No abstract

BackgroundOptimizing treatment through microarray-based molecular subtyping is a promising method to address the problem of heterogeneity in breast cancer; however, current application is restricted to prediction of distant recurrence risk. This study investigated whether breast cancer molecular subtyping according to its global intrinsic biology could be used for treatment customization.MethodsGene expression profiling was conducted on fresh frozen breast cancer tissue collected from 327 patients in conjunction with thoroughly documented clinical data. A method of molecular subtyping based on 783 probe-sets was established and validated. Statistical analysis was performed to correlate molecular subtypes with survival outcome and adjuvant chemotherapy regimens. Heterogeneity of molecular subtypes within groups sharing the same distant recurrence risk predicted by genes of the Oncotype and MammaPrint predictors was studied.ResultsWe identified six molecular subtypes of breast cancer demonstrating distinctive molecular and clinical characteristics. These six subtypes showed similarities and significant differences from the Perou-Sørlie intrinsic types. Subtype I breast cancer was in concordance with chemosensitive basal-like intrinsic type. Adjuvant chemotherapy of lower intensity with CMF yielded survival outcome similar to those of CAF in this subtype. Subtype IV breast cancer was positive for ER with a full-range expression of HER2, responding poorly to CMF; however, this subtype showed excellent survival when treated with CAF. Reduced expression of a gene associated with methotrexate sensitivity in subtype IV was the likely reason for poor response to methotrexate. All subtype V breast cancer was positive for ER and had excellent long-term survival with hormonal therapy alone following surgery and/or radiation therapy. Adjuvant chemotherapy did not provide any survival benefit in early stages of subtype V patients. Subtype V was consistent with a unique subset of luminal A intrinsic type. When molecular subtypes were correlated with recurrence risk predicted by genes of Oncotype and MammaPrint predictors, a significant degree of heterogeneity within the same risk group was noted. This heterogeneity was distributed over several subtypes, suggesting that patients in the same risk groups require different treatment approaches.ConclusionsOur results indicate that the molecular subtypes established in this study can be utilized for customization of breast cancer treatment.

An optimal platelet-count threshold for prophylactic platelet transfusion in hematopoietic stem cell transplant (HSCT) recipients has yet to be determined. Between July 1997 and December 1999, we performed the first prospective randomized clinical trial addressing this issue in 159 HSCT recipients who received a prophylactic platelet transfusion when the morning platelet count fell below a 10,000/microL (10K) or 20,000/microL (20K) threshold. Subsequent prophylactic transfusions were administered according to a predetermined algorithm. The number of prophylactic and therapeutic transfusions and the incidence of minor and major bleeding were compared between the 2 groups. The groups were matched according to patient and transplantation characteristics. There were no significant differences in bleeding incidence or severity. Fourteen percent of patients in the 10K arm compared to 17% in the 20K arm had major bleeding events. Only 3 central nervous system bleeds occurred, 2 in the 10K group and 1 in the 20K group. No deaths were attributed to bleeding. An average of 11.4 days of bleeding occurred in both groups. An average of 10.4 platelet transfusions per patient were administered in the 10K group compared to 10.2 in the 20K group (P = .94). More transfusions were given above the assigned transfusion threshold in the 10K group than in the 20K group (4.3/patient versus 1.9/patient, respectively, P = .05). Safety measures incorporated into our study may have precluded demonstration of significant differences in platelet use between the groups. In conclusion, a platelet transfusion trigger of 10K was found to be safe; however, a decrease in platelet use was not achieved because of safety measures incorporated into our study design.

The autoimmune regulator (AIRE) protein is a putative transcription regulator with two plant homeodomain-type zinc fingers, a putative DNA-binding domain (SAND), and four nuclear receptor binding LXXLL motifs. We have shown here that in vitro, recombinant AIRE can form homodimers and homotetramers that were also detected in thymic protein extracts. Recombinant AIRE also oligomerizes spontaneously upon phosphorylation by cAMP dependent protein kinase A or protein kinase C. Similarly, thymic AIRE protein is phosphorylated at the tyrosine and serine/threonine residues. AIRE dimers and tetramers, but not the monomers, can bind to G-doublets with the ATTGGTTA motif and the TTATTA-box. Competition assays revealed that sequences with one TTATTA motif and two tandem repeats of ATTGGTTA had the highest binding affinity. These findings demonstrate that AIRE is an important DNA binding molecule involved in immune regulation.Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), 1 also known as autoimmune polyglandular syndrome type 1 (APS1), is a rare autosomal recessive disorder common in isolated populations such as Finns, Sardinians, and Iranian Jews (1). This syndrome is characterized by destructive autoimmune diseases of the endocrine organs, chronic candidiasis of mucous membranes, and ectodermal disorders. APECED is caused by mutations in the autoimmune regulator (AIRE) gene on chromosome 21q22.3 (2-4). The AIRE gene has recently been cloned by two independent groups of investigators (5, 6). The AIRE gene consists of 14 exons coding for a 2445-base pair mRNA transcript, and the translated product is expected to have 545 amino acids with a predicted molecular mass of 57.5 kDa. The predicted AIRE protein has several domains indicative of a transcriptional regulator protein (6). AIRE harbors two zinc fingers of plant homeodomain (PHD) type. A putative DNA binding domain named SAND as well as four nuclear receptor binding LXXLL motifs, an inverted LXXLL domain, and a variant of the latter (FXXLL) hint that this protein functions as a transcription coactivator (5-7). Furthermore, a highly conserved N-terminal 100-amino acid domain in AIRE has a significant homology to the homogenously staining (HSR) domain of Sp100 and Sp140 proteins (7). This domain has been shown to function as a dimerization domain in several Sp-100 related proteins (8). At the subcellular level, AIRE can be found in the cell nucleus in a speckled pattern in domains resembling promyelocytic leukemia nuclear bodies, also known as ND10, nuclear dots, or potential oncogenic domains, associated with the AIRE homologous nuclear proteins Sp100, Sp140, and Lysp100 (9).Interestingly, it has recently been shown that AIRE can activate transcription from a reporter gene when fused to a heterologous DNA binding domain. This activation required the full-length protein or the presence of more than one activation domain. A glutathione S-transferase pull-down assay showed that AIRE formed homodimers in vitro, probably through the N-terminal domain (...