Expression of cell adhesion molecule CD44 in gastric adenocarcinoma and its prognostic importance

AIM: To evaluate the relation of cluster of differentiation 44 (CD44) expression with clinicopathological features of gastric adenocarcinoma, and also its effect on prognosis with an emphasis on the differences between intestinal and diffuse types. METHODS: From 2000 to 2006, 100 patients with gastric adenocarcinoma, who had undergone total or subtotal gastrectomy without any prior treatment, were studied. Haematoxylin & eosin (HE) staining was used for histological evaluation, including the type (Lauren's classifi cation) and grading of the tumor. The expression of CD44 in the gastric adenocarcinoma mucosa and the adjacent mucosa were determined by immunohistochemistry. The survival analysis was obtained using the Kaplan-Meier test. RESULTS: Of 100 patients, 74 (74%) patients were male. The tumors were categorized as intestinal type (78%) or diffuse type (22%). Sixty-five percent of patients were CD44-positive. CD44 expression was not detected in normal gastric mucosa. Rather, CD44 was more commonly expressed in the intestinal subtype (P = 0.002). A signifi cant relation was seen between the grade of tumor and the expression of CD44 (P = 0.014). The survival analysis showed a poor prognosis of patients with CD44-positive tumors (P = 0.008); and this was more prominent in the intestinal (P = 0.001) rather than diffuse type. CONCLUSION: Cell adhesion molecule CD44 is highly expressed in gastric adenocarcinoma. CD44 expression is correlated with a poor prognosis in patients with the intestinal type of gastric adenocarcinoma. CD44 can, therefore, be utilized as a prognostic marker for this group of patients.

Extraction, detection, and profiling of serum biomarkers using designed Fe3O4@SiO2@HA core-shell particles

Serum biomarkers in the form of proteins （e.g. cluster of differentiation-44 （CD44）） have been demonstrated to have high clinical sensitivity and specificity for disease diagnosis and prognosis. Owing to the high sample complexity and low molecular abundance in serum, the detection and profiling of biomarkers rely on efficient extraction by materials and devices, mostly using immunoassays via antibody-antigen recognition. Antibody-free approaches are promising and need to be developed for real-case applications in serum to address the limitations of antibody-based techniques in terms of robustness, expense, and throughput. In this work, we demonstrated a novel approach using hyaluronic acid （HA）-modified materials/devices for the extraction, detection, and profiling of serum biomarkers via ligand-protein interactions. We constructed Fe304@SiOa@HA particles with different sizes through layer-by-layer assembly and for the first time applied HA-functionalized particles in the facile extraction and sequence identification of CD44 in serum by mass spectrometry. We also first validated HA-CD44 binding through electrochemical sensing using HA- modified electrodes in both standard solutions and diluted serum samples, achieving a detection limit of -0.6 ng/mL and a linear response range from I ng/mL to 10 ~tg/mL. Furthermore, we performed profiling of HA-binding serum proteome, providing a new preliminary benchmark for the construction of future databases, and we investigated selected surface chemistries of particles for the capture of proteins in serum. Our work not only resulted in the development of a platform technology for CD44 extraction/detection and HA-binding proteome identification, but also guided the design of ligand affinity-based approaches for antibody-free analysis of serum biomarkers towards diagnostic applications.

LncRNA AFAP1-AS1/miR-27b-3p/VEGF-C axis modulates stemness characteristics in cervical cancer cells

Background:Long non-coding RNA(lncRNA)actin filament-associated protein 1 antisense RNA 1(AFAP1-AS1)functions as a competing endogenous RNA to regulate target genes expression by sponging microRNAs(miRs)to play cancer-promoting roles in cancer stem cells.However,the regulatory mechanism of AFAP1-AS1 in cervical cancer(CC)stem cells is unknown.The present study aimed to provide a new therapeutic target for the clinical treatment of CC.Methods:Hyaluronic acid receptor cluster of differentiation 44 variant exon 6(CD44v6)(+)CC cells were isolated by flow cytometry(FCM).Small interfering RNAs of AFAP1-AS1(siAFAP1-AS1)were transfected into the(CD44v6)(+)cells.The levels of AFAP1-AS1 were measured by quantitative real-time PCR(qRT-PCR).Sphere formation assay,cell cycle analysis,and Western blotting were used to detect the effect of siAFAP1-AS1.RNA pull-down and luciferase reporter assay were used to verify the relationship between miR-27b-3p and AFAP1-AS1 or vascular endothelial growth factor(VEGF)-C.Results:CD44v6(+)CCcells had remarkable stemness and a high level ofAFAP1-AS1.However,AFAP1-AS1knockdownwithsiAFAP1-AS1suppressed the cell cycle transitionofG(1)/S phase and inhibited self-renewal ofCD44v6(+)CCcells,the levels of the stemnessmarkers octamer-binding transcription factor 4(OCT4),osteopontin(OPN),and cluster of differentiation 133(CD133),and the epithelialmesenchymal transition(EMT)-related proteins Twist1,matrix metalloprotease(MMP)-9,and VEGF-C.In the mechanism study,miR-27b-3p/VEGF-C signaling was demonstrated to be a key downstream of AFAP1-AS1 in the CD44v6(+)CC cells.Conclusions:LncRNA AFAP1-AS1 knockdown inhibits the CC cell stemness by upregulating miR-27b-3p to suppress VEGF-C.