CD44v5 domain regulates crosstalk between TNBC cells and tumor-associated macrophages by enhancing the IL-4R/STAT3 axis.

Triple-negative breast cancer (TNBC) has greater infiltration of M2-like macrophages (TAMs), which enhances cancer cell invasion and leads to a poor prognosis. TNBC progression is mediated by both tumor cells and the tumor microenvironment (TME). Here we elucidate the mechanism of the interaction between TNBC cells and TAMs. In this study, we confirmed that CD44v5 is highly expressed in TNBC, which drives TNBC cell metastasis and promotes TAM polarization by co-localizing with IL4Rα and inhibiting its internalization and degradation, thereby promoting activation of the STAT3/IL6 signaling axis. At the same time, TAMs also facilitate TNBC cell metastasis by secreting IL-4, IL-6, and other cytokines, in which the IL-4/IL-4R/STAT3/IL-6 signaling axis plays the same role for TNBC cells responding to TAMs. Moreover, we found that the above progress could be suppressed when the CD44v5 domain was blocked. We demonstrated that the CD44v5/IL-4R/STAT3/IL-6 signaling pathway plays a key role in TNBC cell metastasis, and in TNBC cells inducing TAM polarization and responding to TAMs, promoting metastasis. Collectively, we suggest that the CD44v5 domain may be a promising target for regulating the TME of TNBC as well as treating TNBC.

CD44 v5 domain inhibition represses the polarization of Th2 cells by interfering with the IL-4/IL-4R signaling pathway.

The balance between T helper type 1 (Th1) and T helper type 2 (Th2) cells is critical for both innate and acquired immune reactions. However, the precise mechanisms of T helper-cell differentiation remain unclear. As an important T-cell activation molecule, CD44 participates in the differentiation of Th1 and Th2 cells. We demonstrated that CD44 variant exon v5 (CD44 v5) is highly expressed by induced human Th2 cells. To investigate the role of the CD44 v5 domain in Th2 cell differentiation, we treated human CD4+ T cells with anti-CD44v5 antibody and observed that the levels of phosphorylated STAT6 and GATA3 and the secretion of interleukin-4 (IL-4) were significantly decreased after the treatment. We also further found that the inhibition of Th2 differentiation was caused by the degradation of the alpha chain of IL-4 receptor (IL-4Rα), the CD44 v5 domain colocalized with IL-4Rα on cell surface and the degradation of IL-4Rα increased after CD44 v5 domain blocking or ablating. Our results indicated that CD44v5 antibody treatment interrupted the interaction between CD44 v5 domain and IL-4Rα, but the CD44 v5 domain blockage would not spoil the colocalization between IL-4R expression and T-cell receptor and the immunological synapse formation; similar results were also found in CD44v5-deficient CD4+ T cells. In conclusion, we revealed the function of the CD44 v5 domain in Th2 cell differentiation; blocking or ablating the CD44 v5 domain could accelerate IL-4Rα degradation and then induce the Th2 cell inhibition.

Detection the CD44v5 in serum for screening ESCC through ELISA / 实用医学杂志

Objective To detect the expression of CD44v5 in esophageal squamous carcinoma (ESCC) and analyze its relationship with clinical pathological features,so as to explore the value of detecting CD44v5 in serum for screening ESCC. Methods The CD44v5mRNA and protein in ESCC tissues and its corresponding adjacent non-carcinomatous tissues were detected by RT-PCR and Western-Blot. Enzyme-linked immunosorbent assay (ELISA) was applied to detect the protein in serum of 100 ESCC patients and 60 healthy subjects. Results (1)The expression of CD44v5 in esophageal squamous carcinoma tissues is higher than the tissue adjacent to carcinoma, and CD44v5 expression in different TNM stages, invasion depth, presence of lymph node metastasis and differentiation is with statistical differences(P < 0.05). (2)CD44v5 proteins in patients with ESCC (31.308 ± 10.123) μg/L is higher than healthy subjects (19.364 ± 1.680) μg/L, the difference is statistically significant (P < 0.01). (3)In the trial of using ELISA method to detect CD44v5 content in serum in the diagnosis of ESCC, the area under the ROC curve is 0.865. If the healthy subjects' serum content of the upper limit of 95%confidence interval was taken as a positive judgment standard, the diagnosis effect: sensitivity is 91.0%and speciality is 60.0%. Conclusion The expression of CD44v5 was related to the occurrence and lymph node metastasis of ESCC. Using ELISA method to detect the contents of CD44v5 proteins in serum, with a high sensitivity, can be used to screen ESCC.

Isolation and detection of CK17~+,CD44v5~+ and Bcrp1~+ cells in HeLa cell line of cervical carinoma / 吉林大学学报(医学版)

Objective To identify and isolate the CK17+,CD44v5+ and Bcrp1+ cells in HeLa cells,and investigate the relationship between them and select cervical cancer stem cell markers.Methods Flow cytometry was used to identify and isolate the CK17+,CD44v5+ and Bcrp1+ cells in HeLa cells;after isolation,the expressions of CK17 and CD44v5 in Bcrp1+ and Bcrp1-phenotype HeLa cells were measured by immunocytochemistry.Results HeLa cells contained 11% Bcrp1+ cells,0.7% CK17+ cells and 0.1%CD44v5+ cells.Bcrp1+ HeLa cells contained CK17+ and CD44v5+ HeLa cells,but the Bcrp1-Hela cells did not(P

PROLIFERATION OF CERVICAL RESERVE CELLS AND IMMUNOHISTOCHEMICAL STUDY OF CD44v5 / 解剖学报

Objective Cervical reserve cells are the maternal cells of cervical neoplasia. It's proliferation and origin were studied. Methods The pathological morphology of cervical reserve cell proliferating was observed by light microscopy in 238 cases of cervical benign diseases; Immunohistochemical technology of CD44v5 was used to inspect the expression of cervical reserve cells in 54 cases. Results and Conclusion 1.Reserve cell proliferation was common in most cases of cervical benign diseases and it was originated from stroma; 2 The proliferating reserve cells were composed of four types:large cells, small cells, clear cells and spindle cells; 3The expression of CD44v5 in reserve cells showed 100% strongly positive. The cells proliferation was common in begin diseases of cervix; Reserve cells possibly were originated from stroma.

Expression of CD_(44)V_5 and nm23-H_1 gene in esophageal cancer / 中国癌症杂志

Purpose:To study the expression of CD 44 V 5 and Nm23 H 1 gene products and their significance in esophageal cancer patients.Methods:The expression of CD 44 V 5 and Nm23 H 1 in 85 cases of formalin fixed, paraffin embedded specimens of esophageal cancer were measured by immunohistochemistry S P method. Fifty cases were followed up for 3 years after operation.Results:①The positive expression rate of CD 44 V 5 and Nm23 H 1 was 61.2% 、57 6%, respectively in esophageal cancer.②Overexpression of CD 44 V 5 gene products were closely related with the invasive extent , histopathologic classification , TNM stage ,lymph node metastasis(LNM) and prognosis of Ec( P