Objective:

2

To study the

in vitro

and

in vivo

antitumor effects of the polysaccharide of

Alocasia cucullata

(PAC) and the underlying mechanism.

Methods:

2

B16F10 and 4T1 cells were cultured with PAC of 40 μg/mL

and PAC was withdrawn after 40 days of administration. The cell viability was detected by cell counting kit-8. The expression of Bcl-2 and Caspase-3 proteins were detected by Western blot and the expressions of ERK1/2 mRNA were detected by quantitative real-time polymerase chain reaction (qRT-PCR). A mouse melanoma model was established to study the effect of PAC during long-time administration. Mice were divided into 3 treatment groups: control group treated with normal saline

positive control group (LNT group) treated with lentinan at 100 mg/(kg • d)

and PAC group treated with PAC at 120 mg/(kg • d). The pathological changes of tumor tissues were observed by hematoxylin-eosin staining. The cell apoptosis of tumor tissues was detected by TUNEL staining. Bcl-2 and Caspase-3 protein expressions were detected by immunohistochemistry

and the expressions of ERK1/2

JNK1 and p38 mRNA were detected by qRT-PCR.

Results:

2

In vitro

no strong inhibitory effects of PAC were found in various tumor cells after 48 or 72 h of administration. Interestingly however

after 40 days of cultivation under PAC

an inhibitory effect on B16F10 cells was found. Correspondingly

the long-time administration of PAC led to downregulation of Bcl-2 protein (

P

<

0.05)

up-regulation of Caspase-3 protein (

P

<

0.05) and ERK1 mRNA (

P

<

0.05) in B16F10 cells. The above results were verified by

in vivo

experiments. In addition

viability of B16F10 cells under long-time administration culture

in vitro

decreased after drug withdrawal

and similar results were also observed in 4T1 cells.

Conclusions:

2

Long-time administration of PAC can significantly inhibit viability and promote apoptosis of tumor cells

and had obvious antitumor effect in tumor-bearing mice.