Related Experiment Video

Updated: May 17, 2026

Osteoclast Derivation from Mouse Bone Marrow
06:17

Osteoclast Derivation from Mouse Bone Marrow

Published on: November 6, 2014

p38 MAPK in myeloma cells regulates osteoclast and osteoblast activity and induces bone destruction

Jin He1, Zhiqiang Liu, Yuhuan Zheng

  • 1Department of Lymphoma/Myeloma, Division of Cancer Medicine and Center for Cancer Immunology Research, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA.

Cancer Research
|October 16, 2012
PubMed

Insights

p38 mitogen-activated protein kinase (MAPK) signaling in myeloma drives bone destruction by inhibiting bone formation and promoting bone breakdown. Targeting p38 may treat myeloma-related bone lesions.

Area of Science:

  • Oncology
  • Molecular Biology
  • Bone Biology

Background:

  • p38 mitogen-activated protein kinase (MAPK) is active in human myeloma and linked to bone destruction.
  • The precise mechanisms by which p38 MAPK contributes to myeloma-induced bone pathology are not fully understood.

Purpose of the Study:

  • To elucidate the molecular mechanisms by which p38 MAPK signaling in myeloma cells regulates bone destruction.
  • To investigate the roles of DKK-1 and MCP-1 in p38-mediated bone pathology.
  • To evaluate the therapeutic potential of targeting p38, DKK-1, or MCP-1 for treating osteolytic bone lesions.

Main Methods:

  • Investigated the effects of p38 activity on osteoblast and osteoclast differentiation and function in myeloma.
  • Analyzed the regulation of DKK-1 and MCP-1 expression and secretion by p38.
  • Assessed the impact of inhibiting p38, DKK-1, or MCP-1 on bone lesions in vivo.
  • Examined the effects of DKK-1 and MCP-1 on osteoclast differentiation and RANK/RANKL expression.

Main Results:

  • p38 MAPK activity in myeloma inhibits osteoblast differentiation and bone formation.
  • p38 MAPK enhances osteoclast maturation and bone resorption by regulating DKK-1 and MCP-1.
  • DKK-1 and MCP-1 promote osteoclast differentiation by upregulating RANK and RANKL.
  • Inhibition of p38, DKK-1, or MCP-1 reduced bone lesions in vivo.

Conclusions:

  • p38 signaling in myeloma cells orchestrates osteoblast suppression and osteoclast activation, leading to bone destruction.
  • DKK-1 and MCP-1 are key mediators of p38's pro-resorptive effects.
  • Targeting p38 MAPK presents a promising therapeutic strategy for managing osteolytic bone lesions in myeloma and potentially other cancers.

More Related Videos

A Simple Pit Assay Protocol to Visualize and Quantify Osteoclastic Resorption In Vitro07:03

A Simple Pit Assay Protocol to Visualize and Quantify Osteoclastic Resorption In Vitro

Published on: June 16, 2022

Related Concept Videos

Osteoclasts in Bone Remodeling01:31

Osteoclasts in Bone Remodeling

Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during bone...
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...
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...
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...
The Intrinsic Apoptotic Pathway01:31

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
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...