Interfering with the expression of EEF1D gene enhances the sensitivity of ovarian cancer cells to cisplatin

Background

Eukaryotic translation elongation factors 1 δ (EEF1D), has garnered much attention with regards to their role in the drug resistance of cancers. In this paper, we investigated the effects and mechanisms of increasing the sensitivity of ovarian cancer cells to cisplatin or cis-dichlorodiammine platinum (DDP) by knockdown and knockout of EEF1D gene in cellular and animal models.

Methods

The EEF1D gene was knocked-down or -out by siRNA or CRISPR/Cas9 respectively in human ovarian cancer cell SKOV3, DDP-resistant subline SKOV3/DDP, and EEF1D gene in human primary ovarian cancer cell from 5 ovarian cancer patients with progressive disease/stable disease (PD/SD) was transiently knocked down by siRNA interference. The mice model bearing xenografted tumor was established with subcutaneous inoculation of SKOV3/DDP.

Results

The results show that reducing or removing EEF1D gene expression significantly increased the sensitivity of human ovarian cancer cells to DDP in inhibiting viability and inducing apoptosis in vitro and in vivo, and also boosted DDP to inhibit xenografted tumor growth. Interfering with EEF1D gene expression in mice xenografted tumor significantly affected the levels of OPTN, p-Akt, Bcl-2, Bax, cleaved caspase-3 and ERCC1 compared to DDP treated mice alone, and had less effect on PI3K, Akt and caspase-3.

Conclusions

The knocking down or out EEF1D gene expression could enhance the sensitivity of ovarian cancer cells to DDP partially, which may be achieved via inactivating the PI3K/AKT signaling pathway, thus inducing cell apoptosis and decreasing repairment of DNA damage. Our study provides a novel therapeutic strategy for the treatment of ovarian cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09699-7.

Effects of different doses of propofol on the growth and expression of PCNA, CD34 and pAKT proteins in xenografted tumor of BALB/C mice with liver cancer

OBJECTIVE

To observe the effects of different doses of propofol on the growth of transplanted liver tumor in BALB/C mice and check the expression of PCNA, CD34 and pAKT proteins to clarify the mechanism on molecule level.

METHOD

Human primary liver cancer cells SMMC-7721 were subcutaneously cultured in BALB/C mice, and the transplanted tumor model of BALB/C mice was constructed. Forty mice successfully modeled were randomly divided into 5 groups (n = 8): the blank control group (group C), low-fat milk group (group I), low-dose (50 mg/kg) propofol group (P1), middle-dose (100 mg/kg) propofol group (P2) and high dose (150 mg/kg) propofol group (P3). Tumor volume changes were observed at 3, 6, 9, 12, 15 and 18 days (T1, T2, T3, T4, T5, T6 and T7) before and after administration of the drug, and tumor growth curves were plotted. After 19 days of administration, all mice were killed for tumor collection, tumor weight was measured, and the tumor inhibition rate of propofol was calculated. The protein expression of cluster of differentiation 34 (CD34) in transplanted tumor was detected by immunohistochemistry, and the protein expression of proliferating cell nuclear antigen (PCNA) and phospho-Akt (pAKT) was detected by immunofluorescence.

RESULTS

Compared with group C, there was no significant difference in tumor volume in group I. At T2 ~ 7, the tumor volume of group P1, P2 and P3 decreased successively (P < 0.05). There was no significant difference in the inhibitory rate of tumor in group I, and the inhibitory rate of tumor in group P1, P2 and P3 increased successively (P < 0.05). There was no significant difference in PCNA, CD34, and pAKT protein expression in group I, while PCNA, CD34, and pAKT protein content in P1, P2, P3 groups were successively decreased (P < 0.05).

CONCLUSION

Propofol had a dose-dependent effect on the growth of liver cancer xenografts in mice, inhibiting the expression of PCNA, CD34 and pAKT proteins, and the effect was most obvious in the 150 mg/kg propofol group.