Anticancer activity of marine endophytic fungal extracts from Malaysian seaweeds against hepG2 cells / Harmayumi Wahid

• Main Author: Wahid, Harmayumi
• Format: Thesis
• Language: English
• Published: 2021
• Subjects: Cancer
• Online Access: https://ir.uitm.edu.my/id/eprint/60182/1/60182.pdf; https://ir.uitm.edu.my/id/eprint/60182/

Marine endophytes fungi are known to be the important resource of bioactive metabolites in drug development for the pharmaceutical industry. This bioactive has the potential to treat diseases such as cancer, as an alternative to synthetic drug use in chemotherapy. This study aims to determine the potent cytotoxicity of five marine endophytic fungal extracts coded as (CN, MV, ED, CS, and UF) isolated from seaweed; Gracilaria coronopifolia, Gracilaria arcuata Zanardini, Acanthophora picifera (M.Vahl) Borgesen, Caulerpa sertularioides, and Chaemotorpha minima respectively, against human hepatocellular carcinoma cells (HepG2) and normal human liver cells (Chang), and evaluate their potential to induce apoptosis and antioxidant activity. All five marine endophytic fungi were grown in different salinity (1% and 3%) of artificial sea salt (ASS) potatoes dextrose agar (PDA). Initial cytotoxicity screening showed that 2 out of 10 marine endophytic fungal extracts (CN 1% and MV 1%) showed potential cytotoxic effect against HepG2 at 24, 48, and 72 hours incubation time with IC50 values detected for CN 1% (35.2 – 53.3 μg/ml) and MV 1% (41.8 – 50.0 μg/ml), which are <60 μg/ml. Both extracts were determined as non-toxic effect to Chang (IC50 value > 60 μg/ml). Further with cytotoxic quick screening after fractionation, CN 1% and MV 1% itself displayed higher cytotoxicity effect against HepG2 (35.5 % and 37.4 % respectively) compared to 10 selective fractions at concentration 20 μg/ml (concentration based on National Cancer Institute guidelines). Moreover, the morphological studies indicated that CN 1% and MV 1% induced apoptosis with apoptosis features such as membrane loss, condensation of cell nuclei, nuclear fragmentation, and apoptotic body formation. Furthermore, the Annexin-V assay was done to further confirm apoptosis. Data revealed, by treating with IC50 doses exhibited significant increases in early apoptosis (CN 1%= 18.7 %, MV 1%= 20.7%) and late apoptosis (CN 1%= 38.4%, MV 1%= 54.4%) entering from the viable cell, with less than 1% necrosis. Interestingly, both extracts exhibited a dose-dependent trend in early apoptosis (CN 1%= 70.9%, MV 1%= 33%) after HepG2 cells were treated with IC70 doses. Similarly, both extracts displayed ABTS radical scavenging activity with IC50 values (CN1% = 43.6 μg/ml, MV 1% = 53.5 μg/ml). Thus, the conclusion is CN 1% and MV 1% possess cell death mechanism through apoptosis induction against HepG2 at non-toxic in Chang cells, with antioxidant properties. This potential extract should be further explored in the future for marine endophytic fungus discovery for pharmaceutical application.