being positive (<10% of the cells) in only 2 non-squamous cell carcinomas. Thyroid transcription factor 1 (TTF1) and napsin A were positive in 10% or more of the cells in 88% and 87% of the adenocarcinomas, respectively, with 94% of the adenocarcinomas being positive in at least 1 marker. Fifteen percent of the adenocarcinomas were positive for estrogen receptor.

CONCLUSIONS

CK5, TTF1, and napsin A are sensitive markers for squamous cell carcinoma and adenocarcinoma of the lung.