## 4 Discussion
siphonella_ was more efficient as an anticancer agent against MCF-7 and Caco-2 cancer cells, than the current methanolic one. Although each of the current _Cs_E and _Nm_E concentrations was found to inhibit cell proliferation in Caco-2, MCF-7, and HepG2 cancer cells in vitro, only three _Nm_E concentrations (6.25, 12.5, and 25 g/mL) were used in the treatment of Caco-2, MCF-7, and HepG2 cancer cells, whereas five _Cs_E concentrations (156.2, 312.5, 625, 1250, and 2500 \(\upmu\)g/mL) were used. As previously stated, the highest concentration of _Cs_E was 100 times that of _Nm_E, which may explain the significant variation in the values of IC\({}_{50}\) for the two extracts for their cell proliferation inhibition properties in HepG2, MCF-7, and Caco-2 cancer cells, where the values of IC50 for _Cs_E (271.48, 467.19, and 1570.82 g/mL), respectively, were significantly higher than that of _Nm_E (10.33, 12.48, and 10.52 \(\upmu\)g/mL), respectively. Therefore, in the current investigation, _Nm_E was chosen to undertake further anticancer screening methods, which revealed more about _Nm_E anticancer efficacy in HepG2, MCF-7, and Caco-2 cancer cells. In HepG2, MCF-7, and Caco-2 cancer cells; however, the in vitro anticancer effects of _Nm_E were supported by a decrease in CDK6, BCL2, and cyclins E1 and D1, as well as an increase in Bax, cleaved PARP, and caspase-3; in addition, the anticancer effects of other previously researched bioactive chemicals of marine species resulted in BCL2, STAT3, and MMP-9 decreases in HepG2 cancer cell line, in addition to the stimulation of G0/G1 cell cycle arrest and ROS buildup [97]. Furthermore, a study using quantitative real-time PCR analysis revealed that the administration of cerebrosides from _Asterius amurensis_ or _Acaudina molpadioides_ decreased BCL2 and Bcl-xL expression while increasing caspase-3, Cyt c, Bax, and caspase-9 expression in the murine sarcoma cell line-180 ascites [98; 99]; unlike another in vivo investigation that indicated philinopside E anti-angiogenic activity correlated with the downturn of VEGFR signaling in murine sarcoma cancer cells, the current _Nm_E was studied in vitro where it suppressed the expression of BCL2 and increased the expression of cleaved PARP, Bax, and caspase-3 in MCF-7, HepG2, and Caco-2 cancer cell lines. Even though clinical study on the anticancer efficacy of bioactive components from marine sources is highly limited, there is one study in which TBI12 was given to 20 patients with high-risk asymptomatic multiple myeloma. TBI12 was well tolerated, and 9 (45%) of the patients are still on treatment with only one minimal response [100]. As a result, the current potent _Cs_E antibacterial activities can be attributed to its GC-Mass analysis, which contains five antimicrobial molecules. The _Callyspongia siphonella_ methanol extract within its antibacterial components explains antimicrobial activities against Streptococcus mutants, Klebsiella pneumonia, and _Salmonella typhimurium_, in comparison to the antimicrobial activities of another ethanolic extract of the same sponge, including its two brominated oxindole alkaloids bioactive substances, which undoubtedly played a crucial part in robust antibacterial activity against Gram-positive bacteria, _Bacillus subtilis_ and _Staphylococcus aureus_, as well as moderate biofilm inhibitory action against _Pseudomonas aeruginosa_[39]. Furthermore, when compared to methanolic extract of _Callyspongia reticutis_, which showed less antibacterial activities in a specific fungicidal against _Candidia albicans_, _Penicillium notatum_, and _Aspergillus niger_[101], the present _Cs_E had a wider and more effective antimicrobial activity toward _Cryptococcus neoformans_, _Klebsiella pneumoniae_, _Salmonella typhimurium_, _Aspergillus flavus_, _Candidia_ spp., and _Streptococcus mutants_. Like the antimicrobial activity of _Cs_E, the sponges _Ircinia strobilinia_, _Ircinia felix_, and _Acanthella carteri_ displayed wide-spectrum antimicrobial activity toward _Candidia tropicalis_, _C.