[Rapamycin enhances inhibitory effect of RSL3 on proliferation, invasion and migration of testicular cancer I-10 cells in vitro]

OBJECTIVE

To investigate the effect of rapamycin for enhancing the inhibitory effect of RSL3 on proliferation, invasion and migration of testicular cancer I-10 cells in vitro.

METHODS

I-10 cells treated with 0-16 μmol/L RSL3 (Type Ⅱ) either alone or in combination with 16 μmol/L rapamycin (RAPA) were examined for changes in proliferation using MTT assay and colonyforming assay, and the changes in cell migration and invasion abilities were detected with wounding-healing assay and Transwell assay. The changes in the levels of lipid reactive oxygen species in the treated cells were detected using flow cytometry. GSH and MDA contents in the cells were detected using commercial detection kits, and GPX4 protein expression level was determined with Western blotting.

RESULTS

The cytotoxic effect of RSL3 increased dose-dependently in I-10 cells, and the combined treatment with rapamycin further enhanced its cytotoxicity. Treatment of I-10 cells with RSL3 alone significantly decreased cell colony numbers (P < 0.05), wounding-healing rates (P < 0.01), and invasion and migration cell numbers (P < 0.05), increased lipid reactive oxygen species level and MDA content (P < 0.05), and lowered GSH content and expression level of GPX4 protein in the cells (P < 0.01). The inhibitory effects of RSL3 were significantly enhanced by co-treatment of the cells with rapamycin (P < 0.05 or 0.01).

CONCLUSION

Rapamycin enhances the inhibitory effect of RSL3 on proliferation, invasion and migration of I-10 cells by enhancing RSL3-mediated cell ferroptosis.

[The one-stage technology of epiglottis function and voice reconstruction after total laryngectomy with the sternohyoid myocutaneous flap]

Objective:To investigate the clinical effect of one-stage sternohyoid musculocutaneous flap after total laryngectomy for reconstruction of epiglottis function and vocalization. Methods:A retrospective analysis of 8 patients who underwent total laryngectomy from November 2019 to September 2020. The sternohyoid myocutaneous flap was designed after total laryngectomy. The lower edge of the flap was sewed with the posterior upper edge of the tracheostomy opening, and the lateral and medial edges of the flap were anastomosed to create a vocal tube. The lateral edge of the upper end of tube was sutured with the anterolateral wall of the hypopharynx, then made full use of residual epiglottis and tongue root tissue to reconstruct epiglottis function. Results:None of the 8 patients had serious complications after total laryngectomies. Fifteen months after operation,the vocal tube flaps survived and had intact structure under fiberoptic laryngoscope. All patients could speak clearly and forcefully, and the swallowing function was intact. Conclusion:The use of adjacent myocutaneous flap to construct the vocal canal and reconstruct the epiglottis function is a simple and effective technique that can be completed in one stage and improve the voicing of patients undergoing total laryngectomy.

[Carbenoxolone enhances inhibitory effect of RSL3 against cisplatin-resistant testicular cancer cells by promoting ferroptosis]

OBJECTIVE

To investigate the inhibitory effect of RSL3 on the proliferation, invasion and migration of cisplatinresistant testicular cancer cells (I-10/DDP) and the effect of carbenoxolone on the activity of RSL3 against testicular cancer.

METHODS

MTT assay was used to evaluate the survival rate of I-10/DDP cells following treatment with RSL3 (1, 2, 4, 8, 16 or 32 μmol/L) alone or in combination with carbenoxolone (100 μmol/L) or after treatment with Fer-1 (2 μmol/L), RSL3 (4 μmol/L), RSL3+Fer-1, RSL3+carbenoxolone (100 μmol/L), or RSL3+Fer-1+carbenoxolone. Colony formation assay was used to assess the proliferation ability of the treated cells; wounding-healing assay and Transwell assay were used to assess the invasion and migration ability of the cells. The expression of GPX4 was detected using Western blotting, the levels of lipid ROS were detected using C11 BODIPY 581/591 fluorescent probe, and the levels of Fe²⁺ were determined with FerroOrange fluorescent probe.

RESULTS

RSL3 dose-dependently decreased the survival rate of I-10/DDP cells, and the combined treatment with 2, 4, or 8 μmol/L RSL3 with carbenoxolone, as compared with RSL3 treatment alone, resulted in significant reduction of the cell survival rate. The combination with carbenoxolone significantly enhanced the inhibitory effect of RSL3 on colony formation, wound healing rate (P=0.005), invasion and migration of the cells (P < 0.001). Fer-1 obviously attenuated the inhibitory effects of RSL3 alone and its combination with carbenoxolone on I-10/DDP cells (P < 0.01). RSL3 treatment significantly decreased GPX4 expression (P=0.001) and increased lipid ROS level (P=0.001) and Fe²⁺ level in the cells, and these effects were further enhanced by the combined treatment with carbenoxolone (P < 0.01).

CONCLUSION

Carbenoxolone enhances the inhibitory effect of RSL3 on the proliferation, invasion and migration of cisplatin-resistant testicular cancer cells by promoting RSL3-induced ferroptosis.

[Assessment of lymphocytic function in vitro stimulated by specific tumor polypeptide combined with dendritic cells]

OBJECTIVE

To assess the activation function of specific tumor polypeptide for dendritic cell vaccine on lymphocytes proliferation, production of cytokines and killing activity in vitro by using dendritic cells as antigen presenting vector.

METHODS

Peripheral blood dendritic cells (DC) and cytokine-induced killer (CIK) were isolated and cultured by adherent culture method; CCK-8 method was used to assess the proliferation function of lymphocytes and the killing function of lymphocytes to tumor cells; enzyme-linked immunospot assay method was used to evaluate the secretion function of cytokines. The experiment was divided into tumor polypeptide group (peptide with DC-CIK), DC-CIK group and CIK group.

RESULTS

With presence of interleukin-2 (IL-2) in the culture system, the lymphocyte proliferation of the three groups was obvious. The absorbance at 450 nm of tumor polypeptide group was significantly higher than that of CIK group at the time points day 4 and day 6 (day 4: Z=-3.79, P < 0.001; day 6: Z =-2.95, P < 0.01). The absorbance at 450 nm of group tumor polypeptide was significantly higher than that of DC-CIK group on day 4 (Z=-2.02, P < 0.05). Without IL-2 in the culture system, lymphocytes proliferated slowly in all the three groups, and there was no significant difference in 450 nm absorbance at each time point. The levels of IL-4 (Z=-2.61, P < 0.01), granulocyte-macrophage colony-stimulation factor (GM-CSF, Z=-3.85, P < 0.001), interferon- γ (IFN- γ, Z=-3.56, P < 0.001) and tumor necrosis factor-α (TNF-ɑ, Z=-3.40, P < 0.001) of tumor polypeptide group were higher than those of CIK group. There was no significant difference in the production of cytokines except IL-4 (Z=-2.15, P < 0.05) when tumor polypeptide group was compared with DC-CIK group. The production of IFN-γ (Z=-2.44, P < 0.05), TNF-ɑ (Z=-2.26, P < 0.05) and GM-CSF (Z=-3.73, P < 0.001) in DC-CIK group were higher than those of CIK group. Although there was no significant difference in killing activity between tumor polypeptide group, DC-CIK group and CIK group at hour 18 and hour 24, and the killing activity of tumor polypeptide group was higher than that of the other two groups.

CONCLUSION

Tumor peptide combined with dendritic cells can improve the proliferation activity of CIK cells in vitro, and increase the secretion of several cytokines.

[Joint optic disc and cup segmentation based on residual multi-scale fully convolutional neural network]

Glaucoma is the leading cause of irreversible blindness, but its early symptoms are not obvious and are easily overlooked, so early screening for glaucoma is particularly important. The cup to disc ratio is an important indicator for clinical glaucoma screening, and accurate segmentation of the optic cup and disc is the key to calculating the cup to disc ratio. In this paper, a full convolutional neural network with residual multi-scale convolution module was proposed for the optic cup and disc segmentation. First, the fundus image was contrast enhanced and polar transformation was introduced. Subsequently, W-Net was used as the backbone network, which replaced the standard convolution unit with the residual multi-scale full convolution module, the input port was added to the image pyramid to construct the multi-scale input, and the side output layer was used as the early classifier to generate the local prediction output. Finally, a new multi-tag loss function was proposed to guide network segmentation. The mean intersection over union of the optic cup and disc segmentation in the REFUGE dataset was 0.904 0 and 0.955 3 respectively, and the overlapping error was 0.178 0 and 0.066 5 respectively. The results show that this method not only realizes the joint segmentation of cup and disc, but also improves the segmentation accuracy effectively, which could be helpful for the promotion of large-scale early glaucoma screening.