Expression of S100P protein correlates with and contributes to the tumorigenic capacity of HeLa cervical carcinoma cells

Tumor growth is associated with multiple changes at the gene expression level. Recognition of the genes differentially expressed between the cellular populations at various degrees of malignancy may provide valuable clues towards the identification of clinically useful diagnostic markers and/or therapeutic targets. In the present study, we used suppression subtractive PCR to identify differentially expressed genes with possible relevance for control of tumorigenic potential using two cervical carcinoma cell lines of the common HeLa origin, but of different capacity to generate tumors in nude mice. Screening of the subtracted libraries resulted in isolation of several known as well as novel genes including the gene encoding S100P calcium-binding protein that belongs to S100 family, whose members can bind and modulate effector proteins in a calcium-dependent manner. Expression of S100P was further studied in the context of different culture conditions and was found to correlate with the tumorigenic phenotype of the somatic cell hybrids between HeLa and normal human fibroblasts. Moreover, S100P was highly expressed in a number of tumorigenic cell lines derived from colorectal and breast carcinoma, suggesting that it is not restricted to a particular tumor type. Functional involvement of S100P in tumor growth was evaluated using tumor xenografts produced from the cells transfected with the full-length S100P cDNA. The results showed that S100P can positively affect anchorage-independent growth of the transfected cells and improve tumor formation in nude mice, suggesting that it actively participates in the control of the tumorigenic potential in vivo.     

New probabilistic risk assessment of ethylhexyl methoxycinnamate: Comparing the genotoxic effects of trans‐ and cis‐EHMC

Ethylhexyl methoxycinnamate (EHMC) is a widely used UV filter present in a large number of personal care products (PCPs). Under normal conditions, EHMC occurs in a mixture of two isomers: trans‐EHMC and cis‐EHMC in a ratio of 99:1. When exposed to sunlight, the trans isomer is transformed to the less stable cis isomer and the efficiency of the UV filter is reduced. To date, the toxicological effects of the cis‐EHMC isomer remain largely unknown. We developed a completely new method for preparing cis‐EHMC. An EHMC technical mixture was irradiated using a UV lamp and 98% pure cis‐EHMC was isolated from the irradiated solution using column chromatography. The genotoxic effects of the isolated cis‐EHMC isomer and the nonirradiated trans‐EHMC were subsequently measured using two bioassays (SOS chromotest and UmuC test). In the case of trans‐EHMC, significant genotoxicity was observed using both bioassays at the highest concentrations (0.5 ‐ 4 mg mL^?1). In the case of cis‐EHMC, significant genotoxicity was only detected using the UmuC test at concentrations of 0.25 ‐ 1 mg mL^?1. Based on these results, the NOEC was calculated for both cis‐ and trans‐EHMC, 0.038 and 0.064 mg mL^?1, respectively. Risk assessment of dermal, oral and inhalation exposure to PCPs containing EHMC was carried out for a female population using probabilistic simulation and by using Quantitative in vitro to in vivo extrapolation (QIVIVE). The risk of cis‐EHMC was found to be ～1.7 times greater than trans‐EHMC. In the case of cis‐EHMC, a hazard index of 1 was exceeded in the 92nd percentile. Based on the observed differences between the isomers, EHMC application in PCPs requires detailed reassessment. Further exploration of the toxicological effects and properties of cis‐EHMC is needed in order to correctly predict risks posed to humans and the environment. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 569–580, 2017.     

Characterization of Expression in Mice of a Transgene Containing 3.3?kb of the Human Lactase-Phlorizin Hydrolase (LPH) 5�� Flanking Sequence

Background and Aim

The regulation of human intestinal lactase-phlorizin hydrolase remains incompletely understood. One kb of pig and 2 kb of rat 5??-flanking sequence controls correct tissue, cell, topographic, and villus LCT expression. To gain insight into human LCT expression, transgenic mouse lines were generated from 3.3 kb of human LPH 5?? flanking sequence from a lactase persistent individual fused to a human growth hormone (hGH) reporter bounded by an insulator.

Methods

Four lines were identified in which reporter expression was specifically detectable in the intestine and no other organ, two of which demonstrated hGH expression specific to small and large intestine. Quantitative RT-PCR was carried out on proximal to distal segments of small intestine at fetal days 16.5 and 18.5 and at birth, postnatal days 7 and 28 in line 22.

Results

In fetal intestine, hGH expression demonstrated a proximal to distal gradient similar to that in native intestine. There was no significant difference between hGH expression levels at 7 and 28 days in segment 3, the midpoint of the small intestine, where expression of endogenous lactase is maximal at 7 days and declines significantly by 28 days. Distal small intestine displayed high levels of hGH expression in enteroendocrine cells, which were shown to be a subset of the PYY cells.

Conclusions

Thus, a 3.3-kb LPH 5?? flanking sequence construct from a lactase persistent individual is able to maintain postnatal expression in transgenic mice post weaning.     

Prognostic significance of microalbuminuria in postdiarrheal hemolytic uremic syndrome

Patients who survive the acute phase of postdiarrheal hemolytic uremic syndrome (D+ HUS) may develop renal complications after years of apparent recovery. The optimal regimen for monitoring these children is unclear. We therefore determined if screening for microalbuminuria, in the absence of overt proteinuria at follow-up, increased the sensitivity for predicting long-term renal-related sequelae. We found that screening for microalbuminurea, within the first 6–18 months following an episode of HUS, increased the sensitivity for predicting later sequelae from 22 to 66.7%, compared to screening for overt proteinuria alone. These findings, if confirmed by a larger cohort with more years of follow-up, may facilitate early initiation of intervention strategies designed to reduce progressive renal damage. Dr. Randall M. Lou was a recipient of an International Society of Nephrology Fellowship Training Award. This Research was partially funded by the Lois Joy Galler Foundation for the Hemolytic Uremic Syndrome.     

Erythropoietin inhibits apoptosis induced by photodynamic therapy in ovarian cancer cells

Recombinant human erythropoietin is widely used to treat anemia associated with cancer and with the myelosuppressive effects of chemotherapy, particularly platinum-based regimens. Erythropoietin is the principal regulator of erythroid cell proliferation, differentiation, and apoptosis. Recently, the antiapoptotic and proliferative effects of erythropoietin on nonhematopoietic cells were also established. We now show the effect of erythropoietin treatment on the response of A2780 and SKOV3 ovarian carcinoma cell lines to photodynamic therapy (PDT) using hypericin. SKOV3 exhibited an increased resistance to hypericin when cells were treated with erythropoietin. This resistance was reversed by treatment of SKOV3 cells with the specific Janus kinase 2 kinase inhibitor AG490 or the tyrosine kinase inhibitor genistein. These results support a role for the specific erythropoietin-induced Janus kinase 2/STAT signal transduction pathway in PDT resistance. Evidence of erythropoietin signaling was obtained by the demonstration of Akt phosphorylation in both A2780 and SKOV3 cells. Erythropoietin-treated SKOV3 cells exhibited decreased apoptosis induced by hypericin, an effect that was blocked by the phosphoinositide 3-kinase/Akt inhibitor wortmannin. These results may have important implications for ovarian cancer patients undergoing PDT and receiving erythropoietin.     

Targeted Endodontic Microsurgery: A Novel Approach to Anatomically Challenging Scenarios Using 3-dimensional–printed Guides and Trephine Burs—A Report of 3 Cases

Endodontic microsurgery (EMS) techniques have increased success rates over traditional approaches. Despite surgical advances, anatomically challenging scenarios can preclude EMS in certain cases. The aim of this article was to introduce targeted EMS, which uses 3-dimensional–printed surgical guides (3DSGs) and trephine burs to achieve single-step osteotomy, root-end resection, and biopsy in complex cases. In each of 3 cases, a 3DSG with a trephine port was printed using computer-aided design/computer-aided manufacturing implant planning software. The osteotomy site, angulation, and depth of preparation were defined preoperatively to avoid sensitive anatomic structures. The 3DSG was inserted at the target site to achieve precise osteotomy and root-end resection during surgery. A hollow trephine rotated within the 3DSG port produced single-step osteotomy, root-end resection, and biopsy. Root-end preparation and fill were accomplished, and tissues were sutured in place. Targeted EMS potentiated successful surgical treatment in 3 anatomically challenging scenarios: (1) a palatal approach to the palatal root of a maxillary second molar, (2) a facial approach to a fused distofacial-palatal root of a maxillary first molar, and (3) a mandibular second premolar in close proximity to the mental foramen. Trephine burs guided by 3DSGs produce efficient targeted osteotomies with a predictable site, angulation, and depth of preparation. Apical surgery in challenging anatomic cases such as the palatal root of the maxillary second molar, fused molar roots, and root ends in approximation to the mental nerve are possible with targeted EMS.     

Azathioprine does not reduce adenoma formation in a mouse model of sporadic intestinal tumorigenesis

AIM: To investigate if azathioprine could reduce adenoma formation in ApcMin/+, a mouse model of sporadic intestinal tumorigenesis.METHODS:Azathioprine was administered via drinking water(estimated 6-20 mg/kg body weight per day)to ApcMin/+and wildtype mice.Control animals received vehicle only(DMSO)dissolved in drinking water.At 15wk of age all mice were sacrificed and intestines of ApcMin/+were harvested for evaluation of polyp number.Azathioprine induced toxicity was investigated by immunohistochemical analysis on spleens.RESULTS:All azathioprine treated mice showed signs of drug-associated toxicity such as weight loss and development of splenic T-cell lymphomas.Although this suggests that the thiopurine concentration was clearly in the therapeutic range,it did not reduce tumor formation(48±3.1 adenomas vs 59±5.7 adenomas,P=0.148).CONCLUSION:We conclude that in the absence of inflammation,azathioprine does not affect intestinal tumorigenesis.