Osteonecrosis of the jaw in a Crohn’s disease patient following a course of Bisphosphonate and Adalimumab therapy: a case report

Background

Cyclooxygenase-2 (COX-2, PTGS2) is an enzyme involved in the synthesis of prostaglandins and thromboxanes, which are regulators of biologic processes such as inflammation, cell proliferation and angiogenesis. COX-2 over-expression was reported in many (pre) malignant tissues, but data strongly vary and seem to depend on the methodology used.

Methods

Normal colorectal mucosa and paired cancerous tissue from 60 patients with colorectal cancer was investigated for the levels of COX-2 mRNA by real-time quantitative Polymerase Chain Reaction (qPCR). COX-2 levels were expressed relative to either: tissue weight or levels of the housekeeping genes beta-2 microglobulin (B2M) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH).

Results

COX-2 mRNA levels, normalized with respect to tissue weight or mRNA levels of the housekeeping genes B2M or GAPDH, were over-expressed in 80%, 70% and 40% of the colorectal tumor tissues, as compared to the paired adjacent normal colorectal mucosa samples, respectively. Highest mRNA COX-2 ratios tumor/normal were measured when expressed per mg tissue (mean ratio 21.6). When normalized with respect to the housekeeping genes B2M or GAPDH, mean tumor/normal ratios were 16.1 and 7.5, respectively.

Conclusion

Expression of COX-2 mRNA levels per mg tissue is most simple in comparison to normalization with respect to the housekeeping genes B2M or GAPDH. Levels of COX-2 mRNA are found over-expressed in almost 80% of the colorectal tumors, compared to paired adjacent normal colorectal mucosa, suggesting a role of COX-2 as a potential biomarker for cancer risk, whereas inhibitors of COX-2 could be of value in chemoprevention of colon cancer.     

Discovery and antiproliferative evaluation of new quinoxalines as potential DNA intercalators and topoisomerase II inhibitors

In continuation of our previous work on the design and synthesis of topoisomerase II (Topo II) inhibitors and DNA intercalators, a new series of quinoxaline derivatives were designed and synthesized. The synthesized compounds were evaluated for their cytotoxic activities against a panel of three cancer cell lines (Hep G‐2, Hep‐2, and Caco‐2). Compounds 18b, 19b, 23, 25b , and 26 showed strong potencies against all tested cell lines with IC₅₀ values ranging from 0.26 ± 0.1 to 2.91 ± 0.1 µM, comparable with those of doxorubicin (IC₅₀ values ranging from 0.65 ± 0.1 to 0.81 ± 0.1 µM). The most active compounds were further evaluated for their Topo II inhibitory activities and DNA intercalating affinities. Compounds 19b and 19c exhibited high activities against Topo II (IC₅₀ = 0.97 ± 0.1 and 1.10 ± 0.1 µM, respectively) and bound the DNA at concentrations of 43.51 ± 2.0 and 49.11 ± 1.8 µM, respectively, whereas compound 28b exhibited a significant affinity to bind the DNA with an IC₅₀ value of 37.06 ± 1.8 µM. Moreover, apoptosis and cell‐cycle tests of the most promising compound 19b were carried out. It was found that 19b can significantly induce apoptosis in Hep G‐2 cells. It has revealed cell‐cycle arrest at the G2/M phase. Moreover, compound 19b downregulated the Bcl‐2 levels, indicating its potential to enhance apoptosis. Furthermore, molecular docking studies were carried out against the DNA–Topo II complex to examine the binding patterns of the synthesized compounds.     

Iron overload in non-transfusion-dependent thalassemia: a clinical perspective

Iron overload due to increased intestinal iron absorption represents an important clinical problem in patients with non-transfusion-dependent thalassemia (NTDT), particularly as they advance in age. Current models for iron metabolism in patients with beta (β)-thalassemia intermedia (TI) suggest that suppression of serum hepcidin results in increased iron absorption and release of iron from the reticuloendothelial system, leading to depletion of macrophage iron, relatively low levels of serum ferritin, and liver iron loading. The clinical consequences of iron overload in patients with NTDT are multifactorial and include endocrinopathy, bone disease, thromboembolism, pulmonary hypertension, cerebrovascular and neuronal damage, liver fibrosis or cirrhosis, and increased risk of hepatocellular carcinoma. Although serum ferritin levels correlate with liver iron concentration (LIC), they underestimate iron load in these patients compared with transfusion-dependent patients with equivalent LIC. Therefore, direct measurement of LIC is recommended with chelation therapy as indicated.     

Contemporary approaches to treatment of beta-thalassemia intermedia

Beta-thalassemia intermedia (TI) is associated with a variety of serious clinical complications that require proactive and comprehensive management. These include skeletal deformities and osteopenia, compensatory extramedullary hematopoiesis and tumor formation, progressive splenomegaly, a hypercoagulable state resulting in thromboembolic events and pulmonary hypertension, and increased gastrointestinal iron absorption that often results in nontransfusional iron overload and liver damage. Although TI is generally considered a non-transfusion-dependent thalassemia, transfusion therapy may be an important part of the comprehensive management of this disease. This review describes the current state of the art for medical management of TI, with particular focus on the roles of splenectomy, transfusion, and iron chelation therapy.     

Protective effect of curcumin on N-nitrosodiethylamine and carbon tetrachloride-induced hepatocarcinogenesis in Sprague–Dawley rats

Curcumin, the yellow spice derived from the roots (rhizomes) of the plant Curcuma longa, has been reported to have a chemoprotective effect against several neoplasms. The protective effect of curcumin during N-nitrosodiethylamine- and carbon tetrachloride-induced hepatocarcinogenesis in Sprague–Dawley rats and its effect on the expression of IkappaB-alpha mRNA were evaluated. Sixty male rats were randomly assigned into four experimental groups. Group A animals received a single i.p. injection of N-nitrosodiethylamine (200 mg/kg b.w.). After 1 week, the animals received weekly s.c. injections of carbon tetrachloride (3 ml/kg b.w./week) for 6 weeks. Group B was given diet containing 0.2 % curcumin 2 weeks before the injection of N-nitrosodiethylamine and continued throughout the experimental period (20 weeks). Group C was given only a diet containing 0.2 % curcumin for the whole period of the experiment. Group D animals served as control. The level of IkappaB-alpha (IкB-α) mRNA was determined by semiquantitative PCR. Administration of diet containing 0.2 % curcumin, 2 weeks before the injection of N-nitrosodiethylamine and throughout the period of experiment, decreased percentage of preneoplastic foci in hepatic parenchyma and inhibited the development of hepatocellular carcinoma, cholangiofibrosis, and cystic cholangioma in rat liver. Moreover, curcumin administration decreased the number and size of the preneoplastic foci induced by N-nitrosodiethylamine and carbon tetrachloride in the liver. The densitometric analysis of the IкB-α mRNA bands revealed that curcumin administration blocked the decrease of IкB-α mRNA induced by N-nitrosodiethylamine and carbon tetrachloride. These results concluded that curcumin inhibited hepatocarcinogenesis induced by N-nitrosodiethylamine and carbon tetrachloride through blocking IкB-α degradation.