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Updated: Aug 9, 2026

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells
06:09

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells

Published on: June 7, 2019

Targeted apoptosis activation with GrB/scFvMEL modulates melanoma growth, metastatic spread, chemosensitivity, and

Yuying Liu1, Weihe Zhang, Ting Niu

  • 1Immunopharmacology and Targeted Therapy Section, Department of Experimental Therapeutics, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA.

Neoplasia (New York, N.Y.)
|April 14, 2006
PubMed

Insights

Human granzyme B (GrB) fused to scFvMEL targets melanoma cells, enhancing chemotherapy and radiation therapy. This targeted fusion protein significantly inhibited tumor growth and metastasis in preclinical models.

Area of Science:

  • Oncology
  • Immunotherapy
  • Molecular Biology

Background:

  • Melanoma poses a significant therapeutic challenge due to its metastatic potential and resistance to conventional treatments.
  • Targeted delivery of cytotoxic agents like human granzyme B (GrB) offers a promising strategy to enhance anti-cancer efficacy.
  • The fusion protein GrB/scFvMEL combines GrB's apoptotic activity with scFvMEL's specificity for the melanoma gp240 antigen.

Purpose of the Study:

  • To evaluate the efficacy of GrB/scFvMEL in combination with chemotherapy and radiation therapy.
  • To assess the effects of GrB/scFvMEL on melanoma cell invasion and metastasis in vitro.
  • To determine the in vivo anti-tumor activity of GrB/scFvMEL against human melanoma xenografts.

Main Methods:

  • In vitro cytotoxicity assays were performed using melanoma cells treated with GrB/scFvMEL alone or in combination with various chemotherapeutic agents.
  • Melanoma cell invasion was assessed using Matrigel invasion assays.
  • In vivo efficacy was evaluated by administering GrB/scFvMEL to nude mice bearing human melanoma A375 xenografts, followed by tumor growth measurement and histological analysis.

Main Results:

  • GrB/scFvMEL demonstrated synergistic cytotoxicity with doxorubicin, vincristine, and cisplatin, and additive effects with etoposide and cytarabine.
  • Pretreatment with GrB/scFvMEL sensitized melanoma cells to ionizing radiation and inhibited their invasion.
  • In vivo, GrB/scFvMEL significantly delayed tumor growth in A375 xenografts and increased apoptotic nuclei in tumor tissues.

Conclusions:

  • GrB/scFvMEL exhibits potent anti-melanoma activity, both as a single agent and in combination with standard therapies.
  • Targeted delivery of GrB via scFvMEL enhances therapeutic outcomes by inducing apoptosis and inhibiting tumor progression.
  • GrB/scFvMEL represents a promising novel therapeutic agent for melanoma treatment, warranting further clinical investigation.

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