High Serum KL-6 Levels Research Articles

Comparison of Clinical Features between the High and Low Serum KL-6 Patients with Acute Exacerbation of Interstitial Lung Diseases.

Background Serum Krebs von den Lungen-6 (KL-6) measurement is widely used to assess disease activity or prognosis in patients with interstitial lung diseases (ILDs). However, the clinical differences between high and low serum KL-6 levels at the time of acute exacerbation (AE) of ILD are not well known. Methods Clinical parameters including age, sex, Charlson Comorbidity Index score (CCIS), blood biomarkers, high-resolution CT findings, and disease mortality were retrospectively compared between high and low KL-6 (cutoff value: 1000 U/mL) patients at the time of diagnosis of AE of ILDs. Results Thirty-eight high serum KL-6 and 57 low serum KL-6 patients were included. There was no significant difference in 6-month mortality between them (P = 0.685), whereas serum lactate dehydrogenase was a significant predictor of 6-month mortality in the high serum KL-6 patients (odds ratio (OR): 1.006; 95% confidence interval (CI): 1.003–1.009; P < 0.001), and CCIS (OR: 1.502; 95% CI: 1.242–1.838; P < 0.001) and sex (OR: 5.751; 95% CI: 1.121–105.163; P = 0.033) were significant predictors in low serum KL-6 patients. In addition, the incidences of congestive heart failure, symptomatic chronic pulmonary disease, cerebrovascular disease, and second metastatic solid tumours were significantly higher in nonsurvivors with low serum KL-6 than in other groups (P < 0.05). Conclusions The clinical features in patients with AEs of ILDs may differ depending on the serum KL-6 level, and clinicopathological examination according to this subtyping guided by the serum KL-6 level is essential.

Characteristics and clinical significance of pulmonary function test and KL-6 in ASSD-ILD and IPF

Objective: To study the characteristics and clinical significance of pulmonary function test and kerbs von den lungen 6 (KL-6) in anti-synthetase syndrome related interstitial lung disease (ASSD-ILD) and idiopathic pulmonary fibrosis (IPF). Methods: The clinical data of 43 patients with ASSD-ILD (ASSD-ILD group) from May 2015 to May 2017 were collected retrospectively, including 12 males and 31 females, and 34 patients with IPF (IPF group) treated in the First Affiliated Hospital of Zhengzhou University during the same period, including 28 males and 6 females, were also included. The basic information, and the value of pulmonary function test [pulmonary function parameters included the forced vital capacity expressed as percent predicted (FVC%pred), the forced expiratory volume in 1 second expressed as percent predicted (FEV(1)%pred), the ratio of FVC to FEV(1) (FVC/FEV(1)), the peak expiratory flow expressed as percent predicted (PEF%pred), the forced expiratory flow at 25%, 50%, 75% of FVC as percent predicted (FEF(25)%pred, FEF(50)%pred, and FEF(75)%pred), the maximum mid-expiratory flow as percent predicted (MMEF% pred), and the diffusing capacity for carbon monoxide as percent predicted (DLCO% pred)], and serum KL-6 level in ASSD-ILD and IPF were compared. Results: The FEV(1)%pred, FEF(50)%pred, FEF(75)%pred, and MMEF%pred values in ASSD-ILD group were significantly lower than those in IPF group (all P<0.05), while the FVC% pred, FVC/FEV(1), PEF% pred, FEF(25)%pred, and DLCO% pred values in ASSD-ILD group had no significant difference compared with IPF group (all P>0.05). There was no significant difference in serum KL-6 level between ASSD-ILD group and IPF group [(1 169±911) vs (1 210±908) U/ml, t=0.62, P=0.463]. Follow-up analysis showed that the serum KL-6 level of ASSD-ILD patients who died within two years was significantly higher than that of survivors [(2 060±1 168) vs (1 042±858) U/ml, t=2.93, P=0.041]. The serum KL-6 level of patients who died within two years of IPF patients was also significantly higher than that of patients who survived [(1 767±865) vs (1 089±894) U/ml, t=2.53, P=0.026]. The serum KL-6 level in ASSD-ILD group was negatively correlated with FVC%pred (r=-0.43, P=0.004), FEV(1)%pred (r=-0.39, P=0.010) and DLCO% pred (r=-0.41, P=0.006). There was no correlation between serum KL-6 level and pulmonary function test indexes in IPF group (all P>0.05). Conclusions: There is difference in pulmonary function test between ASSD-ILD patients and IPF patients. High serum KL-6 level will be predictive of poor prognosis.

Use of serum KL-6 level for detecting patients with restrictive allograft syndrome after lung transplantation.

KL-6 is an antigen produced mainly by damaged type II pneumocytes that is involved in interstitial lung disease. Chronic lung allograft dysfunction (CLAD) after lung transplantation (LT) is a major concern for LT clinicians, especially in patients with restrictive allograft syndrome (RAS). We investigated KL-6 levels in serum and bronchoalveolar lavage fluid (BALF) as a potential biomarker of the RAS phenotype. Levels of KL-6 in serum and BALF were measured in 73 bilateral LT recipients, and patients were categorized into 4 groups: stable (ST), infection (LTI), bronchiolitis obliterans syndrome (BOS), and RAS. We also studied a healthy cohort to determine reference values for serum KL-6. The highest levels of KL-6 were found in the serum of patients with RAS (918 [487.8–1638] U/mL). No differences were found for levels of KL-6 in BALF. Using a cut-off value of 465 U/mL serum KL-6 levels was able to differentiate RAS patients from BOS patients with a sensitivity of 100% and a specificity of 75%. Furthermore, higher serum KL-6 levels were associated with a decline in Forced Vital Capacity (FVC) at 6 months after sample collection. Therefore, KL-6 in serum may well be a potential biomarker for differentiating between the BOS and RAS phenotypes of CLAD in LT recipients.

Prognostic factors for primary Sjögren's syndrome-associated interstitial lung diseases.

Interstitial lung disease (ILD) is a condition characterized by a higher mortality rate in primary Sjögren's syndrome (pSS). However, factors influencing the outcome of patients with pSS-associated ILD remain unclear. The aim of the present study was to evaluate predictive factors associated with a worse prognosis in pSS-ILD. This retrospective study included 99 consecutive patients with pSS-ILD. Clinical characteristics, laboratory findings, and pulmonary function tests at the time of diagnosis were analyzed. Chest HRCT images were reviewed by two experienced chest radiologists. Prognostic factors were assessed by univariate and multivariate analyses, using Cox proportional hazards regression model. Median age was 68 years (73% women). In the total patient population, the 5- and 10-year survival rates were 89.8% and 79.0%, respectively. Univariate analysis revealed a significant association between prognosis and age, serum Krebs von den Lungen-6 (KL-6) levels, and %FVC. None of the chest HRCT findings were related to patient outcomes. Based on multivariate analyses adjusted by age and gender, lower levels of %FVC and higher levels of KL-6 were significantly associated with poor outcomes. Using optimal cutoff levels, according to receiver operating characteristic curve analyses, KL-6 > 800 U/mL were significantly associated with worse prognosis (HR: 2.91, 95% CI: 1.04-8.10). Patients with elevated serum KL-6 levels (>800 U/mL) showed a higher mortality rate than those without elevated serum KL-6 levels (p = 0.02). Lower %FVC and higher serum KL-6 levels are predictive factors for poor outcome in patients with pSS-ILD.

MUC1/KL-6 expression confers an aggressive phenotype upon myeloma cells

The sialic glycoprotein, MUC1, is known to be involved in the pathogenesis of various types of cancers. KL-6 is one of the surface antigens of MUC1 and also a marker of interstitial pneumonitis. A fraction of patients with myeloma (3.9%) have elevated serum KL-6 levels without any evidence of interstitial pneumonitis and their myeloma cells have high MUC1 expression. We established a myeloma cell line designated EMM1 from a patient with multiple myeloma accompanied with elevated serum KL-6. EMM1 cells expressed high levels of MUC1 compared with other myeloma cell lines. Knockdown of MUC1 in EMM1 cells induced cell cycle arrest during S phase and apoptosis, suggesting that the MUC1 expression is involved in accelerated growth of EMM1 cells. RNA-seq analysis suggests that MUC1 expression activates k-ras and TNFα-induced NFκB pathways in EMM1 cells. We injected EMM1 cells subcutaneously into Rag2−/−Jak3−/− Balb/c mice to establish a mouse xenograft model. These mice had aggressive tumor growth that was accompanied by high serum KL-6 levels. In addition, MUC1 knockdown in EMM1 cells led to inhibited tumor growth. These findings demonstrate that MUC1 serves as a potential target for developing drugs for treatment of patients with KL-6+ myeloma, and EMM1 cells and EMM1-engrafted mice are useful tools for the development of such novel agents.

Prediction of therapeutic response before and during i.v. cyclophosphamide pulse therapy for interstitial lung disease in systemic sclerosis: A longitudinal observational study.

There have been no established parameters to predict responsiveness to i.v. cyclophosphamide (IVCY) pulse therapy in combination with corticosteroids in patients with interstitial lung disease (ILD) related to systemic sclerosis (SSc). This retrospective study was conducted to determine predictive factors for efficacy of IVCY at the time of before and during the treatment. Thirty-two Japanese SSc patients, ever treated for ILD with IVCY in combination with prednisolone, were analyzed retrospectively. We performed detailed time-course analyses of parameters derived from blood samples and pulmonary function tests. With the exclusion of eight unclassified patients, 24 patients were classified into 14 good responders (GR) or 10 poor responders (PR) on the basis of changes in percent predicted diffusing capacity for carbon monoxide (DLco). Pretreatment percent predicted DLco was significantly reduced in PR compared with GR. In addition, serum parameters such as Krebs von den Lungen-6 (KL-6), surfactant protein D (SP-D) and C-reactive protein were significantly higher in PR than in GR. Furthermore, our time-course analyses revealed a transient increase in serum KL-6 levels with a peak at 3 months after the first infusion of cyclophosphamide, which showed no relation to therapeutic efficacy. Moreover, continuously high serum KL-6 levels (>2000 U/mL) and rapid decrease in SP-D levels (<200 ng/mL) during IVCY were remarkably characteristic of PR and GR, respectively. ILD severity/activity before treatment and variability of serum KL-6 and SP-D levels during treatment may be useful to predict therapeutic effects of IVCY on SSc-ILD.

Digital Clubbing Is Associated with Higher Serum KL-6 Levels and Lower Pulmonary Function in Patients with Interstitial Lung Disease.

Background Although digital clubbing is a common presentation in patients with interstitial lung disease (ILD), little has been reported regarding its role in assessing patients with ILD. This study evaluated patients with ILD for the presence of clubbing and investigated its association with clinical data. Methods We evaluated patients with ILD who visited the teaching hospital at which the study was conducted, between October 2014 and January 2015. Clubbing, evaluated using a Vernier caliper for individual patients, was defined as a phalangeal depth ratio > 1. We examined the association of clubbing with clinical data. Results Of 102 patients with ILD, we identified 17 (16.7%) with clubbing. The partial pressure of oxygen in arterial blood was lower (65.2 ± 5.9 mmHg versus 80.2 ± 3.1 mmHg; p=0.03), serum Krebs von den Lugen-6 (KL-6) levels were higher (1495.0 ± 277.4 U/mL versus 839.1 ± 70.2 U/mL; p=0.001), and the percent predicted diffusing capacity of carbon monoxide was lower (50.0 ± 6.0 versus 73.5 ± 3.1; p=0.002) in these patients with clubbing. Conclusions Patients with clubbing had lower oxygen levels, higher serum KL-6 levels, and lower pulmonary function than those without clubbing.

Pre-operative evaluation of circulating KL-6 levels as a biomarker for epithelial ovarian carcinoma and its correlation with tumor MUC1 expression.

Krebs von den Lungen-6 (KL-6), a mucinous sialylated sugar chain on human mucin-1 glycoprotein (MUC1), is a diagnostic marker for interstitial lung diseases. Furthermore, elevated serum KL-6 levels have been observed in certain malignant tumor types of epithelial origin. The expression of MUC1 has been observed in patients with epithelial ovarian cancer (EOC) and is considered a potential therapeutic target. In the present study, KL-6 serum levels were investigated in patients clinically suspected of having malignant ovarian tumors. A total of 219 patients were enrolled in the study, which analyzed their serum KL-6 levels in addition to tumor expression of MUC1 using immunohistochemistry. High serum KL-6 levels were predominantly observed in patients with EOC, and did not occur in patients with benign or borderline tumors. The level of serum KL-6 was highly correlated with tumor stage, grade and histological type, and demonstrated superior sensitivity for the detection of ovarian cancer compared with that of serum cancer antigen 125. High serum KL-6 was significantly associated with shorter progression-free survival. In addition, tumor MUC1 expression status was significantly correlated with serum KL-6 levels. These data suggest that serum KL-6 may be a useful, non-invasive biomarker surrogate for tumor MUC1 expression in future clinical trials of MUC1-targeted therapy.

Prognostic Significance of a Tumor Marker Index Based on Preoperative Serum Carcinoembryonic Antigen and Krebs von den Lungen-6 Levels in Non-Small Cell Lung Cancer

Background:We retrospectively analysed the prognostic significance of a tumor marker index (TMI) based on preoperative serum carcinoembryonic antigen (CEA) and Krebs von den Lungen-6 (KL-6) levels in nonsmall cell lung cancer (NSCLC) patients.Materials and Methods:We enrolled 176 NSCLC patients who had preoperative serum CEA and KL-6 level measurements and had undergone curative surgery between 2009 and 2011.Results:The 5-year disease-specific survival of patients with high serum CEA levels was significantly poorer compared with that of patients with normal levels. The value for patients with high serum KL-6 levels was also poor. Patients with both normal serum CEA and KL-6 levels had a favourable prognosis, whereas those with both high serum CEA and KL-6 levels had a poor outcome. The5-year disease-specific survival rate was 82.9% for patients in the low TMI group compared to 47.5% in the high TMI group (p<0.01). Both univariate and multivariate analyses revealed prognostic significance for TMI.Conclusions:TMI based on preoperative serum CEA and KL-6 levels might be useful for the prediction of the prognosis of NSCLC patients.

Preoperative Serum Krebs Von Den Lungen-6 and Surfactant Protein-D Levels in Non-Small Cell Lung Cancer Patients with Interstitial Pneumonia

We retrospectively analyzed the prognostic significance of preoperative serum Krebs von den Lungen-6 (KL-6) surfactant protein-D (SP-D) levels in non-small cell lung cancer (NSCLC) patients with interstitial pneumonia (IP). We enrolled 41 NSCLC patients with IP who have undergone curative surgery. Prognostic significance of serum KL-6 and SP-D levels was examined. We found a significant relationship between serum KL-6 and SP-D levels in NSCLC patients with IP. However, the 5-year survival of patients with high serum KL-6 level was poor, whereas serum SP-D level was not related to patients’ survival. Univariate analysis revealed that there was a trend towards an association between serum KL-6 level and patients’ prognosis but this did not reach statistical significance. This might be due to small number of study patients. In conclusion, there is a possibility that serum KL-6 level is a prognostic marker regardless of the presence of IP.

Prognostic significance of preoperative serum Krebs von den Lungen-6 level in non-small cell lung cancer.

We retrospectively analyzed the prognostic significance of preoperative serum Krebs von den Lungen-6 (KL-6) level in non-small cell lung cancer (NSCLC) patients. We enrolled 175 NSCLC patients who underwent curative surgery between 2009 and 2011. We subdivided the patients into 2 groups: with and without interstitial lung disease (ILD). Prognostic significance of serum KL-6 level was examined. The 5-year survival of patients with high serum KL-6 level was poor. Multivariate analysis also revealed the prognostic significance of serum KL-6 level. Serum KL-6 level was also a prognostic factor for patients without ILD. Although the number of patients with ILD was small, in patients with ILD, there was a trend towards an association between serum KL-6 level and patients' prognosis but this did not reach statistical significance. Serum KL-6 level is a prognostic factor for resected NSCLC patients, especially patients without ILD. There is a possibility that serum KL-6 level is a prognostic marker regardless of the presence of ILD.

Segmentectomy for giant pulmonary sclerosing haemangiomas with high serum KL-6 levels

We describe a 61-year old female patient with a giant pulmonary sclerosing haemangioma (PSH) and an extremely high preoperative serum KL-6 level. During an annual health screening, the patient showed a posterior mediastinal mass on chest radiography. Chest computed tomography and magnetic resonance imaging revealed a well-circumscribed 60 mm diameter nodule with a marked contrast enhancement in the left lower lobe. The preoperative serum KL-6 level was elevated to 8204 U/ml. We performed a four-port thoracoscopic basal segmentectomy and lymph node sampling for diagnosis and therapy. The postoperative diagnosis showed PSH. The serum KL-6 level decreased dramatically with tumour resection. To the best of our knowledge, this is the first report of a patient with PSH showing a high serum KL-6 level.

Metastatic Breast Cancer Presenting as Air-space Consolidation on Chest Computed Tomography

A 56-year-old woman suffered from hepatic and bone metastases of breast cancer. Two months after starting combination chemotherapy with trastuzumab and docetaxel, air-space consolidation was observed in the right lower lung lobe on a chest computed tomography (CT) and a high serum KL-6 level was detected. Drug-induced pneumonitis with organizing pneumonia type was suspected, however, a transbronchial lung biopsy and cytological examination of the bronchoalveolar lavage fluid provided evidence of metastatic breast cancer. While the lung is a frequently affected site from metastasis of breast cancer, we report a rare case presenting as air-space consolidation on a chest CT.

Elevated serum level of sialylated glycoprotein KL-6 predicts a poor prognosis in patients with non-small cell lung cancer treated with gefitinib

The factors affecting survival after gefitinib treatment in patients with non-small cell lung cancer (NSCLC) remain to be fully elucidated, although epidermal growth factor receptor (EGFR) mutation is a substantial prognostic factor. KL-6 has been studied as a useful indicator for interstitial lung diseases; however, it was first discovered as a lung cancer-related antigen. The aim of this study was to investigate the prognostic value of the serum KL-6 levels in advanced NSCLC patients treated with gefitinib and thus determine its association with the EGFR mutation status. Between September 2002 and September 2005, 41 patients with NSCLC were treated with gefitinib after having their serum KL-6 levels measured at Okayama University Hospital. EGFR mutations were analyzed by direct sequence methods. The serum KL-6 levels ranged from 199 to 9080U/ml (median, 550U/ml), and 54% of 41 patients showed a level higher than the cut-off level of 500U/ml. The median progression-free survival (PFS) time and the median overall survival (OS) time were 4.7 months and 13.9 months, respectively. Multivariate analyses revealed that the elevated KL-6 level was an independent adverse prognostic factor for PFS (hazard ratio: 2.278, p=0.040) as well as OS (hazard ratio: 4.858, p=0.002) in NSCLC patients treated with gefitinib. The EGFR mutation status was analyzed in 22 patients (54%). Among those with wild-type EGFR, the patients with high serum KL-6 levels also had a worse survival than those within normal serum KL-6 levels (6.5 months versus 13.3 months, p=0.0194). Our data suggest that NSCLC patients with high serum KL-6 levels tended to have a poor clinical outcome when treated with gefitinib.

Elevated serum level of sialylated glycoprotein KL-6 predicts a poor prognosis in patients with non-small cell lung cancer treated with gefitinib

18162 Background: The Factors affecting survival after gefitinib treatment in patients with non-small cell lung cancer (NSCLC) remain to be fully elucidated, although epidermal growth factor receptor (EGFR) mutation is a substantial prognostic factor. KL-6 has been studied as a useful indicator for interstitial lung diseases, however, it was first discovered as a pulmonary adenocarcinoma-related antigen. The aim of this study was to investigate the prognostic value of the serum KL-6 levels in advanced NSCLC patients treated with gefitinib and thus determine its association with the EGFR mutation status. Methods: Between September 2002 and September 2005, 41 patients with NSCLC were treated with gefitinib after having their serum KL-6 levels measured at Okayama University Hospital. EGFR mutations were analyzed by direct sequence methods. Results: The serum KL-6 levels ranged from 199 to 9080 U/ml (median, 550 U/ml), and 54% of 41 patients showed a level higher than the cut-off level of 500 U/ml. The median progression-free survival (PFS) time and the median overall survival (OS) time were 4.7 months and 13.9 months, respectively. Multivariate analyses revealed that the elevated KL-6 level was an independent adverse prognostic factor for PFS (hazard ratio: 2.278, p = 0.040) as well as OS (hazard ratio: 4.858, p = 0.002) in NSCLC patients treated with gefitinib. The EGFR mutation status was analyzed in 22 patients (54%). Among those with wild-type EGFR, the patients with high serum KL-6 levels also had a worse survival than those within normal serum KL-6 levels (6.5 months versus 13.3 months, p = 0.0194). Conclusions: Our data suggest that NSCLC patients with high serum KL-6 levels tended to have a poor clinical outcome when treated with gefitinib. No significant financial relationships to disclose.