Effect of the LPA-mediated CXCL12-CXCR4 axis in the tumor proliferation, migration and invasion of ovarian cancer cell lines

Plasma membrane SK2 channel activity regulates migration and chemosensitivity of high-grade serous ovarian cancer cells

No data are currently available on the functional role of small conductance Ca2+-activated K+ channels (SKCa) in ovarian cancer. Here, we characterized the role of SK2 (KCa2.2) in ovarian cancer cell migration and chemosensitivity. Using the selective non-cell-permeant SK2 inhibitor Lei-Dab7, we identified functional SK2 channels at the plasma membrane, regulating store-operated Ca2+ entry (SOCE) in both cell lines tested (COV504 and OVCAR3). Silencing KCNN2 with short interfering RNA (siRNA), or blocking SK2 activity with Lei-Dab7, decreased cell migration. The more robust effect of KCNN2 knockdown compared to Lei-Dab7 treatment suggested the involvement of functional intracellular SK2 channels in both cell lines. In cells treated with lysophosphatidic acid (LPA), an ovarian cancer biomarker of progression, SK2 channels are a key player of LPA pro-migratory activity but their role in SOCE is abolished. Concerning chemotherapy, SK2 inhibition increased chemoresistance to Taxol® and low KCNN2 mRNA expression was associated with the worst prognosis for progression-free survival in patients with serous ovarian cancer. The dual roles of SK2 mean that SK2 activators could be used as an adjuvant chemotherapy to potentiate treatment efficacy and SK2 inhibitors could be administrated as monotherapy to limit cancer cell dissemination.

The Autotaxin-LPA Axis Emerges as a Novel Regulator of Smooth Muscle Cell Phenotypic Modulation during Intimal Hyperplasia

Neointimal hyperplasia is characterized by a loss of the contractile phenotype of vascular smooth muscle cells (VSMCs). Our group has recently shown that VSMC proliferation and migration are mediated by lysophosphatidic acid (LPA) during restenosis, but the role of autotaxin (ATX; lysophospholipase D), which produces LPA, remains unclear. Endothelial denudation of the mouse carotid artery was performed to induce neointimal hyperplasia, and the extent of damage caused by the ATX-LPA axis was assessed in VSMCs. We observed the upregulation of ATX activity (p < 0.0002) in the injured carotid artery using an AR2 probe fluorescence assay. Further, the tissue carotid LPA levels were elevated 2.7-fold in carotid vessels, augmenting neointimal hyperplasia. We used an electrical cell-substrate impedance sensor (ECIS) to measure VSMC proliferation and migration. Treatment with an ATX inhibitor (PF8380) or LPA receptor inhibitor (Ki16425) attenuated VSMC proliferation (extracellular signal-regulated kinases) activity and migration in response to recombinant ATX. Indeed, PF8380 treatment rescued the aggravated post-wire injury neointima formation of carotid arteries. The upregulation of ATX following vessel injury leads to LPA production in VSMCs, favoring restenosis. Our observations suggest that inhibition of the ATX-LPA axis could be therapeutically targeted in restenosis to minimize VSMC phenotypic modulation and inflammation after vascular injury.

Lysophosphatidic Acid Signaling in Cancer Cells: What Makes LPA So Special?

Lysophosphatidic acid (LPA) refers to a family of simple phospholipids that act as ligands for G protein-coupled receptors. While LPA exerts effects throughout the body in normal physiological circumstances, its pathological role in cancer is of great interest from a therapeutic viewpoint. The numerous LPA receptors (LPARs) are coupled to a variety of G proteins, and more than one LPAR is typically expressed on any given cell. While the individual receptors signal through conventional GPCR pathways, LPA is particularly efficacious in stimulating cancer cell proliferation and migration. This review addresses the mechanistic aspects underlying these pro-tumorigenic effects. We provide examples of LPA signaling responses in various types of cancers, with an emphasis on those where roles have been identified for specific LPARs. While providing an overview of LPAR signaling, these examples also reveal gaps in our knowledge regarding the mechanisms of LPA action at the receptor level. The current understanding of the LPAR structure and the roles of LPAR interactions with other receptors are discussed. Overall, LPARs provide insight into the potential molecular mechanisms that underlie the ability of individual GPCRs (or combinations of GPCRs) to elicit a unique spectrum of responses from their agonist ligands. Further knowledge of these mechanisms will inform drug discovery, since GPCRs are promising therapeutic targets for cancer.

Role of lysophosphatidic acid and its receptors in health and disease: novel therapeutic strategies

Lysophosphatidic acid (LPA) is an abundant bioactive phospholipid, with multiple functions both in development and in pathological conditions. Here, we review the literature about the differential signaling of LPA through its specific receptors, which makes this lipid a versatile signaling molecule. This differential signaling is important for understanding how this molecule can have such diverse effects during central nervous system development and angiogenesis; and also, how it can act as a powerful mediator of pathological conditions, such as neuropathic pain, neurodegenerative diseases, and cancer progression. Ultimately, we review the preclinical and clinical uses of Autotaxin, LPA, and its receptors as therapeutic targets, approaching the most recent data of promising molecules modulating both LPA production and signaling. This review aims to summarize the most update knowledge about the mechanisms of LPA production and signaling in order to understand its biological functions in the central nervous system both in health and disease.

Emerging role of RNF2 in cancer: From bench to bedside

RNF2 (also known as ding, Ring1B or Ring2) is a member of the Ring finger protein family, which functions as E3 ubiquitin ligase for monoubiquitination of histone H2A at lysine 119 (H2AK119ub). RNF2 gene is located at the 1q25.3 site of human chromosome and the coding region is composed of 9 exons, encoding 336 amino acids in total. Many studies have demonstrated that overexpressed RNF2 was involved in the pathological progression of multiple cancers and has an impact on their clinical features. For instance, the upregulated expression level of RNF2 is positively correlated with the occurrence and progression of hepatocellular carcinoma, melanoma, prostate cancer, breast cancer, pancreatic cancer, gastric cancer, and bladder urothelial carcinoma, as well as with the radioresistance of lung cancer and chemoresistance of ovarian cancer. This review provides an up-to-date perspective on the relationship between RNF2 and several cancers and highlights recent studies on RNF2 regulation. In particular, the relevant cellular signaling pathways and potential clinical value of RNF2 in cancers are also discussed, suggesting its potential as an epigenetic biomarker and therapeutic target for these cancers.

Diverse Effects of Lysophosphatidic Acid Receptors on Ovarian Cancer Signaling Pathways

Lysophosphatidic acid (LPA) is a bioactive phospholipid with mitogenic and growth factor-like activities affecting cell invasion, cancer progression, and resistance. It is produced mainly by autotaxin and acts on six G-protein-coupled receptors, LPAR1-6. LPA has recently been implicated as a growth factor present in ascites of ovarian cancer patients. However, mitogenic pathways stimulated by LPA via its receptors may involve any novel, thus far uncharacterized, signaling pathway(s). Here we show that three LPA receptors are involved in tumor progression by activation of both the AKT and ERK signaling pathways. CRISPR-edited LPAR2 and LPAR3 knockouts have opposing effects on ERK activation, whereas LPAR6 is involved in the activation of AKT, affecting cell migration and invasion. Our study identifies specific molecular machinery triggered by LPA and its receptors that modulates tumor cells and can serve as therapeutic target in this malignancy.

Clinical Significance of Serum Chemokines in Esophageal Cancer

BACKGROUND The aim of this study was to detect the expression levels of chemokines (CX3CL1, CXCL-11, CXCL-12, CCL3, CCL4, and CCL20) in the serum of esophageal cancer patients and a normal control group, and to explore the correlations of those expression levels with the pathological type, progression, and metastasis of esophageal cancer. MATERIAL AND METHODS A total of 50 normal people and 50 untreated patients initially diagnosed with esophageal cancer (including 17 cases of non-metastatic esophageal cancer, 33 cases of metastatic esophageal cancer, 36 cases of esophageal squamous cell carcinoma and 14 cases of esophageal adenocarcinoma) were collected. The liquid chip (Luminex) technology was applied to detect the expression levels of the above-mentioned serum chemokines in the two groups. The results were analyzed using Statistical Product and Service Solution 20.0 software. RESULTS The expression levels of CX3CL1, CXCL-12, and CCL20 in esophageal cancer group were evidently higher than those in normal control group (P<0.001, P<0.001 and P=0.003, respectively). There were no statistically significant differences in chemokine expressions between metastatic esophageal cancer group and non-metastatic esophageal cancer group (P>0.05). The expression level of serum CCL4 in esophageal adenocarcinoma group was remarkably higher than that in esophageal squamous cell carcinoma group [18.45 (11.94) versus 13.37 (9.29), Z=-2.039, P=0.031]. In esophageal cancer group and normal control group, the serum CX3CL1 was positively correlated with CCL20 (r=0.649, P<0.001, r=0.758, P<0.001). CONCLUSIONS The expressions of serum CX3CL1, CXCL-12, and CCL20 are increased markedly in the patients, which may promote the occurrence, development and metastasis of esophageal cancer.

Overexpression of microRNA-195-5p reduces cisplatin resistance and angiogenesis in ovarian cancer by inhibiting the PSAT1-dependent GSK3β/β-catenin signaling pathway

Background

Ovarian cancer (OC) is one of the leading causes for cancer-related deaths among women. MicroRNAs (miRs) have been proved to be vital to the development and progression of OC. Hence, the study aims to evaluate the ability of miR-195-5p affecting cisplatin (DDP) resistance and angiogenesis in OC and the underlying mechanism.

Methods

MiRs that could target phosphoserine aminotransferase 1 (PSAT1), a differentially expressed gene in OC, were predicted by miRNA-mRNA prediction websites. The expression patterns of miR-195-5p in the OC tissues and cells were determined using RNA quantification assay. The role of miR-195-5p in OC was evaluated by determining DDP resistance, apoptosis and angiogenesis of OC cells after up-regulating or down-regulating miR-195-5p or PSAT1, or blocking the glycogen synthase kinase-3β (GSK3β)/β-catenin signaling pathway. Animal experiment was conducted to explore the effect of miR-195-5p on resistance to DDP and angiogenesis.

Result

MiR-195-5p directly targeted PSAT1 and down-regulated its expression. The expression of miR-195-5p was lower while that of PSAT1 was higher in OC tissues than in adjacent normal tissues. When miR-195-5p was over-expressed or PSAT1 was silenced, the expression of HIF-1α, VEGF, PSAT1, β-catenin as well as the extent of GSK3β phosphorylation was reduced, the angiogenesis and resistance to DDP was diminished and apoptosis was promoted both in vitro and in vivo. The inhibition of GSK3β/β-catenin signaling pathway was involved in the regulation process.

Conclusion

Over-expression of miR-195-5p reduced angiogenesis and DDP resistance in OC, which provides a potential therapeutic target for the treatment of OC.

Lysophosphatidic acid induces the migration and invasion of SGC-7901 gastric cancer cells through the LPA2 and Notch signaling pathways

Lysophosphatidic acid (LPA), a simple water‑soluble glycerophospholipid with growth factor‑like activity, regulates certain behaviors of multiple cancer types by binding to its receptor, LPA receptor 2 (LPA2). Notch1 is a key mediator in multiple human cancer cell types. The association between LPA2 and Notch1 in gastric cancer cells is not well known. The present study aimed to investigate the function of LPA2 and Notch1 in controlling the migration and invasion activities of SGC‑7901 gastric cancer cells following stimulation with LPA. It was revealed that LPA may stimulate the expression of Notch1 and Hes family bHLH transcription factor 1, and the phosphorylation of protein kinase B which belongs to the Notch pathway. Furthermore, by performing transwell migration and invasion assays, immunofluorescent staining, analyzing the expression of markers for the epithelial‑mesenchymal transition (EMT) and downregulating LPA2 and Notch1 expression, it was verified that LPA2 and Notch1 mediated the metastasis, invasion, EMT and rebuilding of the cytoskeleton of SGC‑7901 cells upon LPA treatment. An immunoprecipitation assay revealed that LPA2 interacted with Notch1 in SGC‑7901 cells. The present study may provide novel ideas and an experimental basis for identifying the factors that affect the functions of SGC‑7901 cells.

miR-142-5p suppresses proliferation and promotes apoptosis of human osteosarcoma cell line, HOS, by targeting PLA2G16 through the ERK1/2 signaling pathway

Previous studies have revealed that miR-142-5p serves a critical role in human cancer progression. However, the biological function of miR-142-5p in osteosarcoma (OS) development remains unclear. In the present study, the role of miR-142-5p in human OS HOS cells was determined, and the underlying mechanism involved was examined. Compared with the adjacent healthy tissues, the expression level of miR-142-5p was downregulated and the expression level of group XVI phospholipase A2 (PLA2G16) protein was upregulated in human OS tissues. The aforementioned results were also indicated in human OS HOS cells when compared with human fetal osteoblastic hFOB1.19 cells. Additionally, the results demonstrated that PLA2G16 was a direct target of miR-142-5p. miR-142-5p transfection upregulated the expression level of miR-142-5p and suppressed the expression level of PLA2G16 protein in HOS cells. MTT assays indicated a time-dependent decrease by miR-142-5p transfection in the proliferation of HOS cells. 5-bromo-2'-deoxyuridine incorporation assays confirmed that miR-142-5p transfection inhibited DNA synthesis in HOS cells. In addition, miR-142-5p transfection increased the Caspase-3 (CASP3) activity and apoptotic rate. Western blot analysis indicated that miR-142-5p transfection reduced BCL2, apoptosis regulator expression and upregulated the expression of CASP3 and BCL2 associated X, apoptosis regulator in HOS cells. Furthermore, miR-142-5p transfection decreased the expression levels of phosphorylated (p)-proto-oncogene, serine/threonine kinase, p-mitogen-activated protein kinase kinase, and p-extracellular signal-regulated kinase (ERK) 1/2 proteins in HOS cells. PLA2G16 overexpression restored the expression level of p-ERK 1/2 protein, which was reduced by miR-142-5p overexpression. MTT and CASP3 activity assays indicated that restoration of PLA2G16 reversed the tumour-suppressive role of miR-142-5p transfection in HOS cells. In conclusion, the results of the present study indicated that miR-142-5p suppressed proliferation and promoted apoptosis in human OS HOS cells by targeting PLA2G16 through ERK1/2 signaling pathway.

Role of CXCL12-CXCR4 axis in ovarian cancer metastasis and CXCL12-CXCR4 blockade with AMD3100 suppresses tumor cell migration and invasion in vitro

Ovarian cancer (OC) is a lethal gynecologic tumor, which brings its mortality to the head. CXCL12 and its receptor chemokine receptor 4 ( CXCR4) have been found to be highly expressed in OC and contribute to the disease progression by affecting tumor cell proliferation and invasion. Here, in this study, we aim to explore whether the blockade of CXCL12-CXCR4 axis with AMD3100 (a selective CXCR4 antagonist) has effects on the progression of OC. On the basis of the gene expression omnibus database of OC gene expression chips, the OC differentially expressed genes were screened by microarray analysis. OC (nonmetastatic and metastatic) and normal ovarian tissues were collected to determine the expressions of CXCL12 and CXCR4. A series of AMD3100, shRNA against CXCR4, and pCNS-CXCR4 were introduced to treat CAOV3 cells with the highest CXCR4 was assessed. Cell viability, apoptosis, migration, and invasion were all evaluated. The microarray analysis screened out the differential expression of CXCL12-CXCR4 in OC. CXCL12 and CXCR4 expressions were increased in OC tissues, particularly in the metastatic OC tissues. Downregulation of CXCR4 by AMD3100 or shRNA was observed to have a critical role in inhibiting cell proliferation, migration, and invasion of the CAOV3 OC cell line while promoting cell apoptosis. Overexpressed CXCR4 brought significantly promoting effects on the proliferation and invasiveness of OC cells. These results reinforce that the blockade of CXCL12-CXCR4 axis with AMD3100 inhibits the growth of OC cells. The antitumor role of the inhibition of CXCL12-CXCR4 axis offers a preclinical validation of CXCL12-CXCR4 axis as a therapeutic target in OC.

Activity and clinical relevance of autotaxin and lysophosphatidic acid pathways in high-grade serous carcinoma

The aim of this study was to analyze the expression, biological role and clinical relevance of autotaxin (ATX), the enzyme synthetizing lysophosphatidic acid (LPA), and LPA receptors (LPAR) in high-grade serous carcinoma (HGSC). mRNA expression by qRT-PCR of LPAR1-6 was analyzed in 155 HGSC specimens (88 effusions, 67 solid lesions). ATX mRNA expression was analyzed in 97 specimens. ATX, ERK, and AKT protein expression was studied by Western blotting. LPAR2 mRNA was overexpressed in HGSC cells in effusions compared to solid lesions, with opposite findings for LPAR3 and LPAR6 mRNA and ATX protein. Higher LPAR1 levels were significantly related to longer overall survival (OS) in pre-chemotherapy effusions (p = 0.027). Conversely, higher expression of LPAR1, LPAR2, and LPAR5 in post-chemotherapy effusions was significantly associated with shorter OS (p = 0.037, p = 0.025 and p = 0.021, respectively) and progression-free survival (PFS) (p < 0.001, p = 0.007 and p < 0.001, respectively) in univariate survival analysis. LPAR1 mRNA expression was an independent prognosticator of OS in patients with pre-chemotherapy effusions and PFS in patients with post-chemotherapy effusions (p = 0.013 both). In conclusion, LPAR mRNA and ATX protein levels are anatomic site-dependent in HGSC and the former are informative of disease outcome.

Reversal of cisplatin resistance by microRNA-139-5p-independent RNF2 downregulation and MAPK inhibition in ovarian cancer

Some microRNAs (miRs) are dysregulated in cancers, and aberrant miR expression has been reported to correlate with chemoresistance of cancer cells. Therefore, the present study aims at investigating the effects of microRNA-139-5p (miR-139-5p) on cisplatin resistance of ovarian cancer (OC) with involvement of ring finger protein 2 (RNF2) and the mitogen-activated protein kinase (MAPK) signaling pathway. OC tissues were obtained from 66 primary OC patients. The cisplatin-sensitive A2780 and cisplatin-resistant A2780/DDP cell lines were collected for construction of RNF2 silencing and overexpressed plasmids. Cell vitality and apoptosis were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and annexin V-FITC/propidium iodide double-staining, respectively. Next, expression of RNF2, extracellular signal-related kinase, and p38 was determined by quantitative reverse transcription-quantitative polymerase chain reaction and Western blot analysis. Finally, the volume of xenograft tumors in BALB/c nude mice was detected. RNF2 and miR-139-5p were identified to be involved in OC. In addition, MAPK activation and RNF2 were related to cisplatin resistance of OC. miR-139-5p was downregulated in cisplatin-resistant OC tissues, and miR-139-5p overexpression could inhibit cell vitality, reduce cisplatin resistance, and promote apoptosis of OC cells. Furthermore, miR-139-5p combined with MAPK inhibitors more obviously reduced cisplatin resistance of OC. Taken together, this study demonstrated that miR-139-5p overexpression combined with inactivation of the MAPK signaling pathway can reverse the cisplatin resistance of OC by suppressing RNF2. Thus, miR-139-5p overexpression might be a future therapeutic strategy for OC.

PLA2G16 promotes osteosarcoma metastasis and drug resistance via the MAPK pathway

The prognosis of metastatic osteosarcoma is dismal and a better understanding of the mechanisms underlying disease progression is essential to improve treatment options and patient outcomes. We previously demonstrated Pla2g16 overexpression in mouse osteosarcoma contributes to metastasis phenotypes and increased expression of PLA2G16 is associated with metastasis and poor prognosis in human tumors. To further examine the mechanisms through which PLA2G16 contributes to human osteosarcoma metastasis and explore the potential of PLA2G16 as a therapeutic target in osteosarcoma, we generated a panel of human osteosarcoma cell lines expressing different levels of PLA2G16. The functional analyses of these cell lines demonstrated high levels of PLA2G16 expression increased osteosarcoma cell migration, invasion, clonogenic survival, and anchorage-independent colony formation. Importantly, this activity was dependent on the phospholipase activity of PLA2G16. Additionally, PLA2G16 overexpression decreased the sensitivity of cells to a panel of chemotherapeutic agents. Analysis of downstream pathways revealed the pro-metastasis functions of PLA2G16 were mediated through the MAPK pathway, as knockdown of PLA2G16 decreased ERK1/2 phosphorylation and pharmacological inhibition of MEK significantly repressed PLA2G16 mediated cell migration and clonogenic survival. Furthermore, PLA2G16 overexpression promoted xenograft tumor growth in vivo, and these tumors exhibit increased ERK1/2 phosphorylation. Lastly, the expression of PLA2G16 is strongly correlated with the increased ERK1/2 phosphorylation in human osteosarcoma samples, and the combined lesions are associated with reduced overall and metastasis-free survival. Collectively, these results demonstrate increased PLA2G16 expression activates the MAPK pathway to enhance osteosarcoma metastasis and may be a novel therapeutic target for these cancers.

Extracellular HSP70/HSP70-PCs regulate hepatocarcinoma cell migration and invasion via RhoA

The effects of heat shock protein 70 (HSP70)/HSP70-peptide complexes (HSP70-PCs) on the invasion and metastasis ability of hepatocellular carcinoma (HCC) Huh-7 cells were investigated. Wound healing assay revealed that cells treated with HSP70/HSP70-PCs healed faster than negative control cells. HSP70/HSP70-PCs-treated cells also exhibited better migration ability and higher invasion ability than control cells. HSP70/HSP70-PCs treatment did not alter the messenger RNA (mRNA) or protein levels of matrix metalloproteinase-9; the opposite was true for Ras homolog family member A (RhoA) mRNA and protein levels. RNA interference of RhoA attenuated the migration of HSP70/HSP70-PCs-treated cells. The present findings indicate that regulation of HCC cell migration by HSP70/HSP70-PCs occurs via regulation of RhoA expression.

Pharmacological activation of lysophosphatidic acid receptors regulates erythropoiesis

Lysophosphatidic acid (LPA), a growth factor-like phospholipid, regulates numerous physiological functions, including cell proliferation and differentiation. In a previous study, we have demonstrated that LPA activates erythropoiesis by activating the LPA 3 receptor subtype (LPA₃) under erythropoietin (EPO) induction. In the present study, we applied a pharmacological approach to further elucidate the functions of LPA receptors during red blood cell (RBC) differentiation. In K562 human erythroleukemia cells, knockdown of LPA₂ enhanced erythropoiesis, whereas knockdown of LPA₃ inhibited RBC differentiation. In CD34⁺ human hematopoietic stem cells (hHSC) and K526 cells, the LPA₃ agonist 1-oleoyl-2-methyl-sn-glycero-3-phosphothionate (2S-OMPT) promoted erythropoiesis, whereas the LPA₂ agonist dodecyl monophosphate (DMP) and the nonlipid specific agonist GRI977143 (GRI) suppressed this process. In zebrafish embryos, hemoglobin expression was significantly increased by 2S-OMPT treatment but was inhibited by GRI. Furthermore, GRI treatment decreased, whereas 2S-OMPT treatment increased RBC counts and amount of hemoglobin level in adult BALB/c mice. These results indicate that LPA₂ and LPA₃ play opposing roles during RBC differentiation. The pharmacological activation of LPA receptor subtypes represent a novel strategies for augmenting or inhibiting erythropoiesis.

The pathogenic role of angiogenesis in rheumatoid arthritis

Angiogenesis is the formation of new capillaries from pre-existing vasculature, which plays a critical role in the pathogenesis of several inflammatory autoimmune diseases such as rheumatoid arthritis (RA), spondyloarthropathies, psoriasis, systemic lupus erythematosus, systemic sclerosis, and atherosclerosis. In RA, excessive migration of circulating leukocytes into the inflamed joint necessitates formation of new blood vessels to provide nutrients and oxygen to the hypertrophic joint. The dominance of the pro-angiogenic factors over the endogenous angiostatic mediators triggers angiogenesis. In this review article, we highlight the underlying mechanisms by which cells present in the RA synovial tissue are modulated to secrete pro-angiogenic factors. We focus on the significance of pro-angiogenic factors such as growth factors, hypoxia-inducible factors, cytokines, chemokines, matrix metalloproteinases, and adhesion molecules on RA pathogenesis. As pro-angiogenic factors are primarily produced from RA synovial tissue macrophages and fibroblasts, we emphasize the key role of RA synovial tissue lining layer in maintaining synovitis through neovascularization. Lastly, we summarize the specific approaches utilized to target angiogenesis. We conclude that the formation of new blood vessels plays an indispensable role in RA progression. However, since the function of several pro-angiogenic mediators is cross regulated, discovering novel approaches to target multiple cascades or selecting an upstream cascade that impairs the activity of a number of pro-angiogenic factors may provide a promising strategy for RA therapy.

Lysophosphatidic acid signaling in ovarian cancer

Lysophosphatidic acid (LPA) is a bioactive phospholipid that is involved in signal transduction between cells. Plasma and ascites levels of LPA are increased in ovarian cancer patients even in the early stages and thus LPA is considered as a potential diagnostic marker for this disease. This review presents the current knowledge regarding LPA signaling in epithelial ovarian cancer. LPA stimulates proliferation, migration and invasion of ovarian cancer cells through regulation of vascular endothelial growth factor, matrix metalloproteinases, urokinase plasminogen activator, interleukin-6, interleukin-8, CXC motif chemokine ligand 12/CXC receptor 4, COX2, cyclin D1, Hippo-Yap and growth-regulated oncogene α concentrations. In this article, all of these targets and signal pathways involved in LPA influence are described.

[Prognostic values of the clinical, morphological and molecular biological characteristics of colon adenocarcinoma]

OBJECTIVE

to estimate the predictive and prognostic factors using morphological studies in patients with colon cancer to increase survival rates.

SUBJECTS AND METHODS

Immunohistochemical examination was made in 582 patients with colon adenocarcinoma, by determining 11 different indicators relating to the development of the tumor and its treatment.

RESULTS

The simultaneous determination of the chemokine receptor CXCR4 and proliferative activity (Ki-67 expression) can define disease prognosis in view of relapse-survival rates in patients with Stage II colon cancer after radical surgical treatment.

CONCLUSION

Thymidylate synthase and thymidine phosphorylase are of predictive value. The immunohistochemical examination of other markers, such as ALDH1, CCR10, ERCC-1, DYPD, topoisomerase II alpha, and class III beta-tubulin for the choice of treatment policy for patients with colon cancer has indicated that they are of no value.

CXCL12 chemokine expression suppresses human breast cancer growth and metastasis in vitro and in vivo

Chemokine receptors are now known to play an important role in cancer growth and metastasis. However, there is little information regarding chemokine expression in breast cancer. The aim of this study was to evaluate CXCL12 expression in breast cancer and to investigate the question of whether reduced expression of CXCL12 may have any pathological significance in breast cancer development or progression. In this study, we performed western blotting and immunohistochemistry to evaluate the expression of CXCL12 and relevance with clinicopathological factors in the invasive ductal carcinoma. Reduction of CXCL12 was significantly correlated with tumor size, lymph node metastasis, TNM stage and Her-2 expression in breast cancer. Patients with negative CXCL12 expression had significantly lower cumulative postoperative 5 year survival rate than those with positive CXCL12 expression. In addition, we demonstrated that upregulation of CXCL12 expression by infection with an adenovirus containing a CXCL12 vector significantly inhibited cell growth and reduced the migration of breast cancer cells. Furthermore, animal studies revealed that nude mice injected with the Ad-CXCL12 cell lines featured a lighter weight than the control cell lines. These data suggest that CXCL12 plays an important role in cell growth and invasion in human breast cancer and it appears to be a potential prognostic marker for patients with breast cancer.