Evaluation of the potential for immunogenic cell death induction of low molecular weight sulfated galactan in human breast cancer

Sulfated galactan (SG) from Gracilaria fisheri has the potential for cancer cell therapy since its discovery [ 1 ] [ 2 ]. Our previous study showed that low molecular weight of SG (LMSG) could enhance biological activities, such as antioxidant activity [ 3 ]. In this study, we aimed to evaluate the anticancer activity of LMSG, particularly its ability to induce immunogenic cell death. LMSG, prepared using HCl-controlled degradation, was characterized by FTIR, NMR, and GPC analyses, while its anti-breast cancer activity was assessed using normal breast MCF-10A cells, as well as breast cancer MCF-7 and MDA-MB 231 cell cultures. Additionally, the expression of immunogenic cell death proteins (Fas-R, CRT, and MHC class-I) was determined after treatment with LMSG in MDA-MB 231 cells using qPCR, Western blot, and confocal microscopy assays. The results revealed that LMSG was not cytotoxic to normal breast MCF-10A cells, while it was slightly cytotoxic to human breast cancer MCF-7 and MDA-MB 231 cells. Cytotoxicity in cancer cells, indicated by morphological changes, correlated with cell number reduction and cell death. The expression levels of Fas-R and CRT were upregulated in the LMSG treatment group, similar to the positive doxorubicin control. However, the expression levels of MHC class-I did not change in any of the groups. In conclusion, our results suggest that LMSG has the potential to enhance the expression of immunogenic cell death in human breast cancer and could be used as an adjuvant for cancer cell therapy. Finally, the authors declare that they have no competing interests. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany