Changes in Serum Trace Element Concentrations Before and After Surgery in Resectable Breast Cancer.

BACKGROUND/AIM: Minerals and trace elements (TEs) play vital roles in normal biological functions and in all cancers. Breast carcinoma is the most commonly occurring cancer in women. The aim of this study was to evaluate changes in TE levels before and after breast cancer surgery and the clinical utility and reliability of TE levels assayed using inductively coupled plasma mass spectrometry (ICP-MS). PATIENTS AND METHODS: Thirteen patients with ductal carcinoma in situ (DCIS) and 34 with invasive ductal carcinoma (IDC) treated with planned surgery were enrolled between August 2017 and February 2019. Blood samples were collected before and the day after resection of the primary tumor. All enrolled patients received mastectomy or quadrantectomy and axillary lymph node dissection/biopsy. Serum TE concentrations were determined using ICP-MS. RESULTS: Changes in boron, titanium, vanadium, chromium, copper, zinc, and selenium levels from before to after surgery differed between IDC and DCIS patients. Boron and copper levels before surgery and changes in titanium, vanadium, and chromium before and after surgery are potential predictors distinguishing DCIS from IDC. Subset analysis showed that chromium is a potential biomarker for luminal subtype, while titanium and chromium are potential biomarkers for pathological staging. CONCLUSION: Changes in serum TEs before and after surgery may help with diagnosis and staging of breast cancer and in establishing TE supplementation protocols.

Regioselective monosulfation and disulfation of the phytoestrogens daidzein and genistein by human liver sulfotransferases.

Regioselective sulfation of the phytoestrogens daidzein (DZ, 7,4'-dihydroxyisoflavone) and genistein (GS, 5,7,4'-trihydroxyisoflavone) was investigated using human liver cytosol and purified recombinant human sulfotransferase (SULT) isoforms, SULT1A1, SULT1A3, SULT2A1, and SULT1E1. 7-Position-preferential sulfation of DZ and GS was observed in human hepatic cytosols from 3 male and 3 female subjects. Average ratios for 7- to 4'-sulfate formation were 4.5:1 from DZ and 8.4:1 from GS in these human liver cytosols. Apparent K(m) values for the 7- and 4'-sulfation of DZ and GS by these cytosols were similar and in a range from 0.46 to 0.66 microM. All recombinant human SULTs had activity for 7- and 4'-sulfation of these phytoestrogens except for 7-sulfating activity of SULT1A3. SULT1A1 and SULT1E1 exhibited much higher catalytic efficiency, k(cat)/K(m), for 7- and 4'-sulfation of these substrates than did the other two, SULT1A3 and SULT2A1. SULT1A1 showed K(m) values of 0.47 and 0.52 microM for the mono-sulfation of DZ and GS, respectively, which were very similar to those of human cytosol. The observed k(cat)/K(m) indicated that SULT1A1 catalyzed 7-sulfation of DZ and GS at rates 4.4- and 8.8-fold higher, respectively, than such 4'-sulfation. However, with SULT1E1, catalytic efficiency was very similar for the sulfation of both positions. These data strongly suggest that SULT1A1 plays a major role in monosulfation of the phytoestrogens and determines the regioselectivity of sulfation in human hepatic cytosol. A kinetic study for 7,4'-disulfate formation of DZ and GS from their 7- and 4'-monosulfates indicated that SULT1E1 most efficiently catalyzed both reactions among human SULTs.