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Background: Spinal muscular atrophy type 1 (SMA1) is a progressive, monogenic motor neuron disease with an onset during infancy that results in failure to achieve motor milestones and in death or the need for mechanical ventilation by 2 years of age. We studied functional replacement of the mutated gene encoding survival motor neuron 1 (SMN1) in this disease.Methods: Fifteen patients with SMA1 received a single dose of intravenous adeno-associated virus serotype 9 carrying SMN complementary DNA encoding the missing SMN protein. Three of the patients received a low dose (6.7×1013 vg per kilogram of body weight), and 12 received a high dose (2.0×1014 vg per kilogram). The primary outcome was safety. The secondary outcome was the time until death or the need for permanent ventilatory assistance. In exploratory analyses, we compared scores on the CHOP INTEND (Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders) scale of motor function (ranging from 0 to 64, with higher scores indicating better function) in the two cohorts and motor milestones in the high-dose cohort with scores in studies of the natural history of the disease (historical cohorts).Results: As of the data cutoff on August 7, 2017, all 15 patients were alive and event-free at 20 months of age, as compared with a rate of survival of 8% in a historical cohort. In the high-dose cohort, a rapid increase from baseline in the score on the CHOP INTEND scale followed gene delivery, with an increase of 9.8 points at 1 month and 15.4 points at 3 months, as compared with a decline in this score in a historical cohort. Of the 12 patients who had received the high dose, 11 sat unassisted, 9 rolled over, 11 fed orally and could speak, and 2 walked independently. Elevated serum aminotransferase levels occurred in 4 patients and were attenuated by prednisolone.Conclusions: In patients with SMA1, a single intravenous infusion of adeno-associated viral vector containing DNA coding for SMN resulted in longer survival, superior achievement of motor milestones, and better motor function than in historical cohorts. Further studies are necessary to confirm the safety and efficacy of this gene therapy. (Funded by AveXis and others; ClinicalTrials.gov number, NCT02122952 .). [ABSTRACT FROM AUTHOR]

BACKGROUND Patients with acute myeloid leukemia (AML) and a FLT3 mutation have poor outcomes. We conducted a phase 3 trial to determine whether the addition of midostaurin -- an oral multitargeted kinase inhibitor that is active in patients with a FLT3 mutation -- to standard chemotherapy would prolong overall survival in this population. METHODS We screened 3277 patients, 18 to 59 years of age, who had newly diagnosed AML for FLT3 mutations. Patients were randomly assigned to receive standard chemotherapy (induction therapy with daunorubicin and cytarabine and consolidation therapy with high-dose cytarabine) plus either midostaurin or placebo; those who were in remission after consolidation therapy entered a maintenance phase in which they received either midostaurin or placebo. Randomization was stratified according to subtype of FLT3 mutation: point mutation in the tyrosine kinase domain (TKD) or internal tandem duplication (ITD) mutation with either a high ratio (>0.7) or a low ratio (0.05 to 0.7) of mutant to wild-type alleles (ITD [high] and ITD [low], respectively). Allogeneic transplantation was allowed. The primary end point was overall survival. RESULTS A total of 717 patients underwent randomization; 360 were assigned to the midostaurin group, and 357 to the placebo group. The FLT3 subtype was ITD (high) in 214 patients, ITD (low) in 341 patients, and TKD in 162 patients. The treatment groups were well balanced with respect to age, race, FLT3 subtype, cytogenetic risk, and blood counts but not with respect to sex (51.7% in the midostaurin group vs. 59.4% in the placebo group were women, P = 0.04). Overall survival was significantly longer in the midostaurin group than in the placebo group (hazard ratio for death, 0.78; one-sided P = 0.009), as was event-free survival (hazard ratio for event or death, 0.78; one-sided P = 0.002). In both the primary analysis and an analysis in which data for patients who underwent transplantation were censored, the benefit of midostaurin was consistent across all FLT3 subtypes. The rate of severe adverse events was similar in the two groups. CONCLUSIONS The addition of the multitargeted kinase inhibitor midostaurin to standard chemotherapy significantly prolonged overall and event-free survival among patients with AML and a FLT3 mutation. [ABSTRACT FROM AUTHOR]

Peroxisome proliferator activated receptor gamma (PPARgamma) is a nuclear hormone receptor that has been shown to regulate differentiation and cell growth. Studies of the differentiative effects of PPARgamma agonists on several cancer cell lines led to the hypothesis that dysfunction of PPARgamma contributes to tumorigenesis. These functional observations were strengthened by genetic evidence: somatic loss-of-function mutations in PPARG, encoding PPARgamma, in sporadic colorectal carcinomas and somatic translocation of PAX8 and PPARG in follicular thyroid carcinoma. Recently overrepresentation of the H449H variant was found in a cohort of American patients with glioblastoma multiforme. The glioblastoma multiforme data suggest that PPARG contributes common, low-penetrance alleles for cancer susceptibility. To test this hypothesis in a broader range of cancers we examined a series of carcinomas of the cervix, endometrium, ovary, prostate, and kidney for germline sequence variation in PPARG. In addition to the two common sequence variants, P12A and H449H, there were five other sequence variants. P12A alleles were underrepresented in renal cell carcinoma patients compared to country-of-origin race-matched controls (3.75% vs. 12.1%, P<0.04). In contrast, the H449H variant was overrepresented in individuals with endometrial carcinoma compared to controls (14.4% vs. 6.25%, P<0.02). These observations lend genetic evidence consistent with our hypothesis that PPARG serves as a common, low-penetrance susceptibility gene for cancers of several types, especially those epidemiologically associated with obesity and fat intake.

Purpose: To prospectively compare cytogenetics and reverse transcriptase-polymerase chain reaction (RT-PCR) for detection of t(8;21)(q22;q22) and inv(16)(p13q22)/t(16;16)(p13;q22), aberrations characteristic of core-binding factor (CBF) acute myeloid leukemia (AML), in 284 adults newly diagnosed with primary AML., Patients and Methods: Cytogenetic analyses were performed at local laboratories, with results reviewed centrally. RT-PCR for AML1/ETO and CBFbeta/MYH11 was performed centrally., Results: CBF AML was ultimately identified in 48 patients: 21 had t(8;21) or its variant and AML1/ETO, and 27 had inv(16)/t(16;16), CBFbeta/MYH11, or both. Initial cytogenetic and RT-PCR analyses correctly classified 95.7% and 96.1% of patients, respectively (P =.83). Initial cytogenetic results were considered to be false-negative in three AML1/ETO-positive patients with unique variants of t(8;21), and in three CBFbeta/MYH11-positive patients with, respectively, an isolated +22; del(16)(q22),+22; and a normal karyotype. The latter three patients were later confirmed to have inv(16)/t(16;16) cytogenetically. Only one of 124 patients reported initially as cytogenetically normal was ultimately RT-PCR-positive. There was no false-positive cytogenetic result. Initial RT-PCR was falsely negative in two patients with inv(16) and falsely positive for AML1/ETO in two and for CBFbeta/MYH11 in another two patients. Two patients with del(16)(q22) were found to be CBFbeta/MYH11-negative. M4Eo marrow morphology was a good predictor of the presence of inv(16)/t(16;16)., Conclusion: Patients with t(8;21) or inv(16) can be successfully identified in prospective multi-institutional clinical trials. Both cytogenetics and RT-PCR detect most such patients, although each method has limitations. RT-PCR is required when the cytogenetic study fails; it is also required to determine whether patients with suspected variants of t(8;21), del(16)(q22), or +22 represent CBF AML. RT-PCR should not replace cytogenetics and should not be used as the only diagnostic test for detection of CBF AML because of the possibility of obtaining false-positive or false-negative results.

An insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme has previously been studied extensively in relationship to cardiovascular and renal disease. The deletion/deletion (D/D) genotype is associated with a poor outcome in immunoglobulin (Ig) A nephropathy. However, the association of this genetic marker in cardiovascular and renal disease has generated controversy, with the exception of the rate of progression and therapeutic responsiveness in IgA nephropathy. Many of the same cytokines and polypeptide mediators involved in fibrosis of the cardiovascular and renal systems have been shown to be involved in pulmonary fibrosis. We examined the I/D polymorphism of the angiotensin-converting enzyme in a group of 24 patents with interstitial pneumonia and moderate to severe pulmonary fibrosis defined by radiographic studies, pulmonary function tests, and histologic findings. The incidence of the D allele in this study population was 69.0%, which is approximately 15.0% higher than the incidence in the general population of 54.0%. The incidence of the D/D genotype was 42.0%, which is approximately 11.0% greater than that in the general population (31.0%). The distribution of the D/D, I/D, and insertion/insertion genotypes of these 24 patients was not significantly different from that of historical controls (P =.1; chi(2) test); there were marginally significantly more D alleles among the 48 observed alleles than would be expected (P =.04).

We have analyzed the survival motor neuron gene (SMN1) dosage in 100 parents of children with homozygous SMN1 deletions. Of these parents, 96 (96%) demonstrated the expected one-copy SMN1 carrier genotype. However, four parents (4%) were observed to have a normal two-copy SMN1 dosage. The presence of two intact SMN1 genes in the parent of an affected child indicates either the occurrence of a de novo mutation event or a situation in which one chromosome has two copies of SMN1, whereas the other is null. We have separated individual chromosomes from two of these parents with two-copy SMN1 dosage by somatic cell hybridization and have employed a modified quantitative dosage assay to provide direct evidence that one parent is a two-copy/ zero-copy SMN1 carrier, whereas the other parent had an affected child as the result of a de novo mutation. These findings are important for assessing the recurrence risk of parents of children with spinal muscular atrophy and for providing accurate family counseling.

PMS2 is one of a complex of genes encoding DNA repair proteins that includes MSH2, MLH1, MSH6 and MSH3. Mutation of any of these DNA mismatch repair genes leads to impairment of DNA repair and can lead to tumorigenesis. Germline mutation of PMS2 has been reported as a rare cause of hereditary nonpolyposis colorectal cancer (HNPCC) and Turcot's syndrome. The PMS2 gene is located on chromosome 7p22 and consists of 15 exons. Within exon 11 of PMS2 is a coding repeat of eight adenosines. This study reports on the finding of a nonexpressed pseudogene that is highly homologous to the PMS2 gene in this region. The pseudogene is polymorphic for two alterations in the repeat region: a 3 bp delAAA at a site corresponding to nucleotide 1231 in PMS2; and an AA-->GG change at nucleotide 1238. Due to the high homology in both intronic and exonic sequences, polymorphisms in this pseudogene could be mistaken for mutations in the PMS2 gene and erroneously thought to be a cause of HNPCC and/or Turcot's syndrome., (Copyright 2000 Wiley-Liss, Inc.)

Diffuse uterine leiomyomatosis is a rare condition distinguished from the common uterine leiomyomata by involvement of the entire myometrium by innumerable, ill-defined, often small and confluent, histologically benign smooth-muscle nodules. Fourteen cases have been previously described in the literature. We report a case of diffuse leiomyomatosis in a 39-year-old woman. Several microscopic foci of the process were microdissected for clonality analysis. All samples showed a non-random X-chromosome inactivation pattern, and thus were consistent with a monoclonal neoplastic population of cells. However, in different foci of tumor, different X chromosomes were inactivated, supporting the independent origin of neoplastic clones and rejecting the possibility of a single clonal origin of all tumor cells. The results of the molecular analysis suggest that diffuse uterine leiomyomatosis may be an exuberant example of diffuse and uniform involvement of the entire myometrium by multiple leiomyomata. HUM PATHOL 31:1429-1432., (Copyright 2000 by W.B. Saunders Company)

PPARgamma, the gamma isoform of a family of peroxisome proliferator activated receptors, plays a key role in adipocyte differentiation. Recently, its broad expression in multiple tissues and several epithelial cancers has been shown. Further, somatic loss of function mutations in PPARgamma have been found in primary colorectal carcinomas. We sought to determine if somatic high penetrance mutations in this gene might also play a role in glioblastoma multiforme (GBM). We also examined this gene to determine if common low penetrance polymorphic alleles might lend low level susceptibility to GBM in the general population. No somatic high penetrance mutations were detected in 96 sporadic GBMs. However, polymorphic alleles at codons 12 and 449 were significantly over-represented among the 27 unrelated American patients with sporadic GBM compared to 80 race matched controls. While nine (33%) were heterozygous for the P12A variant, c.34C/G (cytosine to guanine change at nucleotide 34), 12 (15%) controls were heterozygous for P12A (p<0.05). Similarly, 13 of 26 (50%) glioblastoma patients compared to 10 of 80 (12%) normal controls were found to have the heterozygous H449H polymorphism (p<0.001). The over-representation of H449H in glioblastoma patients was confirmed with a second validation set of American patients. When both American series were combined, polymorphic H449H was over-represented among cases versus controls (p<0.001) and there was a similar trend (p=0.07) for P12A. The precise mechanism for this association is unknown but these PPARgamma polymorphisms may be acting in a low penetrance predisposing manner. However, these associations were not found in a German population, possibly arguing that if these variants are in linkage disequilibrium with a third locus, then this effect is relatively new, after the settlement of the American colonies.

The role of genetic factors in the etiology of colorectal cancers (CRCs) has recently been elucidated with the discovery of the mismatch repair. These genes are responsible for less than 5% of all cases of CRCs in Caucasian series. In this pilot study, tumors from 5 randomly ascertained CRC patients were subjected to microsatellite analysis, and two were microsatellite unstable. Both of these two patients had germline mutations in MSH2. If this finding can be confirmed in a larger series of patients, it suggests that MMR genes play an important role in the etiology of CRCs in Africa.

Proximal spinal muscular atrophy (SMA) is a common motor neuron disease in humans and in its most severe form causes death by the age of 2 years. It is caused by defects in the telomeric survival motor neuron gene ( SMN1 ), but patients retain at least one copy of a highly homologous gene, centromeric SMN ( SMN2 ). Mice possess only one survival motor neuron gene ( Smn ) whose loss is embryonic lethal. Therefore, to obtain a mouse model of SMA we created transgenic mice that express human SMN2 and mated these onto the null Smn (-/-)background. We show that Smn (-/-); SMN2 mice carrying one or two copies of the transgene have normal numbers of motor neurons at birth, but vastly reduced numbers by postnatal day 5, and subsequently die. This closely resembles a severe type I SMA phenotype in humans and is the first report of an animal model of the disease. Eight copies of the transgene rescues this phenotype in the mice indicating that phenotypic severity can be modulated by SMN2 copy number. These results show that SMA is caused by insufficient SMN production by the SMN2 gene and that increased expression of the SMN2 gene may provide a strategy for treating SMA patients.

A single report of brothers born to first-cousin parents with a form of acute spinal muscular atrophy (SMA) and congenital fractures suggested that this combination represented a distinct form of autosomal recessive SMA. We describe a boy with hypotonia and congenital fractures whose sural nerve and muscle biopsies were consistent with a form of spinal muscular atrophy. Molecular studies identified no abnormality of the SMN(T) gene on chromosome 5. This case serves to validate the suggestion of a distinct and rare form of spinal muscular atrophy while not excluding possible X-linked inheritance., (Copyright 1999 Wiley-Liss, Inc.)

Instability in the repeat size of microsatellite sequences has been described in both hereditary nonpolyposis and sporadic colorectal cancers. Tumors expressing microsatellite instability are identified through the comparison of the repeat sizes at multiple microsatellite loci between tumor and matched normal tissue DNA. The use of a five-marker panel including two mononucleotide repeat microsatellites, BAT-25 and BAT-26, has recently been suggested for the clinical determination of tumor microsatellite instability. The BAT-25 and BAT-26 loci included in this panel have both demonstrated sensitivity to microsatellite instability and normal quasimonomorphic allelic patterns, which has simplified the distinction between normal and unstable alleles. However, in this study, we identified allelic variations in the size of the poly(A) tract at BAT-26 in 12.6% of 103 healthy African-Americans screened. In addition, 18.4% exhibited allelic size variations in the poly(T) tract at BAT-25. Finally, 2.9% showed variant alleles at both BAT-25 and BAT-26 loci. Screening a small population of Nigerians confirmed the polymorphic nature of both loci and the ethnic origin of alleles not identified in other populations studied thus far. Our results dispute the quasimonomorphic nature of both BAT-25 and BAT-26 in all populations and support the need for thorough population studies to define the different allelic profiles and frequencies at microsatellite loci.

Spinal muscular atrophy (SMA) is a recessive disorder characterized by loss of motor neurons in the spinal cord. It is caused by mutations in the telomeric survival motor neuron 1 ( SMN1 ) gene. Alterations within an almost identical copy gene, the centromeric survival motor neuron 2 ( SMN2 ) gene produce no known phenotypic effect. The exons of the two genes differ by just two nucleotides, neither of which alters the encoded amino acids. At the genomic level, only five nucleotides that differentiate the two genes from one another have been reported. The entire genomic sequence of the two genes has not been determined. Thus, differences which might explain why SMN1 is the SMA gene are not readily apparent. In this study, we have completely sequenced and compared genomic clones containing the SMN genes. The two genes show striking similarity, with the homology being unprecedented between two different yet functional genes. The only critical difference in an approximately 32 kb region between the two SMN genes is the C->T base change 6 bp inside exon 7. This alteration but not other variations in the SMN genes affects the splicing pattern of the genes. The majority of the transcript from the SMN1 locus is full length, whereas the majority of the transcript produced by the SMN2 locus lacks exon 7. We suggest that the exon 7 nucleotide change affects the activity of an exon splice enhancer. In SMA patients, the loss of SMN1 but the presence of SMN2 results in low levels of full-length SMN transcript and therefore low SMN protein levels which causes SMA.