Jane L. Meza

Analysis of Prognostic Factors in Patients With Nonmetastatic Rhabdomyosarcoma Treated on Intergroup Rhabdomyosarcoma Studies III and IV: The Children's Oncology Group

PURPOSE The outcome for localized rhabdomyosarcoma (RMS) or undifferentiated sarcoma (UDS) is affected by age, histology, primary anatomic site, extent of disease, and therapy. PATIENTS AND METHODS We evaluated patient and disease characteristics for their ability to predict outcome for patients with nonmetastatic RMS or UDS treated on Intergroup Rhabdomyosarcoma Study (IRS) -III (1984 to 1991) or IRS-IV (1991 to 1997). RESULTS The estimated 5-year failure-free survival (FFS) rate was 90% for patients with embryonal RMS (ERMS) stage 1, group I or IIa; stage 2, group I; or group III orbit. The estimated 5-year FFS rate was 87% for patients with ERMS stage 1, group IIb or IIc; stage 1, group III nonorbit; stage 2, group II; and stage 3, group I or II; and 73% for patients with ERMS stage 2 or 3, group III. The estimated 5-year FFS rate was poor for patients with stage 2 or 3, group III ERMS with invasive (T2) tumors who were age younger than 1 year or 10 years or older (56%) and patients with stage 2 or 3, group III extremity primary tumors (43%). Overall, outcomes for patients with alveolar RMS (ARMS) or UDS were worse than for patients with ERMS. However, the 5-year FFS rate was good for patients with ARMS/UDS at favorable sites with group I or II (80%) or group III (76%) disease. The FFS rate was poorer for patients with ARMS/UDS at unfavorable sites with group I or II (66%) or group III (45%) disease. The estimated 5-year FFS rate was 31% for patients with group III ARMS/UDS at unfavorable sites with regional lymph node disease, which is similar to metastatic RMS. CONCLUSION Patient and disease characteristics identify distinct subsets with different outcomes, allowing the Soft Tissue Sarcoma Committee of the Childrens Oncology Group to refine risk-adapted therapy assignment.

Evidence that a burst of DNA depurination in SENCAR mouse skin induces error-prone repair and forms mutations in the H-ras gene.

Treatment of SENCAR mouse skin with dibenzo[a,l]pyrene results in abundant formation of abasic sites that undergo error-prone excision repair, forming oncogenic H-ras mutations in the early preneoplastic period. To examine whether the abundance of abasic sites causes repair infidelity, we treated SENCAR mouse skin with estradiol-3,4-quinone (E2-3,4-Q) and determined adduct levels 1 h after treatment, as well as mutation spectra in the H-ras gene between 6 h and 3 days after treatment. E2-3,4-Q formed predominantly (⩾99%) the rapidly-depurinating 4-hydroxy estradiol (4-OHE2)-1-N3Ade adduct and the slower-depurinating 4-OHE2-1-N7Gua adduct. Between 6 h and 3 days, E2-3,4-Q induced abundant A to G mutations in H-ras DNA, frequently in the context of a 3′-G residue. Using a T.G-DNA glycosylase (TDG)-PCR assay, we determined that the early A to G mutations (6 and 12 h) were in the form of G.T heteroduplexes, suggesting misrepair at A-specific depurination sites. Since G-specific mutations were infrequent in the spectra, it appears that the slow rate of depurination of the N7Gua adducts during active repair may not generate a threshold level of G-specific abasic sites to affect repair fidelity. These results also suggest that E2-3,4-Q, a suspected endogenous carcinogen, is a genotoxic compound and could cause mutations.

Results from the IRS-IV randomized trial of hyperfractionated radiotherapy in children with rhabdomyosarcoma--a report from the IRSG.

PURPOSE To evaluate the outcome and toxicity of hyperfractionated radiotherapy (HFRT) vs. conventionally fractionated radiotherapy (CFRT) in children with Group III rhabdomyosarcoma (RMS). METHODS AND MATERIALS Five hundred fifty-nine children were enrolled into the Intergroup Rhabdomyosarcoma Study IV with Group III RMS. Sixty-nine were ineligible for the analysis because of incorrect group or pathologic findings. Of the 490 remaining, 239 were randomized to HFRT (59.4 Gy in 54 1.1-Gy twice daily fractions) and 251 to CFRT (50.4 Gy in 28 1.8-Gy daily fractions). The age range was <1-21 years. All patients received chemotherapy. RT began at Week 9 after induction chemotherapy for all but those with high-risk parameningeal tumors who received RT during induction chemotherapy. The patient groups were equally balanced. The median follow-up was 3.9 years. RESULTS Analysis by randomized treatment assignment (intent to treat) revealed an estimated 5-year failure-free survival (FFS) rate of 70% and overall survival (OS) of 75%. In the univariate analysis, the factors associated with the best outcome were age 1-9 years at diagnosis; noninvasive tumors; tumor size <5 cm; uninvolved lymph nodes; Stage 1 or 2 disease; primary site in the orbit or head and neck; and embryonal histologic features (p = 0.001 for all factors). No differences in the FFS or OS between the two RT treatment methods and no differences in the FFS or OS between HFRT and CFRT were found when analyzed by age, gender, tumor size, tumor invasiveness, nodal status, histologic features, stage, or primary site. Treatment compliance differed by age. Of the children <5 years, 57% assigned to HFRT received HFRT and 77% assigned to CFRT received CFRT. Of the children >or=5 years, 88% assigned to both HFRT and CFRT received their assigned treatment. The reasons for not receiving the appropriate randomized treatment were progressive disease, early death, parent or physician refusal, young age, or surgery. The toxicity assessment revealed more mucositis with HFRT (66%) than with CFRT (46%) (p = 0.03) for the parameningeal patients, and more skin reactions (16%) and nausea/vomiting (13%) with HFRT than with CFRT (7% and 5%, respectively) for patients with nonparameningeal primary tumors (p = 0.03 and p = 0.02, respectively). The analysis by treatment actually received revealed a 5-year FFS rate of 73% and OS rate of 77%, with no difference between CFRT and HFRT. As well, there was no difference in FFS or OS between CFRT and HFRT when analyzed by age, gender, tumor size, tumor invasiveness, modal status, histology, stage or site of primary. The 5-year estimated cumulative incidence of failure for the irradiated patients was local, 13%; regional, 3%; and distant, 13%; with no differences between HFRT and CFRT. The 5-year local failure rate by site was orbit, 5%; head and neck, 12%; parameningeal, 16%; bladder/prostate, 19%; extremity, 7%; and all others, 14%. The 5-year regional failure rate was parameningeal,1%; extremity, 20%; and all others, 5%. The 5-year distant failure rate was orbit, 2%; head and neck, 6%; parameningeal, 11%; bladder/prostate, 15%; extremity, 28%; and all others, 17%. CONCLUSIONS HFRT, as given in this study, did not improve local/regional control, FFS, or OS compared with CFRT. The risk of local/regional failure was comparable to that of distant failure in children with Group III RMS. The standard of care for Group III RMS continues to be CFRT with chemotherapy.

Nonadherence to Oral Mercaptopurine and Risk of Relapse in Hispanic and Non-Hispanic White Children With Acute Lymphoblastic Leukemia: A Report From the Children's Oncology Group

PURPOSE Systemic exposure to mercaptopurine (MP) is critical for durable remissions in children with acute lymphoblastic leukemia (ALL). Nonadherence to oral MP could increase relapse risk and also contribute to inferior outcome in Hispanics. This study identified determinants of adherence and described impact of adherence on relapse, both overall and by ethnicity. PATIENTS AND METHODS A total of 327 children with ALL (169 Hispanic; 158 non-Hispanic white) participated. Medication event-monitoring system caps recorded date and time of MP bottle openings. Adherence rate, calculated monthly, was defined as ratio of days of MP bottle opening to days when MP was prescribed. RESULTS After 53,394 person-days of monitoring, adherence declined from 94.7% (month 1) to 90.2% (month 6; P < .001). Mean adherence over 6 months was significantly lower among Hispanics (88.4% v 94.8%; P < .001), patients age ≥ 12 years (85.8% v 93.1%; P < .001), and patients from single-mother households (80.6% v 93.1%; P = .001). A progressive increase in relapse was observed with decreasing adherence (reference: adherence ≥ 95%; 94.9% to 90%: hazard ratio [HR], 4.1; 95% CI,1.2 to 13.5; P = .02; 89.9% to 85%: HR, 4.0; 95% CI, 1.0 to 15.5; P = .04; < 85%: HR. 5.7; 95% CI, 1.9 to 16.8; P = .002). Cumulative incidence of relapse (± standard deviation) was higher among Hispanics (16.5% ± 4.0% v 6.3% ± 2.2%; P = .02). Association between Hispanic ethnicity and relapse (HR, 2.6; 95% CI, 1.1 to 6.1; P = .02) became nonsignificant (HR, 1.8; 95% CI, 0.6 to 5.2; P = .26) after adjusting for adherence and socioeconomic status. At adherence rates ≥ 90%, Hispanics continued to demonstrate higher relapse, whereas at rates < 90%, relapse risk was comparable to that of non-Hispanic whites. CONCLUSION Lower adherence to oral MP increases relapse risk. Ethnic difference in relapse risk differs by level of adherence-an observation currently under investigation.

MUC4 mucin potentiates pancreatic tumor cell proliferation, survival, and invasive properties and interferes with its interaction to extracellular matrix proteins

MUC4, a transmembrane mucin, is aberrantly expressed in pancreatic adenocarcinomas while remaining undetectable in the normal pancreas. Recent studies have shown that the expression of MUC4 is associated with the progression of pancreatic cancer and is inversely correlated with the prognosis of pancreatic cancer patients. In the present study, we have examined the phenotypic and molecular consequences of MUC4 silencing with an aim of establishing the mechanistic basis for its observed role in the pathogenesis of pancreatic cancer. The silencing of MUC4 expression was achieved by stable expression of a MUC4-specific short hairpin RNA in CD18/HPAF, a highly metastatic pancreatic adenocarcinoma cell line. A significant decrease in MUC4 expression was detected in MUC4-knockdown (CD18/HPAF-siMUC4) cells compared with the parental and scrambled short interfering RNA–transfected (CD18/HPAF-Scr) control cells by immunoblot analysis and immunofluorescence confocal microscopy. Consistent with our previous observation, inhibition of MUC4 expression restrained the pancreatic tumor cell growth and metastasis as shown in an orthotopic mouse model. Our in vitro studies revealed that MUC4-associated increase in tumor cell growth resulted from both the enhanced proliferation and reduced cell death. Furthermore, MUC4 expression was also associated with significantly increased invasiveness (P ≤ 0.05) and changes in actin organization. The presence of MUC4 on the cell surface was shown to interfere with the tumor cell-extracellular matrix interactions, in part, by inhibiting the integrin-mediated cell adhesion. An altered expression of growth- and metastasis-associated genes (LI-cadherin, CEACAM6, RAC1, AnnexinA1, thrombomodulin, epiregulin, S100A4, TP53, TP53BP, caspase-2, caspase-3, caspase-7, plakoglobin, and neuregulin-2) was also observed as a consequence of the silencing of MUC4. In conclusion, our study provides experimental evidence that supports the functional significance of MUC4 in pancreatic cancer progression and indicates a novel role for MUC4 in cancer cell signaling. (Mol Cancer Res 2007;5(4):309–20)

Up-Front Window Trial of Topotecan in Previously Untreated Children and Adolescents With Metastatic Rhabdomyosarcoma: An Intergroup Rhabdomyosarcoma Study

PURPOSE To investigate the antitumor activity and toxicity of topotecan, used alone and in combination with conventional therapy, in patients with metastatic rhabdomyosarcoma (RMS). PATIENTS AND METHODS Forty-eight patients younger than 21 years of age with newly diagnosed metastatic RMS received 2.0 to 2.4 mg/m(2) of topotecan intravenously daily for 5 days every 21 days before standard therapy. Two courses were given in the absence of progressive disease or excessive toxicity and response was assessed. Patients with at least a partial response (PR) to topotecan proceeded to therapy with alternating courses of vincristine 1.5 mg/m(2), dactinomycin 1.5 mg/m(2), and cyclophosphamide 2.2 g/m(2) (VAC) and vincristine 1.5 mg/m(2), topotecan 0.75 mg/m(2) daily x 5, and cyclophosphamide 250 mg/m(2) daily x 5. Patients who did not respond to topotecan received continuation therapy with VAC alone. RESULTS The overall response rate to topotecan was 46% (complete response, 4%; partial response 42%). Unexpectedly, patients with alveolar RMS had a higher rate of response (65%) than those with embryonal RMS (28%; P: = .08). The most common grade 3 or 4 toxicities were neutropenia (67%), anemia (33%), thrombocytopenia (25%), and infection (21%). Two-year failure-free survival and survival estimates were 24% and 46%, respectively. Response to window therapy did not correlate with survival. CONCLUSION The high response rate and acceptable toxicity profile of topotecan in children with advanced RMS support further evaluation of this agent in phase III trials. The superior responses in alveolar RMS are of interest.

Availability and Use of Palliative Care and End-of-Life Services for Pediatric Oncology Patients

PURPOSE Palliative care prevents or relieves the symptoms caused by life-threatening medical conditions. Previous surveys have shown both underuse and lack of availability of these services for children with cancer throughout North America. We sought to investigate the current practices and resources surrounding palliative and end-of-life care among participating institutions of the Childrens Oncology Group (COG). METHODS A survey regarding practices and resources was developed by the COG palliative care subcommittee and was sent to all 232 institutions to complete for the calendar year 2005. RESULTS The survey was completed by 81% of the institutions. Per institution, there were a mean of 64.6 newly diagnosed patients and 17.7 patients experiencing relapse. A palliative care team was available in 58% of institutions, a pain service in 90%, a hospice in 60%, a psychosocial support team in 80%, and a bereavement program in 59%. Complementary and alternative medicine was available in 39% of institutions and in 95% of the COG institutions community. Most services, even when available, were not well used by patients. CONCLUSION Despite the well-established benefit of pediatric palliative care, it is only offered in 58% of COG institutions caring for children with cancer. In an era where the benefit of palliative care has been clearly established, this number should approach 100%. Efforts should be directed toward understanding barriers to provision of such services, so that they are available and well used at all childhood cancer centers.

The molecular etiology of breast cancer: evidence from biomarkers of risk.

Estrogens can become endogenous carcinogens via formation of catechol estrogen quinones, which react with DNA to form specific depurinating estrogen‐DNA adducts. The mutations resulting from these adducts can lead to cell transformation and the initiation of breast cancer. Estrogen metabolites, conjugates and depurinating DNA adducts in urine samples from 46 healthy control women, 12 high‐risk women and 17 women with breast cancer were analyzed. The estrogen metabolites, conjugates and depurinating DNA adducts were identified and quantified by using ultraperformance liquid chromatography/tandem mass spectrometry. The levels of the ratios of depurinating DNA adducts to their respective estrogen metabolites and conjugates were significantly higher in high‐risk women (p < 0.001) and women with breast cancer (p < 0.001) than in control subjects. The high‐risk and breast cancer groups were not significantly different (p = 0.62). After adjusting for patient characteristics, these ratios were still significantly associated with health status. Thus, the depurinating estrogen‐DNA adducts are possible biomarkers for early detection of breast cancer risk and response to preventive treatment.

MUC4 Mucin Interacts with and Stabilizes the HER2 Oncoprotein in Human Pancreatic Cancer Cells

MUC4, a high-molecular weight transmembrane glycoprotein, is overexpressed in pancreatic cancer and is implicated in its pathogenesis. It is a heterodimeric protein containing a large extracellular, heavily glycosylated subunit, MUC4alpha, and a transmembrane growth factor-like subunit, MUC4beta. In the present study, we have shown the interaction of human MUC4 with the receptor tyrosine kinase HER2 in pancreatic adenocarcinoma cells by reciprocal coimmunoprecipitation and cocapping studies. MUC4 colocalized with HER2 at the cell surface and in the cytoplasm. Silencing of MUC4 by transient or stable expression of MUC4-targeted short-interfering RNA led to the down-regulation of HER2 with a concomitant decrease in its phosphorylated form (pY(1248)-HER2). Further analyses revealed that the MUC4-knockdown-mediated decrease in HER2 expression occurred due to the drop in the stability of the receptor. In MUC4-knockdown pancreatic cancer cells, we also observed a reduced phosphorylation of the focal adhesion kinase and p42/44 mitogen-activated protein kinase, which are downstream effector proteins in HER2 signaling. Our findings add a new dimension to MUC4 function as a modulator of cell signaling and provide mechanistic evidence for its role in pancreatic cancer progression.

CD4+ Regulatory and Effector/Memory T Cell Subsets Profile Motor Dysfunction in Parkinson’s Disease

Animal models and clinical studies have linked the innate and adaptive immune system to the pathology of Parkinson’s disease (PD). Despite such progress, the specific immune responses that influence disease progression have eluded investigators. Herein, we assessed relationships between T cell phenotype and function with PD progression. Peripheral blood lymphocytes from two separate cohorts, a discovery cohort and a validation cohort, totaling 113 PD patients and 96 age- and environment-matched caregivers were examined by flow cytometric analysis and T cell proliferation assays. Increased effector/memory T cells (Tem), defined as CD45RO+ and FAS+ CD4+ T cells and decreased CD31+ and α4β7+ CD4+ T cells were associated with progressive Unified Parkinson’s Disease Rating Scale III scores. However, no associations were seen between immune biomarkers and increased age or disease duration. Impaired abilities of regulatory T cells (Treg) from PD patients to suppress effector T cell function was observed. These data support the concept that chronic immune stimulation, notably Tem activation and Treg dysfunction is linked to PD pathobiology and disease severity, but not disease duration. The association of T cell phenotypes with motor symptoms provides fresh avenues for novel biomarkers and therapeutic designs.