Transient elevation of serum cystatin C concentrations during perioperative cisplatin-based chemotherapy in esophageal cancer patients

CamGFR v2: A New Model for Estimating the Glomerular Filtration Rate from Standardized or Non-standardized Creatinine in Patients with Cancer

PURPOSE

Management of patients with cancer, specifically carboplatin dosing, requires accurate knowledge of glomerular filtration rate (GFR). Direct measurement of GFR is resource limited. Available models for estimated GFR (eGFR) are optimized for patients without cancer and either isotope dilution mass spectrometry (IDMS)- or non-IDMS-standardized creatinine measurements. We present an eGFR model for patients with cancer compatible with both creatinine measurement methods.

EXPERIMENTAL DESIGN

GFR measurements, biometrics, and IDMS- or non-IDMS-standardized creatinine values were collected for adult patients from three cancer centers. Using statistical modeling, an IDMS and non-IDMS creatinine-compatible eGFR model (CamGFR v2) was developed. Its performance was compared with that of the existing models Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Modification of Diet in Renal Disease (MDRD), Full Age Spectrum (FAS), Lund-Malmö revised, and CamGFR v1, using statistics for bias, precision, accuracy, and clinical robustness.

RESULTS

A total of 3,083 IDMS- and 4,612 non-IDMS-standardized creatinine measurements were obtained from 7,240 patients. IDMS-standardized creatinine values were lower than non-IDMS-standardized values in within-center comparisons (13.8% lower in Cambridge; P < 0.0001 and 19.3% lower in Manchester; P < 0.0001), and more consistent between centers. CamGFR v2 was the most accurate [root-mean-squared error for IDMS, 14.97 mL/minute (95% confidence interval, 13.84-16.13) and non-IDMS, 15.74 mL/minute (14.86-16.63)], most clinically robust [proportion with >20% error of calculated carboplatin dose for IDMS, 0.12 (0.09-0.14) and non-IDMS, 0.17 (0.15-0.2)], and least biased [median residual for IDMS, 0.73 mL/minute (-0.68 to 2.2) and non-IDMS, -0.43 mL/minute (-1.48 to 0.91)] eGFR model, particularly when eGFR was larger than 60 ml/minute.

CONCLUSIONS

CamGFR v2 can utilize IDMS- and non-IDMS-standardized creatinine measurements and outperforms previous models. CamGFR v2 should be examined prospectively as a practice-changing standard of care for eGFR-based carboplatin dosing.

Serum proteomics analysis of candidate predictive biomarker panel for the diagnosis of trastuzumab-based therapy resistant breast cancer

Human epidermal growth factor receptor 2 (HER2)-positive is a particularly aggressive type of the breast cancer. Trastuzumab-based therapy is a standard treatment for HER2-positive breast cancer, but some patients are resistant to the therapy. Serum proteins have been used to predict therapeutic benefit for various cancers, but whether serum proteins can serve as biomarkers for HER2-positive breast cancer remains unclear. Using an isobaric Tandem Mass Tag (TMT) label-based quantitative proteomic, we discovered 18 differentially expressed proteins in the serum of trastuzumab-based therapy resistant patients before therapy. Then, four proteins were selected and validated using an LC-MS/MS-based multiple reaction monitoring quantification method, and it was confirmed that three proteins (SRGN, LDHA and CST3) were correlated with trastuzumab-based therapy resistance. Finally, the trastuzumab-based therapy resistance diagnostic score was calculated and acquired by means of a logistic regression pattern based on the level of these three proteins. In summary, we develop a serum-based protein signature that potentially predicts the therapeutic effects of trastuzumab-based therapy for HER2-positive breast cancer patients.

Serum Cystatin C as a Potential Marker for Glomerular Filtration Rate in Patients with Cholangiocarcinoma

Background: Cholangiocarcinoma (CCA) is the second most common primary hepatobiliary cancer. These patients have meager prognosis and short-term survival. Precise assessment of glomerular filtration rate is a fundamental aspect of clinical care in cancer patients. Cystatin C has been proposed to be superior to creatinine, a well-known marker of renal function. This study aimed to evaluate cystatin C as a marker of GFR calculation in CCA patients. Materials and Methods: One hundred thirty serum samples from CCA patients and 32 from controls were included in this study. Serum cystatin C was measured using immunoturbidity assay. Estimated glomerular filtration rate was calculated by three equations established by chronic kidney disease epidemiology collaboration (based on creatinine and/or cystatin C). Results: Serum cystatin C in CCA patients was higher than that of controls (p=0.0002). Cystatin C was positively correlated with BUN in CCA group (p=0.019). eGFR based on cystatin C and based on both cystatin C and creatinine in CCA was low with significantly different from those of control (p<0.001). Although there was no difference in eGFR using three equations in control, creatinine based eGFR was high with significantly different from eGFR based on cystatin C and on both creatinine and cystatin C in CCA (P=0.000). Proportion in each eGFR stage by three equations showed a high sensitivity with significantly different in CCA (p<0.05). Conclusion: There was a high sensitivity of cys C with significant difference between creatinine and/or cystatin C based eGFR in CCA patients. It should be taken into consideration of mild changes in eGFR by cystatin C which is important in managing drug dosage for CCA patients.

Corticosteroids significantly increase cystatin C levels in the plasma by promoting cystatin C production in rats

Background: Several studies have shown that non-renal factors such as corticosteroids may increase plasma cystatin C levels without affecting kidney function. However, the mechanisms underlying this are unclear. We hypothesized that corticosteroids may increase cystatin C levels in the plasma by promoting its production in tissues. In the present study, we aimed to test our hypothesis in rats by investigating the effect of corticosteroids on cystatin C production in tissues and the glomerular filtration rate (GFR), as measured by the gold standard method (i.e., inulin clearance). Results: Dexamethasone treatment was associated with much higher concentrations of cystatin C in all organ tissue homogenates tested. Dexamethasone increased plasma cystatin C levels in rats, without any decrease in renal inulin clearance. The impact of dexamethasone on plasma and organ tissue cystatin C levels was abolished by RU486, indicating the effect was glucocorticoid receptor-mediated. Conclusions: Our study provides direct evidence that corticosteroids may increase cystatin C levels in the plasma by promoting its production, without any decrease in GFR.

Agreement and Precision Analyses of Various Estimated Glomerular Filtration Rate Formulae in Cancer Patients

The accuracy of the estimated glomerular filtration rate (eGFR) in cancer patients is very important for dose adjustments of anti-malignancy drugs to reduce toxicities and enhance therapeutic outcomes. Therefore, the performance of eGFR equations, including their bias, precision, and accuracy, was explored in patients with varying stages of chronic kidney disease (CKD) who needed anti-cancer drugs. The reference glomerular filtration rate (GFR) was assessed by the ^99mTc-diethylene triamine penta-acetic acid (^99mTc-DTPA) plasma clearance method in 320 patients and compared with the GFRs estimated by i) the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, ii) the unadjusted for body surface area (BSA) CKD-EPI equation, iii) the re-expressed Modification of Diet in Renal Disease (MDRD) study equation with the Thai racial factor, iv) the Thai eGFR equation, developed in CKD patients, v) the 2012 CKD-EPI creatinine-cystatin C, vi) the Cockcroft-Gault formula, and vii) the Janowitz and Williams equations for cancer patients. The mean reference GFR was 60.5 ± 33.4 mL/min/1.73 m². The bias (mean error) values for the estimated GFR from the CKD-EPI equation, BSA-unadjusted CKD-EPI equation, re-expressed MDRD study equation with the Thai racial factor, and Thai eGFR, 2012 CKD-EPI creatinine-cystatin-C, Cockcroft-Gault, and Janowitz and Williams equations were -2.68, 1.06, -7.70, -8.73, 13.37, 1.43, and 2.03 mL/min, respectively, the precision (standard deviation of bias) values were 6.89, 6.07, 14.02, 11.54, 20.85, 10.58, and 8.74 mL/min, respectively, and the accuracy (root-mean square error) values were 7.38, 6.15, 15.97, 14.16, 24.74, 10.66, and 8.96 mL/min, respectively. In conclusion, the estimated GFR from the BSA-unadjusted CKD-EPI equation demonstrated the least bias along with the highest precision and accuracy. Further studies on the outcomes of anti-cancer drug dose adjustments using this equation versus the current standard equation will be valuable.

Mesenchymal Stem Cells: a Promising Therapeutic Tool for Acute Kidney Injury

Acute kidney injury (AKI) is a rapid loss of renal function. It has high mortality rates. Still, renal replacement therapy is considered the best solution for recovering AKI. This opens a line of thought to develop an alternative therapy for it without complications. Mesenchymal stem cells are considered a new therapy for treating kidney diseases. The aim of this work was to address the anti-apoptotic, antioxidative, and pro-angiogenic effects of adipose tissue-derived MSCs (AD-MSCs) and bone marrow-MSCs (BM-MSCs) for treating AKI. Adult male Wistar rats were assigned into nine groups (n = 10): (1) the control group; (2) the AKI group, receiving cisplatin; (3) the AKI group treated with AD-MSCs (1 × 10⁶); (4) the AKI group treated with AD-MSCs (2 × 10⁶); (5) the AKI group treated with AD-MSCs (4 × 10⁶); (6) the AKI group treated with losartan; (7) the AKI group treated with BM-MSCs (1 × 10⁶); (8) the AKI group treated with BM-MSCs (2 × 10⁶); and (9) the AKI group treated with BM-MSCs (4 × 10⁶). The results showed a significant rise in creatinine, urea, and cystatin C (cys C) levels and upregulation of p38 mRNA, whereas a significant decline in NAD(P)H quinone oxidoreductase 1 (NQO-1) protein and downregulation of B-cell lymphoma-2 (Bcl-2) mRNA and vascular endothelial growth factor (VEGF) mRNA were recorded in AKI. MSCs could improve renal functions manifested by decreased urea, creatinine, and cys C levels; downregulation of p38; and upregulation of Bcl-2 and VEGF. Moreover, MSC therapy could induce NQO-1 in the treated rats relative to the untreated rats. So, cell-based therapy can reduce AKI through the antioxidative, anti-apoptotic, and pro-angiogenic properties of MSCs. Therefore, the findings received in this attempt create a fertile base for the setup of cell therapy in patients with AKI.

Aberrant cystatin-C expression in blood from patients with breast cancer is a suitable marker for monitoring tumor burden

The present study was performed to evaluate the efficacy of circulating cystatin-C as a tumor monitoring biomarker at different clinical time points in patients with breast cancer over a long-term follow-up period. In addition, the secretory rate of circulating cystatin-C from cancer tissue was investigated by comparing the blood and tissue expression levels of cystatin-C. Blood samples from healthy volunteers (40 males and 40 females) were obtained at yearly health examinations if laboratory and imaging abnormalities were not detected. Blood samples from 34 patients with breast cancer were obtained at 205 different time points of clinical progression. Blood levels of cystatin-C were measured using ELISA and the tissue levels were measured using immunohistochemistry. No age-associated effect was observed in male and female blood cystatin-C levels. The positivity rate was 46% in patients (38/83) and 40% in samples collected at different time points (82/205). Blood cystatin-C levels were lowest following surgery compared with patients with systemic metastasis (P<0.001). The sensitivity, specificity and accuracy rates of ELISA were 53.6, 63.6 and 53.9%, respectively. The concordance rate between blood and tissue expression was 38%. The main reason for discordance between tissue and serum expression of cytostatin-C came from low serum positivity in samples showing tissue cytostatin-C (3/11, 27%). The specificity between cytostatin-C and CA-125 was highest in tumor absence state. In conclusion, elevated blood levels of cystatin-C were observed in 40% of breast cancer cases and were tumor-volume dependent. However, the concordance rate between tissue and blood was quite low, suggesting tumor heterogeneity of cystatin-C expression or co-acting pathway activation, such as cathepsin D. As one-third of breast cancer tissues express cystatin-C without cancer antigen 15-3 elevation, cystatin-C may represent a good tumor-monitoring marker in breast cancer.

Dexamethasone Modifies Cystatin C-Based Diagnosis of Acute Kidney Injury During Cisplatin-Based Chemotherapy

BACKGROUND/AIMS

Plasma cystatin C (pCysC) may be superior to serum creatinine (sCr) as a surrogate of GFR. However, the performance of pCysC for diagnosing acute kidney injury (AKI) after cisplatin-based chemotherapy is potentially affected by accompanying corticosteroid anti-emetic therapy and hydration.

METHODS

In a prospective observational study pCysC, sCr, urinary kidney injury molecule-1 (KIM-1), and urinary clusterin were measured over 2 weeks in 27 patients given first-cycle chemotherapy. The same variables were measured over 2 weeks in Sprague-Dawley rats given a single intraperitoneal injection of dexamethasone, cisplatin, or both, and in controls.

RESULTS

In patients, pCysC increases were greater than sCr 41% vs. 16%, mean paired difference 25% (95% CI: 16-34%)], relative increases were ≥ 50% in 9 patients (35%) for pCysC compared with 2 (8%) for sCr (p = 0.04) and increases in sCr were accompanied by increased KIM-1 and clusterin excretion, but increases in pCysC alone were not. In rats, dexamethasone administration produced dose-dependent increases in pCysC (and augmented cisplatin-induced increases in pCysC), but did not augment histological injury, increases in sCr, or KIM-1 and clusterin excretion.

CONCLUSIONS

In the presence of dexamethasone, elevation of pCysC does not reliably diagnose AKI after cisplatin-based chemotherapy.

Changes in blood concentrations of trace metals in cancer patients receiving cisplatin-based chemotherapy

The administration of cisplatin (CDDP) may influence trace metal concentrations in body fluids. In order to test this hypothesis, the blood concentrations of trace metals were determined during the present study in eight Japanese esophageal and lung cancer patients receiving CDDP-based chemotherapy. The levels of manganese, iron (Fe), cobalt, copper, zinc (Zn), platinum and lead in the plasma were determined by inductively coupled plasma-mass spectrometry. In addition, the serum levels of Fe, transferrin and ferritin were evaluated. The baseline plasma concentration of Fe in patients with esophageal cancer was significantly lower than that in lung cancer patients (P=0.011), although there were no significant differences identified with respect to the plasma levels of other trace metals. The data obtained from six fasting patients without blood transfusion demonstrated that plasma concentrations of Fe increased 3.5-fold soon after CDDP treatment and returned to baseline levels ~10 days after therapy. The excessive Fe levels in the bloodstream induced changes in serum ferritin and transferrin levels. Furthermore, serum Zn levels increased 1.8-fold in the 1-3 days following CDDP treatment, and serum cystatin C levels transiently increased. These findings indicate that serum Fe and Zn levels may be useful to understanding the physiological responses in the early stages of CDDP-based chemotherapy, which may be associated with systemic inflammation and/or tissue distribution of CDDP.

In vivo pharmacokinetic and tissue distribution investigation of sustained-release cisplatin implants in the normal esophageal submucosa of 12 beagle dogs

PURPOSE

The aim of this study was to clarify the pharmacokinetic, tissue distribution, hematologic, and histopathologic characteristics of sustained-release cisplatin from implants [CDDP-nanoparticle (NP) implants].

METHODS

Eighteen dogs (six hybrids and twelve beagles) were divided into three groups. In Group A, the six hybrid dogs were intravenously administered 20 mg CDDP via a hind limb vein. In Groups B and C, CDDP-NP implants containing CDDP doses of 40 and 60 mg, respectively, were embedded into the esophageal submucosa of beagles via painless gastroscopy with an endoscopic booster. Graphite frameless atomic absorption spectrophotometry was used to measure total platinum in plasma and tissues at various timepoints. In addition, free platinum levels in Group B were determined using inductively coupled plasma mass spectrometry. Toxicologic evaluation was also conducted.

RESULTS

Pharmacokinetic results indicated that the CDDP-NP implant could achieve a smooth pharmacokinetic curve, with the plasma invalid concentration reached after almost 480 h, which is approximately ten times longer than that of standard CDDP (48 h). The peak time, peak concentration, clearance, elimination half-life, area under the curve, volume of distribution at steady state, and mean residence time of Groups B and C were 494 and 211, 0.39 and 0.42, 0.044 and 0.059, 80.11 and 87.70, 44 and 49, 38.8 and 57.9, and 12.29 and 12.39 times those of Group A, respectively (all P < 0.05). The ratio of free/total platinum concentration was 2.0-3.1% in plasma, 14.2% in liver tissue, and 14.3% in kidney tissue. Tissue distribution studies showed that the highest platinum concentrations were found in the esophagus, followed by the kidney and liver. Compared with pre-implantation (day 0), there were no significant differences in most hematological indicators in Groups B and C (P > 0.05). Furthermore, histopathologic examination of the kidneys of dogs from Group C revealed no significant kidney damage. Unlike the intravenous CDDP group (Group A), no animals in the implantation groups showed any clinical signs of toxicity.

CONCLUSION

CDDP-NP implants can be used to achieve a smooth pharmacokinetic curve and higher drug concentration, as well as a longer mean residence time at the implantation site, with reduced side effects compared with intravenous CDDP.

Effect of dexamethasone on extracellular secretion of cystatin C in cancer cell lines

The aim of the present study was to investigate dexamethasone (DEX)-induced secretion of cystatin C (Cys C) and the effect of cisplatin (CDDP) and 5-fluorouracil (5-FU) on Cys C secretion in human cancer cell lines. KYSE150, A549 and Caki-2 human cancer cell lines were cultured on plastic dishes and treated with DEX (100 nM) for 24, 48 and 72 h. KYSE150 cells were co-treated with DEX, CDDP (10 μM), and 5-FU (2 μM). The effects of DEX, CDDP and 5-FU on cell viability were evaluated. Results showed Cys C secretion levels in the culture medium of DEX-treated KYSE150 cells to be 1.8- to 2.3-fold higher compared to those in the culture medium of control cells. A similar tendency was observed in A549 cells at all the time points, whereas a significant increase in the Cys C secretion by Caki-2 cells was observed only 24 h after DEX treatment. Regarding KYSE150 cells, the secretion of Cys C was also enhanced by co-treatment of CDDP or 5-FU with DEX, although it was not affected by the co-administration of DEX and mifepristone, a glucocorticoid receptor antagonist. At concentrations that are typically used in esophageal cancer chemotherapy, CDDP and 5-FU demonstrated a moderate level of cytotoxicity in KYSE150 cells in contrast to DEX. These findings suggested that DEX has the potential to enhance the extracellular secretion of Cys C in esophageal cancer cells, possibly due to the transcriptional regulation mediated by glucocorticoid receptor activity.