C1QA and COMP: plasma-based biomarkers for early diagnosis of pancreatic neuroendocrine tumors.

Pancreatic Neuroendocrine tumors (PanNET) are challenging to diagnose and often detected at advanced stages due to a lack of specific and sensitive biomarkers. This study utilized proteomics as a valuable approach for cancer biomarker discovery; therefore, mass spectrometry-based proteomic profiling was conducted on plasma samples from 12 subjects (3 controls; 5 Grade I, 4 Grade II PanNET patients) to identify potential proteins capable of effectively distinguishing PanNET from healthy controls. Data are available via ProteomeXchange with the identifier PXD045045. 13.2% of proteins were uniquely identified in PanNET, while 60% were commonly expressed in PanNET and controls. 17 proteins exhibiting significant differential expression between PanNET and controls were identified with downstream analysis. Further, 5 proteins (C1QA, COMP, HSP90B1, ITGA2B, and FN1) were selected by pathway analysis and were validated using Western blot analysis. Significant downregulation of C1QA (p = 0.001: within groups, 0.03: control vs. grade I, 0.0013: grade I vs. grade II) and COMP (p = 0.011: within groups, 0.019: control vs grade I) were observed in PanNET Grade I & II than in controls. Subsequently, ELISA on 38 samples revealed significant downregulation of C1QA and COMP with increasing disease severity. This study shows the potential of C1QA and COMP in the early detection of PanNET, highlighting their role in the search for early-stage (Grade-I and Grade-II) diagnostic markers and therapeutic targets for PanNET.

Hydrogen sulfide promotes migration of trophoblast cells by a Rho GTPase mediated actin cytoskeleton reorganization.

INTRODUCTION: Preeclampsia (PE) arises due to defective spiral artery remodelling which may be due to deficient migration of trophoblast cells. Migration of human endothelial cells has been shown to be promoted via Hydrogen sulphide(H2S)/Rho GTPase Rac1 axis. This novel role of H2S and its downstream processes have not yet been studied in the development and function of the placental trophoblast cells. METHODS: Placental tissues were obtained post-delivery from consented preeclamptic and normotensive mothers (n = 60). The protein expression levels of cystathionine-gamma-lyase (CSE) and cystathionine-beta-synthase (CBS) along with its downstream migratory molecules were compared in both the arms. The pro-migratory role of H2S was investigated in a first trimester placental cell line. RESULTS: H2S promoted the migration of trophoblast cells in a Rho GTPase dependent manner mediated by actin cytoskeleton reorganization. The reduced levels of H2S producing enzymes in the PE placentae along with decreased levels of Rho GTPases (Rac1 and Rho A) corroborate the results of PAG and AOAA treatment in down regulating the Rho GTPases in the in vitro grown placental cultures. Reduction of the migratory potential of trophoblastic cells caused due to hypoxia/reoxygenation was rescued by upregulating the H2S expression with the use of NaHS as a H2S donor. DISCUSSION: Exogenous H2S increases the migratory potential of the placental cells in culture conditions and also post hypoxia/reoxygenation injury. H2S as a gaso-transmitter holds a great potential as a therapeutic agent. Its long-term effects need to be investigated using model systems (rat/mouse) of PE following it up with clinical regulatory trials.

Mechanism of apoptosis activation by Curcumin rescued mutant p53Y220C in human pancreatic cancer.

The mutant p53Y220C (mutp53Y220C) is frequently observed in numerous tumors, including pancreatic cancer. The mutation creates a crevice in the DNA binding core domain and makes p53 a thermally unstable non-functional protein that assists tumor progression and confers resistance to chemotherapeutic drugs. Restoring mutp53 function to its wild type by selectively targeting this crevice with small molecules is a pivotal strategy to promote apoptosis. In this study, we have shown through different biophysical and cell-based studies that curcumin binds and rescues mutp53Y220C to an active wild-type conformation and restores its apoptotic transcription function in BxPC-3-pancreatic cancer cells. In addition, the curcumin-rescued-p53Y220C (CRp53) showed significant hyperphosphorylation at Ser15, Ser20, and acetylation at Lys382 with an 8-fold increase in transcription activity in the BxPC-3 cell lines. We also observed that the active CRp53 escapes Mdm2-mediated proteasomal degradation and the majority of the proteins were localized inside the nucleus with an increased half-life and transcription restoration compared to untreated BxPC-3 cells. By label-free proteomics analysis, we observed that upon curcumin treatment almost 227 proteins were dysregulated with the majority of them being transcriptional targets of p53. Based on our studies, it reflects that apoptosis in pancreatic cancer cells is mediated by curcumin-rescued mutant p53Y220C.

Standardization of the technique of silicon injection of human cadaveric heads for opacification of cerebral vasculature in Indian conditions.

A surgeon's understanding of the surgical anatomy can be greatly enhanced by the dissection of preserved cadaveric specimens. A reliable and inexpensive biological model for testing and standardization of dye injection concentrations is proposed utilizing the goat's head as a biological model. The first phase was concerned with standardization of the dye by titrating its concentration and injecting various amounts into cerebral vessels of a goat's head until an optimal concentration had been ascertained. In the second phase, this optimum concentration of the dye was injected into four human cadaveric heads following the same technique standardized using the goat's head. Upon dissecting the four cadaveric human heads which were injected with silicon dyes and preserved in 10% formalin, the vessels were all well-opacified and the brain was of near normal consistency and good for dissection, without showing any features of putrefaction. The goat model, having similar color, texture, and the handling as the cadaveric head, offers an opportunity to test indigenously manufactured polymerizing dyes in the future. This biological model, therefore, has the potential to considerably reduce the cost of cadaver preparation.

Role of oxidative stress markers and antioxidants in the placenta of preeclamptic patients.

AIM: The present study aimed to evaluate and compare the placental variables of oxidative stress markers in preeclamptic women. METHODS: A total of 60 placentas were collected. Of these, 30 were obtained from normotensive pregnancies, and 30 from pregnancies with preeclampsia as per International Society for the Study of Hypertension in Pregnancy (ISSHP) criteria. Each placental tissue was analyzed for levels of pro-oxidant (malondialdehyde) and antioxidants (glutathione and superoxide dismutase) using the standard enzymatic assays. RESULTS: Malondialdehyde levels were significantly higher (12.21 ± 4.1 versus 4.7 ± 2.1 nmol/g tissue, P < 0.0001) and glutathione (GSH) levels were significantly lower (0.46 ± 0.37 versus 1.03 ± 0.43 µmol/g tissue, P < 0.0001) in the placentas of preeclamptic women when compared to those of normal pregnancies. Though not statistically significant, decreases in superoxide dismutase levels were observed in placentas of preeclamptic women (4.14 ± 2.25 versus 5.22 ± 2.0 units/mg tissue protein, P < 0.055). Receiver operator characteristic curve analysis of malondialdehyde revealed a sensitivity of 87% and specificity of 87%, at a cutoff value 6.5 nmol/g. Similarly, GSH had a sensitivity of 77% and a specificity of 77% at a cutoff value 0.62 µmol/g. CONCLUSION: The present study demonstrated that increased placental lipid peroxidation and decreased levels of antioxidants may play an important role in the pathogenesis of preeclampsia. These findings are suggestive of involvement of oxidative stress markers in preeclamptic patients.

Circulating angiogenic factors in pregnancies complicated by pre-eclampsia.

BACKGROUND: Pre-eclampsia is an inflammatory disorder characterized by diffuse endothelial dysfunction possibly secondary to impaired trophoblast invasion of the spiral arteries during implantation. It is associated with alterations in maternal serum concentrations of vascular endothelial growth factor (VEGF), placental growth factor (PIGF) and soluble fms-like tyrosine kinase-1 (sFlt-1). We did a case-control study to ascertain whether pre-eclampsia is associated with changes in serum concentrations of VEGF, PIGF and sFlt-1 in Indian patients. METHODS: Serum samples were obtained from 40 women with pre-eclampsia and 40 normotensive, non-proteinuric pregnant women. The levels of VEGF, PIGF and sFlt-1 were analysed using ELISA. RESULTS: In the sera of pregnant women with pre-eclampsia, the levels of sFlt-1 were significantly higher than those in the sera of normotensive, non-proteinuric pregnantwomen (median 11295.25 v. 2936.2 pg/ml, p < 0.0001), whereas there was a significant reduction in the levels of free VEGF (mean [SD] 170.53 [36.56] pg/ml v. 254.61 [47.39] pg/ml, p < 0.0001) and PIGF (mean [SD] 236.77 [93.70] pg/ml v. 744.98 [168.55] pg/ml, p < 0.0001). CONCLUSION: An increase in sFlt-1 levels and a simultaneous decrease in free VEGF and PIGF levels in the sera of women with pre-eclampsia as compared with normotensive, nonproteinuric pregnant women suggest that an imbalance between the levels of these pro- and anti-angiogenic factors'may have a role to play in the pathogenesis of pre-eclampsia.