Mervat M. El-Deftar

Aberrant expression of cell cycle regulatory genes predicts overall and disease free survival in malignant pleural mesothelioma patients.

BACKGROUND Malignant pleural mesothelioma (MPM) is a highly aggressive disease with a generally poor prognosis. Since escape from cell cycle checkpoint control is common in several solid tumors, the present study was performed to evaluate the role of some cell cycle regulatory genes in the development and progression of MPM. PATIENTS AND METHODS Aberrant expression of p14(ARF), p16(INK4A), p21(waf), p27(KIP), p53, mdm2 and Rb was assessed in 55 MPM cases from Egypt using immunohistochemistry and PCR techniques. Results were correlated with clinico-pathological prognostic factors, overall and disease free survival (OS&DFS). RESULTS Altered expression of p14(ARF), p16(INK4A), p21(waf), p27(KIP1), Rb, p53 and mdm2 proteins was detected in 50.9%, 54.5%, 53.3%, 61.8%, 53.3%, 58.2%, and 50.8% of cases, respectively. SV40 infection significantly correlated with p14(ARF), 16(INK4A), p27(kip1) and Rb aberrations (p=0.014, p=0.02, p=0.01, p=-0.01). Asbestos exposure significantly correlated with p53, p21(waf) and mdm2 aberrations (p=0.001, p=0.03, p=0.02). On multivariate analysis PS ≥ 2, p27(KIP1) and Rb aberrations were independent prognostic factors for OS (p=0.016, p=0.011, p=0.003) whereas on tumor recurrence, p27(KIP1) and Rb aberrations were independent prognostic factors for DFS (p=0.002, p=0.03, p=0.01). CONCLUSIONS MPM is a complex disease characterized by multiple genetic aberrations; some of them involve cell cycle regulatory genes. p14(ARF), p16(INK4A), Rb and p27(KIP1) seem to be involved in SV40-associated MPM whereas mdm2, p53 and p21(WAF) are related to asbestos exposure. In addition to recurrence and PS, only p27(KIP1)and Rb could be used as molecular prognostic markers in MPM.

Properties of modified carboxymethyl cellulose and its use as bioactive compound.

The present study deals with synthesizing novel cellulose derivative, from modifying the carboxymethyl cellulose with amino phenylpropanoic acid (CMC-APP). The synthesized CMC-APP was evaluated as biological and anti-cancer active compound. The molecular structures of this active compound were built using the HyperChem program 7.5, together with conventional analysis (nitrogen content, FT-IR, and non-isothermal TGA analysis). Optimizing the CMC/APPA ratio was carried out as preliminary assessment step, via undetected antimicrobial activity measurement. The TEM study showed that, the synthesized cellulose CMC-APP derivative in the nano-scale particle size (range from 12.5 to 89.3nm). Among all the tested microorganisms and MCF-7 breast cancer cells, the synthesized nano-cellulose derivative is possible used as safety medicine for microbial infections and cancers. The minimal inhibitory concentration (MIC) for Gram-positive bacteria, and gram-negative bacteria are 48.82μg/mL and 97μg/mL, respectively. While, the unicellular fungi and filamentous fungi are 12.2μg/mL and 97.65μg/mL, respectively. The cytotoxic index (IC50) for MCF-7 breast cancers is 50μg/mL. Moreover, the computational study of ADMET (absorption, distribution, metabolism, elimination and toxic) properties, of the molecules showed that, this investigated nano-compound is good oral bioavailability.

Cyclooxygenase-2 expression is associated with elevated aspartate aminotransferase level in hepatocellular carcinoma

BACKGROUND Cyclooxygenase-2 (COX-2), the inducible rate-limiting enzyme of prostaglandins biosynthesis, is involved in the pathogenesis of many chronic inflammation-related human malignancies including hepatocellular carcinoma (HCC). However, its clinical significance in HCC remains obscure. The aim of our study was to evaluate COX-2 expression in HCC and correlate its expression to both clinicopathological parameters and patients survival. MATERIALS AND METHODS The present study was conducted on 17 HCC and 21 adjacent nontumor liver tissues obtained from 22 HCC patients underwent hepatectomy. Eight normal liver tissues taken from normal donors and HepG2 cells were used as controls. Total RNA was extracted and COX-2 mRNA was detected by reverse transcription polymerase chain reaction and correlated to the clinicopathological criteria and to patients survival. RESULTS COX-2 mRNA was detected in 58.8% of the HCC tissues and in 28.6% of the adjacent nontumor liver tissues. COX-2 expression was significantly associated with elevated levels of serum aspartate aminotransferase (AST) with high specificity for disease detection. There was no significance between COX-2 expression and any of the histopathological criteria. CONCLUSIONS COX-2 expression may be involved in HCC carcinogenesis with high specificity for disease detection. COX-2 expression is significantly associated with elevated AST levels indicating a mechanism that may correlate both markers. However COX-2 expression seems to be an independent factor with no correlation to any of the histopathological data or patients survival.

Injectable TEMPO-oxidized nanofibrillated cellulose/biphasic calcium phosphate hydrogel for bone regeneration:

Nanofibrillated cellulose, obtained from rice straw agricultural wastes was used as a substrate for the preparation of a new injectable and mineralized hydrogel for bone regeneration. Tetramethyl pyridine oxyl (TEMPO) oxidized nanofibrillated cellulose, was mineralized through the incorporation of a prepared and characterized biphasic calcium phosphate at a fixed ratio of 50 wt%. The TEMPO-oxidized rice straw nanofibrillated cellulose was characterized using transmission electron microscopy, Fourier transform infrared, and carboxylic content determination. The injectability and viscosity of the prepared hydrogel were evaluated using universal testing machine and rheometer testing, respectively. Cytotoxicity and alkaline phosphatase level tests on osteoblast like-cells for in vitro assessment of the biocompatibility were investigated. Results revealed that the isolated rice straw nanofibrillated cellulose is a nanocomposite of the cellulose nanofibers and silica nanoparticles. Rheological properties of the tested materials are suitable for use as injectable material and of nontoxic effect on osteoblast-like cells, as revealed by the positive alkaline phosphate assay. However, nanofibrillated cellulose/ biphasic calcium phosphate hydrogel showed higher cytotoxicity and lower bioactivity test results when compared to that of nanofibrillated cellulose.

Green carboxymethyl cellulose-silver complex versus cellulose origins in biological activity applications

This article deals with evaluating the role of cellulose origin, from wood and non-wood, on preparing green CMC-Ag complex as biological active agent. Viscose pulp as well as bagasse and rice straw pulps were used in preparation of CMCs, followed by complexation with AgNO3. The complex structure (free-Ag, IR-spectra and TGA), morphology (TEM), antibiological and anti-tumor activities were studied. The data revealed that, the main interaction between CMC and silver is occurred via carboxylate groups and ether link of 1ry alcohol, with formation stable 5-membered ring structure. For the case of RS-based CMC-Ag complex the interaction between COO groups and silica included RS is also possible, via hydrogen bonds. These complexes have anti-biological especially towards gram positive bacteria (B.subtilis, NCID-3610), and uni- and multi cellular fungi. AgNPs from viscose (VCMC-Ag complex) has relatively higher anti-tumor activity for breast cancer MCF-7 in vitro than bagasse-based CMC-Ag complex (BCMC-Ag complex) with IC50 128μg/ml (as Ag). It is interesting to note that; viscose-based CMC-Ag complex (VCMC-Ag) has higher efficient behaviour as bioactive agent than literature reported agents, e.g., Pyridine derivative (∼300μg/ml).

Regeneration of Critical-Size Canine Calvarial Defect by Silica-Calcium Phosphate-Composite (SCPC) and Human Adipose Derived Stem Cells

Reconstruction of large maxillofacial bone defects remains challenging even with diverse current treatment modalities. Silica-calcium phosphate nano composite (SCPC) is a resorbable bioactive bone graft material with a strong stimulatory effect on osteogenic gene expression of osteoblasts and mineralized tissue formation. In a prospective experimental study we investigated the ability of SCPC scaffold seeded with human adipose derived stem cells (ADSCs) to regenerate bone in a critical-size canine calvarial defect. Porous SCPC discs were prepared by powder metallurgy method. ADSCs were isolated from human breast adipose tissue, expanded in vitro and differentiated along osteogenic lineage. Bilateral critical-sized defects, 2.5 cm in diameter each, were made in the calvaria of 12 adult dogs. One calvarial defect was filled by either SCPC disc alone (Group I) or SCPC disc seeded with 2.5 x106 osteoblast-like cells (Group II) while other defect was left empty (ungrafted). Bone tissue regeneration and graft material resorption was evaluated 3 and 6 months postoperative using CT and histology. Calvarial defects grafted with SCPC alone or SCPC-Cell construct were grossly repaired while control ungrafted defect did not repair. Microscopically the newly formed bone in the grafted defects was compact and integrated with the surrounding host tissues. Near complete resorption of the graft material was observed. Histomorphometric analysis demonstrated higher bone surface area and more graft material resorption in defects grafted with SCPC-cell hybrid compared to SCPC alone.

P57Kip2 immunohistochemical staining and flow cytometry ploidy analysis of hydatidiform moles and hydropic abortions

Background The prognosis and the optimum clinical management of hydropic gestation cases rely principally on accurate diagnosis of molar pregnancy subtypes and their distinction from nonmolar hydropic abortus (HA), which is sometimes difficult and uncertain by histopathology. Aim The aim of this article was to perform P57Kip2 immunohistochemical staining and flow cytometry (FCM) ploidy analysis of molar and nonmolar aborted gestations and to assess whether these ancillary techniques combined with histomorphology would refine the diagnosis. Materials and methods The study included 15 complete hydatidiform moles (CHMs), 15 partial hydatidiform moles (PHMs), and 12 HA. Four-micrometer-thick section from each case was immunostained with a monoclonal antibody to P57Kip2 protein, a paternally imprinted cell cycle inhibitor gene. Sections of 50 µm thickness from each case were submitted for analysis of DNA ploidy and S-phase fraction using FCM. Results Initial results showed that all CHM cases were P57Kip2 negative, whereas all HA cases and 13/15 PHMs exhibited positive P57Kip2 expression. Most of the CHM (93.4%) cases were diploid and 6.6% were tetraploid. Eight (53.3%) PHM specimens were diploid and seven (54.7%) were triploid. The majority (75%) of HA were diploid. On histopathological re-evaluation, one of three triploid/P57-positive HA was reclassified as PHM. Three of seven diploid/P57-negative PHMs changed to CHM. Finally, the overall diagnosis was changed in four (∼10%) cases. Conclusion Current study shows that P57-negative expression identifies CHM cases, whereas FCM may aid in distinguishing PHMs from HAs. Hence, ancillary techniques can improve the diagnosis of hydropic gestations in morphologically equivocal cases.

Heteroduplex PCR analysis of rearranged TCRγ genes significantly enhances the detection of clonality in T-cell NHL and T-ALL

Background The detection of clonal T-cell receptor (TCR) &ggr; gene rearrangement by polymerase chain reaction (PCR) is frequently used to aid in the diagnosis of suspect T-cell proliferations. Objectives This work aimed to determine the clonality detection rate in formalin-fixed paraffin-embedded (FFPE) T-cell non-Hodgkin’s lymphomas (NHL) and fresh precursor T-cell acute lymphoblastic leukemia (ALL) cases using PCR amplification of rearranged TCR&ggr; genes before and after heteroduplex (HD) analysis. Methods Two multiplex PCR assays, without and with subsequent HD, were used to amplify portions of rearranged TCR&ggr; genes in histopathologically diagnosed 25 T-cell and 10 B-cell NHLs, 10 reactive lymphoid lesions (FFPE tissues), and 20 T-cell ALL tumors (DNA was extracted from fresh peripheral blood mononuclear cells). Results PCR amplification of TCR&ggr; genes without a subsequent HD step revealed sharp clonal bands in 44% of the FFPE T-cell NHL cases (11/25) and 60% of the T-cell ALL cases (12/20) on a polyacrylamide gel. After HD analysis of PCR products, the rate of clonality detection had improved significantly to 76% in T-cell NHL tumors and to 90% in T-cell ALL tumors (P<0.005). A larger proportion of T-cell NHL (73.6%) and T-cell ALL (66.6%) showed clonal pattern in the first multiplex PCR assay. HD PCR analysis of TCR&ggr; genes was useful in determining the T-cell lineage in the three analyzed anaplastic large-cell lymphomas of the null phenotype. No monoclonal T-cell clones were identified in any of the reactive lymphoid lesions (10 cases), whereas only one B-cell NHL tumor out of 10 tumors analyzed was falsely positive. It was concluded that the multiplex PCR amplification assays for rearranged TCR&ggr; genes, followed by HD analysis significantly enhanced the clonality detection rate in the FFPE T-cell NHL and T-cell ALL cases analyzed.