Research On The Effects And Mechanisms Of Nimesulide And Oxaliplatin On Human Lung Cancer Xenograft In Nude Mice

Objective:Lung cancer is a malignant tumor. The treatment scheme oflung cancer is decided by lung cancer staging. Because of the atypicalincipient symptoms, lung cancer may have developed into an advanced stageat the moment of clinical diagnosis. Once the metastasis happens, it meansthat local treatment, such as surgical resection, is invalid. Therefore patientsneed systemic treatment, but the effect is often not satisfactory. So research onthe relationship between tumor metastasis and relative factors, perhaps, finds anew way to the early diagnosis of lung cancer.Hypoxia-inducible factor(HIF) is a heterodimer composed of HIF-1aand HIF-1β subunits. There is the oxygen-dependent degradationdomain(ODD) in HIF-1a subunit. In the presence of oxygen, HIF-1β subunitis relatively stable, whereas HIF-1a subunit binds to the von Hippel-Lindau(vHL) tumor suppressor protein, leading to the degradation of HIF-1a; Underconditions of hypoxia, HIF-1a subunit accumulates and binds to HIF-1βsubunit, thus forming the active HIF complex that initiates transcription byhypoxia response elements (HRE) on the target genes.Vascular endothelial growth factor receptor-3(VEGFR-3) belongs tocell surface tyrosine kinase receptors. VEGFR-3combined with its ligandvascular endothelial growth factor-C(VEGF-C) induces the functions oflymphatic endothelial cells, including proliferation, migration and lymphaticformation via the MEK/ERK and PI3/Akt pathways.Chemokine receptor7(CCR7) is a member of the CC chemokinereceptor family. It combined with its ligands CCL19,CCL21can induceintracellular actin polymerization, promoting the formationg of celledpseudopodia. And then metastasis is beginning.Nm23is a well-known tumor metastasis inhibition gene. Nm23-H1 belongs to a member of eight sununits. Its product is nucleoside-diphosphatekinase(NDPK) which affects the formation of phosphoric acid nucleoside.NDPK can affect G protein-mediated signaling pathways and microtubulespolymerization,which plays a crucial role of tumor cell proliferation,differentiation, invasion and metastasis.Nimesulide is one of the selective cyclooxygenase-2(COX-2) inhibitors.Compared with traditional COX-2inhibitors, it can almost inhibit the COX-2function, barely affecting COX-1. Experiments confirmed that Nimesulide notonly prevents tumor occurrence, but also repress tumor growth and metastasis.More importantly, it can enhance the effectiveness of chemotherapy andradiotherapy. Oaliplatin is the third generation of platinum chemotherapymedicine. It hardly induces kingey toxicty of cisplatin and marrow toxicty ofcarboplatin. This study is designed to evaluate the effects and mechanisms ofnimesulide combined with oxaliplatin on HIF-1a, CCR7, VEGFR-3andnm23-H1expressions in lung cancer xenograft on nude mice.Methods: Nude mice were randomly divided into four groups,6eachgroup: nimesulide-treated group, oxaliplatin-treated group, nimesulidecombined with oxaliplatin-treated group and control group. The human lungcancer A549cell suspension was injected subcutaneously in nude mice toestablish xenograft animal model. They were executed after administering30days respectively, cut transplanted tumor tissues which were used forimmunohistochemistry and RT-PCR detection of HIF-1a, VEGFR-3, CCR7ang nm23-H1expressions.Results: The integral optical density measured by image analysis systemcan reflect the expression strength of HIF-1a, VEGFR-3, CCR7and nm23-H1proteins in immunohistochemical staining sections. Compared with the controlgroup, statistical analysis showed that the expression levels of HIF-1a,VEGFR-3and CCR7proteins of nimesulide-treated group and nimesulidecombined with oxaliplatin-treated group were significantly reduced(respectively, P<0.05), thus nm23-H1protein increasing (P<0.05).Compared with the control group, statistical analysis showed that the expression levels of HIF-1a, VEGFR-3and nm23-H1proteins ofoxaliplatin-treated group were scarely changed(respectively, P>0.05), CCR7protein increasing(P<0.05). Compared with nimesulide-treated group,statistical analysis showed that the expression levels of HIF-1a, VEGFR-3andCCR7proteins of nimesulide combined with oxaliplatin-treated group werereduced (respectively, P<0.05), nm23-H1protein increasing (P<0.05).Pearson correlation analysis of the four factors showed the expression ofHIF-1a, VEGFR-3and nm23-H1proteins were significantlycorrelation(P<0.05,1>r>0or-1<r<0). But CCR7with HIF-1a, VEGFR-3andnm23-H1were not correlation(P>0.05)According to RT-PCR analysis of HIF-1a, VEGFR-3, CCR7andnm23-H1mRNA. Compared with the control group, statistical analysisshowed that the expression levels of HIF-1a, VEGFR-3and CCR7mRNA ofnimesulide-treated group and nimesulide combined with oxaliplatin-treatedgroup were significantly reduced (respectively, P<0.05), thusnm23-H1mRNA increasing (P<0.05). Compared with the control group,statistical analysis showed that the expression levels of HIF-1a, VEGFR-3,CCR7and nm23-H1mRNA of the oxaliplatin-treated group were scarelychanged(respectively, P>0.05). Compared with nimesulide-treated group,statistical analysis showed that the expression levels of HIF-1a,VEGFR-3andCCR7mRNA of nimesulide combined with oxaliplatin-treated group werereduced (respectively, P<0.05), nm23-H1mRNA increasing (P<0.05).Pearson correlation analysis of the four factors showed the expression ofHIF-1a, VEGFR-3, CCR7and nm23-H1mRNA were significantlycorrelation(P<0.05,1>r>0or-1<r<0).Conclusion: Using nimesulide alone or combined with oxaliplatin wasable to significantly inhibit the expression of HIF-1a, VEGFR-3and CCR7,enhancing the expression of nm23-H1. Oxaliplatin could increase theexpression of CCR7protein, hardly affecting CCR7mRNA, probably viapromoting the translation of CCR7gene or inhibiting the degradation of CCR7protein, causing protein collection. Combined with oxaliplatin, the nimesulide can enhance the effect of anyone drug against tumor.