Proteasome Subunit Alpha Type-7 Expression Suppresses Cutaneous Squamous Cell Carcinoma Progression by Inhibiting Cancer-associated Cytokines.

BACKGROUND/AIM: Cutaneous squamous cell carcinoma (cSCC) is a common non-melanoma skin cancer, and its incidence is increasing. Proteasome subunit alpha type-7 (PSMA7) has been found to be aberrantly expressed in several cancers. However, whether it functions as a tumor suppressor or oncogene in the pathogenesis of cancers, particularly cSCC, remains controversial. Here, we aimed to investigate the functions of PSMA7 in cSCC pathogenesis. PATIENTS AND METHODS: Clinicopathological characteristics were evaluated in 131 patients with cSCC using tissue sections. The expression of PSMA7, nucleotide-binding oligomerization domain-containing protein 1 (NOD1), and mitochondrial antiviral signaling protein (MAVS) was determined in cSCC tissue sections using immunohistochemical staining. The effect of PSMA7 expression on the biological behavior of cSCC cells was investigated in vitro. RESULTS: High immunoreactivity of PSMA7 (high-PSMA7) was detected in 53 (40.5%) patients with cSCC and was significantly associated with histologic grade (p=0.008) and favorable recurrence-free survival (p=0.018). The expression of PSMA7 and NOD1 (p=0.026) and MAVS (p=0.032) was negatively correlated in cSCC tissues. Contrary to the results of the cohort study, cell viability and invasiveness significantly decreased after PSMA7 down-regulation in cSCC cells in vitro. mRNA expression of tumor necrosis factor-alpha, interleukin-1 alpha (IL-1α), IL-6, and IL-8 were significantly increased after PSMA7 down-regulation in cSCC cells (all p=0.002). CONCLUSION: PSMA7-mediated degradation of NOD1 and MAVS as well as the subsequent reduction of the cancer-associated cytokine network may be a crucial mechanism of the antitumoral function of PSMA7 in patients with cSCC.

A nomogram combining clinical factors and biomarkers for predicting the recurrence of high-risk cutaneous squamous cell carcinoma.

BACKGROUND: Although determining the recurrence of cutaneous squamous cell carcinoma (cSCC) is important, currently suggested systems and single biomarkers have limited power for predicting recurrence. OBJECTIVE: In this study, combinations of clinical factors and biomarkers were adapted into a nomogram to construct a powerful risk prediction model. METHODS: The study included 145 cSCC patients treated with Mohs micrographic surgery. Clinical factors were reviewed, and immunohistochemistry was performed using tumor tissue samples. A nomogram was constructed by combining meaningful clinical factors and protein markers. RESULTS: Among the various factors, four clinical factors (tumor size, organ transplantation history, poor differentiation, and invasion into subcutaneous fat) and two biomarkers (Axin2 and p53) were selected and combined into a nomogram. The concordance index (C-index) of the nomogram for predicting recurrence was 0.809, which was higher than that for the American Joint Committee on Cancer (AJCC) 7th, AJCC 8th, Brigham and Women's Hospital, and Breuninger staging systems in the patient data set. CONCLUSION: A nomogram model that included both clinical factors and biomarkers was much more powerful than previous systems for predicting cSCC recurrence.

Understanding the effects of potassium ferricyanide on lead hydride formation in tetrahydroborate system and its application for determination of lead in milk using hydride generation inductively coupled plasma optical emission spectrometry.

To understand the formation of plumbane in the Pb(II)-NaBH4-K3Fe(CN)6 system, the intermediate products produced in the reaction of lead(II) and NaBH4 in the presence of K3Fe(CN)6 were studied. The produced plumbane and elemental lead were measured through continuous flow hydride generation (HG)-inductively coupled plasma optical emission spectrometry (ICP OES) and X-ray diffraction spectrometry techniques, respectively. Based on the experimental results, the explanations can be depicted in the following steps: (1) plumbane and black lead sediment (black Pb) are formed in the reaction of lead(II) and NaBH4; (2) the black Pb is oxidized by K3Fe(CN)6 to form Pb2[Fe(CN)6], which further reacts with NaBH4 to form more plumbane and black Pb; and (3) another round starts in which the produced black Pb from the step 2 is then oxidized continuously by K3Fe(CN)6 to form more Pb2[Fe(CN)6] complex, which would produce more plumbane. In short, the black Pb and Pb2[Fe(CN)6] complex are the key intermediate products for the formation of plumbane in the Pb(II)-NaBH4-K3Fe(CN)6 system. Based on the enhancement effect of potassium ferricyanide and potassium ferrocyanide, a method was developed to analyze lead in milk with HG-ICP OES technique. The detection limit of the method was observed as 0.081 µg L(-1). The linearity range of lead was found between 0.3 and 50,000 µg L(-1) with correlation coefficient of 0.9993. The recovery of lead was determined as 97.6% (n=5) for adding 10 µg L(-1) lead into the milk sample.

Interface of on line coupling capillary electrophoresis with hydride generation electrothermal atomic absorption spectrometry and its application to arsenic speciation in sediment.

A novel interface for on line coupling capillary electrophoresis with hydride generation electrothermal atomic absorption spectrometry (CE-HG-ETAAS) has been developed. The interface performance was examined in detail. The technique could be used to convert arsenic compounds from CE separation to corresponding volatile hydrides determined by HG-ETAAS. This paper aims to explore the best condition in the speciation analysis of inorganic arsenic by using CE-HG-ETAAS. The application of the developed CE-HG-ETAAS to inorganic arsenic speciation in sediment was investigated. The detection limits of As(III) and As(V) were 135 ng/g and 160 ng/g, respectively. Relative standard deviations of arsenic speciation were better than 2%. The recoveries of As(III) and As(V) in the sample with spiking concentration of 2500 ng/g As(III) and 5000 ng/g As(V) were 97.6% and 96.7%, respectively.

Study of the binding equilibrium between Zn(II) and HSA by capillary electrophoresis-inductively coupled plasma optical emission spectrometry.

A new method has been developed for following the interaction between zinc ion and human serum albumin (HSA) by capillary electrophoresis-inductively coupled plasma optical emission spectrometry. Under optimized experimental conditions, the detection limit (3σ) for free Zn(2+) ion was found to be 1.34 µM by running 11 replicates of the reagent blank. The RSD was less than 3% and the recovery was more than 98.13%. The linear range of zinc ion concentration was between 5.1 µM and 0.3M. The measured Zn(II)-HSA combination values of n(1) and K(1) for primary binding of Zn(2+) to HSA were 1.09 and 2.29×10(5) L mol(-1), respectively. The measured values of n(2) and K(2) for the non-specific binding of Zn(2+) to HSA were 8.96 and 6.65×10(3) L mol(-1), respectively. This new method allows rapid analysis of a small amount of sample, simple operation, while avoiding long periods of dialysis and eliminating interference from other metal ions. This method provides a reliable and convenient new way for studying interactions between metal ions and biomolecules.

Cold vapor generation interface for mercury speciation coupling capillary electrophoresis with electrothermal quartz tube furnace atomic absorption spectrometry: determination of mercury and methylmercury.

A novel on-line coupled capillary electrophoresis (CE) cold vapor generation (CVG) with electrothermal quartz tube furnace atomic absorption spectrometry (EQTF-AAS) system for mercury speciation has been developed. The mercury species (inorganic mercury and methylmercury) were completely separated by CE in a 80 cm length x 100 microm i.d. fused-silica capillary at 20 kV and using a buffer of 100 mM boric acid and 10% (v/v) methanol (pH 8.30). The effects of the inner diameter of quartz tube, the acidity of HCl, the NaBH(4) concentration and N(2) flow rate on Hg signal intensity were investigated. Speciation of mercury was highlighted using CE-CVG-EQTF-AAS. The detection limits of methylmercury and mercury were 0.035 and 0.027 microg mL(-1), respectively. The precisions (RSDs) of peak height for six replicate injections of a mixture of 10 microg mL(-1) (as Hg) were better than 4%. The interface was used for speciation analysis of mercury in dry goldfish muscle.

Determination of free calcium and calcium-containing species in human plasma by capillary electrophoresis-inductively coupled plasma optical emission spectrometry.

A new method for the determination of free calcium concentration in human plasma was developed by online coupling capillary electrophoresis (CE) with inductively coupled plasma optical emission spectrometry (ICP-OES). Baseline separation of calcium-containing species was achieved by CE-ICP-OES in a 120-cm-long capillary with 100-microm internal diameter, at 20 kV applied voltage, with a 30 mmol/L Tris-HCl buffer at pH 7.4. A total of eight calcium-containing species were found in human plasma; the concentration of free calcium ion was found to be 41.9 mg/L. The concentrations of calcium for other seven calcium species, estimated from the calibration against Ca(2+) standard, were 3.14-15.6 mg/L. The precision (RSD, n = 10) ranged from 1.2 to 2.7% for the migration time and 2.8 to 3.9% for the peak area. The developed method was also applied to analyze plasma samples with recovery ranged from 94.5 to 102% for samples spiked with 40 mg/L free Ca(2+) ion.

Speciation of magnesium in rat plasma using capillary electrophoresis-inductively coupled plasma-atomic emission spectrometry.

A new method for speciation analysis of magnesium species and quantification of free magnesium concentrations in rat plasma was developed by on-line coupling of CE with inductively coupled plasma-atomic emission spectrometry (ICP-AES). Baseline separation of seven magnesium species was achieved by using a 120 cm (100 microm internal diameter) fused-silica capillary, a 20 kV separation voltage and a solution of 50 mmol/L NaAc-HAc (pH 5.5) as electrolyte buffer. CE-ICP-AES analysis of a rat plasma sample showed the presence of seven magnesium species, one of which was identified as free Mg2+ ion by spiking a Mg2+ standard; the migration time of the Mg2+ peak in the standard and the spiked sample matched with each other. One protein-bound magnesium species in rat plasma is associated with albumin, and the other three species are combined with globulin. The concentration of free magnesium in the plasma was 14.0 mg/L. The other six magnesium species were estimated to be 4-15 mg/L. RSDs of migration time and peak area for the magnesium species from ten replicates were less than 5%. The developed method was also applied to speciation analysis of magnesium species in spiked plasma samples. The recoveries of the free magnesium species in four samples ranged from 95.8 to 103.8%.