[CANCER RESEARCH 48, 6938-6942, December 1, 1988] Immunohistochemical Characterization of Two Monoclonal Antibodies, P25.48 and P25.91, Which Define a New Prostate-specific Antigen1

Michel Bazinet,2 Richard J. Cote, Carlos Cordon-Cardo, Andrzej Myc, William R. Fair, and Lloyd J. Old

Departments of Human Tumor Immunology, Pathology, and Urology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021

ABSTRACT Tissue Culture. Cultured lines of different human cancers were ob tained from the collection of J. Fogli and from the laboratory of Human We have generated two new mouse monoclonal antibodies against Tumor Immunology, Sloan-Kettering Institute, New York. The pros prostate cancer. P25.48 (IgG3) and P25.91 (IgG2a) were derived from a tate cancer cell lines PC-3 (17), DU-145 (18), and LNCaP (19) were fusion using fresh prostate cancer cells as the immunogen. Initial screen obtained from the American Tissue Culture Collection, Rockville, MD. ing was performed by indirect immunofluorescence on frozen tissue The established cell lines were cultured in modified Eagle's medium sections of prostate cancer specimens. The specificity analysis was per supplemented with 7.5% FCS, 0.1 HIMnonessential amino acids, 2 mM formed by indirect immunoperoxidase on frozen sections of normal tissues L-glutamine, 100 units of penicillin/ml, and 100 tig of streptomycin/ and benign and malignant prostate tissues. ml (all from GIBCO, Grand Island, NY). Hybridomas were initially P25.48 and P2S.91 did not react with any benign prostatic tissues (0 cloned in medium consisting of RPMI-1640 medium supplemented of 17), but reacted with a subset of the malignant prostatic tissues. Five with 10% FCS, 0.1 mM nonessential amino acids, 2 mM L-glutamine, specimens of well-differentiated carcinoma were tested and did not react 100 units of penicillin/ml, 100 Mg of streptomycin/ml, 50 ¡MI2- with P25.48 or with P25.91. Of 16 higher grade specimens, nine reacted mercaptoethanol, and HAT medium (GIBCO, Grand Island, NY). with both P25.48 and P25.91, one reacted with P2S.48 only, and one Subcloning was done in HT medium. reacted with P25.91 only. In most positive cases, the reactivity was Mouse Monoclonal Antibody Production. MABs P25.48 and P25.91 heterogenous. resulted from a fusion of mouse myeloma cells (NS-1 ) with spleen cells P25.48 and P25.91 showed a very restricted pattern of reactivity in from a female BALB/c x CBY mouse that had been immunized with nonprostatic tissues. Of 50 normal specimens, only one breast specimen a mechanically obtained cell suspension from a fresh prostate cancer showed some reactivity. None of the nine fetal tissues or of the IS specimen (P251). This tumor was histológica!Iy classified as moderately malignant tissues tested reacted with these monoclonal antibodies. to poorly differentiated carcinoma. The immunization was performed The pattern of reactivity of P2S.48 and P25.91 suggests that they with 1 x 10" cells suspended in 0.6 ml of PBS and injected i.p. without recognize the same antigen. This antigen is selectively expressed by adjuvant. No boosting injection was done. Five days after the immuni malignant prostatic epithelium. In addition, it appears to be distinct from zation, the mouse spleen cells were harvested and fused with the NS-1 all other previously described prostate cancer-associated antigens. mouse myeloma cells in a 2:1 ratio (splenocytes:myeloma) with poly ethylene glycol (M, 4000) as previously described (20). The hybridomas were cloned in HAT medium. Three wk later, supernatants were INTRODUCTION screened for reactivity by IIF on frozen tissue sections of P251. MABs P25.48 and P25.91 hybridomas were then subcloned 3 times by limiting Mouse monoclonal antibody technology has been used to characterize antigens expressed by prostatic epithelium (1-13) dilution in HT medium. They were subsequently grown in RPMI plus 10% FCS. Undiluted supernatants from these cultures were used as the (Table 1). Most of the antigens described so far are expressed source of MABs for all IIF and indirect immunoperoxidase studies. by both benign and malignant prostatic tissues, and the level of They contained 15 to 25 ng of immunoglobulins per ml. antigen expression usually decreases in higher grade prostate Serological Procedures. Resetting assays for the detection of cell cancer specimens (14-16). surface antigens using rabbit anti-mouse immunoglobulin or Protein A In the present study, we describe 2 new mouse MABs,3 conjugated to human O erythrocytes were performed as described (21, P25.48 and P25.91, which recognize an antigen that appears 22). IIF assays for the detection of intracellular antigens were done on to be selectively expressed by malignant prostatic epithelium. fixed cells (fixation by cold acetone or 10% formaldehyde followed by 10% Nonidet P-40 detergent) with hybridoma culture supernatants and fluorescein isothiocyanaie conjugated rabbit anti-mouse IgG (1:40 di MATERIALS AND METHODS lution) (Cappel Laboratories, Cochranville, PA). Analysis of immuno globulin subclasses was performed by Ouchterlony immunodiffusion Human Tissues. Fresh specimens of benign and malignant prostate assay. tissues were provided from surgical cases by the Tumor Procurement Indirect Immunofluorescence. Cryostat cut tissue sections (6 to 8 ¡an Center from the Department of Pathology at the Memorial Sloan- thick) were fixed for 10 min in cold acetone and washed in PBS. Kettering Cancer Center. Specimens of normal tissues and other types Undiluted hybridoma supernatant was then added for l h at room of cancer were obtained in the same manner or (rarely) from autopsy temperature in a humidified chamber. Tissue sections were washed with material no more than 8 h following the time of death. Fetal tissues PBS and incubated for 45 min with fluoresceinated rabbit anti-mouse were obtained from elective abortions. On receipt, specimens were immunoglobulin at 1:40 dilution in PBS (Cappel Laboratories, Coch snap-frozen in liquid nitrogen, submerged in OCT embedding com ranville, PA). Tissue sections were washed extensively in PBS, mounted pound in cryomolds, and stored until use at —¿70°C. in Gelvatol (Monsanto, Springfield, MA), and examined with an epi- fluorescence microscope. IIF was performed on mononuclear cells from Received 2/16/88; revised 8/24/88; accepted 8/29/88. The costs of publication of this article were defrayed in part by the payment bone marrow aspirations of normal individuals as previously described of page charges. This article must therefore be hereby marked advertisement in (23). accordance with 18 U.S.C. Section 1734 solely to indicate this fact. Indirect Immunoperoxidase (Fig. 1). Cryostat cut tissue sections (4 to 1Funding for this work was provided in part by the Oliver S. and Jennie R. 8 ;

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Table 1 Characteristics of previously described MABs defining prostatic antigens MABs (immunoglobulin class)Multiples antigensPAP, (réf.)Lillehoj MABsDefined M, 102,000 proteinCharacteristicsProstatespecific, strongly expressed in (1)Nadji «1a/. BPH," heterogeneous in higher grade et al. (2) prostate tumorsAuthors Naritoku et al. (3)

FS(IgGl) PSA, M, 36,000 glyco- As above Papsidero et al. (4) protein

IF3, 2G7, lCS(IgGl) As above As above Franke! et al. (5)

KR-P8(IgGl) M, 48,000-75,000 glyco- Similar to PAP and PSA, prostate spe Raynor et al. (6, 7) protein cific, react with PC-3 and DU-145

TURP-27 (IgG3) Not described Similar to PAP and PSA but reacts with Starling et al. (8) central nervous system and peripheral nerves*; no reactivity with prostate cell lines

TURP-73 (IgG2a) Not described Antigen expressed strongly in prostatic Starling et al. (8) tissues but also present in other normal tissues; react with PC-3, DU-145, and LNCaP

«PR03 (IgG2a) p54, M, 54,000 protein Higher expression in prostate cancer than Ware et al. (9) in benign prostatic tissues; also ex pressed in nonprostatic tissues; react with PC-3

«PROS(?) As above As above; recognize a different epitope Webb et al. (10) on p54

P6.2 (IgM) Not described Not expressed in BPH; reacts with 68% Wright et al. (12, 13) of prostate cancers tested, PC-3 and bladder cell lines, and with renal proxi mal tubules

DU 83.21 (IgM) M, 28,000 and 60,000 Not expressed in BPH; reacts with 58% Wright étal.(12, 13) components; glycopro- of prostate cancers tested, PC-3, DU- 145, bladder cell lines, and with renal proximal tubules " BPH, benign prostatic hyperplasia. * M. Bazinet and R. J. Cote, unpublished data. peroxidase-conjugated goat anti-mouse IgG diluted 1:50 in PBS and grew well in nude mice. MABs P25.48 and P25.91 were (TACO, Inc., Burlingame, CA) for 45 min. After subsequent washing, determined to be IgG3 and IgG2a, respectively, by Ouchterlony the slides were incubated with the chromogen DAB (Sigma, St. Louis, immunodiffusion assay. MO) for 5 min (0.2% DAB and 0.001% H2O2 in distilled water). After Reactivity on Normal and Fetal Tissues. A panel of SOnormal treatment, sections were washed with distilled water, counterstained tissues from a variety of different sources was tested by IIP with hematoxylin, dehydrated, and mounted with Permount. Fluorescence-activated Flow Cytometry Evaluation of Peripheral (Table 2). None of these tissues expressed the antigen recog Blood Mononuclear Cells. Fifty-Mi aliquots of lymphocyte suspensions nized by MABs P25.48 or P25.91 except for one breast tissue were incubated with appropriate MABs for 30 min on ice. After specimen where only a scanty number of cells showed reactivity incubation, cells were washed once and incubated with goat anti-mouse with both MABs. IgG conjugated to fluorescein isothiocyanate for 30 min. Cells were Fetal tissues from 8 different sources were evaluated by IIP then washed and resuspended in 1 ml of Hanks' buffered saline solution (Table 3). None of these expressed the antigens recognized by for the surface IF analysis. P25.48orP25.91. Leukocytes stained were analyzed on Spectrum III laser flow cytom- Reactivity with Normal and Benign Prostatic Tissues. Seven etry (Ortho Diagnostics, Westwood, MA) to determine leukocyte sub- teen specimens were tested by IIP with both P25.48 and P25.91 populations and the percentage of positive cells for particular antibody (Table 4). No reactivity was found in stroma or epithelium. In (24, 25). 2 cases, weak reactivity with secretions was found in some glands while the epithelium remained negative. In one of those RESULTS 2 cases, the benign specimen was obtained from a prostate gland containing prostatic adenocarcinoma in the opposite lobe. Selection of MABs P25.48 and P25.91. MABs were initially In the other case, there was no apparent clinical or pathological screened for their reactivities (IIP) on frozen tissue sections of evidence of cancer in the specimen obtained. the tumor used as the immunogen. MABs showing strong In specimens of prostatic carcinoma reactive with P25.48 reactivity were then evaluated by IIP on a panel of normal and/or P25.91, the adjacent normal prostatic epithelium, when tissues including kidney, colon, and liver (data not shown). present, remained negative. Hybridomas producing MABs not reactive with the normal Reactivity with Malignant Prostatic Tissues. MABs P2S.48 tissues were then subcloned and expanded for further evalua and P25.91 were tested by IIP on frozen tissue sections of tion. The two hybridomas selected by the screening procedure different prostate cancer specimens (Table 5). These specimens were stable for antibody secretion in long-term tissue culture were divided in 4 groups according to their degree of differen- 6939 Downloaded from cancerres.aacrjournals.org on September 26, 2021. © 1988 American Association for Cancer Research. DEFINITION BY MABs P25.48 AND P25.91 OF A PROSTATE-SPECIFIC ANTIGEN

Table 2 Reactivity ofP25.48 and P25.9I with normal adult tissues (by indirect immunoperoxidase assay)

SpecimensLungBronchusLiverStomachJejunumColonSalivaryPancreasThyroidAdrenalKidneyUreterBladderSeminaltested31241322124162122111112111144P25.48P25.91— '—¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” vésiculeVas —¿â€” deferensTestisOvaryFallopian —¿â€” —¿â€” —¿â€” tubeUterusCervixEndometriumMyometriumPlacentaBreastSkinLymph—¿â€” B —¿â€” V —¿â€” —¿Â» »— —¿â€” nodePeripheral —¿â€” nerveCerebral —¿â€” cortexPeripheral —¿C cells)Bone blood (mononuclear C—c marrow (mononuclear cells)No. —¿' —¿,noreactivity. * Some ducts showed strong reactivity in one of 2 specimens. ' Fluorescence-activated flow cytometry.

Table 3 Reactivity O/P25.48 and P25.9I with fetal tissues (by indirect immunoperoxidase assay) No. FetalP25.91Brain tissues tested P25.48 B —¿HeartLiverSpleenKidneyPancreasColonSkin—2 —¿Â° —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿â€” —¿ —¿,noreactivity.

Table 4 Reactivity ofP25.4S and P25.91 with normal prostate epithelium and benign prostatic hyperplasia (by indirect immunoperoxidase assay) Specimens P25.48 P25.91 Normal prostate epithelium P12I Fig. 1. Indirect immunoperoxidase staining of P301 prostatic adenocarci- P21I noma. Tissue obtained from a radical prostatectomy specimen. Indirect immu BPHC COOBB—¿P6I noperoxidase staining on frozen tissue sections, a, reactivity with PSA (F5). Note —¿PHI staining in both benign (A) and malignant epithelium (A/). />.reactivity with MAB —¿P14I P2S.48. Note staining of malignant epithelium (M), while the benign epithelium —¿P15I (B) remains unstained, c, reactivity with MAB P25.91. Note staining of malignant epithelium (M), while the benign epithelium (/>')remains unstained. —¿PI8I —¿P19I —¿P26I tiation. Five well-differentiated specimens were tested, and none —¿P34I —¿P39I of them expressed a detectable level of the antigen recognized —¿P67I by P25.48 and P25.91. In the moderately well-differentiated dP68I —¿ —¿P72I group, 6 of 10 specimens reacted with P25.48, while 5 of 10 *P78I —¿ specimens reacted with P25.91. Two specimens classified as —¿P92I moderately to poorly differentiated prostatic cancers were —¿â€”_———_——__d—— tested and found positive with both P25.48 and P25.91. In the —¿,noreactivity. poorly differentiated to undifferentiated group, 2 of 4 specimens 'When present, normal prostatic epithelium from specimens of prostatic carcinoma was negative. were positive for P25.48, and 3 of 4 specimens were positive ' BPH, benign prostatic hyperplasia. for P25.91. Overall, 9 of 21 specimens reacted with both P25.48 '' Epithelium negative but some glands contained positive secretions. 6940

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Table 5 Reactivity ofP25.48 and P25.91 with prostatic adenocardnomas (by scribed antigens are well expressed by benign prostatic epithe indirect immunoperoxidase assay) lium. These include PAP (1-3), PSA (4, 5), KR-P8 (6, 7), Specimens P2S.48 P25.91 TURP-27 (8), TURP-73 (8), and PSP-94 (11). The antigens WelldifferentiatedModerately —¿â€” recognized by MABs «Pro3 and «ProS (9, 10) are weakly —¿â€” expressed, while those recognized by P6.2 and D83.21 (12, 13) —¿*+ are not expressed by benign prostate epithelium. However, aPro3, aProS, and P6.2 react with the prostate cell line PC-3, differentiatedModeratelywell while D83.21 reacts with the bladder cell line 1-24. In addition, +++—— all these MABs react with epithelium of nonprostatic origin. —¿++ h++hc ++ raíoncogene p21 expression has been found in benign and h++h ++ malignant prostatic tissues, with higher level of expression h*++ associated with increasing grade of tumor (26). Recent studies h+ h + on the immunohistochemical localization of p21n" in human h—h + —¿++ tissues showed that p2lras can be detected in a wide variety of normal fetal and adult tissues, including normal prostatic epi differentiatedPoorlyto poorly ++++ h+ h ++ thelium (27, 28). The antigen recognized by P25.48 and P25.91 is clearly distinct from p21"". or undifferentiatedP32IP83IP85IP90IP93IP10IP30IP35IP36IP53IP54IP87IP91IP97IPlOOIaP25IP44IP46IP50IP65IP86Ia—+— —¿+ MABs P25.48 and P25.91 have a high specificity for prostate ||—+ i, + cancer. The general similarity in their pattern of reactivity ++ suggests that they recognize the same antigen. This is supported * —¿,noreactivity; +, weak reactivity; ++, strong reactivity. * Positive in less than 1% of cells. by our preliminary results from biochemical analysis (data not c h, heterogenous reactivity. shown). About 50% of the cancer specimens expressed the antigens recognized by P25.48 and P25.91, whereas the 17 Table 6 Reactivity ofP25.48 and P25.91 with nonprostatic malignant tissues (by benign prostatic tissues tested were negative. In prostate cancers indirect immunoperoxidase assay) expressing the antigen, the adjacent benign epithelium was Malignant negative, suggesting that antigenic expression is associated with tissuesLungBreastStomachSalivaryKidneyBladderSeminomaRenaltested131132112P25.48P25.91a— malignant transformation of prostatic epithelium. The lack of reactivity of 5 well-differentiated prostatic adenocarcinomas tested and the positive reactivity of 10 of 16 higher grade tumors suggest that the antigen is associated with a more aggressive malignant phenotype. (TCC)MelanomaNo.pelvis MABs P25.48 and P25.91 did not react with normal adults —¿ or fetal tissues, or with malignant tissues of nonprostatic origin. " —¿,noreactivity. The only exception was one specimen of normal breast tissue where a few ducts showed reactivity. However, another normal and P25.91, one specimen reacted with P25.48 only, and one breast tissue specimen and 3 breast cancer specimens showed specimen reacted with P25.91 only. In most positive cases, the no reactivity. In addition, a panel of 46 established cell lines reactivity of these MABs with the tumor was heterogenous, from different origins, including 4 cell lines of prostatic origin, indicating that the antigen recognized by these MABs is ex did not express the antigen recognized by P25.48 and P25.91. pressed by a subpopulation of cells within the tumor. Cell lines of prostatic origin have been found to be very difficult In order to determine if the antigen recognized by P25.48 to establish in long-term tissue culture. Although the origin of and P25.91 is preserved in formalin-fixed, paraffin-embedded the 4 prostatic cell lines has been well characterized (17-19, tissues, we tested tumors that were known to be positive by IIP 29), they may not be representative of the antigenic expression on frozen tissue sections. The reactivity of both MABs was lost of most prostate cancers. This is illustrated by the fact that they when standard IIP procedures were used in formalin-fixed, have little or no expression of PSA and PAP (29), and that paraffin-embedded tissues and could not be unmasked following they do not express other antigens associated with prostate enzymatic digestion with either Pronase, pepsin, or saponin. cancer, such as TURP-27 (8) and PSP-94 (11). Therefore, the Reactivity on Nonprostatic Cancers. Nine types of cancer prostate cancer cell lines currently available may not be optimal tissues of different origins (15 specimens) were tested with candidates for immunization or for screening of MABs directed P25.48 and P25.91 by IIP and were found to be negative (Table at antigens that are relevant to prostate cancer. 6). Because the currently available cell lines lack expression of Reactivity with Established Cancer Cell Lines. A total of 46 the antigen detected by P25.48 and P25.91, fresh specimens of cell lines was tested for expression of the antigen recognized by prostatic cancer remain the only source of antigen to answer P25.48 and P25.91 (Table 7). The MABs were tested by IIP on questions about their biochemical nature, cellular localization, living and fixed cells and by red cell rosetting assays on living and biological functions. cells. None of the cell lines, including the 4 of prostatic origins, If the antigens recognized by P25.48 and P25.91 can be expressed these antigens. detected and measured in the peripheral blood of prostate cancer patients, they might be used for screening and/or mon DISCUSSION itoring of these patients. Although only a subset of the patient Our analysis of the reactivity of P25.48 and P25.91 shows population would have antigen-expressing tumor, theoretically that they recognize an antigen that is different from previously there should be no false elevation of the antigen from benign described prostatic markers (Table 1). Most previously de prostatic hypertrophy as is the case with PSA (30). 6941 Downloaded from cancerres.aacrjournals.org on September 26, 2021. © 1988 American Association for Cancer Research. DEFINITION BY MABs P25.48 AND P25.91 OF A PROSTATE-SPECIFIC ANTIGEN

Table 7 Reactivity O/P25.48 and P25.91 with cultured cancer cell lines Cell lines were tested by indirect immunofluorescence on living and fixed cells and by rosetting assays (rabbit anti-mouse immunoglobulin or Protien A conjugated to human O erythrocytes) on living cells. Tissue Cell typeProstate linesDU-145LNCaPPC-3PC-3 Reactivitylines— type (4)*Breast SK-RC-7—•¿ Renal (9) SK-RC-12— SK-RC-13— LMAIAbBT-20CaMaMCF-7MDA-MB-231SK-BR-7RT-4T-24TCC-SUP253-JHT-29SK-CO-15SW-620RD-2SAOS-2U-20SA-204A-2394TissueSK-RC-24SK-RC-38—

(6)Bladder SK-RC-45— SK-RC-48— SK-RC-Ta— SK-RC-Ha——

SK-LC-1SK-LC-2—Lung (6)

(4)Colon SK-LC-5— SK-LC-6— SK-LC-13SK-LC-1 7—

(3)Sarcoma SK-MG-2— Astrocytoma (5) SK-MG-8— SK-MG-11SK-MG-13SK-MG-1

(5)Cell 5—— EFFRON— MeWo— Melanoma (3) SK-MEL-28Reactivity———————————————__——————— —¿,noreactivity. 11Numbers in parentheses, number.

14. Bates, R. J., Chapman, C. M., Prout, G. R., et al. Immunohistochemical ACKNOWLEDGMENTS identification of prostate acid phosphatase: correlation of tumor grade with acid phosphatase distribution. J. Urol., 127: 574-580, 1982. The authors wish to thank Dr. Hebert Oettgen and Dr. Myron 15. Yam, L. T., J anelala, A. C., Lam, W. K. W., et al. Immunohistochemistry Melamed for their support and Donna Morrisey for her assistance in of prostatic acid phosphatase. Prostate, 2:97-107, 1981. 16. Epstein, J. I., and Eggleston, J. C. Immunohistochemical localization of those studies. prostate-specific acid phosphatase and prostate specific antigen in Stage A2 adenocarcinoma of the prostate: prognostic implications. Hum. Pathol., IS: 853-859, 1984. REFERENCES 17. Kaighn, M. E., Narayan, K. S., Ohnuki, Y., Lechner, J. F., and Jones, L. W. Establishment and characterization of a human prostatic carcinoma cell line 1. Lillehoj, H. S., Choe, B. K., and Rose, N. R. Monoclonal anti-human (PC-3). Invest. Urol., 17: 16-23, 1979. 18. Stone, K. R., Mickey, D. D., Wunderli, H., Mickey, G. H., and Paulson, D. prostatic acid phosphatase antibodies. Mol. Immunol., 19:1199-1202,1982. F. Isolation of a human prostate carcinoma cell line (DU-145). Int. J. Cancer, 2. Nadji, M., and Morales, A. R. Immunohistochemistry of prostatic acid 21:274-281, 1978. phosphatase. Ann. NY Acad. Sci., 390:133-141, 1982. 19. Horoszewicz, J. S., Leong, S. S., Chu, T. M., Friedman, M., Kin, U., Chai, 3. Naritoku, W. Y., and Taylor, C. R. A comparative study of the use of L. S., Kakati, S., Arya, S. K., and Sandberg, A. A. A new model for studies monoclonal antibodies using three different immunohistochemical methods. on human prostatic carcinoma. Proc. Am. Assoc. Cancer Res., 20:212,1979. J. Histochem. Cytochem., 30: 253-260, 1982. 20. Cote, J. R., and Houghton, A. N. The generation of human monoclonal 4. Papsidero, L. D., Croghan, G. A., Wang, M. C., Rumania, M., Johnson, E. antibodies and their use in the analysis of the humoral immune response to A., Valenzuela, L. A., and Chu, T. M. Monoclonal antibody (FS) to human cancer. In: E. G. Engleman (ed.), Human Hybridoma and Monoclonal prostate antigen. Hybridoma, 2: 139-147, 1983. Antibodies, pp. 189-210. New York: Plenum Publishing Corporation, 1985. 5. Frankel, A. E., Rouse, R. V., Wang, M. C., Chu, T. M., and Herzenberg, L. 21. Dippold, W. G., Lloyd, K. O., Li, L. T. C., Ikeda, H., Oettgen, H. F., and A. Monoclonal antibodies to human prostate antigen. Cancer Res., 42:3714- Old, L. J. Cell surface antigens of human malignant melanoma: definition 3718, 1982. of six antigenic systems with mouse monoclonal antibodies. Proc. Nati. Acad. 6. Raynor, R. H., Hazra, T. A., Moncure, C. W., and Mohanakumar, T. Sci. USA, 77:6114-6118, 1980. Characterization of a monoclonal antibody, KR-P8, that detects a new 22. Pfreundschuh, M., Shiku, H., Takahashi, T., Ueda, R., Ransohoff, J., Oett prostate-specific marker. J. Nati. Cancer Inst., 73: 617-625, 1984. gen, H. F., and Old, L. J. Serological analysis of cell surface antigens of 7. Raynor, R. H., Hazra, T. A., Moncure, C. W., and Mohanakumar, T. malignant human brain tumors. Proc. Nati. Acad. Sci. USA, 75:5122-5126, Biochemical nature of the prostate-associated antigen identified by the mono 1978. clonal antibody, KR-P8. Prostate, 9: 21-31, 1986. 23. Cote, R. J., Rosen, P. P., Hakes, T. B., Sedira, M., Bazinet, M., Kinne, D. 8. Starling, J. J., Sieg, S. S., Beckett, M. L., Wirth, P. R., Wahab, Z., Schell W., Old, L. J., and Osborne, M. P. Monoclonal antibodies detect occult hammer, P. F., Ladaga, L. E., Poleskic, S., and Wright, G. L., Jr. Human breast carcinoma métastasesinthe bone marrow of patients with early stage prostate tissue antigens defined by murine monoclonal antibodies. Cancer disease. Am. J. Surg. Pathol., 12: 333-340, 1988. Res., 46: 367-374, 1986. 24. Hoffman, R. A., Kung, P. C., Hansen, W. P., and Goldstein, G. Simple and rapid measurements of human T lymphocytes and their subclasses in periph 9. Ware, J. L., Paulson, D. F., Parks, S. F., and Webb, K. S. Production of eral blood. Proc. Nati. Acad. Sci. USA, 77:4914-4917, 1980. monoclonal antibody aPro3 recognizing a human prostatic carcinoma anti gen. Cancer Res., 42: 1215-1222, 1982. 25. Hoffman, R. A., and Hansen, W. P. Immunofluorescent analysis of blood cells by flow cytometry. Int. J. Immunopharmacol., 3: 249-254, 1981. 10. Webb, K. S., Ware, J. L., Parks, S. F., Briner, W. H., and Paulson, D. F. Monoclonal antibodies to different epitopes on a prostate tumor-associated 26. Viola, M. V., Fromowitz, F., Oravez, S., Deb, S., Finkel, G., Lundy, J., Hand, P., Thor, A., and Schlom, J. Expression of ra.v oncogene p21 in antigen. Cancer Immunol. Immunother., 14:155-166, 1983. prostate cancer. N. Engl. J. Med., 314:133-137, 1986. 11. Dube, J. Y., Frenette, G., Paquin, R., Chapdelaine, P., Tremblay, J., Trem 27. Furth, M. E., Aldrich, T. H., and Cordon-Cardo, C. Expression of ras proto blay, R. R., Lazure, C., Seidah, N., and Chretien, M. Isolation from human oncogene proteins in normal human tissues. Oncogene, 1:47-58, 1987. seminal plasma of an abundant 16-KDa protein originating from the prostate, 28. Garin Chesa, P., Rettig, W. J., Melamed, M. R., Old, L. J., and Niman, H. its identification with a 94-residue peptide originally described as B-inhibin. L. Expression of p21"" in normal and malignant human tissues: lack of J. Androl., 8: 182-189, 1987. association with proliferation and malignancy. Proc. Nati. Acad. Sci. USA, 12. Wright, G. L., Jr., Beckett, M. L., Starling, J. J., Schellhammer, P. F., Sieg, «4:3234-3238,1987. S. M., Ladaga, L. E., and Poleskic, S. Immunohistochemical localization of 29. Webber, M. M. In vitro models for prostate cancer: summary. Prog. Clin. prostate carcinoma-associated antigens. Cancer Res., 43: 5509-5516,1983. Biol. Res., 37:133-147, 1980. 13. Starling, J. J., Beckett, M. L., and Wright, G. L., Jr. Monoclonal antibodies 30. Stamey, T. A., Yang, N., Hay, A. R., McNeal, J. E., Freiha, F. S., and to prostate adenocarcinoma antigens. In: G. L. Wright, Jr. (ed.), Monoclonal Redwine, E. Prostate-specific antigen as a serum marker for adenocarcinoma Antibodies and Cancer, p. 253. New York: Marcel Dekker, Inc., 1984. of the prostate. N. Engl. J. Med., 317: 909-916, 1987. 6942

Downloaded from cancerres.aacrjournals.org on September 26, 2021. © 1988 American Association for Cancer Research. Immunohistochemical Characterization of Two Monoclonal Antibodies, P25.48 and P25.91, Which Define a New Prostate-specific Antigen

Michel Bazinet, Richard J. Cote, Carlos Cordon-Cardo, et al.

Cancer Res 1988;48:6938-6942.

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