aibioGenprex reports mouse research linking TUSC2 to healthy brain aging
Tickers GNPX
A peer-reviewed mouse study tied the TUSC2 gene, used in Genprex's REQORSA program, to protein balance and synaptic function in the hippocampus.
Key facts
- Company
- Genprex, Inc. (NASDAQ: GNPX)
- News type
- Company Updates
- Primary source
- Genprex, Inc. 8-K (2026-10-21)
Genprex, Inc. (Nasdaq: GNPX) said on October 21, 2026 that new peer-reviewed research in mice points to a role for the TUSC2 tumor suppressor gene in healthy brain aging. The company disclosed the findings in a Form 8-K filed the same day. The study, titled "Mitochondrial calcium sensor TUSC2 protects the aging hippocampus from proteostasis collapse in a sex-specific manner," was published in Mechanisms of Ageing and Development by researchers at Meharry Medical College.
What the mouse study found
TUSC2 is the therapeutic gene used in Genprex's investigational REQORSA gene therapy, which is being developed for the treatment of cancer. According to the filing, loss of TUSC2 in mice was associated with substantial disruption of mitochondrial function, protein homeostasis and pathways involved in neuronal communication within the hippocampus. These effects were markedly more pronounced in male mice than in females. Female mice showed adaptive cellular stress responses, which the filing says suggests greater resilience to TUSC2 deficiency. In males, TUSC2 deficiency was associated with impaired protein quality-control pathways and a significant increase in protein aggregate size in the hippocampus.
The researchers also analyzed existing human gene-expression datasets. They found that TUSC2 expression declined significantly with age in 11 of 13 examined brain regions, with additional reductions observed in Alzheimer's disease datasets. TUSC2 protein levels in the hippocampus, as in the rest of the brain, decrease as humans age.
Genprex was careful about the limits of the work. The filing states that the research did not evaluate REQORSA as a treatment for aging or neurodegenerative disease, and it describes the findings as exploratory. The mice carried an engineered TUSC2 knockout, which the company says establishes that model as a tool for studying early mitochondrial dysfunction, impaired protein homeostasis and age-related changes in brain function.
The lead program and its finances
The 10-K business section says REQORSA is being studied in several lung cancer trials. The Acclaim-1 trial combines REQORSA with AstraZeneca's Tagrisso (osimertinib) in late-stage non-small cell lung cancer with activating EGFR mutations that progressed on Tagrisso or Tagrisso-containing regimens. The recommended Phase 2 dose is 0.12 mg/kg every 21 days. Three of the twelve patients originally enrolled in the Phase 1 dose escalation portion had prolonged progression-free survival. One patient reached a partial remission after the second course and has maintained it through 60 courses of treatment, approximately 42 months. The other two of those three later progressed, after about 24 and 10 months, and the sources give no response data for the other nine patients. The company also stopped enrolling its Acclaim-2 trial with Keytruda in 2024, citing enrollment challenges and delays.
The Phase 2a expansion portion is expected to enroll approximately 33 patients, with an interim analysis after 19 patients. The company expects that interim analysis in the second half of 2026. The Food and Drug Administration has granted Fast Track Designation for the Acclaim-1 combination.
For the fiscal year ended December 31, 2025, the XBRL data show research and development expense of $9.4 million and a net loss of $16.2 million. For 2024, the comparable figures were $10.5 million and $21.1 million. Cash from operations was negative $15.3 million in 2025 and negative $17.9 million in 2024. Year-end cash and cash equivalents were $7.8 million for 2025, according to a 10-Q filed August 14, 2026, compared with $1.6 million at the end of 2024. The data also give cash and cash equivalents of $15.2 million at June 30, 2026.
What comes next
The company said the findings suggest TUSC2 may play a foundational role in brain health, and that restoring TUSC2 may open new avenues for therapeutic intervention in age-related cognitive disorders. The release described this as exploratory work that adds to the understanding of TUSC2 beyond its established role in cancer. The evidence is from engineered knockout mice plus a comparison with existing human datasets, so it shows an association, not that restoring TUSC2 helps any patient. The company's actual path to approval runs through lung cancer, where the Acclaim-1 interim analysis is still pending. Net loss was $16.2 million for 2025, and the filing gives no timeline for further TUSC2 research.