Medicinal and Pharmaceutical Chemistry Commons^™

Development Of Novel Peptide-Doxorubicin Conjugates For Targeting Triple-Negative Breast Cancer, Azam Saghaeidehkordi

Pharmaceutical Sciences (PhD) Dissertations

Triple-negative breast cancer (TNBC) is the most aggressive and difficult to treat subtype of breast cancer. Chemotherapy is an active treatment option in combination with other treatments; however, the side effects limit the effective therapeutic dose. To selectively target the cancer cells, I have synthesized three peptide-drug conjugates (PDCs) to specifically target the TNBC cells. The first PDC contains peptide 18-4 with an additional cysteine in the N-terminal (NH2- CWxEAAYQrFL-CONH2) linked to aldoxorubicin (Aldox), a modified version of a common chemotherapy drug doxorubicin (Dox). The cytotoxicity of the PDC and free Dox (positive control) were assessed against MDA-MB-231, MDA-MB-468, and …

Modulation Of Antibacterial Activity And Cytotoxicity In Amphipathic Cyclic Peptide [R4w4] Using Histidine Substitution, Ryan Stueber

Pharmaceutical Sciences (MS) Theses

Antibiotics have been the gold standard frontline defense against bacterial infections for decades. At the same time, these infecting bacteria have continued to evolve to resist developed antibiotics in an almost endless cycle. As such, we aim to take an alternative approach utilizing antimicrobial peptides (AMPs) as a means to end this cycle. [R4W4] is among known AMPs that demonstrated antimicrobial activity against methicillin-resistant staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 2.67 μg/mL. This peptide had notably effective antimicrobial activity, especially relative to linear (R4W4). However, it displayed a concerning level of cytotoxicity; eliciting a human embryonic …

Amphiphilic Cell-Penetrating Peptides Containing Natural And Unnatural Amino Acids As Drug Delivery Tools And Antimicrobial Agents, David Salehi

Pharmaceutical Sciences (MS) Theses

Cell-penetrating peptides containing arginine as positively charged residues and tryptophan or diphenylalanine as hydrophobic residues were synthesized. The synthesis was accomplished through the Fmoc solid-phase peptide synthesis in the presence of HBTU and DIPEA. The side-chain protected linear peptides were cleaved from the resin and cyclized in the presence of DIC and HOAt in the solution phase overnight. MALDI-TOF mass spectrometry was used to characterize the peptides.

The cytotoxicity of the synthesized peptides was determined in CCRF-CEM (human, lymphoblast peripheral blood), and HEK-293 (human, embryonic epithelial kidney healthy) cells using the MTS assay. A concentration of 10 µM was found …

Amphiphilic Cell-Penetrating Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Saghar Mozaffari

Pharmaceutical Sciences (PhD) Dissertations

A number of cyclic peptides containing a positively charged ring composed of arginine residues attached to hydrophobic tail made of tryptophan residues through a lysine linker namely [R₅K]W₅, [R₆K]W₅, [R₅K]W₆, [R₇K]W₅, [R₅K]W₇, [R₆K]W₆, and [R₇K]W₇ were synthesized and evaluated as molecular transporters. The peptides were evaluated for their ability to deliver, fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F′-GpYEEI), and fluorescent labeled anti-HIV drugs (F′-FTC and F′-d4T). The results indicated that the presence of positively …