Chemoradiotherapy and Lymph Node Metastasis Affect Dendritic Cell Infiltration and Maturation in Regional Lymph Nodes of Laryngeal Cancer.

Dendritic cells (DCs) are the most specialized antigen-presenting cells, and lymph nodes (LNs) play an important role in the DC-mediated T-cell response. We evaluated the infiltration of CD1a-positive DCs (CD1a-DCs), i.e., immature DCs, and S100-positive dendritic cells (S100-DCs), a mixture of immature and mature DCs, in 73 cases of laryngeal cancer and its regional LNs. Among them, 31 patients underwent radiotherapy (RT) or chemoradiotherapy (CRT) prior to surgery. No significant difference was found for CD1a-DC infiltration in the primary tumors, metastatic LNs and non-metastatic LNs, while S100-DCs were significantly fewer in number in the primary tumors and metastatic LNs compared to non-metastatic LNs. The cases which showed a high infiltration of S100-DCs in the metastatic LNs appeared to show a favorable prognosis, although statistical significance was not reached. In the RT/CRT group, the infiltration of the CD1a-DCs and S100-DCs was less in the primary tumors and metastatic LNs compared to the treatment-naive group. Conversely, the RT/CRT group showed higher CD1a-DC and S100-DC numbers in the non-metastatic LNs compared to the treatment-naïve group. Thus, DC maturation in metastatic LNs plays an important role in tumor immunity in laryngeal cancer, and the infiltration of DCs into the primary tumor and metastatic LNs is impaired by RT/CRT.

Collision tumor of a papillary and follicular thyroid carcinoma: a case report.

BACKGROUND: Papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) are common differentiated thyroid cancers, but the detection of a collision tumor is an extremely rare event. CASE PRESENTATION: The patient was a 69-year-old Japanese female with multiple cervical lymph node swellings and a thyroid tumor. Preoperative fine needle aspiration cytology of the enlarged lymph node revealed a cytological diagnosis of papillary thyroid carcinoma (PTC). A total thyroidectomy, right cervical dissection and paratracheal dissection were performed. Histopathological and immunohistochemical analyses of resected specimens revealed a collision tumor of PTC and FTC. Multiple metastases of papillary carcinoma were found in the dissected lymph nodes. In the PTC lesion, IHC for BRAF (V600E) was positive but negative for the FTC lesion. Genetic analyses further revealed a TERT promoter C228T mutation in PTC and a NRAS codon 61 mutation in FTC. The patient died of recurrent cancer 8 months after surgery. CONCLUSIONS: A case of a collision tumor of PTC and FTC is very rare, and even fewer cases have been subjected to genetic scrutiny. The present case was successfully diagnosed by pathological examination using immunohistochemical and genetic analyses. The TERT promoter mutation in the PTC lesion was consistent with the aggressive behavior of the cancer.

Association of plasma concentration of 4ß-hydroxycholesterol with CYP3A5 polymorphism and plasma concentration of indoxyl sulfate in stable kidney transplant recipients.

Several studies have shown that renal failure decreases CYP3A activity and that uremic toxins may play a role via transcriptional or translational modifications of cytochrome P450 (P450) enzymes and direct inhibition of P450-mediated metabolism. In this study, we evaluated the relationship between CYP3A activity (using plasma concentration of 4ß-hydroxycholesterol as a biomarker) and clinical characteristics including plasma concentrations of indoxyl sulfate (3-INDS) and indole-3-acetic acid (3-IAA) in stable kidney transplant recipients. Forty-five Japanese kidney transplant recipients who underwent transplantation more than 90 days prior to the study were included. Morning blood samples were collected and plasma concentrations of 4ß-hydroxycholesterol, 3-INDS, and 3-IAA were measured. Plasma concentrations of 4ß-hydroxycholesterol were 57.1 ± 11.2, 42.1 ± 11.8, and 34.5 ± 7.3 ng/ml in recipients with CYP3A5*1/*1 (n = 5), *1/*3 (n = 15), and *3/*3 (n = 25) genotypes, respectively, with significant differences between three genotypes. A significant correlation was observed between plasma concentrations of 4ß-hydroxycholesterol and 3-INDS but not 3-IAA. Multiple regression analysis identified the number of CYP3A5*3 alleles in genotype, plasma concentration of 3-INDS, and body weight as independent variables associated with plasma concentration of 4ß-hydroxycholesterol. In conclusion, these results suggest that CYP3A5 polymorphism and plasma concentration of 3-INDS may account for the interindividual variability of CYP3A activity, and that plasma concentration of 3-INDS may partially explain the gap in CYP3A activity that cannot be explained by genetic contribution in patients with renal failure.

Relationship between plasma mid-regional pro-adrenomedullin level and resistance to antihypertensive therapy in stable kidney transplant recipients.

We investigated the relationship between plasma mid-regional pro-adrenomedullin (MR-proADM)-like immunoreactive substance (IS) level and clinical characteristics associated with renal failure or resistance to antihypertensive therapy in stable kidney transplant recipients. Forty-six Japanese kidney transplant recipients who underwent transplantation more than 90 days prior to the study were included. To evaluate resistance to antihypertensive therapy, we calculated the treatment intensity score of the antihypertensive drugs in each recipient. Morning blood samples were collected and plasma MR-proADM-IS levels were measured using an enzyme immunoassay. A significant correlation was observed between plasma MR-proADM-IS level with creatinine clearance or treatment intensity score. Multiple regression analysis identified plasma MR-proADM level and body mass index as significant independent factors associated with treatment intensity score. Plasma MR-proADM level may be a useful biomarker indicating the degree of resistance to antihypertensive therapy.

Significant increase in plasma 4ß-hydroxycholesterol concentration in patients after kidney transplantation.

Several previous studies have shown that renal failure decreases not only renal elimination but also metabolic clearance of drugs, particularly those metabolized by CYP3A. However, whether recovery of renal function results in recovery of hepatic CYP3A activity remains unknown. In this study, we evaluated the effect of renal function on CYP3A activity after kidney transplantation in patients with end-stage renal disease (ESRD) by measuring the change in CYP3A activity using plasma concentration of 4ß-hydroxycholesterol as a biomarker. The study enrolled 13 patients with ESRD who underwent the first kidney allograft transplantation. Morning blood samples were collected before and 3, 7, 10, 14, 21, 30, 60, 90, 120, 150 and 180 days after kidney transplantation. Plasma concentration of 4ß-hydroxycholesterol was measured using GC-MS. Compared with before kidney transplantation, creatinine clearance increased significantly from day 3 after kidney transplantation and stabilized thereafter. Plasma concentration of 4ß-hydroxycholesterol was elevated significantly on days 90 and 180 after kidney transplantation. In conclusion, this study suggests the recovery of CYP3A activity with improvement in renal function after kidney transplantation in patients with ESRD.

Association of sustained high plasma trough concentration of voriconazole with the incidence of hepatotoxicity.

BACKGROUND: Therapeutic drug monitoring (TDM) of voriconazole is important to optimize efficacy and to minimize toxicity and intolerance. In this study, we evaluated the effect of sustained high plasma trough concentration of voriconazole on the incidence of hepatotoxicity in hospitalized Japanese patients. METHODS: Thirty-nine patients were divided into 3 groups according to trough concentrations in two consecutive TDMs: <4 µg/ml in the first TDM (group A, n=25), >4 µg/ml in the first and <4 µg/ml in the second TDM (group B, n=8), and >4 µg/ml in both first and second TDMs (group C, n=6). RESULTS: Incidences of hepatotoxicity in groups A, B and C were 16.0, 25.0 and 83.3%, and significant differences were observed between groups A and C and groups B and C. Multiple logistic regression analysis identified the classification into groups A, B and C as an independent variable of hepatotoxicity. CONCLUSIONS: These results suggest that sustained high trough concentration of voriconazole may increase the risk of hepatotoxicity, and decreasing trough concentration to <4 µg/ml by dose adjustment after the initial TDM may reduce the incidence of hepatotoxicity in patients treated with voriconazole.

Significant decrease in plasma midregional proadrenomedullin level in patients with end-stage renal disease after living kidney transplantation.

Impaired renal function has been suggested to significantly impact plasma midregional proADM (MR-proADM) level. The aim of this study was to assess whether improvement of renal function after living kidney transplantation has an impact on plasma MR-proADM-like immunoreactive substance (IS) level. Eleven patients with end-stage renal disease (ESRD) who were scheduled to undergo the first living kidney allograft transplantation were enrolled. Plasma MR-proADM-IS levels were measured before and 3, 7, 10, 14, 21, 30, 60 and 90 days after kidney transplantation. Plasma MR-proADM-IS level decreased significantly from day 3 after kidney transplantation compared to before kidney transplantation. A significant negative correlation was observed between creatinine clearance and plasma MR-proADM-IS level from before to 90 days after kidney transplantation (rs=-0.70, p<0.0001). These results suggest that recovery of kidney function after kidney transplantation may lead to decrease in plasma MR-proADM level in patients with ESRD, and that plasma MR-proADM level may depend largely on renal function.

Development and clinical application of an enzyme immunoassay for the determination of midregional proadrenomedullin.

Adrenomedullin (ADM) is a 52-amino acid peptide with a variety of physiologic functions such as immunomodulating activity, direct bactericidal activity, maintenance of renal homeostasis, and vasodilatory activity. Midregional proADM (MR-proADM) is derived from a larger 185-amino acid precursor peptide, prepro-adrenomedulin (preproADM), by posttranslational processing. It is suggested to be co-synthesized with ADM in equimolar amounts and has the advantages over ADM in having a longer half-life, no bioactivity, and no binding to protein. Therefore, MR-proADM serves as a surrogate for ADM secretion. In this study, we attempted to develop an enzyme immunoassay (EIA) for quantifying MR-proADM-like immunoreactive substance (IS), which is applicable for monitoring plasma MR-proADM levels. By using ß-d-galactosidase-labeled preproADM(83-94) as a marker antigen, anti-rabbit IgG-coated immunoplate as a bound/free separator, and 4-methylumbelliferyl-ß-d-galactopyranoside as a fluorogenic substrate, a sensitive and specific EIA was developed for the quantification of MR-proADM-IS in human plasma. The lower limit of quantification was 0.032 pmol/well, and the steep competitive inhibition EIA calibration curve obtained was linear between 0.16 and 10 nmol/L. By using human plasma samples containing 0.2 and 2.0 nmol/L of MR-proADM, the interassay coefficients of variation (reproducibility) were 10.78% and 8.83%, respectively, and intraassay coefficients were 3.91% and 7.81%. Plasma MR-proADM-IS level was significantly higher in patients with chronic renal failure (1.39 ± 0.50 nmol/L) compared with healthy subjects (0.19 ± 0.07 nmol/L). These results suggest that our EIA may be useful to evaluate plasma MR-proADM levels as a biomarker in various clinical settings.

Is peak concentration needed in therapeutic drug monitoring of vancomycin? A pharmacokinetic-pharmacodynamic analysis in patients with methicillin-resistant staphylococcus aureus pneumonia.

BACKGROUND: We analyzed the pharmacokinetic-pharmacodynamic relationship of vancomycin to determine the drug exposure parameters that correlate with the efficacy and nephrotoxicity of vancomycin in patients with methicillin-resistant Staphylococcus aureus pneumonia and evaluated the need to use peak concentration in therapeutic drug monitoring (TDM). METHODS: Serum drug concentrations of 31 hospitalized patients treated with vancomycin for methicillin-resistant S. aureus pneumonia were collected. RESULTS: Significant differences in trough concentration (Cmin)/minimum inhibitory concentration (MIC) and area under the serum concentration-time curve (AUC0-24)/MIC were observed between the response and non-response groups. Significant differences in Cmin and AUC0-24 were observed between the nephrotoxicity and non-nephrotoxicity groups. Receiver operating characteristic curves revealed high predictive values of Cmin/MIC and AUC0-24/MIC for efficacy and of Cmin and AUC0-24 for safety of vancomycin. CONCLUSIONS: These results suggest little need to use peak concentration in vancomycin TDM because Cmin/MIC and Cmin are sufficient to predict the efficacy and safety of vancomycin.

Establishment and clinical application of a highly sensitive enzyme immunoassay for determination of N-acetyl-seryl-aspartyl-lysyl-proline.

N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) is a natural inhibitor of pluripotent hematopoietic stem cell proliferation and is normally found in human plasma. Because AcSDKP is hydrolyzed by the N-terminal active site of angiotensin converting enzyme and partially eliminated in urine, its plasma level is a result of a complex balance between its production, hydrolysis by ACE, and renal elimination. In this study, we attempted to establish an enzyme immunoassay (EIA) for quantifying AcSDKP-like immunoreactive substance (IS), which is applicable for monitoring plasma AcSDKP levels in healthy subjects and patients with chronic renal failure. Using ß-D-galactosidase-labeled Gly-γAbu-SDKP as a marker antigen, an anti-rabbit IgG-coated immunoplate as a bound/free separator and 4-methylumbelliferyl-ß-D-galactopyranoside as a fluorogenic substrate, a highly sensitive and specific EIA was developed for the quantification of AcSDKP-IS in human plasma. The lower limit of quantification was 0.32 fmol/well, and the sharp inhibition competitive EIA calibration curve obtained was linear between 8.0 and 513 fmol/ml. This EIA was so sensitive that only 10 µl plasma sample was required for a single assay. The coefficients of variation (reproducibility) for human plasma concentrations of 0.2 and 2.1 pmol/ml were 7.2 and 7.7%, respectively, for inter-assay and 13.3 and 7.8% for intra-assay comparisons. Plasma AcSDKP-IS level was significantly higher in patients with chronic renal failure (0.92 ± 0.39 pmol/ml) compared with healthy subjects (0.29 ± 0.07 pmol/ml). These results suggest that our EIA may be useful to evaluate plasma AcSDKP level as a biomarker in various patients.