Thyroid Transcription Factor-1 Expression Research Articles

Prediction of TTF-1 expression in non-small-cell lung cancer using machine learning-based radiomics.

To explore the feasibility and performance of machine learning-based radiomics models in predicting thyroid transcription factor-1 (TTF-1) expression in non-small cell lung cancer (NSCLC). A total of 227 NSCLC patients were included in this retrospective study and divided into the training set and test set with a ratio of 8:2 randomly. Lung tumors on CT images were semi-automatic segmented utilizing 3D Slicer. Radiomic features quantifying tumor intensity, shape, texture, and transformed wavelet were extracted using a Python toolkit. Variance threshold (VT), principal component analysis (PCA), and least absolute shrinkage selection operator (LASSO) were used to reduce features; logistic regression (LR), random forest (RF), and support vector machine (SVM) were used to develop classifier, respectively. The performance of the models was evaluated by areas under the curves (AUC) of receiver operating characteristic (ROC) curves. Different models were compared by the Delong test to determine the optimal algorithms. Total 1968 radiomic features were extracted from the lung tumors images, and then 13, 15, and 13 stable features were selected by VT, PCA, and LASSO, respectively. Each classifier could discriminate against the TTF-1-positive groups with average AUC ranging from 0.601 to 0.784 in the training set. Among the models, three models constructed by the LASSO method showed satisfactory performance in the test set with AUC ranging from 0.715 to 0.787. The Delong test showed no significant difference between the LASSO models (P > 0.05). Machine learning-based radiomics model could predict the expression of TTF-1 in NSCLC patients.

Expression and Clinicopathological Significance of SOX11 in Small-Cell Lung Cancer.

Objective This study aims to investigate the expression of neuronal transcription factor SOX11 in small-cell lung cancer (SCLC) and compare it with the expression of CD56 (nerve cell adhesion molecule), synaptophysin (Syn), chromogranin A (CgA), and thyroid transcription factor-1 (TTF-1) to explore the application value of SOX11 in the pathological diagnosis of SCLC. Methods Immunohistochemical methods were used to detect the expression of SOX11, TTF-1, CD56, Syn, and CgA in 120 lung tumor tissues, and experimental results were analyzed using SPSS23.0 statistical software. Results Immunohistochemical results showed that in the 120 lung tumor samples, SOX11 was highly expressed in SCLC and localized to the nucleus, with low or no expression in control carcinoid/lung neuroendocrine tumors, lung adenocarcinomas, and lung squamous cell carcinomas. Statistical analysis results revealed the following points. First, the expression of SOX11 was closely related to the tumor histological type. The expression of SOX11 in SCLC (positive rate of 63.33%) was significantly higher than that in carcinoid/neuroendocrine tumors (positive rate of 12.50%), lung adenocarcinoma (positive rate of 0%), and lung squamous cell carcinoma (positive rate of 0%). Second, immunohistochemical investigation of 60 SCLC cases revealed that the highest positive rates of CD56, TTF-1, and Syn, respectively, were 93.33 percent, 95 percent, and 86.67 percent. SOX11 also exhibited high sensitivity (0.633) and specificity (0.875) in SCLC. The positive rates of SOX11 and CgA were 63.33% and 50.00%, respectively. Statistical results revealed that the positive rate of CgA had no significant difference (P > 0.05). Lastly, the combined use of antibodies SOX11, CgA, CD56, Syn, and TTF-1 was more beneficial to improving the diagnosis rate of SCLC than the single use of one or two antibodies. Conclusion The expression of SOX11 in different histological types of lung tumors differs considerably. SOX11 is highly expressed in SCLC. SOX11 can be used as a beneficial supplement to the combination of classical neuroendocrine markers and in combination with CgA, CD56, Syn, and TTF-1 to assist in the diagnosis of SCLC.

Neuroendocrine tumors (NETs) - experience of a single Center.

Introduction: Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors arising from cells that are part of the diffuse neuroendocrine system. Patients, Materials and Methods: We conducted a retrospective study in which we included a number of 91 cases diagnosed with neuroendocrine tumors (NETs). Descriptive statistics was performed: number of cases based on location, distribution by gender (male/female), distribution by age, and we also performed a morphological and immunohistochemical (IHC) study. Results: The highest number of cases was found in lungs (60 cases). Tumors located on the skin, breast or bladder have been discovered, locations considered rare for this type of tumor. Of all cases diagnosed in the lungs, 59 were diagnosed as small cell carcinomas (SCCs) and only one case as NET. All surgical specimens were positive for chromogranin A (CgA), with a different expression for the other immunomarkers. For the lung biopsies, the most frequently IHC staining was CgA and cluster of differentiation 56 (CD56), with an increased positivity for the latter. Conclusions: CgA remains the most sensitive immunomarker in the diagnosis of NETs. CD56 is the most widely used immunomarker for diagnosing small cell lung tumors. Positive expression of thyroid transcription factor 1 (TTF1) immunomarker does not confirm pulmonary origin of SCCs.

The Extent of Expression of Thyroid Transcription Factor 1, Cytokeratin 7, and Anaplastic Lymphoma Kinase in Lung Adenocarcinoma.

Background:New forms of genetic alteration were developed giving a new era of lung adenocarcinoma (AdC) with diverse clinical and pathological features.Aim and Objectives:The aim is to investigate the ALK-rearranged gene as one of these genetic alterations in AdC. The role of TTF-1 and CK7 is to exclude the metastases.Material and Methods:Paraffin-embedded 50 AdC specimens were cut into 4-mm thick sections and stained with the primary antibody, using an anti-TTF-1 antibody, (all at a 1:200 dilution, mouse monoclonal antibody; Dako, Denmark), anti-CK 7 antibody (DAKO, Carpentaria, CA), and the rabbit monoclonal anti- ALK antibody (D5F3) (Ventana, USA). Positive reactivity was considered as brown nuclear immunostaining for TTF-1 and cytoplasmic for CK 7and both cytoplasmic and nuclear for ALK.Results:The median age was 56±2, with male to female ratio 7:3. Forty-four cases revealed a mixed pattern (88%), with focal intraluminal mucin. Forty-one cases (82%) were positive for TTF-1, of these; weak (13; %), moderate (16; %) and strong (12; %). Regarding CK7; 48 cases (96%) were positive; weak (7 cases; 14.5; %), moderate (18 cases; 37.5%) and strong (23 case; 47.9 %) of the positive cases. Regarding D5F3; five cases (10%) were positive; weak (1 case; 20 %), moderate (2 cases; 40 %) and strong (2 cases; 40%) out of the positive cases. Four ALK-positive cases were male and ALK-positive patients ranged from 42-55 years with median 48.Conclusion:Despite the incidence of ALk-AdC is uncommon, it might be suspected in lesions of lower age group especially with mucinous foci.

Impact of Quercus infectoria Galls Extract on Thyroid Gland and Testicular Functions in Diabetic Rats

Diabetes mellitus has been reported to be accompanied by thyroid and testicular dysfunctions. The objective of this study was to investigate the effect of Quercus infectoria galls (QIg) extract on the thyroid gland and testicular functions in diabetic rats. Sixteen rats were randomly divided into four equal groups, consisting of normal control, diabetic untreated control, diabetic treated with oral administration of 500 mg/kg BW and 1000 mg/kg BW, respectively for 15 days. Serum blood glucose, thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), testosterone (T), and luteinizing hormone (LH) were assessed. At the end of the experimental period, the rats were euthanized for histopathological analysis of thyroid gland and testis. Furthermore, immunohistochemistry was used to assess the expression of thyroid transcription factor-1 (TTF-1) in the thyroid gland of rats. The significant increase in serum blood glucose level in diabetic rats (DC) was markedly decreased by treatment with QIg extract (500 mg and 100 mg/kg BW) almost to the normal level. The reduced thyroid hormones, both the T3 and T4 were significantly recovered after 15 days of treatment with QIg extract (500 mg and 100 mg/kg BW). Whereas serum concentration of testosterone was significantly reduced in diabetic rats with QIg extract (500 mg and 100 mg/kg BW) treatment. Histopathological analysis of diabetic rats showed a wide range of morphological alterations in thyroid gland and testicular structures, which were almost completely, restored back to normal by treatment of rats with QIg extract. Furthermore, results showed overexpression of TTF-1 in the thyroid gland of diabetic rats, which was recovered back to normal expression after 15 days of treatment with QIg extract. These findings may provide new insights into the potential role of QIg extract as a promising therapeutic agent against diabetic complications in thyroid gland and testicular functions.

TTF-1: A Well-Favored Addition to the Immunohistochemistry Armamentarium as a Diagnostic Marker of SEGA

Subependymal giant cell astrocytoma (SEGA) is a World Health Organization grade 1 neoplasm, which, due to its dubious morphologic features, may be misdiagnosed as a high-grade tumor at times. This tumor shows binary immunoexpression including both glial and neural markers, leading to a state of diagnostic quandary. Recent evidences have surmised the diagnostic utility of thyroid transcription factor 1 (TTF-1), spurring us to study the practicality of this marker in distinguishing SEGAs from its mimics. In this study, TTF-1 immunohistochemistry using clone 8G7G3/1 (1:50) was performed in 38 cases of SEGA, 30 cases of central neurocytoma, 10 cases each of intraventricular glioblastoma and ependymoma, and 5 cases of cortical tubers. Additionally, serine/threonine-protein kinase B-Raf (BRAFV600E) mutation, a common genetic alteration in pediatric low-grade-glial tumors with neuronal-differentiation, was analyzed using Ventana immunohistochemistry platform. TTF-1 immunopositivity was seen in all 38 cases (100%) of SEGAs, with 20 cases (52.6%) showing diffuse (>50% of tumor area) expression while focal (<50%) immunopositivity was seen in 18 cases (47.3%). None of the cases demonstrated serine/threonine-protein kinase B-Raf immunolabeling. Barring 2 cases of neurocytoma (6.6%), all other cases including ependymoma, glioblastoma, and cortical tubers were immunonegative for TTF-1. The congruous finding of TTF-1 expression in SEGA and cells of the developing neuroepithelium in the medial ganglionic eminence hint toward a primogenitor cell with neoplastic potential in the presence of impelling factors.

Real-World Diagnostic Accuracy and Use of Immunohistochemical Markers in Lung Cancer Diagnostics.

Objectives: Accurate and reliable diagnostics are crucial as histopathological type influences selection of treatment in lung cancer. The aim of this study was to evaluate real-world accuracy and use of immunohistochemical (IHC) staining in lung cancer diagnostics. Materials and Methods: The diagnosis and used IHC stains for small specimens with lung cancer on follow-up resection were retrospectively investigated for a 15-month period at two major sites in Sweden. Additionally, 10 pathologists individually suggested diagnostic IHC staining for 15 scanned bronchial and lung biopsies and cytological specimens. Results: In 16 (4.7%) of 338 lung cancer cases, a discordant diagnosis of potential clinical relevance was seen between a small specimen and the follow-up resection. In half of the cases, there was a different small specimen from the same investigational work-up with a concordant diagnosis. Diagnostic inaccuracy was often related to a squamous marker not included in the IHC panel (also seen for the scanned cases), the case being a neuroendocrine tumor, thyroid transcription factor-1 (TTF-1) expression in squamous cell carcinomas (with clone SPT24), or poor differentiation. IHC was used in about 95% of cases, with a higher number of stains in biopsies and in squamous cell carcinomas and especially neuroendocrine tumors. Pre-surgical transthoracic samples were more often diagnostic than bronchoscopic ones (72–85% vs. 9–53% for prevalent types). Conclusions: Although a high overall diagnostic accuracy of small specimens was seen, small changes in routine practice (such as consequent inclusion of p40 and TTF-1 clone 8G7G3/1 in the IHC panel for non-small cell cancer with unclear morphology) may lead to improvement, while reducing the number of IHC stains would be preferable from a time and cost perspective.

TTF1-positive SMARCA4/BRG1 deficient lung adenocarcinoma.

SMARCA4/BRG1-deficient lung adenocarcinoma (SD-LUAD) is being recognized as a distinct subtype based on subtle differences in its clinical, morphological, and immunophenotypic attributes compared to other non–small cell lung carcinomas. We present here a case of SD-LUAD with curious thyroid transcription factor 1 (TTF1) expression in a morphologically heterogenous lung adenocarcinoma. The better differentiated area showed preservation of TTF1 expression, and a poorly differentiated tumor had loss of TTF1 expression with universal BRG1 loss.

P60.04 TTF1 Expression in Advanced Lung Adenocarcinoma and Survival Outcome: An Observational Study

Prognosis of advanced lung adenocarcinoma remains poor despite significant advances in treatment options. Current literature calls for independent prognostic biomarkers to better stratify patient risk. Thyroid transcription factor 1 (TTF1) is regulatory protein that is suggested to be a favourable prognostic indicator independent of stage at diagnosis. The mechanism for this remains unclear with loss of differentiation of tumour a possible explanation. Further research, however, is needed for clinical application. This study explores TTF1 expression in adenocarcinoma of the lung and its correlation to survival outcomes as well as explores patterns of incidence in relation to tumour grade, gain of function mutations and PD-L1 status. This is a retrospective, observational, single-centre study of lung adenocarcinoma diagnosed between July 2017 and July 2020 in a large regional cancer centre in Victoria, Australia. Immunohistochemical reports and patient specific data were collected from patient records and analysed with simple descriptive statistics, binomial testing and Kaplan-Meier survival curves. A total of 86 adenocarcinoma of lung primary cases were identified (Age Range 49-89, Mean 69, ratio female to male 56%:44%). Of the total cases, 83% were TTF1 positive (n=71) and 13% negative (n=10). Gain of function mutations were present in 10.5% (n=9) of the cohort, with majority of these cases being TTF1 positive (78%, n=7). PD-L1 status analysis was completed in 44.7% of cases, with a majority being TTF1 positive (80% n=20). Overall, TTF1 negative tumours appeared more likely to be poorly differentiated (p=0.02), however TTF1 positive tumours did not have a significant association with well differentiated tumours (p=0.56). Overall, TTF1 positive tumours had a significantly longer survival compared to TTF1 negative tumours (median survival 64.7 weeks vs 9.4 weeks, on univariate analysis p<0.0004) . TTF1 positive tumours seem to have a longer overall survival regardless of their PD-L1 status, compared to the TTF1 negative group (p=0.04). TTF-1 expression in lung adenocarcinoma appears to be a good prognostic indicator regardless of PD-L1 status. Whilst TTF-1 negative status appears to be correlated with poorly differentiated tumours, positive TTF1 status does not necessarily reflect a degree of differentiation. These findings, are hypothesis generating and being planned to be validated in a larger cohort in a prospective manner, to define the clinical utility of TTF1 as a predictive/prognostic biomarker.

CDK14 expression is elevated in patients with non-small cell lung cancer and correlated with poor prognosis.

ObjectiveTo investigate the clinical significance of cyclin-dependent kinase 14 (CDK14) expression in patients with non-small cell lung cancer (NSCLC).MethodsThe present prospective observational study included 193 patients diagnosed with NSCLC between January 2010 and December 2014. NSCLC tumor tissues and paired paracancerous normal tissues were obtained from all patients. CDK14, thyroid transcription factor 1 (TTF-1), cytokeratin 5/6 (CK5/6), and Ki67 expression was measured via immunohistochemistry (IHC)ResultsCDK14 staining was strong (>3) in 129 patients (66.49%) and weak (≤3) in 64 patients (33.16%). The mean IHC scores were markedly higher in tumor tissues than in paracancerous tissues. Pearson’s analysis demonstrated that the IHC scores of CDK14 expression were positively correlated with TTF-1, CK5/6, and Ki67 scores. Kaplan–Meier analysis illustrated that 5-year overall survival was markedly longer in patients with weak CDK14 staining. TNM stage, pleural invasion, lymph node metastasis, CDK14 expression, and Ki67 expression were risk factors for 5-year overall survival in patients with NSCLC.ConclusionCDK14 overexpression portended poor outcomes in patients with NSCLC, and CDK14 expression was correlated with TTF-1, CK5/5, and Ki67 expression.

78P Prognostic value of thyroid transcription factor-1 expression in lung adenocarcinoma in patients treated with anti PD-1/PD-L1

Anti-PD1/PD-L1-directed immune checkpoint inhibitors (ICI) are game changers in advanced non-small-cell lung cancer (NSCLC), but biomarkers are lacking. The aim of our study was to find clinically relevant biomarkers of the efficacy of ICI in non-squamous NSCLC.

Transcription start site-level expression of thyroid transcription factor 1 isoforms in lung adenocarcinoma and its clinicopathological significance.

There are multiple transcription start sites (TSSs) in agreement with multiple transcript variants encoding different isoforms of NKX2‐1/TTF‐1 (thyroid transcription factor 1); however, the clinicopathological significance of each transcript isoform of NKX2‐1/TTF‐1 in lung adenocarcinoma (LAD) is unknown. Herein, TSS‐level expression of NKX2‐1/TTF‐1 isoforms was evaluated in 71 LADs using bioinformatic analysis of cap analysis of gene expression (CAGE)‐sequencing data, which provides genome‐wide expression levels of the 5′‐untranslated regions and the TSSs of different isoforms. Results of CAGE were further validated in 664 LADs using in situ hybridisation. Fourteen of 17 TSSs in NKX2‐1/TTF‐1 (80% of known TSSs in FANTOM5, an atlas of mammalian promoters) were identified in LADs, including TSSs 1–13 and 15; four isoforms of NKX2‐1/TTF‐1 transcripts (NKX2‐1_001, NKX2‐1_002, NKX2‐1_004, and NKX2‐1_005) were expressed in LADs, although NKX2‐1_005 did not contain a homeodomain. Among those, six TSSs regulated NKX2‐1_004 and NKX2‐1_005, both of which contain exon 1. LADs with low expression of isoforms from TSS region 11 regulating exon 1 were significantly associated with poor prognosis in the CAGE data set. In the validation set, 62 tumours (9.3%) showed no expression of NKX2‐1/TTF‐1 exon 1; such tumours were significantly associated with older age, EGFR wild‐type tumours, and poor prognosis. In contrast, 94 tumours, including 22 of 30 pulmonary invasive mucinous adenocarcinomas (IMAs) exhibited exon 1 expression without immunohistochemical TTF‐1 protein expression. Furthermore, IMAs commonly exhibited higher exon 1 expression relative to that of exon 4/5, which contained a homeodomain in comparison with EGFR‐mutated LADs. These transcriptome and clinicopathological results reveal that LAD use at least 80% of NKX2‐1 TSSs and expression of the NKX2‐1/TTF‐1 transcript isoform without exon 1 (NKX2‐1_004 and NKX2‐1_005) defines a distinct subset of LAD characterised by aggressive behaviour in elder patients. Moreover, usage of alternative TSSs regions regulating NKX2‐1_005 may occur in subsets of LADs.

Thoracic nuclear protein in testis (NUT) carcinoma: expanded pathological spectrum with expression of thyroid transcription factor-1 and neuroendocrine markers.

Nuclear protein in testis (NUT) carcinoma, an aggressive tumour driven by NUTM1 rearrangements, often involves the lung/mediastinum and shows squamous differentiation. We encountered an index patient with a thoracic NUT carcinoma diagnosed by molecular testing, showing extensive pleural involvement and diffuse thyroid transcription factor-1 (TTF-1) expression, initially suggestive of lung adenocarcinoma with pseudomesotheliomatous growth. We thus gathered an institutional series of thoracic NUT carcinomas to examine their pathological spectrum. We searched for thoracic NUT carcinomas in our surgical pathology files and in 2289 consecutive patients with primary thoracic tumours investigated with RNA-based assays. We performed NUT immunohistochemistry on 425 additional lung adenocarcinomas. Collectively, we identified six patients (five men and one woman; age 31-80years; four never-smokers) with thoracic NUT carcinomas confirmed by molecular testing (including five with positive NUT immunohistochemistry). They died at 2.3-12.9months (median, 2.8months) after presentation. Two patients were diagnosed by histopathological assessment, and the remaining four (including the index patient) were diagnosed by molecular testing. Analysis of the index case revealed expression of multiple neuroendocrine markers and TTF-1; no ultrastructural evidence of neuroendocrine differentiation was noted. No additional NUT-positive cases were found by immunohistochemical screening. Although NUT carcinoma classically shows squamous differentiation, it can rarely express TTF-1 (even diffusely) and/or multiple neuroendocrine markers. This immunophenotypic spectrum may lead to diagnostic confusion with pulmonary adenocarcinoma, neuroendocrine tumour, and others. To circumvent this pitfall, NUT immunohistochemistry and/or NUTM1 molecular testing should be considered in primitive-appearing tumours, regardless of their immunophenotypic features.

Histological characteristics of lung adenocarcinoma with uncommon actionable alterations: special emphasis on MET exon 14 skipping alterations.

In the evolving era of precision medicine, increasing emphasis is placed on detecting molecular alterations driving the development of specific cancers and targeting them with matched therapies that can yield the best outcomes for patients. Lung adenocarcinomas with uncommon actionable alterations, including MET exon 14 skipping (METex14), ERBB2 and BRAF mutations, are rare and poorly characterised cancers. To more clearly understand the histopathological features of lung adenocarcinoma with uncommon actionable alterations, we compared the histological features of 678 cases with mitogenic driver alterations from 996 surgically resected lung adenocarcinomas. Genomic data from our cohort revealed METex14, ERBB2 and BRAF mutations in 13, 16 and 15 cases, respectively. Patients who had lung adenocarcinoma with METex14 were often elderly females. Histological features such as clear cell features (23%), hyaline globules (31%) and nuclear pleomorphism (39%) were the most frequently identified in METex14-positive cases; among those, three cases (23%) had tumour cells with bizarre giant or multilobulated nuclei. Additionally, the micropapillary pattern was the most frequently identified in ERBB2-mutated lung adenocarcinoma (31%). Lung adenocarcinoma with BRAF mutations tended to be less invasive, and the BRAF V600E mutation was identified in only one case with lepidic adenocarcinoma. Immunohistochemically, all METex14, ERBB2 and BRAF-positive tumours, except for invasive mucinous adenocarcinoma, were positive for thyroid transcription factor 1 (TTF-1). Our data from Japanese patients showed that lung adenocarcinoma with METex14 had unique clinicopathological characteristics: tumour cells with marked nuclear pleomorphism, hyaline globules and expression of TTF-1 in elderly women who never or lightly smoked.

Aberrant expression of thyroid transcription factor-1 in meningeal solitary fibrous tumor/hemangiopericytoma.

Meningeal solitary fibrous tumor (SFT) and hemangiopericytoma (HPC) were categorized as the same entity in the World Health Organization (WHO) 2016 classification of tumors of the central nervous system (CNS). Although NAB2-STAT6 fusion protein can be used to distinguish most of SFT/HPC from the other sarcomas, additional biomarkers were requested to separate meningeal SFT/HPC from meningioma and the molecular pathological difference between meningeal SFT/HPC and extra-CNS SFT/HPC still remains unclear. In this study, we evaluated the expression of TTF-1 in 67 meningeal SFT/HPC, 62 extra-CNS SFT/HPC and 201 meningiomas samples with immunohistochemistry (IHC) assays. The results showed that TTF-1 was detected in 23 of 67 (34.3%) meningeal SFT/HPC, 3 retroperitoneum SFT/HPC and none of meningiomas. Meanwhile, the copy number variation and mRNA expression of TTF-1 were measured by real-time quantitative PCR (qPCR) in meningeal SFT/HPC. These results demonstrated that TTF-1 protein expression level was significantly correlated with its transcription level, but independently related to the gene copy number variant. In conclusion, our study suggested that a large proportion of meningeal SFT/HPC was positive to TTF-1, while very few extra CNS SFT/HPC cases and no meningiomas were stained. So TTF-1 has value as an auxiliary diagnostic marker for meningeal SFT/HPC.

Comprehensive molecular analysis of genomic profiles and PD-L1 expression in lung adenocarcinoma with a high-grade fetal adenocarcinoma component.

BackgroundFetal adenocarcinoma of the lung is a rare variant of lung adenocarcinoma and is subcategorized into low-grade and high-grade (H-FLAC) fetal adenocarcinoma. We previously reported poor prognosis in pulmonary adenocarcinomas with an H-FLAC component; however, the genetic abnormalities involved in H-FLAC remain unclear. Therefore, this study aimed to elucidate molecular abnormalities as potential therapeutic targets for H-FLACs.MethodsWe performed immunohistochemical analysis and comprehensive genetic analyses using whole-exome sequencing in 16 lung cancer samples with an H-FLAC component. DNA was extracted from formalin-fixed paraffin-embedded tissues after macrodissection of the H-FLAC component.ResultsCancer-related mutations were identified in TP53 (7/16 cases), KMT2C (6/16 cases), KRAS (4/16 cases), NF1 (3/16 cases), STK11 (3/16 cases), CTNNB1 (2/16 cases), and EGFR (1/16 cases). A high tumor mutation burden of ≥10 mutations per megabase was observed in 3/16 cases. A high microsatellite instability was not detected in any case. Based on the cosine similarity with the Catalogue of Somatic Mutations in Cancer mutational signatures, H-FLACs were hierarchically clustered into three types: common adenocarcinoma-like (five cases), surfactant-deficient (ten cases), and signatures 2 and 13-related (one case). All common adenocarcinoma-like cases presented thyroid transcription factor-1 (TTF-1) expression, whereas surfactant-deficient cases often presented loss of TTF-1 and surfactant protein expression and included cases with mutations in the surfactant system genes NKX2-1 and SFTPC. H-FLACs displayed low programmed death ligand-1 (PD-L1) expression (1–49% of tumor cells) in 5/16 cases, and no case displayed high PD-L1 expression (≥50% of tumor cells).ConclusionsThis study indicates that lung cancers with an H-FLAC component rarely harbor currently targetable driver gene mutations for lung cancer but display a high frequency of KMT2C mutations. The microsatellite instability, tumor mutation burden, and PD-L1 expression status suggest a poor response to immune checkpoint therapy.

Aberrant thyroid transcription factor-1 expression in ovarian and nasopharyngeal carcinoma: Case reports with review of literature

Introduction: Thyroid transcription factor-1 (TTF-1) is the recommended and sensitive immunohistochemical (IHC) marker for diagnosing lung adenocarcinomas and thyroid neoplasms, at the primary as well as the metastatic site, and is useful to rule out these sites in cases with adenocarcinomas of unknown primary. However, aberrant nuclear TTF-1 expression has also been reported in malignancies arising from gastrointestinal tract (GIT), breast carcinoma, female genital tract (FGT), and colon. Here, we present our experience of aberrant expression of TTF-1 in ovarian and nasopharyngeal carcinoma (NPC). Materials and Methods: TTF-1 immunostain was performed on 16 cases of NPC using clones SP141 and 8G7G3/1. A case of ovarian serous carcinoma with aberrant TTF-1 expression has also been discussed. Results: Of 16 cases of NPC, 2 cases (12.5%) showed strong TTF-1 expression with clone SP141, while all were negative with 8G7G3/1. In one of the case initial diagnosis of metastatic lung adenocarcinoma was made on cervical node biopsy as the tumor was negative for p40 and showed strong nuclear positivity for TTF-1 (SP141 clone). However, on clinical suspicion of NPC Epstein-Barr virus-encoded small RNA (EBER) by in situ hybridization was performed which was positive, and repeat TTF-1 using clone 8G7G3/1 was negative, suggested a NPC. In the case of ovarian tumor, cells were strongly positive for CK7 and TTF-1 (SP141 clone) expression, and thus the tumor was erroneously diagnosed as metastatic adenocarcinoma from a primary lung. However, IHC in the resected specimen showed strong expression for PAX-8 and TTF-1 using SP141 clone, while negative with clone 8G7G3/1 clone (Ventana), leading to final diagnosis of high-grade serous carcinoma of ovary with aberrant TTF-1 expression. In this case, addition of PAX-8 in initial biopsy diagnosis would have saved from labeling it as primary from lung. Conclusion: The sensitivity and aberrant expression vary between the various antibody clones used, with increased expression seen by SP141 clone as compared to 8G7G3/1 in our cases. Our findings highlight the significance of using a panel of diagnostic IHC markers before final diagnosis and importance of clinical details.

Immunoexpression of TTF1 and p63 Differentiates Lung Adenocarcinomas in Sputum Samples.

Context:Differentiating NSCLC as either adeno or squamous type and identification of Epidermal Growth Factor Receptor (EGFR) mutations is clinically relevant for lung cancer patients for selecting treatment. Thyroid transcription factor-1 (TTF-1) and p63 were demonstrated as useful markers for histologic typing of lung cancer. Mutation and overexpression of EGFR has been reported in a subset of non-small cell lung cancers. If these markers can be validated for the differential diagnosis of adenocarcinoma in a sputum sample itself, it will be highly beneficial for lung cancer patients.Aims:To evaluate whether immunocytochemical expression of TTF-1, p63, and EGFR proteins in sputum samples can be used for differential diagnosis of lung adenocarcinoma by comparing with that of the corresponding tissue samples.Settings and Design:Ninety sputum samples and matched tissue samples were used for the study.Subjects and Methods:Monolayered smears and cell blocks of sputum and the corresponding tissue samples were immunostained with the standard ABC method. The expression patterns of these markers were analyzed statistically and compared with clinic-pathological parameters.Statistical Analysis Used:Chi-square test and paired t-test.Results:The p63 protein had a positive expression in 73.9% of SCC whereas TTF1 had positive expression in 75.8% of ADC. The EGFR expression was positive in 27 cases of adenocarcinoma, 21 cases of SCC and 19 cases of NSCLC.Conclusions:Immunocytochemistry of the aforementioned antibodies in sputum samples can be used as supplementary evidence for the subtyping of NSCLC.

Prognostic value of Thyroid Transcription Factor-1 expression in lung adenocarcinoma in patients treated with anti PD-1/PD-L1

ABSTRACT Anti-PD1/PD-L1-directed immune checkpoint inhibitors are game changers in advanced non-small-cell lung cancer, but biomarkers are lacking. The aim of our study was to find clinically relevant biomarkers of the efficacy of ICI in non-squamous NSCLC. We conducted a retrospective study of patients receiving ICI for advanced non squamous NSCLC in two cohorts. For a subset of patients, RNAseq data were generated on tumor biopsy taken before ICI. The primary end point was progression-free survival under ICI. Secondary end point was overall survival from ICI initiation. In the cohort, we studied 231 patients. Clinico-pathological characteristics included KRAS mutant status (n = 88), TTF1-positive expression (n = 136), LIPI (Lung Immune Prognostic Index) score of 0 (n = 116). In our cohort, lack of TTF1 expression, LIPI score >0, line of treatment >1, and liver metastases were associated with poorer PFS. TTF1 and PD-L1 status could be used to stratify survival and improve the AUC for prediction of prognosis in comparison with the PD-L1 gold standard. Using an external cohort of 154 patients, we confirmed the independent prognostic role of TTF1. TTF1 expression and PD-L1 can be used to stratify risk and predict PFS and OS in patients treated with ICI for NS-NSCLC.

Functional and clinical significance of ROR1 in lung adenocarcinoma

BackgroundReceptor tyrosine kinase-like orphan receptor 1 (ROR1) is normally detectable in embryonic tissues and absent in adult tissues. ROR1 was shown to inhibit apoptosis, potentiate EGFR signaling and reported to be overexpressed and associated with poor prognosis in several tumor models. This study aimed to assess the expression of ROR1 in lung adenocarcinoma (AC) patients.MethodsWe analyzed ROR1 expression by quantitative real-time PCR (qRT-PCR) in 56 histologically confirmed lung AC, stage I to IV, in addition we evaluated its association with TTF-1 (thyroid transcription factor-1) expression and the main molecular alterations involved in lung cancerogenesis.ResultsROR1 overexpression was observed in 28.6% of the entire cohort, using a cut-off of 1, or in 51.8% of the cases using the median value as threshold. Among patients without any genetic alteration, ROR1 overexpression was observed in 34.8% considering a cut-off of 1 and 52.2% considering the median value. The distribution of ROR1 was homogeneous among the different molecular categories: we found no association of ROR1 expression and the presence of gene mutations/rearrangements or the expression of TTF-1.ConclusionsROR1 overexpression could constitute a potential therapeutic target because altered in a consistent number of lung AC, especially in cases without druggable genetic alterations. ROR1 expression is independent of classical lung cancer molecular alterations and not correlated, in a Caucasian cohort, to TTF-1 expression.