Prostatic Neoplasms: Klee GG

Sturgeon CM, Duffy MJ, Stenman UH, Lilja H, Brünner N, Chan DW, Babaian R, Bast RC, Dowell B, Esteva FJ, Haglund C, Harbeck N, Hayes DF, Holten-Andersen M, Klee GG, Lamerz R, Looijenga LH, Molina R, Nielsen HJ, Rittenhouse H, Semjonow A, Shih IeM, Sibley P, Sölétormos G, Stephan C, Sokoll L, Hoffman BR, Diamandis EP, Anonymous00039. · Department of Clinical Biochemistry, Royal Infirmary of Edinburgh, Edinburgh, UK. · Clin Chem. · Pubmed #19042984 No free full text.

Abstract: BACKGROUND: Updated National Academy of Clinical Biochemistry (NACB) Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed. METHODS: Published reports relevant to use of tumor markers for 5 cancer sites--testicular, prostate, colorectal, breast, and ovarian--were critically reviewed. RESULTS: For testicular cancer, alpha-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase are recommended for diagnosis/case finding, staging, prognosis determination, recurrence detection, and therapy monitoring. alpha-Fetoprotein is also recommended for differential diagnosis of nonseminomatous and seminomatous germ cell tumors. Prostate-specific antigen (PSA) is not recommended for prostate cancer screening, but may be used for detecting disease recurrence and monitoring therapy. Free PSA measurement data are useful for distinguishing malignant from benign prostatic disease when total PSA is <10 microg/L. In colorectal cancer, carcinoembryonic antigen is recommended (with some caveats) for prognosis determination, postoperative surveillance, and therapy monitoring in advanced disease. Fecal occult blood testing may be used for screening asymptomatic adults 50 years or older. For breast cancer, estrogen and progesterone receptors are mandatory for predicting response to hormone therapy, human epidermal growth factor receptor-2 measurement is mandatory for predicting response to trastuzumab, and urokinase plasminogen activator/plasminogen activator inhibitor 1 may be used for determining prognosis in lymph node-negative patients. CA15-3/BR27-29 or carcinoembryonic antigen may be used for therapy monitoring in advanced disease. CA125 is recommended (with transvaginal ultrasound) for early detection of ovarian cancer in women at high risk for this disease. CA125 is also recommended for differential diagnosis of suspicious pelvic masses in postmenopausal women, as well as for detection of recurrence, monitoring of therapy, and determination of prognosis in women with ovarian cancer. CONCLUSIONS: Implementation of these recommendations should encourage optimal use of tumor markers.

Partin AW, Catalona WJ, Finlay JA, Darte C, Tindall DJ, Young CY, Klee GG, Chan DW, Rittenhouse HG, Wolfert RL, Woodrum DL. · Department of Urology, Johns Hopkins Hospital, Baltimore, Maryland, USA. · Urology. · Pubmed #10565744 No free full text.

Abstract: OBJECTIVES: Human glandular kallikrein 2 (hK2) and prostate-specific antigen (PSA) are members of a multigene family of serine proteases that share approximately 80% sequence homology. Both are expressed in the prostate epithelium, are under androgen regulation, are present in serum and seminal fluid, and can form complexes with endogenous protease inhibitors (eg, alpha2-macroglobulin and alpha1-antichymotrypsin). Differences in immunohistochemistry and substrate specificity suggest hK2 may provide unique information for early detection and characterization of prostate cancer. METHODS: Nine hundred thirty-seven archived serum samples from men treated at two academic institutions were studied. All men underwent biopsy, had a histologically confirmed diagnosis of cancer or noncancer, and a total PSA level greater than 2 ng/mL. Samples were tested in Hybritech's Tandem-R PSA and Tandem-R free PSA (fPSA) assays and a research prototype assay for total hK2 (thK2). RESULTS: The thK2/fPSA ratio provided additional specificity for cancer detection over PSA and the percentage of fPSA (%fPSA). A model for cancer detection using %fPSA and the thK2/fPSA ratio when PSA is 2 to 4 ng/mL is proposed that would identify as many as 40% of the cancers and would require biopsy in only 16.5% of the men in this PSA range. CONCLUSIONS: In this study, %fPSA and thK2/fPSA provided unique information for prostate cancer detection and increased the specificity of cancer detection.

Klee GG, Goodmanson MK, Jacobsen SJ, Young CY, Finlay JA, Rittenhouse HG, Wolfert RL, Tindall DJ. · Departments of Laboratory Medicine and Pathology, Epidemiology, and Urology Research, Mayo Clinic and Mayo Foundation, 200 First Street SW, Rochester, MN 55905, USA. · Clin Chem. · Pubmed #10351988 links to  free full text

Abstract: BACKGROUND: Human glandular kallikrein (hK2) is a serine protease that has 79% amino acid identity with prostate-specific antigen (PSA). Both free hK2 and hK2 complexed to alpha1-antichymotrypsin (ACT) are present in the blood in low concentrations. We wished to measure hK2 in serum with limited contribution from hK2-ACT for the results. Methods: We developed an automated assay for hK2 with use of a select pair of monoclonal antibodies. The prototype assay was implemented on a Beckman Coulter ACCESS(R) analyzer. RESULTS: The detection limit of the assay was 1.5 ng/L, the "functional sensitivity" (day-to-day CV <15%) was <4 ng/L, cross-reactivity with PSA and PSA-ACT was negligible, and cross-reactivity with hK2-ACT was 2%. After surgical removal of prostate glands, serum hK2 was <7 ng/L and was <15 ng/L in most healthy women. The median serum concentration of hK2 in healthy men without prostate cancer was 26 ng/L. The median concentration of hK2 was 72 ng/L for men having prostate cancer with lower Gleason scores compared with 116 ng/L for men with more advanced cancer. The concentration of hK2 correlated weakly with PSA, with the mean hK2 concentrations generally 30- to 80-fold lower than PSA concentrations. CONCLUSION: The availability of a robust, high sensitivity automated assay for hK2 should facilitate further investigations of the role of hK2 measurements in the management of patients with prostate disease.

Nakagawa T, Kollmeyer TM, Morlan BW, Anderson SK, Bergstralh EJ, Davis BJ, Asmann YW, Klee GG, Ballman KV, Jenkins RB. · Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States of America. · PLoS One. · Pubmed #18846227 links to  free full text

Abstract: BACKGROUND: Many men develop a rising PSA after initial therapy for prostate cancer. While some of these men will develop a local or metastatic recurrence that warrants further therapy, others will have no evidence of disease progression. We hypothesized that an expression biomarker panel can predict which men with a rising PSA would benefit from further therapy. METHODOLOGY/PRINCIPAL FINDINGS: A case-control design was used to test the association of gene expression with outcome. Systemic (SYS) progression cases were men post-prostatectomy who developed systemic progression within 5 years after PSA recurrence. PSA progression controls were matched men post-prostatectomy with PSA recurrence but no evidence of clinical progression within 5 years. Using expression arrays optimized for paraffin-embedded tissue RNA, 1021 cancer-related genes were evaluated-including 570 genes implicated in prostate cancer progression. Genes from 8 previously reported marker panels were included. A systemic progression model containing 17 genes was developed. This model generated an AUC of 0.88 (95% CI: 0.84-0.92). Similar AUCs were generated using 3 previously reported panels. In secondary analyses, the model predicted the endpoints of prostate cancer death (in SYS cases) and systemic progression beyond 5 years (in PSA controls) with hazard ratios 2.5 and 4.7, respectively (log-rank p-values of 0.0007 and 0.0005). Genes mapped to 8q24 were significantly enriched in the model. CONCLUSIONS/SIGNIFICANCE: Specific gene expression patterns are significantly associated with systemic progression after PSA recurrence. The measurement of gene expression pattern may be useful for determining which men may benefit from additional therapy after PSA recurrence.

He W, Kularatne SA, Kalli KR, Prendergast FG, Amato RJ, Klee GG, Hartmann LC, Low PS. · Department of Chemistry, Purdue University, West Lafayette, IN 47906, USA. · Int J Cancer. · Pubmed #18661519 No free full text.

Abstract: Quantitation of circulating tumor cells (CTCs) can provide information on the stage of a malignancy, onset of disease progression and response to therapy. In an effort to more accurately quantitate CTCs, we have synthesized fluorescent conjugates of 2 high-affinity tumor-specific ligands (folate-AlexaFluor 488 and DUPA-FITC) that bind tumor cells >20-fold more efficiently than fluorescent antibodies. Here we determine whether these tumor-specific dyes can be exploited for quantitation of CTCs in peripheral blood samples from cancer patients. A CTC-enriched fraction was isolated from the peripheral blood of ovarian and prostate cancer patients by an optimized density gradient centrifugation protocol and labeled with the aforementioned fluorescent ligands. CTCs were then quantitated by flow cytometry. CTCs were detected in 18 of 20 ovarian cancer patients (mean 222 CTCs/ml; median 15 CTCs/ml; maximum 3,118 CTCs/ml), whereas CTC numbers in 16 gender-matched normal volunteers were negligible (mean 0.4 CTCs/ml; median 0.3 CTCs/ml; maximum 1.5 CTCs/ml; p < 0.001, chi(2)). CTCs were also detected in 10 of 13 prostate cancer patients (mean 26 CTCs/ml, median 14 CTCs/ml, maximum 94 CTCs/ml) but not in 18 gender-matched healthy donors (mean 0.8 CTCs/ml, median 1, maximum 3 CTC/ml; p < 0.0026, chi(2)). Tumor-specific fluorescent antibodies were much less efficient in quantitating CTCs because of their lower CTC labeling efficiency. Use of tumor-specific fluorescent ligands to label CTCs in peripheral blood can provide a simple, accurate and sensitive method for determining the number of cancer cells circulating in the bloodstream.

Klee EW, Finlay JA, McDonald C, Attewell JR, Hebrink D, Dyer R, Love B, Vasmatzis G, Li TM, Beechem JM, Klee GG. · Mayo Clinic, 315 Stabile Building, Rochester, MN 55904, USA. · Clin Chem. · Pubmed #18061989 links to  free full text

This publication has no abstract.

Finlay JA, Klee EW, McDonald C, Attewell JR, Hebrink D, Dyer R, Love B, Vasmatzis G, Li TM, Beechem JM, Klee GG. · Invitrogen Corporation, 5781 Van Allen Way, Carlsbad, CA 92008, USA. · Clin Chem. · Pubmed #18061988 links to  free full text

This publication has no abstract.

Kube DM, Savci-Heijink CD, Lamblin AF, Kosari F, Vasmatzis G, Cheville JC, Connelly DP, Klee GG. · Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA. <> · BMC Mol Biol. · Pubmed #17376245 links to  free full text

Abstract: BACKGROUND: To discover prostate cancer biomarkers, we profiled gene expression in benign and malignant cells laser capture microdissected (LCM) from prostate tissues and metastatic prostatic adenocarcinomas. Here we present methods developed, optimized, and validated to obtain high quality gene expression data. RESULTS: RNase inhibitor was included in solutions used to stain frozen tissue sections for LCM, which improved RNA quality significantly. Quantitative PCR assays, requiring minimal amounts of LCM RNA, were developed to determine RNA quality and concentration. SuperScript II reverse transcriptase was replaced with SuperScript III, and SpeedVac concentration was eliminated to optimize linear amplification. The GeneChip(R) IVT labeling kit was used rather than the Enzo BioArray HighYield RNA transcript labeling kit since side-by-side comparisons indicated high-end signal saturation with the latter. We obtained 72 mug of labeled complementary RNA on average after linear amplification of about 2 ng of total RNA. CONCLUSION: Unsupervised clustering placed 5/5 normal and 2/2 benign prostatic hyperplasia cases in one group, 5/7 Gleason pattern 3 cases in another group, and the remaining 2/7 pattern 3 cases in a third group with 8/8 Gleason pattern 5 cases and 3/3 metastatic prostatic adenocarcinomas. Differential expression of alpha-methylacyl coenzyme A racemase (AMACR) and hepsin was confirmed using quantitative PCR.

Bondar OP, Barnidge DR, Klee EW, Davis BJ, Klee GG. · Department of Laboratory Medicine and Pathology, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA. · Clin Chem. · Pubmed #17317883 links to  free full text

Abstract: BACKGROUND: Zn-alpha2 glycoprotein (ZAG) is a relatively abundant glycoprotein that has potential as a biomarker for prostate cancer. We present a high-flow liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measuring serum ZAG concentrations by proteolytic cleavage of the protein and quantification of a unique peptide. METHODS: We selected the ZAG tryptic peptide (147)EIPAWVPEDPAAQITK(162) as the intact protein for quantification and used a stable isotope-labeled synthetic peptide with this sequence as an internal standard. Standards using recombinant ZAG in bovine serum albumin, 50 g/L, and a pilot series of patient sera were denatured, reduced, alkylated, and digested with trypsin. The concentration of ZAG was calculated from a dose-response curve of the ratio of the relative abundance of the ZAG tryptic peptide to internal standard. RESULTS: The limit of detection for ZAG in serum was 0.08 mg/L, and the limit of quantification was 0.32 mg/L with a linear dynamic range of 0.32 to 10.2 mg/L. Replicate digests from pooled sera run during a period of 3 consecutive days showed intraassay imprecision (CV) of 5.0% to 6.3% and interassay imprecision of 4.4% to 5.9%. Mean (SD) ZAG was higher in 25 men with prostate cancer [7.59 (2.45) mg/L] than in 20 men with nonmalignant prostate disease [6.21 (1.65) mg/L, P = 0.037] and 6 healthy men [3.65 (0.71) mg/L, P = 0.0007]. CONCLUSIONS: This LC-MS/MS assay is reproducible and can be used to evaluate the clinical utility of ZAG as a cancer biomarker.

Bock JL, Klee GG. · Department of Pathology, Stony Brook University, Stony Brook, NY, USA. · Arch Pathol Lab Med. · Pubmed #14987148 No free full text.

Abstract: Assays are now available that can measure very low concentrations of prostate-specific antigen (PSA), but their analytic performance and clinical utility are not well defined. This brief article highlights some of the clinical issues related to the limited prognostic significance of small changes in PSA concentrations in men with prostate cancer who have been treated with prostate ablation therapy. College of American Pathologists proficiency survey data are presented, illustrating the performance of commercial PSA assays with low PSA concentration survey samples tested between 1998 and 2002. The performance of the assays appears to be improving, but many of the currently used assays have intralaboratory coefficients of variation greater than 20% for PSA concentrations less than 0.4 ng/mL. Also, there are major differences in the level of PSA reported by various assays in these low concentration samples. These level differences (if they are also seen in clinical samples) may cause clinical problems when fixed serum PSA thresholds (eg, 0.2 ng/mL) are used to make clinical decisions related to prostate tumor recurrence.

Go RS, Klee GG, Richardson RL. · Divisions of Medical Oncology, and Laboratory Medicine and Pathology, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA. · J Urol. · Pubmed #10893618 No free full text.

This publication has no abstract.

Darson MF, Pacelli A, Roche P, Rittenhouse HG, Wolfert RL, Saeid MS, Young CY, Klee GG, Tindall DJ, Bostwick DG. · Department of Urology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA. · Urology. · Pubmed #10223487 No free full text.

Abstract: OBJECTIVES: To describe the expression of a potential new tumor marker, human glandular kallikrein 2 (hK2), in primary adenocarcinoma and lymph node metastases that may be useful as an adjunct to prostate-specific antigen (PSA) in the diagnosis and monitoring of prostate cancer. METHODS: We evaluated 151 radical prostatectomy specimens removed at Mayo Clinic with node-positive adenocarcinoma to compare cytoplasmic expression of hK2, pro-hK2, and PSA in benign tissue, prostate adenocarcinoma, and lymph node metastases. Monoclonal antibodies for mature hK2 (hK2-G586), pro-hK2 (pro-hK2-G464), and PSA (PSA-773) were used. A polyclonal antibody for PSA was also used. Immunoreactivity in each case was tested to determine whether cancer recurrence could be predicted. RESULTS: Intense epithelial cytoplasmic immunoreactivity was observed in every case for hK2-G586, pro-hK2-G464, PSA-773, and polyclonal PSA (100% of cases, respectively). The intensity and extent of hK2 expression was greater in lymph node metastases than in primary cancer; furthermore, the expression in primary cancer was greater than in benign epithelium. Pro-hK2 was expressed in a greater percentage of cells in primary cancer than in benign tissue; furthermore, pro-hK2 was expressed to a greater extent in primary cancer than in lymph node metastases. In marked contrast to mature hK2, monoclonal PSA immunoreactivity was expressed to a higher extent in primary cancer than in lymph node metastases. Polyclonal PSA showed an incremental increase in expression from benign tissue to primary cancer and a further increase in expression in lymph node metastases. CONCLUSIONS: hK2 was expressed in every cancer, and the expression incrementally increased from benign epithelium to primary cancer and lymph node metastases. Pro-hK2 was expressed to the greatest extent in primary cancer. Monoclonal PSA displayed inverse immunoreactivity compared with hK2. Polyclonal PSA showed incremental increases, suggesting that both hK2 and PSA were being detected. Tissue expression of hK2 appears to be regulated independently of PSA in benign epithelium, adenocarcinoma, and lymph node metastases.

Zhang S, Hsieh ML, Zhu W, Klee GG, Tindall DJ, Young CY. · Department of Urology, Mayo Graduate School, Mayo Clinic/Foundation, Rochester, Minnesota 55905, USA. · Endocrinology. · Pubmed #10098501 links to  free full text

Abstract: T3 plays an important role in the regulation of cell growth and differentiation. In this study, we show the interactive effects of T3 and androgens on the growth response and expression of the prostate-specific genes, PSA (prostate-specific antigen) and hK2 (human glandular kallikrein), in the human prostate cancer cell line, LNCaP. T3 alone showed pronounced growth enhancement in a dose-dependent fashion. However, in the presence of androgens, higher concentrations of T3 were required to produce additional proliferative effects. T3, androgens, or a combination of the two up-regulated PSA protein production in a dose-dependent fashion, but T3 had little stimulatory effect on hK2 protein expression, regardless of the presence or absence of androgens. Using gene transfer assays, T3 alone showed no effect on transcriptional activation of a reporter gene mediated by the PSA or hK2 enhancer/promoters. T3 potentiated the androgen-mediated transcription of the PSA gene but not that of the hK2 gene. A previous study suggested that the T3 effect on PSA protein expression was caused by an up-regulation of the androgen receptor (AR) protein by T3. Our results contradict these. Although AR expression was increased by T3 alone, Western blot analysis showed that the total cellular AR level was not further increased by T3 in the presence of androgens, in comparison with cells stimulated by androgens alone. Both Western blot analysis and a gel DNA band shift assay revealed that nuclear AR was not increased by T3. This study suggests that transcription factor(s) other than the AR may mediate T3 enhancement of androgenic induction of PSA expression.