Immunoconjugates of geldanamycin and anti-HER2 monoclonal antibodies

Antiproliferative activity on human breast carcinoma cell lines

Raya Mandler, Chuanchu Wu, Edward A. Sausville, Alexis J. Roettinger, David J. Newman, David K. Ho, C. Richter King, Dajun Yang, Marc E. Lippman, Nicholas F. Landolfi, Ekaterina Dadachova, Martin W. Brechbiel, Thomas A. Waldmann

Research output: Contribution to journalArticle

51 Citations (Scopus)

Abstract

Background: HER2 is a membrane receptor whose overexpression is strongly associated with poor prognosis in breast carcinomas. Inhibition of HER2 activity can reduce tumor growth, which led to the development of Herceptin, an anti-HER2 monoclonal antibody (MAb) that is already in clinical use. However, the objective response rate to Herceptin monotherapy is quite low. HER2 activity can also be inhibited by the highly cytotoxic antibiotic geldanamycin (GA). However, GA is not used clinically because of its adverse toxicity. Our purpose was to enhance the inhibitory activity of anti-HER2 MAb by coupling it to GA. Methods: We synthesized 17-(3-aminopropylamino)GA (17-APA-GA) and conjugated it to the anti-HER2 MAb e21, to form e21: GA. The noninternalizing anti-HER2 MAb AE1 was used as a control. Internalization assays and western blot analyses were used to determine whether the anti-HER2 MAbs and their immunoconjugates were internalized into HER2-expressing cells and reduced HER2 levels. All statistical tests were two-sided. Results: The immunoconjugate e21: GA inhibited the proliferation of HER2-overexpressing cell lines better than unconjugated e21 (concentration required for 50% inhibition = 40 versus 1650 μg/mL, respectively). At 15 μg/mL, e21:GA reduced HER2 levels by 86% within 16 hours, whereas unconjugated e21, 17-APA-GA, or AE1: GA reduced HER2 levels by only 20%. These effects were not caused by release of 17-APA-GA from the immunoconjugate because immunoconjugates containing [3H]GA were stable in serum at 37°C. Furthermore, e21:GA did not significantly inhibit proliferation of the adult T-cell leukemia cell line HuT102, which is HER2 negative yet highly sensitive to GA. Conclusions: Our findings suggest that conjugating GA to internalizing MAbs enhances the inhibitory effect of the MAbs. This approach might also be applied in cellular targeting via growth factors and may be of clinical interest.

Original languageEnglish (US)
Pages (from-to)1573-1581
Number of pages9
JournalJournal of the National Cancer Institute
Volume92
Issue number19
StatePublished - Oct 4 2000
Externally publishedYes

Fingerprint

Immunoconjugates
Human Activities
Monoclonal Antibodies
Breast Neoplasms
Cell Line
geldanamycin
Antineoplastic Antibiotics
Adult T Cell Leukemia Lymphoma

ASJC Scopus subject areas

  • Cancer Research
  • Oncology

Cite this

Mandler, R., Wu, C., Sausville, E. A., Roettinger, A. J., Newman, D. J., Ho, D. K., ... Waldmann, T. A. (2000). Immunoconjugates of geldanamycin and anti-HER2 monoclonal antibodies: Antiproliferative activity on human breast carcinoma cell lines. Journal of the National Cancer Institute, 92(19), 1573-1581.

Immunoconjugates of geldanamycin and anti-HER2 monoclonal antibodies : Antiproliferative activity on human breast carcinoma cell lines. / Mandler, Raya; Wu, Chuanchu; Sausville, Edward A.; Roettinger, Alexis J.; Newman, David J.; Ho, David K.; King, C. Richter; Yang, Dajun; Lippman, Marc E.; Landolfi, Nicholas F.; Dadachova, Ekaterina; Brechbiel, Martin W.; Waldmann, Thomas A.

In: Journal of the National Cancer Institute, Vol. 92, No. 19, 04.10.2000, p. 1573-1581.

Research output: Contribution to journalArticle

Mandler, R, Wu, C, Sausville, EA, Roettinger, AJ, Newman, DJ, Ho, DK, King, CR, Yang, D, Lippman, ME, Landolfi, NF, Dadachova, E, Brechbiel, MW & Waldmann, TA 2000, 'Immunoconjugates of geldanamycin and anti-HER2 monoclonal antibodies: Antiproliferative activity on human breast carcinoma cell lines', Journal of the National Cancer Institute, vol. 92, no. 19, pp. 1573-1581.
Mandler, Raya ; Wu, Chuanchu ; Sausville, Edward A. ; Roettinger, Alexis J. ; Newman, David J. ; Ho, David K. ; King, C. Richter ; Yang, Dajun ; Lippman, Marc E. ; Landolfi, Nicholas F. ; Dadachova, Ekaterina ; Brechbiel, Martin W. ; Waldmann, Thomas A. / Immunoconjugates of geldanamycin and anti-HER2 monoclonal antibodies : Antiproliferative activity on human breast carcinoma cell lines. In: Journal of the National Cancer Institute. 2000 ; Vol. 92, No. 19. pp. 1573-1581.
@article{365d14d7f170482b941c00bfbf94e306,
title = "Immunoconjugates of geldanamycin and anti-HER2 monoclonal antibodies: Antiproliferative activity on human breast carcinoma cell lines",
abstract = "Background: HER2 is a membrane receptor whose overexpression is strongly associated with poor prognosis in breast carcinomas. Inhibition of HER2 activity can reduce tumor growth, which led to the development of Herceptin, an anti-HER2 monoclonal antibody (MAb) that is already in clinical use. However, the objective response rate to Herceptin monotherapy is quite low. HER2 activity can also be inhibited by the highly cytotoxic antibiotic geldanamycin (GA). However, GA is not used clinically because of its adverse toxicity. Our purpose was to enhance the inhibitory activity of anti-HER2 MAb by coupling it to GA. Methods: We synthesized 17-(3-aminopropylamino)GA (17-APA-GA) and conjugated it to the anti-HER2 MAb e21, to form e21: GA. The noninternalizing anti-HER2 MAb AE1 was used as a control. Internalization assays and western blot analyses were used to determine whether the anti-HER2 MAbs and their immunoconjugates were internalized into HER2-expressing cells and reduced HER2 levels. All statistical tests were two-sided. Results: The immunoconjugate e21: GA inhibited the proliferation of HER2-overexpressing cell lines better than unconjugated e21 (concentration required for 50{\%} inhibition = 40 versus 1650 μg/mL, respectively). At 15 μg/mL, e21:GA reduced HER2 levels by 86{\%} within 16 hours, whereas unconjugated e21, 17-APA-GA, or AE1: GA reduced HER2 levels by only 20{\%}. These effects were not caused by release of 17-APA-GA from the immunoconjugate because immunoconjugates containing [3H]GA were stable in serum at 37°C. Furthermore, e21:GA did not significantly inhibit proliferation of the adult T-cell leukemia cell line HuT102, which is HER2 negative yet highly sensitive to GA. Conclusions: Our findings suggest that conjugating GA to internalizing MAbs enhances the inhibitory effect of the MAbs. This approach might also be applied in cellular targeting via growth factors and may be of clinical interest.",
author = "Raya Mandler and Chuanchu Wu and Sausville, {Edward A.} and Roettinger, {Alexis J.} and Newman, {David J.} and Ho, {David K.} and King, {C. Richter} and Dajun Yang and Lippman, {Marc E.} and Landolfi, {Nicholas F.} and Ekaterina Dadachova and Brechbiel, {Martin W.} and Waldmann, {Thomas A.}",
year = "2000",
month = "10",
day = "4",
language = "English (US)",
volume = "92",
pages = "1573--1581",
journal = "Journal of the National Cancer Institute",
issn = "0027-8874",
publisher = "Oxford University Press",
number = "19",

}

TY - JOUR

T1 - Immunoconjugates of geldanamycin and anti-HER2 monoclonal antibodies

T2 - Antiproliferative activity on human breast carcinoma cell lines

AU - Mandler, Raya

AU - Wu, Chuanchu

AU - Sausville, Edward A.

AU - Roettinger, Alexis J.

AU - Newman, David J.

AU - Ho, David K.

AU - King, C. Richter

AU - Yang, Dajun

AU - Lippman, Marc E.

AU - Landolfi, Nicholas F.

AU - Dadachova, Ekaterina

AU - Brechbiel, Martin W.

AU - Waldmann, Thomas A.

PY - 2000/10/4

Y1 - 2000/10/4

N2 - Background: HER2 is a membrane receptor whose overexpression is strongly associated with poor prognosis in breast carcinomas. Inhibition of HER2 activity can reduce tumor growth, which led to the development of Herceptin, an anti-HER2 monoclonal antibody (MAb) that is already in clinical use. However, the objective response rate to Herceptin monotherapy is quite low. HER2 activity can also be inhibited by the highly cytotoxic antibiotic geldanamycin (GA). However, GA is not used clinically because of its adverse toxicity. Our purpose was to enhance the inhibitory activity of anti-HER2 MAb by coupling it to GA. Methods: We synthesized 17-(3-aminopropylamino)GA (17-APA-GA) and conjugated it to the anti-HER2 MAb e21, to form e21: GA. The noninternalizing anti-HER2 MAb AE1 was used as a control. Internalization assays and western blot analyses were used to determine whether the anti-HER2 MAbs and their immunoconjugates were internalized into HER2-expressing cells and reduced HER2 levels. All statistical tests were two-sided. Results: The immunoconjugate e21: GA inhibited the proliferation of HER2-overexpressing cell lines better than unconjugated e21 (concentration required for 50% inhibition = 40 versus 1650 μg/mL, respectively). At 15 μg/mL, e21:GA reduced HER2 levels by 86% within 16 hours, whereas unconjugated e21, 17-APA-GA, or AE1: GA reduced HER2 levels by only 20%. These effects were not caused by release of 17-APA-GA from the immunoconjugate because immunoconjugates containing [3H]GA were stable in serum at 37°C. Furthermore, e21:GA did not significantly inhibit proliferation of the adult T-cell leukemia cell line HuT102, which is HER2 negative yet highly sensitive to GA. Conclusions: Our findings suggest that conjugating GA to internalizing MAbs enhances the inhibitory effect of the MAbs. This approach might also be applied in cellular targeting via growth factors and may be of clinical interest.

AB - Background: HER2 is a membrane receptor whose overexpression is strongly associated with poor prognosis in breast carcinomas. Inhibition of HER2 activity can reduce tumor growth, which led to the development of Herceptin, an anti-HER2 monoclonal antibody (MAb) that is already in clinical use. However, the objective response rate to Herceptin monotherapy is quite low. HER2 activity can also be inhibited by the highly cytotoxic antibiotic geldanamycin (GA). However, GA is not used clinically because of its adverse toxicity. Our purpose was to enhance the inhibitory activity of anti-HER2 MAb by coupling it to GA. Methods: We synthesized 17-(3-aminopropylamino)GA (17-APA-GA) and conjugated it to the anti-HER2 MAb e21, to form e21: GA. The noninternalizing anti-HER2 MAb AE1 was used as a control. Internalization assays and western blot analyses were used to determine whether the anti-HER2 MAbs and their immunoconjugates were internalized into HER2-expressing cells and reduced HER2 levels. All statistical tests were two-sided. Results: The immunoconjugate e21: GA inhibited the proliferation of HER2-overexpressing cell lines better than unconjugated e21 (concentration required for 50% inhibition = 40 versus 1650 μg/mL, respectively). At 15 μg/mL, e21:GA reduced HER2 levels by 86% within 16 hours, whereas unconjugated e21, 17-APA-GA, or AE1: GA reduced HER2 levels by only 20%. These effects were not caused by release of 17-APA-GA from the immunoconjugate because immunoconjugates containing [3H]GA were stable in serum at 37°C. Furthermore, e21:GA did not significantly inhibit proliferation of the adult T-cell leukemia cell line HuT102, which is HER2 negative yet highly sensitive to GA. Conclusions: Our findings suggest that conjugating GA to internalizing MAbs enhances the inhibitory effect of the MAbs. This approach might also be applied in cellular targeting via growth factors and may be of clinical interest.

UR - http://www.scopus.com/inward/record.url?scp=0034605438&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034605438&partnerID=8YFLogxK

M3 - Article

VL - 92

SP - 1573

EP - 1581

JO - Journal of the National Cancer Institute

JF - Journal of the National Cancer Institute

SN - 0027-8874

IS - 19

ER -