Multicellular Factors Promote Cystic Fluid Synthesis By Choline Kinase Alpha In Adamantinomatous Craniopharyngioma

Craniopharyngioma(CP)is a benign non-neuroepithelial tumor of intracranial saddle area,which is divided into two main subtypes,Adamantinomatous Craniopharyngioma(ACP)and Papillary Craniopharyngioma(PCP).ACP can occur at all ages,but has two major peaks of incidence(5-15 and 45-60 years of age),and is predominantly cystic or cystic solid with or without calcification and lipid-rich cyst fluid.Although the WHO classification of craniopharyngioma is type 1,due to the location of the tumor and its proximity to important surrounding tissues(pituitary gland,optic cross,hypothalamus,etc.),the development of the tumor can progressively compress these structures and cause a series of clinical symptoms,mainly non-specific manifestations such as headache,vomiting,visual impairment and hypothalamic-pituitary dysfunction,and due to the high surgical difficulty and easy recurrence of craniopharyngioma,it can be clinically manifested as benign disease but malignant.During the development of ACP,the mechanical compression of the surrounding tissues depends on the size of the tumor cystic cavity,which is related to the amount of cystic fluid in the cystic cavity,while the formation of a large cystic cavity is the main cause of hypothalamic-pituitary dysfunction,visual impairment and obstruction of cerebrospinal fluid circulation.cause.Therefore,clarifying the source of cystic fluid in the cystic cavity of ACP and the factors affecting its synthesis would be helpful to resolve or relieve some of the compression symptoms caused by the tumor.In this study,we analyzed the main components of ACP cyst fluid and found that Phosphatidylcholine(PC)is the main lipid component of cyst fluid,and Choline Kinase alpha(CK-α),a key enzyme for PC synthesis,has been found to promote tumor development in various tumors,including hepatocellular carcinoma.In ACP,we found that CK-α was mainly expressed in the tumor epithelium,and the correlation analysis of CK-α expression in ACP tissues with the corresponding patient’s cyst fluid content pointed out a good positive correlation between then two(Vcyst compared to DABscore:p<0.001,r=0.7785;Vcyst compared to WBCK-αEx:p<0.001,r=0.8488),together suggesting that the synthesis of ACP cyst fluid may be dependent on CK-α expression in the tumor epithelium.In vitro interference of CK-αexpression by SiRNA or the use of an inhibitor of this enzyme(MN58b)was effective in reducing PC synthesis in ACP cells along with a reduction in cell proliferation and migration.To investigate the factors affecting CK-α expression in ACP tumors,we found a large number of pro-inflammatory microglia infiltrating around the tumor and the presence of tumor-associated senescent secretory phenotype(SASP)based on previous studies and histopathological observations of ACP,and combined with the fact that CK-α expression is susceptible to multiple factors in vitro and in vivo,we induced the in vitro activation of cultured microglia and tumor We found that the above factors(M1-type microglia activation and tumor-associated senescent cells)could promote CK-α expression in ACP cells and lead to increased PC synthesis and enhanced cell proliferation and migration ability,thus suggesting that M1-type activated microglia and tumor-associated senescent cells in tumors could promote CK-α expression in tumor-associated cystic fluid by inducing CK-α expression in tumor cells.This suggests that M1-activated microglia and tumor-associated senescent cells can promote the synthesis of tumor-associated cyst fluid and the development of tumor cells(proliferation and migration)by inducing the expression of CK-α in tumor cells.The mechanism of senescence in tumor-associated senescent cells is still unknown and may be triggered by exon 3 mutations in the CTNNB1 gene,so we will not explore the study in this paper.However,the possible factors for M1-type activation of tumor microglia are to be explored,and we learned that both tumor-associated senescent cells and tumor-associated cyst fluid can induce microglia activation in in vitro experiments by combining the tumor characteristics of ACP.Thus,we concluded that in ACP,in addition to tumor-associated senescent cells or microglia M1-type activation can induce CK-α expression in tumor cells,tumor-associated senescent cells and cyst fluid can also play an indirect role in promoting CK-α expression in tumor cells by inducing microglia M1-type activation,leading to increased cyst fluid synthesis and promoting tumor progression.Thus,the aim of this study was to identify the possible sources of cyst fluid in ACP and the factors affecting its synthesis,and to explore the possibility of intervening in ACP cyst fluid synthesis or reducing or even eliminating ACP cyst fluid.