Predicting chemoresponsiveness in epithelial ovarian cancer patients using circulating small extracellular vesicle-derived plasma gelsolin

BACKGROUND

Resistance to chemotherapy continues to be a challenge when treating epithelial ovarian cancer (EOC), contributing to low patient survival rates. While CA125, the conventional EOC biomarker, has been useful in monitoring patients' response to therapy, there are no biomarkers used to predict treatment response prior to chemotherapy. Previous work in vitro showed that plasma gelsolin (pGSN) is highly expressed in chemoresistant EOC cell lines, where it is secreted in small extracellular vesicles (sEVs). Whether sEVs from tumour cells are secreted into the circulation of EOC patients and could be used to predict patient chemoresponsiveness is yet to be determined. This study aims to identify if sEV-pGSN in the circulation could be a predictive biomarker for chemoresistance in EOC.

METHODS

Sandwich ELISA was used to measure pGSN concentrations from plasma samples of 96 EOC patients (primarily high grade serous EOC). sEVs were isolated using ExoQuick ULTRA and characterized using western blot, nanoparticle tracking analysis, and electron microscopy after which pGSN was measured from the sEVs. Patients were stratified as platinum sensitive or resistant groups based on first progression free interval (PFI) of 6 or 12 months.

RESULTS

Total circulating pGSN was significantly decreased and sEV-pGSN increased in patients with a PFI ≤ 12 months (chemoresistant) compared to those with a PFI > 12 months (chemosensitive). The ratio of total pGSN to sEV-pGSN further differentiated these groups and was a strong predictive marker for chemoresistance (sensitivity: 73.91%, specificity: 72.46%). Predetermined CA125 was not different between chemosensitive and chemoresistant groups and was not predictive of chemoresponsiveness prior to treatment. When CA125 was combined with the ratio of total pGSN/sEV-pGSN, it was a significant predictor of chemoresponsiveness, but the test performance was not as robust as the total pGSN/sEV-pGSN alone.

CONCLUSIONS

Total pGSN/sEV-pGSN was the best predictor of chemoresponsiveness prior to treatment, outperforming the individual biomarkers (CA125, total pGSN, and sEV-pGSN). This multianalyte predictor of chemoresponsiveness could help to inform physicians' treatment and follow up plan at the time of EOC diagnosis, thus improving patients' outcomes.

Plasma gelsolin level predicts acute kidney injury after cardiopulmonary bypass in infants and young children

BACKGROUND

Acute kidney injury (AKI) after cardiopulmonary bypass (CPB) is a common complication especially in pediatric population. Plasma gelsolin (pGSN) is an anti-inflammatory factor through binding with actin and pro-inflammatory cytokines in circulation. Decrease in pGSN has been reported in some pathologic conditions. The purpose of the study was to determine the alterations of pGSN level in infants and young children after CPB and the role of pGSN as a predictor for the morbidity and severity of post-CPB AKI.

METHODS

Sixty-seven infants and young children at age ≤ 3 years old undergoing CPB were prospectively enrolled. PGSN levels were measured during peri-operative period with enzyme-linked immuno-sorbent assay and normalized with plasma total protein concentration. Other clinical characteristics of the patients were also recorded.

RESULTS

In patients developing AKI, the normalized pGSN (pGSN_N) levels significantly decreased at 6 h post-operation and remained low for 24 h post-operation as compared to the patients with non-AKI. PGSN_N at 6 h post-operation combining with CPB time presents an excellent predictive value for AKI.

CONCLUSIONS

Decreased pGSN_N identifies post-CPB AKI in the patients ≤ 3 years old, and is associated with adverse clinical outcomes. The findings suggest that circulating GSN in post-CPB patients may have beneficial effects on diminishing inflammatory responses.

Unexpected profile of sphingolipid contents in blood and bone marrow plasma collected from patients diagnosed with acute myeloid leukemia

Background

Impaired apoptotic pathways in leukemic cells enable them to grow in an uncontrolled way. Moreover, aberrations in the apoptotic pathways are the main factor of leukemic cells drug resistance.

Methods

To assess the presence of potential abnormalities that might promote dysfunction of leukemic cells growth, HPLC system was used to determine sphingosine (SFO), sphinganine (SFA), sphingosine-1-phosphate (S1P) and ceramide (CER) concentration in the blood collected from patients diagnose with acute myeloblastic leukemia (AML; n = 49) and compare to values of control (healthily) group (n = 51). Additionally, in AML group concentration of SFO, SFA, S1P and CER was determined in bone marrow plasma and compared to respective values in blood plasma. The concentration of S1P and CER binding protein – plasma gelsolin (GSN) was also assessed in collected samples using immunoblotting assay.

Results

We observed that in AML patients the average SFO, SFA and CER concentration in blood plasma was significantly higher (p < 0.001) compare to control group, when blood plasma S1P concentration was significantly lower (p < 0.001). At the same time the CER/S1P ratio in AML patient (44.5 ± 19.4) was about 54% higher compare to control group (20.9 ± 13.1). Interestingly the average concentration of S1P in blood plasma (196 ± 13 pmol/ml) was higher compare to its concentration in plasma collected from bone marrow (154 ± 21 pmol/ml).

Conclusions

We hypothesize that changes in profile of sphingolipids concentration and some of their binding protein partners such as GSN in extracellular environment of blood and bone marrow cells in leukemic patients can be targeted to develop new AML treatment method(s).

The role of plasma gelsolin in cardiopulmonary bypass induced acute lung injury in infants and young children: a pilot study

Background

Acute lung injury (ALI) induced by cardiopulmonary bypass (CPB, CPB-ALI) is a common and serious complication after cardiac surgery. And infants and young children are more prone to CPB-ALI. The purpose of this study was to investigate the perioperative changes of plasma gelsolin (pGSN) in patients below 3years of age with cardiac surgeries and CPB, and determine whether pGSN are associated with the occurrence and severity of CPB-ALI.

Methods

Seventy-seven consecutive patients ≤3 years of age with congenital heart diseases (CHD) performed on open heart surgery with CPB were finally enrolled, and assigned to ALI and non-ALI groups according to the American-European Consensus Criteria. Plasma concentrations of gelsolin and total protein were measured at following 8 time points: before CPB (a), after CPB (b), 2 hours after CPB (c), 6 hours after CPB (d), 12 hours after CPB (e), 24 hours after CPB (f), 48 hours after CPB (g) and 72 hours after CPB (h).

Results

Twenty-seven (35.1%) patients developed CPB-ALI in the study, including eleven (14.3%) patients with ARDS. The earliest significant drop of pGSN and normalized pGSN (pGSN_N) of ALI group both occurred at 6 hours after CPB (p = 0.04 and p < 0.01), which was much earlier than those of non-ALI group (48 hours, p = 0.03 and 24 hours, p < 0.01); PGSN of ALI group before CPB and 6 hours after CPB were both significantly lower than those of non-ALI group (p < 0.01); PGSN_N of ALI group before CPB and 6 hours after CPB were both significantly lower than those of non-ALI group (p < 0.01, p = 0.04); PGSN before CPB was the only independent risk factor predicting the occurrence of CPB-ALI (OR, 1.023; 95% CI, 1.007-1.039; p < 0.01) with an AUC of 0.753 (95% CI, 0.626-0.880); The optimal cutoff value of pGSN before CPB was 264.2 mg/L, with a sensitivity of 58.3% and a specificity 94.7%. And lower pGSN before CPB was significantly associated with the severity of CS-AKI (r = −0.45, p < 0.01).

Conclusions

Patients developing CPB-ALI had lower plasma gelsolin reservoir and a much more amount and rapid consumption of plasma gelsolin early after operation. PGSN before CPB was an early and sensitive predictor of CPB-ALI in infants and young children undergoing cardiac surgery, and was negatively correlated with the severity of CPB-ALI.

Plasma gelsolin levels are decreased and correlate with fibrosis in IgA nephropathy

IgA nephropathy (IgAN) is an immune complex glomerulonephritis that is characterized by recurrent hematuria as the main clinical manifestation. In this study, we used the IgAN mouse model which was previously established to investigate the possible mechanism by which IgAN fibrosis correlates with decreased plasma gelsolin (pGSN) levels. We investigated the levels of pGSN, transforming growth factor β1 (TGFβ1), and oxidative stress markers including superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and malondialdehyde (MDA) in the serum and renal tissues of different groups. The between-group differences and correlations in the results for the IgAN group were analyzed with statistical methods. The pathological and urinalysis results obtained from the IgAN mouse model showed that this model conforms to the basic lesion characteristics observed in human IgAN. The serum pGSN levels and SOD, CAT, GSH levels in renal tissues were decreased in the IgAN group (P < 0.01), and pGSN, TGFβ1, MDA levels in renal tissues of the IgAN group were increased which compared with those in the other groups (P < 0.01). The correlation analysis for serum pGSN levels in the IgAN group showed a significant correlation with different test results (P < 0.01). The possible mechanism by which IgAN fibrosis correlates with decreased pGSN levels involves the regulation of TGFβ1 and oxidative stress.

Correlation of plasma gelsolin with chemotherapy efficacy and prognosis in patients with colorectal cancer after radical resection

AIM: To investigate the correlation of plasma gelsolin, a substrate for matrix metalloproteinase, with tumor invasion and metastasis and to explore the possibility of using plasma gelsolin as a putative marker for prediction of chemotherapy efficacy and prognosis in patients with colorectal cancer after radical resection.

METHODS: The clinical data for 40 patients with pathologically confirmed colorectal cancer after surgery were retrospectively analyzed. These patients were divided into two groups according to the progression of the disease, with group A containing patients with stages I and II disease and group B containing those with stage III disease. Patients in group B were further subdivided into group B1 and B2 according to prognosis, with B1 containing patients who underwent postoperative chemotherapy and had metastasis, and B2 containing those who underwent postoperative chemotherapy but had no metastasis. Chemiluminescence immunoassay was used for the monitoring of plasma concentration of gelsolin before and after the first cycle of chemotherapy.

RESULTS: Mean plasma gelsolin before chemotherapy showed no significant differences between groups A and B (76.22 mg/L vs 56.15 mg/L, P > 0.05) and between groups B1 and B2 (62.04 mg/L vs 50.25 mg/L, P > 0.05). After one cycle of chemotherapy, plasma gelsolin was reduced to 54.33 mg/L in group B1, but increased to 84.20 mg/L in group B2 (t =- 2.540, P = 0.032). Mean plasma gelsolin decreased by 10.56% in group B1 but increased by 47.36% in group B2, showing a significant difference between the two groups (t =- 4.430, P = 0.002).

CONCLUSION: Monitoring of plasma gelsolin in patients with colorectal cancer after radical resection during early chemotherapy can help predict long-term efficacy of chemotherapy and prognosis.