Sinteza zaviralcev C-končne domene Hsp90 s tieno[2,3-b]piridinskim ogrodjem

Grošelj, Anja (author), Tomašič, Tihomir (mentor), Zajec, Živa (comentor)

Ena možnih tarč protirakave terapije, kateri se posveča vedno več pozornosti, je šaperon protein toplotnega šoka 90 (Hsp90). Stresni protein Hsp90 je pomemben za vzdrževanje celične proteostaze in posledično celične integritete. Pomembno vlogo ima tudi v rakavih celicah, v katerih je potreben za vzdrževanje delovanja številnih onkoproteinov. Hsp90 se v celicah nahaja v homodimerni obliki, pri čemer je vsak monomer sestavljen iz N-končne domene z ATP-azno aktivnostjo, srednje domene in C-končne domene, ki omogoča dimerizacijo. Prve učinkovine, ki so delovale na Hsp90, so bili zaviralci N-končne domene Hsp90, katerih klinični razvoj so ustavili zaradi neželenih stranskih učinkov in toksičnosti. Raziskave so se zato usmerile v alternativne načine zaviranja Hsp90, med katerimi so tudi zaviralci C-končne domene. V okviru magistrske naloge smo sintetizirali nove zaviralce C-končne domene Hsp90 s tieno[2,3-b]piridinskim ogrodjem. Antiproliferativno delovanje sintetiziranih spojin smo ovrednotili na celični liniji raka dojk MCF-7 in celični liniji Ewingovega sarkoma SK-N-MC. Ovrednotili smo jih s testom metabolne aktivnosti MTS in jim določili IC50. Iz rezultatov bioloških testiranj smo lahko postavili tri zaključke glede odnosa med strukturo in delovanjem. Najprej smo preverili vpliv halogena, ki je vezan na aromatski del spojine. Iz rezultatov na celični liniji MCF-7 smo razbrali, da imajo najmočnejše delovanje analogi z bromom, sledijo jim tisti s klorom, najnižjo pa imajo analogi s fluorom. Ugotovili smo tudi, da imajo močnejše delovanje spojine s sekundarnim aminom kot kationskim centrom napram spojinam s terciarnim aminom. Vsi sintetizirani analogi so imeli protirakavo delovanje v mikromolarnem območju, najšibkejše delovanje pa je imela spojina, ki ima para substituiran fenilni obroč na mestu 4 tieno[2,3-b]piridina. Iz tega smo sklepali, da najverjetneje obstajajo sterične ovire v alosteričnem vezavnem mestu Hsp90, ki otežujejo vezavo. Rezultati so nam omogočili boljše razumevanje odnosa med strukturo in delovanjem zaviralcev C-končne domene Hsp90 in dali izhodišča za nove raziskave.

• Language: Slovenian
• Keywords: rak, Hsp90, zaviralec, tieno[2, 3-b]piridin.
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2022
• PID: 20.500.12556/RUL-140282
• Publication date in RUL: 14.09.2022

Secondary language

• Language: English
• Title: Synthesis of Hsp90 C-terminal domain inhibitors based on the thieno[2,3 b]pyridine scaffold

Abstract

One of the available cancer targets that is becoming increasingly important in research is Hsp90, which belongs to the group of chaperones. Hsp90 is important in cells and contributes to the maintenance of cell proteostasis and cell integrity. It plays an important role in cancer cells, where it maintains the activity of many oncoproteins. In cells, Hsp90 is present in the form of a homodimer. Each monomer of the homodimer consists of the N-terminal domain with ATPase activity, the middle domain, and the C-terminal domain required for dimerization. The first compounds targeting Hsp90 were inhibitors of the N-terminal domain, but they have not been successful in clinical phases due to serious adverse effects and toxicity. Research was then directed toward alternative ways to inhibit Hsp90, one of which was inhibition of the C-terminal domain of Hsp90. In this Master's thesis, we synthesized new Hsp90 C-terminal domain inhibitors based on the thieno[2,3-b]pyridine scaffold. The antiproliferative activity was tested in the breast cancer cell line MCF-7 and the Ewing sarcoma cell line SK-N-MC. They were evaluated using the metabolic activity assay MTS and IC50 values were determined. From the results of the biological assays, we were able to draw three main conclusions about the relationship between structure and activity. First, we evaluated the effect of the halogen atom bound to the aromatic part of the structure. From the results from the MCF-7 cell line we discerned that the compounds with bromine have the highest activity. They are followed by the compounds with chlorine and the least active are those with fluorine. We also found that compounds with a secondary amine as a cationic center were more active than those with a tertiary amine. All analogs synthesized were active in the micromolar range, the least active being the compound with a para-substituted phenyl in position 4 of thieno[2,3-b]pyridine. Therefore, we concluded that there may be steric hindrances in the binding site. The results provided a better understanding of the structure-activity relationship of inhibitors of the C-terminal Hsp90 domain and offered starting points for new research.

• Keywords: cancer, Hsp90, inhibitor, thieno[2, 3-b]pyridine.