Performance evaluation of serum PIVKA-II measurement using HISCL-5000 and a method comparison of HISCL-5000, LUMIPULSE G1200, and ARCHITECT i2000

Tumor biomarkers for diagnosis, prognosis and targeted therapy

Tumor biomarkers, the substances which are produced by tumors or the body's responses to tumors during tumorigenesis and progression, have been demonstrated to possess critical and encouraging value in screening and early diagnosis, prognosis prediction, recurrence detection, and therapeutic efficacy monitoring of cancers. Over the past decades, continuous progress has been made in exploring and discovering novel, sensitive, specific, and accurate tumor biomarkers, which has significantly promoted personalized medicine and improved the outcomes of cancer patients, especially advances in molecular biology technologies developed for the detection of tumor biomarkers. Herein, we summarize the discovery and development of tumor biomarkers, including the history of tumor biomarkers, the conventional and innovative technologies used for biomarker discovery and detection, the classification of tumor biomarkers based on tissue origins, and the application of tumor biomarkers in clinical cancer management. In particular, we highlight the recent advancements in biomarker-based anticancer-targeted therapies which are emerging as breakthroughs and promising cancer therapeutic strategies. We also discuss limitations and challenges that need to be addressed and provide insights and perspectives to turn challenges into opportunities in this field. Collectively, the discovery and application of multiple tumor biomarkers emphasized in this review may provide guidance on improved precision medicine, broaden horizons in future research directions, and expedite the clinical classification of cancer patients according to their molecular biomarkers rather than organs of origin.

Reference Range of Vitamin K Evaluating Indicators in Chinese Childbearing Women

BACKGROUND

Vitamin K is an essential fat-soluble vitamin for the human body and its functions, such as promoting blood coagulation, bone health and preventing atherosclerosis, have attracted increasing attention. However, there is no recognized indicator and corresponding reference range for evaluating vitamin K status of different populations at present. The aim of this study is to establish a reference range for vitamin K evaluating indicators in healthy women of childbearing age in China.

METHODS

The population sample in this study was from the Chinese Adult Chronic Disease and Nutrition Surveillance (CACDNS) 2015-2017. A total of 631 healthy women of childbearing age (18-49 years) were included using a series of strict inclusion and exclusion criteria. The concentrations of VK1, MK-4 and MK-7 in serum were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The other commonly-reported indicators evaluating vitamin K nutritional status, including undercarboxylated osteocalcin (ucOC), osteocalcin (OC), matrix Gla protein (MGP), desphosphorylated undercaboxylated MGP (dp-ucMGP) and protein induced by vitamin K absence II (PIVKA-II), were measured by enzyme-linked immunosorbent assay (ELISA). The reference range was obtained by calculating the 2.5% to 97.5% interval of the vitamin K evaluating indicators in the reference population.

RESULTS

The reference ranges of VK1, MK-4 and MK-7 in serum were 0.21-3.07 ng/mL, 0.02-0.24 ng/mL and 0.12-3.54 ng/mL, respectively. The reference ranges of ucOC, %ucOC, dp-ucMGP and PIVKA-II were 1.09-2.51 ng/mL, 5.80-22.78%, 2.69-5.88 ng/mL and 3.98-8.40 ng/mL, respectively. The cut-off values that can be used to evaluate subclinical vitamin K deficiency were as follows: VK1 < 0.21 ng/mL, MK-7 < 0.12 ng/mL, ucOC > 2.51 ng/mL, %ucOC > 22.78%, dp-ucMGP > 5.88 ng/mL and PIVKA-II > 8.40 ng/mL.

CONCLUSION

The reference range of VK1, MK-4, MK-7 and vitamin K-related indicators for healthy women of childbearing age established in this study could be used to assess the nutritional and health status of this population.

Cutoff values of protein induced by vitamin K absence or antagonist II for diagnosing hepatocellular carcinoma

Protein induced by vitamin K absence or antagonist II (PIVKA-II) is a promising serum marker for hepatocellular carcinoma (HCC). There are limited data on its cutoff value in HCC for Taiwanese cirrhosis patients. This study aimed to investigate the diagnostic value of PIVKA-II levels in patients with suspected HCC. In total, 88 patients with chronic hepatitis and suspected HCC by ultrasound, elevated α-fetoprotein (AFP) or PIVKA-II levels were consecutively enrolled. Their baseline characteristics and findings on dynamic phases of computed tomography (CT) or magnetic resonance imaging (MRI) were examined. Sixty participants had cirrhosis and 34 had HCC. The median levels of PIVKA-II in non-cirrhosis and cirrhosis patients without or with HCC were 28.0, 48.0, and 847.0 mAU/mL, respectively. The optimal cutoff value of PIVKA-II in predicting HCC was 78.0 mAU/mL. Combining AFP with PIVKAII mildly increased its diagnostic performance for HCC, yielding higher specificity and positive predictive value. Significant factors predicting HCC in multivariate regression analysis were PIVKA >78.0 mAU/mL and fatty liver. Monitoring PIVKA-II level is suitable for noninvasively assessing HCC in patients with chronic hepatitis, particularly with AFP.

Performance evaluation of thrombus molecular markers thrombomodulin, thrombin-antithrombin complex, plasmin-α2-plasmin inhibitor complex, and tissue plasminogen activator-inhibitor complex by a chemiluminescence analyzer

OBJECTIVE

To comprehensively evaluate the primary performance regarding the task of detecting thrombomodulin (TM), thrombin-antithrombin complex (TAT), plasmin-α2-plasmin inhibitor complex (PIC), and tissue plasminogen activator/plasminogen activator inhibitor-1 complex (t-PAIC) by Sysmex HisCL5000 high sensitivity chemiluminescence analyzer.

METHODS

The performance of the chemiluminescence analyzer was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) documents for in-batch precision, daytime precision, carryover rate, linearity, and reference range.

RESULTS

The intra-batch and inter-day variation coefficients of the test items were all less than 5 %, and the contamination rate of each index was less than 10 %. The linear verification analysis showed that the correlation coefficients of TM, TAT, PIC, and t-PAIC were 0.9968, 0.9988, 0.9981, and 0.9930, respectively. The project recommended reference range was applicable to our laboratory.

CONCLUSION

The high-sensitivity chemiluminescence analyzer has good performance in the detection of TM, TAT, PIC, and t-PAIC and is suitable for the detection of clinical specimens. HIPPOKRATIA 2022, 26 (2):78-82.

The clinical application of PIVKA-II in hepatocellular carcinoma and chronic liver diseases: A multi-center study in China

BACKGROUND

Due to the absence of specific symptoms and low survival rate, efficient biomarkers for hepatocellular carcinoma (HCC) diagnosis are urgently required. The purpose of this study was to evaluate the diagnostic performance of protein induced by vitamin K absence or antagonist-II (PIVKA-II) and to determine the optimal cutoff values for HBV infection-related HCC.

METHODS

We conducted a cross-sectional, multi-center study in China to ascertain the cutoff value for HCC patients in the context of CHB- and HBV-related cirrhosis. The receiver operating characteristic curve (ROC) and the area under the curve (AUC) were used to evaluate the diagnostic performance of PIVKA-II.

RESULTS

This study enrolled 784 subjects and demonstrated that PIVKA-II had a sensitivity of 84.08% and a specificity of 90.43% in diagnosis HCC from chronic liver diseases. PIVKA-II at a cutoff of 37.5 mAU/mL yielded an AUC of 0.9737 (sensitivity 91.78% and specificity 96.30%) in discriminating HCC from chronic hepatitis B (CHB) patients. PIVKA-II at a cutoff of 45 mAU/mL yielded an AUC of 0.9419 (sensitivity 77.46% and specificity 95.12%) in discriminating HCC- from HBV-related cirrhosis patients. Furthermore, using a cutoff value of 40 mAU/mL for PIVKA-II as an HCC marker, only 4.81% (15/312) was positive in chronic hepatitis and 12.80% (37/289) in cirrhosis patients, revealing the satisfactory specificity of PIVKA-II in chronic liver disease of different etiologies.

CONCLUSION

Our data indicated that PIVKA-II had satisfactory diagnostic efficiencies and could be used as a screening or surveillance biomarker in HCC high-risk population.

A performance evaluation of chemiluminescence enzyme immunoassays on the Sysmex CN-6500 haemostasis analyser

Background

The Sysmex CN‐6500 is a new haemostasis analyser with an integrated immunoassay module that performs chemiluminescence enzyme assay (CLEIA) in addition to coagulation, turbidimetric, chromogenic and platelet aggregation tests.

Aims

To evaluate the analytical performance of the CN‐6500 against the predicate device (Sysmex HISCL‐800) for soluble thrombomodulin (TM), thrombin‐antithrombin (TAT), tissue plasminogen activator/plasminogen activator inhibitor 1 complex (tPAI‐C) and plasmin α2 plasmin inhibitor complex (PIC) assays.

Methods

Imprecision was assessed by testing two levels of quality control plasmas 10 times on 5 separate days. Comparability was studied in 230 plasmas from normal donors (n = 30), patients with suspected disseminated intravascular coagulation (DIC, n = 100), sepsis (n = 20) or liver disease (n = 20), lipaemic (n = 20), haemolysed (n = 20) and icteric samples (n = 20). Limit of detection, limit of quantitation and linearity were determined by testing serial dilutions of normal plasma. Sample carryover was assessed by testing samples with high and low normal levels of the analytes concerned.

Results

The CN‐6500 performed 21 CLEIA tests per hour, while simultaneously performing coagulation tests. Acceptable between‐run imprecision was obtained using commercial controls with normal and high activity for each analyte (%CV <4%), for all four assays. Excellent linearity was observed (slope 0.89‐1.03; r² >0.99) across the measurement range. The lower limits of detection and quantitation were as follows: TM <0.3/0.6 TU/ml, TAT >0.1/<0.2 ng/ml, PIC <0.004/<0.008 µg/ml and tPAI‐C < 0.01/<0.1 ng/ml, respectively. All four assays showed excellent correlation between analysers and were unaffected by haemolysis, icterus or lipaemia. No carryover was observed.

Conclusions

Our data demonstrate that the performance of the CLEIA assays on the CN‐6500 is comparable to that of a stand‐alone immunoassay analyser.

PIVKA-II: A biomarker for diagnosing and monitoring patients with pancreatic adenocarcinoma

BACKGROUND

Pancreatic adenocarcinoma (PDAC) is an incurable cancer without adequate tumor markers. Our previous study has showed a better diagnostic performance of Protein Induced by Vitamin K Absence II (PIVKA-II) compared to currently used PDAC biomarkers. To corroborate our previous data with a larger sample size and to assess a possible role of PIVKA-II in predicting surgical success. Additionally, to further evaluate the hypothesis of a direct PIVKA-II production by PDAC cells, we examined PIVKA-II tissue expression in a case of PDAC using immunofluorescence.

METHODS

We enrolled 76 newly diagnosed PDAC patients and selected 11 patients to determine PIVKA-II levels also after surgical resection. An immunofluorescence (IF) study of PIVKA-II tissue expression was carried out in one of them. PIVKA-II serum values were measured by chemiluminescent enzyme immunoassay method (CLEIA) on LUMIPULSE G1200 (Fujirebio-Europe, Belgium).

RESULTS

PIVKA-II serum levels were above the cut-off at baseline in 71 patients (94%) with a median value of 464 mAU/Ml (range 27-40783 mAU/mL); the sensitivity and specificity were 78.67% and 90.67% respectively. Patients with pre-operative PIVKA-II positivity showed a significant decrease (P < 0.015) of median PIVKA-II serum concentrations after surgery: 820 (91-40783) mAU/mL at diagnosis vs 123 (31-4666) mAU/mL post-operatively. IF assay on PDAC sections demonstrated PIVKA-II expression in cancer cells.

CONCLUSION

These data are the first showing a decreased PIVKA-II serum levels after surgery in PDAC patients and reporting PIVKA-II expression in PDAC tissue. Further studies are needed to confirm these findings and to determine PIVKA-II usefulness in diagnosing and monitoring PDAC patients.

Vitamin K Status in Adherent and Non-Adherent Patients with Phenylketonuria: A Cross-Sectional Study

This is the first study to evaluate vitamin K status in relation to dietary intake and phenylalanine dietary compliance in patients with phenylketonuria (PKU). The dietary and PKU formula intake of vitamin K was calculated in 34 PKU patients, with vitamin K status determined by the measurement of prothrombin induced by vitamin K absence (PIVKA-II). Blood phenylalanine concentrations in the preceding 12 months were considered. There were significantly more phenylalanine results exceeding 6 mg/dL in patients with normal PIVKA-II concentrations than in those with abnormal PIVKA-II levels (p = 0.035). Similarly, a higher total intake of vitamin K and dietary vitamin intake expressed as μg/day (p = 0.033 for both) and %RDA (p = 0.0002 and p = 0.003, respectively) was observed in patients with normal PIVKA-II levels. Abnormal PIVKA-II concentrations were associated with a lower OR (0.1607; 95%CI: 0.0273–0.9445, p = 0.043) of having a median phenylalanine concentration higher than 6 mg/dL. In conclusion, vitamin K deficiency is not uncommon in phenylketonuria and may also occur in patients with adequate vitamin K intake. PKU patients with better dietary compliance have a higher risk of vitamin K deficiency. The present findings highlight the need for further studies to re-evaluate dietary recommendations regarding vitamin K intake, both concerning formula-based and dietary consumption of natural products.

Laboratory assessment of vitamin K status

Vitamin K is required for the ɣ-carboxylation of specific glutamic acid residues within the Gla domain of the 17 vitamin K-dependent proteins (VKDPs). The timely detection and correction of vitamin K deficiency can protect against bleeding. Vitamin K also plays a role in bone metabolism and vascular calcification. Patients at increased risk of vitamin K deficiency include those with a restricted diet or malnutrition, lipid malabsorption, cancer, renal disease, neonates and the elderly. Coagulation assays such as the prothrombin time have been used erroneously as indicators of vitamin K status, lacking sufficient sensitivity and specificity for this application. The measurement of phylloquinone (K1) in serum is the most commonly used marker of vitamin K status and reflects abundance of the vitamin. Concentrations <0.15 µg/L are indicative of deficiency. Disadvantages of this approach include exclusion of the other vitamin K homologues and interference from recent dietary intake. The cellular utilisation of vitamin K is determined through measurement of the prevalence of undercarboxylated VKDPs. Most commonly, undercarboxylated prothrombin (Protein Induced by Vitamin K Absence/antagonism, PIVKA-II) is used (reference range 17.4–50.9 mAU/mL (Abbott Architect), providing a retrospective indicator of hepatic vitamin K status. Current clinical applications of PIVKA-II include supporting the diagnosis of vitamin K deficiency bleeding of the newborn, monitoring exposure to vitamin K antagonists, and when used in combination with α-fetoprotein, as a diagnostic marker of hepatocellular carcinoma. Using K1 and PIVKA-II in tandem is an approach that can be used successfully for many patient cohorts, providing insight into both abundance and utilisation of the vitamin.

Evaluation of the clinical performance of the HISCL-5000 analyzer in the detection of Krebs von den Lungen-6 antigen and its diagnostic value in interstitial lung disease

Background

The sputum saccharide chain antigen (Krebs von den Lungen‐6 [KL‐6]) is a serum biomarker of lung injury. We aimed to evaluate the clinical performance of the automated immunoassay analyzer HISCL‐5000 in detecting KL‐6 by comparing it with LUMIPULSE G1200 and determine the diagnostic value of KL‐6 in interstitial lung disease (ILD).

Methods

A total of 145 serum samples from patients were tested using the two automated immunoassay analyzers in parallel.

Results

With a cutoff level of 500 U/mL, comparing the two systems, the agreement, sensitivity, specificity, and kappa value were 99.20%, 100%, 98.63%, and 0.984 (95% CI, 0.952‐1.000), respectively. Spearman's correlation and ICC showed that there was a strong correlation between serum KL‐6 levels measured by the two systems (r_S = .991 [95% CI, 0.981‐0.995], ICC = 0.984 [95% CI, 0.978‐0.989], P < .01). The clinical diagnosis agreement rate in both systems was >80%. The kappa value was 0.707 (95% CI, 0.582‐0.832; SYSTEM B) and 0.707 (95% CI, 0.588‐0.826; SYSTEM A). The KL‐6 level in the ILD group (1339.5, 662.5‐2363) was significantly higher than that in the non‐ILD groups (252, 158.5‐353; Mann‐Whitney U = 381.5, P < .01), and the KL‐6 level (1558, 726‐2772.5) in the ILD group detected by SYSTEM A was significantly higher than that in the lung cancer group (339, 207‐424), other respiratory disease group (249, 194‐366), and control group (198, 131.5‐297; Kruskal‐Wallis H = 63.19, P < .01).

Conclusions

HISCL‐5000 showed well‐concordant results with those of HISCL‐5000 in the KL‐6 tests. In patients with ILD, KL‐6 showed a good diagnostic performance.

Performance evaluation of serum PIVKA-II measurement using HISCL-5000 and a method comparison of HISCL-5000, LUMIPULSE G1200, and ARCHITECT i2000

Background

Protein induced by vitamin K antagonist‐II (PIVKA‐II), in addition to alpha‐fetoprotein, is a useful tumor marker for diagnosis of hepatocellular carcinoma (HCC). We evaluated the analytical performance of the HISCL‐5000 analyzer (Sysmex Corporation) in the measurement of serum PIVKA‐II.

Methods

We evaluated the precision and linearity of PIVKA‐II assays using the HISCL‐5000 analyzer. Methods using HISCL‐5000, LUMIPULSE G1200 (Fujirebio Diagnostics), and ARCHITECT i2000 (Abbott Diagnostics) were compared according to the guidelines of the Clinical and Laboratory Standards Institute. A total of 501 subjects (median age 59 years, age range 24‐90 years) were enrolled. Among them, 335 were HCC patients, 46 were patients with non‐HCC liver disease, and 120 were healthy individuals. Non‐HCC liver disease included liver cirrhosis, chronic hepatitis, HBV or HCV carrier, hepatic adenoma, and intrahepatic cholangiocarcinoma.

Results

Repeatability (%CV) in low‐ and high‐level controls and pooled serum was 2.81%‐10.30%, and within‐laboratory precision was 4.24%‐8.86%. In a linearity test, the coefficient of determination (R²) was 0.9957, ranging from 11 to 69 897 mAU/mL. In comparison, the coefficient of correlation (r) was 0.9561‐0.9644, agreement was 93.4%‐97.6%, and the κ value was 0.855‐0.945 among the three analyzers. About 99.2% of healthy individuals and 84.8% of non‐HCC liver disease patients were below the cutoff value (40 mAU/mL) on HISCL‐5000.

Conclusions

A PIVKA‐II assay using HISCL‐5000 showed acceptable analytical performance including precision, linearity, and method comparison. This indicates that HISCL‐5000 can be potentially helpful in clinical laboratories.