Apoptosis in cancer: from pathogenesis to treatment

Background

Hypoxia-inducible factor-1 alpha (HIF-1α) maybe an important regulatory factor for angiogenesis of small cell lung cancer (SCLC). Our study aimed to investigate the effect of HIF-1α on angiogenic potential of SCLC including two points: One is the effect of HIF-1α on the angiogenesis of SCLC in vivo. The other is the regulation of angiogenic genes by HIF-1α in vitro and in vivo.

Methods

In vivo we used an alternative method to study the effect of HIF-1a on angiogenic potential of SCLC by buliding NCI-H446 cell transplantation tumor on the chick embryo chorioallantoic membrane (CAM) surface. In vitro we used microarray to screen out the angiogenic genes regulated by HIF-1a and tested their expression level in CAM transplantation tumor by RT-PCR and Western-blot analysis.

Results

In vivo angiogenic response surrounding the SCLC transplantation tumors in chick embryo chorioallantoic membrane (CAM) was promoted after exogenous HIF-1α transduction (p < 0.05). In vitro the changes of angiogenic genes expression induced by HIF-1α in NCI-H446 cells were analyzed by cDNA microarray experiments. HIF-1α upregulated the expression of angiogenic genes VEGF-A, TNFAIP6, PDGFC, FN1, MMP28, MMP14 to 6.76-, 6.69-, 2.26-, 2.31-, 4.39-, 2.97- fold respectively and glycolytic genes GLUT1, GLUT2 to2.98-, 3.74- fold respectively. In addition, the expression of these angiogenic factors were also upregulated by HIF-1α in the transplantion tumors in CAM as RT-PCR and Western-blot analysis indicated.

Conclusions

These results indicated that HIF-1α may enhance the angiogenic potential of SCLC by regulating some angiogenic genes such as VEGF-A, MMP28 etc. Therefore, HIF-1α may be a potential target for the gene targeted therapy of SCLC.     

Clinicopathologic characteristics and therapeutic outcomes of primary gastrointestinal non-Hodgkin's lymphomas in central Anatolia, in Turkey

Primary gastrointestinal lymphoma is a common presentation of non-Hodgkin's lymphoma. The main controversy arises when many aspects of its classification and management are under discussion, particularly regarding roles for surgical resection. The aim of this study was to evaluate clinicopathologic characteristics and the therapeutic outcome of primary gastrointestinal non-Hodgkin's lymphoma. We carried out a retrospective analysis of 74 patients who were presented to our center with histopathological diagnosis of primary gastro-intestinal non-Hodgkin's lymphoma between 1990 and 2001. All patients have been staged according to Lugano Staging System. For histopathological classification, International Working Formulation was applied. The treatment choice concerning the surgical or non-surgical management was decided by the initially acting physician. Treatment modalities were compared using the parameters of age, sex, histopathological results, stage, and the site of disease. Of the 74 patients, 31 were female and 43 were male, with a median age of 49 years (range 15-80). The stomach was the most common primary site and was seen in 51 of 74 patients (68.9%). The intermediate and high grade lymphomas constituted 91.9% of the all cases. In a median follow-up of 29 months (range 2-128), 20 out of 74 patients died. There was a three year overall survival rate in 65.4% of all patients. The three year overall survival rate was better in stage I and II1 patients who were treated with surgery plus chemotherapy (+/-RT) than those treated with chemotherapy alone (93.7% vs. 55.6%, p < 0.05). The stage and presence of B symptoms affected the disease free survival and overall survival significantly, but the histopathologic grade only affected the overall survival. On the basis of these results, we suggest that surgical resection is necessary before chemotherapy in early stage (stage I and II1) patients with gastrointestinal non-Hodgkin's lymphomas because of the significant survival advantage it would bring to the patient.     

Osteogenic induction of human periodontal ligament fibroblasts under two- and three-dimensional culture conditions

Human periodontal ligament fibroblasts (hPDLF) play a key role in the regeneration of periodontal compartment during guided tissue regeneration procedures. This property is attributed to the progenitor cell subsets residing in the area. The aim of this study was to investigate whether hPDLFs could undergo an osteogenic differentiation under two- and three-dimensional (2D and 3D) culture conditions upon osteogenic induction. hPDLFs were isolated from six healthy donors, cultured, and expanded according to standard protocols. Then, three osteogenic culture conditions (dexamethasone, ascorbic acid, and beta-glycerophosphate) were established: 1) 2D culture as single-cell monolayer, 2) 3D-static culture on mineralized poly(DL-lactic-co-glycolic acid) (PLGA) scaffold, and 3) 3D culture on mineralized PLGA scaffold inside the NASA-approved bioreactor stimulating microgravity conditions. After 21 days of osteogenic induction, the majority of monolayer cultures had undergone differentiation toward osteogenic lineage, as indicated by morphological changes, mineralization assay, and some phenotypical properties. However, immunohistochemistry revealed that the scaffold cultures expressed higher levels of osteogenic marker proteins compared with that of the monolayers. Secondly, hPDLF-PLGA constructs in bioreactor showed an increased expression of osteopontin and osteocalcin compared with that of static 3D culture after 21 days. Results indicate that human periodontal ligament contains a subpopulation of cells capable of undergoing osteogenic differentiation and presumably contributing to regeneration of bone defects in the adjacent area. Human PDLF-seeded mineralized PLGA scaffold in microgravity bioreactor may be used to support osteogenic differentiation in vitro. Thus, this system may offer new potential benefits as a tool for periodontal tissue engineering.     

Intracerebral hematoma complicated with brain abscess in an infant. Case report

A 45-day-old infant presented with a rare case of intracerebral hematoma complicated with brain abscess which developed after vitamin K deficiency. He was admitted to our emergency department with complaints of fever and confusion. Physical, neurological, and laboratory examinations and cranial computed tomography identified vitamin K deficiency and intracerebral hematoma. He started to suffer convulsions. The patient underwent surgery. A brain abscess was discovered with an intracerebral hematoma. The intracerebral hematoma and abscess were evacuated and antibiotic therapy was initiated. Convulsions became rare and were controlled with midozalam administration. Follow-up computed tomography after 6 months showed encephalomalacic changes in the temporoparietal area. If feeding depends only on human milk, the amount of vitamin K prophylaxis given to neonates should be increased to support vitamin K related factors.