The PIK3CD-AS1 gene has been classified as a dubious coding sequence (CDS) and is likely a non-coding RNA, for which there is limited experimental confirmation regarding its biological function. Here’s a more in-depth look at the gene based on your requests.

### 1. Associated Genes
While there may not be extensive literature specifically linking PIK3CD-AS1 to other genes, non-coding RNAs often interact or correlate with others in regulatory networks. Genes that are known to be involved with the phosphoinositide 3-kinase (PI3K) signaling pathway, due to the association implied by the name PIK3CD-AS1, may include:
- **PIK3CD** (phosphoinositide-3-kinase, catalytic delta polypeptide)
- **PTEN** (phosphatase and tensin homolog)
- **AKT1** (AKT serine/threonine kinase 1)
- **MTOR** (mechanistic target of rapamycin)

However, specific associations of PIK3CD-AS1 with other genes remain largely unexplored.

### 2. Aging and Age-Related Diseases
As of now, there is no substantial evidence directly linking PIK3CD-AS1 to aging or age-related diseases in the scientific literature. However, because it is located in close proximity to the PIK3CD gene, which is involved in cellular signaling pathways that regulate vital processes, any roles it may have could potentially influence pathways related to cellular aging or the immune response, given that dysregulation of PI3K signaling is implicated in several age-related conditions. Research linking non-coding RNAs to age-related mechanisms is a growing field, so future evidence could emerge.

### 3. Drug Interactions
Currently, there are no specific drugs or drug classes documented to interact directly with PIK3CD-AS1, as the gene product is still primarily classified as a non-coding RNA, and its functional implications, including pharmacological ones, remain largely unknown. Drugs targeting the PI3K/AKT/mTOR pathway, involving other genes like PIK3CD and MTOR, may indirectly suggest associations, but it would be speculative to assign direct interactions to PIK3CD-AS1 at this stage.

### 4. Pathways and Biological Processes
While specific information directly linking PIK3CD-AS1 to defined pathways is not readily available, it may be implied that:
- If PIK3CD-AS1 plays a role in the regulation of PIK3CD, it may influence signaling pathways such as:
  - **PI3K-AKT signaling pathway**: A crucial pathway involved in cell growth and survival.
  - **mTOR signaling pathway**: This regulates cell metabolism, growth, proliferation, and survival.
- Non-coding RNAs often participate in regulatory mechanisms such as:
  - **Gene expression regulation**: By acting as microRNA sponges or transcriptional regulators.
  - **Cellular stress responses**: Potentially influencing how cells react to external signals.

In summary, PIK3CD-AS1 is an under-characterized non-coding RNA, and while there are interconnections suggested by its name and associations with well-known pathways, more research is needed to clarify its biological roles, associations, implications in aging, drug interactions, and specific pathways it may regulate.