Human kallikrein gene 11 (KLK11) mRNA overexpression is associated with poor prognosis in patients with epithelial ovarian cancer.

PURPOSE: The purpose of this study was to examine expression levels of the human tissue kallikrein 11 gene (KLK11) in epithelial ovarian tumors and to identify the relationship between KLK11 expression and patient survival. EXPERIMENTAL DESIGN: KLK11 mRNA expression was examined by semiquantitative PCR in 64 epithelial ovarian tumors (7 adenomas, 6 low malignant potential tumors, and 51 adenocarcinomas) and in 10 normal ovaries. Semiquantitative PCR results were correlated with clinicopathologic variables and overall survival. cDNA from human normal tissues and tumor tissues was also analyzed. RESULTS: KLK11 mRNA expression was detected in various human cancer tissues including breast, lung, colon, prostate, pancreas, and ovarian carcinoma. The mean value of relative KLK11 expression ratio was significantly higher in ovarian tumor samples than in normal ovary samples (compared with normal samples: adenoma, P = 0.0006; low malignant potential tumor, P = 0.0049; and carcinoma, P < 0.0001). No statistically significant associations between KLK11 mRNA expression level and clinical stage, histological type, or histological grade were observed. The log-rank test showed that high KLK11 mRNA expression and advanced clinical stage significantly correlated with poor patient survival (P = 0.0185 and P = 0.0043, respectively). High KLK11 mRNA expression and clinical stage remained significantly associated with overall survival (P = 0.0225 and P = 0.0202, respectively) after multivariate analysis. CONCLUSIONS: KLK11 expression may play an important role in ovarian cancer development and act as an independent prognostic marker in ovarian cancer patients.     

人类组织激肽释放酶6在卵巢上皮性癌中的表达及临床意义

[目的]研究人类组织激肽释放酶（kallikrein,KLK）6蛋白在卵巢上皮性癌组织及腹膜后淋巴结中的表达,探讨其在卵巢上皮性癌中的临床意义。[方法]回顾性分析卵巢肿瘤患者的临床病理资料,采用免疫组化检测72例卵巢癌、16例卵巢交界性肿瘤、20例良性卵巢上皮性肿瘤组织KLK6蛋白的表达;并采用配对设计研究KLK6蛋白在卵巢癌患者腹膜后淋巴结中的表达．探讨KLK6在卵巢上皮性癌发生、发展中的作用。[结果]KLK6在卵巢癌及交界性卵巢肿瘤中的阳性表达分别为52．8％（38／72）、25．O％（4／16）,均显著强于良性上皮性卵巢肿瘤15．0％（3／20）f19〈0．05）。KLK6阳性表达与卵巢癌的临床分期、组织学分级及淋巴结转移有关fP〈0．05）,与组织学类型无相关性（P〉0．05）;KLK6在卵巢癌原发灶与腹膜后转移淋巴结组织中的表达呈正相关（r=8．91,P=0．003）;KLK6阳性与阴性患者的平均生存时间分别为25．9个月和49．2个月（P〈O．051。[结论]KLK6高表达可能在卵巢上皮性癌的发生发展中起潜在作用,KLK6可能与卵巢上皮性癌的浸润、转移有关,KLK6是卵巢癌的不良预后因素之一。     

Human kallikrein 8 (hK8/TADG-14) expression is associated with an early clinical stage and favorable prognosis in ovarian cancer

The purpose of this study was to examine human kallikrein 8 (hK8/TADG-14) expression in epithelial ovarian tumors and to investigate the association of hK8 expression levels with patient survival. Human kallikrein 8 protein (hK8) expression was examined by immunohistochemistry in 74 ovarian adenocarcinomas and 6 normal ovaries. Results of immunostaining were correlated with clinicopathological variables and overall survival of the patients. Human kallikrein 8 gene (KLK8) mRNA expression was examined by semi-quantitative PCR in 35 ovarian tumors and 7 normal ovaries. Expression of hK8 was not detected on the surface epithelium of normal ovaries. In contrast, hK8 expression was detected in 51.4% (38/74) of carcinomas with a significantly higher detection rate of hK8 expression being observed in early stage disease compared to advanced stage disease (p=0.0192). Data analysis using the log-rank test showed hK8 expression correlated significantly with favorable patient survival (p=0.0328). Younger age (p=0.0008), early clinical stage (p<0.0001), and low histological grades of the tumors (p=0.0018) were also associated significantly with a favorable prognosis. In a multivariate model, age (p=0.0186) and clinical stage (p<0.0001) remained associated significantly with overall survival, whereas hK8 expression and histological grade lost their significance. There was significant relationship between the hK8 expression status and KLK8 mRNA expression levels (p=0.0304). Expression of hK8 is increased during the development of ovarian cancer and down-regulated during ovarian cancer progression. Expression of hK8 is a favorable prognostic marker in patients with ovarian cancer.     

Kallikrein-related peptidase 4 (KLK4) mRNA predicts short-term relapse in colorectal adenocarcinoma patients

The members of the kallikrein-related peptidase (KLK) family are aberrantly expressed in cancer, including colorectal adenocarcinoma. KLK4 is an endogenous activator of protease-activated receptor 1 (PAR1) in HT-29 colorectal adenocarcinoma cells, inducing PAR1 signaling and subsequent ERK1/2 activation. The aim of this study was to analyze KLK4 mRNA expression in colorectal adenocarcinoma and to examine its prognostic value as a novel molecular tissue biomarker in this malignancy. Therefore, total RNA was isolated from primary tumors of 81 colorectal adenocarcinoma patients, cDNA was prepared, and KLK4 mRNA expression analysis was performed using quantitative real-time PCR. KLK4 mRNA was significantly associated with the Dukes stage, tumor invasion, size, and histological grade. Survival analysis demonstrated that KLK4 mRNA expression constitutes an unfavorable prognostic biomarker in colorectal adenocarcinoma, predicting poor disease-free survival (DFS), independently of the nodal status and tumor size. Furthermore, KLK4 mRNA predicts short-term relapse of lymph node-negative patients or those with tumors of early Dukes stage. In conclusion, KLK4 mRNA expression can be regarded as a novel potential tissue biomarker in colorectal adenocarcinoma.     

Characterization of KLK4 expression and detection of KLK4-specific antibody in prostate cancer patient sera

The ability to identify prostate tumor or prostate tissue specific genes that are expressed at high levels and use their protein products as targets could greatly aid in the diagnosis and treatment of prostate cancer. Using a polymerase chain reaction (PCR)-based subtraction technique, we have recovered the recently described KLK4 (prostase) gene from human prostate cDNA. In this study, KLK4 gene expression in human prostate tumors was further characterized using cDNA quantitative PCR and immunohistochemistry, demonstrating that the gene is specifically expressed at both the mRNA and protein levels in normal human prostate tissue, and in both primary and metastatic prostate tumor samples. Quantitative mRNA analysis also demonstrated low level expression including adrenal gland, salivary gland and thyroid. Finally, it was demonstrated that prostate cancer patient sera contain antibodies that bind specifically to recombinant KLK4 protein. This antibody has been used to detect KLK4-specific peptides in epitope mapping experiments. The relatively specific expression profile and elevated level of KLK4 mRNA and protein in both tumor and normal prostate tissues, in addition to detectable KLK4-specific antibody in cancer patient sera, supports additional efforts to determine if KLK4 can play a role in the diagnosis of prostate cancer, the monitoring of residual disease, or act as a target for immunotherapy.     

Kallikrein-related peptidase 6 (KLK6)gene expression in intracranial tumors

Kallikrein-related peptidases (KLKs) are emerging novel new biomarkers for prognosis, diagnosis and therapeutic intervention of cancer. Kallikrein-related peptidase 6 (KLK6) has the highest expression in normal brain among other tissues. Although its expression has been extensively studied in many types of cancer and in neurodegenerative diseases, very little is known for its expression in intracranial tumors. In the present study, 73 intracranial tumor samples were examined for KLK6 messenger ribunucleic acid (mRNA) gene expression using quantitative real-time polymerase chain reaction. Statistical analysis revealed the significant association of KLK6 expression with clinical and pathological parameters. Follow-up information was available for a median time of 20?months (range 1-59?months). KLK6 is expressed more frequently in tumors of high malignancy like the glioblastomas (70.6?%) and less in tumors of low malignancy like the meningiomas (12.5?%). KLK6 positive expression is associated with tumor grade (p?相似文献   

Parallel overexpression of seven kallikrein genes in ovarian cancer

Recent evidence suggests that many members of the human kallikrein (KLK) gene family are differentially regulated in ovarian cancer and have potential as diagnostic and/or prognostic markers. We used the serial analysis of gene expression and expressed sequence tag databases of the Cancer Genome Anatomy Project to perform in silico analyses of the expression pattern of the 15 human KLK genes in normal and cancerous ovarian tissues and cell lines. We found that seven KLK genes (KLK5, KLK6, KLK7, KLK8, KLK10, KLK11, and KLK14) are up-regulated in ovarian cancer. Probing 2 normal and 10 ovarian cancer serial analysis of gene expression libraries with gene-specific tags for each KLK indicated that whereas no expression was detected in any normal libraries (with the exception of KLK10 and KLK11), these KLKs were found to be expressed with moderate densities (103-408 tags per million) in 40-60% of the ovarian cancer libraries analyzed. These data were verified by screening the expressed sequence tag databases, where 78 of 79 mRNA clones isolated for these genes were from ovarian cancer libraries. X-profiler comparison of the pools of normal and cancerous ovaries identified a significant difference in expression levels for six of the seven KLKs. We experimentally verified the overexpression of six KLK proteins in cancer versus normal or benign tissues with highly sensitive and specific immunofluorometric assays. A statistically significant stepwise increase in protein levels was found among normal, benign, and cancerous ovarian tissues. The expression of five KLKs showed a strong degree of correlation at the protein level, suggesting the existence of a common mechanism or pathway that controls the expression of this group of adjacent genes during ovarian cancer progression.     

卵巢癌中 ECRG4基因启动子甲基化的研究

目的：探讨人食管癌相关基因4（esophageal cancer related gene 4,ECRG4）基因启动子区域在卵巢癌组织中的甲基化状态及临床意义。方法：应用甲基化特异性 PCR 检测 ECRG4基因启动子在50例卵巢癌组织和10例正常卵巢组织中的甲基化状态并结合临床病理资料进行分析。结果：在卵巢癌组织中 ECRG4甲基化阳性率为36%（18/50）,正常卵巢组织未出现 ECRG4甲基化。ECRG4甲基化与肿瘤淋巴结转移及 Ki -67表达密切相关（P <0.05）。结论：ECRG4甲基化可能是参与卵巢癌发展的重要分子事件。     

Prognostic value of kallikrein-related peptidase 6 protein expression levels in advanced ovarian cancer evaluated by automated quantitative analysis (AQUA)

Kallikrein-related peptidases, a subgroup of the serine protease enzyme family, are considered important prognostic biomarkers in cancer. In the present study, we sought to determine the prognostic value of kallikrein-related peptidase 6 (KLK6) in ovarian cancer using a novel method of compartmentalized in situ protein analysis. A tissue array composed of 150 advanced stage ovarian cancers, uniformly treated with surgical debulking followed by platinum-paclitaxel combination chemotherapy, was constructed. For evaluation of KLK6 protein expression, we used an immunofluorescence-based method of automated in situ quantitative measurement of protein analysis (AQUA). Mean follow-up time of the cohort was 34.35 months. One hundred and thirty-five of 150 cases had sufficient tissue for AQUA analysis. In univariate survival analysis, low tumor KLK6 expression was associated with better outcome for overall survival over 3 years (P = 0.019). There was no association between tumor KLK6 expression and progression-free survival (P = 0.128). In multivariate survival analysis, adjusting for well-characterized prognostic variables, low tumor KLK6 expression level was one of the most significant predictor variable for overall survival (95% confidence interval, 1.19-3.50; P = 0.009). High tumor KLK6 protein expression is associated with inferior patient outcome in ovarian cancer. KLK6 may represent a promising disease biomarker and therapeutic target in ovarian cancer.     

Expression of human Kallikrein 14 (KLK14) in breast cancer is associated with higher tumour grades and positive nodal status

Human kallikrein 14 (KLK14) is a steroid hormone-regulated member of the tissue kallikrein family of serine proteases, for which a prognostic and diagnostic value in breast cancer has been suggested. To further characterise the value of KLK14 as a breast tumour marker, we have carefully analysed KLK14 expression in normal breast tissue and breast cancer both on the RNA level by real-time RT-PCR (n = 39), and on the protein level (n = 127) using a KLK14-specific antibody for immunohistochemistry. We correlated KLK14 protein expression data with available clinico-pathological parameters (mean follow-up time was 55 months) including patient prognosis. KLK14 RNA expression as quantified by real-time RT-PCR was significantly more abundant in breast tumours compared to normal breast tissue (P = 0.027), an issue that had not been clarified recently. Concordantly with the RNA data, cytoplasmic KLK14 protein expression was significantly higher in invasive breast carcinomas compared to normal breast tissues (P = 0.003). Furthermore, KLK14 protein expression was associated with higher tumour grade (P = 0.041) and positive nodal status (P = 0.045) but was not significantly associated with shortened disease-free or overall patient survival time in univariate analyses. We conclude that KLK14 is clearly overexpressed in breast cancer in comparison to normal breast tissues and is positively associated with conventional parameters of tumour aggressiveness, but due to a missing association with survival times, the use of KLK14 immunohistochemistry as a prognostic marker in breast cancer is questionable.     

KLK6 and KLK13 predict tumor recurrence in epithelial ovarian carcinoma

Background:

The human kallikrein-related peptidase family consists of 15 genes. Twelve of these genes are overexpressed in ovarian cancer and may represent potential markers for diagnosis, prognosis, and/or response to treatment. The aim of this study was to determine the prognostic significance of kallikrein-related peptidase 6 (KLK6) and kallikrein-related peptidase 13 (KLK13) in epithelial ovarian cancer by quantifying gene expression levels with tumour pathology and patient survival data.

Methods:

Total RNA was isolated from 106 patients diagnosed with primary ovarian cancer, as well as 8 normal ovary controls. Samples were analysed by quantitative real-time PCR for KLK6 and KLK13 expression. Correlation between kallikrein gene expression and clinical characteristics was evaluated with the χ²-test. Survival analysis was performed using Kaplan–Meier and Cox proportional hazards regression models.

Results:

Expression levels of both KLK6 and KLK13 mRNA were significantly increased in invasive cancers relative to normal ovaries (P=0.002 and 0.039 respectively). High KLK6 and KLK13 expression was an indicator of poor prognosis, with patients having a shorter recurrence-free survival (P=0.002 and 0.027 respectively). High KLK6 expression was also significantly associated with lower overall survival (P=0.011). When subjected to multivariate analysis, patients with either high KLK6 or KLK13 were 3- and 2.2-fold, respectively, more likely to have a recurrence than patients with low kallikrein expression.

Conclusion:

These data show increased mRNA expression of KLK6 and KLK13 in ovarian cancer compared to normal ovarian tissues. High KLK6 or KLK13 expression in primary ovarian tumours can significantly predict prognosis in terms of recurrence-free survival and overall survival. In all, this study shows KLK6 and KLK13 as potential biomarkers and may be therapeutic targets for treatment of ovarian cancer.