Cancer is a leading cause of death worldwide. Colorectal cancer (CRC) ranks as the second leading cause of cancer death in women and the third most common tumor in men, while liver cancer is the fourth leading cause of mortality in both sexes. Standard treatments include surgery, immunotherapy, and chemotherapy, but tumors often develop resistance. Novel therapeutic strategies aim to combine treatments to prevent this resistance, as well as to improve the current therapies’ effectiveness. In the first part of this study, we report the biological effects of a new hybrid based on 2’-deoxyuridine, functionalized with a nitric oxide (NO) photo-donor moiety (dU-t-NO). We also investigated two 2’-deoxyadenosine-based hybrids (dAdo-S-NO and dAdo-t-NO) to assess their cytotoxic and cytostatic activities on the RKO (CRC) and Hep 3B2.1-7 (hepatocarcinoma, HCC) cancer cell lines. All three hybrids exhibited clear antiproliferative and cytotoxic effects, though with varying degrees of efficacy and a certain cytotype selectivity. Notably, dAdo-S-NO and dAdo-t-NO demonstrated greater effectiveness than dU-t-NO in terms of reducing cell viability, inducing apoptosis, and causing cell cycle arrest. These two hybrids also appeared to be more potent against the colon carcinoma cell line compared to the hepatocarcinoma cells. Additionally, all compounds were confirmed to release NO at micromolar concentrations. The photochemical behavior of newly synthesized dU-t-NO and the related dAdo-t-NO was further evaluated in vitro on both cell lines to assess the potential enhancement of cytotoxicity through light-triggered NO release. To this end, a custom-made irradiation apparatus for in vitro experiments was designed, and experimental conditions were carefully optimized to ensure cell safety during exposure. Data demonstrated that, despite the significant intrinsic cytostatic and cytotoxic properties of dAdo-t-NO and dU-t-NO, light-triggered release of NO did not improve their effectiveness. Continuing this line of research, we studied hybrids of Dihydroartemisinin (DHA), an active metabolite of Artemisinin, an antimalarial agent extracted from Artemisia Annua, which exhibits a stronger anti-tumor effect when used in combination with various chemotherapeutic agents. DHA has also shown the ability to reverse drug resistance in certain cancer cell lines. In this context, molecular hybridization has been employed in cancer therapy to combine DHA with other pharmacophores. In our study, eight DHA derivatives containing bile acids (BAs), which demonstrated to improve drug bioavailability, were synthesized using this technology. These hybrids were evaluated for their potential anti-cancer effects on an in vitro model of human colon carcinoma, the HCT116 cell line, and for their potential anti-angiogenic activity on human endothelial cells. All derivatives demonstrated a stronger cytostatic activity with respect to DHA on HCT116 colon carcinoma cell line. Hybrids also demonstrated to reduce HCT116 cell migration and invasion capability. On the other hand, they showed a lower effectiveness on a non-tumor cell model with respect to colon carcinoma cells, demonstrating also a lower toxicity compared to DHA. Moreover, DHA hybrids appeared to interfere with angiogenesis, which plays a crucial role in tumor progression, by reducing the proliferation and the expression of VEGF receptor-2 of endothelial cells more effectively than DHA. In conclusion, our DHA-BAs hybrids have been shown to significantly enhance DHA's cytostatic and anti-angiogenic activity, making them promising candidates for further therapeutic development.
Il cancro è una delle principali cause di morte a livello mondiale. Il cancro colorettale (CRC) rappresenta la seconda causa di morte per cancro nelle donne e la terza forma più comune di tumore negli uomini, mentre il cancro al fegato è la quarta causa di mortalità in entrambi i sessi. I trattamenti standard includono chirurgia, immunoterapia e chemioterapia, ma i tumori spesso sviluppano resistenza. Per prevenire quest’ultima, oltre che per rendere più efficaci le attuali terapie, le nuove strategie terapeutiche mirano a combinare diversi trattamenti. Nella prima parte di questo studio riportiamo gli effetti biologici di un nuovo ibrido della 2’-deossiuridina, funzionalizzato con un fotodonatore di ossido nitrico (NO), dU-t-NO. Sono stati inoltre studiati due ibridi della 2’-deossiadenosina (dAdo-S-NO e dAdo-t-NO) al fine di valutarne le attività citotossiche e citostatiche sulle linee cellulari tumorali RKO (di CRC) e Hep 3B2.1-7 (di epatocarcinoma, HCC). Tutti e tre gli ibridi hanno mostrato chiari effetti antiproliferativi e citotossici, sebbene con diversi gradi di efficacia, e una certa citoselettività. dAdo-S-NO e dAdo-t-NO hanno dimostrato una maggiore efficacia rispetto a dU-t-NO nel ridurre la vitalità cellulare, nell’indurre apoptosi e nell’arrestare il ciclo cellulare. Questi due stessi ibridi sono risultati più efficaci sulla linea di CRC rispetto a quella di HCC. Inoltre, per tutti i composti è stata confermata la capacità di rilasciare NO a concentrazioni µM. Il comportamento fotochimico del nuovo dU-t-NO e dell’ibrido correlato dAdo-t-NO è stato valutato in vitro su entrambe le linee cellulari anche per esaminare il potenziale incremento della citotossicità dovuto al rilascio di NO fotoindotto. A tale scopo, è stato progettato un apparato di irradiazione per esperimenti in vitro e le condizioni sperimentali sono state ottimizzate per garantire la sopravvivenza cellulare durante la fotoinduzione. I dati ottenuti hanno mostrato che, nonostante le intrinseche proprietà citostatiche e citotossiche di dAdo-t-NO e dU-t-NO, il rilascio di NO fotoindotto non ne ha migliorato l’efficacia. Proseguendo in questa linea di ricerca, abbiamo studiato ibridi della diidroartemisinina (DHA), metabolita attivo dell’Artemisinina, un antimalarico estratto dall’Artemisia annua, che ha mostrato un effetto antitumorale più marcato quando utilizzato in combinazione con agenti chemioterapici. La DHA ha inoltre dimostrato la capacità di contrastare la resistenza ai farmaci in alcune linee cellulari tumorali. In questo contesto, l’ibridazione molecolare è stata impiegata per combinare la DHA con altri farmacofori. Nel nostro studio, sono stati sintetizzati con tale tecnica otto derivati della DHA coniugata con acidi biliari (BAs), i quali hanno dimostrato di migliorare la biodisponibilità di farmaci. Questi ibridi sono stati valutati per i loro potenziali effetti anticancro su un modello in vitro di CRC, la linea cellulare HCT116, e per la loro potenziale attività anti-angiogenica su cellule endoteliali umane. Tutti i derivati hanno dimostrato un’attività citostatica maggiore rispetto alla DHA sulla linea cellulare HCT116. Gli ibridi hanno inoltre dimostrato di ridurre la capacità di migrazione e invasività delle cellule HCT116. Al contrario, essi si sono dimostrati meno efficaci su un modello cellulare non tumorale rispetto alle cellule di colon carcinoma, rivelandosi anche meno tossici rispetto alla DHA. Gli ibridi della DHA erano anche in grado di interferire con l’angiogenesi, che svolge un ruolo cruciale nella progressione tumorale, riducendo la proliferazione e l’espressione del recettore 2 del VEGF delle cellule endoteliali in modo più efficace rispetto alla DHA. In conclusione, i nostri ibridi DHA-BAs hanno dimostrato di potenziare significativamente l’attività citostatica e anti-angiogenica della DHA, rendendoli candidati promettenti per futuri sviluppi terapeutici.
Valutazione biologica della potenziale attività antitumorale di nuovi ibridi molecolari
POZZA, ELENA
2026
Abstract
Cancer is a leading cause of death worldwide. Colorectal cancer (CRC) ranks as the second leading cause of cancer death in women and the third most common tumor in men, while liver cancer is the fourth leading cause of mortality in both sexes. Standard treatments include surgery, immunotherapy, and chemotherapy, but tumors often develop resistance. Novel therapeutic strategies aim to combine treatments to prevent this resistance, as well as to improve the current therapies’ effectiveness. In the first part of this study, we report the biological effects of a new hybrid based on 2’-deoxyuridine, functionalized with a nitric oxide (NO) photo-donor moiety (dU-t-NO). We also investigated two 2’-deoxyadenosine-based hybrids (dAdo-S-NO and dAdo-t-NO) to assess their cytotoxic and cytostatic activities on the RKO (CRC) and Hep 3B2.1-7 (hepatocarcinoma, HCC) cancer cell lines. All three hybrids exhibited clear antiproliferative and cytotoxic effects, though with varying degrees of efficacy and a certain cytotype selectivity. Notably, dAdo-S-NO and dAdo-t-NO demonstrated greater effectiveness than dU-t-NO in terms of reducing cell viability, inducing apoptosis, and causing cell cycle arrest. These two hybrids also appeared to be more potent against the colon carcinoma cell line compared to the hepatocarcinoma cells. Additionally, all compounds were confirmed to release NO at micromolar concentrations. The photochemical behavior of newly synthesized dU-t-NO and the related dAdo-t-NO was further evaluated in vitro on both cell lines to assess the potential enhancement of cytotoxicity through light-triggered NO release. To this end, a custom-made irradiation apparatus for in vitro experiments was designed, and experimental conditions were carefully optimized to ensure cell safety during exposure. Data demonstrated that, despite the significant intrinsic cytostatic and cytotoxic properties of dAdo-t-NO and dU-t-NO, light-triggered release of NO did not improve their effectiveness. Continuing this line of research, we studied hybrids of Dihydroartemisinin (DHA), an active metabolite of Artemisinin, an antimalarial agent extracted from Artemisia Annua, which exhibits a stronger anti-tumor effect when used in combination with various chemotherapeutic agents. DHA has also shown the ability to reverse drug resistance in certain cancer cell lines. In this context, molecular hybridization has been employed in cancer therapy to combine DHA with other pharmacophores. In our study, eight DHA derivatives containing bile acids (BAs), which demonstrated to improve drug bioavailability, were synthesized using this technology. These hybrids were evaluated for their potential anti-cancer effects on an in vitro model of human colon carcinoma, the HCT116 cell line, and for their potential anti-angiogenic activity on human endothelial cells. All derivatives demonstrated a stronger cytostatic activity with respect to DHA on HCT116 colon carcinoma cell line. Hybrids also demonstrated to reduce HCT116 cell migration and invasion capability. On the other hand, they showed a lower effectiveness on a non-tumor cell model with respect to colon carcinoma cells, demonstrating also a lower toxicity compared to DHA. Moreover, DHA hybrids appeared to interfere with angiogenesis, which plays a crucial role in tumor progression, by reducing the proliferation and the expression of VEGF receptor-2 of endothelial cells more effectively than DHA. In conclusion, our DHA-BAs hybrids have been shown to significantly enhance DHA's cytostatic and anti-angiogenic activity, making them promising candidates for further therapeutic development.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
