### FGFR4 Gene Overview

**Gene Symbol:** FGFR4  
**Chromosomal Location:** Human chromosome 5q12.3  
**Protein Type:** Tyrosine kinase receptor  

#### 1. Associated Genes
The FGFR4 gene has interactions with several other genes and proteins involved in diverse biological processes, including but not limited to:
- **RAS**: Oncogene that, when activated, engages various signaling pathways important for cell growth and differentiation.
- **PIK3R1**: Part of the PI3K pathway, crucial in regulating cell growth, proliferation, and survival.
- **FRS2 (Fibroblast Growth Factor Receptor Substrate 2)**: Adaptor protein involved in FGFR signaling.
- **GRB2 (Growth factor receptor-bound protein 2)**: Adaptor protein that links FGFR4 to activate other signaling proteins.
- **GAB1 (Grb2-associated binder 1)**: Adaptor protein involved in transducing signals from receptor tyrosine kinases.
- **PLC-γ1 (Phospholipase C gamma 1)**: Important enzyme in phosphoinositide signaling pathways.

#### 2. Aging and Age-Related Diseases
FGFR4 has been implicated in various processes that can influence aging and age-related diseases, such as:
- **Cachexia**: Altered FGFR4 signaling has been linked to muscle wasting conditions.
- **Metabolic diseases**: FGFR4’s role in glucose uptake and lipid metabolism suggests a connection to age-related metabolic disorders like type 2 diabetes and obesity.
- **Bone health**: FGFR4 signaling may be involved in regulating bone remodeling, which can decline with age, contributing to osteoporosis.
- **Cancer**: Aberrant FGFR4 signaling has been associated with several types of cancer, which have increased incidence rates with aging, indicating its role in oncogenesis.

#### 3. Drug Interactions
Certain drugs and drug classes have been reported to interact with FGFR4, including:
- **FGFR inhibitors**: Targeted therapies like **FGFR-targeted tyrosine kinase inhibitors**, which block the aberrant signaling of FGFR4 in cancers.
- **Anti-diabetic agents**: Although indirect, drugs affecting metabolic pathways (e.g., Metformin) might influence FGFR4-related signaling pathways involved in glucose metabolism.
  
Additionally, research is ongoing to identify molecules specifically targeting FGFR4, particularly in the context of cancer therapies.

#### 4. Pathways and Biological Processes
FGFR4 is involved in several key pathways and biological processes:
- **Mitogen-Activated Protein Kinase (MAPK) signaling pathway**: Promotes cell division, survival, and differentiation.
- **Phosphatidylinositol-3-kinase (PI3K) signaling pathway**: Critical for cell growth and survival signaling.
- **FGF signaling**: Plays a pivotal role in numerous processes, including embryonic development and tissue repair.
- **Calcium signaling**: Influences processes involving cell proliferation and differentiation.
- **Lipid metabolism and glucose homeostasis**: Influences various metabolic pathways, especially related to energy balance and metabolic syndrome.

Overall, FGFR4 represents a critical node in cellular signaling networks affecting development, metabolism, and potentially aging and age-related diseases. Further investigation into FGFR4 and its signaling pathways may yield new therapeutic strategies for conditions where these processes are disrupted.