Cauloside A interacts with TLR4 to induce JNK/Caspase-3/GSDME-dependent pyroptosis in non-small cell lung cancer

Qin-Qin Wang1, Wentong Zhao2, Lina Liu3

  • 1College of Pharmacy, Jiangxi University of Chinese Medicine, Nanchang, 330004, China; Guangxi Engineering Technology Research Center of Advantage Chinese Patent Drug and Ethnic Drug Development, Nanning, 530200, China.

Insights

Cauloside A, a natural compound, effectively inhibits non-small cell lung cancer (NSCLC) growth by activating a novel pyroptotic pathway through TLR4 interaction. This discovery offers a promising new therapeutic strategy for NSCLC treatment.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Non-small cell lung cancer (NSCLC) is a leading cause of cancer death globally.
  • Current NSCLC treatments face limitations due to drug resistance and side effects.
  • Novel therapeutic agents are urgently needed for effective NSCLC management.

Purpose of the Study:

  • To elucidate the anti-tumor mechanism of Cauloside A in NSCLC.
  • To investigate Cauloside A's interaction with Toll-like receptor 4 (TLR4).
  • To explore Cauloside A's potential as a therapeutic agent for NSCLC.

Main Methods:

  • Cell viability assays (LDH release), transmission electron microscopy, and Annexin V/7-AAD staining were used in NSCLC cell lines (A549, H1299).
  • Mechanistic studies involved Western blotting for JNK phosphorylation, caspase-3 activation, and GSDME cleavage.
  • Target identification utilized cellular thermal shift assays, surface plasmon resonance, and molecular docking.
  • In vivo efficacy was assessed in a C57BL/6 mouse syngeneic model, evaluating tumor growth, Ki67, and PCNA expression.

Main Results:

  • Cauloside A dose-dependently reduced NSCLC cell viability and induced pyroptosis.
  • Cauloside A activated GSDME cleavage via JNK phosphorylation and caspase-3 activation, independent of GSDMD.
  • TLR4 was identified as a direct binding target of Cauloside A.
  • In vivo, Cauloside A suppressed tumor growth without toxicity, activating the TLR4-JNK-caspase-3-GSDME pathway in tumor tissues.

Conclusions:

  • Cauloside A acts as a TLR4 modulator, initiating GSDME-dependent pyroptosis in NSCLC.
  • This study reveals a novel pyroptotic pathway activated by Cauloside A.
  • Cauloside A demonstrates significant potential as a therapeutic strategy for NSCLC.

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