Developing Nrf2 Targeting siRNA Delivery Exosomes and Investigation of its Efficiency on Prostate Cancer

Project no. 32110 · Status: Kapanmış (Yayın bekleniyor) · 2024

Summary

<p>Prostate&nbsp;cancer&nbsp;is&nbsp;the&nbsp;second&nbsp;most&nbsp;common&nbsp;type&nbsp;of&nbsp;cancer&nbsp;in&nbsp;men,&nbsp;and&nbsp;the&nbsp;first-line&nbsp;treatment&nbsp;option&nbsp;is&nbsp;androgen&nbsp;deprivation&nbsp;therapy&nbsp;(ADT).&nbsp;However,&nbsp;due&nbsp;to&nbsp;the&nbsp;heterogeneous&nbsp;nature&nbsp;of&nbsp;prostate&nbsp;cancer,&nbsp;resistance&nbsp;to&nbsp;therapy&nbsp;develops&nbsp;over&nbsp;time,&nbsp;marking&nbsp;the&nbsp;transition&nbsp;to&nbsp;castration-resistant&nbsp;prostate&nbsp;cancer&nbsp;(CRPC).&nbsp;In&nbsp;addition,&nbsp;prostate&nbsp;cancer&nbsp;stem&nbsp;cells,&nbsp;which&nbsp;are&nbsp;part&nbsp;of&nbsp;the&nbsp;tumor’s&nbsp;heterogeneity,&nbsp;cannot&nbsp;be&nbsp;effectively&nbsp;targeted&nbsp;by&nbsp;therapies,&nbsp;leading&nbsp;to&nbsp;cancer&nbsp;recurrence.</p><p>In&nbsp;many&nbsp;cancers,&nbsp;including&nbsp;prostate&nbsp;cancer,&nbsp;oxidative&nbsp;stress&nbsp;plays&nbsp;both&nbsp;an&nbsp;initiating&nbsp;and&nbsp;promoting&nbsp;role.&nbsp;Nuclear&nbsp;factor&nbsp;erythroid&nbsp;2–related&nbsp;factor&nbsp;2&nbsp;(Nrf2)&nbsp;is&nbsp;a&nbsp;transcription&nbsp;factor&nbsp;that&nbsp;regulates&nbsp;expression&nbsp;of&nbsp;antioxidant&nbsp;enzymes&nbsp;and&nbsp;thus&nbsp;plays&nbsp;a&nbsp;critical&nbsp;role&nbsp;in&nbsp;combating&nbsp;oxidative&nbsp;stress.&nbsp;It&nbsp;is&nbsp;also&nbsp;known&nbsp;that&nbsp;Nrf2&nbsp;has&nbsp;been&nbsp;associated&nbsp;with&nbsp;the&nbsp;supporting&nbsp;the&nbsp;self-renewal&nbsp;of&nbsp;cancer&nbsp;stem&nbsp;cells.&nbsp;The&nbsp;oxidative&nbsp;condition&nbsp;induced&nbsp;by&nbsp;ADT&nbsp;and&nbsp;radiotherapy&nbsp;in&nbsp;prostate&nbsp;cancer&nbsp;treatment&nbsp;activates&nbsp;Nrf2.&nbsp;While&nbsp;Nrf2&nbsp;functions&nbsp;as&nbsp;a&nbsp;tumor&nbsp;suppressor&nbsp;in&nbsp;normal&nbsp;cells,&nbsp;its&nbsp;activation&nbsp;in&nbsp;cancer&nbsp;cells&nbsp;contributes&nbsp;to&nbsp;their&nbsp;protection&nbsp;from&nbsp;oxidative&nbsp;stress&nbsp;and&nbsp;chemotherapeutic&nbsp;agents,&nbsp;thereby&nbsp;supporting&nbsp;cancer&nbsp;cell&nbsp;survival.&nbsp;Based&nbsp;on&nbsp;this,&nbsp;Nrf2&nbsp;activation&nbsp;is&nbsp;considered&nbsp;one&nbsp;of&nbsp;the&nbsp;mechanisms&nbsp;responsible&nbsp;for&nbsp;prostate&nbsp;cancer&nbsp;progression&nbsp;and&nbsp;therapeutic&nbsp;resistance.</p><p>Exosomes&nbsp;are&nbsp;extracellular&nbsp;vesicles&nbsp;ranging&nbsp;from&nbsp;30&nbsp;to&nbsp;120&nbsp;nm&nbsp;in&nbsp;size,&nbsp;secreted&nbsp;by&nbsp;various&nbsp;cell&nbsp;types,&nbsp;and&nbsp;play&nbsp;roles&nbsp;in&nbsp;intercellular&nbsp;communication.&nbsp;Due&nbsp;to&nbsp;their&nbsp;biocompatibility&nbsp;with&nbsp;cell&nbsp;membranes,&nbsp;they&nbsp;have&nbsp;recently&nbsp;gained&nbsp;attention&nbsp;as&nbsp;potential&nbsp;drug&nbsp;delivery&nbsp;systems.&nbsp;Studies&nbsp;have&nbsp;shown&nbsp;that&nbsp;cancer&nbsp;cell-derived&nbsp;exosomes&nbsp;exhibit&nbsp;preferential&nbsp;tropism&nbsp;toward&nbsp;their&nbsp;parent&nbsp;cancer&nbsp;cells/&nbsp;interact&nbsp;more&nbsp;strongly&nbsp;with&nbsp;their&nbsp;parent&nbsp;cancer&nbsp;cells&nbsp;compared&nbsp;to&nbsp;those&nbsp;from&nbsp;other&nbsp;cell&nbsp;types,&nbsp;suggesting&nbsp;their&nbsp;potential&nbsp;as&nbsp;targeted&nbsp;delivery&nbsp;systems&nbsp;for&nbsp;cancer&nbsp;therapy.</p><p>In&nbsp;this&nbsp;thesis,&nbsp;prostate&nbsp;cancer&nbsp;cell&nbsp;derived&nbsp;exosome-based&nbsp;drug&nbsp;delivery&nbsp;system&nbsp;was&nbsp;developed&nbsp;to&nbsp;suppress&nbsp;Nrf2&nbsp;expression,&nbsp;thereby&nbsp;counteracting&nbsp;the&nbsp;pro-tumorigenic&nbsp;effects&nbsp;of&nbsp;Nrf2&nbsp;activation&nbsp;in&nbsp;prostate&nbsp;cancer.&nbsp;The&nbsp;aim&nbsp;was&nbsp;to&nbsp;develop&nbsp;a&nbsp;more&nbsp;effective&nbsp;treatment&nbsp;strategy&nbsp;that&nbsp;capable&nbsp;of&nbsp;targeting&nbsp;both&nbsp;tumor&nbsp;cells&nbsp;and&nbsp;cancer&nbsp;stem&nbsp;cells,&nbsp;ultimately&nbsp;preventing&nbsp;therapeutic&nbsp;resistance&nbsp;and&nbsp;metastasis.&nbsp;Exosomes&nbsp;were&nbsp;isolated&nbsp;from&nbsp;LNCaP&nbsp;cells&nbsp;using&nbsp;an&nbsp;ultracentrifugation&nbsp;method&nbsp;and&nbsp;characterized.&nbsp;Subsequently,&nbsp;siNrf2&nbsp;was&nbsp;loaded&nbsp;into&nbsp;the&nbsp;exosomes&nbsp;using&nbsp;a&nbsp;commercial&nbsp;transfection&nbsp;reagent.&nbsp;The&nbsp;efficacy&nbsp;of&nbsp;the&nbsp;developed&nbsp;siNrf2-loaded&nbsp;exosomes&nbsp;on&nbsp;prostate&nbsp;cancer&nbsp;cells&nbsp;was&nbsp;then&nbsp;evaluated&nbsp;by&nbsp;assessing&nbsp;their&nbsp;effects&nbsp;on&nbsp;Nrf2&nbsp;activity&nbsp;at&nbsp;both&nbsp;mRNA&nbsp;and&nbsp;protein&nbsp;levels.</p>

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