Sensitivity of HOXB13 as a Diagnostic Immunohistochemical Marker of Prostatic Origin in Prostate Cancer Metastases: Comparison to PSA, Prostein, Androgen Receptor, ERG, NKX3.1, PSAP, and PSMA

Prostein expression on circulating tumor cells as a prognostic marker in metastatic castration-resistant prostate cancer

BACKGROUND

Identification of emerging molecular biomarkers on circulating tumor cells (CTCs) represents an attractive feature of liquid biopsy that facilitates precision and tailored medicine in the management of metastatic castration-resistant prostate cancer (mCRPC). Prostein is an androgen-regulated transmembrane protein with high prostate specificity. Prostein-positive circulating tumor cell (CTC) was recently suggested to have diagnostic potential; however, no study has been conducted to evaluate its prognostic value in mCRPC.

METHODS

CTCs from mCRPC patients were enumerated using the CellSearch System. Prostein-positive CTCs were identified by immunostaining results. The relationships between prostein expression on CTCs and PSA response rate, PSA progression-free survival (PSA-PFS), radiographic progression-free survival (PFS), and overall survival (OS) were tested by Fisher's exact test or evaluated using Kaplan-Meier and multivariate Cox analyses.

RESULTS

Prostein-positive CTCs were identified in 31 of 87 baseline samples from mCRPC patients and 16 of 51 samples collected at the first follow-up visit. PSA response rates were significantly lower in baseline prostein-positive patients (0%, 0/31) than in prostein-negative patients (19.6%, 11/56) (p = 0.007). The 31 prostein-positive patients had significantly shorter PSA-PFS (p < 0.001), radiographic PFS (p < 0.001), and OS (p = 0.018), compared to the 56 prostein-negative patients at baseline. The association with PSA-PFS maintained its significance (p = 0.028) in multivariate analyses. Analyzing prostein expression at the first follow-up as well as the conversion of prostein expression from baseline to follow-up samples not only confirmed the association with PSA-PFS, but also demonstrated prognostic significance with OS.

CONCLUSION

Our study provides the first evidence to support the potential of prostein expression on CTCs to serve as a novel prognostic marker in mCRPC patients. Future large-scale prospective studies are needed to validate our findings.

Prostate Adenocarcinoma with Signet-Ring Cells and Features of Mucin: A Clinical Case and Literature Review

Introduction: Signet-ring cells are typically associated with mucin-secreting epithelium; thus, they are most commonly found in the gastrointestinal tract, but not exclusively. Primary signet-ring cell carcinoma of the prostate is a rare and poorly differentiated, aggressive acinar adenocarcinoma variant with a grim prognosis. Clinical Case: In June of 2023, a 54-year-old Caucasian male presented with a complaint of lower urinary tract obstructive symptoms with occasional macrohematuria, non-specific body aches, and shortness of breath. A prostate specimen obtained in transurethral resection of the prostate was sent for histopathological examination. After a series of extraprostatic diagnostic workups, including fibrogastroduodenoscopy, colonoscopy computed tomography imaging, and immunohistochemical studies, the patient was diagnosed with primary prostatic signet-ring cell adenocarcinoma stage IV. Unfortunately, due to the advanced stage of the disease, PE, and third-degree thrombocytopenia, the patient was not a candidate for chemotherapy and died of cardiopulmonary insufficiency later that week. Discussion: Prostatic signet-ring cell carcinoma accounts for 0.02% of all prostate adenocarcinoma cases. Due to its nature and epidemiology, a diligent extraprostatic investigation has to be carried out. The disease often presents with unremarkable clinical symptoms and variable serum prostate-specific antigen results, which may contribute to its late diagnosis. Inconsistent immunohistochemical findings and an unpredictable response to hormonal treatment together pose both diagnostic and therapeutic challenges that negatively affect the prognosis. Conclusions: This study highlights the importance of a multidisciplinary approach and the need for diagnostic and therapeutic consensus within the research community in search of the primary site of the disease, which may positively influence the prognosis.

Upcycling HOXB13: enhancing prostate cancer detection with a novel antibody†

Prostate cancer is one of the most prevalent and, upon metastasis, deadliest cancers in men. Timely identification is essential for effective treatment. Furthermore, accurate determination of prostatic origin is crucial for personalized therapy once the cancer has spread. However, current prostate cancer screening methods are lacking. A recent article in The Journal of Pathology addresses this issue by utilizing an improved antibody to reevaluate HOXB13 as a lineage marker for prostate cancer. The study's findings support the concept that, despite decreased expression in advanced prostate cancer, HOXB13 remains highly suitable for determining prostatic origin due to its androgen receptor independence, high specificity, and sensitivity. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

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.

Role of intraoperative touch imprint cytology and immunohistochemistry in the diagnosis of metastatic malignancies in the central nervous system: Cyto-histomorphological findings and differential diagnosis

BACKGROUND

Brain metastases (BMs) are intracranial neoplasms that are more common in adults than primary brain tumors, causing significant mortality and morbidity in cancer patients. This study aimed to evaluate the definitive histopathological diagnosis using touch imprint cytology and the importance and use of immunohistochemistry in the diagnosis of primary origin.

METHOD

Cytological, paraffin section, and immunohistochemical study slides of all metastatic brain tumors consecutively consulted at the pathology department between 2018 and 2023 were evaluated. The sensitivity, specificity, and accuracy of patients' diagnostic results who underwent imprint cytology were compared based on the final diagnosis histopathological report.

RESULTS

A total of 45 patients with and without intraoperative consultation were included in the study. The definitive histopathologic diagnosis and the diagnostic accuracy rate of imprint cytology for distinguishing glial and metastatic tumors on paraffin sections was 100%. Immunohistochemistry was performed in all patients (except one patient; immediate exitus) and histological classification of the primary tumor was performed by analysis of clinical findings and biomarkers. The primary origins of metastatic tumors were often lung and breast, with adenocarcinoma subtype histomorphology, cerebral hemispheres, and discrete foci of metastasis.

CONCLUSION

TPs is a simple and rapid technique that supports diagnosis in intraoperative neuropathology and is a very cost-effective procedure. The pathologist's experience is the key factor in the diagnosis and reduces the need for a frozen section. In our series, the final histopathologic correlation of imprint cytology in the diagnosis of primary and metastatic tumors is 100%.

Differential Protein Expression Patterns of HOXA13 and HOXB13 Are Associated with Bladder Cancer Progression

Bladder cancer is a common urological cancer and has the highest recurrence rate of any cancer. The aim of our study was to profile and characterize the protein expression of homeobox A13 (HOXA13) and homeobox B13 (HOXB13) genes in Malaysian bladder cancer patients. The protein expression of HOXA13 and HOXB13 in formalin-fixed paraffin-embedded (FFPE) bladder cancer tissues was determined by immunohistochemistry (IHC) analysis. The association between HOXA13/HOXB13 protein expression and demographic/clinicopathological characteristics of the bladder cancer patients was determined by chi-square analysis. Approximately 63.6% of the bladder cancer tissues harbored high HOXA13 expression. High HOXA13 expression was significantly associated with non-muscle invasive bladder cancer, lower tumor grade, higher number of lymph node metastases, and recurrence risk. In contrast, low HOXB13 expression (including those with negative expression) was observed in 71.6% of the bladder cancer tissues analyzed. Low HOXB13 expression was significantly associated with muscle-invasive bladder cancer, higher tumor stage, tumor grade, and metastatic risk. Both HOXA13 and HOXB13 protein expression were found to be associated with bladder tumorigenesis. The putative oncogenic and tumor suppressive roles of HOXA13 and HOXB13, respectively, suggest their potential utility as biomarkers in bladder cancer.

Histopathological Aspects of the Prognostic Factors for Salivary Gland Cancers

Salivary gland cancers (SGCs) are diagnosed using histopathological examination, which significantly contributes to their progression, including lymph node/distant metastasis or local recurrence. In the current World Health Organization (WHO) Classification of Head and Neck Tumors: Salivary Glands (5th edition), malignant and benign epithelial tumors are classified into 21 and 15 tumor types, respectively. All malignant tumors have the potential for lymph node/distant metastasis or local recurrence. In particular, mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (AdCC), salivary duct carcinoma, salivary carcinoma, not otherwise specified (NOS, formerly known as adenocarcinoma, NOS), myoepithelial carcinoma, epithelial-myoepithelial carcinoma, and carcinoma ex pleomorphic adenoma (PA) are relatively prevalent. High-grade transformation is an important aspect of tumor progression in SGCs. MEC, AdCC, salivary carcinoma, and NOS have a distinct grading system; however, a universal histological grading system for SGCs has not yet been recommended. Conversely, PA is considered benign; nonetheless, it should be cautiously treated to avoid the development of metastasizing/recurrent PA. The aim of this review is to describe the current histopathological aspects of the prognostic factors for SGCs and discuss the genes or molecules used as diagnostic tools that might have treatment target potential in the future.

Tissue immunostaining of candidate prognostic proteins in metastatic and non-metastatic prostate cancer

PURPOSE

Prostate cancer (PCa) lacks specific markers capable of distinguishing aggressive tumors from those with indolent behavior. Therefore, the aim of this study was to evaluate the immunostaining of candidate proteins (PTEN, AKT, TRPM8, and NKX3.1) through the immunohistochemistry technique (IHC) on patients with metastatic and non-metastatic PCa.

METHODS

Tissues from 60 patients were divided into three groups categorized according to prognostic parameters: better prognosis (n = 20), worse prognosis (n = 23), and metastatic (n = 17). Immunostaining was analyzed by a pathologist and staining classifications were considered according to signal intensity: (0) no staining, (+) weak, and (++ and +++) intermediate to strong.

RESULTS

AKT protein was associated (p = 0.012) and correlated (p = 0.014; Tau = - 0.288) with the prognostic groups. The immunostaining for TRPM8 (p = 0.010) and NKX3.1 (p = 0.003) proteins differed between malignant tumor and non-tumoral adjacent tissue as well as for proteins in cellular locations (nucleus and cytoplasm). TRPM8 was independently associated with the ISUP grade ≥ 4 (p = 0.024; OR = 8.373; 95% CI = 1.319-53.164). The NKX3.1 showed positive and predominantly strong immunostaining in all patients in both tumoral and non-tumoral adjacent tissues. All metastatic samples had positive immunostaining, with strong intensity for NKX3.1 (p = 0.021; Tau = - 0.302). In the non-metastatic group, this strong protein staining was not observed in any patients.

CONCLUSION

This study confirmed that NKX3.1 is highly specific for prostate tissue and indicated that NKX3.1, AKT, and TRPM8 may be candidate markers for prostate cancer prognosis.

The prostate in women: an updated histological and immunohistochemical profile of the female periurethral glands and their relationship to an implanted midurethral sling

BACKGROUND

There is evidence of glandular tissue in the region of the anterior vaginal wall-female periurethral tissue (AVW-FPT) that has similar morphology and immunohistochemistry to the prostate in men. Surgical injury to this tissue has been suggested as a potential cause of sexual dysfunction following midurethral sling (MUS) procedures. However, the anatomy and embryology of these glands have not been fully resolved. This has led to difficulties in classifying this tissue as a prostate and defining its clinical significance related to MUS procedures.

AIM

To describe the histological and immunohistochemical characteristics of the female periurethral glands using markers of prostate tissue and innervation and to examine their anatomical relationships to an implanted MUS.

METHODS

Using gross and fine dissection, the AVW-FPT was dissected from 9 cadavers. Prior to dissection, 2 cadavers underwent simulation of the MUS procedure by a urogynecologist. Samples were paraffin embedded and serially sectioned. Immunohistochemistry was performed using markers of prostate tissue and innervation.

OUTCOMES

Redundant immunohistochemical localization of markers for prostatic tissue and innervation of the glandular tissue of the AVW-FPT, including the region of MUS implantation.

RESULTS

Female periurethral glands were immunoreactive for markers of male prostatic tissue, including prostate-specific antigen, androgen receptor, HOXB13, and NKX3.1. Markers of innervation (protein gene product 9.5, choline acetyl transferase, and vasoactive intestinal polypeptide) also localized to certain regions of the glandular tissue and associated blood supply. Surgical simulation of the MUS procedure demonstrated that some periurethral glands are located in close proximity to an implanted sling.

CLINICAL TRANSLATION

The AVW-FPT contains glandular tissue in the surgical field of MUS implantation. Iatrogenic damage to the female periurethral glands and the associated innervation during surgery could explain the negative impacts on sexual dysfunction reported following MUS procedures.

STRENGTHS AND LIMITATIONS

This is the first study to characterize the female periurethral glands using markers of prostatic tissue in concert with markers of general and autonomic innervation and characterize their anatomical relationships within the surgical field of MUS implantation. The small sample size is a limitation of this study.

CONCLUSION

We provide further evidence that the AVW-FPT contains innervated glands that are phenotypically similar to the male prostate and may share a common embryonic origin. The microscopic and immunohistochemical features of the periurethral glands may be indicative of their functional capacity in sexual responses. The location of these glands in the surgical field of MUS procedures underscores the clinical significance of this tissue.

Diagnostic pitfalls: a case of prostate cancer and rectal cancer accompanied by prostate cancer invasion of the rectum

INTRODUCTION

Case of double primary cancer of the prostate and rectum is rare, prostate cancer involving the postoperative intestinal anastomotic mucosal tissue is even rarer.

CASE PRESENTATION

We report a case of rectal cancer discovered 1 year after a diagnosis of prostate cancer and a tumour in the postoperative anastomotic intestinal mucosal tissue involving prostatic adenocarcinoma at 1 year after the diagnosis of rectal cancer. Due to the poor differentiation of both prostate and rectal cancers, there are some pitfalls in the diagnosis of intestinal mucosal lesions at an anastomosis. The lack of an accurate diagnosis of a tumour in anastomosis intestinal mucosal tissue will affect treatment and patient survival.

CONCLUSIONS

The pathologists should have a detailed understanding of the patient's medical history and carefully observe the histopathological morphology and, if necessary, immunohistochemistry or other techniques should be used to assist in the pathological diagnosis and avoid both misdiagnosis and missed diagnosis.

Should We Call It a Prostate? A Review of the Female Periurethral Glandular Tissue Morphology, Histochemistry, Nomenclature, and Role in Iatrogenic Sexual Dysfunction

INTRODUCTION

There is evidence of glandular tissue within the region of the anterior vaginal wall-female periurethral tissue (AVW-FPT) having similar morphology and immunohistochemistry to the prostate in men and having physiological roles in the female sexual response (FSR). Whether this tissue should be called a prostate in women has been debated. Iatrogenic injury to structures of the AVW-FPT, including these glands and the associated neurovasculature, could be a cause of female sexual dysfunction (FSD).

OBJECTIVES

To consolidate the current knowledge concerning the glandular tissue surrounding the urethra in women, evidence was reviewed to address whether: (i) these glands comprise the prostate in women, (ii) they have specific functions in the FSR, and (iii) injury to the AVW-FPT and prostate has sexual dysfunction as a likely outcome.

METHODS

A literature review was conducted using keywords including female prostate, Skene's/paraurethral glands, periurethral tissue, Gräfenberg (G)-spot, female ejaculation, mid-urethral sling (MUS), and sexual dysfunction.

RESULTS

Histological and immunohistochemical studies of the glandular tissue surrounding the urethra support the existence of prostate in women. Evidence suggests this tissue may have physiologically and clinically relevant autonomic and sensory innervation, and during sexual arousal may contribute to secretions involved in ejaculation and orgasm. Gaps in knowledge relating to the functional anatomy, physiological roles, and embryological origins of this tissue have impeded the acceptance of a prostate in women. Injury to the innervation, vasculature, and/or glandular tissue within the surgical field of MUS implantation suggests iatrogenic sexual dysfunction is plausible.

CONCLUSIONS

Continuing to advance our understanding of the morphology, histochemistry, and physiologic capacity of this glandular tissue will clarify the characterization of this tissue as the "prostate" involved in the FSR, and its role in FSD following surgical injury. Tomalty D, Giovannetti O, Hannan J, et al. Should We Call It a Prostate? A Review of the Female Periurethral Glandular Tissue Morphology, Histochemistry, Nomenclature, and Role in Iatrogenic Sexual Dysfunction. Sex Med Rev 2021;XX:XXX-XXX.

Expression of NKX3.1, Prostatic Specific Antigen and Prostatic Specific Alkaline Phosphatase in Cytology Specimens of Metastatic Prostatic Carcinoma

Background and objectives

NKX3.1 is an emerging marker for tumors of prostatic origin; however, the utility and diagnostic values of NKX3.1 have not been broadly studied in cytology specimens. The purpose of this study is to determine the performance of NKX3.1, compared to prostatic specific antigen (PSA) and prostatic specific alkaline phosphatase (PSAP), as an organ-specific marker of metastatic prostatic adenocarcinoma (MPAC) in cytology specimens.

Methods

The cytology specimens, which had been evaluated to include or exclude MPAC, were collected from our pathology database. Immunostains for PSA, PSAP, and NKX3.1 were performed on cell block sections.

Results

A total of 118 cases were collected. In 37 MPACs, NKX3.1 was diffusely positive in 34 cases (92%) and focally positive in 3 cases (8%). PSA indicated diffuse positivity in 16 cases (43%), focal positivity in 13 (35%) cases, and was negative in 8 (22%) cases. PSAP immunostain was performed in only 12 MPACs, showing diffuse positivity in 5 (42%), focal positivity in 3 (25%), and negativity in 4 (33%) cases. Among the 81 non-metastatic prostatic adenocarcinoma cases, NKX3.1 was negative in 80 (99%) cases and focally positive in only 1 (1%) case; all cases with available PSA and PSAP staining were negative. The calculated sensitivities for NKX3.1, PSA, and PSAP were 100%, 78%, and 67%, respectively, while the specificities were 99%, 100%, and 100%, respectively.

Conclusions

Compared to PSA and PSAP, NKX3.1 is more reliable as an individual marker for MPAC in cytology specimens. Combining NKX3.1 and PSA can be useful in some cases to enhance diagnostic utility.

Delineating the Molecular Events Underlying Development of Prostate Cancer Variants with Neuroendocrine/Small Cell Carcinoma Characteristics

The treatment landscape of prostate cancer has changed dramatically following the advent of novel systemic therapies, most of which target the androgen receptor (AR). Agents such as abiraterone, enzalutamide, apalutamide, darolutamide were designed to further suppress androgen receptor signaling following gonadal suppression achieved by first-line androgen deprivation therapies. These potent AR targeting agents are increasingly used in the earlier stages of the disease spectrum with the goal of delaying disease progression and extending survival. Although these therapies are effective in controlling prostate tumors dependent on or addicted to AR signaling, prostate tumors surviving the onslaught of potent treatments may evolve and develop drug resistance. A substantial proportion of treatment failures can be explained by the development of treatment-induced aggressive prostate cancer variants such as neuroendocrine/small cell carcinoma. These emerging disease entities demand detailed characterization and precise definitions. We postulate that these treatment-induced prostate cancer entities should be defined molecularly to overcome the drawbacks associated with the current clinical and pathological definitions. A precise molecular definition conforms with current knowledge on the molecular evolution of this disease entity and will enable early detection and early intervention.

An RNA-Seq-Based Framework for Characterizing Canine Prostate Cancer and Prioritizing Clinically Relevant Biomarker Candidate Genes

Prostate cancer (PCa) in dogs is a highly malignant disease akin to its human counterpart. In contrast to the situation in humans, multi-gene approaches facilitating risk stratification of canine PCa are barely established. The aims of this study were the characterization of the transcriptional landscape of canine PCa and the identification of diagnostic, prognostic and/or therapeutic biomarkers through a multi-step screening approach. RNA-Sequencing of ten malignant tissues and fine-needle aspirations (FNA), and 14 nonmalignant tissues and FNAs was performed to find differentially expressed genes (DEGs) and deregulated pathways. The 4098 observed DEGs were involved in 49 pathways. These 49 pathways could be grouped into five superpathways summarizing the hallmarks of canine PCa: (i) inflammatory response and cytokines; (ii) regulation of the immune system and cell death; (iii) cell surface and PI3K signaling; (iv) cell cycle; and (v) phagosome and autophagy. Among the highly deregulated, moderately to strongly expressed DEGs that were members of one or more superpathways, 169 DEGs were listed in relevant databases and/or the literature and included members of the PCa pathway, oncogenes, prostate-specific genes, and druggable genes. These genes are novel and promising candidate diagnostic, prognostic and/or therapeutic canine PCa biomarkers.

Distinguishing Rectal Cancer from Colon Cancer Based on the Support Vector Machine Method and RNA-sequencing Data

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. Several studies have indicated that rectal cancer is significantly different from colon cancer in terms of treatment, prognosis, and metastasis. Recently, the differential mRNA expression of colon cancer and rectal cancer has received a great deal of attention. The current study aimed to identify significant differences between colon cancer and rectal cancer based on RNA sequencing (RNA-seq) data via support vector machines (SVM). Here, 393 CRC samples from the The Cancer Genome Atlas (TCGA) database were investigated, including 298 patients with colon cancer and 95 with rectal cancer. Following the random forest (RF) analysis of the mRNA expression data, 96 genes such as HOXB13, PRAC, and BCLAF1 were identified and utilized to build the SVM classification model with the Leave-One-Out Cross-validation (LOOCV) algorithm. In the training (n=196) and the validation cohorts (n=197), the accuracy (82.1 % and 82.2 %, respectively) and the AUC (0.87 and 0.91, respectively) indicated that the established optimal SVM classification model distinguished colon cancer from rectal cancer reasonably. However, additional experiments are required to validate the predicted gene expression levels and functions.

The International System for Reporting Serous Fluid Cytopathology: How to Incorporate Molecular Data in Cytopathology Reports

Serous effusion cytology is widely employed in the initial evaluation of the etiology of effusions with a high diagnostic sensitivity. To standardize practices, The International System for Reporting Serous Fluid Cytology (TIS) was developed following best international practices, the most up-to-date literature, and expert consensus. In the context of this system, ancillary techniques play an important role. Besides defining basic principles in laboratory specimen handling, adequacy criteria, and a standardized reporting terminology with five diagnostic categories, TIS provides an actionable framework for using immunohistochemical and molecular testing in effusion samples, namely, in atypical, suspicious of malignant samples. For diagnostic purposes, these tests may be employed to distinguish between a primary and secondary neoplasm, to confirm a diagnosis of malignant mesothelioma vs. reactive mesothelial hyperplasia, and to correctly classify and determine the primary location of a metastasis. Theranostic molecular tests may also be used for these samples to evaluate potential therapeutic targets. Pathologists play a central role in guiding this process by determining adequacy and selecting appropriate ancillary tests. The activity in this area of research should increase in the near future as new therapeutic targets are discovered and new drugs enter the clinical practice.

Multiple roles of HOX proteins in Metastasis: Let me count the ways

Knowledge of the role of HOX proteins in cancer has been steadily accumulating in the last 25 years. They are encoded by 39 HOX genes arranged in 4 distinct clusters, and have unique and redundant function in all types of cancers. Many HOX genes behave as oncogenic transcriptional factors regulating multiple pathways that are critical to malignant progression in a variety of tumors. Some HOX proteins have dual roles that are tumor-site specific, displaying both oncogenic and tumor suppressor function. The focus of this review is on how HOX proteins contribute to growth or suppression of metastasis. The review will cover HOX protein function in the critical aspects of epithelial-mesenchymal transition, in cancer stem cell sustenance and in therapy resistance, manifested as distant metastasis. The emerging role of adiposity in both initiation and progression of metastasis is described. Defining the role of HOX genes in the metastatic process has identified candidates for targeted cancer therapies that may combat the metastatic process. We will discuss potential therapeutic opportunities, particularly in pathways influenced by HOX proteins.

Utility of NKX3.1 immunohistochemistry in the differential diagnosis of seminal vesicles versus prostatic tissue in needle biopsy

NKX3.1 is considered a reliable immunohistochemical marker of prostatic origin with high specificity and sensitivity. However, NKX3.1 positivity has been described in other neoplastic and non-neoplastic tissues, such as mesenchymal chondrosarcoma, sex-cord stromal tumors, rete testis adenocarcinoma, lobular and ductal carcinoma of the breast, salivary glands, peribronchial submucosal glands, and Sertoli cells. We analyzed expression of two antibodies (mono and polyclonal) of NKX3.1 in a total of 63 non-neoplastic seminal vesicles. We used 52 resection materials (12 seminal vesicles without prostatic adenocarcinoma, 26 seminal vesicles with prostatic adenocarcinoma infiltration, and 14 cases of seminal vesicles infiltrated by urothelial carcinoma) and 11 prostatic core needle biopsies with incidentally sampled fragment of seminal vesicles. In all cases, tissues from seminal vesicles were completely negative for NKX3.1, despite using polyclonal and monoclonal NKX3.1 antibodies, and regardless of the detection system utilized (diaminobenzidine (DAB) versus alkaline phosphatase (AF)). However, prostatic adenocarcinoma was negative in several cases (n = 6), when AF detection system was used. Reaction with DAB was strong and robust in all cases. Based on our data, we can recommend NKX3.1 as a negative immunohistochemical marker of seminal vesicles.

NKX3.1 Identifies Prostatic Origin of Dural Metastasis in the Setting of Negative Prostate-Specific Antigen Stain

No clear guidelines exist for the appropriate diagnostic workup of an intracranial mass suspected to be a metastasis from unknown primary origin. Dural metastasis from prostatic origin is very rare. Patients with a known history of metastatic prostate cancer who present with a newly discovered lesion on brain imaging require neurosurgical biopsy to confirm diagnosis prior to initiating treatment. Intracranial metastasis from prostate cancer is rare, and dural metastasis is rarer than intraparenchymal metastasis. Current consensus guidelines support immunohistochemical staining with classic markers such as prostate-specific antigen (PSA) to identify prostatic origin. However, PSA detection of prostate metastases declines with higher Gleason scores and in patients undergoing androgen deprivation therapy. NKX3.1 is another stain that is highly sensitive and specific for prostate. Our patient was a 54-year-old man with a history of metastatic prostate cancer who presented with new-onset seizures. Brain imaging revealed a dural-based lesion with surrounding vasogenic edema and midline shift. The patient underwent resection of the lesion, which was stained with multiple cancer markers. Prostate-specific antigen was negative, but NKX3.1 was positive indicating a prostatic origin for the mass. He underwent a craniectomy to remove the lesion and was given steroids. However, he succumbed to his illness several months later. Here, we document the first report to our knowledge of a patient with prostate metastasis to the dura that is PSA negative, but NKX3.1 positive.

Differential expression of NKX 3.1 and HOXB 13 in bone metastases originating from prostatic carcinoma among the Egyptian males

BACKGROUND

The skeleton represents one of the most common sites to be affected by metastatic tumors. About 65 % of all bone metastases come from the breast cancer in females, and from the prostatic carcinoma in males. A probable diagnostic pitfall may be encountered during the process of decalcification of the bone metastases specimens. This study aimed to evaluate the diagnostic utility of NKX3.1 and HOXB13 and compare them with the traditionally used PSA for the detection of prostatic origin of bone metastases.

MATERIAL AND METHODS

We analyzed 41 tissue specimens of bone metastases originating from prostatic carcinoma. Immunohistochemical staining of NKX3.1, HOXB13 and PSA was done with evaluation of their differential expression.

RESULTS

NKX3.1, HOXB 13 and PSA were expressed in (41/41), (39/41) and (25/41) respectively of the analyzed cases. On comparing NKX3.1 and HOXB13 positive staining, there was a statistically significant difference (P = 0.000). In addition, the frequency of positive NKX3.1 expression in decalcified bone biopsies of metastatic prostatic adenocarcinoma is statistically higher than that of PSA immunostaining (P = 0.000). We found a statistically significant difference between HOXB13 and PSA positive immunostaining (P = 0.01).

CONCLUSION

This study demonstrates that NKX3.1 and HOXB13 are more sensitive markers than PSA for the detection of prostate carcinoma metastatic to the bone following the decalcification process. We recommend use of NKX3.1 and HOXB13, rather than PSA, in the diagnosis of bone metastases originating from prostate cancer.

An Algorithmic Immunohistochemical Approach to Define Tumor Type and Assign Site of Origin

Immunohistochemistry represents an indispensable complement to an epidemiology and morphology-driven approach to tumor diagnosis and site of origin assignment. This review reflects the state of my current practice, based on 15-years' experience in Pathology and a deep-dive into the literature, always striving to be better equipped to answer the age old questions, "What is it, and where is it from?" The tables and figures in this manuscript are the ones I "pull up on the computer" when I am teaching at the microscope and turn to myself when I am (frequently) stuck. This field is so exciting because I firmly believe that, through the application of next-generation immunohistochemistry, we can provide better answers than ever before. Specific topics covered in this review include (1) broad tumor classification and associated screening markers; (2) the role of cancer epidemiology in determining pretest probability; (3) broad-spectrum epithelial markers; (4) noncanonical expression of broad tumor class screening markers; (5) a morphologic pattern-based approach to poorly to undifferentiated malignant neoplasms; (6) a morphologic and immunohistochemical approach to define 4 main carcinoma types; (7) CK7/CK20 coordinate expression; (8) added value of semiquantitative immunohistochemical stain assessment; algorithmic immunohistochemical approaches to (9) "garden variety" adenocarcinomas presenting in the liver, (10) large polygonal cell adenocarcinomas, (11) the distinction of primary surface ovarian epithelial tumors with mucinous features from metastasis, (12) tumors presenting at alternative anatomic sites, (13) squamous cell carcinoma versus urothelial carcinoma, and neuroendocrine neoplasms, including (14) the distinction of pheochromocytoma/paraganglioma from well-differentiated neuroendocrine tumor, site of origin assignment in (15) well-differentiated neuroendocrine tumor and (16) poorly differentiated neuroendocrine carcinoma, and (17) the distinction of well-differentiated neuroendocrine tumor G3 from poorly differentiated neuroendocrine carcinoma; it concludes with (18) a discussion of diagnostic considerations in the broad-spectrum keratin/CD45/S-100-"triple-negative" neoplasm.

Breast Metastasis From Castrate-Resistant Prostatic Adenocarcinoma Mimicking as a Second Primary: A Case Report

The occurrence of breast metastasis from prostate carcinoma and primary breast carcinoma in men may cause a diagnostic dilemma. This report aims to present a patient diagnosed with metastatic castrate-resistant prostatic adenocarcinoma who developed breast metastasis mimicking as a second primary. A 57-year-old male patient presented with a breast mass while undergoing hormonal therapy for prostatic adenocarcinoma. The initial histopathologic diagnosis of the breast specimen was an infiltrating ductal breast carcinoma. The breast mass enlarged after four cycles of docetaxel. Immunostaining with prostate-specific antigen (PSA) and prostate-specific acid phosphatase (PSAP) was done on the breast specimen revealing a negative PSA and a moderately staining PSAP. These stains confirmed the diagnosis of a breast metastasis from prostatic adenocarcinoma. The differentiation between primary breast carcinoma and breast metastasis from prostate carcinoma is crucial. Hence, immunohistochemistry staining should be utilized for diagnosis and appropriate management.

Utility of NKX3.1 Immunostaining in the Detection of Metastatic Prostatic Carcinoma on Fine-Needle Aspiration Smears

OBJECTIVES

NK3 homeobox 1 (NKX3.1) has been increasingly used to diagnose metastatic prostatic carcinoma in histologic samples. However, its utility and reliability in cytologic direct smears have not been studied.

METHODS

A total of 59 fine-needle aspiration (FNA) cases with a definitive diagnosis of metastatic carcinoma from the prostate were included. The cases were grouped based on different Gleason score in their corresponding primary tumors and morphologic variants. For each case, tumor cells were immunostained with NKX3.1, prostate-specific antigen (PSA), and prostatic acid phosphatase (PAP) on cell-transferred smears.

RESULTS

NKX3.1 was strongly and diffusely positive in all 40 metastatic prostatic adenocarcinomas, including those with ductal features, but negative for the 19 small cell carcinoma (SmCC) cases. NKX3.1 had a better detection rate than PSA (13/50, 26%) and PAP (0/47, 0%).

CONCLUSIONS

NKX3.1 immunostaining on FNA smears is highly reliable for detecting metastatic prostatic carcinomas of conventional and ductal types but not for SmCC.

Genetic variants in RUNX3, AMD1 and MSRA in the methionine metabolic pathway and survival in nonsmall cell lung cancer patients

Abnormal methionine dependence in cancer cells has led to methionine restriction as a potential therapeutic strategy. We hypothesized that genetic variants involved in methionine-metabolic genes are associated with survival in nonsmall cell lung cancer (NSCLC) patients. Therefore, we investigated associations of 16,378 common single-nucleotide polymorphisms (SNPs) in 97 methionine-metabolic pathway genes with overall survival (OS) in NSCLC patients using genotyping data from two published genome-wide association study (GWAS) datasets. In the single-locus analysis, 1,005 SNPs were significantly associated with NSCLC OS (p < 0.05 and false-positive report probability < 0.2) in the discovery dataset. Three SNPs (RUNX3 rs7553295 G > T, AMD1 rs1279590 G > A and MSRA rs73534533 C > A) were replicated in the validation dataset, and their meta-analysis showed an adjusted hazards ratio [HR] of 0.82 [95% confidence interval (CI) =0.75-0.89] and pmeta  = 2.86 × 10-6 , 0.81 (0.73-0.91) and pmeta  = 4.63 × 10-4 , and 0.77 (0.68-0.89) and pmeta  = 2.07 × 10-4 , respectively). A genetic score of protective genotypes of these three SNPs revealed an increased OS in a dose-response manner (ptrend  < 0.0001). Further expression quantitative trait loci (eQTL) analysis showed significant associations between these genotypes and mRNA expression levels. Moreover, differential expression analysis further supported a tumor-suppressive effect of MSRA, with lower mRNA levels in both lung squamous carcinoma and adenocarcinoma (p < 0.0001 and < 0.0001, respectively) than in adjacent normal tissues. Additionally, low mutation rates of these three genes indicated the critical roles of these functional SNPs in cancer progression. Taken together, these genetic variants of methionine-metabolic pathway genes may be promising predictors of survival in NSCLC patients.

Where is the limit of prostate cancer biomarker research? Systematic investigation of potential prognostic and diagnostic biomarkers

BACKGROUND

The identification of appropriate biomarkers is essential to support important clinical decisions in patients with prostate cancer. The aim of our study was a systematic bioinformatical analysis of the mRNA expression of all genes available for the prostate adenocarcinoma cohort of The Cancer Genome Atlas (TCGA), regarding their potential prognostic and diagnostic role.

METHODS

The study cohort comprises 499 patients (TCGA prostate cancer cohort). mRNA expression data were available for approx. 20,000 genes. The bioinformatical statistical pipeline addressed gene expression differences in tumor vs. benign prostate tissue (including gene set enrichment analysis, GSEA) in samples from tumors with different aggressivenesses (Gleason score), as well as prognostic values in multistep survival analyses.

RESULTS

Among all genes analyzed, 1754 were significantly downregulated and 1553 genes were significantly upregulated in tumor tissue. In GSEA, 16 of 30 top enriched biological processes were alterations of epigenetic regulation at different levels. Significant correlation with Gleason Score was evident for 8724 genes (range of Pearson r-values 0.09-0.43; all p < 0.05). In univariate Cox regression analyses, mRNA expression of 3571 genes showed statistically significant association with biochemical recurrence-free survival with a range of hazard ratios 0.3-3.8 (p-value 7.4e- 07 to 0.05). Among these, 571 genes were independently associated with biochemical recurrence in multivariate analysis. Access to the full database including results is provided as supplement.

CONCLUSIONS

In our systematic analysis we found a big number of genes of potential diagnostic and prognostic value, many of which have not been studied in prostate cancer to date. Due to the comprehensive nature of this analysis and free access to the results, this study represents a reference database for prostate cancer researchers which can be used as a powerful tool for validation purposes and planning of new studies.

Immunohistochemical Pitfalls in Genitourinary Pathology: 2018 Update

Immunohistochemistry may be a very useful adjunct to morphologic diagnosis in many areas of surgical pathology, including genitourinary pathology. In this review, we address common diagnostic dilemmas where immunophenotypic analysis may be utilized and we highlight pitfalls specific to each scenario. For prostate, we review the diagnosis of limited prostatic adenocarcinoma and the distinction of high-grade prostatic adenocarcinoma from urothelial carcinoma. We also cover markers of urothelial lineage in the diagnosis of metastatic carcinoma of unknown primary site. In the kidney, distinction of poorly differentiated renal cell carcinoma from urothelial carcinoma and epithelioid angiomyolipoma, adjuncts to the recognition of hereditary renal neoplasia, and the diagnosis of metastatic renal cell carcinoma are discussed. Finally, for testis we address distinction of germ cell tumors from sex cord-stromal tumors, as well as the diagnosis of metastatic germ cell tumors.

Markers of clinical utility in the differential diagnosis and prognosis of prostate cancer

Molecular diagnostics is a rapidly evolving area of surgical pathology, that is gradually beginning to transform our diagnostical procedures for a variety of tumors. Next to molecular prognostication that has begun to complement our histological diagnosis in breast cancer, additional testing to detect targets and to predict therapy response has become common practice in breast and lung cancer. Prostate cancer is a bit slower in this respect, as it is still largely diagnosed and classified on morphological grounds. Our diagnostic immunohistochemical armamentarium of basal cell markers and positive markers of malignancy now allows to clarify the majority of lesions, if applied to the appropriate morphological context (and step sections). Prognostic immunohistochemistry remains a problematic and erratic yet tempting research field that provides information on tumor relevance of proteins, but little hard data to integrate into our diagnostic workflow. Main reasons are various issues of standardization that hamper the reproducibility of cut-off values to delineate risk categories. Molecular testing of DNA-methylation or transcript profiling may be much better standardized and this review discusses a couple of commercially available tests: The ConfirmDX test measures DNA-methylation to estimate the likelihood of cancer detection on a repeat biopsy and may help to reduce unnecessary biopsies. The tests Prolaris, OncotypeDX Prostate, and Decipher all are transcript tests that have shown to provide prognostic data independent of clinico-pathological parameters and that may aid in therapy planning. However, further validation and more comparative studies will be needed to clarify the many open questions concerning sampling bias and tumor heterogeneity.