Keratin 17 is a sensitive and specific biomarker of urothelial neoplasia

Over-expression of KRT17 and MDK genes at mRNA levels in urine-exfoliated cells is associated with early non-invasive diagnosis of non-muscle-invasive bladder cancer

INTRODUCTION

Current diagnostic approaches for bladder cancer (BLCA) are often invasive or lack the required sensitivity and specificity. This underscores the need for an early non-invasive diagnostic test for BLCA. This work aimed to explore the potential of molecular markers in urine-exfoliated cells for the diagnosis of non-muscle-invasive bladder cancer (NMIBC).

MATERIALS AND METHODS

Urine specimens (n = 140) were collected from NMIBC patients (n = 68) and control subjects (31 healthy volunteers and 41 non-cancer patients with common urological diseases [CUD]. Total RNA was extracted from the cells isolated from urine specimens. mRNA expression of selected genes: CDC20, KRT15, FOXM1, CXCR2, UPK1B, MDK, KRT20, and KRT17 was determined using RT-qPCR. The receiver operating characteristic (ROC) curve was then plotted to obtain the area under the curve (AUC), specificity, and sensitivity of the urinary mRNA markers.

RESULTS

The expression of CDC20, MDK, UPK1B, FOXM1, KRT17, and KRT20 was up-regulated in samples obtained from low- and high-grade pathological grades of NMIBC compared to that measured in healthy subjects. Notably, MDK and KRT17 mRNA levels in the low- and high-grade cases were substantially higher than in normal and CUD groups. The AUC of the KRT17 and MDK combination in diagnosing NMIBC was 0.92, surpassing that of single genes. The sensitivity and specificity of the KRT17 and MDK combination were 74% and 94%, respectively. In diagnosing low-grade from healthy and CUD groups, analysis of the KRT17 and MDK combination yielded AUCs of 0.94 and 0.95, respectively, with sensitivities of 85% and 97%, and specificities of 93% and 85%.

CONCLUSION

The findings of this study revealed that KRT17 and MDK together are potential urine-based biomarkers for early diagnosis of NMIBC.

Advances in Liquid Biopsy for Diagnosis of Bladder Cancer

Bladder cancer (BCa) is the most common malignancy of the urinary system. It has a high recurrence rate and requires longterm follow-up. Significant advances in BCa research have been made in recent years; however, the initial diagnosis and follow-up of BCa relies on cystoscopy, which is an invasive and expensive procedure. Over the past decade, liquid biopsies (e.g., blood and urine) have proven to be highly efficient methods for the discovery of BCa biomarkers. This noninvasive sampling method is used to analyze unique tumor components released into body fluids and enables serial sampling and longitudinal monitoring of tumor progression. Several liquid biopsy biomarkers have been studied extensively and have shown promising results in the clinical applications of BCa, including early detection, microscopic residual disease detection, recurrence prediction, and treatment response. Therefore, this review aims to provide an update on various new liquid biopsy markers and the advantages and current limitations of liquid biopsy in the diagnosis of BCa.

Principles of Analytic Validation of Immunohistochemical Assays: Guideline Update

CONTEXT.—

In 2014, the College of American Pathologists developed an evidence-based guideline to address analytic validation of immunohistochemical assays. Fourteen recommendations were offered. Per the National Academy of Medicine standards for developing trustworthy guidelines, guidelines should be updated when new evidence suggests modifications.

OBJECTIVE.—

To assess evidence published since the release of the original guideline and develop updated evidence-based recommendations.

DESIGN.—

The College of American Pathologists convened an expert panel to perform a systematic review of the literature and update the original guideline recommendations using the Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS.—

Two strong recommendations, 1 conditional recommendation, and 12 good practice statements are offered in this updated guideline. They address analytic validation or verification of predictive and nonpredictive assays, and recommended revalidation procedures following changes in assay conditions.

CONCLUSIONS.—

While many of the original guideline statements remain similar, new recommendations address analytic validation of assays with distinct scoring systems, such as programmed death receptor-1 and analytic verification of US Food and Drug Administration approved/cleared assays; more specific guidance is offered for validating immunohistochemistry performed on cytology specimens.

Evaluation of URO17® to improve non-invasive detection of bladder cancer

BACKGROUND

The gold standard for detecting bladder cancer is cystoscopy with biopsy or transurethral resection confirming histologic diagnosis. URO17® employs a chromogenically labeled monoclonal antibody to keratin 17 (k17), an intermediate filament cytoskeleton molecule associated with bladder, pancreatic, and cervical cancers. Preliminary studies evaluating k17 demonstrated a high sensitivity and specificity for the detection of bladder cancer, supporting the need for further study.

OBJECTIVE

To evaluate the sensitivity and specificity of URO17.

METHODS

This is a cross-sectional study of participants undergoing urologic procedures between July 6, 2018 and July 17, 2019 at a single institution. Patients undergoing cystectomy, endoscopic bladder and/or upper tract procedure for probable urothelial carcinoma comprised cases; patients undergoing urologic procedures for other reasons comprised the control group (i.e. prostatectomy, nephrectomy, etc.). Voided urine samples were at the time of procedure; a minority of participants underwent multiple resections in the study period, thus, as many as three urine samples were taken from any given participant. Samples were distributed for blinded testing with URO17. Sensitivity and specificity were calculated.

RESULTS

In 152 participants and 167 samples, URO17 demonstrated an overall sensitivity of 90% and 92% and a specificity of 88% and 87%, respectively. In 76 participants and 91 samples from patients with suspected urothelial carcinoma, the sensitivity was 90% and 92%, and the specificity was 50% and 54%, respectively. No controls demonstrated a positive URO17 result, and URO17 superseded urine cytology detection of low-grade and high-grade Ta. False positive results were associated with inflamed tissue or urothelial atypia on histology; the large majority had a history of intravesical therapy.

CONCLUSION

Limitations include cross-sectional design and convenience sampling. URO17 may improve sensitivity of urine cytology in the detection of urothelial cancer, though further study is required to refine the application of this biomarker in clinical practice.

Acu-URO17 is a highly sensitive and specific bladder cancer biomarker

Objective

This study evaluates the efficacy of Acu-URO17, a highly sensitive and specific immunocytochemistry (ICC) test targeting Keratin 17, in comparison to urine cytology and UroVysion™ fluorescence in situ hybridization (FISH) for detecting bladder cancer cells in voided urine specimens.

Methods

Acupath conducted a large-scale comparison study using 2378 voided urine specimens. Acu-URO17, urine cytology and UroVysion™ FISH were performed on these specimens according to standardized protocols. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for Acu-URO17 in comparison to urine cytology and UroVysion™ FISH.

Results

In cases diagnosed with high-grade urothelial cancer via urine cytology, Acu-URO17 demonstrated a sensitivity of 96% and a specificity of 82%. When compared to UroVysion™ FISH results, Acu-URO17 exhibited a sensitivity of 97.1% and a specificity of 77.8%, surpassing the sensitivity of UroVysion™ FISH (57.1%). Notably, Acu-URO17 showed a high NPV of 99.9%, indicating its reliability in confirming negative urine cytology results and risk-stratifying atypical and suspicious cytology results.

Conclusion

The results of this large-scale prospective study support Acu-URO17 as a clinically relevant, non-invasive and cost-effective tool for detecting bladder cancer cells in voided urine specimens. Its high sensitivity, specificity and NPV make it a valuable adjunct to urine cytology and UroVysion™ FISH in the diagnosis and management of urothelial carcinoma (UC).

Enhancing upper tract urothelial carcinoma diagnosis: Utility of cytokeratin 17 and CK20/CD44/p53 immunohistochemical panel

Upper tract urothelial carcinoma (UTUC) presents diagnostic challenges due to small biopsy specimen size, poor orientation, and technical obstacles that can yield equivocal diagnoses. This uncertainty often mandates repeated biopsies to evaluate the necessity of nephroureterectomy. Prior studies have suggested cytokeratin 17 (CK17) immunostain as an adjunctive tool for diagnosing bladder urothelial neoplasia in both urine cytology and tissue biopsy specimens. We evaluated the utility of CK17 in differentiating UTUC from benign urothelium and its ability to stratify low-grade from high-grade neoplasia. Our study involved a cohort of previously diagnosed cytology (n = 29) and tissue specimens from biopsies and resections (n = 85). We evaluated CK17 staining percentage in cytology and tissue samples and localization patterns in biopsy/resection samples. Our findings showed a statistically significant distinction (p < 0.05) between UTUC and benign tissue specimens based on full thickness localization pattern (odds ratio 8.8 [95% CI 1.53-67.4]). The percentage of CK17 staining failed to significantly differentiate neoplastic from non-neoplastic cases in cytology or tissue samples. Additionally, based on prior research showing the efficacy of CK20/CD44/p53 triple panel in bladder urothelial neoplasia, we utilized tissue microarrays to evaluate if these markers could distinguish UTUC from benign urothelium. We found that CK20/CD44/p53, individually or in combination, could not distinguish urothelial neoplasia from non-neoplasia. Full thickness CK17 urothelial localization by immunohistochemistry was highly reproducible with excellent interobserver agreement and may play a supplementary role in distinguishing upper tract urothelial neoplasia from benign urothelium.

Cross-sectional and longitudinal analyses of urinary extracellular vesicle mRNA markers in urothelial bladder cancer patients

We designed this multi-center prospective study with the following objectives: (1) the cross-sectional validation of extracellular vesicles (EV) mRNA markers to detect urothelial bladder cancer (UBC) before transurethral resection of bladder cancer (TURBT), and (2) the longitudinal validation of EV mRNA markers to monitor non-muscle invasive bladder cancer (NMIBC) recurrence after TURBT. EV mRNA markers evaluated in this study were KRT17, GPRC5A, and SLC2A1 in addition to two additional markers from literatures, MDK and CXCR2, and measured by quantitative RT-PCR with normalization by a reference gene (ALDOB). Diagnostic performances of EV mRNA markers were compared to conventional markers. Regarding the first objective, we confirmed that EV mRNA biomarkers in urine were higher in UBC patients, particularly those with higher stage/grade tumors, than in those without UBC (n = 278 in total) and the diagnostic performance of EV mRNA MDK and KRT17 outperformed conventional biomarkers with AUC 0.760 and 0.730, respectively. Concerning the second objective, we prospectively analyzed the time courses of EV mRNA markers while NMIBC patients (n = 189) (median follow-up 19 months). The expression of EV mRNA KRT17 was significantly high in patients with recurrence, while it gradually decreased over time in those without recurrence (p < 0.01).

Urinary markers for bladder cancer diagnosis: A review of current status and future challenges

Bladder cancer is a common urological cancer with a high recurrence rate that requires long-term follow-up, and early detection positively affects prognosis. To date, the initial diagnosis and follow-up for bladder cancer rely on cystoscopy, which is an invasive and expensive procedure. Therefore, urinary markers for the detection of bladder cancer have attracted research attention for decades to reduce unnecessary cystoscopies. Urine, which is in continuous contact with bladder cancer, is considered a suitable fluid for providing tumor information. Urinary cytology is the only widely used urinary marker in clinical practice; however, it has poor sensitivity for low-grade tumors; indicating the need for novel urinary markers. Considerable research has been conducted on this topic over the years, resulting in a complex landscape with a wide range of urinary markers, including protein-, exfoliated cell-, RNA-, DNA-, and extracellular vesicle-based markers. Although some of these markers have been approved by the U.S. Food and Drug Administration and are commercially available, their use in clinical practice is limited. To facilitate clinical application, potential urinary markers must withstand prospective clinical trials and be easy for patients and clinicians to understand and utilize in a clinical context. This review provides a comprehensive overview of currently available and recently reported promising urinary markers for bladder cancer. Additionally, the challenges and the prospects of these urinary markers for clinical implementation in bladder cancer treatment were discussed.

Current look at the most promising proteomic and glycomic biomarkers of bladder cancer

BACKGROUND

Bladder cancer (BC) belongs to the most frequent cancer types. The diagnostic process is still long and costly, with a high percentage of false-positive or -negative results. Due to the cost and lack of effectiveness, older methods need to be supplemented or replaced by a newer more reliable method. In this regard, proteins and glycoproteins pose high potential.

METHODS

We performed an online search in PubMed/Medline, Scopus, and Web of Science databases to find relevant studies published in English up until May 2023. If applicable, we set the AUC threshold to 0.90 and sensitivity/specificity (SN/SP) to 90%.

FINDINGS

Protein and glycoprotein biomarkers are a demonstrably viable option in BC diagnostics. Cholinesterase shows promise in progression-free survival. BLCA-4, ORM-1 along with HTRA1 in the detection of BC. Matrix metallopeptidase 9 exhibits potential for stratification of muscle-invasive subtypes with high negative predictive value for aggressive phenotypes. Distinguishing non-muscle invasive subtypes benefits from Keratin 17. Neu5Gc-modified UMOD glycoproteins pose potential in BC diagnosis, while fibronectin, laminin-5, collagen type IV, and lamprey immunity protein in early detection of BC.

Emerging Prognostic and Predictive Significance of Stress Keratin 17 in HPV-Associated and Non HPV-Associated Human Cancers: A Scoping Review

A growing body of literature suggests that the expression of cytokeratin 17 (K17) correlates with inferior clinical outcomes across various cancer types. In this scoping review, we aimed to review and map the available clinical evidence of the prognostic and predictive value of K17 in human cancers. PubMed, Web of Science, Embase (via Scopus), Cochrane Central Register of Controlled Trials, and Google Scholar were searched for studies of K17 expression in human cancers. Eligible studies were peer-reviewed, published in English, presented original data, and directly evaluated the association between K17 and clinical outcomes in human cancers. Of the 1705 studies identified in our search, 58 studies met criteria for inclusion. Studies assessed the prognostic significance (n = 54), predictive significance (n = 2), or both the prognostic and predictive significance (n = 2). Altogether, 11 studies (19.0%) investigated the clinical relevance of K17 in cancers with a known etiologic association to HPV; of those, 8 (13.8%) were focused on head and neck squamous cell carcinoma (HNSCC), and 3 (5.1%) were focused on cervical squamous cell carcinoma (SCC). To date, HNSCC, as well as triple-negative breast cancer (TNBC) and pancreatic cancer, were the most frequently studied cancer types. K17 had prognostic significance in 16/17 investigated cancer types and 43/56 studies. Our analysis suggests that K17 is a negative prognostic factor in the majority of studied cancer types, including HPV-associated types such as HNSCC and cervical cancer (13/17), and a positive prognostic factor in 2/17 studied cancer types (urothelial carcinoma of the upper urinary tract and breast cancer). In three out of four predictive studies, K17 was a negative predictive factor for chemotherapy and immune checkpoint blockade therapy response.

Molecular Markers for Bladder Cancer Screening: An Insight into Bladder Cancer and FDA-Approved Biomarkers

Bladder cancer is one of the most financially burdensome cancers globally, from its diagnostic to its terminal stages. The impact it imposes on patients and the medical community is substantial, exacerbated by the absence of disease-specific characteristics and limited disease-free spans. Frequent recurrences, impacting nearly half of the diagnosed population, require frequent and invasive monitoring. Given the advancing comprehension of its etiology and attributes, bladder cancer is an appealing candidate for screening strategies. Cystoscopy is the current gold standard for bladder cancer detection, but it is invasive and has the potential for undesired complications and elevated costs. Although urine cytology is a supplementary tool in select instances, its efficacy is limited due to its restricted sensitivity, mainly when targeting low-grade tumors. Although most of these assays exhibit higher sensitivity than urine cytology, clinical guidelines do not currently incorporate them. Consequently, it is necessary to explore novel screening assays to identify distinctive alterations exclusive to bladder cancer. Thus, integrating potential molecular assays requires further investigation through more extensive validation studies. Within this article, we offer a comprehensive overview of the critical features of bladder cancer while conducting a thorough analysis of the FDA-approved assays designed to diagnose and monitor its recurrences.

Perception of urinary biomarker tests among patients referred with suspected urological malignancy

Objective

To determine the acceptability of a non-invasive urinary biomarker test in place of conventional flexible cystoscopy for the diagnosis of bladder cancer in patients referred to a Rapid Access Haematuria Clinic (RAHC) with suspected urological malignancy.

Patients and methods

Patients attending a RAHC were recruited to a prospective observational study evaluating a novel urinary biomarker (URO17™) for the detection of bladder cancer and invited to complete a two-part structured questionnaire. Questions related to demographics, attitudes towards conventional cystoscopy and the minimal acceptable sensitivity (MAS) at which a urinary biomarker would be considered an alternative to flexible cystoscopy both before and after undergoing the procedure.

Results

A total of 250 patients completed the survey; the majority of whom were referred with visible haematuria (75.2%). One hundred seventy-one (68.4%) would be willing to accept a urinary biomarker in place of cystoscopy, with 59 (23.6%) expressing preference for the biomarker with a MAS as low as 85%. Conversely, 74 patients (29.6%) would not be willing to accept a urinary biomarker, regardless of its sensitivity. A significant number of patients reported a change in MAS after undergoing cystoscopy, with 80 (32.0%) and 16 (6.4%) increasing and decreasing the required value respectively (P = 0.001). The greatest increase was seen in the proportion of patients unwilling to accept a urinary biomarker regardless of its sensitivity, rising from 29.6% to 38.4%.

Conclusions

Although many patients attending a RAHC would be willing to accept a urinary biomarker test in place of conventional flexible cystoscopy for the detection of bladder cancer, effective patient, public and clinician engagement will be necessary at all stages of implementation if it is to become an established component of the diagnostic pathway.

Advances in Diagnosis and Therapy for Bladder Cancer

Bladder cancer (BCa) is one of the most common and expensive urinary system malignancies for its high recurrence and progression rate. In recent years, immense amounts of studies have been carried out to bring a more comprehensive cognition and numerous promising clinic approaches for BCa therapy. The development of innovative enhanced cystoscopy techniques (optical techniques, imaging systems) and tumor biomarkers-based non-invasive urine screening (DNA methylation-based urine test) would dramatically improve the accuracy of tumor detection, reducing the risk of recurrence and progression of BCa. Moreover, intravesical instillation and systemic therapeutic strategies (cocktail therapy, immunotherapy, vaccine therapy, targeted therapy) also provide plentiful measures to break the predicament of BCa. Several exploratory clinical studies, including novel surgical approaches, pharmaceutical compositions, and bladder preservation techniques, emerged continually, which are supposed to be promising candidates for BCa clinical treatment. Here, recent advances and prospects of diagnosis, intravesical or systemic treatment, and novel drug delivery systems for BCa therapy are reviewed in this paper.

Proteomics for Early Detection of Non-Muscle-Invasive Bladder Cancer: Clinically Useful Urine Protein Biomarkers

Bladder cancer is the fourth most common cancer in men, and most cases are non-muscle-invasive. A high recurrence rate is a critical problem in non-muscle-invasive bladder cancer. The availability of few urine tests hinders the effective detection of superficial and small bladder tumors. Cystoscopy is the gold standard for diagnosis; however, it is associated with urinary tract infections, hematuria, and pain. Early detection is imperative, as intervention influences recurrence. Therefore, urinary biomarkers need to be developed to detect these bladder cancers. Recently, several protein candidates in the urine have been identified as biomarkers. In the present narrative review, the current status of the development of urinary protein biomarkers, including FDA-approved biomarkers, is summarized. Additionally, contemporary proteomic technologies, such as antibody-based methods, mass-spectrometry-based methods, and machine-learning-based diagnosis, are reported. Furthermore, new strategies for the rapid and correct profiling of potential biomarkers of bladder cancer in urine are introduced, along with their limitations. The advantages of urinary protein biomarkers and the development of several related technologies are highlighted in this review. Moreover, an in-depth understanding of the scientific background and available protocols in research and clinical applications of the surveillance of non-muscle bladder cancer is provided.

Keratin 17 Promotes T Cell Response in Allergic Contact Dermatitis by Upregulating C-C Motif Chemokine Ligand 20

Allergic contact dermatitis (ACD) is a delayed-type hypersensitivity response to skin contact allergens in which keratinocytes are critical in the initiation of early responses. Keratin 17 (K17) is a cytoskeletal protein inducible under stressful conditions and regulates multiple cellular processes, especially in skin inflammatory diseases; however, knowledge regarding its contribution to ACD pathogenesis remains ill defined. In the present study, we clarified the proinflammatory role of K17 in an oxazolone (OXA)-induced contact hypersensitivity (CHS) murine model and identified the underlying molecular mechanisms. Our results showed that K17 was highly expressed in the lesional skin of ACD patients and OXA-induced CHS mice. Mice lacking K17 exhibited alleviated OXA-induced skin inflammation, including milder ear swelling, a reduced frequency of T cell infiltration, and decreased inflammatory cytokine levels. In vitro, K17 stimulated and activated human keratinocytes to produce plenty of proinflammatory mediators, especially the chemokine CCL20, and promoted keratinocyte-mediated T cell trafficking. The neutralization of CCL20 with a CCL20-neutralizing monoclonal antibody significantly alleviated OXA-induced skin inflammation in vivo. Moreover, K17 could translocate into the nucleus of activated keratinocytes through a process dependent on the nuclear-localization signal (NLS) and nuclear-export signal (NES) sequences, thus facilitating the activation and nuclear translocation of signal transducer and activator of transcription 3 (STAT3), further promoting the production of CCL20 and T cell trafficking to the lesional skin. Taken together, these results highlight the novel roles of K17 in driving allergen-induced skin inflammation and suggest targeting K17 as a potential strategy for ACD.

The Role of Keratin17 in Human Tumours

Keratins are a group of proteins that can constitute intermediate fibers. It is a component of the cytoskeleton and plays an important role in cell protection and structural support. Keratin 17, a Type I keratin, is a multifunctional protein that regulates a variety of biological processes, including cell growth, proliferation, migration, apoptosis and signal transduction. Abnormal expression of KRT17 is associated with a variety of diseases, such as skin diseases. In recent years, studies have shown that KRT17 is abnormally expressed in a variety of malignant tumours, such as lung cancer, cervical cancer, oral squamous cell carcinoma and sarcoma. These abnormal expressions are related to the occurrence, development and prognosis of malignant tumors. In this review, we summarized the expression patterns of KRT17 in a variety of malignant tumours, the role of KRT17 in the development and prognosis of different malignant tumors and its molecular mechanisms. We also discuss the potential clinical application of KRT17 as a valuable therapeutic target.

Keratin 17 upregulation promotes cell metastasis and angiogenesis in colon adenocarcinoma

Colon adenocarcinoma (COAD), having high malignancy and poor prognosis, is the main pathological type of colon cancer. Previous studies show that Keratin 17 (KRT17) plays an important role in the development of many malignant tumors. However, its role and the molecular mechanism underlying COAD remain unclear. Using TCGA and ONCOMINE databases, as well as immunohistochemistry, we found that the expression of KRT17 was higher in COAD tissues as compared to that in the adjacent normal tissues. Cell- and animal-based experiments showed that overexpression of KRT17 promoted the invasion and metastasis of colon cancer cells while knocking down KRT17 reversed these processes both in vitro and in vivo. In addition, we also showed that KRT17 promoted the formation of new blood vessels. Mechanistically, KRT17 could regulate the WNT/β-catenin signaling pathway, and APC may be involved in this process by interacting with KRT17. In summary, these findings suggested that high expression of KRT17 could promote cell metastasis and angiogenesis of colon cancer cells by regulating the WNT/β-catenin signaling pathway. Thus, KRT17 could be a potential therapeutic target for COAD treatment.

Keratin 17 testing in pancreatic cancer needle aspiration biopsies predicts survival

BACKGROUND

Although pancreatic ductal adenocarcinoma (PDAC) has one of the lowest 5-year survival rates of all cancers, differences in survival exist between patients with clinically identical characteristics. The authors previously demonstrated that keratin 17 (K17) expression in PDAC, measured by RNA sequencing or immunohistochemistry (IHC), is an independent negative prognostic biomarker. Only 20% of cases are candidates for surgical resection, but most patients are diagnosed by needle aspiration biopsy (NAB). The aims of this study were to determine whether there was a correlation in K17 scores detected in matched NABs and surgical resection tissue sections and whether K17 IHC in NAB cell block specimens could be used as a negative prognostic biomarker in PDAC.

METHODS

K17 IHC was performed for a cohort of 70 patients who had matched NAB cell block and surgical resection samples to analyze the correlation of K17 expression levels. K17 IHC was also performed in cell blocks from discovery and validation cohorts. Kaplan-Meier and Cox proportional hazards regression models were analyzed to determine survival differences in cases with different levels of K17 IHC expression.

RESULTS

K17 IHC expression correlated in matched NABs and resection tissues. NAB samples were classified as high for K17 when ≥80% of tumor cells showed strong (2+) staining. High-K17 cases, including stage-matched cases, had shorter survival.

CONCLUSIONS

K17 has been identified as a robust and independent prognostic biomarker that stratifies clinical outcomes for cases that are diagnosed by NAB. Testing for K17 also has the potential to inform clinical decisions for optimization of chemotherapeutic interventions.

Keratin 17 Is a Novel Cytologic Biomarker for Urothelial Carcinoma Diagnosis

OBJECTIVES

The microscopic features of urine cytology specimens are subjective and may not reliably distinguish between benign urothelial cells and low-grade urothelial carcinoma (UC). Prior studies demonstrated that keratin 17 (K17) detection in biopsies is highly sensitive for UC. The current study aimed to define K17 diagnostic test performance for initial screening and detect recurrent UC in urine specimens.

METHODS

K17 was detected by immunocytochemistry (ICC) in consecutively collected urine specimens (2018-2019). A qualitative score for the K17 test was determined in 81 samples (discovery cohort) and validated in 98 samples (validation cohort). K17 sensitivity and specificity were analyzed in both cohorts across all grades of UC.

RESULTS

Based on the discovery cohort, the presence of 5 or more K17 immunoreactive urothelial cells (area under the curve = 0.90; P < .001) was the optimal threshold to define a K17-positive test. The sensitivity of the K17 ICC test for biopsy-confirmed UC was 35 of 36 (97%) and 18 of 21 (86%) in the discovery and validation cohorts, respectively. K17 was positive in 16 of 19 (84%) specimens with biopsy-confirmed low-grade UC and in 34 of 34 (100%) of specimens with high-grade UC.

CONCLUSIONS

K17 ICC is a highly sensitive diagnostic test for initial screening and detection of recurrence across all grades of UC.

Biomarkers in Bladder Cancer Surveillance

Aim: This is a narrative review with an aim to summarise and describe urinary biomarkers in the surveillance of non-muscle-invasive bladder cancer (NMIBC). It provides a summary of FDA-approved protein biomarkers along with emerging ones which utilise genetic, epigenetic and exosomal markers. We discuss the current limitations of the available assays. Background: Current guidelines advice a combination of cystoscopy, imaging,and urine cytology in diagnosis and surveillance. Although cytology has a high specificity, it is limited by low sensitivity particularly in low grade tumours. There are six FDA-approved urinary assays for diagnosis and surveillance of bladder cancer. They have shown to improve sensitivity and specificity to be used alongside cytology and cystoscopy but have a lower specificity in comparison to cytology and false positives often occur in benign conditions. Recent developments in laboratory techniques has allowed for use of markers which are RNA-, DNA-based as well as extracellular vesicles in the past decade. Methods: Using the PubMed/Medline search engines as well as Google Scholar, we performed an online search using the terms "bladder cancer," "non-muscle invasive bladder cancer," and "urine biomarkers" with filter for articles in English published up to May 2021. Systematic reviews and original data of clinical trials or observational studies which contributed to the development of the biomarkers were collated. Results: Biomarkers identified were divided into FDA-approved molecular biomarkers, protein biomarkers and gene-related biomarker with a table summarising the findings of each marker with the most relevant studies. The studies conducted were mainly retrospective. Due to the early stages of development, only a few prospective studies have been done for more recently developed biomarkers and limited meta-analyses are available.Therefore a detailed evaluation of these markers are still required to decide on their clinical use. Conclusion: Advancements of analytical methods in BC has driven the research towards non-invasive liquid-based biomarkers in adjunct to urine cytology. Further large prospective studies are required to determine its feasibility in a clinical setting as they are not effective when used in isolation as they have their limitation. With the ongoing pandemic, other than reduction in costs and increased accuracy, the need for biomarkers to cope with delay in cystoscopies in diagnosis and surveillance is crucial. Thus clinical trials with direct comparison is required to improve patient care.

Keratin 17 is Not Always a Marker of Proliferation of Keratinocytes in Skin Diseases

Purpose

Keratin 17 (K17) is an embryonic keratin and overexpression is seen in psoriasis, which is a hyperproliferation skin disease. Nonetheless, whether it is also highly expressed in other proliferative skin diseases remains unclear. The aim of this study is to explore the expression of K17 in cutaneous lichen planus (CLP), lichen simplex chronicus (LSC), and prurigo nodularis (PN).

Methods

A total of 20 skin samples from CLP lesions, 20 from LSC lesions, 20 from PN lesions, and 10 healthy adult skin tissues were obtained. Then, the expression of K17 was analyzed using immunohistochemistry on paraffin-embedded tissue sections. Furthermore, quantitative and semi-quantitative immunohistochemical scores of K17 were independently evaluated under a microscope by 2 dermatologists.

Results

Immunohistochemical analysis revealed that in normal skin, K17 was minimally expressed. Nevertheless, it was highly expressed in all epidermal layers in CLP lesions (P-value <0.01), and negatively expressed in LSC and PN lesions (all P-value >0.05). The average gray value of K17 in CLP was 151.153±13.985 (P-value <0.001), while the average values of K17 in LSC and PN were 178.720±12.001 and 181.316±8.920, respectively (all P-value >0.05).

Conclusion

K17 is potentially expressed in certain inflammatory skin diseases, including psoriasis and lichen planus. Besides, it is not always a marker of hyperproliferation of keratinocytes in skin diseases.

Impact of infections, preneoplasia and cancer on micronucleus formation in urothelial and cervical cells: A systematic review

Approximately 165,000 and 311,000 individuals die annually from urothelial (UC) and cervical (CC) cancer. The therapeutic success of these cancers depends strongly on their early detection and could be improved by use of additional diagnostic tools. We evaluated the current knowledge of the use of micronucleus (MN) assays (which detect structural and numerical chromosomal aberrations) with urine- (UDC) and cervix-derived (CDC) cells for the identification of humans with increased risks and for the diagnosis of UC and CC. Several findings indicate that MN rates in UDC are higher in individuals with inflammation and schistosomiasis that are associated with increased prevalence of UC; furthermore, higher MN rates were also found in CDC in women with HPV, Candidiasis and Trichomonas infections which increase the risks for CC. Only few studies were published on MN rates in UDS in patients with UC, two concern the detection of recurrent bladder tumors. Strong correlations were found in individuals with abnormal CC cells that are scored in Pap tests and histopathological abnormalities. In total, 16 studies were published which concerned these topics. MN rates increased in the order: inflammation < ASC-US/ASC-H < LSIL < HSIL < CC. It is evident that MNi numbers increase with the risk to develop CC and with the degree of malignant transformation. Overall, the evaluation of the literature indicates that MNi are useful additional biomarkers for the prognosis and detection of CC and possibly also for UC. In regard to the diagnosis/surveillance of UC, further investigations are needed to draw firm conclusions, but the currently available data are promising. In general, further standardization of the assays is needed (i.e. definition of optimal cell numbers and of suitable stains as well as elucidation of the usefulness of parameters reflecting cytotoxicity and mitotic activity) before MN trials can be implemented in routine screening.

The role of URO17™ biomarker to enhance diagnosis of urothelial cancer in new hematuria patients—First European Data

Introduction and objectives

Novel biomarker research is vital for the progression of safe and thorough diagnostic medicine. There is now a need to improve the diagnosis of bladder cancer via a noninvasive urine test while balancing the risks of harm from investigational procedures, such as cystoscopy and radiological tests, against the likelihood of malignancy. We evaluate the diagnostic accuracy and sensitivity of Uro17™ urinary biomarker for the detection of urothelial cancer in hematuria patients in a prospective blinded validation study. Uro17™ is an immunobiomarker which binds to the oncoprotein Keratin 17, which is involved in the replication cycle of malignant cells. This study compared cystoscopic and histological investigations against Uro17™ results in patients being investigated for symptoms of urothelial cancer.

Materials and methods

After receiving both local and national ethics/protocol approval, 71 patients were consented and recruited into the study. All patients were scheduled to undergo cystoscopic investigation, and following recruitment, a urine sample was collected. Urine samples were anonymized and processed as per standard cytology protocols and stained using Uro17™ immunobiomarker. The pathologists assessing the results were blinded to the patient and background history, and the results were compared to the biopsy histology.

Results

The full cohort of enrolled patients consisted of 71 participants included. There were 55 males and 16 females, with an average age of 70. Thirteen were current smokers, 42 ex‐smokers, and 16 nonsmokers. The malignancies detected included both muscle‐invasive (n = 6) and non‐muscle‐invasive tumors (n = 38), and tumors of all grades and carcinoma in situ. Uro17™ was shown to have an overall sensitivity of 100% and a specificity of 92.6%, with a positive predictive value of 0.957 and negative predictive value of 1. Uro17™ investigation was positive in every case of urothelial malignancy.

Conclusions

Our current data indicates Uro17™ is a highly sensitive noninvasive bladder cancer urine detection test that can improve the diagnosis of Bladder cancer. This can further improve diagnostic capabilities in primary care, reduce the number of referrals to Urology department, and reduce the number of unnecessary invasive procedures for new patients with a suspected urinary bladder cancer.

The Urothelium: Life in a Liquid Environment

The urothelium, which lines the renal pelvis, ureters, urinary bladder, and proximal urethra, forms a high-resistance but adaptable barrier that surveils its mechanochemical environment and communicates changes to underlying tissues including afferent nerve fibers and the smooth muscle. The goal of this review is to summarize new insights into urothelial biology and function that have occurred in the past decade. After familiarizing the reader with key aspects of urothelial histology, we describe new insights into urothelial development and regeneration. This is followed by an extended discussion of urothelial barrier function, including information about the roles of the glycocalyx, ion and water transport, tight junctions, and the cellular and tissue shape changes and other adaptations that accompany expansion and contraction of the lower urinary tract. We also explore evidence that the urothelium can alter the water and solute composition of urine during normal physiology and in response to overdistension. We complete the review by providing an overview of our current knowledge about the urothelial environment, discussing the sensor and transducer functions of the urothelium, exploring the role of circadian rhythms in urothelial gene expression, and describing novel research tools that are likely to further advance our understanding of urothelial biology.

Urinary biomarkers in bladder cancer: A review of the current landscape and future directions

AIM

This narrative review aims to describe established and emerging urinary biomarkers in the diagnosis and surveillance of non-muscle invasive bladder cancer. It provides a comprehensive account of classical, FDA-approved protein biomarkers and discusses their limitations. Further, we discuss the role that epigenetic, genetic, and exosomal markers can play to enhance sensitivity and specificity of the available tests.

BACKGROUND

The initial diagnosis and surveillance of bladder cancer involves a combination of cystoscopy, upper urinary tract imaging, and urine cytology. Despite high specificity, cytology is limited by low sensitivity. There are currently 6 urinary assays approved by the FDA to enhance diagnosis and surveillance of bladder cancer. While these have improved diagnosis and surveillance when combined with cytology, these tests are still not sufficiently sensitive and false positives often occur in benign conditions which result in inflammation of the urinary tract. Advancements in laboratory techniques have produced significant advancements in epigenetic and genetic markers, as well as extracellular vesicles, with DNA- and RNA-based markers dominating the research in this area in recent years.

METHODS

We identified relevant published data, using the PubMed/ Medline search engines as well as Google Scholar. We performed an online search using the terms "bladder cancer", "non-muscle invasive bladder cancer" in combination with "urine biomarkers" and limited articles in English published up to February 2020. This review consolidated on all available narrative and systematic reviews published in the 5 years in this field, while also reviewing the original data of each clinical trial or observational study which led to the development of the biomarkers.

CONCLUSION

The development of laboratory techniques and understanding urine-based biomarkers in BC has fuelled the use of noninvasive liquid-based biomarkers to complement urine cytology. Nonetheless, none are sufficiently effective when used in isolation, and cytology remains the gold standard in many practices. Future efforts will be focused on using these markers in combination as a predictive signature, and moving on to validating them for use in everyday clinical practice.

Deep learning-based image analysis methods for brightfield-acquired multiplex immunohistochemistry images

BACKGROUND

Multiplex immunohistochemistry (mIHC) permits the labeling of six or more distinct cell types within a single histologic tissue section. The classification of each cell type requires detection of the unique colored chromogens localized to cells expressing biomarkers of interest. The most comprehensive and reproducible method to evaluate such slides is to employ digital pathology and image analysis pipelines to whole-slide images (WSIs). Our suite of deep learning tools quantitatively evaluates the expression of six biomarkers in mIHC WSIs. These methods address the current lack of readily available methods to evaluate more than four biomarkers and circumvent the need for specialized instrumentation to spectrally separate different colors. The use case application for our methods is a study that investigates tumor immune interactions in pancreatic ductal adenocarcinoma (PDAC) with a customized mIHC panel.

METHODS

Six different colored chromogens were utilized to label T-cells (CD3, CD4, CD8), B-cells (CD20), macrophages (CD16), and tumor cells (K17) in formalin-fixed paraffin-embedded (FFPE) PDAC tissue sections. We leveraged pathologist annotations to develop complementary deep learning-based methods: (1) ColorAE is a deep autoencoder which segments stained objects based on color; (2) U-Net is a convolutional neural network (CNN) trained to segment cells based on color, texture and shape; and ensemble methods that employ both ColorAE and U-Net, collectively referred to as (3) ColorAE:U-Net. We assessed the performance of our methods using: structural similarity and DICE score to evaluate segmentation results of ColorAE against traditional color deconvolution; F1 score, sensitivity, positive predictive value, and DICE score to evaluate the predictions from ColorAE, U-Net, and ColorAE:U-Net ensemble methods against pathologist-generated ground truth. We then used prediction results for spatial analysis (nearest neighbor).

RESULTS

We observed that (1) the performance of ColorAE is comparable to traditional color deconvolution for single-stain IHC images (note: traditional color deconvolution cannot be used for mIHC); (2) ColorAE and U-Net are complementary methods that detect 6 different classes of cells with comparable performance; (3) combinations of ColorAE and U-Net into ensemble methods outperform using either ColorAE and U-Net alone; and (4) ColorAE:U-Net ensemble methods can be employed for detailed analysis of the tumor microenvironment (TME). We developed a suite of scalable deep learning methods to analyze 6 distinctly labeled cell populations in mIHC WSIs. We evaluated our methods and found that they reliably detected and classified cells in the PDAC tumor microenvironment. We also present a use case, wherein we apply the ColorAE:U-Net ensemble method across 3 mIHC WSIs and use the predictions to quantify all stained cell populations and perform nearest neighbor spatial analysis. Thus, we provide proof of concept that these methods can be employed to quantitatively describe the spatial distribution immune cells within the tumor microenvironment. These complementary deep learning methods are readily deployable for use in clinical research studies.

Keratin 17 Expression Predicts Poor Clinical Outcome in Patients With Advanced Esophageal Squamous Cell Carcinoma

The major roles of keratin 17 (K17) as a prognostic biomarker have been highlighted in a range of human malignancies. However, its relevance to esophageal squamous cell carcinoma (ESCC) remains unexplored. In this study, the relationship between K17 expression and clinicopathologic parameters and survival were determined by RNA sequencing (RNA-Seq) in 90 ESCCs and by immunohistochemistry (IHC) in 68 ESCCs. K17 expression was significantly higher in ESCC than in paired normal tissues at both the messenger RNA and protein levels. K17 messenger RNA and staining by IHC were significantly correlated with aggressive characteristics, including advanced clinical stage, invasion depth, and lymph node metastases; and were predictive of poor prognosis in advanced disease patients. Furthermore, K17 expression was detected by IHC in high-grade premalignant lesions of the esophageal mucosa, suggesting that K17 could also be a biomarker of dysplasia of the esophageal mucosa. Overall, this study established that K17 is a negative prognostic biomarker for the most common subtype of esophageal cancer.

ITGBL1 promotes cell migration and invasion through stimulating the TGF-β signalling pathway in hepatocellular carcinoma

Objectives

Integrin beta‐like 1 (ITGBL1) is involved in the migration and invasion of several cancers; however, its roles in the development and progression of hepatocellular carcinoma (HCC) remain largely unknown.

Materials and methods

Immunohistochemistry staining was used to investigate the expression pattern of ITGBL1 and its prognostic values in HCC patients. The transwell, wound‐healing assays, xenograft and orthotopic mouse models were employed to determine the effects of ITGBL1 on HCC cell migration and invasion in vitro and in vivo. The biological mechanisms involved in cell migration and invasion caused by ITGBL1 were determined with Western blotting and RT‐PCR methods.

Results

ITGBL1 expression was significantly increased in HCC tissues compared to adjacent normal tissues. Patients with higher ITGBL1 expression were associated with more reduced overall survival. ITGBL1 overexpression promoted migration and invasion in SMMC‐7721 and HepG2 cells in vitro and in vivo, whereas knockdown or knockout ITGBL1 in CSQT‐2 cells significantly reduced cell migration and invasion abilities. In SMMC‐7721 cells, ITGBL1 overexpression stimulated TGF‐β/Smads signalling pathway, along with the KRT17 and genes involved in the epithelial‐mesenchymal transition (EMT). In contrast, ITGBL1 knockout inhibited the TGF‐β/Smads signalling pathway in CSQT‐2 cells.

Conclusions

These findings suggested that ITGBL1 promoted migration and invasion in HCC cells by stimulating the TGF‐β/Smads signalling pathway. ITGBL1 could be a promising prognostic biomarker, as well as a potential therapeutic target in HCC.

An institutional experience evaluating hTERT immunostaining in 100 consecutive ThinPrep urine specimens

INTRODUCTION

Studies have shown that expression of human telomerase reverse transcriptase (hTERT) in mature urothelial cells indicates an increased risk of urothelial carcinoma. We evaluated the utility of immunocytochemistry with a commercially available anti-hTERT antibody (SCD-A7) in 100 consecutive urine cytology specimens using ThinPrep processing.

MATERIALS AND METHODS

ThinPrep slides prepared from 100 consecutive urine specimens were stained using anti-hTERT antibody (SCD-A7) after staining optimization had been successfully completed. Patient demographics, cytology diagnoses, histologic follow-up data, and anti-hTERT staining results were recorded.

RESULTS

The cytology diagnoses included 7 cases of high-grade urothelial carcinoma (HGUC), 2 cases suspicious for HGUC (SHGUC), 24 cases of atypical urothelial cells (AUCs), and 67 cases negative for HGUC (NHGUC). Of 92 samples, 68 (74%) were positive and 24 (26%) were negative for anti-hTERT staining. Although 31 of 32 specimens (97%) with a diagnosis of AUCs and greater showed positive staining, 37 of 60 NHGUC cases (62%) were also positive for anti-hTERT. Although the HGUC and suspicious for HGUC cases were more likely to show strong staining (6 of 9; 67%), 7 AUC (32%) and 8 NHGUC (22%) cases also demonstrated strong staining. Eight samples (8%) were unsatisfactory for interpretation. Anti-hTERT staining of nonurothelial cells was seen in 77 of 92 samples (84%).

CONCLUSIONS

Interpretation of anti-hTERT immunocytochemical staining of ThinPrep material is challenging owing to obscuring of nonurothelial cell staining and difficulty discerning individual urothelial cell cytomorphology when the cells are stained. The significance of the large number of anti-hTERT-positive but cytology-negative cases in our study is uncertain.

Silencing of keratin 17 by lentivirus-mediated short hairpin RNA inhibits the proliferation of PANC-1 human pancreatic cancer cells

Keratin 17 (KRT17) has been demonstrated to be a potential biological marker for the prediction of prognosis in particular types of cancer. The aim of the present study was to investigate the molecular mechanisms underlying the function of KRT17 in the pancreatic cancer (PAC) cell line PANC-1 and the potential of KRT17 as a therapeutic target for PAC. KRT17 expression levels were analyzed using quantitative PCR and compared with histological data using bioinformatics tools in PAC samples and three human PAC cell lines. Cell proliferation was determined using an MTT assay, in addition to cell cycle distribution and apoptosis analysis using flow cytometry, colony formation assay using Giemsa staining and cell motility analysis using a Transwell migration assay. Tumor growth was evaluated in vivo in nude mice. The expression levels of a number of signaling molecules were measured to establish the potential mechanism by which silencing KRT17 expression affected PAC PANC-1 cells. Increased levels of KRT17 expression were observed in human PAC compared with normal tissues, as well as in three human PAC cell lines (MIA PaCa-2, PANC-1 and KP-3 cells) compared with the H6c7 human immortal pancreatic duct epithelial cell line. High expression levels of KRT17 in PAC samples were associated with poor overall survival (P=0.036) and disease-free survival (P=0.017). Lentivirus-mediated KRT17 silencing inhibited cell proliferation, colony formation and migration, but promoted apoptosis and resulted in cell cycle arrest in the G₀/G₁ phase in PANC-1 cells. In addition, KRT17 knockdown inhibited in vivo tumor growth. KRT17 knockdown induced dysregulation of ERK1/2 and upregulation of the pro-apoptotic Bcl-2 protein Bad. In conclusion, the present study demonstrated that elevated KRT17 levels are positively associated with pancreatic cancer progression; KRT17 knockdown suppressed cell growth, colony formation, migration and tumor growth, and induced apoptosis and cell cycle arrest, affecting ERK1/2/Bad signaling. Therefore, the results of the present study suggested that KRT17 may be a potential target for the treatment of pancreatic cancer.