Application Of Modified Closed Biopsy In Rabbit Model Of VX2 Transplanted Bone Tumor

Part I An animal experimental study on a closed puncture biopsy instrumentObjective:To verify the feasibility of a closed biopsy device for bone tumor in animal experiments,and to explore the expression and significance of CD34,PCNA,IFN-γ and IL-4 in rabbit VX2 bone tumor model.Methods:VX2 tumor tissue was implanted into the left tibia of 10 Japanese white rabbits through the tibial plateau to make bone tumor model.7days after operation,use the closed bone tumor biopsy device to obtain bone tissue and bone marrow supernatant for puncture biopsy(group A).14 days after operation,bone tissue and bone marrow supernatant around the puncture channel were obtained by open biopsy(group B).Stained the bone marrow and bone tissue samples and normal bone marrow tissue of the two groups by HE pathology,and then examined for tumor cell infiltration under microscope.Moreover,the two groups of bone marrow samples and normal bone marrow samples were centrifuged,and use the Enzyme linked immunosorbent assay(ELISA)to detect the contents of CD34,PCNA,IFN-γ and IL-4 in the supernatant.Results:The mold forming rate of 10 rabbits was 100%.Compared with preoperation,A large number of tumor cells were seen under microscope after bone marrow HE staining.The infiltration degree of tumor cells in bone tissue of group A was higher than that of group B,and the difference in the detection rate of tumor cells in bone tissue samples between the two groups was statistically significant(P<0.05).The results of ELISA assay showed that the contents of CD34,PCNA,IFN-γ and IL-4 in the supernatant extracted from normal bone marrow were 77.09±7.75ng/ m L,60.89±3.27ng/m L,133.30±9.58ng/L and 36.87±5.28ng/L,respectively.The corresponding protein contents in the supernatant of bone marrow extraction in group A were 85.06±4.45 ng/m L,80.96±5.91 ng/m L,169.82±2.26 ng/L and47.72±0.78 ng/L,respectively.The contents of CD34,PCNA,IFN-γ and IL-4 in the supernatant extracted from bone marrow of group A were significantly higher than those in the normal supernatant,with statistical significance(P<0.05).The corresponding protein content in the supernatant of bone marrow extracted from group B was 91.30±7.65ng/ m L,80.96±5.91ng/ m L,145.82±2.26ng/L and 63.33±3.07ng/L,respectively.The contents of CD34,PCNA and IL-4 in bone marrow supernatant of group B were significantly higher than those of group A,with statistical significance(P<0.05).IFN-γ in bone marrow supernatant of group B was significantly lower than that of group A,and the difference was statistically significant(P<0.05).Conclusion:(1)The closed bone tumor biopsy device can effectively obtain and detect the pathological tissue of bone tumor,and avoid the pollution of tumor to the puncture channel.It is a feasible bone tumor biopsy method.(2)Within 14 days after the establishment of the rabbit VX2 bone tumor model,with the rapid proliferation of the tumor,the anti-tumor immune function of the body was gradually inhibited,which showed that the expression level of IL-4 was increased,and the expression level of IFN-γwas firstly increased and then decreased.Part II Application of modified closed biopsy in rabbit model of VX2 transplanted bone tumorObjective:To explore the application value of modified closed biopsy technique in puncture biopsy of rabbit VX2 transplanted bone tumor model.Methods:VX2 tumors from subcultured tumor-bearing rabbits were surgically transplanted into the bilateral tibia of 30 rabbits to make tumor animal models.Seven days after modeling,the proximal tibia biopsy was performed under the guidance of X-ray,and the biopsy specimen was examined pathologically.The left leg was biopsied with modified closed biopsy technique(experimental group)and the right leg was biopsied with hollow needle(control group).After modeling for 14 days,X-ray examination was performed around the puncture holes and all rabbits were killed.The expression levels of PCNA and CD34 in soft tissues around the puncture hole were detected by enzyme-linked immunosorbent assay(ELISA).Results:By the end of the experiment,a total of three rabbits had died,and 27 rabbits were eventually included in the study.Tumor cells were detected in all the intramedullary specimens obtained by puncture biopsy.On the 14 th day after modeling,X-ray showed that the occurrence rate of periosteal reaction and extraosseous high density shadow around the puncture hole was14.81%(4/27)in the experimental group and 40.74%(11/27)in the control group.the difference was statistically significant(P<0.05).The pathological results of soft tissue around the puncture hole showed that the metastasis rate of tumor cells in the experimental group was 29.63%(8 / 27)and that in the control group was 100%(27 / 27),the difference was statistically significant(P < 0.05).The results of ELISA showed that the expression levels of PCNA and CD34 in the experimental group were significantly lower than those in the control group(P < 0.05).Conclusion:(1)Both the modified closed biopsy technique and needle aspiration biopsy can provide sufficient biopsy tissue for the diagnosis of VX2 transplanted bone tumor in rabbits.(2)The improved closed biopsy technique has a certain application value in preventing local metastasis of tumor cells along the puncture channel.