Detection of CK19 mRNA Using One-step Nucleic Acid Amplification (OSNA) in Prostate Cancer: Preliminary Results

Evaluation of Cytokeratin-7 and Cytokeratin-19 Expression Relationship with Gleason Score in Prostatic Adenocarcinoma

Background & Objective

Prostatic adenocarcinoma (PAC) is one of the most common tumors worldwide. Immunohistochemical expression of cytokeratins has been evaluated in the diagnosis and prognosis of tumors. The aim of the present study is the evaluation of Cytokeratin-7 (Ck-7) and Cytokeratin-19 (Ck-19) expression and its relationship with Gleason score in patients with PAC.

Methods

In this cross-sectional study, 78 samples from 78 patients with PAC referred to Mostafa Khomeini Hospital were gathered. Samples were immunohistochemically stained by Ck-7 and Ck-19 markers. The percentage of each marker in tumor cells was determined, and its relationship with Gleason scores and Gleason grade groups was analysed by SPSS version 24.

Results

The expression of Ck-7 and Ck-19 were seen in 37.2% and 82.1% of samples, respectively. The mean of Ck-7 expression in tumor cells was 4.98%±7.19 (ranged 0 to 26%), while the mean of Ck-19 expression was 41.02%±23.36 (ranged 0 to 78%). There was no relationship between Ck-7 expression with Gleason scores and Gleason grade groups. However, Ck-19 expression was increased in higher Gleason scores and Gleason grade groups (P<0.001). No relationship was found between age and Ck-7 (P=0.309) and Ck-19 (P=0.375).

Conclusion

The Ck-7 expression in PAC samples is weak and focal and had no relationship with the Gleason scores and Gleason grade groups. However, Ck-19 expression in PAC was high and was associated with tumor dedifferentiation of samples. There was no relationship between the expression of both markers with the patient's age.

Sentinel Lymph Node Biopsy in Prostate Cancer: An Overview of Diagnostic Performance, Oncological Outcomes, Safety, and Feasibility

Sentinel node biopsy (SNB) for prostate cancer (PCa) represents an innovative technique aimed at improving nodal staging accuracy. The routinary adoption of this procedure in patients undergoing radical prostatectomy (RP) might be crucial to identify candidates who could effectively benefit from extensive pelvic lymph nodal dissection (ePLND). Despite some promising results, SNB for PCa is still considered experimental due to the lack of solid evidence and procedural standardization. In this regard, our narrative review aimed to analyze the most recent literature in this field, providing an overview of both the diagnostic accuracy measures and the oncological outcomes of SNB.

One step nucleic acid amplification (OSNA) for detection of lymph node metastasis during robotic radical prostatectomy for prostate cancer: A pilot study

Introduction: The OSNA technique is based on reverse transcription loop-mediated DNA amplification for the detection of cytokeratin 19 (CK19) messen-ger RNA (mRNA). The purpose of our paper, which represents the first study in the literature, is to test the accuracy of this method in the detection of lymph node metastases in patients undergoing robotic radical prostatectomy with lymph node dis-section. Methods: Our cohort consisted of patients that have undergone robotic radical prostatectomy with extended lymph node dissec-tion. Lymph nodes were evaluated with imprint technique and then with frozen section examination. The remaining tissue was evaluated by OSNA method. Lymph nodes were defined as ‘neg-ative’ or ‘positive’ according to mRNA copy number. Results: 7 patients and 25 lymph nodes were included in our cohort. Two patients were found negative with all pathology methods. In one patient the standard stains revealed a suspi-cious outcome but it was positive for micrometastasis with OSNA. In another patient the outcome was positive for standard stains and negative for OSNA. Finally, 2 patients were found positive for OSNA and negative for imprint methods. Conclusions: One Step Nucleic Acid Amplification (OSNA) method using CK19 seems to fail in detection of lymph node metastases in prostate cancer patients undergoing radical prostatectomy and lymph node dissection.

One-step nucleic acid amplification for intraoperative diagnosis of lymph node metastasis in lung cancer patients: a single-center prospective study

One-step nucleic acid amplification (OSNA) is a rapid intraoperative molecular detection technique for sentinel node assessment via the quantitative measurement of target cytokeratin 19 (CK19) mRNA to determine the presence of metastasis. It has been validated in breast cancer but its application in lung cancer has not been adequately investigated. 214 LNs from 105 patients with 100 primary lung cancers, 2 occult primary lung tumors, and 3 metastatic lung tumors, who underwent surgical lung resection with LN dissection between February 2018 and January 2020, were assessed. Resected LNs were divided into two parts: one was snap-frozen for OSNA and the other underwent rapidly frozen histological examination. Intraoperatively collected LNs were evaluated by OSNA using loop-mediated isothermal amplification and compared with intraoperative pathological diagnosis as a control. Among 214 LNs, 14 were detected as positive by OSNA, and 11 were positive by both OSNA and intraoperative pathological diagnosis. The sensitivity and specificity of OSNA was 84.6% and 98.5%, respectively. The results of 5 of 214 LNs were discordant, and the remainder all matched (11 positive and 198 negative) with a concordance rate of 97.7%. Although the analysis of public mRNA expression data from cBioPortal showed that CK19 expression varies greatly depending on the cancer type and histological subtype, the results of the five cases, except for primary lung cancer, were consistent. OSNA provides sufficient diagnostic accuracy and speed and can be applied to the intraoperative diagnosis of LN metastasis for non-small cell lung cancer.

Effective Diagnosis of Prostate Cancer Based on mRNAs From Urinary Exosomes

Background

Novel non-invasive biomarkers are urgently required to improve the diagnostic sensitivity and specificity of prostate cancer (PCa). Therefore, the diagnostic value of following candidate genes (ERG, PCA3, ARV7, PSMA, CK19, and EpCAM) were estimated by testing mRNAs from urinary exosomes of patients with primary PCa.

Methods

Exosomes were obtained using size-exclusion chromatography (SEC), out of which RNAs were extracted, then analyzed by quantitative reverse transcription-polymerase chain reaction according to manufacturer's protocol.

Results

The expression of urinary exosomal ERG, PCA3, PSMA, CK19, and EpCAM were significantly increased in patients with PCa compared with healthy males. In addition, the levels of urinary exosomal ERG, ARV7, and PSMA were intimately correlated with the Gleason score in PCa patients (P < 0.05). The receiver operating characteristic curves (ROCs) showed that urinary exosomal ERG, PCA3, PSMA, CK19, and EpCAM were able to distinguish patients with PCa from healthy individuals with the area under the curve (AUC) of 0.782, 0.783, 0.772, 0.731, and 0.739, respectively. Urinary exosomal PCA3 and PSMA distinguished PCa patients from healthy individuals with an AUC of 0.870. Combination of urinary exosomal PCA3, PSMA with serum PSA and PI-RADS achieved higher AUC compared with PSA alone (0.914 and 0.846, respectively). Kaplan-Meier curves demonstrated that PCA3, ARV7, and EpCAM were associated in androgen-deprivation therapy (ADT) failure time which is defined as from the initiation of ADT in hormone-sensitive stage to the development of castration-resistant prostate cancer.

Conclusion

These findings suggested that mRNAs from urinary exosomes have the potential in serving as novel and non-invasive indicators for PCa diagnosis and prediction.

Application of One-Step Nucleic Acid Amplification (OSNA) in different cancer entities and usefulness in prostate cancer: a systematic review

Background

Lymph node (LN) status is a key prognostic factor in the decision-making process of different cancer entities, including prostate cancer (PCa). Sectioning and haematoxylin and eosin (H&E) staining technique remain the gold standard for the evaluation of LN metastases despite some limitations, especially low sensitivity in detecting an accurate tumour burden within the LN, as well as a subjective and time-consuming result. One-step nucleic acid amplification (OSNA) quantifies mRNA copies of cytokeratin 19 (CK19) in a fast, objective, automated, and reproducible way, raising a general interest to explore its utility for lymphatic metastasis identification in different malignancies.

Methods

To present the latest evidence related to the detection of LN metastases in several tumours by using OSNA compared with the conventional H&E method, a systematic review of articles published since March 2021 was conducted using PubMed, Cochrane Library, and Web of Science databases. References from primary papers and review articles were checked to obtain further potential studies. Our procedure for evaluating records identified during the literature search followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses criteria. With the aim to design and justify future clinical routine use of OSNA in PCa, novel PCa evidence has been included in this review for the first time.

Results

Twenty five studies were included. LN from six different groups of tumours: breast, gastrointestinal, gynecological, lung, head and neck and prostate cancers has been assessed. OSNA was compared with post-operative formalin-fixed paraffin-embedded tissue sections with H&E staining as the reference standard. Contingency tables were created, and concordance rate, sensitivity, specificity and predictive values were reported. Seventeen studies analysed the discordant cases using different techniques.

Conclusion

OSNA method has a high diagnostic accuracy for the detection of LN metastases in several CK19 expressing tumours. Available evidence might encourage future investigations about its usage in PCa patients to improve LN staging and prognosis.

Molecular Cytology by One-Step Nucleic Acid Amplification (OSNA) Assay of Peritoneal Washings during D2 Gastrectomy in Advanced Gastric Cancer Patients: Preliminary Results

The presence of peritoneal free cancer cells (FCC) in gastric cancer (GC) patients is a poor prognostic factor. D2 gastrectomy may induce exfoliated FCC spread from the primary tumour or involved lymph nodes (LN). Conventional cytology for FCC detection has several limitations, whereas prophylactic use of extensive intraoperative peritoneal lavage (IPL) does not improve survival. A prospective single-arm observational study was conducted to verify whether D2 gastrectomy causes an intraoperative increase of FCC in peritoneal fluid. Twenty-seven GC patients underwent D2 gastrectomy, followed by objective quantitative measurements of CK19 mRNA level reflecting FCC with One-Step Nucleic Acid Amplification (OSNA) assay. The IPL with 3000 mL of saline was performed twice: (1) after gastrectomy with D2 lymphadenectomy and (2) after alimentary tract reconstruction. The IPL samples were analysed by initial cytology and four (1-4) consecutive OSNA assays. Initial OSNA measurement (1) revealed positive results (≥24.6 cCP/μL) in 7 (29.6%) patients. Subsequent OSNA measurements showed a significant decrease in the FCC level after D2 gastrectomy (1 vs. 2; p = 0.0012). The first IPL induced a non-significant increase in the FCCs (2 vs. 3, p = 0.3300), but the second IPL reversed it to normal levels (3 vs. 4, p = 0.0.0574). The OSNA assay indicates a temporal intraoperative increase in the peritoneal FCC in advanced GC patients undergoing D2 gastrectomy. Two consecutive IPLs are necessary to reverse the increase of CK19 mRNA level in peritoneal washings.

The serum CK17 and CK19 expressions in cervical cancer patients and their prognostic value

OBJECTIVE

This study was designed to quantify the serum CK17 and CK19 expressions in cervical cancer (CC) patients and determine their predictive value.

METHODS

A total of 124 CC patients admitted to Zhejiang North Medical Center (Huzhou Central Hospital) between November 2014 and November 2017 were recruited for the study and placed in a research group (the Res group), and 99 healthy individuals during the same period were also recruited for the study and placed in a control group (the Con group). Their serum CK17 and CK19 expressions were quantified, and the diagnostic significance of the two for CC was analyzed. Additionally, the patients were followed up for three years. The patients were then assigned to favorable and unfavorable prognosis groups, and then the predictive significance of CK17 and CK19 for such patients was evaluated.

RESULTS

The Res group presented significantly higher serum CK17 and CK19 expression levels than the Con group, and the two factors were positively associated. Additionally, neither of the AUCs for serum CK17 and CK19 in identifying CC were less than 0.800, and the AUC of the combination of the two in identifying it was not smaller than 0.900. The AUC of the combination of serum CK17 and CK19 in identifying unfavorable CC prognoses was approximate 0.850, and high expression levels CK17 and CK19 were closely related with low three-year overall survival rates.

CONCLUSION

Serum CK17 combined with serum CK19 is of great diagnostic and predictive significance for CC.

Diagnostic and prognostic impact of cytokeratin 19 expression analysis in human tumors: a tissue microarray study of 13,172 tumors

To evaluate cytokeratin 19 (CK19) expression in normal and cancerous tissues, 15,977 samples from 122 tumor types and 608 samples of 76 normal tissue types were analyzed by immunohistochemistry (IHC). In normal tissues, CK19 expression occurred in epithelial cells of most glandular organs but was strictly limited to the basal cell layer of nonkeratinizing squamous epithelium and absent in the skin. CK19 expression in ≥90% of cases was seen in 34% of the tumor entities including the adenocarcinomas of the pancreas (99.4%), colorectum (99.8%), esophagus (98.7%), and stomach (97.7%), as well as breast cancer (90.0%-100%), high-grade serous (99.1%) or endometrioid (97.8%) ovarian cancer, and urothelial carcinoma (92.6%-100%). A low CK19 positivity rate (0.1-10%) was seen in 5 of 122 tumor entities including hepatocellular carcinoma and seminoma. A comparison of tumor versus normal tissue findings demonstrated that upregulation and downregulation of CK19 can occur in cancer and that both alterations can be linked to unfavorable phenotypes. CK19 downregulation was linked to high grade (p = 0.0017) and loss of estrogen receptor- and progesterone receptor-expression (p < 0.0001 each) in invasive breast carcinoma of no special type. CK19 upregulation was linked to nodal metastases in neuroendocrine tumors and papillary thyroid carcinomas (p < 0.05 each) and to poor grade in clear cell renal cell carcinoma (p < 0.05). CK19 upregulation was particularly common in squamous cell carcinomas. We concluded that CK19 IHC might separate primary liver cell carcinoma from liver metastases, seminoma from other testicular tumors, and helps in the detection of early neoplastic transformation in squamous epithelium.

Ultrastaging Using Ex Vivo Sentinel Lymph Node Mapping and One-Step Nucleic Acid Amplification (OSNA) in Gastric Cancer: Experiences of a European Center

Simple Summary

In this study, the effectiveness of One-step nucleic acid amplification (OSNA) in combination with ex vivo SLN mapping is compared with conventional histology including immunohistochemistry. OSNA lymph node evaluation has been performed in 41 gastric cancer cases. It showed a high effectiveness with sensitivity, specificity, and accuracy rates of 85.4%, 93.5%, and 92.4%, respectively The LN status could be predicted in 40 cases and led to upstaging in three cases (14%). The OSNA method proved its potential to increase the sensitivity of metastases detection.

Abstract

Background: In this study, the effectiveness of One-step nucleic acid amplification (OSNA) in combination with ex vivo SLN mapping is compared with conventional histology including immunohistochemistry. Methods: LNs were retrieved from gastrectomy specimens in an unfixed state. After ex vivo SLN mapping using methylene-blue, LNs were sliced to provide samples for histology and OSNA. Results: In total, 334 LNs were retrieved in the fresh state from 41 patients. SLN detection was intended in 40 cases but was successful in only 29, with a correct LN status prediction in 23 cases (79%). Excluding one case out of 41 with a failure likely caused by a processing error, OSNA showed a high effectiveness with sensitivity, specificity, and accuracy rates of 85.4%, 93.5%, and 92.4%, respectively. The LN status could be predicted in all but one case, in which the single positive LN was not eligible for OSNA testing. Moreover, OSNA evaluation led to upstaging from N0 to N+ in three cases (14%). Conclusion: The ex vivo SLN protocol used resulted in a relatively poor detection rate. However, the OSNA method was not hampered by this detection rate and proved its potential to increase the sensitivity of metastases detection.

Evaluation of Fast Molecular Detection of Lymph Node Metastases in Prostate Cancer Patients Using One-Step Nucleic Acid Amplification (OSNA)

Background: In clinical routine, only fractions of lymph nodes (LNs) are examined histopathologically, often resulting in missed (micro-)metastases and incorrect staging of prostate cancer (PCa). One-step nucleic acid amplification (OSNA) analyzes the entire LN by detecting cytokeratin 19 (CK19) mRNA as a surrogate for LN metastases requiring less effort than conventional biomolecular techniques. We aimed to evaluate performance of OSNA in detecting sentinel LN (SLN) metastases in PCa. Methods: SLNs (n = 534) of 64 intermediate- or high-risk PCa patients undergoing radical prostatectomy with extended and sentinel-guided lymphadenectomy were cut into slices and alternatingly assigned to OSNA and histopathology (hematoxylin-eosin staining, CK19, and CK AE1/AE3 immunohistochemistry). Sensitivity and specificity of OSNA and concordance and measure of agreement (Cohen's kappa (κ)) between OSNA and histopathology were assessed. Results: Histopathology revealed metastases in 76 SLNs. Sensitivity and specificity of OSNA were 84.2% and 96.1%, respectively. Discordant results were recorded for 30 of 534 SLNs, revealing high concordance (94.4%). Twenty-four discordant cases were classified as micrometastases, indicating a possible allocation bias. In 18 cases, positive results were conferred only by OSNA resulting in seven LN-positive patients who were missed by histopathology. Overall, the level of agreement was high (κ = 0.78). Conclusions: OSNA provided a diagnosis that was as least as accurate as detailed histological examination and might improve LN staging in PCa.

Rapid Detection of Free Cancer Cells in Intraoperative Peritoneal Lavage Using One-Step Nucleic Acid Amplification (OSNA) in Gastric Cancer Patients

Cytokeratin-19 (CK19) has been proven to be commonly expressed by cancer cells in a variety of solid tumors and may serve as a suitable marker of metastases in gastric cancer (GC). Since objective assessment of peritoneal lavage or fluid for free cancer cells (FCC) is essential for clinical decision making in patients with GC, it is important to develop a quantitative and reproducible method for such evaluation. We assessed the possible application of One-Step Nucleic Acid amplification (OSNA) assay as a rapid method for FCC detection in intraoperative peritoneal lavage or fluid of GC patients. Seventy-eight intraoperative peritoneal lavage or fluid samples were eligible for the analysis by conventional cytology and OSNA examination. The concentration of CK19 mRNA in intraoperative peritoneal lavage and fluid was compared with the conventional cytological assessment. CK19 mRNA concentration was detected by OSNA assay. For peritoneal lavage samples, sensitivity and specificity were 83.3% and 87.8%, respectively. In peritoneal fluid, significantly higher CK19 values were observed in patients with serosal infiltration (medians: 100 copies/µL vs. 415.7 copies/µL; p = 0.0335) and lymph node metastases (medians: 2.48 copies/µL vs. 334.8 copies/µL). OSNA assay turns out to be an objective, fast, and reproducible quantitative method of FCC assessment.