Evaluation of the efficacy of ADC in vitro and in vivo

Abstract
Antibody drug conjugate (ADC) is a promising complex with therapeutic potential that aimed to the treatment of solid tumor and hematological malignancies. Compared with the therapeutic monoclonal antibody, ADCs-derived monoclonal antibody is conjugated with cytotoxic agents which can deliver potent cellular toxins to targeted cancer cells specifically. According to the specialization of ADCs, we have established the state-of-the-art platform to support the evaluation of the efficacy of ADC or the combination strategy of ADC and other anti-cancer therapy in the process of pre-clinical drug discovery, such as target validation, efficient internalization, cytotoxic effects and in vivo efficacy testing.
In order to explore the mechanism of action and the functional effects of ADC for supporting the application of investigational new drug. Our flow cytometry platform (BD LSRFortessa X20) supports to evaluate the target validation and the process of internalization in a quick, reliable and reproducible way. Also we are able to construct customized antigen-specific overexpression or KI cells used for the development of ADCs which target on the specific antigens theoretically. In terms of in vivo ADCs assessment, our abundant CDX and PDX resource facilitates the process of in vivo ADCs evaluation, and we have already assess the efficacy of ADC or the combination treatment of ADC and other anti-tumor drugs in several animal models.

Methods

Fig 1. Methods for the evaluation of the efficacy of ADC in vitro and in vivo

Results

Fig 2. In vitro Target and affinity validation by flow cytometry
Trastuzumab and T-DM1 have higher binding affinity to SK-OV-3 and SK-BR-3 cell lines than MDA-MB-231 cell line. SK-OV-3 and SK-BR-3 have higher HER2 level than MDA-MB- 231.

Fig 3. In vitro T-DM1 internalization assay in SK-BR-3 and MDA-MB-231 cells The internalization signal of T-DM1 is increased in SK-BR-3 cells (HER2+), while there is no change in MDA-MB-231 cells (HER2-).

Fig 4. In vitro cell viability and ADCC assays in SK-BR-3 cells
A. T-DM1 displays the anti-proliferation effect on SK-BR-3 cells in vitro. B. T-DM1 and

Trastuzumab stimulate the antibody dependent cellular cytotoxicity of NK cells on SK-BR-3 cells.

Fig 5. In vitro cell cycle assay on SK-BR-3 and MDA-MB-231
T-DM1 displays the effect to impact the cell cycle of SK-BR-3 (HER2+) at 24 and 48 hours, but no effect on MDA-MB-231 (HER2-) at the same time points.

Fig 6. In vivo efficacy study of SK-OV-3 (CDX) and ST-02-0077 (PDX) models T-DM1 shows anti-tumor efficacy in both SK-OV-3 (CDX) and ST-02-0077 (PDX) models.

Summary

• We have successfully established a series of in vitro assays and in vivo models to study the function and mechanism of action of ADC.

• In these assays or models, we also validated the efficacy of other drugs in the same or different mechanism.

Reference

  • Peipei Liu, Jiajun Fan, Ziyu Wang, Wenjing Zai, Ping Song, Yongping Li and Dianwen Ju. The role of autophagy in the cytotoxicity induced by tratuzumab emtansine (T-DM1) in HER2- positive breast cancer cells. AMB Express, (2020) 10:107.
  • Roberta Nicoletti, Salvatore Lopez, Stefania Bellone, Emiliano Cocco, et al. T-DM1, a novel antibody-drug conjugate, is highly effective against uterine and ovarian carcinosarcomas overexpressing HER2. Clin Exp Metastasis, 2015 Janunary, 32(1):29-38.
  • John M. Lambert, Ravi V. Chari. Ado-tratuzumab Ematansine (T-DM1): An antibody-drug conjugate (ADC) for HER2-positive breast cancer. J. Med. Chem. 2014, 57:6949-6964.
  • Mark Barok, Minna Tanner, Katri Koninki, Jorma Isola. Trastuzumab-DM1 causes tumor growth inhibition by mitotic catastrophe in trastuzumab-resistant breast cancer cells in vivo. Breast Cancer research, 2011, 13:R46.


10 ADC_5566_Jun Huang

Download

← Return to Resources