Macrophage immunomodulation through new polymers that recapitulate functional effects of itaconate as a power house of innate immunity.

Itaconate (ITA) is an emerging powerhouse of innate immunity with therapeutic potential that is limited in its ability to be administered in a soluble form. We developed a library of polyester materials that incorporate ITA into polymer backbones resulting in materials with inherent immunoregulatory behavior. Harnessing hydrolytic degradation release from polyester backbones, ITA polymers resulted in the mechanism specific immunoregulatory properties on macrophage polarization in vitro. In a functional assay, the polymer-released ITA inhibited bacterial growth on acetate. Translation to an in vivo model of biomaterial associated inflammation, intraperitoneal injection of ITA polymers demonstrated a rapid resolution of inflammation in comparison to a control polymer silicone, demonstrating the value of sustained biomimetic presentation of ITA.

Prognostic-significance of p53 mutations in small non-cleaved cell lymphomas.

We have assessed the prognostic significance of mutations in the p53 tumor suppressor gene in patients with small non-cleaved cell lymphomas. In this retrospective pilot study we have, been able to evaluate the response to therapy of 21 previously untreated patients. Seven of these patients (33%) had tumors which contained a p53 mutation at presentation. Five of the 7 patients with mutant p53 relapsed and 4 died of progressive disease whereas none of the patients with wild type p53 relapsed and none died of progressive disease. These preliminary results strongly suggest that the presence of a mutated p53 gene is an unfavorable prognostic factor. p53 mutations could be used as a parameter in risk-adapted therapy protocols, or could even provide an appropiate target for therapy.

A prospective randomized evaluation of three schedules of mesna administration in patients receiving an ifosfamide-containing chemotherapy regimen: sustained efficiency and simplified administration.

Chemotherapy with oxazaphosphorines, such as ifosfamide, is often limited by unacceptable urotoxicity. Without uroprotection hemorrhagic cystitis becomes dose-limiting. Mesna, a thiol compound, is a drug able to bind the toxic metabolites, forming nontoxic compounds in the urine. A total of 122 patients were enrolled in this study and 228 chemotherapy cycles with an ifosfamide-containing regimen were performed (225 evaluable). Mesna was given at the same total dose as the ifosfamide in all arms. On arm A, mesna was given i. v. in equal doses 15 min before and 4 h and 8 h following the ifosfamide dose. On arm B, mesna was given in three equivalent doses 15 min before (i.v.) and 4 h (i.v.) and 8 h (p.o., double dose) following ifosfamide. On arm C, mesna was given i.v. in two equal doses given 15 min before and 4 h following. The incidence of urotoxicity was very low (lower than 15%) in the three arms, 0% in A, 1.36% in B and 2.70% in C. All three arms were equally efficient. Schedule C was considered superior to the others, since it was equally effective, simpler and more convenient.

Correlation of pathologic features with clinical outcome in pediatric adrenocortical neoplasia. A study of a Brazilian population. Brazilian Group for Treatment of Childhood Adrenocortical Tumors.

Although the relationship between pathologic features and clinical outcome is well established in adult adrenocortical neoplasms, the prognostic value of these features in pediatric adrenocortical neoplasms (PACN) is unclear. In a series of PACNs from 54 Brazilian children, the authors retrospectively investigated the prognostic value of histologic classification, ploidy, proliferative index, and size (as tumor weight or greater diameter). Histologic classification was most predictive of clinical behavior: there were no failures in 11 adenomas, 5 failures in 27 low-grade carcinomas, and 9 failures in 16 high-grade carcinomas (P = .0003). Tumor weight was predictive of failure in tumors weighing > or = 100 versus < 100 g (P = .04), and a trend was found toward failure among tumors measuring > or = 5 cm, as opposed to those < 5 cm (P = .07). Proliferative index was marginally related to failure (P = .05 at < 11% vs. > or = 11% and .07 at < 10% vs. > or = 10%), and ploidy was not significantly predictive of outcome (P = .25). Histologic type and tumor weight were the most reliable predictors of outcome in PACN.

Pre-operative control of arterial hypertension using ketoconazole in pediatric patients with adrenocortical tumors.

Adrenocortical tumors are rare in childhood, appearing more frequently in some regions such as South and South-eastern regions of Brazil and India. Common clinical signs include virilization, Cushing's syndrome, feminization and hypertension, either isolated or in association. The aim of this report is to present our experience with the pre-operative use of ketoconazole in children with an adrenocortical tumor to control elevated blood pressure levels non-responsive to the usual treatment. Over the last 16 years, of 46 children diagnosed as having adrenocortical tumor, 17 developed hypertension (diastolic pressure greater than the 95th percentile for age and sex according to data from the Task Force on Blood Pressure Control in Children), associated with virilization and/or Cushing's syndrome. In three of these 17 patients, conventional antihypertensive therapy failed, and they were treated with ketoconazole (200-300 mg/day). This resulted in rapid control of the blood pressure. It is concluded that in selected patients, ketoconazole may be useful adjuvant therapy for the palliative control of the arterial hypertension secondary to adrenocortical tumors, without side effects.

Pediatric oncology in Brazil.

Brazil is a country with many contrasts. This can help the understanding of environmental factors influencing the incidence of different cancers. The standard treatment and results achieved in certain areas of the country are not encountered in others. The establishment of national cooperative groups has helped the improvement. The subspecialty has been recognized and training programs are available. Many scientific achievements have been developed and are described.

Pediatric osteosarcoma. Successful retreatment of relapsed primary tumor and soft tissue recurrence with intraarterial cis-diamminedichloroplatin-II.

Six patients with extremity osteosarcoma initially underwent successful treatment of the primary tumor with four to seven courses of intraarterial cis-diamminedichloroplatin-II (IA-CDP; 100 to 150 mg/m2/course). The primary tumors in two patients were then extirpated by limb salvage. However, a local soft tissue recurrence occurred in both patients several months later. The other four patients refused surgical intervention and later also developed local bony recurrences. Reinstatement of three to five courses of IA-CDP in all six patients induced a complete response in five. The local recurrences (bony and soft tissue) in all six patients were excised. This included limb-salvage procedures in three patients. Additional postoperative chemotherapy was administered. Four patients remain alive and continuously free of disease 3.5+ to 4.5+ years after retreatment with IA-CDP.

Median sternotomy for the resection of bilateral pulmonary metastases in children.

Childhood cancer often results in pulmonary metastases, and proper identification and prompt treatment of these lesions increases the survival of these patients. Between 21 May 1995 and 26 June 1996, nine children (five with osteosarcoma, two with Wilms' tumor, and one each with hepatoblastoma and an adrenocortical tumor) underwent median sternotomy at our institution for resection of bilateral pulmonary metastases. These five boys and four girls ranged in age from 2 to 16 years (median, 11 years). Identification and resection of metastases in all lobes of the lungs was greatly facilitated by the median sternotomy approach because both thoracic cavities were fully accessible. In each of five patients, as many as 23 metastases were removed using wedge resection or a stapling device. Multiple biopsies only were obtained from the four remaining patients, whose lesions were too numerous and diffuse for effective resection. All nine patients recovered uneventfully; the median hospitalization was 3 days (range, 2-5 days). We find that median sternotomy is a safe, effective, and relatively simple procedure for resecting bilateral pulmonary metastases in children with cancer.

Chemotherapy of medulloblastoma.

Recent advances in neurosurgical techniques and diagnostic imaging capabilities have facilitated gross total resection and accurate staging of disease extent in a greater proportion of patients. The addition of chemotherapy to surgery and craniospinal radiation has improved the outcome of patients diagnosed with medulloblastoma. Long-term follow-up studies have documented the neuroendocrine and neuropsychological deficits seen in the survivors. This paper reviews key studies using all three modalities over the past two decades and presents on-going therapeutic strategies using a risk-adapted approach. Further areas of basic research and evolving data on studies in relapsed patients are also briefly discussed.

Pseudomonas aeruginosa exoenzyme S induces transcriptional expression of proinflammatory cytokines and chemokines.

Pseudomonas aeruginosa infection of cystic fibrosis patients causes lung damage that is substantially orchestrated by cytokines. In this study, multi-gene probe analysis was used to characterize the ability of the P. aeruginosa mitogen, exoenzyme S, to induce proinflammatory and immunoregulatory cytokines and chemokines. Exoenzyme S strongly induced transcription of proinflammatory cytokines and chemokines (tumor necrosis factor alpha, interleukin-1alpha [IL-1alpha], IL-1beta, IL-6, IL-8, MIP-1alpha, MIP-1beta, MCP-1, RANTES, and I-309), modest transcription of immunoregulatory cytokines (IL-10 and IL-12p40), and weak transcription of Th1 cytokines (IL-2 and gamma interferon). The response occurred early and subsided without evolving over time. These data suggest that cells responding to exoenzyme S would rapidly express proinflammatory cytokines and chemokines that may contribute to pulmonary inflammation in cystic fibrosis.

Increased survival, limb preservation, and prognostic factors for osteosarcoma.

Preoperative intraarterial (IA) cisplatin (CDP) was administered to 92 patients with nonmetastatic osteosarcoma. The ages of the patients ranged from 4 to 28 years. Sixty-four patients (70%) received 2 or 3 preoperative courses and 28 (30%) received 4 or more. Sixty-two specimens were available for pathologic examination to assess the degree of tumor necrosis. More than 90% tumor destruction was observed in 16 of 42 patients (38%) who received 1 to 3 preoperative courses as opposed to 17 of 20 (85%) who received 4 or more courses. Patients who received 4 or more courses had a 2-fold probability of achieving more than 90% tumor necrosis, and 68% underwent conservative surgery. Of those who received 3 or less courses, 23% underwent conservative surgery. Postoperatively, patients were treated with intravenous (IV) CDP alternating with doxorubicin (ADR) (Adriamycin, Adria Laboratories, Columbus, OH). Pulmonary metastases developed in 36 patients, bone metastases in 2, and local recurrence in 6. Two patients died of cardiac failure without evidence of disease. Thus, 46 patients (50%) were continuously free of disease 18 to 78 months after diagnosis. Univariate and multivariate analyses showed that male sex, low grade preoperative chemotherapy-induced necrosis, and nonosteoblastic histologic condition were prognostic factors predictive of recurrence, while male sex and large tumor size were prognostic factors predictive of death. These results are comparable with those reported by other centers and are superior to our previous experiences that yielded survival rates of 5% to 10%. A substantial number of patients also had the opportunity to achieve tumor removal with conservative surgery.

Molecular epidemiology of Burkitt's lymphoma from South America: differences in breakpoint location and Epstein-Barr virus association from tumors in other world regions.

We have previously shown that the endemic (African) and sporadic (North American) forms of Burkitt's lymphoma (BL) differ at a molecular level. We have now extended our studies to the molecular epidemiology of BL in South America, specifically to two climatic regions: temperate (Argentina and Chile) and tropical (Brazil). We have examined the patterns of chromosomal breakpoint locations in 39 tumors with respect to geography and Epstein-Barr virus (EBV) association. The result of these analyses provide further support for the existence of pathogenetically distinct subtypes of BL in different world regions. The majority of breakpoints on chromosome 8 in South American BL (41%) occurred in the immediate flanking region of c-myc, ie, further 5' of the "typical" sporadic breakpoints, in the first exon/intron region, and further 3' of the "typical" endemic breakpoints, which are usually distant from c-myc. However, the distribution of breakpoints on chromosome 14 in tumors from the temperate and tropical regions of South America is similar to that observed in sporadic and endemic tumors. Interestingly, only one tumor with an unrearranged c-myc gene joined to the S mu region of chromosome 14 was observed. This combination was also rarely observed in our earlier series and presumably is either less readily generated by the mechanism that mediates 8;14 translocation or requires other, infrequent genetic changes to provide the necessary selective advantage for lymphomagenesis. The frequency of EBV association in South American BL (51%) is also intermediate with respect to tumors from the United States (30%) and Africa (100%). No correlation with the breakpoint location on chromosome 8 was discernable. Surprisingly, only 54% of tumors with breakpoint outside c-myc were EBV positive. This is in contrast to endemic tumors and suggests that any pathogenetic contribution of EBV is not dependent on breakpoint location, but is more likely to complement additional pathogenetic elements that differ in different world regions.

Selective surgical indication in the management of neutropenic children presenting with acute abdomen.

As the treatment of pediatric malignancies improves and survival increases, the diagnosis of acute abdomen in these patients also becomes more common. Nevertheless, the management of this condition is still controversial. The authors report their experience in treating 12 neutropenic children with acute abdomen. The charts of 12 neutropenic patients with a diagnosis of acute abdomen treated at Boldrini Children's Cancer Center in Campinas, Brazil, between 1991 and 1996, were reviewed. Therapeutic strategy included an initial period of bowel rest, general supportive measures, and broad-spectrum antibiotics while waiting for the neutrophil count to rise. Three patients recovered completely without surgery, 8 underwent late surgery without complications, and 1 died due to uncontrolled sepsis before surgery. The treatment of acute abdomen in neutropenic children remains controversial. As shown in the present series, an initial nonoperative approach with selective surgical indication appears to be safe and to yield good results. Supportive treatment, until the neutrophil count rises, followed by surgery, if necessary, appears to be a sound therapeutic approach for neutropenic children with acute abdomen.

Lipopolysaccharide-stimulated or granulocyte-macrophage colony-stimulating factor-stimulated monocytes rapidly express biologically active IL-15 on their cell surface independent of new protein synthesis.

Although IL-15 shares many of the biological activities of IL-2, IL-2 expression is primarily under transcriptional regulation, while the mechanisms involved in the regulation of IL-15 are complex and not completely understood. In the current study, we found that CD14(+) monocytes constitutively exhibit both IL-15 mRNA and protein. IL-15 protein was found stored intracellularly and stimulation of CD14(+) monocytes with either LPS or GM-CSF resulted in mobilization of IL-15 stores to the plasma membrane. This rapidly induced surface expression was the result of a translocation of preformed stores, confirming that posttranslational regulatory stages limit IL-15, because it was not accompanied by an increase in IL-15 mRNA and occurred independent of de novo protein synthesis. After fixation, activated monocytes, but not resting monocytes, were found to support T cell proliferation, and this effect was abrogated by the addition of an IL-15-neutralizing Ab. The presence of preformed IL-15 stores and the ability of stimulated monocytes to mobilize these stores to their surface in an active form is a novel mechanism of regulation for IL-15.