Photodynamic therapy (PDT) is a treatment for superficial tumours involving the administration of a photosensitiser followed by irradiation.

The potential of the natural anthraquinone parietin (PTN) in PDT is still relatively unexploited. In the present work, PTN isolated from the lichen Teoloschistes nodulifer (Nyl.) Hillman (Telochistaceae) was evaluated as a potential photosensitiser on tumour cells employing UVA-Vis and blue light.

Blue light of 2 J/cm² induced 50% death of K562 leukaemic cells treated 1 h with 30 μM PTN (Protocol a). Higher light doses (8 J/cm²) were needed to achieve the same percentage of cell death employing lower PTN concentrations (3 μM) and higher exposure times (24 h) (Protocol b). Cell cycle analysis after both protocols of PTN-PDT revealed a high percentage of sub-G1 cells. PTN was found to be taken up by K562 cells mainly by passive diffusion.

Other tumour cells such as ovary cancer IGROV-1 and LM2 mammary carcinoma, as well as the normal keratinocytes HaCaT, were also photosensitised with PTN-PDT.

We conclude that PTN is a promising photosensitiser for PDT of superficial malignancies and purging of leukaemic cells, when illuminated with blue light. Thus, this light wavelength is proposed to replace the Vis-UVA lamps generally employed for the photosensitisation of anthraquinones.

光动力疗法（PDT）是一种浅表肿瘤的治疗方法，包括先给予光敏剂再进行照射。

PDT中天然蒽醌类磷脂（PTN）的潜力仍未得到开发。在当前的工作中，使用UVA-Vis和蓝光评估了从地衣Teoloschistes nodulifer（Nyl。）Hillman（Telochistaceae）分离的PTN作为对肿瘤细胞的潜在光敏剂。

2 J / cm ^2的蓝光诱导用30μMPTN（协议a）处理1 h的K562白血病细胞死亡50％。使用较低的PTN浓度（3μM）和较高的曝光时间（24 h），需要更高的光剂量（8 J / cm ²）才能达到相同的细胞死亡百分比（协议b）。两种PTN-PDT方案后的细胞周期分析均显示亚G1细胞百分比较高。发现PTN主要通过被动扩散被K562细胞吸收。

其他肿瘤细胞，例如卵巢癌IGROV-1和LM2乳腺癌，以及正常的角质形成细胞HaCaT，也用PTN-PDT光敏化。

我们得出的结论是，当用蓝光照射时，PTN是一种有前景的光敏剂，可用于浅表恶性肿瘤的PDT和清除白血病细胞。因此，提出了该光波长以代替通常用于蒽醌的光敏化的Vis-UVA灯。