### GPR161 Gene Summary

The GPR161 gene encodes an orphan G protein-coupled receptor that plays a crucial role in cellular signaling, particularly in the context of the Sonic Hedgehog (Shh) pathway. Its dysregulation is linked to certain cancers, particularly triple-negative breast cancer. 

#### 1. Associated Genes 
Although the available summaries focused on GPR161's interactions with the Sonic Hedgehog pathway, other genes that could be associated, based on the context of the Shh signaling pathway and ciliary function, include:

- **GLI3**: The transcription factor that GPR161 regulates; GPR161 facilitates the conversion of GLI3 into its repressor form (GLI3R).
- **SHH**: Sonic Hedgehog itself, a key signaling molecule in the pathway.
- **TULP3**: A protein that assists GPR161 in localization to primary cilia.
- **IFT-A complex components**: Critical for ciliary assembly and function, implicating genes that encode proteins in the Intraflagellar Transport (IFT) pathway.

#### 2. Aging and Age-Related Diseases 
While direct associations between GPR161 and aging or age-related diseases are less documented, GPR161’s role in Shh signaling could influence processes related to developmental biology, tissue regeneration, and cancer cell proliferation. Alterations in Shh signaling are noted in various age-related conditions, including:

- **Cancer**: Abnormal activation of Shh signaling is implicated in the progression of tumors and could relate to cancer susceptibility with advancing age.
- **Neurodegenerative diseases**: The role of Shh in neural development and maintenance suggests potential connections to diseases like Alzheimer's or Parkinson's.

#### 3. Drug Interactions 
Currently, there is no direct pharmacological agent known to target GPR161 due to its orphan status (unknown ligand). However, potential drug classes that may indirectly influence GPR161 activity include:

- **Hedgehog pathway inhibitors**: Such as vismodegib or sonidegib, which are used for cancers where the Shh pathway is abnormally activated, may indirectly modulate how GPR161 interacts with Shh signaling.
- **cAMP modulators**: As GPR161 is involved in increasing cAMP levels, drugs that impact cAMP signaling, such as phosphodiesterase inhibitors, might influence GPR161 activity.

#### 4. Pathways and Biological Processes 
GPR161 is primarily involved in:

- **Sonic Hedgehog signaling pathway**: Acts as a negative regulator influencing the processing of the transcription factor GLI3.
- **Ciliary signaling**: GPR161 is localized to primary cilia and is part of the signaling machinery that modulates ciliary function.
- **cAMP signaling pathway**: By increasing cAMP levels, GPR161 influences downstream signaling pathways that include protein kinase A (PKA) dependent mechanisms.
- **Negative regulation of gene expression**: In the context of its role in Shh signaling, it contributes to the repression of GLI transcription factors, impacting the expression of target genes downstream of Shh signaling.

Overall, GPR161 is a significant player in both developmental signaling and tumor biology, making it an important gene for further investigation, particularly in the contexts of cancer treatment and understanding developmental disorders.