Characterizing ALCAM as an Oncoprotein and Immunotherapeutic Target in Neuroblastoma Jarrett Matthew Lindsay

Format:

• Book
• Thesis/Dissertation

Author/Creator:

• Lindsay, Jarrett Matthew, author.

Contributor:

• University of Pennsylvania. Pharmacology., degree granting institution.

Language:

English

Subjects (All):

• Pharmacology.
• Biology.
• Cellular biology.
• Pediatrics.
• Immunology.
• 0419.
• 0306.
• 0379.
• 0982.
• 0767.

Local Subjects:

• Pharmacology.
• Biology.
• Cellular biology.
• Pediatrics.
• Immunology.
• 0419.
• 0306.
• 0379.
• 0982.
• 0767.

Physical Description:

1 electronic resource (160 pages)

Contained In:

Dissertations Abstracts International 86-07B

Place of Publication:

Ann Arbor : ProQuest Dissertations and Theses, 2024

Language Note:

English

Summary:

Neuroblastoma is the most common extracranial solid malignancy in children. Half of children diagnosed with neuroblastoma are considered high-risk for relapse based on clinical and tumor biological features of their tumors, and only half of high-risk patients will survive five years. Although monoclonal antibodies targeting the disialoganglioside GD2 have extended survival in neuroblastoma, relapse remains common. Thus, there remains a critical need for discovery of new immunotherapeutic targets. ALCAM is a cell-surface cell adhesion protein that is more highly expressed in neuroblastoma than a majority of human cancers. Previous studies have implicated ALCAM overexpression in adult cancer growth and metastasis, but ALCAM expression in normal tissue has impeded therapeutic development. The overall aim of this dissertation was to credential ALCAM as an immunotherapy target, which we addressed with three specific aims: (1) elucidating the role of ALCAM in neuroblastoma growth and survival; (2) determining the mechanism of ALCAM expression; (3) exploiting these findings with a novel antibody-drug conjugate platform to avoid on-target, off-tumor toxicities. We generated inducible ALCAM knockdown cell lines using CRISPR inhibition and profiled the effects on neuroblastoma growth and survival using live-cell monitoring assays, immunoblotting, and flow cytometry. ALCAM depletion significantly impaired cell growth and promoted apoptosis in all cell lines tested, which comprised a variety of known oncogenic aberrations. Chromatin Immunoprecipitation (ChIP)-sequencing data for the oncoprotein MYCN showed binding of MYCN to the ALCAM promoter. We used Promoter Capture-C data and discovered a region approximately 10 kb upstream of the ALCAM promoter that was predicted to be an enhancer. Using luciferase reporter vectors and the MYC(N)-MAX dimerization inhibitor MYCi975, we showed that MYCN drives ALCAM expression. We also validated the activity of the upstream ALCAM enhancer region and uncovered a critical AP-1 binding motif therein. Finally, we showed promising pre-clinical efficacy in subcutaneously engrafted, neuroblastoma-bearing mice of a conditionally activated, ALCAM-targeting antibody-drug conjugate, using PROBODY® Antibody-Drug Conjugate (PDC) technology, which leverages masking peptides that reduce antigen binding in normal tissue. Together, these data credential ALCAM as a viable immunotherapeutic target in neuroblastoma

Notes:

• Source: Dissertations Abstracts International, Volume: 86-07, Section: B.
• Advisors: Maris, John M. Committee members: Chou, Margaret; Ryeom, Sandra; Grohar, Patrick; Tsourkas, Andrew
• Ph.D. University of Pennsylvania 2024

Local Notes:

School code: 0175

ISBN:

9798302183026

Access Restriction:

Restricted for use by site license