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Published on: May 4, 2021

LMTK3 is implicated in endocrine resistance via multiple signaling pathways

J Stebbing1, A Filipovic, L C Lit

  • 1Department of Surgery and Cancer, Division of Cancer, Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, UK.

Oncogene
|August 8, 2012
PubMed

Insights

LMTK3 inhibition re-sensitizes tamoxifen-resistant breast cancer to endocrine therapy. High LMTK3 levels predict resistance, while gene amplification in plasma indicates relapse, highlighting LMTK3 as a therapeutic target.

Area of Science:

  • Oncology
  • Molecular Biology
  • Endocrinology

Background:

  • Endocrine therapy resistance is a major challenge in breast cancer treatment.
  • Estrogen receptor-alpha (ERα) is a key target in breast cancer therapy.
  • Identifying novel molecular targets is crucial for overcoming resistance.

Purpose of the Study:

  • To investigate the role of LMTK3 in endocrine resistance in breast cancer.
  • To explore LMTK3 as a potential therapeutic target for overcoming endocrine resistance.

Main Methods:

  • Utilized a tamoxifen-resistant (BT474) xenograft mouse model.
  • Performed whole genome microarray analysis upon LMTK3 silencing.
  • Investigated LMTK3's effect on HSPB8 expression and autophagy in MCF7 cells.
  • Analyzed LMTK3 levels in tumor and plasma samples from patients.

Main Results:

  • LMTK3 inhibition re-sensitized tumors to tamoxifen, reducing tumor volume.
  • LMTK3 silencing modulated genes implicated in tamoxifen resistance, including c-MYC, HSPB8, and SIAH2.
  • LMTK3 upregulates HSPB8, reducing autophagy and protecting cells from tamoxifen-induced death.
  • High baseline LMTK3 in tumors predicted endocrine resistance; acquired LMTK3 gene amplification in plasma correlated with relapse.

Conclusions:

  • LMTK3 plays a significant role in both innate and acquired endocrine resistance in breast cancer.
  • LMTK3 is a potential biomarker for predicting endocrine resistance.
  • Targeting LMTK3 may offer a novel therapeutic strategy to overcome endocrine resistance in breast cancer.

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