No evidence that G6PD deficiency affects the efficacy or safety of daunorubicin in acute lymphoblastic leukemia induction therapy.

BACKGROUND/OBJECTIVES: Anthracyclines are used in induction therapy of pediatric acute lymphoblastic leukemia (ALL) and are known to generate oxidative stress; whether this translates into enhanced antileukemic activity or hemolytic effects in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency is unknown. DESIGN/METHODS: Among 726 pediatric patients with newly diagnosed ALL treated at St. Jude Children's Research Hospital, 22 had deficient G6PD activity. We compared the prevalence of positive minimal residual disease (MRD) ≥1% at Day 15/Day 19 of induction or ≥0.01% at Day 42/Day 46 (end of induction) and the number of red blood cell (RBC) transfusions after daunorubicin in induction between patients with or without G6PD deficiency, adjusting for ALL risk group, treatment protocol, age, and gender. RESULTS: There was no difference in Day 15/19 (P = 1) or end of induction MRD (P = 0.76) nor in the number of RBC transfusions (P = 0.73); the lack of association with MRD was confirmed in a dataset of 1192 newly diagnosed male patients enrolled in a Children's Oncology Group trial (P = 0.78). CONCLUSION: We found no evidence that G6PD deficiency affects daunorubicin activity during induction treatment for ALL.

Exploring the clonal evolution of CD133/aldehyde-dehydrogenase-1 (ALDH1)-positive cancer stem-like cells from primary to recurrent high-grade serous ovarian cancer (HGSOC). A study of the Ovarian Cancer Therapy-Innovative Models Prolong Survival (OCTIPS) Consortium.

BACKGROUND: High-grade serous ovarian cancer (HGSOC) causes 80% of all ovarian cancer (OC) deaths. In this setting, the role of cancer stem-like cells (CSCs) is still unclear. In particular, the evolution of CSC biomarkers from primary (pOC) to recurrent (rOC) HGSOCs is unknown. Aim of this study was to investigate changes in CD133 and aldehyde dehydrogenase-1 (ALDH1) CSC biomarker expression in pOC and rOC HGSOCs. METHODS: Two-hundred and twenty-four pOC and rOC intrapatient paired tissue samples derived from 112 HGSOC patients were evaluated for CD133 and ALDH1 expression using immunohistochemistry (IHC); pOCs and rOCs were compared for CD133 and/or ALDH1 levels. Expression profiles were also correlated with patients' clinicopathological and survival data. RESULTS: Some 49.1% of the patient population (55/112) and 37.5% (42/112) pOCs were CD133+ and ALDH1+ respectively. CD133+ and ALDH1+ samples were detected in 33.9% (38/112) and 36.6% (41/112) rOCs. CD133/ALDH1 coexpression was observed in 23.2% (26/112) and 15.2% (17/112) of pOCs and rOCs respectively. Pairwise analysis showed a significant shift of CD133 staining from higher (pOCs) to lower expression levels (rOCs) (p < 0.0001). Furthermore, all CD133 + pOC patients were International Federation of Gynaecology and Obstetrics (FIGO)-stage III/IV (p < 0.0001) and had significantly worse progression-free interval (PFI) (p = 0.04) and overall survival (OS) (p = 0.02). On multivariate analysis, CD133/ALDH1 coexpression in pOCs was identified as independent prognostic factor for PFI (HR: 1.64; 95% CI: 1.03-2.60; p = 0.036) and OS (HR: 1.71; 95% CI: 1.01-2.88; p = 0.045). Analysis on 52 pts patients with known somatic BRCA status revealed that BRCA mutations did not influence CSC biomarker expression. CONCLUSIONS: The study showed that CD133/ALDH1 expression impacts HGSOC patients' survival and first suggests that CSCs might undergo phenotypic change during the disease course similarly to non stem-like cancer cells, providing also a first evidence that there is no correlation between CSCs and BRCA status.

Tyrosine kinome sequencing of pediatric acute lymphoblastic leukemia: a report from the Children's Oncology Group TARGET Project.

One recently identified subtype of pediatric B-precursor acute lymphoblastic leukemia (ALL) has been termed BCR-ABL1-like or Ph-like because of similarity of the gene expression profile to BCR-ABL1 positive ALL suggesting the presence of lesions activating tyrosine kinases, frequent alteration of IKZF1, and poor outcome. Prior studies demonstrated that approximately half of these patients had genomic lesions leading to CRLF2 overexpression, with half of such cases harboring somatic mutations in the Janus kinases JAK1 and JAK2. To determine whether mutations in other tyrosine kinases might also occur in ALL, we sequenced the tyrosine kinome and downstream signaling genes in 45 high-risk pediatric ALL cases with either a Ph-like gene expression profile or other alterations suggestive of activated kinase signaling. Aside from JAK mutations and 1 FLT3 mutation, no somatic mutations were found in any other tyrosine kinases, suggesting that alternative mechanisms are responsible for activated kinase signaling in high-risk ALL.

After insufficient radiofrequency ablation, tumor-associated endothelial cells exhibit enhanced angiogenesis and promote invasiveness of residual hepatocellular carcinoma.

BACKGROUND: The mechanism regarding rapid progression of residual hepatocellular carcinoma (HCC) after insufficient radiofrequency ablation (RFA) has been preliminarily discussed. However, most studies have mainly focused on RFA-induced changes in the tumor cells. The present study was designed to determine whether tumor-associated endothelial cells (TAECs) could contribute to the invasiveness of HCC after insufficient RFA. METHODS: TAECs were isolated from fresh HCC tissue and characterized. Morphological changes were observed in TAECs after heat treatment for 10 min. TAEC proliferation, migration and tube formation after heat treatment for 10 min at 37°C (control group), and 42 and 47°C (insufficient RFA groups) were examined. The differences in TAECs interactions with HepG2-GFP or HCCLM3-GFP cells among the two insufficient RFA groups and control group were evaluated. The expression of E-selectin, ICAM-1 and VCAM-1 in TAECs was measured. The effects of TAECs on the invasiveness of HepG2-GFP or HCCLM3-GFP cells after insufficient RFA were analyzed. The IL-6, IL-8, MCP-1 and GRO-α concentrations in conditioned medium from TAECs were measured after insufficient RFA. The associated signaling pathways of Akt, ERK1/2, STAT3 and NF-κB were analyzed in TAECs after insufficient RFA. RESULTS: TAECs expressed the EC-specific markers and took up complexes of Dil-Ac-LDL. Relative to the control group, the proliferation of TAECs was significantly inhibited and their migration and tube formation were significantly enhanced in the insufficient RFA groups. Significantly more HepG2-GFP or HCCLM3-GFP cells adhered to TACEs in these groups than in the control group (all P<0.001), via up-regulated expression of E-selectin, ICAM-1 and VCAM-1. TAECs promoted the invasiveness of HepG2-GFP or HCCLM3-GFP cells after insufficient RFA via the up-regulation of IL-6, IL-8, MCP-1 and GRO-α in conditioned medium (all P<0.05). Insufficient RFA enhanced the activities of Akt, ERK1/2 and NF-κB signaling pathways and inhibited STAT3 signaling pathways. CONCLUSIONS: Insufficient RFA enhanced TAEC migration and tube formation, and this may play a key role in the rapid growth of residual HCC. Increased expression of metastasis-related molecules in TAECs after insufficient RFA may be a potential mechanism for the metastasis of residual HCC.

Excision repair cross-complementation group 1 protein overexpression as a predictor of poor survival for high-grade serous ovarian adenocarcinoma.

OBJECTIVE: The excision repair cross-complementation group 1 (ERCC1) expression is a predictor of survival after surgical treatment for several malignancies. Its overexpression has been reported as a marker of platinum resistance in lung cancer. However, the relevance of ERCC1 expression in ovarian cancer (OC) is the subject of controversy, both as a predictive parameter for platinum resistance and because of its association with poor prognosis. Therefore, we performed a retrospective study investigating ERCC1 expression and its correlation with patients' survival in OC. METHODS: We analyzed the ERCC1 protein expression using four different ERCC1 antibodies (clone 8F1) with different staining protocols. Immunohistochemistry was performed on multi-tissue microarrays (77 patients with primary serous ovarian cancer treated between 1999 and 2004; median age at diagnosis 67 years; range 32 to 88 years; 90% FIGO III+IV). In all cases cytoreductive surgery was followed by platinum-based chemotherapy. RESULTS: The Kaplan-Meier analysis revealed that the survival of patients with ERCC1-negative OCs (n=45; 62%) was significantly better (median survival 50.0 months) compared with the ERCC1-positive group (n=32; 38%; 20 months; p=0.004). Furthermore, ERCC1 expression was of prognostic relevance (p=0.002) in the case of negative expression in patients with residual tumor, where a higher survival rate was observed (median survival 30 months compared to 7.8 months in the ERCC1-positive group). CONCLUSIONS: ERCC1 protein overexpression may act as a prognostic marker for poor survival of high-grade OC even in patients operated with residual disease.

Dihydropyrimidine dehydrogenase mRNA expression in peripheral blood of rectal cancer patients is significantly associated with residual tumor and distant metastases following resection.

BACKGROUND: DPD and TS expression have been shown to correlate with response of 5-FU based chemotherapy in colorectal cancer tissue. Little is known about mRNA expression levels of TS and DPD in peripheral blood. The goals of this study were to test the feasibility of DPD and TS detection in blood and their associations to TNM staging and complete surgical resection. METHODS: Whole blood was drawn 1 day pre- and 10 days post-operatively from 23 patients with rectal cancer. Either adjuvant (n = 15) or neoadjuvant (n = 8) treatment was performed. Tumor cells were enriched from whole blood by density gradient centrifugation prior to extraction of total cellular RNA and subsequent direct quantitative reverse transcriptase-PCR assays. RESULTS: DPD was detectable in 21/23 patients (91.3%) and TS in 14/23 (61.7%). Stepwise multiple linear regression models showed a significant association of DPD expression with distant metastases (P = 0.004) and residual tumor categories (P = 0.03). CONCLUSIONS: Quantitative analysis of TS and DPD mRNA expression in peripheral blood of rectal cancer patients is technically feasible. DPD expression levels appear to be associated with residual tumor categories and might serve as a molecular marker for complete tumor resection. Larger studies seem to be warranted to scrutinize our hypothesis.

Retention but significant reduction of BCR-ABL transcript in hematopoietic stem cells in chronic myelogenous leukemia after imatinib therapy.

Chronic myelogenous leukemia (CML) is effectively treated with imatinib mesylate (IM), a small molecule inhibitor of the BCR-ABL tyrosine kinase that is expressed in the entire hematopoietic compartment including stem cells (HSC) and progenitors in CML patients. While IM induces disease remission, it does not appear to eradicate BCR-ABL-positive stem cells. We investigated the residual CML cells in HSC and myeloid progenitors isolated using fluorescence-activated cell sorting after IM-therapy. Quantitative real-time polymerase chain reaction detecting BCR-ABL transcripts showed that CML progenitors were eradicated within 12 months while the BCR-ABL-positive HSC remained. However, IM-therapy continuation could significantly decrease the ratio of BCR-ABL to BCR also in the HSC population. Our results implicate that the sorted and purified stem cells are useful for more sensitive quantification of BCR-ABL-positive minimal residual disease.

Overexpression of orphan receptor tyrosine kinase Ror1 as a putative tumor-associated antigen in Iranian patients with acute lymphoblastic leukemia.

Receptor tyrosine kinases (RTKs) are a group of enzymes involved in a variety of physiological and pathological processes. The human Ror1 is a member of the RTK family with unknown ligand and biological function. Overexpression of Ror1 has recently been reported in B-cell chronic lymphocytic leukemia. The aim of this study was to explore the expression profile of Ror1 in acute lymphoblastic leukemia (ALL) cells. Therefore, leukemic cells were isolated from the bone marrow and/or peripheral blood (PB) of 57 ALL patients. Immunophenotyping was performed by flow cytometry and mRNA expression was detected by RT-PCR. Overexpression of Ror1 mRNA was detected in 23 of 57 (40%) ALL patients. A similar expression pattern was observed in ALL cell lines, with 4 of 12 (33%) being positive. Stimulation of normal PB mononuclear cells with pokeweed mitogen and phorbol myristate acetate induced substantially higher Ror1 mRNA expression compared to unstimulated cultured cells. There has been neither a significant association between Ror1 expression and the immunophenotypic profile of the leukemic cells, nor with other clinical or hematological features of the patients. In conclusion, our findings propose Ror1 as a new tumor-associated antigen and a potential tool for targeted immunotherapy and monitoring of minimal residual disease in ALL.

Quantitation of minimal residual disease in acute myeloid leukemia by tryptase monitoring identifies a group of patients with a high risk of relapse.

PURPOSE: Recent data suggest that tryptase is produced by blast cells in a group of patients with acute myeloid leukemia (AML). In these patients, serum tryptase levels are elevated at diagnosis and decrease to normal (<15 ng/mL) or near normal values in those achieving complete hematologic remission (CR) after chemotherapy. PATIENTS: In this study, we examined the value of tryptase as a marker of minimal residual AML. In 61 patients with de novo AML exhibiting elevated serum tryptase (>15 ng/mL) at diagnosis, tryptase levels were measured serially during and after chemotherapy by a fluoroenzyme immunoassay. RESULTS: Of the 61 patients, 42 (68.9%) entered hematologic CR in response to induction chemotherapy. Twenty-nine of these 42 patients also entered biochemical remission (BR) defined by a decrease of tryptase levels to normal (<15 ng/mL). The remaining 13 patients exhibited elevated enzyme levels despite of hematologic CR. As assessed by multivariate analysis, the elevated tryptase in CR was found to be an independent prognostic variable concerning disease-free survival. Thus, AML relapses occurred in 15 of 29 patients with CR + BR (52%) and in 12 of 13 patients with CR without BR (92%), resulting in a significantly reduced probability of continuous CR for patients with CR without BR (P < 0.05). In all patients with continuous hematologic CR, tryptase levels remained constantly normal, whereas a recurrent elevation of tryptase in CR was invariably followed by a hematologic relapse. CONCLUSION: A persistently elevated tryptase level in AML in CR is indicative of minimal residual AML and associated with a high risk of relapse.

Quantitation of GD2 synthase mRNA by real-time reverse transcriptase polymerase chain reaction: clinical utility in evaluating adjuvant therapy in neuroblastoma.

PURPOSE: Minimal residual disease (MRD) is one of the final hurdles to cancer cure. Because therapy (myeloablation, immunotherapy, or differentiation) for MRD is applied at the time of clinical remission, objective surrogate markers are needed to gauge treatment efficacy. PATIENTS AND METHODS: Using quantitative reverse transcriptase polymerase chain reaction (RT-PCR) of GD2 synthase (beta1,4-N-acetylgalactosaminyltransferase, EC 2.4.1.92) mRNA, we evaluated MRD response to anti-GD2 monoclonal antibody 3F8 adjuvant therapy, namely, one cycle of radioimmunotherapy using iodine-131 ((131)I)-3F8 plus one cycle of unlabeled 3F8 in 45 stage 4 neuroblastoma patients (newly diagnosed or without prior relapse) on the N7 protocol at Memorial Sloan-Kettering Cancer Center. The prognostic effect of MRD in their bone marrows before and after this phase of adjuvant therapy on progression-free survival (PFS) and overall survival (OS) was also analyzed. RESULTS: Before 3F8 treatment, 24 of 45 patients were in complete remission (CR), 12 were in very good partial remission (VGPR), and nine were in partial remission (PR), according to criteria from International Neuroblastoma Staging System plus (131)I-3F8 scan; 71% had detectable tumor cells in marrow by real-time RT-PCR. Of the 32 positive patients, 20 became negative after therapy, with a 63% efficacy. When patients were stratified by CR/VGPR versus PR, GD2 synthase positivity was prognostic when detected before 3F8-targeted therapy (PFS, P =.045 and OS, P =.010). Persistent marker positivity was also predictive of PFS (P =.035) and OS (P =.027). Patients who succumbed to the disease had transcript levels four times higher than those who remain alive. CONCLUSION: GD2 synthase mRNA is a useful surrogate marker for evaluating adjuvant treatment efficacy in neuroblastoma with prognostic potential.