Related Experiment Video

Updated: Aug 8, 2026

Identification of EGFR and RAS Inhibitors using Caenorhabditis elegans
08:12

Identification of EGFR and RAS Inhibitors using Caenorhabditis elegans

Published on: October 5, 2020

[Correlation between inhibitory effect of Manumycin on human hepatoma cancer cell HepG2 and Ras signal transduction

Jun-min Zhou1, Qi-chao Pan, Xiao-ping Yang

  • 1Cancer Institute, Sun Yat-sen University, Guangzhou 510060, P. R. China. zhoujm21@hotmail.com

AI Zheng = Aizheng = Chinese Journal of Cancer
|November 28, 2002
PubMed
Abstract

Insights

Manumycin, a farnesyltransferase inhibitor, significantly inhibited hepatocellular carcinoma HepG2 cell growth. This agent suppressed Ras farnesylation, blocking oncogenic Ras function and potentially serving as a novel anti-cancer therapeutic.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Hepatocellular carcinoma (HCC) treatment remains challenging.
  • Ras pathway activation is crucial in hepatocarcinogenesis.
  • Ras requires farnesylation for activation, making farnesyltransferase a therapeutic target.

Purpose of the Study:

  • To investigate the antitumor effects of Manumycin, a farnesyltransferase inhibitor, on the human hepatoma cell line HepG2.
  • To elucidate Manumycin's impact on the Ras signaling pathway in HCC cells.

Main Methods:

  • Cell growth inhibition was assessed using [3H]thymidine incorporation.
  • Protein expression levels of pan-Ras, N-Ras, ERK1/2, AKT, and MKP-1 were analyzed via Western blot.

Main Results:

  • Manumycin demonstrated significant dose-dependent growth inhibition of HepG2 cells (IC50 = 17.1 ± 2.6 μmol/L).
  • Manumycin inhibited both pan-Ras and N-Ras, with a stronger effect on membrane-bound Ras.
  • Downregulation of phospho-MAPK and phospho-AKT was observed, while total protein levels remained unchanged. MKP-1 expression increased with Manumycin concentration.

Conclusions:

  • Manumycin inhibits HepG2 cell growth by blocking Ras farnesylation and membrane association.
  • The antitumor effect is linked to the inhibition of ERK1/2 and AKT activation and increased MKP-1 expression.
  • Manumycin shows potential as a novel anti-cancer agent for HCC and other human cancers.

More Related Videos

Exploring the Pharmacological Action and Molecular Mechanism of Salidroside in Inhibiting MCF-7 Cell Proliferation and Migration11:13

Exploring the Pharmacological Action and Molecular Mechanism of Salidroside in Inhibiting MCF-7 Cell Proliferation and Migration

Published on: June 9, 2023

Drug-Induced Senescence in Liver Cells Promotes M2 Macrophage Polarization: Implications for Tyrosine Kinase Inhibitor-Associated Hepatotoxicity09:32

Drug-Induced Senescence in Liver Cells Promotes M2 Macrophage Polarization: Implications for Tyrosine Kinase Inhibitor-Associated Hepatotoxicity

Published on: October 17, 2025

Related Concept Videos

Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
The Ras Gene02:38

The Ras Gene

The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a superfamily...
mTOR Signaling and Cancer Progression03:03

mTOR Signaling and Cancer Progression

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...
Interactions Between Signaling Pathways01:19

Interactions Between Signaling Pathways

Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
MAPK Signaling Cascades01:07

MAPK Signaling Cascades

Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
PI3K/mTOR/AKT Signaling Pathway01:22

PI3K/mTOR/AKT Signaling Pathway

The mammalian target of rapamycin  (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1  (mTORC1) and mTOR complex 2  (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast,  mTORC2 consists of a rapamycin-insensitive companion...