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Control of Gemcitabine Activity With Blue and Red Light
Nils F Kersten1, Konstantin L Stock2, Marius Hyprath3
1Institute for Organic Chemistry and Chemical Biology, Goethe-University, Frankfurt am Main, Germany.
Abstract:
Treating cancer with chemotherapy is generally associated with many side effects. This problem can be addressed by selectively releasing the desired drugs with light. In a screening approach, we modified known antimetabolite cytostatics with photoremovable protecting groups (PPGs). Sixteen new light-activatable cytostatics with a blue light-activatable diethylaminocoumarin group (DEACM) were synthesized, and their (photo-)chemical properties were tested. The most promising compounds were subjected to cytotoxicity studies with HT-29 colon cancer cells. In our experiments, the DEACM-gemcitabine derivative showed the best properties with full recovery of gemcitabine activity after irradiation. In the absence of blue light, this compound was 29 times less toxic. In the next step, based on these results, we designed a red-light activatable derivative of gemcitabine, featuring a heptamethine (Cy7) PPG. We were able to confirm the photorelease of gemcitabine with tissue-penetrating red light in HT-29 cells. Our "gem-Cy-tabine" was almost inactive in the absence of light, but its activity increased >33 fold after irradiation with red light. It is, therefore, an interesting candidate for more specific cancer therapy by photopharmacology.
Insights
Researchers developed novel light-activated chemotherapy drugs to minimize side effects. A gemcitabine derivative activated by red light shows significant potential for targeted cancer treatment, reducing toxicity in the absence of light.
Area of Science:
- Medicinal Chemistry
- Photochemistry
- Oncology
Background:
- Chemotherapy for cancer treatment often causes severe side effects.
- Selective drug delivery can mitigate these adverse effects.
- Photoremovable protecting groups (PPGs) offer a method for light-triggered drug release.
Purpose of the Study:
- To synthesize and evaluate novel light-activatable cytostatics for targeted cancer therapy.
- To develop chemotherapy drugs with reduced toxicity in the absence of light.
- To investigate the potential of photopharmacology in cancer treatment.
Main Methods:
- Synthesis of sixteen new light-activatable cytostatics using photoremovable protecting groups (PPGs), including a blue light-activatable diethylaminocoumarin (DEACM) group.
- Photochemical property testing of synthesized compounds.
- Cytotoxicity studies using HT-29 colon cancer cells to assess drug activity and light-dependent release.
- Design and synthesis of a red-light activatable gemcitabine derivative (gem-Cy-tabine) using a heptamethine (Cy7) PPG.
Main Results:
- The DEACM-gemcitabine derivative demonstrated full gemcitabine activity recovery post-irradiation and was 29 times less toxic without blue light.
- The red-light activatable gem-Cy-tabine showed minimal activity without red light, with activity increasing over 33-fold after irradiation.
- Photorelease of gemcitabine was confirmed in HT-29 cells using tissue-penetrating red light.
Conclusions:
- Novel light-activatable cytostatics, particularly gemcitabine derivatives, show promise for targeted cancer therapy.
- The developed red-light activatable gem-Cy-tabine offers a potential strategy for photopharmacology with enhanced specificity and reduced systemic toxicity.
- Further investigation into these photopharmacological agents could lead to more precise and effective cancer treatments.
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