SPHK1 Promotes Pancreatic Cancer Lymphangiogenesis Through the Activation of ERK in LECs.

Lymphatic metastasis is related to an unsatisfactory prognosis in pancreatic cancer. Sphingosine kinase 1 (SPHK1) is an oncogene in cancer. However, the potential effect of SPHK1 on the lymphangiogenesis of pancreatic cancer is little known. In this study, the expression level and role of SPHK1 in pancreatic cancer were evaluated to explore the underlying mechanism involved. The expression of SPHK1 and the lymphatic vessel density (LVD) in pancreatic cancer patient tissue were investigated by immunohistochemistry. The role of SPHK1 in lymphangiogenesis was verified in vitro. Elevated expression of SPHK1 was strongly related to high LVD in pancreatic cancer patient tissue. Silencing of SPHK1 in pancreatic cancer cells observably inhibited lymphangiogenesis. Furthermore, the downregulation of SPHK1 markedly attenuated the phosphorylation of extracellular signal-regulated kinase in lymphatic endothelial cells. This study revealed that SPHK1 might play a crucial role in pancreatic cancer lymphangiogenesis.

Construction of a ceRNA network to reveal a vascular invasion associated prognostic model in hepatocellular carcinoma.

The aim of this study is to explore the prognostic value of vascular invasion (VI) in hepatocellular carcinoma (HCC) by searching for competing endogenous RNAs (ceRNA) network and constructing a new prognostic model for HCC. The differentially expressed genes (DEGs) between HCC and normal tissues were identified from GEO and TCGA. StarBase and miRanda prediction tools were applied to construct a circRNA-miRNA-mRNA network. The DEGs between HCC with and without VI were also identified. Then, the hub genes were screened to build a prognostic risk score model through the method of least absolute shrinkage and selection operator. The prognostic ability of the model was assessed using the Kaplan-Meier method and Cox regression analysis. In result, there were 221 up-regulated and 47 down-regulated differentially expressed circRNAs (DEcircRNAs) in HCC compared with normal tissue. A circRNA-related ceRNA network was established, containing 11 DEcircRNAs, 12 DEmiRNAs, and 161 DEmRNAs. Meanwhile, another DEG analysis revealed 625 up-regulated and 123 down-regulated DEGs between HCC with and without VI, and then a protein-protein interaction (PPI) network was built based on 122 VI-related DEGs. From the intersection of DEGs within the PPI and ceRNA networks, we obtained seven hub genes to build a novel prognostic risk score model. HCC patients with high-risk scores had shorter survival time and presented more advanced T/N/M stages as well as VI occurrence. In conclusion a novel prognostic model based on seven VI-associated DEGs within a circRNA-related ceRNA network was constructed in this study, with great ability to predict the outcome of HCC patients.

Plasma Methylated SEPT9 as a Novel Biomarker for Predicting Liver Metastasis in Colorectal Cancer.

This study aimed to explore the role of plasma methylated SEPT9 (mSEPT9) in predicting liver metastasis (LM) in colorectal cancer (CRC) patients. The clinicopathological information of 115 consecutive CRC patients were collected. The differences of clinical characteristics and several biomarkers between CRC patients with LM and those with non-liver metastasis (NM) were analyzed. Multivariate logistic regression analysis was used to identify the risk factors for predicting LM in CRC patients. Receiver operating characteristic curve (ROC) analysis was applied to investigate the sensitivity and specificity of potential biomarkers in indicating the presence of LM in CRC. Compared with the CRC without LM, the levels of plasma mSEPT9 and carcinoembryonic antigen (CEA) were significantly increased in CRC with LM. Multivariate logistic regression analysis showed that plasma mSEPT9 was an independent risk factor for predicting LM in CRC. ROC curves showed that mSEPT9 and CEA could efficiently distinguish LM from NM in CRC. The area under the curve (AUC) of mSEPT9 was 0.850, which was slightly higher than that of CEA (0.842). The optimal cut-off value of mSEPT9 was 35.09 with a sensitivity of 81.82% and a specificity of 73.33%, both similar with that of CEA (sensitivity 87.27% and specificity 75.00%). In addition, the combination of mSEPT9 and CEA had a higher specificity than CEA alone (81.70% Vs 75.00%). Our findings suggest, for the first time, that plasma mSEPT9 might serve as a potential biomarker to predict LM in CRC, which deserves further in-depth study.

Oxidative stress following spinal cord injury: From molecular mechanisms to therapeutic targets.

Spinal cord injury (SCI) is a medical condition that results from severe trauma to the central nervous system; it imposes great psychological and economic burdens on affected patients and their families. The dynamic balance between reactive oxygen species (ROS) and antioxidants is essential for maintaining normal cellular physiological functions. As important intracellular signaling molecules, ROS regulate numerous physiological activities, including vascular reactivity and neuronal function. However, excessive ROS can cause damage to cellular macromolecules, including DNA, lipids, and proteins; this damage eventually leads to cell death. This review discusses the mechanisms of oxidative stress in SCI and describes some signaling pathways that regulate oxidative injury after injury, with the aim of providing guidance for the development of novel SCI treatment strategies.

CEACAM1 Is a Prognostic Biomarker and Correlated with Immune Cell Infiltration in Clear Cell Renal Cell Carcinoma.

Background: CEACAM1 has been shown to be aberrantly expressed in a variety of tumors, and modulation of CEACAM1-related signaling pathways has been suggested as a novel approach for cancer immunotherapy in recent years. However, its role in clear cell renal cell carcinoma (ccRCC) is unclear. Methods: The relationship between CEACAM1 and ccRCC was demonstrated based on data from TCGA, GEO, and HPA databases. And the relationship between clinicopathological features and CEACAM1 expression was also assessed. Survival curve analysis was performed to analyze the prognostic relationship between CEACAM1 expression and ccRCC. Protein interaction network analysis was used to analyze the relationship between CEACAM1 and microenvironment-related proteins. In addition, the immunomodulatory role of CEACAM1 in ccRCC was assessed by analyzing CEACAM1 and immune cell infiltration. Results: The expression of CEACAM1 was lower in ccRCC tissues than in adjacent normal tissues, and its expression level was negatively correlated with tumor size status (P < 0.001), metastasis status (P = 0.009), pathological stage (P = 0.002), gender (P < 0.001), histological grade (P < 0.001), and primary therapy outcome (P = 0.045) of ccRCC. Survival curve analysis showed that ccRCC patients with lower CEACAM1 expression exhibited shorter overall survival (P < 0.001), and CEACAM1 interacted with microenvironmental molecules such as fibronectin and integrins. Furthermore, immune infiltration analysis showed that CEACAM1 expression correlated with CD8+ and CD4+ T cells, macrophage, neutrophil, and dendritic cell infiltration in ccRCC. Conclusions: CEACAM1 expression correlates with progression, prognosis, and immune cell infiltration in ccRCC patients, and it may be a promising prognostic biomarker and therapeutic target for ccRCC.

Upregulated TUBG1 expression is correlated with poor prognosis in hepatocellular carcinoma.

Background: Hepatocellular carcinoma (HCC) development is a complex pathological process. Tubulin gamma 1 (TUBG1) plays an oncogenic role in several human cancers; however, its functional role in HCC tumorigenesis remains unknown. Methods: Herein we first evaluated the gene expression levels of TUBG1 in HCC using data from The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis databases. We then elucidated the association between TUBG1 gene expression levels and survival rates of patients with HCC. Cell cycle, proliferation, transwell migration, and matrigel invasion assays were used to study the effects of TUBG1 on the malignant phenotypes of HCC cells. Results: Based on the data obtained from the aforementioned databases and our in vitro experiments, TUBG1 was found to be overexpressed in HCC and patients with high TUBG1 expression levels showed a remarkably poor overall survival rate. In addition, the expression of TUBG1 significantly promoted the malignant phenotypes of HCC cells in vitro. Gene ontology term enrichment analysis revealed that co-regulated genes were enriched in biological processes mainly involved in chromosome segregation, chromosomal region, and chromatin binding; moreover, Kyoto Encyclopedia of Genes and Genome pathway analysis showed that they were mainly involved in cell cycle, oocyte meiosis, platinum drug resistance, and the p53 signaling pathway. Conclusions: We report that TUBG1 is an important oncogene in HCC. It promotes HCC progression and may serve as a potential prognostic biomarker for HCC. Future studies are warranted to unveil molecular biological mechanisms underlying TUBG1 carcinogenesis.

Determining the Optimal Cut-Off Values of Serum E2 and FSH for Evaluating the Menopausal Status of Breast Cancer Patients in a Southern Chinese Population.

Background: Chemotherapy-induced amenorrhea (CIA) is one of universal phenomena in breast cancer (BC) patients, and it causes difficulties in evaluating the actual menopausal status which is important for the oncologists to choose appropriate treatment. Currently, serum estradiol (E2) and follicle-stimulating hormone (FSH) levels are the most commonly used clinical parameters for the assessment of menopausal status in BC patients. However, the optimal cut-off points of serum E2 and FSH have little been explored in southern Chinese population. Objective: This study is aimed to determine the optimal cut-off values of the serum E2 and FSH levels for evaluating the menopausal status of BC patients in a southern Chinese population. Methods: A retrospective analysis was done among a total of 206 patients with BC from a southern Chinese area. The data of serum E2, FSH, and luteinizing hormone (LH) levels were collected and analyzed for the comparison purpose. The receiver-operating curve (ROC) was generated to assess the specificity and sensitivity of the three biomarkers in discriminating the menopausal status of BC patients. The optimal cut-off values were determined according to the Youden index and then compared with the recommended reference values by the Chinese Anti-cancer Association (CACA) and those recommended by the manufacturers. Results: The areas under the ROC curves (AUCs) of E2, FSH, and LH were 0.846 (95% CI: 0.790-0.903), 0.781 (95% CI: 0.714-0.847) and 0.608 (95% CI: 0.526-0.690), respectively. The optimal cut-off values were 130.0 pg/mL for E2, 23.325 IU/L for FSH, and 11.625 IU/L for LH with a maximum of the Youden index. When E2, FSH, and LH were used in combination for ROC analysis, the AUC increased to 0.847 (95% CI: 0.790-0.904), which was higher than that of any other biomarker alone. In this study, the sensitivity and specificity of E2 and FSH were 91.6% and 73.70% and 94.4% and 58.6%, respectively, in comparison with 85.0% and 75.80% and 76.6% and 65.7% according to the CACA-recommended cut-off points, or 92.5% and 68.7% and 96.3% and 53.5% according to the manufacturer recommended cut-off points. Conclusion: Considering the sensitivity and specificity of serum E2 and FSH for assessing the menopausal status, the optimal cut-off values determined in the present study were similar to the manufacturer's recommendations, but obviously superior to the cut-off points suggested by CACA. These cut-off points calculated in this study seem to be valuable in southern Chinese population and might be used by clinicians to make a correct medical decision for BC patients who would benefit from endocrine therapy of aromatase inhibitor (AI).

MiR-34a-5p Negatively Regulates Oxidative Stress on Lens Epithelial Cells by Silencing GPX3 - A Novel Target.

PURPOSE: MiR-34a-5p is reported to be related with age-related nuclear cataract. This study investigated the mechanism of miR-34a-5p in the regulation of oxidative stress on lens epithelial cells. METHODS: The three candidate miRNAs were screened by CCK-8 assays after transfection of mimics or inhibitor in H2O2-treated HLE-B3 cells. The apoptosis, ROS level and GPX activity of HLE-B3 cells transfected with miR-34a-5p mimics or inhibitor were analysed by flow cytometry, cellular ROS and GPX activity test. The target genes of miR-34a-5p were predicted by proteomic and bioinformatic analysis. The relationship between miR-34a-5p and GPX3 were internally validated by qRT-PCR and Western blot and externally verified by dual-luciferase reporter assay. The effect of miR-34a-5p-GPX3 axis on regulation of oxidative stress in HLE-B3 cells were conducted by overexpression of GPX3 and tested by flow cytometry analysis, cellular ROS and GPX detection. RESULTS: The viability of H2O2-treated HLE-B3 cells were weakened by up-regulated miR-34a-5p. Cell apoptosis and oxidative damage were also induced by overexpression of miR-34a-5p. GPX3 and SRC were identified as target genes of miR-34a-5p by combined analysis of proteomic and bioinformatics, while GPX3 was selected for further research for its connection with anti-oxidation. Western blot and qRT-PCR tests proved that GPX3 is negatively regulated by miR-34a-5p. Dual-luciferase reporter assay verified that GPX3 is the direct target of miR-34a-5p. The increased oxidative stress induced by transfection of miR-34a-5p mimics in H2O2-treated HLE-B3 cells was attenuated by overexpression of GPX3. CONCLUSIONS: MiR-34a-5p is a negative regulator of oxidative stress on lens epithelial cells and the mechanism is by silencing the expression of GPX3. These data suggest that miR-34a-5p may be a potential novel therapeutic target for the prevention and treatment of age-related cataract.

Corrigendum: Upregulated LINC01667 Expression Is Correlated With Poor Prognosis in Hepatocellular Carcinoma.

[This corrects the article DOI: 10.3389/fonc.2021.650173.].

Upregulated LINC01667 Expression Is Correlated With Poor Prognosis in Hepatocellular Carcinoma.

The development of hepatocellular carcinoma (HCC) is a complex pathological process. Long intergenic non-protein-coding RNA 1667 (LINC01667, also known as MGC38584) plays an oncogenic role in several human cancers; however, its functional role in HCC tumorigenesis remains unknown. Here, we first evaluated the gene expression levels of LINC01667 in HCC using data from The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis (GEPIA) databases. We then elucidated the association between LINC01667 gene expression levels and the survival rates of patients with HCC. We detected the effect of LINC01667 on the malignant phenotypes (cell proliferation, migration, invasion and apoptosis etc.) and the MAPK and PI3K/AKT/mTOR signaling pathways of HepG2, SMMC-7721 and HUH7 cells. We also analyzed the sensitivity of HepG2, SMMC-7721 and HUH7 with different expression levels of LINC01667 to anti-HCC drugs in vitro. Based on data from the aforementioned databases and our experiments in vitro, we found that LINC01667 was overexpressed in HCC, and that patients with high LINC01667 levels had a remarkably poor overall survival rate. In addition, inhibition of LINC01667 expression suppressed the proliferation, migration and invasion of HepG2 and SMMC-7721 cells and promoted their apoptosis in vitro. In contrast, overexpression of LINC01667 promoted the proliferation, migration and invasion of HUH7 cells and suppressed their apoptosis in vitro. ChIRP-seq (chromatin isolation by RNA purification) showed that LINC01667 bound to MEG3, and downregulated the expression of MEG3. In addition, western blotting showed that LINC01667 could activate the NF-κB pathway to promote cancer progression. In conclusion, we report that LINC01667 is an important oncogene in HCC and may be used as a potential diagnostic and prognostic biomarker of HCC.

Increased SPHK1 and HAS2 Expressions Correlate to Poor Prognosis in Pancreatic Cancer.

OBJECTIVE: SPHK1 and HAS2 have been reported to play important roles in tumorigenesis and development. However, their expression and prognostic value in pancreatic cancer (PC) remain unclear. This study is aimed at investigating the expression of SPHK1 and HAS2 on the prognosis of pancreatic cancer. MATERIALS AND METHODS: The expression of SPHK1 and HAS2 in pancreatic cancer tissues was analyzed through TCGA and GTEx databases and validated by qRT-PCR and Western blot in pancreatic cancer cell lines. χ 2 test was used to explore the correlation of the SPHK1 and HAS2 expressions with clinical characteristics. Kaplan-Meier survival analysis and ROC curve were used to evaluate the prognostic and diagnostic roles of SPHK1 and HAS2 in pancreatic cancer. Additionally, Spearman correlation analysis was applied to assess the correlation between the SPHK1 and HAS2 in pancreatic cancer. GO analysis and KEGG analysis were applied to explore the possible signaling pathway that SPHK1 and HAS2 coregulated genes mediated. RESULTS: The expression of SPHK1 and HAS2 was markedly upregulated in pancreatic cancer tissue and cell lines, respectively. Furthermore, there was a significant positive correlation between SPHK1 and HAS2 expressions. ROC curves showed that SPHK1 combine with HAS2 has good diagnostic value in pancreatic cancer patients with 85% sensitivity and 99.4% specificity. Kaplan-Meier analysis showed that increased expression of SPHK1 and HAS2 was significantly associated with short overall survival (OS) of pancreatic cancer patients. GO and KEGG results revealed that SPHK1 and HAS2 mainly involved cell proliferation and invasion mediated by extracellular matrix- (ECM-) receptor interaction, focal adhesion, and PI3K-AKT signaling pathways. CONCLUSIONS: Overexpression of SPHK1 and HAS2 could be important markers for the prognosis of pancreatic cancer.

Serum ProGRP as a novel biomarker of bone metastasis in prostate cancer.

BACKGROUND: The prognosis of prostate cancer (PCa) is related to tumor metastasis, among which 80% were bone metastasis. In this study, we investigated the correlation between diverse clinical factors and bone metastasis in PCa patients and identified potential biomarkers of bone metastasis in PCa patients. METHODS: The clinical data of 150 PCa patients were reviewed consecutively from January 2015 to March 2020 in this study. The relationships between clinical characteristics, serum biomarkers and bone metastasis in PCa patients were analyzed, respectively. Multivariate logistic regression analysis was applied to identify potential markers of bone metastasis in prostate cancer. Receiver operating characteristic (ROC) curve was used to explore the diagnostic values of potential biomarkers. RESULTS: Compared with the PCa patients without bone metastasis, the serum levels of CA-125, T-PSA, F-PSA, CYFRA21-1 and ProGRP were significantly elevated in PCa patients with bone metastasis. Multivariate logistic regression analysis showed that T-PSA (OR 1.014, P = 0.021), F-PSA (OR 1.124, P = 0.016) and Pro-gastrin-releasing peptide (ProGRP) (OR 1.057, P = 0.026) were significantly associated with the bone metastasis of PCa patients. ROC curves indicated that T-PSA, F-PSA and ProGRP could effectively discriminate bone metastasis from non-bone metastasis PCa patients, and the AUCs (area under the curves) were 0.885, 0.919 and 0.752, respectively. According to the Youden index, the cut-off values of T-PSA, F-PSA and ProGRP were defined as 56.50 ng/ml, 6.96 ng/ml and 31.60 pg/ml, respectively. T-PSA, F-PSA and ProGRP produced a sensitivity of 78.30%, 81.70% and 61.70%, a specificity of 93.30%, 88.90% and 82.20%, respectively. The AUC for the combination of T-PSA, F-PSA with ProGRP was 0.941 with 90.00% sensitivity, much better than that of any single biomarker or two biomarkers combinate. CONCLUSIONS: Serum ProGRP might be a potential tumor marker of bone metastasis in prostate cancer, which may contribute to the early diagnosis of bone metastasis when used alone or in combination with other commonly used biomarkers.

Long noncoding RNA OR3A4 promotes the proliferation and invasion of osteosarcoma cells by sponging miR-1227-5p.

BACKGROUND: Long noncoding RNAs (lncRNAs) have been identified as key players in promoting tumourigenesis in osteosarcoma. LncRNA OR3A4 (OR3A4) has been reported as an oncogene in a number of tumours. However, the clinical value of OR3A4 in osteosarcoma and the role of OR3A4 in osteosarcoma progression are still unknown. METHODS: The expression levels of OR3A4 in the tumour tissue of osteosarcoma patients and osteosarcoma cell lines were detected by RT-PCR. Kaplan-Meier analysis and log-rank test were performed to evaluate the relationship between the level of OR3A4 expression and the prognosis of osteosarcoma patients. We investigated the association between the tissue expression levels of OR3A4 and different clinicopathological characteristics of osteosarcoma patients by χ2 tests. Bioinformatic databases and luciferase reporter assays were used to predict and validate the target microRNA of OR3A4. Finally, the role of OR3A4 in the proliferation and invasion of osteosarcoma cells was tested by MTT and Transwell assays, respectively. RESULTS: We observed that the expression level of OR3A4 was upregulated in the tumour tissue of osteosarcoma patients (p < 0.001) and osteosarcoma cell lines (p < 0.01) compared with the normal adjacent tissue and a normal human foetal osteoblastic cell line, respectively. The survival curve revealed that patients with high expression levels of OR3A4 had lower overall survival. Increased OR3A4 expression in osteosarcoma patients was associated with distant metastasis (p = 0.02) and advanced clinical stage (p < 0.001). In addition, bioinformatics analysis and luciferase reporter assays verified the complementary binding between OR3A4 and miR-1227-5p. Furthermore, we found that OR3A4 acted as a miR-1227-5p "sponge" to modulate osteosarcoma cell proliferation and invasion via downregulation of miR-1227-5p. CONCLUSION: OR3A4 promotes osteosarcoma cell proliferation and invasion by sponging miR-1227-5p, which might be related to the metastasis of osteosarcoma and could be used as a potential prognostic biomarker and therapeutic target in osteosarcoma.

Identification of H2O2 induced oxidative stress associated microRNAs in HLE-B3 cells and their clinical relevance to the progression of age-related nuclear cataract.

BACKGROUND: This study is aimed to screen out the microRNAs (miRNAs) associated with H2O2 induced oxidative stress in human lens epithelial B3 (HLE-B3) cell lines and investigate their relations with the progression of age-related nuclear cataract. METHODS: H2O2 was used to induce oxidative stress in HLE-B3 cells. A genome-wide expression profiling of miRNAs in HLE-B3 cells was performed to select the differentially expressed miRNAs before and after H2O2 treatment. The selected miRNAs were validated by RT-PCR and fluorescence in situ hybridization (FISH). Clinical specimens were divided into three groups according to the Lens Opacities Classification System III (LOCSIII) and the expression levels of the selected miRNAs were tested by RT-PCR in the three groups. Bioinformatics analyses were applied to predict the target genes of the miRNA hits and construct the miRNA regulatory network. The expression level of MAPK14 was analyzed by Western blot. RESULTS: The H2O2 induced oxidative stress model of HLE-B3 cells was established. Nineteen upregulated and 30 downregulated miRNAs were identified as differentially expressed miRNAs. Seven of the total 49 were validated in the cell model. RT-PCR of the clinical samples showed that the expression levels of miR-34a-5p, miR-630 and miR-335-3p were closely related with the severity of nuclear opacity. The images taken from FISH confirmed the results of RT-PCR. There were 172 target genes of the three miRNAs clustered in the category of response to stress. The regulatory network demonstrated that 23 target genes were co-regulated by multiple miRNAs. MAPK14 was the target gene of three miRNAs and the result were verified by Western blot. CONCLUSION: Up-regulation of miR-34a-5p and miR-630 and down-regulation of miR-335-3p are related with the progression of age-related nuclear cataract and the underlying mechanism awaits further functional research to reveal.

The cooperative role of S1P3 with LYVE-1 in LMW-HA-induced lymphangiogenesis.

Lymphangiogenesis, the formation of new lymph vessels, plays a significant role in the development and metastasis of various cancers. We and others have demonstrated that low molecular weight hyaluronan (LMW-HA) promotes lymphangiogenesis. However, the underlying mechanisms are poorly defined. In this study, using immunofluorescence and co-immunoprecipitation, we found that LMW-HA increased the colocalization of lymphatic vessel endothelial HA receptor (LYVE-1) and sphingosine 1-phosphate receptor (S1P3) at the cell surface. Silencing of either LYVE-1 or S1P3 decreased LMW-HA-mediated tube formation in lymphatic endothelial cells (LECs). Furthermore, silencing of either LYVE-1 or S1P3 significantly inhibited LMW-HA-induced tyrosine phosphorylation of Src kinase and extracellular signal-regulated kinase (ERK1/2). In summary, these results suggest that S1P3 and LYVE-1 may cooperate to play a role in LMW-HA-mediated lymphangiogenesis. This interaction may provide a useful target for the intervention of lymphangiogenesis-associated tumor progression.

Hyaluroan-regulated lymphatic permeability through S1P receptors is crucial for cancer metastasis.

Disruption of cancer lymphatic vessel barrier function occurs has been reported to involve in cancer lymphatic metastasis. Hyaluronan (HA), a major glycosaminoglycan component of the extracellular matrix, is associated with cancer metastasis. We investigated the effect of high/low molecular weight hyaluronan (HMW-HA/LMW-HA) on regulation of barrier function and tight junctions in cancer lymphatic endothelial cell (LEC) monolayer. Results showed that LMW-HA increased the permeability of cancer LEC monolayers and induced disruption of Zonula Occludens-1 (ZO-1)-mediated intercellular tight junction and actin stress fiber formation. HMW-HA treatment decreased permeability in cancer LEC monolayers and cortical actin ring formation. As reported, sphingosine 1-phosphate (S1P) receptors are involved in vascular integrity. After silencing of lymphatic vessel endothelial hyaluronan receptor (LYVE-1), upregulation of S1P receptors (S1P1 and S1P3) induced by HMW-HA/LMW-HA were inhibited, respectively. With S1P3 silenced, the disruption of ZO-1 as well as stress fiber formation and the ROCK1/RhoA signaling pathway induced by LMW-HA was not observed in cancer LEC. These results suggested that S1P receptors may play an important role in HMW-HA-/LMW-HA-mediated regulation of cancer lymphatic vessel integrity, which might be the initial step of cancer lymphatic metastasis and a useful intervention of cancer progression.