Effects of THBS3, SPARC and SPP1 expression on biological behavior and survival in patients with osteosarcoma

BACKGROUND: Osteosarcoma is a very aggressive tumor with a propensity to metastasize and invade surrounding tissue. Identification of the molecular determinants of invasion and metastatic potential may guide the development of a rational strategy for devising specific therapies that target the pathways leading to osteosarcoma. METHODS: In this study, we used pathway-focused low density expression cDNA arrays to screen for candidate genes related to tumor progression. Expression patterns of the selected genes were validated by real time PCR on osteosarcoma patient tumor samples and correlated with clinical and pathological data. RESULTS: THBS3, SPARC and SPP1 were identified as genes differentially expressed in osteosarcoma. In particular, THBS3 was expressed at significantly high levels (p = 0.0001) in biopsies from patients with metastasis at diagnosis, which is a predictor of worse overall survival, event-free survival and relapse free survival at diagnosis. After chemotherapy, patients with tumors over-expressing THBS3 have worse relapse free survival. High SPARC expression was found in 51/55 (96.3%) osteosarcoma samples derived from 43 patients, and correlated with the worst event-free survival (p = 0.03) and relapse free survival (p = 0.07). Overexpression of SPP1 was found in 47 of 53 (89%) osteosarcomas correlating with better overall survival, event-free survival and relapse free survival at diagnosis. CONCLUSION: In this study three genes were identified with pattern of differential gene expression associated with a phenotypic role in metastasis and invasion. Interestingly all encode for proteins involved in extracellular remodeling suggesting potential roles in osteosarcoma progression. This is the first report on the THBS3 gene working as a stimulator of tumor progression. Higher levels of THBS3 maintain the capacity of angiogenesis. High levels of SPARC are not required for tumor progression but are necessary for tumor growth and maintenance. SPP1 is not necessary for tumor progression in osteosarcoma and may be associated with inflammatory response and bone remodeling, functioning as a good biomarker

mRNA expression profile of multidrug resistance genes in childhood acute lymphoblastic leukemia : low expression levels associated with a higher risk of toxic death

Increased activity of multidrug resistance (MDR) genes has been associated with treatment failure in acute leukemias, although with controversial reports. The objective of the present study was to assess the expression profile of the genes related to MDR: ABCB1, ABCC1, ABCC3, ABCG2, and LRP/MVP in terms of the clinical and biological variable and the survival of children with acute lymphoblastic leukemia (ALL). The levels of mRNA expression of the drug resistance genes ABCB1, ABCC1, ABCC3, ABCG2, and LRP/MVP were analyzed by quantitative real‐time PCR using the median values as cut‐off points, in consecutive samples from 140 children with ALL at diagnosis. Expression levels of the ABCG2 gene in the patient group as a whole (P = 0.05) and of the ABCG2 and ABCC1 genes in patients classified as being at high risk were associated with higher rates of 5‐year event‐free survival (EFS) (P = 0.04 and P = 0.01). Expression levels of the ABCG2 gene below the median were associated with a greater chance of death related to treatment toxicity for the patient group as a whole (P = 0.009) and expression levels below the median of the ABCG2 and ABCC1 genes were associated with a greater chance of death due to treatment toxicity for the high‐risk group (P = 0.02 and P = 0.03, respectively). The present data suggest a low participation of the drug efflux genes in treatment failure in patients with childhood ALL. However, the low expression of some of these genes may be associated with a higher death risk related to treatment toxicity. Pediatr Blood Cancer 2009;53:996–1004. © 2009 Wiley‐Liss, Inc5369961004FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2001/13206‐9; 2002/03182‐8; 2005/50731‐

Low-Level Laser Therapy in the Prevention and Treatment of Chemotherapy-Induced Oral Mucositis in Young Patients

Abstract Objective: A pilot clinical study was conducted to evaluate the efficacy and feasibility of low-level laser therapy (LLLT) in the prevention and treatment of chemotherapy (CT)-induced oral mucositis (OM) in young patients. Background Data: Besides compromising the patient's nutrition and well-being, oral mucositis represents a portal of entry into the body for microorganisms present in the mouth, which may lead to sepsis if there is hematological involvement. Oncologic treatment tolerance decreases and systemic complications may arise that interfere with the success of cancer treatment. LLLT appears to be an interesting alternative to other approaches to treating OM, due to its trophic, anti-inflammatory, and analgesic properties. Materials and Methods: Patients undergoing chemotherapy (22 cycles) without mucositis were randomized into a group receiving prophylactic laser-irradiation (group 1), and a group receiving placebo light treatment (group 2). Patients who had already presented with mucositis were placed in a group receiving irradiation for therapeutic purposes (group 3, with 10 cycles of CT). Serum granulocyte levels were taken and compared to the progression of mucositis. Results: In group 1, most patients (73%) presented with mucositis of grade 0 (p ϭ 0.03 when compared with the placebo group), and 18% presented with grade 1. In group 2, 27% had no OM and did not require therapy. In group 3, the patients had marked pain relief (as assessed by a visual analogue scale), and a decrease in the severity of OM, even when they had severe granulocytopenia. Conclusion: The ease of use of LLLT, high patient acceptance, and the positive results achieved, make this therapy feasible for the prevention and treatment of OM in young patients. 39