Relevance of gamma-glutamyltransferase--a marker for apoptotic balance--in predicting tumor stage and prognosis in cervical cancer

Glutathione‑degrading enzymes in the complex landscape of tumors (Review)

Glutathione (GSH)‑degrading enzymes are essential for starting the first stages of GSH degradation. These enzymes include extracellular γ‑glutamyl transpeptidase (GGT) and intracellular GSH‑specific γ‑glutamylcyclotransferase 1 (ChaC1) and 2. These enzymes are essential for cellular activities, such as immune response, differentiation, proliferation, homeostasis regulation and programmed cell death. Tumor tissue frequently exhibits abnormal expression of GSH‑degrading enzymes, which has a key impact on the development and spread of malignancies. The present review summarizes gene and protein structure, catalytic activity and regulation of GSH‑degrading enzymes, their vital roles in tumor development (including regulation of oxidative and endoplasmic reticulum stress, control of programmed cell death, promotion of inflammation and tumorigenesis and modulation of drug resistance in tumor cells) and potential role as diagnostic biomarkers and therapeutic targets.

Association of Serum ɣ-Glutamyl Transpeptidase Levels With Overall Survival in Intermediate and Advanced Hepatocellular Carcinoma Treated With Transarterial Chemoembolization

Introduction

This article aims to evaluate the prognostic significance of pretreatment serum ɣ-glutamyl transpeptidase (GGT) levels in patients with intermediate (BCLC B) and advanced stage (BCLC C) hepatocellular carcinoma receiving transarterial chemoembolization (TACE) as first-line treatment.

Methods

In this single-center retrospective study, a total of 608 patients with BCLC B and BCLC C class were included who received TACE as first-line treatment modality. Patients were divided into low and high GGT groups based on a cutoff value of pretreatment serum GGT levels calculated by receiver operating curve. Overall survival was evaluated with Kaplan-Meier method, and intergroup significance was calculated by log-rank test for overall patients, each BCLC B and BCLC C group. Univariate and multivariate analysis were used for significance for prognostic factors.

Results

Median follow-up time was 20, 22, and 9 months for overall patients, BCLC B, and BCLC C group, respectively. Optimal cut value for GGT was calculated at 90.5 U/L. One-year and 3-year survival rates were 84.2% and 27.9% in low GGT, 49.4% and 8.6% in high-GGT group for overall patients. Multivariate analysis in overall patients showed Child-Pugh B (HR,1.801; 95%CI, 1.373-2.362, P < .001), ascites (1.393, 1.070-1.812; P = .014), multiple tumors (1.397, 1.137-1.716; P = .001), AST >40 (1.407, 1.095-1.808; P = .008), albumin <3.2 (.735, .612-.884; P = .001), AFP > 400 (1.648, 1.351-2.011; P < .001), high GGT (2.009, 1.631-2.475; P < .001), or receipt of chemo/ablation (.463, .377-.569; P < .001) as independent risk factors for overall survival. Serum GGT levels and AFP showed significant correlation in between with significance coefficient of .155 (P < .001).

Conclusion

Elevated pretreatment serum GGT level was feasible and promising independent prognostic marker for overall survival in intermediate and advanced stage hepatocellular carcinoma patients treated with TACE.

Gamma-Glutamyltransferase Activity (GGT) Is a Long-Sought Biomarker of Redox Status in Blood Circulation: A Retrospective Clinical Study of 44 Types of Human Diseases

Background and Aim. Redox equilibria are critical for life, but the biomarkers of redox status are currently unavailable. Gamma-glutamyltransferase (GGT) is an essential factor for modulating redox equilibrium through glutathione. In clinical practice, increased circulating GGT activity is used as a hepatobiliary disease biomarker. However, increased circulating GGT activities have also been observed in cancers, heart disease, diabetes, hyperuricemia, inflammation, renal insufficiency, and other diseases, explained by its role in maintaining redox equilibrium inside and outside cells. Previous studies on GGT were mainly limited to one type of disease at one time. In the current study, we systematically compared the GGT levels in 44 different human diseases to test if it could serve as a redox status biomarker in blood circulation. Methods. The clinical GGT data from 168,858 patients with 44 diseases and 132,357 healthy control in the clinical laboratory of our hospital over the past five years were retrieved. All data were analyzed with SPSS, RStudio V.1.3.1073, and python libraries 3.8. Results. Thirty-eight out of 44 diseases had significantly increased ( $p<0.001$ ) circulating GGT activities, whereas gastric cancer, anemia, renal cyst, cervical cancer, preeclampsia, and knee-joint degenerative diseases had significantly decreased ( $p<0.001$ ) GGT activities compared to the healthy control. ROC analyses showed that GGT was an excellent biomarker for liver cancer ( $\text{AUC}=0.86$ ), pancreatitis ( $\text{AUC}=0.84$ ), or hepatic encephalopathy ( $\text{AUC}=0.80$ ). All pancreas-related diseases had more than 8-fold increases in GGT activity span than the healthy control, while pancreatic cancer had a 12-fold increase (1021 U/L vs. 82 U/L). The knee-joint degenerative disease had the lowest median and narrowest GGT activity range (63 U/L). Furthermore, most diseases’ lowest to highest GGT activities were beyond the healthy control in both directions. Conclusions. Thirty-eight out of 44 diseases were in overall oxidative states defined by the increased GGT median values. In contrast, knee-joint degenerative disease, gastric cancer, anemia, renal cyst, cervical cancer, and preeclampsia were in overall antioxidative states. Moreover, most diseases swing between oxidative and antioxidative states, evidenced by the increased lowest to highest GGT activity ranges than the healthy control. Liver- and pancreas-related abnormalities were responsible for significantly increased GGT activities. Our overall results suggested that circulating GGT was a redox status biomarker.

GGT5 Is an Independent Prognostic Biomarker in Stomach Adenocarcinoma

Gastric cancer is one of the cancers with the highest incidence in the world. Gamma-glutamyltransferase 5 (GGT5) is expressed in different cancers and its role in cancers remains unclear. In this study, we aimed to evaluate the value of GGT5 in stomach adenocarcinoma (STAD). In TCGA, patients with high GGT5 expression had poor overall survival (P=0.006). Based on GSE62254, high expression of GGT5 was associated with poor OS (P=0.014) and PFS (P=0.042). The same result was observed in GSE14210. We further discovered that GGT5 expression was associated with stage, grade, and T stage. Further prognostic analysis of GGT5 showed that GGT5 was associated with prognosis in both univariate analysis (P=0.032) and multivariate analysis (P=0.029). We used gene set enrichment analysis (GSEA) to explore the possible mechanism of GGT5. GSEA suggests that overexpression of GGT5 may be involved in leukocyte transendothelial migration, JAK-STAT signaling pathway, MAPK signaling pathway, and melanoma. The high-expression GGT5 group had higher concentrations of M2 macrophages, T cell regulators, and monocytes, but the contents of plasma cells and M1 macrophages were higher in the low-expression GGT5 group. The results showed that the ESTIMATEScore, ImmuneScore, and StromalScore of the high-expression GGT5 group were higher than those of the low-expression GGT5 group. PD1 and CTLA4 expression levels were higher in the high-expression GGT5 group. The high-expression GGT5 group may be more effective for immunotherapy. These results suggested that GGT5 could be a potential prognostic molecular predictor in STAD.

A Systematic Review of Serum γ-Glutamyltransferase as a Prognostic Biomarker in Patients with Genitourinary Cancer

γ-Glutamyltransferase (GGT), a membrane-bound enzyme, contributes to the metabolism of glutathione (GSH), which plays a critical physiological role in protecting cells against oxidative stress. GGT has been proposed as a biomarker of carcinogenesis and tumor progression given that GGT activity is important during both the promotion and invasion phases in cancer cells. Moreover, GGT expression is reportedly related to drug-resistance possibly because a wide range of drugs are conjugated with GSH, the availability of which is influenced by GGT activity. While serum GGT activity is commonly used as a quick, inexpensive, yet reliable means of assessing liver function, recent epidemiological studies have shown that it may also be an indicator of an increased risk of prostate cancer development. Moreover, elevated serum GGT is reportedly an adverse prognostic predictor in patients with urologic neoplasms, including renal cell carcinoma, prostate cancer, and urothelial carcinoma, although the background mechanisms have still not been well-characterized. The present review article summarizes the possible role of GGT in cancer cells and focuses on evidence evaluation through a systematic review of the latest literature on the prognostic role of serum GGT in patients with genitourinary cancer.

The Predictive Value of Pre-therapeutic Serum Gamma-glutamyl transferase in Efficacy and Adverse Reactions to Neoadjuvant Chemotherapy among Breast Cancer Patients

Purpose

Gamma-glutamyl transferase (GGT) has been reported as being involved in tumor progression. Previous studies documented a potential relationship between serum GGT level and survival outcome in several types of human malignancies. However, the association between serum GGT levels and response to neoadjuvant chemotherapy (NAC) has not yet been reported. The present study aimed to evaluate the association between pre-therapeutic serum GGT level and the efficacy, long-term survival, and adverse reactions of NAC and to investigate its role in predicting NAC sensitivity in patients with breast cancer.

Methods

A total of 129 patients were recruited and stratified into 2 groups according to serum GGT level (< 29 U/L and ≥ 29 U/L). The association between pre-therapeutic serum GGT levels and clinicopathological parameters was examined. The correlation between pre-therapeutic serum GGT levels and pathological complete response (pCR) was analyzed using univariate and multivariate logistic regression. Survival analyses of relapse-free survival (RFS) and disease-free survival (DFS) were performed. Pearson's χ² test and multivariate logistic regression model were used to analyze the correlation between pre-therapeutic serum GGT levels and adverse reactions.

Results

Pre-therapeutic serum GGT levels were associated with pCR among breast cancer patients treated with NAC. Multivariate analysis showed that low-level GGT significantly increased pCR rate. Patients in the high-level GGT group had poorer survival than those in the low-level GGT group. Subgroup analysis demonstrated that serum GGT level was potentially related to RFS and DFS in the hormone receptor-positive group. Low levels of GGT are significantly associated with a higher incidence of neutropenia.

Conclusion

Pre-therapeutic serum GGT level is an independent and novel biomarker for predicting the efficiency, prognosis, and adverse reactions to NAC in breast cancer patients. Patients with low pre-therapeutic serum GGT levels are more likely to have higher pCR rates, better RFS and DFS, and higher hematologic toxicity.

Trial Registration

ClinicalTrials.gov Identifier: NCT02199418, NCT02221999

Cell-Membrane-Localizing, Two-Photon Probe for Ratiometric Imaging of γ-Glutamyl Transpeptidase in Cancerous Cells and Tissues

γ-Glutamyl transpeptidase (GGT), a cell surface-bound protease, is associated with various diseases including cancer. The detection of the enzyme activity is an important subject, leading to about 40 activatable fluorescent probes so far. All of them, however, lack the membrane-localizing ability, raising a reliability issue in the quantitative analysis. Disclosed is the first fluorescent probe that senses the cell surface-bound enzyme, which, furthermore, is capable of ratiometric as well as two-photon imaging with desirable features. Ratiometric imaging of cancer cell lines reveals a 6.4-8.4-fold higher GGT levels than those in normal cell lines. A comparison of the enzyme activity in organ tissues of normal and tumor xenograft mice reveals notably different levels of enzyme activity depending on the kind of tissue. Normal tissues exhibited comparable levels of enzyme activity, except the kidney that has significantly higher GGT activity (2.7-4.0-fold) than the other organs. Compared with the normal tissues, considerably higher enzyme activity was observed in the tumor tissues of the thigh (4.0-fold), colon (2.5-fold), lung (3.6-fold), and liver (2.1-fold), but essentially no enhanced activity in the tumor tissues of the spleen, stomach, and pancreas and a comparable level in both the tumor and normal kidney tissues were observed. The probe offers practical means for studying GGT-associated biology in cells and tissues by one- as well as two-photon ratiometric imaging.

Novel Value of Preoperative Gamma-Glutamyltransferase Levels in the Prognosis of AFP-Negative Hepatocellular Carcinoma

Background

Gamma-glutamyltransferase (GGT) is involved in tumor development and progression, but its prognostic value in α-fetoprotein- (AFP-) negative (AFP < 25 ng/mL) hepatocellular carcinoma (HCC) patients remains unknown.

Methods

A large cohort of 678 patients with AFP-negative HCC following curative resection who had complete data were enrolled in this study. The optimal cutoff value for the preoperative level of GGT was determined by the X-tile program. Independent prognostic factors for overall survival (OS) and disease-free survival (DFS) were also identified.

Results

The optimal cutoff values for the preoperative levels of GGT were 37.2 U/L and 102.8 U/L, which were used to divide all patients into three subgroups (group 1, GGT < 37.2 U/L (n = 211, 31.1%); group 2, GGT ≥ 37.2 and <102.8 U/L (n = 320, 47.2%); group 3, GGT ≥ 102.8 U/L (n = 147, 21.7%)), with distinct OS times (58.5 vs. 53.5 vs. 44.4 months, P < 0.001) and DFS times (47.9 vs. 40.3 vs. 30.1 months, P < 0.001). Elevated preoperative GGT levels were associated with an unfavorable tumor burden (larger tumor size, multiple tumors, and microvascular invasion) and were selected as independent predictors of a worse OS (group 2 vs. group 1, HR: 1.73 (1.13-2.65), P = 0.011; group 3 vs. group 1, HR: 3.28 (2.10-5.13), P < 0.001) and DFS (group 2 vs. group 1, HR: 1.52 (1.13-2.05), P = 0.006; group 3 vs. group 1, HR: 2.11 (1.49-2.98), P < 0.001) in multivariable analysis.

Conclusions

Elevated preoperative GGT levels are associated with an unfavorable tumor burden and serve as an independent prognostic marker for worse outcomes in AFP-negative HCC patients following resection.

Cancer-associated fibroblasts-derived gamma-glutamyltransferase 5 promotes tumor growth and drug resistance in lung adenocarcinoma

Gamma-glutamyltransferase 5 (GGT5) is a member of the gamma-glutamyl transpeptidase gene family with the capacity of cleaving the gamma-glutamyl moiety of glutathione, but its role in cancer progression has never been revealed. In this study, we found that gene GGT5 was highly expressed in cancer-associated fibroblasts (CAFs) in lung adenocarcinoma, predicting the unfavorable survival of patients with lung adenocarcinoma. Cell growth, foci formation and spheres formation analyses showed that cancer cell proliferation was attenuated under treatment with the conditioned media from GGT5-silenced CAFs. Moreover, high expression of GGT5 in CAFs enhanced the drug resistance of cancer cells by increasing intracellular glutathione and reducing the intracellular reactive oxygen species in cancer cells. In mouse xenograft model, we proved that targeting GGT5 with a small-molecule inhibitor GGsTop could inhibit tumor growth and increase the chemosensitivity of cancer cells. Taken together, our study illuminates that high level of GGT5 in CAFs contributes to cancer cell survival and drug resistance, indicating that GGT5 may be a promising therapeutic target in lung adenocarcinoma.

Serum gamma-glutamyltransferase and the overall survival of metastatic pancreatic cancer

Background

Accumulating evidence suggests that Gamma-glutamyltransferase (GGT) may be involved in cancer occurrence and progression. However, the prognostic role of serum GGT in pancreatic cancer (PC) survival lacks adequate evaluation. In this study, we aimed to analyze the association between serum GGT measured at diagnosis and overall survival (OS) in patients with metastatic PC.

Methods

We identified 320 patients with histopathologically confirmed metastatic pancreatic ductal adenocarcinoma (PDAC) diagnosed during 2015 and 2016 at a specialized cancer hospital in southwestern China. Univariate and multivariate Cox proportional-hazards models were used to determine associations between serum GGT and OS in metastatic PDAC.

Results

Controlled for possible confounding factors, serum GGT was significantly associated with OS: serum GGT > 48 U/L yielded a hazard ratio of 1.53 (95% CI: 1.19–1.97) for mortality risk. A significant dose-response association between serum GGT and OS was also observed. Subgroup analysis showed a possible interaction between GGT and blood glucose level.

Conclusion

Serum GGT could be a potential indicator of survival in metastatic PDAC patients. Underlying mechanisms for this association should be investigated.

Gamma-glutamyltransferase as a preoperative differential diagnostic marker in patients with adnexal mass

OBJECTIVE

Gamma-glutamyltransferase (GGT) is involved in tumor development, progression and chemotherapy resistance. The present study evaluated GGT serum levels as a preoperative predictive marker for ovarian cancer in patients with adnexal mass.

STUDY DESIGN

Preoperative GGT serum levels of 2235 patients with adnexal mass and subsequent surgery were ascertained (patients with benign ovarian tumors: n = 1811; borderline tumor of the ovary [BTO]: n = 85; epithelial ovarian cancer [EOC]: n = 339). Standardized expert transvaginal ultrasound was documented.

RESULTS

Median (interquartile range) GGT serum levels in patients with benign ovarian tumors, BTO, and EOC were 15.0 U/l (11.0-23.0), 17.0 U/l (10.0-23.5), and 20.0 U/l (13.0-34.0), respectively (p = 0.002). Elevated GGT serum levels were associated with the presence of BTO/EOC in univariate analysis (p < 0.0001, hazard ratio 1.8, confidence interval 1.5-2.3). GGT did not outperform established tools for preoperative prediction of BTO/EOC in patients with adnexal mass, such as CA-125 measurement or transvaginal ultrasound.

CONCLUSION

Elevated GGT serum levels were not associated with the presence of BTO/EOC in women with suspicious adnexal mass in multivariate analysis. GGT serum levels did not outperform established risk factors and therefore might add only limited additional value to CA-125 serum levels in the differential diagnosis between benign and malignant adnexal masses.

Prognostic significance of gamma-glutamyl transferase in patients with metastatic non-small cell lung cancer

BACKGROUND

The prognostic significance of serum gamma-glutamyl transferase (GGT) level at diagnosis in patients with metastatic non-small lung cancer (NSCLC) is not clear. We aimed to assess the relationship between serum GGT level and overall survival (OS) and progression-free survival (PFS) in this patient population.

METHODS

Data of patients with metastatic NSCLC who were admitted to the medical oncology clinic of our hospital during April 2013-December 2017 were retrospectively analyzed. Patients were divided into two groups based on GGT levels, normal and high (as defined by normal reference levels), and then compared.

RESULTS

Significant differences between the high and normal GGT level groups were found regarding female sex, Eastern Cooperative Oncology Group performance score, weight loss at the time of diagnosis, and lactate dehydrogenase level (p < 0.05). The high GGT group had a shorter median OS (11.5 vs. 3.4 months, p < 0.001) and PFS (7.8 vs. 3.0 months, p = 0.001). High GGT level is an independent risk factor for OS (hazard ratio [HR] 2.270; 95% confidence interval [CI], 1.398-3.686; p < 0.001) and PFS (HR 2.489; 95% CI, 1.323-4.684; p = 0.005).

CONCLUSIONS

High serum GGT level is an independent prognostic factor for OS and PFS in metastatic NSCLC patients.

Prognostic significance of serum γ-glutamyltransferase in patients with advanced urothelial carcinoma

OBJECTIVES

Serum γ-glutamyltransferase (GGT) is reportedly associated with prognosis in patients with various malignancies. However, the prognostic role of GGT is unknown among patients with advanced urothelial carcinoma (aUC). This study was designed to examine the prognostic role of serum GGT in patients with aUC.

MATERIALS AND METHODS

Charts of 125 consecutive aUC patients (inoperable cT4 and/or metastasis to lymph nodes/distant organs) managed at a single cancer center between 2004 and 2016 were retrospectively reviewed. Variables collected included age, sex, body mass index, Karnofsky performance status, primary site, clinical tumor stage, lymph node/visceral metastasis, hepatic comorbidities, the presence of curative treatment before the diagnosis of aUC, white blood cell count, neutrophil-to-lymphocyte ratio, hemoglobin, albumin, lactate dehydrogenase, alkaline phosphatase, GGT, C-reactive protein, and treatments given after the diagnosis of aUC. Associations of variables with overall survival (OS) were analyzed using the Cox proportional hazard model.

RESULTS

Serum GGT was elevated (≥60 U/l) at the diagnosis of aUC in 16 patients (13%). During follow-up period (median 12.1 months), 101 patients died (2-year OS rate, 32%). Patients with elevated GGT at the diagnosis of aUC had a significantly poorer prognosis than those with normal GGT with respective 2-year OS rates of 0% and 37% (P < 0.001). On multivariate analysis, elevated GGT was a significant and independent risk factor for shorter OS (hazard ratio, HR = 2.97; P < 0.001) as were poorer Karnofsky performance status (HR = 3.47; P < 0.001), elevated lactate dehydrogenase (HR = 1.86; P = 0.033), advanced age (HR = 1.82; P = 0.013), elevated neutrophil-to-lymphocyte ratio (HR = 1.80; P = 0.015), elevated C-reactive protein (HR = 1.73; P = 0.018), the absence of systemic chemotherapy (HR = 1.71; P = 0.035), and primary site of upper urinary tract (HR = 1.71; P = 0.014) in descending order by HR. The prognostic significance of elevated GGT was also observed in a subset of 101 patients who had been diagnosed with aUC at their first presentation.

CONCLUSION

The present study for the first time demonstrated that elevated serum GGT was an independent adverse prognostic factor in aUC patients.

Prognostic value of serum liver enzymes in oral and oropharynx squamous cell carcinomas

BACKGROUND

Serum liver enzymes, which catalyze relevant catabolic pathways, have been indicated to be diagnostic and prognostic tools for several malignant tumors. The correlation between serum liver enzymes levels and survival in patients with oral and oropharynx squamous cell carcinomas (OSCC) is still absent. Here, we conducted a study focusing on predictive value of serum liver enzymes in terms of prognosis in the patients.

METHODS

A retrospective study including 134 OSCC patients from years 2009 to 2014 was performed to investigate the association between levels of pre-treatment serum liver enzymes, various clinical parameters and prognostic outcomes, which are overall survival (OS) and disease-free survival (DFS). Log-rank tests with Kaplan-Meier method were used to detect potential prognostic biomarkers. Multivariate analyses by Cox proportional hazards model were used to identify significant predictors of prognosis.

RESULTS

Serum adenosine deaminase (ADA) level was associated with patients' OS and DFS by univariate analyses (P = 0.006 and P = 0.024, respectively). Multivariate analyses showed that higher serum ADA (>17.2 U/L) (P = 0.019) as well as positive lymph node status (P = 0.035) independently predicted worse OS of patients with OSCC. In addition, older age (≥60 years) (P = 0.043) and positive lymph node status (P = 0.027) were independently prognostic parameters for poorer DFS.

CONCLUSIONS

Pre-operative serum ADA levels may serve as a reliable independent prognostic predictor for OS in OSCC patients.

Prognostic significance of the pretreatment serum gamma-glutamyltransferase levels in Chinese patients with non-metastatic cervical cancer

This study was performed to evaluate the prognostic significance of the pretreatment serum gamma-glutamyltransferase (GGT) levels in a Chinese cohort of patients with early-stage or locally advanced cervical cancer. The pretreatment serum GGT levels were examined in 290 cervical cancer patients with stage I-III disease and 230 healthy controls selected from a cancer-free population in the same region. Patients were assigned to normal or high-risk GGT groups, as previously described, and the GGT levels were correlated to clinicopathologic parameters and survival data. The GGT levels in cervical cancer patients were significantly higher than those in healthy controls (35.6 ± 29.1 vs. 24.1 ± 14.7 U/L, P < 0.001). In addition, the pretreatment serum GGT levels were associated with the histology type (P = 0.023), lymph node involvement (P = 0.040), stage (P = 0.029), recurrence (P = 0.015) and death (P = 0.005), but not with age (P = 0.432), tumor size (P = 0.067) or degree of differentiation (P = 0.901). Moreover, univariate survival analysis revealed that patients with high GGT levels tended to have poorer disease-free survival (DFS) [hazard ratio (HR), 1.721; 95% confidence interval (CI), 1.189–2.491; P = 0.004] and overall survival (OS) (HR, 1.929; 95% CI, 1.294–2.876; P = 0.001) compared to those with normal GGT levels. However, a multivariate Cox-regression model did not support these data (HR, 1.373; 95% CI, 0.925–2.039; P = 0.116 for DFS and HR, 1.357; 95% CI, 0.887–2.078; P = 0.160 for OS, respectively) after adjusting for other confounding variables. High pretreatment serum GGT was associated with more advanced tumor behavior, but could not serve as an independent prognostic indicator in patients with early-stage or locally advanced cervical cancer.

Albumin to gamma-glutamyltransferase ratio as a prognostic indicator in intrahepatic cholangiocarcinoma after curative resection

The prognosis of intrahepatic cholangiocarcinoma (ICC) remains poor whereas predictive models for survival prediction in ICC patients following curative resection are limited. Herein, we established a novel inflammation-based score derived from preoperative albumin to gamma-glutamyltransferase ratio (AGR) and evaluated its prognostic significance in ICC patients underwent curative resection. Prognostic value of AGR was retrospectively studied in a cohort comprising 206 ICC patients following curative resection. The predictive performance of AGR was compared with other inflammation-based scores and serological tumor markers in terms of concordance index (C-index). Further, prognostic nomograms incorporating AGR into the tumor-node-metastasis (TNM) staging systems were established to achieve a better discriminatory ability. The optimal cut-off value of AGR was 0.6. Multivariate analysis showed that AGR was an independent predictor for overall survival (OS; P = 0.003) and recurrence-free survival (RFS; P = 0.046). The C-index of AGR was superior to other inflammation-based scores and serological tumor markers in OS and RFS prediction. The established nomograms showed improved predictive accuracy compared with the TNM staging systems alone. These results indicate that AGR is an independent prognostic indicator for ICC underwent curative resection. The incorporation of AGR into the existing TNM staging systems achieved improved predictive accuracy.

High pretreatment serum gamma-glutamyl transpeptidase predicts an inferior outcome in nasopharyngeal carcinoma

Background

Gamma-glutamyl transpeptidase (GGT) which plays an important role in tumor initiation, invasion, drug resistance is strongly associated with poor prognosis in patients with cancers. This study was designed to estimate whether pretreatment serum GGT could predict the clinical outcome of nasopharyngeal carcinoma (NPC) patients.

Results

An optimal cutoff value was identified as 23 U/L for GGT. Univariate analysis and multivariate analysis demonstrated that elevated GGT was correlated with shorter local recurrence-free survival (LRFS) (HR, 4.163; 95% CI, 1.690-10.251; p=0.023), progression-free survival (PFS) (HR, 3.119; 95% CI, 1.955-4.976; p=0.031) and overall survival (OS) (HR, 2.811; 95% CI, 1.614-4.896; p=0.007).

Materials and Methods

We retrospectively analyzed data from 374 patients with NPC. Kaplan–Meier method was used to calculate and compare the prognosis. The Cox proportional hazards model was applied to carry out univariate and multivariate analyses.

Conclusion

Pretreatment GGT can be a novel and independent prognostic biomarker for patients with NPC.

Prognostic impact of pretherapeutic gamma-glutamyltransferase on patients with nasopharyngeal carcinoma

Background

Gamma-glutamyltransferase (GGT) is a membrane-bound enzyme involved in the metabolism of glutathione. Studies suggested that GGT played an important role in the tumor development, progression, invasion and drug resistance and prognosis. The association between GGT and prognosis of patients with nasopharyngeal carcinoma (NPC) was unknown. This study was conducted to investigate the association of pretherapeutic serum level of GGT with clinical-pathological parameters and survival in patients with NPC.

Methods

Two hundred and twenty-two patients with NPC were recruited in this study and were stratified into two GGT risk groups (≤ 34.5 U/L, > 34.5 U/L). The association of pretherapeutic serum GGT levels with clinical–pathological parameters was examined. Univariate and multivariate survival analyses were performed.

Findings

The pretherapeutic serum level of GGT was not associated with gender, age, pathology, T stage, N stage, TNM stage, chemotherapy or radiotherapy in patients with NPC. Patients in the high-risk GGT group had a poorer survival than the low-risk GGT group (3-year overall survival, 74.2% vs. 50.2%, P = 0.001; 3-year progression-free survival, 76.4% vs. 47.1%, P < 0.001; 3-year loco-regional relapse-free survival, 76.4% vs. 51.3%, P < 0.001; 3-year distant metastasis-free survival, 89.5% vs. 66.4%, P < 0.001). Multivariate analysis suggested that patients in the high-risk GGT group had 2.117 (95% confidence interval [CI], 1.225 ∼ 3.659, P = 0.007) times the risk of death, 2.836 (95% CI, 1.765 ∼ 4.557, P < 0.001) times the risk of progression, 2.551 (95% CI, 1.573 ∼ 4.138, P < 0.001) times the risk of relapse, and 3.331 (95% CI, 1.676 ∼ 6.622, P < 0.001) times the risk of metastasis compared with those in the low-risk GGT group.

Conclusion

The pretherapeutic serum level of GGT might serve as a novel independent prognostic factor for overall-survival, progression-free survival, loco-regional relapse-free survival and distant metastasis-free survival in patients with NPC.

Gamma-glutamyltransferase as novel biomarker in patients with uterine leiomyosarcoma

Gamma-glutamyltransferase (GGT) is an established marker for proliferative/apoptotic balance and has been associated with cancer risk and prognosis. The aim of this study was to evaluate the value of pre-treatment GGT serum levels as prognostic biomarker in patients with primary uterine leiomyosarcoma (ULMS). Data of women with ULMS were extracted from a multi-center database. Pre-treatment GGT serum levels were measured and patients assigned to predefined GGT risk groups. GGT values were correlated with clinico-pathological parameters and univariate and multivariable survival analyses were performed. A total of 44 patients with ULMS were analyzed. Mean (SD) pre-therapeutic GGT serum level was 33.8 (39.8) U/L. In Figo Stage I versus II-IV mean (SD) GGT values were 28.8 (34.0) U/l and 43.5 (49.2) U/l, respectively (p = 0.25). Five-year overall survival (OS) rates in ULMS patients with normal low versus higher GGT levels were 70% and 37%, respectively (p = 0.043). Univariate and multivariable analyses revealed that higher GGT serum levels (p = 0.043, p = 0.005) and high histological grade (p = 0.029, p = 0.012) were independently associated with impaired OS, respectively. Higher pre-treatment GGT serum levels were independently associated with unfavorable prognosis in women with ULMS. Thus, GGT seems to be a useful novel biomarker in ULMS.

Prognostic significance of gamma-glutamyltransferase in patients with resectable esophageal squamous cell carcinoma

Gamma-glutamyltransferase (GGT) is a membrane-bound enzyme involved in the glutathione metabolism. Studies suggested that GGT was a marker of apoptotic balance and modulated tumor progression, invasion and drug resistance. Recently, GGT was shown to be associated with the progression of high-grade esophageal epithelial dysplasia to invasive carcinoma. This study was conducted to investigate the value of pre-therapeutic serum GGT levels as prognostic parameter in esophageal squamous cell carcinoma. Six hundred thirty-nine resectable esophageal squamous cell carcinoma patients were recruited in this study and were stratified into two GGT risk groups. The association of pre-therapeutic serum GGT levels and clinical-pathological parameters was examined. Univariate and multivariate survival analyses were performed. GGT serum levels were associated with gender, smoking status, TNM stage and lymph node involvement. Higher pre-therapeutic serum GGT was found in males, smoker, advanced TNM stage and lymph node positive patients. Patients assigned to the low-risk group had higher 5-year overall survival rate (53.1% vs. 33.0%, P < 0.01) and disease-free survival rate (45.2% vs. 23.4%, P < 0.01) than the high-risk group. Patients with high-risk group of GGT had 1.568 (95% confidence interval [CI], 1.259 ∼ 1.952) times the risk of death and 1.582 (95% CI, 1.286 ∼ 1.946) times the risk of disease recurrence contrast with those with low-risk group of GGT. The pre-therapeutic serum GGT is a novel independent prognostic parameter for disease-free survival and overall survival in resectable esophageal squamous cell carcinoma.

Prognostic relevance of pretherapeutic gamma-glutamyltransferase in patients with primary metastatic breast cancer

Background

Gamma-glutamyltransferase (GGT) is a known marker for apoptotic balance and cell detoxification. Recently, an association of baseline GGT levels and breast cancer incidence, tumor progression and chemotherapy resistance was shown. The purpose of this study was to evaluate the association of pre-therapeutic GGT levels, clinical-pathological parameters and survival in patients with primary metastatic breast cancer (PMBC).

Methods

In this multicenter analysis, pre-therapeutic GGT levels and clinical-pathological parameters of 114 patients diagnosed with PMBC between 1996 and 2012 were evaluated. The association between GGT levels and clinical-pathological parameters were analysed. Patients were stratified into four GGT risk-groups (GGT < 18.00 U/L: normal low, 18.00 to 35.99 U/L: normal high, 36.00 to 71.99 U/L: elevated and ≥ 72.00 U/L: highly elevated) and survival analyses were performed.

Findings

Patients in the high risk GGT group had a poorer overall survival, when compared to the low risk group with five-year overall survival rates of 39.5% and 53.7% (p = 0.04), respectively. Patients with larger breast tumors had a trend towards higher GGT levels (p = 0.053). Pre-therapeutic GGT levels were not associated with indicators of aggressive tumor biology such as HER2-status, triple negative histology, or poorly differentiated cancers.

Conclusion

Pre-therapeutic GGT serum level might serve as a novel prognostic factor for overall-survival in patients with PMBC.

Preoperative serum-gamma-glutamyltransferase (GGT) does not represent an independent prognostic factor in a European cohort of patients with non-metastatic renal cell carcinoma

AIMS

Increasing evidence suggests that the serum-gamma-glutamyltransferase (GGT) might correlate with tumour development and growth rates in various human cancer types. Thus, we decided to investigate the potential prognostic impact of the preoperatively assessed serum-GGT in a European cohort of patients with non-metastatic renal cell carcinoma (RCC).

METHODS

Clinicopathological data from 700 consecutive patients with non-metastatic RCC, operated between 2000 and 2010 at a single tertiary academic centre, were evaluated retrospectively. Preoperative serum-GGT was assessed 1 day before surgery. Patients were categorised using a serum-GGT cut-off value of 40 U/L according to a calculation by receiver operating curve analysis. Patients' cancer-specific survival (CSS), metastasis-free survival (MFS), as well as overall survival (OS) were assessed using the Kaplan-Meier method and Cox proportional models.

RESULTS

In univariate analysis, an elevated preoperative serum-GGT level (<40 U/L vs ≥40 U/L) was statistically significantly associated with a shorter MFS (HR=1.517, 95% CI 1.047 to 2.197, p=0.027). In multivariate analyses, pathological T-Stage (pT-1 vs pT-2-4, HR=2.065, 95% CI 1.665 to 2.560), tumour grade (G-1+G-2 vs G-3+G-4, HR=1.671, 95% CI 1.261 to 2.213), as well as the presence of histological tumour necrosis (No vs Yes, HR=2.031, 95% CI 1.355 to 3.046) were independent predictors of MFS in patients with RCC, whereas the preoperative serum-GGT failed to reach independent predictor status (<40 U/L vs ≥40 U/L, HR=1.156, 95% CI 0.791 to 1.690). No prognostic role for GGT in OS or CSS could be identified.

CONCLUSIONS

In the cohort studied, patients with an elevated (≥40 U/L) preoperative serum-GGT had a subsequently shorter MFS only in univariate analysis. In contrast to previous studies, our data failed to demonstrate preoperatively assessed serum-GGT as an independent prognostic factor in patients with non-metastatic RCC.

Pretherapeutic gamma-glutamyltransferase is an independent prognostic factor for patients with renal cell carcinoma

BACKGROUND

Gamma-glutamyltransferase (GGT) regulates apoptotic balance and promotes cancer progression and invasion. Higher pretherapeutic GGT serum levels have been associated with worse outcomes in various malignancies, but there are no data for renal cell carcinoma (RCC).

METHODS

Pretherapeutic GGT serum levels and clinicopathological parameters were retrospectively evaluated in 921 consecutive RCC patients treated with nephrectomy at a single institution between 1998 and 2013. Gamma-glutamyltransferase was analysed as continuous and categorical variable. Associations with RCC-specific survival were assessed with Cox proportional hazards models. Discrimination was measured with the C-index. Decision-curve analysis was used to evaluate the clinical net benefit. The median postoperative follow-up was 45 months.

RESULTS

Median pretherapeutic serum GGT level was 25 U l(-1). Gamma-glutamyltransferase levels increased with advancing T (P<0.001), N (P=0.006) and M stages (P<0.001), higher grades (P<0.001), and presence of tumour necrosis (P<0.001). An increase of GGT by 10 U l(-1) was associated with an increase in the risk of death from RCC by 4% (HR 1.04, P<0.001). Based on recursive partitioning-based survival tree analysis, we defined four prognostic categories of GGT: normal low (<17.5 U l(-1)), normal high (17.5 to <34.5 U l(-1)), elevated (34.5 to <181.5 U l(-1)), and highly elevated (⩾181.5 U l(-1)). In multivariable analyses that adjusted for the effect of standard features, both continuously and categorically coded GGT were independent prognostic factors. Adding GGT to a model that included standard features increased the discrimination by 0.9% to 1.8% and improved the clinical net benefit.

CONCLUSIONS

Pretherapeutic serum GGT is a novel and independent prognostic factor for patients with RCC. Stratifying patients into prognostic subgroups according to GGT may be used for patient counselling, tailoring surveillance, individualised treatment planning, and clinical trial design.

Association of gamma-glutamyltransferase with severity of disease at diagnosis and prognosis of ovarian cancer

Background:

Gamma-glutamyltransferase (GGT) – a membrane-bound enzyme crucially involved in the cell's detoxification pathway and apoptotic balance – is involved in tumour development, progression and chemotherapy resistance. Elevated GGT serum levels are associated with increased cancer risk in women and worse prognosis in gynaecologic cancers. The present study investigated the prognostic role of GGT in ovarian cancer patients.

Methods:

In this multicenter study, pre-therapeutic GGT levels were ascertained in 634 consecutive patients with epithelial ovarian cancer (EOC, n=567) and borderline tumour of the ovary (BTO, n=67). Gamma-glutamyltransferase serum levels were associated with clinicopathological parameters and uni- and multivariate survival analyses were performed. Immunohistochemistry of GGT was performed in ovarian cancer tissue and correlated with GGT serum levels.

Results:

Pre-therapeutic GGT serum levels were higher in patients with EOC (28.56 (38.24) U l⁻¹) than in patients with BTO (20.01 (12.78) U l⁻¹, P=0.01). High GGT serum levels were associated with advanced FIGO stage (P<0.001) and with worse overall survival in univariate (P<0.001) and multivariable analysis (P=0.02, HR 1.2 (1.1–1.5)). We further investigated the association between systemic GGT serum levels and local GGT expression in EOC tumour tissue and observed an association between these two parameters (P=0.03).

Conclusion:

High pre-therapeutic GGT serum levels are associated with advanced tumour stage and serve as an independent prognostic marker for worse overall survival in patients with EOC. Gamma-glutamyltransferase expression in ovarian cancer tissue is reflected in GGT serum levels.

Prognostic significance of gamma-glutamyltransferase in patients with endometrial cancer: a multi-centre trial

Background:

Gamma-glutamyltransferase (GTT), a known marker for apoptotic balance, seems to promote tumour progression, invasion and drug resistance. Recently, high GGT serum levels were shown to be associated with impaired prognosis in patients with cervical cancer. The aim of this study was to investigate the value of pre-therapeutic serum GGT levels as prognostic parameter in patients with endometrial cancer.

Methods:

Within the present multi-centre trial, clinical–pathological parameters and pre-therapeutic serum GGT levels were evaluated in 874 consecutive patients with endometrial cancer. Patients were stratified in GGT risk groups, and univariate and multivariable survival analyses were performed.

Results:

Mean pre-therapeutic serum GGT level was 30.8 (41.5) U l^–1. Elevated and highly elevated serum GGT levels (P=0.03 and P=0.005), tumour stage (P<0.001 and P<0.001), grade (P<0.001 and P=0.02) and age (P<0.001 and P<0.001) were independently associated with progression-free survival in univariate and multivariable survival analyses. Pre-therapeutic GGT was not associated with advanced tumour stage (P=0.6), higher histological grade (P=0.6) or unfavourable histological subtype (P=0.3).

Conclusion:

Pre-therapeutic serum GGT is a novel and independent prognostic parameter for progression-free survival of patients with endometrial cancer. Stratifying patients into prognostic subgroups could be used for patient counselling and individualised treatment planning.