Company: SHPH
Filing Date: 2025-02-26
Form Type: 10-K
Source: 0001493152-25-008300
Chunk: 15

Company: Shuttle Pharmaceuticals Holdings, Inc.
Filing Date: 2025-02-26
Form: 10-K
Item: Item 1
Chunk 15
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 small molecule technology delivery
platform which uses HDAC inhibitors, designed to target cancer cells, while protecting healthy tissue.

HDACs
are a class of enzymes that regulate gene expression through chemical modification of histones and non-histone proteins. Increased HDAC
activity leads to a more condensed chromatin (which is a protein complex consisting of DNA and other proteins), decreased gene expression
and loss of key gene products, including tumor suppressor gene function. Inhibition of HDAC activity leads to a more open chromatin and
increased expression of the key gene products. This chromatin modification underlies the epigenetic cellular regulatory system and is
an area of intense investigation.

Our
research and development efforts to date have focused on the discovery of novel, dual functional molecules for potential use in cancer
treatment as radiation sensitizers of cancers, protectors of normal tissues, and activators of the immune responses to antigens expressed
by irradiated cancer cells. To date, we have produced three candidate molecules:

    ●
    SP-1-161,
    a candidate lead of compounds demonstrating activation of the “ATM” gene product (mutated in Ataxia-Telangiectasia).
    Ataxia-Telangiectasia is a human genetic disease characterized by neurological, immunological and radiobiological clinical features.

    ●
    SP-2-225,
    a candidate lead of compounds demonstrating Class II (HDAC6) selective inhibition. HDAC6 is a molecule integral to the presentation
    of antigens by macrophages to T-lymphocytes.

    ●
    SP-1-303
    is a candidate Class I HDAC inhibitor with preferential efficacy against ER positive cancers.

SP-1-161
- A Dual Functional Agent

SP-1-161
is an HDAC inhibitor of the hydroxamate chemical class of compounds and an ATM activator of the indole chemical class. HDACs modify histones
and non-histone proteins, which are key components of the chromatin structure, gene expression regulation, and cell growth. HDAC inhibitors
inhibit cell proliferation, angiogenesis and immunity. Eighteen human HDACs have been identified, subdivided into four classes based
on sequence and functional homology. In cancer cells, HDAC activity silences tumor suppressor genes important for cell growth regulation
and to chromosomal instability. Abnormal HDAC activity is also associated with tumor cell growth, invasion, metastasis and resistance