Single Cell Analysis of Treatment-Resistant Prostate Cancer: Implications of Cell State Changes for Cell Surface Antigen Targeted Therapies.

Targeting cell surface molecules using radioligand and antibody-based therapies has yielded considerable success across cancers. However, it remains unclear how the expression of putative lineage markers, particularly cell surface molecules, varies in the process of lineage plasticity, wherein tumor cells alter their identity and acquire new oncogenic properties. A notable example of lineage plasticity is the transformation of prostate adenocarcinoma (PRAD) to neuroendocrine prostate cancer (NEPC)--a growing resistance mechanism that results in the loss of responsiveness to androgen blockade and portends dismal patient survival. To understand how lineage markers vary across the evolution of lineage plasticity in prostate cancer, we applied single cell analyses to 21 human prostate tumor biopsies and two genetically engineered mouse models, together with tissue microarray analysis (TMA) on 131 tumor samples. Not only did we observe a higher degree of phenotypic heterogeneity in castrate-resistant PRAD and NEPC than previously anticipated, but also found that the expression of molecules targeted therapeutically, namely PSMA, STEAP1, STEAP2, TROP2, CEACAM5, and DLL3, varied within a subset of gene-regulatory networks (GRNs). We also noted that NEPC and small cell lung cancer (SCLC) subtypes shared a set of GRNs, indicative of conserved biologic pathways that may be exploited therapeutically across tumor types. While this extreme level of transcriptional heterogeneity, particularly in cell surface marker expression, may mitigate the durability of clinical responses to novel antigen-directed therapies, its delineation may yield signatures for patient selection in clinical trials, potentially across distinct cancer types.

Characterization of HOXB13 expression patterns in localized and metastatic castration-resistant prostate cancer.

HOXB13 is a key lineage homeobox transcription factor that plays a critical role in the differentiation of the prostate gland. Several studies have suggested that HOXB13 alterations may be involved in prostate cancer development and progression. Despite its potential biological relevance, little is known about the expression of HOXB13 across the disease spectrum of prostate cancer. To this end, we validated a HOXB13 antibody using genetic controls and investigated HOXB13 protein expression in murine and human developing prostates, localized prostate cancers, and metastatic castration-resistant prostate cancers. We observed that HOXB13 expression increases during later stages of murine prostate development. All localized prostate cancers showed HOXB13 protein expression. Interestingly, lower HOXB13 expression levels were observed in higher-grade tumors, although no significant association between HOXB13 expression and recurrence or disease-specific survival was found. In advanced metastatic prostate cancers, HOXB13 expression was retained in the majority of tumors. While we observed lower levels of HOXB13 protein and mRNA levels in tumors with evidence of lineage plasticity, 84% of androgen receptor-negative castration-resistant prostate cancers and neuroendocrine prostate cancers (NEPCs) retained detectable levels of HOXB13. Notably, the reduced expression observed in NEPCs was associated with a gain of HOXB13 gene body CpG methylation. In comparison to the commonly used prostate lineage marker NKX3.1, HOXB13 showed greater sensitivity in detecting advanced metastatic prostate cancers. Additionally, in a cohort of 837 patients, 383 with prostatic and 454 with non-prostatic tumors, we found that HOXB13 immunohistochemistry had a 97% sensitivity and 99% specificity for prostatic origin. Taken together, our studies provide valuable insight into the expression pattern of HOXB13 during prostate development and cancer progression. Furthermore, our findings support the utility of HOXB13 as a diagnostic biomarker for prostate cancer, particularly to confirm the prostatic origin of advanced metastatic castration-resistant tumors. © 2023 The Pathological Society of Great Britain and Ireland.

Clinical, pathologic, and molecular features of amphicrine prostate cancer.

BACKGROUND: Amphicrine prostate carcinoma (AMPC) is a poorly defined subset of prostate cancer in which cells co-express luminal prostate epithelial and neuroendocrine markers. The optimal treatment strategy is unknown. We sought to further characterize the clinical, histomorphologic, and molecular characteristics of AMPC and to identify areas of potential future treatment investigations. METHODS: We retrospectively identified 17 cases of AMPC at a single institution, defined as synaptophysin expression in >70% of cells and co-expression of androgen receptor (AR) signaling markers (either AR, PSA, or NKX3.1) in >50% of cells. Clinical and histologic features of AMPC cases as well as response to treatment and clinical outcomes were described. RESULTS: Five AMPC cases arose de novo in the absence of prior systemic treatment and behaved distinctly from cases that were treatment-emergent. In these de novo cases, despite expression of neuroendocrine markers, prognosis appeared more favorable than high-grade neuroendocrine carcinoma, with two (40%) patients with de novo metastatic disease, universal response to androgen deprivation therapy, and no deaths at a median follow-up of 12.3 months. Treatment-emergent AMPC arose a median of 41.1 months after androgen deprivation therapy initiation and was associated with poor response to therapy. CONCLUSIONS: We show that amphicrine prostate cancer is a unique entity and differs in clinical and molecular features from high-grade neuroendocrine carcinomas of the prostate. Our study highlights the need to recognize AMPC as a unique molecularly defined subgroup of prostate cancer.

Reversible epigenetic alterations mediate PSMA expression heterogeneity in advanced metastatic prostate cancer.

Prostate-specific membrane antigen (PSMA) is an important cell surface target in prostate cancer. There are limited data on the heterogeneity of PSMA tissue expression in metastatic castration-resistant prostate cancer (mCRPC). Furthermore, the mechanisms regulating PSMA expression (encoded by the FOLH1 gene) are not well understood. Here, we demonstrate that PSMA expression is heterogeneous across different metastatic sites and molecular subtypes of mCRPC. In a rapid autopsy cohort in which multiple metastatic sites per patient were sampled, we found that 13 of 52 (25%) cases had no detectable PSMA and 23 of 52 (44%) cases showed heterogeneous PSMA expression across individual metastases, with 33 (63%) cases harboring at least 1 PSMA-negative site. PSMA-negative tumors displayed distinct transcriptional profiles with expression of druggable targets such as MUC1. Loss of PSMA was associated with epigenetic changes of the FOLH1 locus, including gain of CpG methylation and loss of histone 3 lysine 27 (H3K27) acetylation. Treatment with histone deacetylase (HDAC) inhibitors reversed this epigenetic repression and restored PSMA expression in vitro and in vivo. Collectively, these data provide insights into the expression patterns and regulation of PSMA in mCRPC and suggest that epigenetic therapies - in particular, HDAC inhibitors - can be used to augment PSMA levels.

Genomic Characterization of Prostatic Basal Cell Carcinoma.

Basal cell carcinoma (BCC) of the prostate is a rare tumor. Compared with the more common acinar adenocarcinoma (AAC) of the prostate, BCCs show features of basal cell differentiation and are thought to be biologically distinct from AAC. The spectrum of molecular alterations of BCC has not been comprehensively described, and genomic studies are lacking. Herein, whole genome sequencing was performed on archival formalin-fixed, paraffin-embedded specimens of two cases with BCC. Prostatic BCCs were characterized by an overall low copy number and mutational burden. Recurrent copy number loss of chromosome 16 was observed. In addition, putative driver gene alterations in KIT, DENND3, PTPRU, MGA, and CYLD were identified. Mechanistically, depletion of the CYLD protein resulted in increased proliferation of prostatic basal cells in vitro. Collectively, these studies show that prostatic BCC displays distinct genomic alterations from AAC and highlight a potential role for loss of chromosome 16 in the pathogenesis of this rare tumor type.

ASSESSMENT OF CELL SURFACE TARGETS IN METASTATIC PROSTATE CANCER: EXPRESSION LANDSCAPE AND MOLECULAR CORRELATES.

Therapeutic approaches targeting proteins on the surface of cancer cells have emerged as an important strategy for precision oncology. To fully capitalize on the potential impact of drugs targeting surface proteins, detailed knowledge about the expression patterns of the target proteins in tumor tissues is required. In castration-resistant prostate cancer (CRPC), agents targeting prostate-specific membrane antigen (PSMA) have demonstrated clinical activity. However, PSMA expression is lost in a significant number of CRPC tumors, and the identification of additional cell surface targets is necessary in order to develop new therapeutic approaches. Here, we performed a comprehensive analysis of the expression and co-expression patterns of trophoblast cell-surface antigen 2 (TROP2), delta-like ligand 3 (DLL3), and carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) in CRPC samples from a rapid autopsy cohort. We show that DLL3 and CEACAM5 exhibit the highest expression in neuroendocrine prostate cancer (NEPC), while TROP2 is expressed across different CRPC molecular subtypes, except for NEPC. We observed variable intra-tumoral and inter-tumoral heterogeneity and no dominant metastatic site predilections for TROP2, DLL3, and CEACAM5. We further show that AR amplifications were associated with higher expression of PSMA and TROP2 but lower DLL3 and CEACAM5 levels. Conversely, PSMA and TROP2 expression was lower in RB1-altered tumors. In addition to genomic alterations, we demonstrate a tight correlation between epigenetic states, particularly histone H3 lysine 27 methylation (H3K27me3) at the transcriptional start site and gene body of TACSTD2 (encoding TROP2), DLL3, and CEACAM5, and their respective protein expression in CRPC patient-derived xenografts. Collectively, these findings provide novel insights into the patterns and determinants of expression of TROP2, DLL3, and CEACAM5 with important implications for the clinical development of cell surface targeting agents in CRPC.

Clonal relationships of adjacent Gleason pattern 3 and Gleason pattern 5 lesions in Gleason Scores 3+5=8 and 5+3=8.

Genomic studies have demonstrated a high level of intra-tumoral heterogeneity in prostate cancer. There is strong evidence suggesting that individual tumor foci can arise as genetically distinct, clonally independent lesions. However, recent studies have also demonstrated that adjacent Gleason pattern (GP) 3 and GP4 lesions can originate from the same clone but follow divergent genetic and morphologic evolution. The clonal relationship of adjacent GP3 and GP5 lesions has thus far not been investigated. Here we analyzed a cohort of 14 cases-11 biopsy and 3 radical prostatectomy specimens-with a Gleason score of 3 + 5 = 8 or 5 + 3 = 8 present in the same biopsy or in a single dominant tumor nodule at radical prostatectomy. Clonal and subclonal relationships between GP3 and GP5 lesions were assessed using genetically validated immunohistochemical assays for ERG, PTEN, and P53. 9/14 (64%) cases showed ERG reactivity in both GP3 and GP5 lesions. Only 1/14 (7%) cases showed a discordant pattern with ERG staining present only in GP3. PTEN expression was lost in 2/14 (14%) cases with perfect concordance between GP5 and GP3. P53 nuclear reactivity was present in 1/14 (7%) case in both GP5 and GP3. This study provides first evidence that the majority of adjacent GP3 and GP5 lesions share driver alterations and are clonally related. In addition, we observed a lower-than-expected rate of PTEN loss in GP5 in the context of Gleason score 3 + 5 = 8 or 5 + 3 = 8 tumors.

Therapeutic Implications for Intrinsic Phenotype Classification of Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: To determine whether metastatic castration-resistant prostate cancers (mCRPC) partition into molecular phenotypes corresponding to intrinsic differentiation states and ascertain whether these subtypes exhibit specific druggable features and associate with treatment outcomes. EXPERIMENTAL DESIGN: We used RNAseq, digital spatial profiling, and histological assessments from metastatic biopsies and patient-derived xenografts to segregate mCRPCs into subtypes defined by the PAM50 breast cancer classification algorithm. Subtype associations with treatment responses in preclinical models and patients were determined. RESULTS: Using the PAM50 algorithm, we partitioned 270 mCRPC tumors into LumA (42%), LumB (24%), and Basal (34%) subtypes with classification largely driven by proliferation rates and androgen receptor (AR) activity. Most neuroendocrine tumors classified as Basal. Pathways enriched in the LumA subtype include TGFß and NOTCH signaling. LumB subtype tumors were notable for elevated MYC activity. Basal subtype tumors exhibited elevated IL6-STAT3 signaling and features of adult stem cell states. In patients where multiple tumors were evaluated, the majority had concordant PAM50 subtype determination, though a subset exhibited marked inter- and intratumor heterogeneity, including divergent classifications between primary and metastatic sites. In preclinical models, LumA subtype tumors were highly responsive to androgen deprivation and docetaxel chemotherapy whereas Basal tumors were largely resistant. In clinical cohorts patients with Basal subtype tumors demonstrated a shorter time on treatment with AR signaling inhibitors and docetaxel relative to patients with luminal subtypes. CONCLUSIONS: Subtyping of mCRPC based on cell differentiation states has potential clinical utility for identifying patients with divergent expression of treatment targets and responses to systemic therapy.

Does evaluation of tumor volume or/both origination site better guide to optimal surgery for inverted papilloma? / A avaliação do volume do tumor e/ou dos seus locais de origem fornece a melhor orientação para a técnica cirúrgica ideal do papiloma invertido?

Abstract Introduction Sinonasal inverted papilloma is noted for its high rate of recurrence. Staging systems aid to reduce recurrence and avoid excessive surgeries by guiding the selection of the optimal surgical approach. Objective To evaluate the effectiveness of different endoscopic approaches in inverted papilloma by assessing tumor origin site and tumor volume. Methods Krouse classification system that is based on tumor volume was used for staging; furthermore, tumor origin sites were grouped as lateral nasal wall, medial wall and other walls of maxillary sinus. The main treatment method for all patients was endoscopic sinus surgery. Endoscopic extended middle meatal antrostomy, endoscopic Caldwell-Luc and endoscopic medial maxillectomy were the additional surgery types performed in different combinations. Results Fifty-five patients (42 male) with a mean 54.9 ± 14.4 years of age were included. 37 patients were diagnosed with advanced stage inverted papilloma (67.2 %). Recurrence was observed in 12 patients (21.8 %). In early stage lateral nasal wall origination, no recurrence was observed in the simple tumor resection group (0/10). In early stage medial wall origination, no recurrence was observed in the extended middle meatal antrostomy group (0/8). In advanced stage medial wall origination, the recurrence rates of extended middle meatal antrostomy, extended middle meatal antrostomy + endoscopic Caldwell- Luc and endoscopic medial maxillectomy were 100.0 %, 53.8 % and 13.6 %, respectively (p = 0.002). In advanced stage other walls of maxillary sinus origination, recurrence rates of extended middle meatal antrostomy + endoscopic Caldwell-Luc and endoscopic medial maxillectomy were 20 % and 16.6 %, respectively (p = 0.887). Conclusion Tumor origin site, tumor stage and surgery types show an impact on recurrence. Despite the fact that tumor origin site singly could lead to appropriate selection of the surgery type in most cases, tumor stage carries substantial importance in selection of surgery type for sinonasal-inverted papilloma. An operation plan regarding both tumor volume and tumor origin site may aid surgeons in selecting optimal endoscopic surgical method to avoid recurrence or excessive surgeries.

Resumo Introdução O papiloma invertido nasossinusal é conhecido por sua alta taxa de recorrência. Os sistemas de estadiamento ajudam a reduzir a recorrência e evitar cirurgias excessivas e orientam a seleção da abordagem cirúrgica ideal. Objetivo Avaliar a eficácia de diferentes abordagens endoscópicas no papiloma invertido, de acordo com o local de origem e o volume do tumor. Método Para o estadiamento, usou-se o sistema de classificação de Krouse, baseado no volume do tumor; além disso, os tumores foram agrupados de acordo com seus locais de origem: parede nasal lateral, parede medial e outras paredes do seio maxilar. O principal método de tratamento para todos os pacientes foi a cirurgia endoscópica nasossinusal. Foram feitos, em diferentes combinações, os seguintes tipos de cirurgia: antrostomia estendida do meato médio, Caldwell-Luc endoscópica e maxilectomia medial endoscópica. Resultados Foram incluídos 55 pacientes (42 homens) com média de 54,9 ± 14,4 anos. Trinta e sete pacientes foram diagnosticados com papiloma invertido avançado (67,2%). Foi observada recorrência em 12 pacientes (21,8%). No estágio inicial com origem na parede nasal lateral, não foi observada recorrência no grupo de ressecção simples de tumor (0/10). No estágio inicial com origem na parede medial, não foi observada recorrência no grupo de antrostomia estendida do meato médio (0/8). Com tumor em estágio avançado com origem na parede medial, as taxas de recorrência na antrostomia estendida do meato médio, antrostomia estendida do meato médio + Caldwell-Luc endoscópica e maxilectomia medial endoscópica foram de 100,0%, 53,8% e 13,6%, respectivamente (p = 0,002). No tumor em estágio avançado em outras paredes do seio maxilar, as taxas de recorrência na antrostomia estendida do meato médio + Caldwell-Luc endoscópica e maxilectomia medial endoscópica foram de 20% e 16,6%, respectivamente (p = 0,887). Conclusão O local de origem do tumor, o estágio do tumor e os tipos de cirurgia mostram impacto na recorrência. Apesar da consideração de que na maioria dos casos o local de origem do tumor pode, de forma isolada, orientar a seleção apropriada do tipo de cirurgia, o estágio do tumor tem importância substancial na seleção do tipo de cirurgia para papiloma invertido nasossinusal. Um planejamento cirúrgico considerando tanto o volume quanto o local de origem do tumor pode ajudar os cirurgiões a selecionar o tipo ideal de cirurgia endoscópica para evitar recorrências ou remoções excessivas.

Does evaluation of tumor volume or/both origination site better guide to optimal surgery for inverted papilloma?

INTRODUCTION: Sinonasal inverted papilloma is noted for its high rate of recurrence. Staging systems aid to reduce recurrence and avoid excessive surgeries by guiding the selection of the optimal surgical approach. OBJECTIVE: To evaluate the effectiveness of different endoscopic approaches in inverted papilloma by assessing tumor origin site and tumor volume. METHODS: Krouse classification system that is based on tumor volume was used for staging; furthermore, tumor origin sites were grouped as lateral nasal wall, medial wall and other walls of maxillary sinus. The main treatment method for all patients was endoscopic sinus surgery. Endoscopic extended middle meatal antrostomy, endoscopic Caldwell-Luc and endoscopic medial maxillectomy were the additional surgery types performed in different combinations. RESULTS: Fifty-five patients (42 male) with a mean 54.9±14.4 years of age were included. 37 patients were diagnosed with advanced stage inverted papilloma (67.2 %). Recurrence was observed in 12 patients (21.8 %). In early stage lateral nasal wall origination, no recurrence was observed in the simple tumor resection group (0/10). In early stage medial wall origination, no recurrence was observed in the extended middle meatal antrostomy group (0/8). In advanced stage medial wall origination, the recurrence rates of extended middle meatal antrostomy, extended middle meatal antrostomy+endoscopic Caldwell- Luc and endoscopic medial maxillectomy were 100.0 %, 53.8 % and 13.6 %, respectively (p=0.002). In advanced stage other walls of maxillary sinus origination, recurrence rates of extended middle meatal antrostomy+endoscopic Caldwell-Luc and endoscopic medial maxillectomy were 20 % and 16.6 %, respectively (p=0.887). CONCLUSION: Tumor origin site, tumor stage and surgery types show an impact on recurrence. Despite the fact that tumor origin site singly could lead to appropriate selection of the surgery type in most cases, tumor stage carries substantial importance in selection of surgery type for sinonasal-inverted papilloma. An operation plan regarding both tumor volume and tumor origin site may aid surgeons in selecting optimal endoscopic surgical method to avoid recurrence or excessive surgeries.

Submandibular gland cancers: prognostic factors and survival analysis.

PURPOSE: The aim of this study is to evaluate prognosis and prognostic factors affecting oncological outcome. METHODS: Records of the subjects managed for a submandibular gland cancer (SGC) between January 1997 and June 2014 were retrospectively reviewed. Survival outcomes were analyzed. All subjects had a minimum follow up of 5 years or until death. RESULTS: Of 24 subjects (13 male, 11 female), 16 (64.6%) were adenoid cystic carcinoma (ACC). Eight patients had clinically positive neck nodes and 2 of the 16 clinically negative necks were also positive histologically. None of the subjects had distant metastases at presentation. The Kaplan-Meier 5-year estimated locoregional control (LRC), distant metastasis free survival (DMFS), disease free survival (DFS) and overall survival (OS) were 62.5%, 83.3%, 58.3% and 66.7%, respectively. American Joint Committee on Cancer (AJCC) overall stage and extra glandular extension (EGE) proved to be significant predictors of LRC. Only smoking was found to be a significant factor related with lower DMFS and only EGE significantly lowered DFS. Positive nodal stage and positive surgical margin were proved to be significant predictors of OS. CONCLUSION: Surgery alone is effective in subjects with early stage, noninvasive and low-grade cancers. Despite aggressive treatment, locoregional recurrence was common in subjects who were at advanced stage.

[Nasal type natural killer/T cell lymphoma: case series and literature review]. / Nazal tip dogal katil/T hücreli lenfoma: Olgu serisi ve literatür derlemesi.

Nasal type natural killer/T-cell lymphoma is a rare type of extranodal non-Hodgkin lymphoma which originates from nasal cavity and paranasal sinuses. Exact diagnosis of nasal natural killer/T-cell lymphoma, which is a rapidly progressive clinical condition, may be established by immunohistochemical analysis on biopsy material after clinical suspicion. In this article, we report four cases of nasal natural killer/T-cell lymphoma who were followed-up in our clinic and discuss the diagnosis and treatment of the disease in light of the literature data.