TRPS1 as a novel immunohistochemical marker in breast cancer diagnosis

Utility of TRPS-1 immunohistochemistry in diagnosis of metastatic breast carcinoma in cytology specimens

TRPS1 expression in primary and metastatic prostatic adenocarcinoma, muscle invasive bladder urothelial carcinoma, and breast carcinoma: Is TRPS1 truly specific and sensitive for a breast primary?

IntroductionBreast cancer, especially triple-negative breast cancer (TNBC), lacks sensitive and specific diagnostic markers that can reliably differentiate it from carcinomas of other origins. TRPS1 is a relatively new immunohistochemical (IHC) marker that has demonstrated higher sensitivity in breast cancer, including TNBC. However, with the increasing use of this marker, broader immunoreactivity has been observed. This study aims to evaluate the utility of TRPS1 for establishing carcinoma of mammary origin. We compared the diagnostic sensitivity and specificity of TRPS1 with that of other IHC markers (GATA3 and SOX10).MethodsIn this retrospective study, we reviewed TRPS1 IHC performed at our center between 07/2022 and 06/2024, to evaluate the expression of TRPS1 in breast carcinoma (primary and distant metastasis) and in other malignancies. The sensitivity and specificity of TRPS1 in determining carcinoma of breast origin were compared with those of GATA3 and SOX10.ResultsThe study cohort comprised 106 cases, including 17 cases at the primary site, and 89 samples of distant metastasis. After correlation with morphology, immunophenotype and molecular studies, 94 cases (88.7%) were characterized as breast primary (37.9% ER+/HER2neu-, 4.6% ER-/HER2neu+, 1.1% ER+/HER2neu+, 56.3% TNBC), whereas 12 (11.3%) were non-breast primary. The non-breast primary sites included lung, bladder, Mullerian, and gastrointestinal. The sensitivity and specificity of TRPS1 were 93.6% and 58.3%, respectively. Conversely, GATA3 demonstrated a sensitivity and specificity of 76.9% and 66.7%, respectively. SOX10 exhibited the lowest sensitivity at 47.9%, but with the highest specificity at 100%. There were three cases of metastatic breast carcinoma (sites: bladder, lung, and bone), where TRPS1 was the only positive marker, whereas GATA3 and SOX10 were negative. TRPS1 showed a higher positivity rate (92.0%) in TNBC compared to GATA3 (63.4%) and SOX10 (56.7%). TRPS1 expression was also observed in other tumor types, including carcinoma of Mullerian origin, bladder, and lung, limiting its utility in the differential diagnosis.ConclusionOur study demonstrated a higher sensitivity of TRPS1 expression in establishing carcinoma of breast origin compared with GATA3 and SOX10, consistent with previous reported studies. However, the specificity of TRPS1 was lower than that of GATA3 and SOX10. These findings suggest that while TRPS1 can be used as a reliable marker for breast cancer, its expression in other tumor types should be carefully interpreted to avoid diagnostic pitfalls.

Background. Triple-negative breast cancer (TNBC), the most difficult subtype to treat, is defined as estrogen receptor, HER2, and progesterone receptor negative. TNBC constitutes 10-20% of all breast cancer and has a higher rate of distal recurrence and a poorer prognosis than other breast cancer subtypes. Less than 30% of women with metastatic TNBC survive 5 years and almost all die from their disease despite adjuvant chemotherapy. Angiogenesis is a critical factor in the development of tumors and metastases in numerous cancers. Clinical trials with anti-angiogenic drugs showed to be inadequate, with moderate response rates and insignificant survival gains for patients. To understand the genetic forces involved in TNBC, we performed a transposon mutagenesis screen in Pten mutant mice that identified several candidate trunk drivers and progression genes. A major finding of our screen was the discovery and functional validation of, Trichorhinophalangeal syndrome type 1 (TRPS1), a GATA-like transcription factor, which functions as a transcriptional repressor or activator, depending on cell type, stage of development, or pathological conditions. Based on this data, we explored the role of TRPS1 in angiogenesis. Methods and Results. Tube formation and sprouting assays were performed using overexpression and inactivation of TRPS1 in MDA-MD-231 and HCC70 cells, respectively. Interestingly, inactivation of TRPS1 expression accelerates tube formation structures compared to the vector control as well as cell branching in the sprouting assay. Overexpression of TRPS1 prevents tubing and branching formation in vitro assays. Moreover, immunohistochemistry staining of CD31 detected a reduced number of blood vessels in MDA-MB-231 tumor xenografts overexpressing TRPS1, and an increase of angiogenic vasculature in HCC70 TRPS1-shRNA tumor xenografts. In vitro and in vivo assays demonstrate the role of TRPS1 in tumor angiogenesis. Furthermore, human ChIP qPCR angiogenesis array identified 10 top candidate genes potentially regulated by TRPS1 transcription factor. Of these candidates, JAG1 and TYMP showed to have a higher fold enrichment compared to other angiogenic related genes. Finally, we validated its direct functional binding by using luciferase reporter assay, such demonstrated that TRPS1 is a direct transcriptional regulator of JAG1 and TYMP. Conclusion. TRPS1 is a tumor suppressor involved in the mechanisms regulating tumor angiogenesis by repressing the expression of JAG1 and TYMP genes in TNBC. Citation Format: Liliana Guzman. TRPS1 inhibits angiogenesis in triple negative breast cancer down regulating JAG1 and TYMP genes involved in angiogenesis pathways. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4607.

Introduction: Defining the origin of metastatic cancer is crucial for establishing an optimal treatment strategy, especially when obtaining sufficient tissue from secondary malignancies is limited. While cytological examination is often used in this diagnostic setting, morphologic analysis alone often fails to differentiate metastases derived from the breast from other primaries. The hormone receptor, human epidermal growth factor receptor-2, gross cystic disease fluid protein 15, and mammaglobin immunohistochemistry are often used to diagnose metastatic breast cancer. However, their effectiveness decreases in estrogen receptor (ER)-negative breast cancers, including the triple-negative breast cancer (TNBC) subtype. Methods: We conducted a comprehensive evaluation of GATA-binding protein 3 (GATA-3), trichorhinophalangeal syndrome type 1 (TRPS-1), and Matrix Gla Protein (MGP) immunochemistry across 140 effusion cytology specimens with metastatic adenocarcinoma derived from various primaries, including the breast, colon, pancreaticobiliary, lung, tubo-ovarian, and stomach. Results: The expression rates of these immunomarkers were significantly higher in metastatic cancers originating from the breast than other primaries. In TNBC, TRPS-1 (80.00%) and MGP (65.00%) exhibited higher positivity rates compared to GATA-3 (40.00%). Additionally, our data suggest that an immunohistochemical panel comprising MGP, GATA-3, and TRPS-1 significantly enhances the detection of metastatic breast cancer in effusion cytology specimens, including TNBC in particular. When considering dual-marker positivity, the diagnostic accuracy was found to be 89.29% across all breast cancer subtypes and 92.93% for TNBC. Conclusions: MGP appears to be a robust marker for identifying metastatic breast cancer in malignant effusions, especially TNBC. MGP notably enhances diagnostic accuracy when incorporated together with GATA-3 and TRPS-1 in an immunohistochemical panel.

ObjectivesWe explored Trichorhinophalangeal syndrome type 1 (TRPS1) expression in special types of breast carcinoma, and analyzed the correlation between TRPS1 and androgen receptor (AR) expression in triple-negative breast cancer (TNBC).MethodsTRPS1 expression was analyzed in 801 patients with special types of breast carcinoma. A total of 969 TNBC were used to analyze the correlation between the expression of TRPS1 and AR. TRPS1 expression was evaluated in 1975 cases of breast cancer with different molecular types.ResultsA total of 801 special types of breast cancers were stained with TRPS1.TRPS1 was positive in 100% (63/63) of mucinous carcinoma, 100% (7/7) adenoid cystic carcinomas (4 classic adenoid cystic carcinomas and 3 solid-basaloid adenoid cystic carcinomas), 100% (4/4) tubular carcinomas, 100% (2/2) secretory carcinomas, and 99.59% (243/244) invasive lobular carcinomas, 99.26% (267/269) invasive micropapillary carcinomas, 97.44% (38/39) ER-positive neuroendocrine tumors, 94.44% (34/36) metaplastic breast carcinomas (MBCs), 63.73% (65/102) apocrine carcinomas. TRPS1 was negative in all triple-negative neuroendocrine carcinomas (0/7).TRPS1 was positive in 92.86% (26/28) of metastatic special types of breast cancer. TRPS1 and AR expression were analyzed in 969 cases of TNBC. 90.40% were positive for TRPS1, and 42.41% were positive for AR. A significant inverse correlation between TRPS1 and AR expression was shown in TNBC (p < .001). TRPS1 showed a higher positive rate (93.13%) in TNBC compared to GATA binding protein 3 (GATA3), gross cystic disease fluid protein 15 (GCDFP-15) and forkhead box transcription Factor C 1 (FOXC1).ConclusionsIn conclusion, our study demonstrated that TRPS1 is a highly sensitive marker for most special types of breast carcinoma. TRPS1 was positive in 63.73% of apocrine carcinomas. TRPS1 and AR expression was inversely correlated in TNBC.

TRPS1: a highly sensitive and specific marker for breast carcinoma, especially for triple-negative breast cancer.

BackgroundBreast cancer is a heterogeneous disease consisting of different subtypes. Trichorhinophalangeal syndrome type 1 (TRPS1) gene, a GATA-type transcription factor, has been found to be highly expressed in breast cancer. Epithelial-to-mesenchymal transition (EMT) is known to play an important role in tumour invasion and metastasis. Our objective was to elucidate the different roles and clinical relevance of TRPS1 in different estrogen receptor (ER) expression subtypes of breast cancer.MethodsAn immunohistochemical study was performed. The correlation between clinicopathological features and other biomarker profiles were analysed statistically.ResultTRPS1 expression was correlated with the patients’ age (P = 0.017). It was positively related with ERα (P < 0.001), progesterone receptor (PR) (P < 0.001) and ERβ (P = 0.001) status, but negatively associated with Ki67 (P = 0.002) and HER2 (P = 0.025) status. In ERα-positive breast cancer, TRPS1 expression was positively associated with the expression of E-cadherin (P < 0.001), β-catenin(P = 0.001), ERβ (P = 0.03), and p53 (P = 0.002) status, while in ERα-negative breast cancer, TRPS1 expression was correlated with slug (P = 0.004), vimentin (P = 0.003), smooth muscle actin (SMA) (P = 0.031), and IMP3 (P = 0.005) expression.ConclusionsBased on our findings, we conclude that TRPS1 is positively associated with E-cadherin and β-catenin status in ERα-positive breast cancer cells, while it is also significantly associated with mesenchymal markers of EMT in ERα-negative breast cancer cells. TRPS1 can be a prognostic marker depending on the type of breast cancer.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8686515681264281

Diagnostic utility and sensitivities of matrix Gla protein (MGP), TRPS1 and GATA3 in breast cancer: focusing on metastatic breast cancer, invasive breast carcinoma with special features, and salivary gland-type tumours

Trichorhinophalangeal syndrome type 1 (TRPS1) is a novel immunohistochemical marker with excellent performance in distinguishing breast carcinoma from other cancers in surgical specimens. The aim of this study was to evaluate the diagnostic utility of TRPS1 compared with GATA3 for metastatic breast carcinoma in effusion cytology specimens. In total, 91 cell blocks of malignant effusion specimens, including 47 metastatic breast carcinomas (nine triple-negative breast carcinomas [TNBCs] and 38 non-TNBCs) and 44 nonmammary malignancies, were selected for TRPS1 and GATA3 immunohistochemistry. Modified H scores ≥ 200 were considered positive staining. The positive rate of TRPS1 was similar between TNBC and non-TNBC (77.8% vs 73.3%, p=.802), whereas the positive rate of GATA3 was lower in TNBC than in non-TNBC (66.7% vs 89.5%, p=.087). The positive rate of TRPS1 was significantly higher in breast carcinoma than in urothelial carcinoma (74.5% vs 0%, p<.001), whereas the positive rate of GATA3 showed no difference between these two (85.1% vs 85.7%, p=.956). Notably, diffuse and strong aberrant expression of TRPS1 was observed in one lung adenocarcinoma and one serous adenocarcinoma in this series. The overall sensitivity, specificity, positive predictive value, and negative predictive value of TRPS1 immunohistochemistry for breast carcinoma were 74.5%, 95.5%, 94.6%, and 77.8%, respectively. TRPS1 is a sensitive and specific marker for metastatic breast cancer in serous effusion cell-block specimens. It shows superior sensitivity and specificity compared with GATA3, especially in the TNBC setting and for excluding urothelial carcinoma.

In evaluating malignant pleural fluid cytology, metastatic adenocarcinomas and mesotheliomas are often differential diagnoses. GATA binding protein 3 (GATA3) has historically been used to confirm metastatic breast carcinomas; however, GATA3 has low specificity if mesothelioma is included in differential diagnoses. Trichorhinophalangeal syndrome type 1 (TRPS1) protein is expressed in all types of breast carcinomas, with reported high specificity and sensitivity. We investigated the performance of TRPS1 immunohistochemistry (IHC) and compared it to GATA3 in pleural fluids diagnosed with metastatic breast carcinoma and mesothelioma. Thirty-six consecutive ThinPrep pleural fluids and 4 pleural fine needle aspirations (FNAs) with diagnoses of metastatic breast carcinoma (21) and mesothelioma (19) were retrieved, and IHC with TRPS1 and GATA3 was performed on all. Immunoreactivity scores for TRPS1 were calculated by multiplying percentage of immunoreactive cells by staining intensity. Immunoreactivity scores were negative if 0 or 1, low positive if 2, intermediate positive if 3 or 4, or high positive if 6 or 9. Nuclear immunoreactivity of ≥10% with at least moderate intensity was judged GATA3 positive. GATA3 showed immunoreactivity in all metastatic breast carcinomas and 84% of mesotheliomas. TRPS1 was immunoreactive in all breast carcinoma cases (18 with a score of 9 and 3 with a score of 6). TRPS1 showed low positivity in 5% of mesothelioma cases with all other cases being negative. When cytomorphologic differential diagnoses of mesothelioma exist, TRPS1 is a more specific marker than GATA3 for confirmation of metastatic breast carcinoma in pleural fluid cytology.

The trichorhinophalangeal syndrome type 1 (TRPS1) immunohistochemical (IHC) stain has increased in use in recent years as a marker for breast carcinomas. The TRPS1 gene is involved in various tissues, including the growth and differentiation of hair follicles. This article seeks to evaluate the IHC expression of TRPS1 in cutaneous neoplasms with follicular differentiation, such as trichoblastoma (TB), trichoepithelioma (TE), and basal cell carcinoma (BCC). IHC studies were performed on 13 TBs, 15 TEs, and 15 BCCs with an antibody against TRPS1. The study found a variable staining expression of TRPS1 in the tumor nests of TB, TE, and BCC. BCCs were distinct in that none of the BCCs demonstrated intermediate or high positivity, while TBs and TEs showed intermediate-to-high positivity in 5/13 (38%) and 3/15 (20%) of cases, respectively. We observed a distinct staining pattern among the mesenchymal cells of TB and TE. We found that TRPS1 highlighted perifollicular mesenchymal cells adjacent to the nests of TB and TE tumor cells. This staining pattern was absent in BCCs, where only scattered stromal cells were positive for TRPS1. Papillary mesenchymal bodies were also highlighted by TRPS1 in TB and TE. TRPS1 stained various parts of the normal hair follicle, including the nuclei of cells in the germinal matrix, outer root sheaths, and hair papillae. TRPS1 may be a useful IHC marker for follicular differentiation.

Trichorhinophalangeal syndrome type 1 (TRPS1) expression in male breast carcinoma

To analyse the diagnostic role of trefoil factor-1 and -3 (TFF1, TFF3), forkhead box protein A1 (FOXA1), carbonic anhydrase XII (CA XII) and trichorhinophalangeal syndrome type 1 (TRPS1) in serous effusions. The prognostic role of these markers in breast carcinoma was additionally studied. Protein expression by immunohistochemistry was analysed in 247 effusions, consisting of 60 breast carcinomas, 54 tubo-ovarian carcinomas, 47 mesotheliomas, 44 lung carcinomas, 20 uterine corpus and cervical carcinomas, 17 gastrointestinal carcinomas and 5 cancers of other origin. TFF1, TFF3, FOXA1, CA XII and TRPS1 expression was found in 67%, 70%, 88%, 82% and 83% of breast carcinomas, respectively. Expression of all markers was seen in some carcinomas of other origin, most commonly in GI metastases, but was least frequent for TRPS1. CA XII expression was additionally seen in mesotheliomas and reactive mesothelial cells. All 5 markers were significantly overexpressed in breast compared to tubo-ovarian carcinoma (all p < 0.001) and lung carcinoma (all p < 0.001 except for FOXA1, p = 0.023). TFF1 (p = 0.003), TFF3 (p = 0.008) and FOXA1 (p = 0.017) expression was significantly higher in receptor-positive compared to receptor-negative primary breast carcinomas. In survival analysis for 44 breast carcinoma patients with clinical data, TFF1 expression was associated with a trend for longer overall (p = 0.096) and disease-free (p = 0.06) survival. TFF1, TFF3, FOXA1, CA XII and TRPS1 are sensitive breast carcinoma markers, with FOXA1 performing best in terms of sensitivity and TRPS1 being the most specific. Whether the expression of these markers in breast carcinoma effusions is informative of survival merits further research.

Definitive diagnosis of metastatic triple-negative breast carcinoma (TNBC) is challenging on cytologic samples. Recent studies demonstrated that trichorhinophalangeal syndrome type 1 (TRPS1) is a highly sensitive and specific marker for diagnosing breast carcinomas, including TNBC, on surgical specimens. To evaluate TRPS1 expression in TNBCs on cytologic samples and a large series of nonbreast tumors on tissue microarray sections. Immunohistochemical (IHC) analysis of TRPS1 and GATA-binding protein 3 (GATA3) was performed on 35 TNBC cases on surgical specimens, and 29 consecutive TNBC cases on cytologic specimens. IHC analysis of TRPS1 expression was also performed on 1079 nonbreast tumors on tissue microarray sections. Of the surgical specimens, 35 of 35 TNBC cases (100%) were positive for TRPS1, all with diffuse positivity, whereas 27 of 35 (77%) were positive for GATA3, with diffuse positivity in 7 cases (26%). Of the cytologic samples, 27 of 29 TNBC cases (93%) were positive for TRPS1, with diffuse positivity in 20 cases (74%), whereas 12 of 29 (41%) were positive for GATA3, with diffuse positivity in 2 cases (17%). Of the nonbreast malignant tumors, TRPS1 expression was seen in 9.4% (3 of 32) of melanomas, 10.7% (3 of 28) of small cell carcinomas of the bladder, and 9.7% (4 of 41) of ovarian serous carcinomas. Our data confirm that TRPS1 is a highly sensitive and specific marker for diagnosing TNBC cases on surgical specimens as reported in the literature. In addition, these data demonstrate that TRPS1 is a much more sensitive marker than GATA3 in detecting metastatic TNBC cases on cytologic samples. Therefore, inclusion of TRPS1 in the diagnostic IHC panel is recommended when a metastatic TNBC is suspected.