Antitumor Immunity and Therapeutic Properties of Marine Seaweeds-derived Extracts in The Treatment of Cancer

Abstract Marine seaweeds are important sources of drugs with several pharmacological characteristics.The present study aims to evaluate the antitumor and antitumor immunological potentials of the extracts from Padina pavonia and Jania rubens inhibiting the Egyptian marine coasts. Hep-G2 cell lines used for assessment of the antitumor efficacy of Padina pavonia and Jania rubens extracts in vitro, while Ehrlich ascites carcinoma (EAC) cells were applied to gain more antitumor immunity and antitumor insights of P. pavonia and J.rubens extracts in vivo. In vitro antitumor potentials of P. pavonia and J. rubens extracts were analyzed against human liver cancer Hep-G2 cells by MTT and trypan blue exclusion assays. In vivo antitumor immunological potentials of P. pavonia and J. rubens extracts at low, high, and prophylactic doses were analyzed by blood counting and flow cytometry in mice challenged with Ehrlich ascites carcinoma (EAC) cells. In vitro results revealed that P. pavonia and J. rubens extracts caused significant decreases in the number and viability of Hep-G2 cells in a dose-dependent manner as compared to untreated Hep-G2 cells or Cisplatin®-treated Hep-G2 cells. In vivo findings showed that P. pavonia and J. rubens extracts at low, high, and prophylactic doses significantly reduced the number and viability of EAC tumor cells accompanied by increases in EAC apoptosis compared to naïve EAC mouse. Additionally, P. pavonia and J. rubens extracts at low and prophylactic doses remarkably increased both the total WBC count and the relative numbers of lymphocytes and decreased the relative numbers of neutrophils and monocytes. Flow cytometric analysis showed that P. pavonia and J. rubens extracts at the treatment and the prophylactic doses resulted in a significant increase in the phenotypic expressions of CD4+ T, CD8+ T, and CD335 cells compared to naïve EAC mouse. Overall, both extracts P. pavonia and J. rubens possess potential antitumor and antitumor immunological effects with less toxicity, opening new approaches for further studies of the chemical and biological mechanisms behind these effects.