SIRT1/FOXO Signaling Pathway in Breast Cancer Progression and Metastasis.

Breast cancer is the second most common cancer in women. The roles of the SIRT and FoxO proteins in tumor progression are known, but their roles in metastasis have not yet been clearly elucidated. In our study, we investigated the roles of SIRT and FoxO proteins their downstream pathways, proteins p21 and p53, in tumor progression and metastasis. We evaluated these proteins in vitro using metastatic 4TLM and 67NR cell lines, as well as their expression levels in tumor-bearing mice. In addition, the regulatory role of SIRT and FoxO proteins in different transduction cascades was examined by IPA core analysis, and clinicopathological evidence was investigated in the TCGA database. In primary tumors, the expression levels of SIRT1, p21, p53, E2F1 and FoxO proteins were higher in 67NR groups. In metastatic tissues, the expression levels of SIRT1, E2F1 and FoxO proteins were found to be enhanced, whereas the levels of p53 and p21 expression were noted to be reduced. IPA analysis also provided empirical evidence of the mechanistic involvement of SIRT and FoxO proteins in tumor progression and metastasis. In conclusion, SIRT1 was found to co-operate with FoxO proteins and to play a critical role in metastasis. Additional research is required to determine why overexpression of SIRT1 in metastatic tissues has oncogenic effects.

Correlation of miRNAs With Prognosis in Composite Tissue Allotransplantation.

OBJECTIVES: The number of composite tissue allotransplant procedures is increasing and has gained popularity. As with other transplant procedures, early detection of possible pathologies is as important as clinical follow-up. The present study investigated the correlation between microRNA expression levels and clinical follow-up of individuals undergoing composite tissue transplant. MATERIALS AND METHODS: Whole microRNA expression levels were analyzed from peripheral blood mononuclear cells obtained from preoperative and postoperative blood of patients who underwent facial transplant. Analyses were performed using microRNA levels from patients' preoperative blood samples. RESULTS: The clinical findings of patients with facial transplant were correlated with individual miRNA expression level changes. The expression of miR-31, the high expression of which has been linked to rejection, was significantly low in our patients. No expression changes were observed in other rejection-related microRNAs. Grade 1 rejection was generally seen in our patients, and these findings are consistent with the degree and frequency of rejection episodes in our cases. In addition, immunosuppression-associated diseases such as squamous cell carcinoma, posttransplant lymphoproliferative disorders, and aspergillosis, which are encountered clinically, were found to correlate with expression changes in microRNAs such as miR-150-5p, miR-21-5p, miR-17-5p, miR-20a-5p, and miR-3607-5p. CONCLUSIONS: Defining the clinical findings and immunosuppression-associated pathologies encountered in composite tissue transplant using biomarkers such as microRNA can play an important role in the improvement of these transplant procedures and in predicting patient morbidity. Therefore, the use of microRNAs may be useful in the clinical follow-up of patients who have received composite tissue allotransplant.

Clinical significance of TRAIL and TRAIL receptors in patients with head and neck cancer.

BACKGROUND: Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a death ligand currently under clinical trials for cancer. The molecular profile of TRAIL and TRAIL receptors has not yet been mapped for patients with laryngeal squamous cell carcinoma (SCC) or patients with oral cavity squamous cell carcinoma (OCSCC). METHODS: Paraffin-embedded tissues from 60 patients with laryngeal SCC and 14 patients with OCSCC were retrospectively analyzed using immunohistochemistry. RESULTS: An increase in decoy-R1 (DcR1) but a decrease in decoy-R2 (DcR2) expression were observed in patients with laryngeal SCC and in patients with OCSCC compared with control individuals with benign lesions. Clinical and pathologic grading revealed distinctive TRAIL and TRAIL receptor profiles in patients with squamous cell carcinoma of the head and neck (SCCHN). CONCLUSIONS: TRAIL and a TRAIL receptor expression profile might be useful to follow-up disease progression by virtue of its connection with clinical staging and pathologic grading in patients with laryngeal SCC.

NF-κB targeting by way of IKK inhibition sensitizes lung cancer cells to adenovirus delivery of TRAIL.

BACKGROUND: Lung cancer causes the highest rate of cancer-related deaths both in men and women. As many current treatment modalities are inadequate in increasing patient survival, new therapeutic strategies are required. TNF-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in tumor cells but not in normal cells, prompting its current evaluation in a number of clinical trials. The successful therapeutic employment of TRAIL is restricted by the fact that many tumor cells are resistant to TRAIL. The goal of the present study was to test a novel combinatorial gene therapy modality involving adenoviral delivery of TRAIL (Ad5hTRAIL) and IKK inhibition (AdIKKßKA) to overcome TRAIL resistance in lung cancer cells. METHODS: Fluorescent microscopy and flow cytometry were used to detect optimum doses of adenovirus vectors to transduce lung cancer cells. Cell viability was assessed via a live/dead cell viability assay. Luciferase assays were employed to monitor cellular NF-κB activity. Apoptosis was confirmed using Annexin V binding. RESULTS: Neither Ad5hTRAIL nor AdIKKßKA infection alone induced apoptosis in A549 lung cancer cells, but the combined use of Ad5hTRAIL and AdIKKßKA significantly increased the amount of A549 apoptosis. Luciferase assays demonstrated that both endogenous and TRAIL-induced NF-κB activity was down-regulated by AdIKKßKA expression. CONCLUSIONS: Combination treatment with Ad5hTRAIL and AdIKKßKA induced significant apoptosis of TRAIL-resistant A549 cells, suggesting that dual gene therapy strategy involving exogenous TRAIL gene expression with concurrent IKK inhibition may be a promising novel gene therapy modality to treat lung cancer.

TRAIL death receptor-4, decoy receptor-1 and decoy receptor-2 expression on CD8+ T cells correlate with the disease severity in patients with rheumatoid arthritis.

BACKGROUND: Rheumatoid Arthritis (RA) is a chronic autoimmune inflammatory disorder. Although the pathogenesis of disease is unclear, it is well known that T cells play a major role in both development and perpetuation of RA through activating macrophages and B cells. Since the lack of TNF-Related Apoptosis Inducing Ligand (TRAIL) expression resulted in defective thymocyte apoptosis leading to an autoimmune disease, we explored evidence for alterations in TRAIL/TRAIL receptor expression on peripheral T lymphocytes in the molecular mechanism of RA development. METHODS: The expression of TRAIL/TRAIL receptors on T cells in 20 RA patients and 12 control individuals were analyzed using flow cytometry. The correlation of TRAIL and its receptor expression profile was compared with clinical RA parameters (RA activity scored as per DAS28) using Spearman Rho Analysis. RESULTS: While no change was detected in the ratio of CD4+ to CD8+ T cells between controls and RA patient groups, upregulation of TRAIL and its receptors (both death and decoy) was detected on both CD4+ and CD8+ T cells in RA patients compared to control individuals. Death Receptor-4 (DR4) and the decoy receptors DcR1 and DcR2 on CD8+ T cells, but not on CD4+ T cells, were positively correlated with patients' DAS scores. CONCLUSIONS: Our data suggest that TRAIL/TRAIL receptor expression profiles on T cells might be important in revelation of RA pathogenesis.

In vivo fluorescence imaging is well-suited for the monitoring of adenovirus directed transgene expression in living organisms.

PURPOSE: We tested a new light detection cooled charge-coupled device (CCD) for in vivo assessment of noninvasive, whole-body fluorescence optical imaging of adenovirus directed enhanced green fluorescent protein (AdEGFP) expression. PROCEDURES: AdEGFP was injected i.v. into BALB/c mice via tail vein. Whole-body fluorescence optical imaging of AdEGFP expression was performed using a Kodak 2000MM Image Station before and after vector administration. RESULTS: EGFP expression was exclusively detected around the abdominal cavity, and the fluorescent signal peaked at day 4 and then remained detectable for at least 30 days. Ex vivo fluorescence imaging confirmed that EGFP expression was restricted to the liver, and transgene expression was homogeneously diffused into all four lobes. CONCLUSIONS: These findings demonstrate that in vivo fluorescence imaging provides functional data indicating the approximate location, magnitude, and duration of AdEGFP expression.

Detection of micrometastatic tumor cells in head and neck squamous cell carcinoma. A possible predictor of recurrences?

OBJECTIVE: To evaluate the presence of micrometastatic tumor cells in the peripheral blood samples of the patients with head and neck squamous cell carcinoma (HNSCC) and to determine whether the presence of micrometastatic cells had any biological relevance in terms of local recurrences or metastasis during a follow-up period of 3 years. METHODS: We included 21 consecutive patients with untreated primary HNSCC admitted to the Ear Nose and Throat Department of Akdeniz University Medical School, Antalya, Turkey between February and October 2002. Squamous carcinoma cells in peripheral blood samples of these patients prior to surgery were detected via a magnetic cell separation technique using anti-epithelial cell adhesion molecule antibody, and thereafter evaluated by light microscopy with hematoxylin and eosin staining. RESULTS: Seven out of 21 patients showed squamous carcinoma cells in peripheral blood samples. Patients with stage III and IV tumors were nearly 5 times more likely to show micrometastatic cells compared with those with stage I and II tumors (6/12 versus 1/9). During the follow-up, 2 patients out of 7 with micrometastasis had recurrences. None in the micrometastasis negative group relapsed. CONCLUSION: We suggest that HNSCC patients with detectable tumor cells in peripheral blood represent a subset of patients who should be followed up more closely for possible recurrences.

Apoptosis of cord blood neutrophils and their response to colony-stimulating factors.

Neutrophil production and functions are immature in newborns. Although neutrophil kinetics during neonatal period have been widely studied, little is known about the effect of apoptosis on these defects. In this study, we examine the apoptosis of neonatal neutrophils and the effects of colony-stimulating factors (CSF) on this process. The study was performed using three different methodologies (morphological analysis, surface Fas expression, and mitochondrial 7A6 antigen expression) and the results were compared with adult controls. Neonatal neutrophils more rapidly underwent apoptosis in comparison to adult neutrophils. The above-mentioned three different methods gave similar results. Granulocyte-CSF (G-CSF) and granulocyte-macrophage CSF (GM-CSF) decreased the apoptosis of neutrophils in newborns and adults. This effect was significantly more pronounced in adults than newborns in morphological analysis. Increased apoptosis may contribute to qualitative and quantitative defects of neutrophils during neonatal period and may be an explanation for the proneness of newborn to develop neutropenia during systemic infections.