Improved outcomes of large B-cell lymphoma patients treated with CD19 CAR T in the UK over time.

The success of CD19 Chimeric antigen receptor (CAR) T-cell therapy in large B-cell lymphoma (LBCL) has been partially offset by toxicity and logistical challenges, which off-the-shelf agents like CD20xCD3 bispecific antibodies might potentially overcome. However, when using CAR T outcomes as the 'standard-of-care comparator̕ for relapsed/refractory (r/r) LBCL, a potential learning curve with implementing a novel, complex therapy like CAR T needs to be considered. To address this, we analysed 726 UK patients intended to be treated with CD19 CAR T for r/r LBCL and compared outcomes between the first year of the national CAR T programme (Era 1; 2019) and the more recent treatment era (Era 2; 2020-2022). We identified significant improvements for Era 2 versus Era 1 in dropout rate (17% vs. 27%, p = 0.001), progression-free survival (1-year PFS 50% vs. 32%, p < 0.001) and overall survival (1-year OS 60% vs. 40%, p < 0.001). We also observed increased use of bridging therapy, improvement in bridging outcomes, more tocilizumab/corticosteroid use, reduced high-grade cytokine release syndrome (4% vs. 9%, p = 0.01) and intensive care unit admissions (20% vs. 32%, p = 0.001). Our results demonstrate significant improvement in CAR T outcomes over time, highlighting the importance of using up-to-date clinical data when comparing CAR T against new treatment options for r/r LBCL.

Self-reported gastrointestinal disorders among veterans with gulf war illness with and without posttraumatic stress disorder.

BACKGROUND: Gulf War Illness (GWI) is a chronic, multi-symptom disorder affecting 25%-32% of Gulf War veterans. Veterans with GWI disproportionately suffer from gastrointestinal (GI) disorders. Given the increasing evidence supporting a gut-brain axis, we explore the relationship between post-traumatic stress disorder (PTSD), GWI, and self-reported GI disorders among GW veterans. METHODS: Veterans from the Gulf War Era Cohort and Biorepository responded to a mail-based survey (N = 1058). They were stratified by GWI (Centers for Disease Control definition) and PTSD status. This yielded three groups: GWI-, GWI+/PTSD-, and GWI+/PTSD+. Multivariable logistic regression adjusting for demographic and military characteristics examined associations between GWI/PTSD groups and GI disorders. Results were expressed as adjusted odds ratios (aOR) with 95% confidence intervals (95% CI). KEY RESULTS: The most frequently reported GI disorders were irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD), and colon polyps (CP). The GWI+/PTSD+ group had a higher odds of these disorders than the GWI+/PTSD- group (aORIBS  = 3.12, 95% CI: 1.93-5.05; aORGERD  = 2.04, 95% CI: 1.44-2.90; aORCP  = 1.85, 95% CI: 1.23-2.80), which had a higher odds of these disorders than the GWI- group (aORIBS  = 4.38, 95% CI: 1.55-12.36; aORGERD  = 2.51 95% CI: 1.63-3.87; aORCP  = 2.57, 95% CI: 1.53-4.32). CONCLUSIONS & INFERENCES: GW veterans with GWI and PTSD have significantly higher odds of specific self-reported GI disorders than the other groups. Given the known bidirectional influences of the gut and brain, these veterans may benefit from a holistic healthcare approach that considers biopsychosocial contributors to the assessment and management of disease.

An awareness and prevalence study of Irish cold-water athletes and external auditory canal exostoses.

OBJECTIVE: This study aimed to determine the awareness, otological symptoms and prevalence of external auditory canal exostoses in Irish cold-water athletes. METHOD: An online and in person cross-sectional survey was undertaken with Irish cold-water athletes to explore athletes' awareness, known prevalence of external auditory canal exostoses and attitudes towards preventive measures. RESULTS: Of the 926 participants surveyed, 67.5 per cent were aware of external auditory canal exostoses. Triathletes reported the lowest awareness (39.9 per cent) among water athletes. A total of 9.7 per cent (n = 90) had previously been diagnosed with external auditory canal exostoses and 46.7 per cent (n = 42) were non-surfers. Ear symptoms were reported in 76 per cent of athletes. Otoscopic examinations showed that 23.7 per cent had external auditory canal exostoses, 3.6 per cent of whom were aware of their diagnosis. CONCLUSION: The majority of Irish surfing athletes are aware of external auditory canal exostoses. There is less awareness with regard to Ireland's newly emerging sports such as open water swimming and triathlons. Over 90 per cent of athletes surveyed had no idea they had external auditory canal exostoses, which highlights the need to increase public awareness.

Development of an auxotrophic, live-attenuated Brucella suis vaccine strain capable of expressing multimeric GnRH.

Feral swine cost around $1.5 billion each year in agricultural, environmental, and personal property damages. They are also the most widespread carriers of the zoonotic disease brucellosis, which threatens both livestock bio-security and public health. Currently, there is no approved vaccine against brucellosis in pigs. This is a preliminary report on the development of a live-attenuated B. suis vaccine that could be employed to deliver heterologous antigens to control swine populations. An attenuated vaccine strain provided significant protection against B. suis challenge in mice. Leucine auxotrophy in the vaccine strain allowed the over-expression of heterologous antigens without the use of antibiotic resistant markers. Vaccinated mice showed the development of antibodies against expressed antigen. Further evaluation is required to assess its ability to cause infertility using the mouse model prior to further testing for use as a tool for feral swine population and disease control.

Donor-Derived Metastatic Melanoma and Checkpoint Inhibition.

Donor-derived malignancy, particularly melanoma, is a rare but known complication of organ transplantation. Here we describe a case of metastatic melanoma in a deceased-donor kidney transplant recipient. After diagnosis, the patient was successfully treated with cessation of immunosuppression, explantation of the renal allograft, and novel melanoma therapies, including the mutation-targeted agents dabrafenib and trametinib and the immune checkpoint inhibitor nivolumab. These 2 new classes of melanoma therapy have revolutionized the course of metastatic melanoma, altering it from one of nearly certain mortality to one of potential cure. This case reviews the mechanisms of action of these therapies and reports our experience with them in the rare setting of donor-derived melanoma in a dialysis-dependent patient.

A pilot study using preoperative cerebral tissue oxygen saturation to stratify cardiovascular risk in major non-cardiac surgery.

This prospective pilot study evaluated whether low preoperative cerebral tissue oxygen saturation is associated with unfavourable outcomes after major elective non-cardiac surgery. Eighty-one patients over 60 years of age, American Society of Anesthesiologists physical status 3 or 4, were recruited. Resting cerebral tissue oxygen saturation was recorded on room air, and after oxygen supplementation, using cerebral oximetry. The primary outcome was 30-day major adverse event of combined mortality or severe morbidity, and the secondary outcome was 30-day new disability. Eleven patients (13.6%) suffered a major adverse event, and 28 patients (34.6%) experienced new disability. Room air cerebral tissue oxygen saturation was significantly different between patients who had a major adverse event, 67% (95% confidence interval [CI] 65-70) versus unaffected, 71% (95% CI 70-72; P=0.04). No statistical difference was found between patients for new disability (range 70%-74%; P=0.73). Room air cerebral tissue oxygen saturation was significantly associated with major adverse events (odds ratio 1.36 (95% CI 1.03-1.79), P=0.03). Saturation levels ≤68% carried a positive likelihood ratio of 2.2 for death or severe morbidity, P=0.04. A definitive trial is required to confirm if cerebral oximetry can be used to stratify the cardiovascular risk of patients presenting for non-cardiac surgery.

The chemokine receptor CCR7 promotes mammary tumorigenesis through amplification of stem-like cells.

The chemokine receptor CCR7 is widely implicated in breast cancer pathobiology. Although recent reports correlated high CCR7 levels with more advanced tumor grade and poor prognosis, limited in vivo data are available regarding its specific function in mammary gland neoplasia and the underlying mechanisms involved. To address these questions we generated a bigenic mouse model of breast cancer combined with CCR7 deletion, which revealed that CCR7 ablation results in a considerable delay in tumor onset as well as significantly reduced tumor burden. Importantly, CCR7 was found to exert its function by regulating mammary cancer stem-like cells in both murine and human tumors. In vivo experiments showed that loss of CCR7 activity either through deletion or pharmacological antagonism significantly decreased functional pools of stem-like cells in mouse primary mammary tumors, providing a mechanistic explanation for the tumor-promoting role of this chemokine receptor. These data characterize the oncogenic properties of CCR7 in mammary epithelial neoplasia and point to a new route for therapeutic intervention to target evasive cancer stem cells.

PRC2-independent chromatin compaction and transcriptional repression in cancer.

The silencing of large chromosomal regions by epigenetic mechanisms has been reported to occur frequently in cancer. Epigenetic marks, such as histone methylation and acetylation, are altered at these loci. However, the mechanisms of formation of such aberrant gene clusters remain largely unknown. Here, we show that, in cancer cells, the epigenetic remodeling of chromatin into hypoacetylated domains covered with histone H3K27 trimethylation is paralleled by changes in higher-order chromatin structures. Using fluorescence in situ hybridization, we demonstrate that regional epigenetic silencing corresponds to the establishment of compact chromatin domains. We show that gene repression is tightly correlated to the state of chromatin compaction and not to the levels of H3K27me3-its removal through the knockdown of EZH2 does not induce significant gene expression nor chromatin decompaction. Moreover, transcription can occur with intact high-H3K27me3 levels; treatment with histone deacetylase inhibitors can relieve chromatin compaction and gene repression, without altering H3K27me3 levels. Our findings imply that compaction and subsequent repression of large chromatin domains are not direct consequences of PRC2 deregulation in cancer cells. By challenging the role of EZH2 in aberrant gene silencing in cancer, these findings have therapeutical implications, notably for the choice of epigenetic drugs for tumors with multiple regional epigenetic alterations.

A study of genotyping for management of human papillomavirus-positive, cytology-negative cervical screening results.

The effective management of women with human papillomavirus (HPV)-positive, cytology-negative results is critical to the introduction of HPV testing into cervical screening. HPV typing has been recommended for colposcopy triage, but it is not clear which combinations of high-risk HPV types provide clinically useful information. This study included 18,810 women with Hybrid Capture 2 (HC2)-positive, cytology-negative results and who were age ≥30 years from Kaiser Permanente Northern California. The median follow-up was 475 days (interquartile range [IQR], 0 to 1,077 days; maximum, 2,217 days). The baseline specimens from 482 cases of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) and 3,517 random HC2-positive noncases were genotyped using 2 PCR-based methods. Using the case-control sampling fractions, the 3-year cumulative risks of CIN3+ were calculated for each individual high-risk HPV type. The 3-year cumulative risk of CIN3+ among all women with HC2-positive, cytology-negative results was 4.6%. HPV16 status conferred the greatest type-specific risk stratification; women with HC2-positive/HPV16-positive results had a 10.6% risk of CIN3+, while women with HC-2 positive/HPV16-negative results had a much lower risk of 2.4%. The next most informative HPV types and their risks in HPV-positive women were HPV33 (5.9%) and HPV18 (5.9%). With regard to the etiologic fraction, 20 of 71 cases of cervical adenocarcinoma in situ (AIS) and adenocarcinoma in the cohort were positive for HPV18. HPV16 genotyping provides risk stratification useful for guiding clinical management; the risk among HPV16-positive women clearly exceeds the U.S. consensus risk threshold for immediate colposcopy referral. HPV18 is of particular interest because of its association with difficult-to-detect glandular lesions. There is a less clear clinical value of distinguishing the other high-risk HPV types.

Unsuspected pulmonary emboli adversely impact survival in patients with cancer undergoing routine staging multi-row detector computed tomography scanning.

BACKGROUND: While symptomatic venous thromboembolism adversely impacts survival among cancer patients, the outcome of cancer patients with unsuspected pulmonary embolism (UPE) found on routine cancer staging multi-row detector computed tomography (MDCT) scans is unknown. OBJECTIVE: To determine whether UPE detected on routine staging MDCT scans impacts overall survival among cancer patients. PATIENTS AND METHODS: We performed a matched cohort study of cancer patients diagnosed with UPE on routine staging scans between May 2003 and August 2006. Two controls (n = 137) were individually matched by age (± 5 years), cancer type and stage for each UPE patient (n = 70). We used Cox's proportional hazard models to compare the mortality between UPE patients and their matched controls. RESULTS: The hazard ratio (HR) for death among UPE patients was 1.51 (95% CI 1.01-2.27, P = 0.048). Compared with their matched controls, patients with UPE more proximal than the subsegmental arterial branches had a HR for death at 6 months of 2.28 (95% CI 1.20-4.33, P = 0.011) and an overall HR of 1.70 (95% CI 1.06-2.74, P = 0.027). Survival among UPE patients with isolated subsegmental PE (ISSPE) was not significantly different than that of matched controls (HR 1.04 95% CI 0.44-2.39, P = 0.92). CONCLUSIONS: UPE identified more proximal than the subsegmental arterial branches has a significant negative impact on survival among cancer patients.

Positive affect is associated with cardiovascular reactivity, norepinephrine level, and morning rise in salivary cortisol.

Positive affect was examined as a predictor of (1) cardiovascular reactivity during a sadness and an anger recall task and recovery following the protocol, (2) epinephrine (EPI) and norepinephrine (NOREPI) reactivity and level during the recall protocol, and (3) the diurnal pattern of salivary cortisol. Sample was 328 individuals. Negative affect, age, race, sex, smoking status, income, and BMI were adjusted. During sadness recall, positive affect was inversely related to systolic blood pressure (p=.007) and diastolic blood pressure (p=.049) reactivity, and unrelated to heart rate (p=.226). Positive affect was unrelated to reactivity during anger recall (ps>.19), and was unrelated to recovery at the end of the recall protocol. Positive affect was inversely related to the mean level of NOREPI (p=.046), and unrelated to EPI (p=.149). Positive affect was inversely related to the increase in cortisol 30 min post awakening (p=.042), and unrelated to the evening decline in cortisol levels (p=.174). Positive emotions may be relevant to good health.

IQ in late adolescence/early adulthood, risk factors in middle age and later all-cause mortality in men: the Vietnam Experience Study.

OBJECTIVE: To examine the role of potential mediating factors in explaining the IQ-mortality relation. DESIGN, SETTING AND PARTICIPANTS: A total of 4316 male former Vietnam-era US army personnel with IQ test results at entry into the service in late adolescence/early adulthood in the 1960/1970s (mean age at entry 20.4 years) participated in a telephone survey and medical examination in middle age (mean age 38.3 years) in 1985-6. They were then followed up for mortality experience for 15 years. MAIN RESULTS: In age-adjusted analyses, higher IQ scores were associated with reduced rates of total mortality (hazard ratio (HR)(per SD increase in IQ) 0.71; 95% CI 0.63 to 0.81). This relation did not appear to be heavily confounded by early socioeconomic position or ethnicity. The impact of adjusting for some potentially mediating risk indices measured in middle age on the IQ-mortality relation (marital status, alcohol consumption, systolic and diastolic blood pressure, pulse rate, blood glucose, body mass index, psychiatric and somatic illness at medical examination) was negligible (<10% attenuation in risk). Controlling for others (cigarette smoking, lung function) had a modest impact (10-17%). Education (0.79; 0.69 to 0.92), occupational prestige (0.77; 0.68 to 0.88) and income (0.86; 0.75 to 0.98) yielded the greatest attenuation in the IQ-mortality gradient (21-52%); after their collective adjustment, the IQ-mortality link was effectively eliminated (0.92; 0.79 to 1.07). CONCLUSIONS: In this cohort, socioeconomic position in middle age might lie on the pathway linking earlier IQ with later mortality risk but might also partly act as a surrogate for cognitive ability.

Vaccination with gamma-irradiated Neospora caninum tachyzoites protects mice against acute challenge with N. caninum.

Neospora caninum, an apicomplexan parasite, is a leading cause of bovine abortions worldwide. The efficacy of gamma-irradiated N. caninum strain NC-1 tachyzoites as a vaccine for neosporosis was assessed in C57BL6 mice. A dose of 528 Gy of gamma irradiation was sufficient to arrest replication but not host cell penetration by tachyzoites. Female C57BL6 mice were vaccinated with two intraperitoneal inoculations of 1 x 10(6) irradiated tachyzoites at 4-wk intervals. When stimulated with N. caninum tachyzoite lysates, splenocytes of vaccinated mice, cultured 5 and 10 wk after vaccination, secreted significant (P<0.05) levels of interferon gamma, interleukin (IL)-10, and small amounts of IL-4. Antibody isotype-specific ELISA of sera from vaccinated mice exhibited both IgG1 and IgG2a isotypes of antibodies. Vaccinated mice were challenged intraperitoneally with 2 x 10(7)N. caninum tachyzoites. All vaccinated mice remained healthy and showed no obvious signs of neosporosis up to the 25th day post-challenge when the study was terminated. All unvaccinated control mice died within 1 wk of infection. Gamma-irradiated N. caninum tachyzoites can serve as an effective, attenuated vaccine for N. caninum.

Eosinophilic angiocentric fibrosis as a cause of nasal obstruction.

We present the tenth case of Eosinophilic Angiocentric Fibrosis (EAF) in the english literature, which presented as nasal obstruction in a patient of Indian descent. The histopathological and clinical features of this underreported condition is discussed as well as other lesions that may show similar features to EAF.

Late results of selective axillary surgery based on contact cytology in women with operable breast cancer.

BACKGROUND: Interest in the possibility of intraoperative analysis of sentinel lymph nodes to select patients with operable breast cancer for immediate axillary clearance encouraged this review of a long-term experience of selective axillary surgery based on intraoperative contact cytology of conventionally sampled nodes. Survival was assessed as a potential marker for understaging. METHODS: Records of 437 patients who had surgery between 1991 and 1994 were reviewed to compare rates of axillary recurrence in patients who had contact cytology only with those who had contact cytology and axillary clearance. RESULTS: Axillary recurrence occurred in seven (3 per cent) of 219 patients who had negative contact cytology, three (4 per cent) of 75 patients who had positive contact cytology with axillary clearance and one (1 per cent) of 93 who had axillary clearance alone. In patients with positive contact cytology, 131 (78 per cent) of 168 positive nodes were in the sample specimen, which included all positive nodes on 19 occasions. Survival probability at 36, 72 and 96 months was 92, 87 and 84 per cent respectively for patients with negative contact cytology, and 85, 73 and 71 per cent for patients with positive cytology and axillary clearance. CONCLUSION: A selective approach to axillary surgery based on intraoperative contact cytology of sampled lymph nodes gave good long-term control of axillary disease.

Absorption and DNA protective effects of flavonoid glycosides from an onion meal.

BACKGROUND: It is widely believed that antioxidant micronutrients obtained from fruit and vegetables afford significant protection against cancer and heart disease, as well as ageing. Flavonoids are potential antioxidants found in foods such as onions; information on their effectiveness in vivo is so far lacking. AIMS: To determine uptake as well as in vivo antioxidant effects of flavonoids from foods. METHODS: Six healthy non-obese normocholesterolaemic female volunteers in the age range 20-44 years participated in a randomised two-phase crossover supplementation trial to compare the antioxidant effects associated with (a) a meal of fried onions and (b) a meal of fried onions and fresh cherry tomatoes. Plasma flavonoids, lymphocyte DNA damage, plasma ascorbic acid, tocopherols and carotenoids, urinary malondialdehyde and 8-hydroxy-2'-deoxyguanosine were determined to assess flavonoid absorption and antioxidant efficacy. RESULTS: Flavonoid glucosides (quercetin-3-glucoside and isorhamnetin-4-glucoside) were significantly elevated in plasma following ingestion of the onion meal and the increases were associated with an increased resistance of lymphocyte DNA to DNA strand breakage. A significant decrease in the level of urinary 8-hydroxy-2'-deoxyguanosine was evident at 4 h following ingestion of the onion meal. After the combined tomato and onion meal, only quercetin was detected in plasma. Endogenous base oxidation was decreased but resistance to strand breakage was unchanged. There was no significant change in the excretion of urinary malondialdehyde following either meal. CONCLUSION: Both meals--onions, and onions together with tomatoes--led to transient decreases in biomarkers of oxidative stress, although the particular biomarkers affected differ. It is possible that the differences in patterns of response reflect the different uptakes of flavonoids but the underlying mechanism is not understood.

Bioavailability and efficiency of rutin as an antioxidant: a human supplementation study.

OBJECTIVE: To determine the potential antioxidant effect of rutin (quercetin-3-O-beta-rutinoside) supplementation. DESIGN: A 6-week randomized single-blind placebo controlled trial was conducted; 500 mg rutin supplement was compared to an equivalent amount of glucose placebo. In addition, a pharmacokinetic study was carried out. SETTING: The Rowett Research Institute, Aberdeen, UK. SUBJECTS: Eighteen healthy non-obese normocholesterolaemic female volunteers in the age range 18-48 y. MAIN OUTCOME MEASURES: Plasma flavonoids, ascorbic acid, tocopherols and carotenoids, plasma antioxidant capacity, lymphocyte DNA damage, blood chemistry and haematology, liver function tests, urinary malondialdehyde, 8-hydroxy-2-deoxyguanosine and 8-iso-prostaglandin F2alpha. RESULTS: Eighteen volunteers completed the trial. Rutin supplementation did not induce any adverse changes in blood chemistry or indices of liver function. Plasma flavonoids were significantly elevated in the rutin-supplemented group. Endogenous oxidation of pyrimidines was significantly decreased in both rutin- and placebo-treated volunteers. There was no significant change in the level of urinary 8-hydroxy-2'-deoxyguanosine or urinary malondialdehyde in either group. A linear correlation was observed between urinary malondialdehyde and urinary 8-iso-prostaglandin F2alpha (R = 0.54, P<0.01). CONCLUSION: Six weeks' rutin supplementation significantly elevated the levels of three plasma flavonoids (quercetin. kaempferol and isorhamnetin) but there was no significant change in plasma antioxidant status. The decrease in the level of endogenous base oxidation in lymphocyte DNA seen in both the placebo- and rutin-supplemented subjects may reflect seasonal changes in other dietary antioxidants.

Gender-specific metabolism of benz[a]anthracene in hepatic microsomes from Long-Evans and Hooded Lister rats.

The cytochrome P450 isoforms responsible for the regio-selective metabolism of benz[a]anthracene (BA) are poorly defined but as with other polycyclic aromatic hydrocarbons (PAHs) may include members of the CYP2C sub-family. Since the expression of some of these is regulated in a gender-specific manner and may be altered by age, rat strain or by phenobarbital treatment, the effects of these variables on metabolism of BA to diols was investigated. These studies used hepatic, microsomal membranes from immature and adult Long-Evans rats and adult Hooded Lister rats. BA-diols were resolved by normal phase HPLC into three discrete peaks identified as benz[a]anthracene-5,6-diol (BA-5,6-diol), benz[a]anthracene-10, 11-diol (BA-10,11-diol) and a mixture of benz[a]anthracene-3,4- and -8,9-diols (BA-3,4-diol and BA-8,9-diol and termed Peak(3/8)). Significant gender-related differences were found in the rates of diol formation in adults of both the Long-Evans and Hooded Lister rat strains. Formation of BA-10,11-diol and to a lesser extent the components of Peak(3/8) were greater in the male compared to female animals by factors of at least 14 and two, respectively. An age-dependent effect is also observed in the Long-Evans rat since these differences are still apparent in prepubertal animals but to a lesser extent (gender ratio male:female BA-10,11-diol 9X; Peak(3/8) 1.4X). In contrast BA-5,6-diol was formed at similar rates by membranes from female and male rats whether mature (Long-Evans and Hooded Lister) or immature (Long-Evans). Phenobarbital treatment of the adult Long-Evans rats resulted in a moderate increase in the formation of each diol other than at the 10,11-position and the induction was not gender specific. The rate of formation of BA-10, 11-diol was decreased in phenobarbital-treated male rats suggesting modulation of a male specific isoform. Measurement of microsomal epoxide hydrolase revealed no gender or age differences and suggests that this enzyme is not rate limiting in BA-diol formation and thus is not responsible for the differences in BA-diol formation observed. The results suggest that CYP2C11 along with a male-specific isoenzyme not regulated by age are important in the formation of BA-10,11-diol and a component(s) of Peak(3/8) in males. CYPs 2B2 and/or 2C6 appear to be involved in formation of BA-5,6-diol in male and female. Identification of the CYPs involved in the regio-selective metabolism of BA may lead to an explanation of the lower carcinogenic potency of this PAH compared to dimethylbenz[a]anthracene and this study provides novel clues concerning the identities of the CYPs, which are important.

Molecular analysis of phyllodes tumors reveals distinct changes in the epithelial and stromal components.

Phyllodes tumors are fibroepithelial mammary lesions that tend to behave in a benign fashion but may undergo sarcomatous transformation. A study of clonality in these tumors has suggested that the epithelial component is polyclonal, but the stroma is monoclonal, and thus forms the neoplastic component of the lesion. In this study microsatellites on chromosome 1q and chromosome 3p were assessed for allelic imbalance (AI) in 47 phyllodes tumors; in all cases stroma and epithelium were analyzed separately. Ten of 42 (24%) phyllodes tumors showed AI at one or more markers on 3p, and 14 of 46 (30%) showed AI on chromosome 1. Five tumors had changes in both the epithelium and stroma. Eight tumors had changes only detectable in the stroma and eight, changes in the epithelium only. Three tumors exhibited low-level microsatellite instability in the epithelium but not in the stroma. The results show that AI on 3p and 1q does occur in phyllodes tumors and that it can occur in both the stroma and epithelium, sometimes as independent genetic events. These unexpected findings throw into doubt the classical view that phyllodes tumors are simply stromal neoplasms and raise questions about the nature of stromal and epithelial interactions in these tumors.

Juxta-centromeric region of human chromosome 21 is enriched for pseudogenes and gene fragments.

A physical map including four pseudogenes and 10 gene fragments and spanning 500 kb in the juxta-centromeric region of the long arm of human chromosome 21 is presented. cDNA fragments isolated from a selected cDNA library were characterized and mapped to the 831B6 YAC and to two BAC contigs that cover 250 kb of the region. An 85 kb genomic sequence located in the proximal region of the map was analyzed for putative exons. Four pseudogenes were found, including psiIGSF3, psiEIF3, psiGCT-rel whose functional copies map to chromosome 1p13, chromosome 2 and chromosome 22q11, respectively. The TTLL1 pseudogene corresponds to a new gene whose functional copy maps to chromosome 22q13. Ten gene fragments represent novel sequences that have related sequences on different human chromosomes and show 97-100% nucleotide identity to chromosome 21. These may correspond to pseudogenes on chromosome 21 and to functional genes in other chromosomes. The 85 kb genomic sequence was analyzed also for GC content, CpG islands, and repetitive sequence distribution. A GC-poor L isochore spanning 40 kb from satellite 1 was observed in the most centromeric region, next to a GC-rich H isochore that is a candidate region for the presence of functional genes. The pericentric duplication of a 7.8 kb region that is derived from the 22q13 chromosome band is described. We showed that the juxta-centromeric region of human chromosome 21 is enriched for retrotransposed pseudogenes and gene fragments transferred by interchromosome duplications, but we do not rule out the possibility that the region harbors functional genes also.