Maria Teresa de Seixas Alves

Results of the brazilian osteosarcoma treatment group studies III and IV : Prognostic factors and impact on survival

PURPOSE To evaluate the impact of chemotherapy and surgery on the outcome of osteosarcoma (OS) of the extremities and to identify prognostic factors in Brazilian patients. PATIENTS AND METHODS A total of 225 patients with metastatic and nonmetastatic OS of the extremities were enrolled and assessed in two consecutive studies designed and implemented by the Brazilian Osteosarcoma Treatment Group. RESULTS The 5-year survival and event-free survival rates for the 209 assessable patients were 50.1% and 39%, respectively; for the 178 patients with nonmetastatic disease at diagnosis, the rates were 60.5% and 45.5%, respectively. The multivariate analysis showed that the following variables were associated with a shorter survival: metastases at diagnosis (P < .001), necrosis grades 1 and 2 (P = .046), and tumor size (P = .0071). CONCLUSION The overall 5- and 10-year survival rates were lower than the rates reported in North American and European trials. A pattern of advanced disease at diagnosis was often present, with a high proportion of patients having metastases (20.8%) and large tumor size (42.9%). However, these features were not necessarily associated with longer duration of prediagnostic symptoms. These findings were considered in the strategic planning of the current Brazilian cooperative study, with the aim of improving survival and quality of life of a large number of patients with OS.

Prognostic factors and outcomes for osteosarcoma: an international collaboration

We aimed to evaluate the prognostic significance of traditional clinical predictors in osteosarcoma through an international collaboration of 10 teams of investigators (2680 patients) who participated. In multivariate models the mortality risk increased with older age, presence of metastatic disease at diagnosis, development of local recurrence when the patient was first seen, use of amputation instead of limb salvage/wide resection, employment of unusual treatments, use of chemotherapeutic regimens other than anthracycline and platinum and use of methotrexate. It was also influenced by the site of the tumour. The risk of metastasis increased when metastatic disease was present at the time the patient was first seen and also increased with use of amputation or unusual treatment combinations or chemotherapy regimens not including anthracycline and platinum. Local recurrence risk was higher in older patients, in those who had local recurrence when first seen and when no anthracycline and platinum were used in chemotherapy. Results were similar when limited to patients seen after 1990 and treated with surgery plus combination chemotherapy. This large-scale international collaboration identifies strong predictors of major clinical outcomes in osteosarcoma.

Histologic Analysis of Zafirlukast’s Effect on Capsule Formation Around Silicone Implants

BackgroundThe most common complication experienced by patients who have undergone mammary implant surgery is capsular contracture. This matter concerns physicians and patients, but to date, there is no effective way to avoid this complication. Surgical intervention usually is required. In 2002, the use of zafirlukast, a leukotriene inhibitor (a drug used for asthma treatment), was reported for the treatment of capsular contracture, with good results.MethodsFor this study, 30 female Wistar rats were used. These animals received two silicone implants each: one with a smooth surface and one with a textured surface. All the animals received daily intraperitoneal injections for 90 days and were divided as follows: control group (C) receiving only saline solution, experimental group 1 (E-I) receiving 1.25 mg/kg/day of zafirlukast, and experimental group 2 (E-II) receiving 5 mg/kg/day of zafirlukast. Histologic analysis used hematoxilin and eosin to verify vessels, capsule thickness, and inflammatory cells. Immunoistochemical analysis with smooth muscle anti-actin antibody was used for myofibroblast verification. Picro-Sirius under polarized light was used for collagen analysis.ResultsTextured implant experimental groups presented smaller numbers of vessels, thinner capsules, lower collagen density, and smaller numbers of mastocytes and eosinophils than the control group. No significant differences were found in smooth surface implants, as compared with the control group.ConclusionZafirlukast reduced the occurrence of factors directly and indirectly connected with capsular contracture.

EFFECTS OF LOW-LEVEL LASER THERAPY ON COLLAGEN EXPRESSION AND NEUTROPHIL INFILTRATE IN 5-FLUOROURACIL-INDUCED ORAL MUCOSITIS IN HAMSTERS

Several studies have suggested that low‐level laser therapy (LLLT) can ameliorate oral mucositis; however, the mechanisms involved are not well understood. The aim of this study was to investigate the mechanisms of action of LLLT on chemotherapy‐induced oral mucositis, as related to effects on collagen expression and inflammation.

Cystic phaeochromocytoma is a distinctive subgroup with special clinical, imaging and histological features that might mislead the diagnosis.

To report and analyse cases of cyctic phaeochromocytoma at our institution and in previous publications, as adrenal cystic masses are usually associated with nonfunctional lesions, but they can be phaeochromocytoma.

Urine is Necessary to Provoke Bladder Inflammation in Protamine Sulfate Induced Urothelial Injury

PURPOSE The bladder is normally impermeable to possible hostile environmental factors and toxic urinary wastes. Any disruption of the permeability barrier would permit the leakage of urine constituents into the underlying cells layers and subsequent inflammation. Protamine sulfate, which increases urothelial permeability, is used in experimental models of cystitis. We examined whether protamine sulfate alone could cause bladder inflammation or if the association of protamine sulfate and urine is needed for this condition. MATERIALS AND METHODS Female Wistar rats (Center for the Development of Experimental Models for Medicine and Biology, Federal University of São Paulo, São Paulo, Brazil) had the bladder catheterized and instilled with protamine sulfate (10 mg) or sterile saline for 30 minutes. To exclude urine other groups of rats underwent bilateral nephrectomy and the same procedure was used. One day after instillation the bladders were removed for histopathology. Edema and vascular congestion were graded from 0-none to 3-severe. Polymorphonuclear and mast cells were counted. The Kruskal-Wallis test was performed for statistical analysis. RESULTS Intravesical instillation of protamine sulfate in nonnephrectomized rats led to inflammation, in contrast to findings in rats instilled with saline. On the other hand, nephrectomized rats showed no inflammatory changes following the instillation of protamine sulfate or saline. The mast cell count was similar in all groups. CONCLUSIONS Bladder inflammation in this experimental model of urothelial injury was not due to protamine sulfate alone. The association of protamine sulfate and urine was necessary to trigger the inflammatory cascade. Thus, urine indeed has an important role in the development of bladder inflammation in an environment of higher urothelial permeability.

Urinary glycosaminoglycans excretion and the effect of dimethyl sulfoxide in an experimental model of non-bacterial cystitis

PURPOSE We reproduced a non-bacterial experimental model to assess bladder inflammation and urinary glycosaminoglycans (GAG) excretion and examined the effect of dimethyl sulfoxide (DMSO). MATERIALS AND METHODS Female rats were instilled with either protamine sulfate (PS groups) or sterile saline (control groups). At different days after the procedure, 24 h urine and bladder samples were obtained. Urinary levels of hyaluronic acid (HA) and sulfated glycosaminoglycans (S-GAG) were determined. Also to evaluate the effect of DMSO animals were instilled with either 50% DMSO or saline 6 hours after PS instillation. To evaluate the effect of DMSO in healthy bladders, rats were instilled with 50% DMSO and controls with saline. RESULTS In the PS groups, bladder inflammation was observed, with polymorphonuclear cells during the first days and lymphomononuclear in the last days. HA and S-GAG had 2 peaks of urinary excretion, at the 1st and 7th day after PS injection. DMSO significantly reduced bladder inflammation. In contrast, in healthy bladders, DMSO produced mild inflammation and an increase in urinary HA levels after 1 and 7 days and an increase of S-GAG level in 7 days. Animals instilled with PS and treated with DMSO had significantly reduced levels of urinary HA only at the 1st day. Urinary S-GAG/Cr levels were similar in all groups. CONCLUSIONS Increased urinary levels of GAG were associated with bladder inflammation in a PS-induced cystitis model. DMSO significantly reduced the inflammatory process after urothelial injury. Conversely, this drug provoked mild inflammation in normal mucosa. DMSO treatment was shown to influence urinary HA excretion.

Urinary Glycosaminoglycans as Biomarker for Urothelial Injury: Is It Possible to Discriminate Damage From Recovery?

OBJECTIVES The glycosaminoglycan (GAG) layer is referred to as a bladder protective factor. We reproduced an experimental model of urothelial damage to assess GAG metabolism in the process of injury and recovery of the urothelium. METHODS Wistar female rats were bladder catheterized and instilled with either protamine sulfate (PS groups) or sterile saline (control groups). At different days after the procedure, 24-hour urine samples were obtained. The urinary levels of hyaluronic acid (HA) and sulfated glycosaminoglycan were determined in all groups and in nonmanipulated rats (day 0). Additionally, sulfated-GAG synthesis was assessed by the incorporation of [(35)S]-inorganic sulfate. The bladders were analyzed by histochemical staining for HA and immunofluorescence for heparin sulfate and syndecan-4. RESULTS Urinary HA and sulfated-GAG were elevated after PS injection (P <0.05). A greater concentration of [(35)S]-labeled GAG in the PS group animals on the fifth day and, especially, on the seventh day represented increased GAG synthesis at these periods (P <0.05). Bladder sections from the PS group animals on day 1 showed a greater amount of HA in the urothelium. PS instillation damaged the urothelium layer of heparin sulfate and syndecan-4 seen in the control animals. On day 5, patchy areas of a restored layer were seen, and, on day 7, this layer had completely regenerated. CONCLUSIONS Urinary GAG cannot differentiate urothelial damage from recovery. Elevated levels of urinary GAG can result from either desquamation of the surface cell GAG layer or increased GAG synthesis to regenerate the damaged urothelium.

Bone deposition, bone resorption, and osteosarcoma

Bone deposition and bone resorption are ongoing dynamic processes, constituting bone remodeling. Some bone tumors, such as osteosarcoma (OS), stimulate focal bone deposition. OS is the most common primary bone tumor in children and young adults. A complex network of genes regulates bone remodeling and alterations in its expression levels can influence the genesis and progression of bone diseases, including OS. We hypothesized that the expression profiles of bone remodeling regulator genes would be correlated with OS biology and clinical features. We used real‐time PCR to evaluate the mRNA levels of the tartrate‐resistant acid phosphatase (ACP5), colony stimulating factor‐1 (CSF1R), bone morphogenetic protein 7 (BMP7), collagen, type XI, alpha 2 (COL11A2), and protein tyrosine phosphatases zeta 1 (PTPRZ1) genes, in 30 OS tumor samples and correlated with clinical and histological data. All genes analyzed, except CSF1R, were differentially expressed when compared with normal bone expression profiles. In our results, OS patients with high levels of COL11A2 mRNA showed worse overall (p = 0.041) and event free survival (p = 0.037). Also, a trend for better overall survival was observed in patients with samples showing higher expression of BMP7 (p = 0.067). COL11A2 overexpression and BMP7 underexpression could collaborate to OS tumor growth, through its central role in bone remodeling process.

MAPK7 and MAP2K4 as prognostic markers in osteosarcoma

Osteosarcoma is a class of cancer originating from the bone, affecting mainly children and young adults. Cytogenetic studies showed the presence of rearrangements and recurrent gains in specific chromosomal regions, indicating the possible involvement of genes located in these regions during the pathogenesis of osteosarcoma. These studies investigated expression of 10 genes located in the chromosomal region involved in abnormalities in osteosarcoma, 1p36, 17p, and chromosome 19. The purpose of this study was to investigate the expression profile of genes located in regions involved in chromosomal rearrangements in osteosarcoma. We used quantitative real-time polymerase chain reaction to investigate the expression of 10 genes located in 1p36.3 (MTHFR, ERRFI1, FGR, E2F2), 17p (MAPK7, MAP2K4), and chromosome 19 (BBC3, FOSB, JUND, and RRAS), in 70 samples taken from 30 patients (30 prechemotherapy, 30 postchemotherapy, and 10 metastases specimens) and 10 healthy bones as a control sample. The most interesting results showed a strong association between the expression levels of MAPK7 and MAP2K4 genes and clinical parameters of osteosarcoma. Overexpression of these genes was significantly associated to a poor response to treatment (P = .0001 and P = .0049, respectively), tumor progression, and worse overall survival (P = .0052 and P = .0085, respectively), suggesting that MAPK7 and MAP2K4 could play an important role in osteosarcoma tumorigenesis. Thus, these genes could be good markers in assessing response to treatment and development of osteosarcoma.