Independent Researchers Find Genprex’s TUSC2 May Be a Novel Target and Biomarker for Thyroid Cancer Therapy

Source:  Genprex, Inc. 1/29/2020

• Study results show TUSC2 overexpression decreased thyroid cancer tumor metastasis and increased sensitivity to apoptosis by increasing SMAC/DIABLO and Cytochrome C protein levels
• Study highlights the possibility that TUSC2 may also be effective in thyroid cancer therapy and adds to the growing body of research on TUSC2 beyond the non-small cell lung cancer indication the Company is initially pursuing
• TUSC2 is the active agent in the Company’s Oncoprex™ immunogene therapy

Genprex, Inc. (“Genprex” or the “Company”) (NASDAQ: GNPX), a clinical-stage gene therapy company utilizing a unique, non-viral proprietary platform designed to deliver tumor suppressor genes to cancer cells, announced that independent researchers reported in a recent study that TUSC2, a tumor suppressor gene and the active agent in Genprex’s Oncoprex™ immunogene therapy, is a potential target and biomarker for thyroid carcinoma. Genprex has no affiliation with these researchers.

Published in the International Journal of Molecular Sciences, the study reports that TUSC2 overexpression decreased thyroid cancer proliferation, migration and invasion. Cell proliferation, migration and invasion ability are essential steps in tumor metastasis. TUSC2 forced expression reduced thyroid cancer cell proliferation and could represent an important tool to arrest cancer cell proliferation, while TUSC2 restoration decreased the migration and invasion of thyroid cancer cell lines. 

The study also found that TUSC2 increased sensitivity to apoptosis by increasing the SMAC/DIABLO and Cytochrome C proteins, which play major roles in apoptosis. TUSC2 forced expression increased these protein levels, and, inversely, the silencing of TUSC2 induced resistance to apoptosis.

Based on the results of the study, researchers concluded that TUSC2 is negatively associated with thyroid cancer aggressiveness and, thus could be a novel target and biomarker for thyroid cancer therapy.

“We continue to be encouraged by data resulting from studies conducted at multiple research institutions suggesting that TUSC2 may be an effective treatment for many types of cancer, now including thyroid cancer,” said Rodney Varner, Genprex’s Chairman and Chief Executive Officer.

The authors further state that thyroid carcinoma is the most common endocrine cancer and includes many different forms. Anaplastic thyroid carcinoma (ATC) is the rarest but most lethal subtype. ATC patients usually present a rapidly enlarging neck mass, a high rate of distant metastases and approximately 95 percent mortality at six months. Conversely, papillary thyroid carcinoma (PTC), the most common type of thyroid cancer, is generally characterized by good outcomes, as it is highly curable by surgery and radioiodine therapy. However, some PTC patients have an aggressive disease and can develop distant metastasis.

The same researchers have previously reported that TUSC2 is downregulated in almost all ATC samples and in the vast majority of PTC samples, suggesting TUSC2’s important role in thyroid cancer progression. In 2019, an estimated 50,000 patients in the U.S. were diagnosed with thyroid cancer.

Genprex is conducting clinical and pre-clinical research to evaluate the effectiveness of TUSC2 when combined with targeted therapies and immunotherapies for non-small cell lung cancer. Existing pre-clinical data also suggest that TUSC2 may be effective against breast cancer, glioblastoma, head and neck cancer, kidney cancer, and soft tissue sarcomas. This new independent study raises the possibility that TUSC2 may also be used to treat thyroid cancer.

About Genprex, Inc.
Genprex, Inc. is a clinical-stage gene therapy company developing potentially life-changing technologies for cancer patients based upon a unique proprietary technology platform. Genprex’s platform technologies are designed to administer cancer-fighting genes by encapsulating them into nanoscale hollow spheres called nanovesicles, which are then administered intravenously and taken up by tumor cells where they express proteins that are missing or found in low quantities. The company’s lead product candidate, Oncoprex™ immunogene therapy for non-small cell lung cancer (NSCLC), has a multimodal mechanism of action whereby it has been shown to interrupt cell signaling pathways that cause replication and proliferation of cancer cells, re-establish pathways for apoptosis, or programmed cell death, in cancer cells, and modulate the immune response against cancer cells. Oncoprex has also been shown to block mechanisms that create drug resistance. In January 2020, the FDA granted Fast Track Designation for Oncoprex™ imunogene therapy for NSCLC in combination therapy with osimertinib (AstraZeneca’s Tagrisso®). For more information, please visit the company’s web site at www.genprex.com or follow Genprex on Twitter, Facebook and LinkedIn.