In vitro assessment of benzothiadiazole-based photoactive polymers against ovarian, prostate and bladder cancer cell lines for photodynamic therapy

There are unmet clinical needs of bladder cancer associated with its late detection, limited treatment options, and high mortality rate. In response to this, we present the results of the in-vitro assessment of photodynamic polymers, prior to their integration into a wireless biomedical implant for in-situ photodynamic therapy (PDT). PDT selectively activates light-sensitive photosensitizers, to kill cancer cells without the adverse effects associated with systemic therapies, such as chemotherapy. PDT offers significant advantages in hypoxic tumors, including oxygen-independent cytotoxicity known to impede the curative efficiency of radiotherapy. Accordingly, we report on the design methodology and microfabrication process of an in-situ PDT wireless microsystem as a novel treatment modality. We present the preliminary results from three benzothiadiazole-based polymers that are evaluated as solid support photosensitizers for the inhibition of cancer growth in three cell lines. Cell lines represent ovarian, prostate and bladder cancer, the reduction in cell number was assessed with Sulforhodamine B assays. Following Polyamide, aminophenyl- (PA-ABT) treatment, cells were subjected to a range of 420 nm light exposures and fluorimetry was used to determine cell growth. PA-ABT was shown to cause growth inhibition only at higher concentrations in all tested cell lines. PA-ABT can be considered as a promising candidate for in-situ PDT treatment due to its inhibitory effects in cancer cell lines open new possibilities for mono or combination light-based therapy in cancer treatment for previously inaccessible cancers.