Louisiana Research Day Program Book 2025

Biomedical Research: Section 1

Biomedical Research: Section 1

Hamza Mehmood, OMS-II 1 ; Ishrar Shaid, OMS-II 1 ; Mohammed Almosa, OMS-II 1 ; Oliver McGhee 2 ; Hassan Ebrahim, PhD 1 ; Khalid El Sayed, PhD 2 1 VCOM-Louisiana; 2 ULM College of Pharmacy 9 THE DIBENZOFURAN LICHEN ACID: A NOVEL SCAFFOLD FOR THE CONTROL OF TRIPLE-NEGATIVE BREAST MALIGNANCIES

David Kang, OMS-II; Vishveshvar Ramkumar, OMS-II; Jedidiah Lim, OMS-II; Aditi Patel, OMS-II; Dalal Dawud, Pharm D; Hassan Ebrahim, PhD; Zakaria Abd Elmageed, PhD VCOM-Louisiana 8 ROSEMARY: A TIMELESS HERB WITH A PROMISING ANTI-BREAST CANCER PROPERTIES

Context: Breast cancer (BC) is the most common cancer diagnosed among American women. Approximately 1 in 8 American women will be diagnosed with BC in her lifetime and 1 in 43 will die from the disease complications. BC encompasses various disease subtypes with different biological, clinical and prognostic characteristics. Despite significant progress over the past several decades in reducing BC mortality, multiple disease challenges remain unmet including the development of resistance to the current standard therapy, intolerability and high rate of recurrence. Dietary phytochemicals have been proven for their potential health benefits, including antioxidant, anti-inflammatory, antiviral, anticancer, and immunomodulation. Phytochemicals harbor an amalgam of diverse biomolecules with the potential capacity to modulate the intricate biological systems in an efficient and selective manner. Objectives and/ or Hypothesis: Previous studies supported the significant role of rosemary-derived phytochemicals in modulating various human diseases, including cancer. Herein we aimed at identifying bioactive phytochemicals in rosemary extract that are more likely to

mediate the anti-BC activity of the herb and investigating their molecular targets.

the polyphenolic rosmarinic acid (RA). RA significantly suppressed proliferation of human BC cell line panel at low µM doses, with MDA MB-231 being the most sensitive BC cell line with IC50 value of 33.2 µM. Additionally, RA inhibited the migration of MDA-MB-231 cells in the scratch assay at 21.7 µM, while effectively suppressed the cell colonization at 11.5 µM. The computational modeling predicted the MDA-MB-231 overexpressed receptor tyrosine kinase c-Met as a potential target for RA in these cells. Western blot analyses successfully validated the target, where RA downregulated the phosphorylated c-Met in a concentration dependent manner. Conclusion: Dietary phytochemicals will remain an innovative resource for the discovery of anticancer biomolecules. The rosemary-derived RA is a novel c-Met tyrosine kinase inhibitor with potential anti-BC activity against c-Met overexpressing triple-negative BC cells. Further preclinical validation is highly warranted to promote the polyphenolic RA to the drug lead rank.

Context: Breast cancer (BC) remains the most commonly diagnosed cancer in American women, with over 40,000 deaths projected in 2025. BC encompasses various disease subtypes with distinct biological, clinical and prognostic characteristics. Among these, triple negative breast cancer (TNBC) is characterized by the lack of positive staining for the estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor 2 (HER2). This lack of targetable receptors renders TNBC inherently resistant to the current BC- targeted therapies, resulting in poorer recurrence-free and overall survival rates compared to other BC subtypes. The receptor tyrosine kinase c-Met, a membrane-bound receptor activated by hepatocyte growth factor (HGF), plays a crucial role in promoting cell proliferation, survival, motility, and angiogenesis. c-Met is frequently overexpressed or dysregulated in TNBC, making it a compelling therapeutic target. Lichens, a symbiotic association between a fungus (mycobiont) and a photosynthetic partner (photobiont, typically alga or cyanobacterium), serve as a unique resource of the discovery of bioactive compounds.

Objectives and/or Hypothesis: Our previous studies identified the dibenzofuran usnic acid (UA) from Louisiana-grown lichens and developed more than 50 chemically optimized analogs with notable anticancer activity, selectively targeting TNBC cells. This study aims to further investigate the molecular targets of these analogs that are most likely mediating their anticancer mechanism. Methods: Analog U26 was synthesized using Claisen-Schmidt carbon-carbon coupling, and its identity was confirmed by NMR and mass spectrometry. Phenotypic screening assays, including cell proliferation, migration and colonization, were implemented to evaluate the anticancer effect of U26 on TNBC cells. Additionally, immunoblotting was utilized to investigate the proteomic profile of TNBC cells treated with U26. Results: U26 was successfully synthesized and demonstrated significant suppression of TNBC cell proliferation, migration and colonization at sub-micromolar levels. Western blot analyses revealed a dose dependent downregulation of c-Met receptor tyrosine kinase in U26-terated TNBC cells.

Conclusion: Natural products and their analogs continue to serve as valuable resources for discovering novel anticancer biomolecules. The lichen-derived dibenzofuran usnic acid analogs, such as U26, are potential c-Met modulators for TNBC treatment. Further preclinical studies are necessary to validate U26 as a lead compound for therapeutic development.

Methods: Polarity-based fractionation of the rosemary extract was accomplished by liquid liquid extraction. The pooled fractions were then tested against multiple human BC cells and bioactive sub-fractions were subjected to extensive chromatographic purification to yield bioactive molecules, which were subsequently evaluated in different cell-free and cell based bioassays including cell proliferation, migration and colonization. The potential macromolecular targets of these purified phytochemicals were disclosed utilizing computational and Western blot analyses. Results: The partition extraction of rosemary yielded four fractions: hexane, ethyl acetate, n-butanol and water. The butanol fraction showed the most promising anticancer cancer activity against MCF-7, MDA-MB-231, MDA MB-468 and BT-474 human BC cell lines in proliferation assays with IC50 values of 104.2, 43.7, 45.9, and 91.6 µg/mL, respectively. Further chromatographic separation identified different phytochemicals, including

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2025 Research Recognition Day