Low caveolin-1 levels and symptomatic intracranial haemorrhage risk in large-vessel occlusive stroke patients after endovascular thrombectomy.

BACKGROUND AND PURPOSE: Caveolin-1 (Cav-1) is reported to mediate blood-brain barrier integrity after ischaemic stroke. Our purpose was to assess the role of circulating Cav-1 levels in predicting symptomatic intracranial haemorrhage (sICH) amongst ischaemic stroke patients after endovascular thrombectomy (EVT). METHODS: Patients with large-vessel occlusive stroke after EVT from two stroke centres were prospectively included. Serum Cav-1 level was tested after admission. sICH was diagnosed according to the Heidelberg Bleeding Classification. RESULTS: Of 325 patients (mean age 68.6 years; 207 men) included, 47 (14.5%) were diagnosed with sICH. Compared with patients without sICH, those with sICH had a lower concentration of Cav-1. After adjusting for potential confounders, multivariate regression analysis demonstrated that the increased Cav-1 level was associated with a lower sICH risk (odds ratio 0.055; 95% confidence interval 0.005-0.669; p = 0.038). Similar results were obtained when Cav-1 levels were analysed as a categorical variable. Using a logistic regression model with restricted cubic splines, a linear and negative association of Cav-1 concentration was found with sICH risk (p = 0.001 for linearity). Furthermore, the performance of the conventional risk factors model in predicting sICH was substantially improved after addition of the Cav-1 levels (integrated discrimination index 2.7%, p = 0.002; net reclassification improvement 39.7%, p = 0.007). CONCLUSIONS: Our data demonstrate that decreased Cav-1 levels are related to sICH after EVT. Incorporation of Cav-1 into clinical decision-making may help to identify patients at a high risk of sICH and warrants further consideration.

Clinical evidence for elevated levels of caveolin-1 in circulation of patients with diabetic foot ulcers.

Caveolin-1 directly interacts vascular endothelial growth factor receptor-2 (VEGFR2) and therefore prevents VEGF-induced angiogenesis. In addition, the production of nitric oxide (NO), which is effective in reducing ischemia in diabetic foot ulcers (DFU), is suppressed by caveolin-1 in endothelial cells. The present study was designed to investigate the change of caveolin-1 concentrations in DFU patients. A total of 150 participants were consecutively enrolled, including 40 DFU patients (DFU group), 40 diabetes patients without DFU (type 2 diabetes mellitus [T2DM] group), and 70 participants without diabetes (control group). Significant increased levels of plasma caveolin-1, accompanied with decreased concentration of plasma VEGF-A (vascular endothelial growth factor-A) and NO, were detected in DFU patients. Moreover, Pearson's correlation analysis revealed a negative correlation between plasma caveolin-1 and VEGF-A as well as NO levels in DFU patients. Furthermore, DFU patients had higher expression of caveolin-1 in the popliteal artery, compared to those in control and T2DM groups. Simultaneously, the amounts of eNOS (an enzyme responsible for the production of NO) and VEGFR2 were attenuated in the popliteal artery of DFU patients. Taken together, our study provided clinical evidence for the possible association of elevated caveolin-1 levels and the development of DFU. This may be induced by the suppressed VEGF-A/VEGFR2 and eNOS/NO signalling axis.

Expression of caveolin family proteins in serum of patients with systemic lupus erythematosus.

OBJECTIVES: Caveolin family proteins, including caveolin-1 (Cav-1), caveolin-2 (Cav-2), and caveolin-3 (Cav-3), are identified as the principal protein components of caveolae in mammalian cells. Circulating form of caveolin family proteins can be used as a good potential biomarker for predicting disease. METHODS: To investigate the clinical significance of the serological levels of caveolin family proteins in patients with systemic lupus erythematosus (SLE), we evaluated the soluble serum levels of caveolin family proteins in patients with SLE by enzyme-linked immunosorbent assay (ELISA) and assessed their associations with various known clinical variables. RESULTS: The major findings of our study are as follows: Cav-2 was not detected in serum of SLE patients and normal controls (NCs). Serum Cav-1 and Cav-3 levels were higher in SLE patients compared with NCs. There were no significant correlations between serum Cav-1 and Cav-3 levels and SLE disease activity. Further analysis showed that serum Cav-3 may be more valuable as a marker than serum Cav-1 in SLE patients. CONCLUSION: Serum levels of Cav-1 and Cav-3 might have a diagnostic role in patients with SLE. However, their predictive and prognostic value was not determined. Further studies are necessary to determine the potential clinical significance of these assays in SLE.

Low Pre-Transplant Caveolin-1 Serum Concentrations Are Associated with Acute Cellular Tubulointerstitial Rejection in Kidney Transplantation.

Acute and chronic transplant rejections due to alloreactivity are essential contributors to graft loss. However, the strength of alloreactivity is biased by non-immunological factors such as ischemia reperfusion injury (IRI). Accordingly, protection from IRI could be favorable in terms of limiting graft rejection. Caveolin-1 (Cav-1) is part of the cell membrane and an important regulator of intracellular signaling. Cav-1 has been demonstrated to limit IRI and to promote the survival of a variety of cell types including renal cells under stress conditions. Accordingly, Cav-1 could also play a role in limiting anti-graft immune responses. Here, we evaluated a possible association between pre-transplant serum concentrations of Cav-1 and the occurrence of rejection during follow-up in a pilot study. Therefore, Cav-1-serum concentrations were analyzed in 91 patients at the time of kidney transplantation and compared to the incidence of acute and chronic rejection. Higher Cav-1 levels were associated with lower occurrence of acute cellular tubulointerstitial rejection episodes.

Association between caveolin-1 and stroke: a systematic review and meta-analysis.

OBJECTIVE: Caveolin-1 plays critical roles in regulating signal transduction and cholesterol trafficking in cells. However, the relationship between caveolin-1 and stroke remains less reported. MATERIALS AND METHODS: In this study, we reviewed information from seventeen studies to get the qualitative evidence of the influence of the caveolin-1 on stroke and collected data from three of the seventeen studies to conduct meta-analysis. The original studies classified participants into two groups with stroke group and control group, respectively. The random-effect model was used in the meta-analysis with the standardized mean difference (SMD) as the measure indicator. RESULTS: Our data showed that the SMD (95% confidence intervals, CIs) between the control group and the stroke group was -0.5449 [-2.3344, 1.0000]. For the subgroup analysis, The SMD (95% confidence intervals, CIs) between the control group and the ischemic stroke group was -1.4589 [-5.0129, 2.0951], and between the control group and the hemorrhagic stroke group was 0.3438 [-0.4140, 1.1017]. CONCLUSIONS: Although the differences are not statistically significant between the two groups, the high level of caveolin-1 are associated with the stroke, which may remedy the stroke. Besides, an opposite result was observed for the association of the caveolin-1 on the ischemic stroke and hemorrhagic stroke. To confirm this association, further studies are necessary.

Caveolin-1-mediated sphingolipid oncometabolism underlies a metabolic vulnerability of prostate cancer.

Plasma and tumor caveolin-1 (Cav-1) are linked with disease progression in prostate cancer. Here we report that metabolomic profiling of longitudinal plasmas from a prospective cohort of 491 active surveillance (AS) participants indicates prominent elevations in plasma sphingolipids in AS progressors that, together with plasma Cav-1, yield a prognostic signature for disease progression. Mechanistic studies of the underlying tumor supportive onco-metabolism reveal coordinated activities through which Cav-1 enables rewiring of cancer cell lipid metabolism towards a program of 1) exogenous sphingolipid scavenging independent of cholesterol, 2) increased cancer cell catabolism of sphingomyelins to ceramide derivatives and 3) altered ceramide metabolism that results in increased glycosphingolipid synthesis and efflux of Cav-1-sphingolipid particles containing mitochondrial proteins and lipids. We also demonstrate, using a prostate cancer syngeneic RM-9 mouse model and established cell lines, that this Cav-1-sphingolipid program evidences a metabolic vulnerability that is targetable to induce lethal mitophagy as an anti-tumor therapy.

Subanesthetic Dose of Ketamine Improved CFA-induced Inflammatory Pain and Depression-like Behaviors Via Caveolin-1 in Mice.

BACKGROUND: Ketamine, a commonly used nonbarbiturate anesthetic drug, possesses antidepressant properties at subanesthetic doses; however, the underlying mechanisms remain unclear. MATERIALS AND METHODS: The analgesic and antidepressant effects of ketamine were explored using a complete Freund adjuvant (CFA)-induced peripheral inflammatory pain model in vivo. Mice were first divided into sham or CFA injection group randomly, and were observed for mechanical hyperalgesia, depression-like behavior, and mRNA expression of caveolin-1. Then ketamine was administered in CFA-treated mice at day 7. RESULTS: The behavioral testing results revealed mechanical hyperalgesia and depression in mice from days 7 to 21 after CFA injection. Ketamine reversed depression-like behaviors induced by CFA injection. It also restored the brain-regional expression levels of caveolin-1 in CFA-treated mice. In addition, caveolin-1 mRNA and protein expression were increased in the prefrontal cortex and nucleus accumbens of CFA-treated mice. However, ketamine reversed the increase in caveolin-1 expression in the ipsilateral and contralateral prefrontal cortex and nucleus accumbens, supporting the distinct roles of specific brain regions in the regulation of pain and depression-like behaviors. CONCLUSIONS: In CFA-treated mice that exhibited pain behavior and depression-like behavior, ketamine reversed depression-like behavior. The prefrontal cortex and nucleus accumbens are the important brain regions in this regulation network. Despite these findings, other molecules and their mechanisms in the signal pathway, as well as other regions of the brain in the pain matrix, require further exploration.

Serum caveolin-1 levels in patients with preeclampsia.

Aim: The expressions of caveolin-1 have only been examined in the placental tissue of patients with preeclampsia and were reported to be low. Therefore, we decided to investigate the maternal serum levels of caveolin-1 in patients with preeclampsia.Material and methods: This cross-sectional study was conducted including 87 pregnant women; 32 with normal pregnancy and 55 with preeclampsia. Maternal serum levels of caveolin-1 were measured by using enzyme-linked immunosorbent assay kit (ELISA).Results: The mean serum caveolin-1 level was significantly lower in women with preeclampsia (PE) compared with the control group (11.48 ± 0.92 versus 12.94 ± 1.36 ng/ml) and being lowest in the early onset PE group (11.24 ± 0.74 ng/ml). Serum caveolin-1 concentrations did not correlate with maternal age and BMI. However, caveolin-1 concentrations were negatively correlated with systolic blood pressure (r = -0.467, p = .001) and diastolic blood pressure (r = -0.441, p = .001) as well as with umbilical artery resistance index (r = -0.275, p = .01).Conclusion: Maternal serum caveolin-1 levels are significantly lower in patients with PE than controls. The serum caveolin-1 levels inversely correlate with blood pressure and umbilical artery Doppler parameters.

The CAV1 Gene 3' Untranslated Region Single Nucleotide Polymorphisms Are Associated with the Risk of Pulmonary Hypertension in Chinese Han Chronic Obstructive Pulmonary Patients.

Aims: Caveolin-1, which is encoded by the caveolin-1 (CAV1) gene, plays an important role in the development of pulmonary hypertension (PH). The purpose of this study was to determine the relationship between 3' untranslated region (UTR) single nucleotide polymorphisms (SNPs) of the CAV1 gene and the risk of PH in Chinese Han patients with chronic obstructive pulmonary disease (COPD). Methods: From March 2016 to October 2018, 235 patients with COPD combined with PH (COPD/PH+) and 240 patients with COPD and without PH (COPD/PH-) were recruited to the study. The CAV1 gene rs1049314, rs8713, rs1049334, rs6867, and rs1049337 loci were genotyped and the plasma hsa-miR-451 and caveolin-1 levels were measured in all subjects. Results: The risk of PH in patients with COPD carrying the C allele of the rs8713 locus was 2.82 times higher than that in A allele carriers (95% confidence interval [CI], 1.94-4.08; p < 0.001). The risk of PH in patients with COPD carrying the T allele of the rs1049337 locus was significantly lower than that in C allele carriers (odds ratio [OR], 0.48; 95% CI, 0.37-0.63; p < 0.001). The ACGAC haplotype was found to be a highly-significant risk factor for COPD combined with PH (OR, 2.24; 95% CI, 1.20-4.17; p = 0.01). Plasma levels of hsa-miR-451 and the caveolin1 protein in patients with the rs8713 C allele were significantly lower than in those with the wild type (WT) allele regardless of PH status. Conversely, the hsa-miRN-451 and caveolin-1 levels in patients with the rs1049337 mutant C allele were significantly higher than those in the WT T allele (p < 0.05). There was a positive correlation between plasma hsa-miR-451 and caveolin-1 levels in patients with COPD/PH+ and COPD/PH- (r = 0.72 and 0.63, respectively). Conclusion: SNPs of the CAV1 gene loci rs8713 and rs1049337 are associated with a risk of PH in COPD patients. The underlying mechanism is likely to be related to the effect of the SNPs on the regulation of caveolin-1 by hsa-miR-451.

Simvastatin delays castration­resistant prostate cancer metastasis and androgen receptor antagonist resistance by regulating the expression of caveolin­1.

The failure of androgen deprivation therapy in prostate cancer treatment mainly results from drug resistance to androgen receptor antagonists. Although an aberrant caveolin­1 (Cav­1) expression has been reported in multiple tumor cell lines, it is unknown whether it is responsible for the progression of castration­resistant prostate cancer (CRPC). Thus, the aim of the present study was to determine whether Cav­1 can be used as a key molecule for the prevention and treatment of CRPC, and to explore its mechanism of action in CRPC. For this purpose, tissue and serum samples from patients with primary prostate cancer and CRPC were analyzed using immunohistochemistry and enzyme­linked immunosorbent assay, which revealed that Cav­1 was overexpressed in CRPC. Furthermore, Kaplan­Meier survival analysis and univariate Cox proportional hazards regression analysis demonstrated that Cav­1 expression in tumors was an independent risk factor for the occurrence of CRPC and was associated with a shorter recurrence­free survival time in patients with CRPC. Receiver operating characteristic curves suggested that serum Cav­1 could be used as a diagnostic biomarker for CRPC (area under the curve, 0.876) using a cut­off value of 0.68 ng/ml (with a sensitivity of 82.1% and specificity of 80%). In addition, it was determined that Cav­1 induced the invasion and migration of CRPC cells by the activation of the H­Ras/phosphoinositide­specific phospholipase Cε signaling cascade in the cell membrane caveolae. Importantly, simvastatin was able to augment the anticancer effects of androgen receptor antagonists by downregulating the expression of Cav­1. Collectively, the findings of this study provide evidence that Cav­1 is a promising predictive biomarker for CRPC and that lowering cholesterol levels with simvastatin or interfering with the expression of Cav­1 may prove to be a useful strategy with which to prevent and/or treat CRPC.

Maternal chronic intermittent hypoxia in rats causes early atherosclerosis with increased expression of Caveolin-1 in offspring.

OBJECTIVE: The objective of our research was to explore the effects of maternal and postpartum chronic intermittent hypoxia (CIH) exposure on atherosclerosis in adulthood offspring of rats, and the role of Caveolin-1 in the course. METHODS: Sixteen rats were assigned to two groups (n = 8), maternal normoxia and CIH group. After delivery, two male pups per litter were selected and breastfed for 1 month, which then randomly received postpartum normoxia or CIH. Thus, 4 groups were created as follows (n = 8): (1) maternal normoxia and postpartum normoxia group, (2) maternal CIH and postpartum normoxia group, (3) maternal CIH and postpartum CIH group, and (4) maternal normoxia and postpartum CIH group. The offspring were weighed at birth and weaning. After the duration of 12-week experiment, morphological changes, the expression of Caveolin-1 and NF-κB p65 in the aorta were detected. RESULTS: Maternal CIH resulted in significantly lower body weight and thicker intima (P < 0.001). CIH upregulated the expression of Caveolin-1 and NF-κB p65 significantly (P < 0.01). There was a synergistic effect of maternal and postpartum CIH on the thickening of intima (P < 0.05), also on the expression of Caveolin-1 and NF-κB p65 (P < 0.01). CONCLUSIONS: The results demonstrate that maternal CIH exposure causes a postpartum catch-up growth and early atherosclerotic changes followed by upregulating Caveolin-1 expression. Besides, maternal CIH enhances the atherosclerotic changes caused by postpartum CIH. Oxidative stress probably implicates in above effects.

Downregulated Caveolin-1 expression in circulating monocytes may contribute to the pathogenesis of psoriasis.

Caveolin-1 (CAV-1) is the principal component of caveolae that regulates a variety of signaling molecules and receptors. Our previous study revealed CAV-1 reduction in the epidermis of patients with psoriasis, which leads to enhanced Janus kinase/signal transducer and activator of transcription activation and cytokine production, suggesting that aberrant CAV-1 expression may contribute to psoriatic inflammation. This study aimed to investigate whether abnormal modulation of CAV-1 on immune cells is involved in the pathogenesis of psoriasis. We observed that CAV-1 level in psoriasis patients was apparently reduced in peripheral blood mononuclear cells (PBMCs) and it was prominent in CD14+ monocytes. CAV-1 silencing in monocytes represented elevated levels of interleukin (IL)-1ß and IL-6, and those had enhanced chemotaxis activity. In a murine model of psoriasis-like inflammation induced by imiquimod, we observed a significant CAV-1 reduction in PBMCs. Systemic administration of CAV-1 scaffolding domain peptide significantly improved the skin phenotype with less macrophage infiltration. Taken together, aberrant CAV-1 expression in monocytes may be involved in the pathogenesis of psoriasis.

Clinical significance of serum caveolin-1 levels in gastric cancer patients.

Caveolin-1 plays a significant role in the pathogenesis of various carcinomas and its expression affects the survival of cancer patients. However, the molecular function of caveolin-1 and its possible clinical importance has remained uncertain in gastric cancer. No clinical trial has examined serum caveolin-1 levels in gastric cancer patients so far, instead all available results were provided from studies conducted on tissue samples. In the current study, we analyzed the soluble serum caveolin-1 levels in gastric cancer patients, and specified its associations with the clinical factors and prognosis. MATERIAL AND METHODS: Sixty-three patients with pathologically confirmed gastric cancer were enrolled into the trial. Serum caveolin-1 concentrations were detected by ELISA method. Thirty healthy subjects were also included in the study. RESULTS: The median age of patients was 62 years, ranging from 28 to 82 years. The serum caveolin-1 levels in gastric cancer patients were significantly higher than those in control group (p < 0.001). The common clinical parameters including patient age, sex, lesion localization, histopathology, histological grade, disease stage, and various serum tumor markers (e.g. LDH, CEA, and CA 19.9) were not found to be associated with serum caveolin-1 levels (p > 0.05). Similarly, no correlation existed between serum caveolin-1 concentration and chemotherapy responsiveness (p = 0.93). Furthermore, serum caveolin-1 level was not found to have a prognostic role (p = 0.16). CONCLUSION: Even though it is neither predictive nor prognostic, serum caveolin-1 level may be a valuable diagnostic indicator in patients with gastric cancer.

Low Levels of Caveolin-1 Predict Symptomatic Bleeding After Thrombolytic Therapy in Patients With Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Experimental models of cerebral ischemia demonstrate that the decrease in the caveolin-1 membrane protein results in an increase in endothelial permeability. Because this phenomenon is responsible for hemorrhagic transformation (HT) after cerebral ischemia, we aimed to determine whether caveolin-1 levels may predict bleeding after recombinant tissue-type plasminogen activator (r-tPA) administration in patients with acute stroke. METHODS: We studied 133 patients with a first hemispheric stroke treated with r-tPA within 4.5 hours of symptom onset. HT was evaluated and classified on cranial computed tomography at 24 hours and was considered as symptomatic HT (sHT) if associated with neurological deterioration. Serum caveolin-1 levels were analyzed before and at 2, 24, and 72 hours post-r-tPA administration in patients and in 40 healthy controls. RESULTS: Baseline caveolin-1 levels were higher in patients than controls (0.24 [0.17-0.40] versus 0.07 [0.0-0.20] ng/mL; P<0.000). Twenty six (19.5%) patients had HT, which was symptomatic in 7 (5.3%). Patients with parenchymal hemorrhage-2 and sHT had lower baseline caveolin-1 levels than the rest of patients (0.08 [0.04-0.19] versus 0.26 [0.14-0.40]; P=0.019 and 0.08 [0.02-0.17] versus 0.26 [0.13-0.41]; P=0.019, respectively). The levels remained stable in the first 72 hours in patients with parenchymal hemorrhage-2 and sHT, whereas in the rest of patients levels decreased in this time. Caveolin-1 levels ≤0.17 ng/mL had the highest predictive capacity of sHT (86% sensitivity, 65% specificity, 99% negative predictive value, 12% positive predictive value). After adjustment for confounders, caveolin-1 levels ≤0.17 ng/mL independently predicted sHT (odds ratio, 11.6; 95% confidence interval, 11.3-102.8; P=0.027). CONCLUSIONS: Low serum levels of caveolin-1 are an independent predictor of sHT after r-tPA administration. Because of the small sample size, further research is needed to validate these data.

Baseline and longitudinal plasma caveolin-1 level as a biomarker in active surveillance for early-stage prostate cancer.

OBJECTIVES: To evaluate the role of caveolin-1 (Cav-1) as a predictor of disease reclassification (DR) in men with early prostate cancer undergoing active surveillance (AS). PATIENTS AND METHODS: We analysed archived plasma samples prospectively collected from patients with early prostate cancer in a single-institution AS study. Of 825 patients enrolled, 542 had ≥1 year of follow-up. Baseline and longitudinal plasma Cav-1 levels were measured using an enzyme-linked immunosorbent assay. Tumour volume or Gleason grade increases were criteria for DR. Logistic regression analyses were used to assess associations between clinicopathological characteristics and reclassification risk. RESULTS: In 542 patients, 480 (88.6%) had stage cT1c disease, 542 (100.0%) had a median prostate-specific antigen level of 4.1 ng/mL, and 531 (98.0%) had a median Cancer of the Prostate Risk Assessment score of 1. In all, 473 (87.3%) had a Gleason score of 3+3. After a median of 3.1 years of follow-up, disease was reclassified in 163 patients (30.1%). The mean baseline Cav-1 level was 2.2 ± 8.5 ng/mL and the median 0.2 ng/mL (range, 0-85.5 ng/mL). In univariate analysis, baseline Cav-1 was a significant predictor for risk of DR (odds ratio [OR] 1.82, 95% confidence interval [CI] 1.24-2.65; P = 0.002). In multivariate analysis, with adjustments for age, tumour length, group risk stratification and number of positive cores, reclassification risk associated with Cav-1 remained significant (OR 1.91, 95% CI 1.28-2.84; P = 0.001). CONCLUSION: Baseline plasma Cav-1 level was an independent predictor of disease classification. New methods for refining AS and intervention may result.

The influence of caveolin-1 gene polymorphisms on hepatitis B virus-related hepatocellular carcinoma susceptibility in Chinese Han population: A case-control study.

This study aimed to explore the genetic association of polymorphisms in caveolin-1 gene (CAV1) with hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC) susceptibility in a Chinese Han population.The genotyping of polymorphism was conducted using polymerase chain reaction-restriction fragment length polymorphism method. Whether the genotype distribution of polymorphisms in the healthy controls was consistent with Hardy-Weinberg equilibrium (HWE) was detected. The genotype and allele frequency difference between the 2 groups was compared by chi-square test. Odds ratio (OR) and 95% confidence interval (95% CI) were calculated to show the relative risk of HCC which resulted from genetic variants in CAV1. Moreover, the linkage disequilibrium of CAV1 polymorphisms was analyzed by Haploview.The AG genotype and A allele of rs1049334 showed significantly higher frequency in HCC patients than that of chronic HBV patients and the healthy controls (P < .05); so their carriage obviously increased the susceptibility to HBV-related HCC, irrespective of the fact whether individuals were infected with hepatitis B virus or not (AG vs GG: OR 1.958, 95% CI 1.050-3.650, OR 1.899, 95% CI 1.034-3.487; A vs G: OR 1.667, 95% CI 1.033-2.689, OR 1.777, 95% CI 1.103-2.863). Additionally, A-G haplotype of rs3807989-rs1049334 showed the protective role for HBV-related HCC (OR 0.102, 95% CI 0.035-0.293; OR 0.135, 95% CI 0.046-0.395).CAV1 rs1049334 polymorphism is significantly associated with the occurrence risk of HBV-related HCC, and the interaction of polymorphisms should not be neglected.

Is plasma caveolin-1 level a prognostic biomarker in metastatic pancreatic cancer?

BACKGROUND/AIMS: To evaluate the prognostic significance of plasma caveolin (CAV)-1 and its association with survival and treatment response rates in metastatic pancreatic cancer (MPC). PATIENTS AND METHODS: Plasma samples were prospectively collected from 41 patients with newly diagnosed MPC. Moreover, plasma samples were collected from 48 patients with chronic pancreatitis and 41 healthy individuals (control groups) for assessing Cav-1 levels. Plasma Cav-1 levels were evaluated at baseline and after three cycles of chemotherapy in the patients with MPC. RESULTS: The median Cav-1 level was 13.8 ng/mL for the patients with MPC and 12.2 ng/mL for healthy individuals (P = 0.009). The Cav-1 cut-off level was calculated as 11.6 ng/mL by using the receiver operating characteristic curve. The median overall survival and progression-free survival rates were 5 and 2.4 months, respectively, for participants with a high basal plasma Cav-1 level; the corresponding values were 10.5 and 9.4 months for participants with a low plasma Cav-1 level (P = 0.011 and P= 0.003, respectively). Of the 41 patients with MPC, 23 completed at least three cycles of chemotherapy. The median Cav-1 level was 13 ng/mL for post-treatment MPC (r2: 0.917; P= 0.001). High basal plasma caveolin-1 level have continued to remain at high levels even after chemotherapy, showing a trend toward worse response rates (P = 0.086). CONCLUSION: High basal plasma Cav-1 levels seem to be associated with poor survival and tend to yield worse therapeutic outcomes in patients with MPC. This study is the first to evaluate the prognostic significance of plasma Cav-1 levels as a prognostic factor in patients with MPC. However, larger prospective clinical trials are warranted.

TLR4 and Caveolin-1 in Monocytes Are Associated With Inflammatory Conditions in Diabetic Neuropathy.

The purpose of this study was to investigate the expression of TLR4 and caveolin-1 in monocytes among healthy volunteers as well as those with type-2 diabetes mellitus (T2DM) and diabetic peripheral neuropathy (DPN). Nineteen healthy control subjects, 18 patients with T2DM, and 20 patients with DPN were enrolled. Toll-like receptor (TLR)4, caveolin-1, MyD88, phosphorylated IκB, and plasma TNF-α and interleukin (IL)-6 were measured using real-time polymerase chain reaction, Western blotting, and enzyme-linked immunosorbent assay. Compared with the other two groups, the DPN group had higher expression of TLR4, MyD88, phosphorylated IκB, TNF-α, and IL-6, but significantly lower levels of caveolin-1 and total IκB in monocytes. Plasma concentrations of TNF-α and IL-6 were positively correlated with TLR4 and negatively correlated with caveolin-1 in patients with DPN. Plasma concentration of TLR4 was negatively correlated with caveolin-1 in patients with DPN. Reduced expression of caveolin-1 in monocytes could aggravate the TLR4-mediated inflammatory cascade.

Caveolin-1 Promotes the Imbalance of Th17/Treg in Patients with Chronic Obstructive Pulmonary Disease.

The imbalance of Th17/Treg cells plays an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Caveolin-1 (Cav-1) has been regarded as a potential critical regulatory protein in pathological mechanisms of chronic inflammatory respiratory diseases. Therefore, we investigated whether the loss of Cav-1 is involved in the homeostasis of Th17/Treg cells in COPD. We examined the expressions of plasma Cav-1 and circulating Th17, Treg cells, and the related cytokines in patients with COPD. Enzyme-linked immunosorbent assay (ELISA) analyses showed a significant reduction of plasma Cav-1 levels in patients with stable COPD (SCOPD) and acutely exacerbated COPD (AECOPD) compared to smokers without COPD. This loss was associated with an increase in frequency of Treg and decreased in frequency of Th17 cells. To further identify the role of Cav-1, we studied the effects of Cav-1 overexpression or downregulation on frequencies of Treg and Th17 cells in peripheral blood mononuclear cells (PBMCs) from subjects. Interestingly, small interfering RNA (siRNA) downregulation of Cav-1 was accompanied by an augmentation of Treg and reduction of Th17 expression. Together, our study demonstrated that the loss of Cav-1 contributed to the imbalance of Th17/Treg cells in patients with COPD.

Is Serum Caveolin-1 a Useful Biomarker for Progression in Patients with Colorectal Cancer?.

BACKGROUND: Colorectal cancer (CRC) is the third most common cause of cancer diagnosed in males and the second in females. Survival is strongly related to stage at diagnosis. There is an urgent need to find a noninvasive biomarker that can be commonly applied for screening diagnosis, early detection of recurrence, and monitoring of metastatic CRC. Protein caveolin-1 (CAV-1) has been known to be expressed abnormally in colon cancer and appears to contribute to aberrant signaling and protein trafficking. There are controversial results regarding the role of CAV-1 in cancer. We hypothesized that levels of CAV-1 in serum of patients with CRC might be important to estimate the progression of the disease. Therefore, the purpose of this study is to investigate whether serum CAV-1 might be used as a factor determining progression of CRC. METHODS: A total of 61 patients with CRC (26 male, 35 female) and 46 controls (38 male, 8 female) were enrolled. Serum CAV-1 levels were measured by ELISA. The relationship between CAV-1 and progression-free survival (PFS) was analyzed with use of receiver operating characteristic (ROC) and Kaplan-Meier analysis. Results were given as median (95% CI). Mann-Whitney test was used for the comparison of groups. RESULTS: CAV-1 levels were found to be 11.5 ng/mL (10.4-12.9) in CRC and 11.9 ng/mL (10.7-14.4) in controls (p = 0.465). The serum CAV-1 levels in CRC patients with disease progression and without progression were respectively 10.0 ng/mL (8.5-11.3) and 12.2 ng/mL (11.1-14.8) (p = 0.023). In ROC analysis, if CAV-1 levels are equal or lesser than 10.73 ng/mL, it might show presence of progression with a sensitivity 73.3% and specificity 66.7% in patients with CRC (area under the ROC curve (AUC) = 0.697, p = 0.005). The mean PFS time was found to be 29.7 months (19.8-39.7, 95% CI for the mean) in patients who have CAV-1 level ≤ 10.73 ng/mL and 61.9 months (44.2-79.6) in patients who have CAV-1 level > 10.73 ng/mL [hazard ratios (HR) with 95% CI = 3.49 (1.26 - 9.68) (p = 0.017)]. CONCLUSIONS: Our results strongly suggest that CAV-1 levels might be used as a marker to determine progression of CRC. When considered in combination with other biomarkers of CRC, CAV-1 is clinically informative and instructive.