Drug monitoring during ciprofloxacin prophylaxis of allogeneic stem cell transplant patients: associations with bacterial infections through a monocentric observational prospective study

BACKGROUND

Bacterial infection ranks amongst the most common causes of morbidity and mortality in patients undergoing allogeneic haematopoietic stem cell transplantation (alloHSCT). Although ciprofloxacin (CIP) prophylaxis is recommended, information on serum levels and clinical course is lacking.

AIM

To investigate relationships between CIP level and failure of prophylaxis, particularly in terms of whether different pharmacokinetic (PK) indices [area under the concentration-time curve (AUC0-24h) vs single time samples] correlate differently with the outcome.

METHODS

This prospective observational monocentric study was conducted at a 1500-bed teaching hospital (March 2018-March 2019), including 63 adult patients with alloHSCT receiving CIP prophylaxis. Blood samples were drawn at three sampling times (1, 6 and 12 h post-administration), twice per week, and measured via high performance liquid chromatography. The onset of febrile episodes (FEBs) indicated suspected failure of CIP prophylaxis. Positive blood cultures [bloodstream infection (BSI)] indicated confirmed failure of prophylaxis.

FINDINGS

Seven of 63 patients died without significant differences in their average CIP levels compared with survivors, with patients experiencing FEBs (54/63) displaying a 13% [95% confidence interval (CI) 4-22%] lower probability of survival. In total, 225 sets of three values (triplets) were obtained from 58 primary CIP episodes. Triplets preceding BSI with Gram-negative bacteria (GNB-BSI) showed lower AUC0-24h on average, but similar single time sample indices. An AUC0-24h of ≤21.61 mgh/L resulted in four-fold higher odds of GNB-BSI (adjusted odds ratio 3.96, 95% CI 1.21-13.00). These results were independent of the administration route, patient demographics or sampling protocol deviations, indicating reduced CIP exposure upon GNB-BSI events.

CONCLUSION

Monitoring CIP levels, using multiple sampling times, may be useful to reduce alloHSCT-associated bacterial infections. Further analysis is needed to investigate causality.

Randomized phase-III study of low-dose cytarabine and etoposide + /- all-trans retinoic acid in older unfit patients with NPM1-mutated acute myeloid leukemia

The aim of this randomized clinical trial was to evaluate the impact of all-trans retinoic acid (ATRA) in combination with non-intensive chemotherapy in older unfit patients (> 60 years) with newly diagnosed NPM1-mutated acute myeloid leukemia. Patients were randomized (1:1) to low-dose chemotherapy with or without open-label ATRA 45 mg/m2, days 8-28; the dose of ATRA was reduced to 45 mg/m2, days 8-10 and 15 mg/m2, days 11-28 after 75 patients due to toxicity. Up to 6 cycles of cytarabine 20 mg/day s.c., bid, days 1-7 and etoposide 100 mg/day, p.o. or i.v., days 1-3 with (ATRA) or without ATRA (CONTROL) were intended. The primary endpoint was overall survival (OS). Between May 2011 and September 2016, 144 patients (median age, 77 years; range, 64-92 years) were randomized (72, CONTROL; 72, ATRA). Baseline characteristics were balanced between the two study arms. The median number of treatment cycles was 2 in ATRA and 2.5 in CONTROL. OS was significantly shorter in the ATRA compared to the CONTROL arm (p = 0.023; median OS: 5 months versus 9.2 months, 2-years OS rate: 7% versus 10%, respectively). Rates of CR/CRi were not different between treatment arms; infections were more common in ATRA beyond treatment cycle one. The addition of ATRA to low-dose cytarabine plus etoposide in an older, unfit patient population was not beneficial, but rather led to an inferior outcome.The clinical trial is registered at clinicaltrialsregister.eu (EudraCT Number: 2010-023409-37, first posted 14/12/2010).

[Hypernatremia and polyuria in a female patient with an initial diagnosis of secondary acute myeloid leukemia]

A 66-year-old female patient with the initial diagnosis of acute myeloid leukemia is reported. Paraneoplastic syndrome manifested as hypernatremia due to central diabetes insipidus (CDI), which could be controlled with the administration of desmopressin. After initiation of the induction therapy, the required desmopressin administration could be reduced and terminated. In the further course, the early increasing polyuria and hypernatremia indicated the primary refractory acute myeloid leukemia.

Elderly Anticoagulated Patient in General Dental Practice Case Reports from everyday Life

The anticoagulated elderly patient represents a major and sometimes dreaded challenge for the dentist on a daily basis, as postoperative bleeding can lead to serious problems, especially during dental surgical procedures. Knowledge of the various anticoagulants with regard to type, mode of action and influences on dental surgical procedures is indispensable for the dentist. Using case studies from the everyday life of a dental practice in a small town in Thuringia, this problem will be examined in more detail.

Randomized phase-II trial evaluating induction therapy with idarubicin and etoposide plus sequential or concurrent azacitidine and maintenance therapy with azacitidine

The aim of this randomized phase-II study was to evaluate the effect of substituting cytarabine by azacitidine in intensive induction therapy of patients with acute myeloid leukemia (AML). Patients were randomized to four induction schedules for two cycles: STANDARD (idarubicin, cytarabine, etoposide); and azacitidine given prior (PRIOR), concurrently (CONCURRENT), or after (AFTER) therapy with idarubicin and etoposide. Consolidation therapy consisted of allogeneic hematopoietic-cell transplantation or three courses of high-dose cytarabine followed by 2-year maintenance therapy with azacitidine in the azacitidine-arms. AML with CBFB-MYH11, RUNX1-RUNX1T1, mutated NPM1, and FLT3-ITD were excluded and accrued to genotype-specific trials. The primary end point was response to induction therapy. The statistical design was based on an optimal two-stage design applied for each arm separately. During the first stage, 104 patients (median age 62.6, range 18-82 years) were randomized; the study arms PRIOR and CONCURRENT were terminated early due to inefficacy. After randomization of 268 patients, all azacitidine-containing arms showed inferior response rates compared to STANDARD. Event-free and overall survival were significantly inferior in the azacitidine-containing arms compared to the standard arm (p < 0.001 and p = 0.03, respectively). The data from this trial do not support the substitution of cytarabine by azacitidine in intensive induction therapy.

Epidemiological, genetic, and clinical characterization by age of newly diagnosed acute myeloid leukemia based on an academic population-based registry study (AMLSG BiO)

We describe genetic and clinical characteristics of acute myeloid leukemia (AML) patients according to age from an academic population-based registry. Adult patients with newly diagnosed AML at 63 centers in Germany and Austria were followed within the AMLSG BiO registry (NCT01252485). Between January 1, 2012, and December 31, 2014, data of 3525 patients with AML (45% women) were collected. The median age was 65 years (range 18-94). The comparison of age-specific AML incidence rates with epidemiological cancer registries revealed excellent coverage in patients < 70 years old and good coverage up to the age of 80. The distribution according to the European LeukemiaNet (ELN) risk categorization from 2010 was 20% favorable, 31% intermediate-1, 28% intermediate-2, and 21% adverse. With increasing age, the relative but not the absolute prevalence of patients with ELN favorable and intermediate-1 risk (p < 0.001), with activating FLT3 mutations (p < 0.001), with ECOG performance status < 2 (p < 0.001), and with HCT-CI comorbidity index < 3 (p < 0.001) decreased. Regarding treatment, obesity and favorable risk were associated with an intensive treatment, whereas adverse risk, higher age, and comorbidity index > 0 were associated with non-intensive treatment or best supportive care. The AMLSG BiO registry provides reliable population-based distributions of genetic, clinical, and treatment characteristics according to age.

Abstract P3-06-11: Understanding resistance mechanisms of PIK3a inhibition in breast cancer

Breast cancer is the most common non-cutaneous cancer in women worldwide. PIK3CA is the most frequently mutated oncogene in all invasive breast cancers, with about one third of cases harboring activating mutations. Small molecule therapeutics targeting PI3K pathway has been developed and investigated for a decade. Everolimus (an mTOR inhibitor) is now successfully used in conjunction with hormonal therapy in patients with metastatic hormone-receptor positive breast cancers. Inhibitors of PI3Kα have shown promise as a single agent as well as in combination with hormonal therapies. The high rate of primary and acquired resistance; however, limits clinical usage of this class of drugs. There is an urgent need to understand the resistance mechanisms of PI3K inhibition and develop strategies to overcome the resistance in breast cancer. We took a genome-scale functional screening approach to identify resistance mechanisms to PI3K inhibition in breast cancer. We performed a whole-genome lentiviral open-reading frame (ORF) overexpression screen in a breast cancer cell line (T47D) in the presence of a PI3Kα inhibitor. We screened a total of 15,590 ORFs and identified 75 genes whose overexpression confers resistance to PI3K inhibition. Once we validate the hits, we plan to determine the mechanisms by which the genes confer resistance. We also plan to perform RNA-sequencing in patient samples with PI3Ka resistance to evaluate the clinical relevance of these genes and pathways.

Citation Format: Le X, Luo F, Treacy D, Wulf G, Garraway L. Understanding resistance mechanisms of PIK3a inhibition in breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-06-11.

Abstract OT1-4-02: Phase I study of the combination of BKM120 and olaparib for the treatment of high grade serous ovarian cancer (HGSC) and triple negative breast cancer (TNBC)

Background: In vivo synergy of the PI3-kinase inhibitor BKM120 with the PARP inhibitor olaparib has been observed using a mouse model of BRCA1-related breast cancer and sporadic TNBC (Juvekar et al and Ibrahim et al, Cancer Discovery 2012). In addition, olaparib has single agent activity in both HGSC and BRCA-associated breast cancer. The PI3kinase pathway is activated in both TNBC and HGSC (www.cancergenome.nih.gov). These preclinical and clinical data have served as the rationale for this phase I, multi-center study (NCT01623349) combining the oral PARP inhibitor olaparib with the oral PI3-kinase inhibitor BKM120 in patients with recurrent HGSC or recurrent TNBC. This study is being conducted through the Stand Up to Cancer (SU2C)'s Targeting PI3-kinase in Women's Cancers Dream Team.

Study Design: This study has a 3 + 3 design, escalating if 0/3 or 1/6 participants have a dose limiting toxicity (DLT) during the first cycle of therapy (first 28 days). The study objectives are to determine the recommended phase II dose (RP2D) of daily continuous oral olaparib (using the tablet formulation) and BKM120, assess toxicities, safety, and preliminary activity of this combination, and determine pharmacokinetic profiles of both agents. In addition, there are several translational endpoints including elucidation of downstream signaling effects of the PI3-kinase pathway, examination of BRCA1 immunostaining, and assessment of BRCA1 promoter hypermethylation and somatic mutations in BRCA1 and BRCA2 using archived formalin fixed paraffin embedded (FFPE) tissue. Serial IL-8 and circulating DNA levels are also being monitored as well. Eligibility includes a diagnosis of recurrent TNBC or HGSC, PS 0 or 1, measurable or evaluable cancer, and normal lab values and organ function. Prior PARP inhibitor exposure is allowed. In addition, breast cancer or ovarian cancer patients with any histologic subtype are eligible if they have a known germline BRCA1 or BRCA2 mutation. At the RP2D, 10 pts each with a diagnosis of TNBC or HGSC will be enrolled to further determine safety and efficacy profiles in addition to more thoroughly studying translational endpoints. As of June 7, 2013, 16 patients have been enrolled into this study with a planned accrual of approximately 50 patients which may change based on number of dose levels tested during dose escalation. In addition, an amendment is pending that will add a second cohort studying the combination of olaparib and BYL719 based on robust pre-clinical activity observed in murine models which will increase our total accrual. Once this new cohort is open, both arms will enroll simultaneously.

For further information, contact Ursula Matulonis at: umatulonis@partners.org.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT1-4-02.

An external focus of attention enhances motor learning in children with intellectual disabilities

BACKGROUND

The present study examined whether the learning benefits of an external focus of attention (i.e., on the movement effect) relative to an internal focus (i.e. on the movement), found previously in non-disabled children and adults would also be found in children with intellectual disabilities (IDs).

METHODS

Participants (n = 24; average age: 12.2 years) with mild intellectual deficiency (IQ = 51-69) practiced throwing beanbags at a target. In the external focus group, participants were instructed to direct their attention to the movement of the beanbag, while in the internal focus group, participants were asked to direct their attention to the movement of their hand. The practice phase consisted of 40 trials, and attentional focus reminders were given after every third trial. Learning was assessed 1 day later by retention and transfer (greater target distance) tests, each consisting of 10 trials. No focus reminders were given on that day.

RESULTS

The external focus group demonstrated more effective learning than the internal focus group, as evidenced by more accurate tosses on the transfer test.

CONCLUSIONS

The present findings show that instructions that induce an external focus of attention can enhance motor learning in children with IDs.

Infectious mononucleosis and risk of breast cancer in a prospective study of women

PURPOSE

The association between infectious mononucleosis (IM) and risk of breast cancer is unclear; no prospective studies have examined this relationship. We examined self-reported history and age at IM in relation to risk of invasive breast cancer.

METHODS

Self-reported history and age at IM were examined in relation to risk of invasive breast cancer in a large cohort of women, the Nurses' Health Study II (81,807 women followed from 1989 to 2007). Through questionnaires, women were asked whether they ever had IM and if so, at what age. During follow-up, 2,349 cases of invasive breast cancer were documented. Cox proportional hazards regression was used to estimate relative risks (RR) and 95 % confidence intervals (CI) for the association of IM with breast cancer.

RESULTS

The multivariable-adjusted RR for history of IM and risk of invasive breast cancer was 1.00 (95 % CI: 0.90-1.11). Similar null results were obtained when estrogen receptor/progesterone receptor positive and negative tumors were considered separately. There were no clear patterns of association between age at IM and risk of breast cancer: compared to women with no history of IM, those who were ≤15 years old when they had IM were at lower risk (RR: 0.77; 95 % CI: 0.60, 0.97), but there was no association for women who had IM at ages 16-19, 20-24, or 30+. However, an increased RR (1.45; 95 % CI: 1.02-2.04) was observed for women who had IM at ages 25-29.

CONCLUSION

Results of this large prospective study do not support a clear association between history of clinical IM and risk of invasive breast cancer.

Frequent feedback enhances complex motor skill learning

Feedback frequency effects on the learning of a complex motor skill, the production of slalom-type movements on a ski-simulator, were examined. In Experiment 1, a movement feature that characterizes expert performance was identified. Participants (N = 8) practiced the task for 6 days. Significant changes across practice were found for movement amplitude and relative force onset. Relative force onset is considered a measure of movement efficiency; relatively late force onsets characterize expert performance. In Experiment 2, different groups of participants (N = 27) were given concurrent feedback about force onset on either 100% or 50% of the practice trials; a control group was given no feedback. The following hypothesis was tested: Contrary to previous findings concerning relatively simple tasks, for the learning of a complex task such as the one used here, a high relative feedback frequency (100%) is more beneficial for learning than a reduced feedback frequency (50%). Participants practiced the task on 2 consecutive days and performed a retention test without feedback on Day 3. The 100% feedback group demonstrated later relative force onsets than the control group in retention; the 50% feedback group showed intermediate performance. The results provide support for the notion that high feedback frequencies are beneficial for the learning of complex motor skills, at least until a certain level of expertise is achieved. That finding suggests that there may be an interaction between task difficulty and feedback frequency similar to the interaction found in the summary-KR literature.

Physical-guidance benefits in learning a complex motor skill

The effects of physical guidance on learning to perform slalom-type movements on a ski-simulator were examined in 22 participants (18 in Experiment 1, 4 in Experiment 2). In Experiment 1, 1 group of participants practiced the task with ski-poles whereas another group practiced without poles. Retention tests without poles were performed at the end of each of the 2 practice days and 1 day later. Although the use of poles produced more effective performance in terms of movement amplitude during practice, both conditions led to similar amplitudes in immediate and delayed retention. With regard to the efficiency of the movement pattern, the pole group demonstrated a more efficient coordination pattern than the no-pole group did, not only during practice but also in immediate (Day 2) and delayed retention. In Experiment 2, how the poles functioned to enhance the learning of a more efficient movement pattern was examined more closely. The results suggest that physical guidance can have beneficial effects not only on performance during practice but also-under certain conditions-on the learning of motor skills.

Instructions for motor learning: differential effects of internal versus external focus of attention

The effects of different types of instructions on complex motor skill learning were examined. The instructions were related either to the participant's own body movements (internal focus) or to the effects of those movements on the apparatus (external focus). The hypothesis tested was that external-focus instructions would be more beneficial for learning than internal-focus instructions. In Experiment 1, the participants (N = 33) performed slalom-type movements on a ski-simulator. The instructions referred to the way in which force should be exerted on the platform that the participant was standing on. The instructions given 1 group of participants referred to the performers' feet (internal focus), whereas the instructions given another group referred to the wheels of the platform, which were located directly under the feet (external focus). The control group was given no focus instructions. All participants practiced the task on 2 consecutive days and performed a retention test on Day 3. Compared with the effects of internal-focus instructions and no instructions, the external-focus instructions enhanced learning. Internal-focus instruction was not more effective than no instructions. In Experiment 2, an attempt was made to replicate the differential effects of external-versus internal-focus instructions with a different task (balancing on a stabilometer). Consistent with Experiment 1, instructing learners (N = 16) to focus on 2 markers on the platform of the stabilometer (external focus) led to more effective learning than instructing them to focus on their feet (internal focus), as measured by a retention test after 2 days of practice. Practical and theoretical implications of those results are discussed.

Tolerability and efficacy of 500 mg fulvestrant in postmenopausal women with estrogen receptor (ER)+ advanced breast cancer

1050

Background: At the approved dosage (AD) of 250 mg q 28d, fulvestrant has no dose-limiting toxicity and may not optimally inhibit/downregulate levels of ER. We evaluated the tolerability, efficacy, and pharmacokinetics of fulvestrant given at twice the AD. Methods: 35 postmenopausal patients with ER+ evaluable metastatic breast cancer who had not received endocrine therapy for advanced disease and were at least 12 months from the completion of any adjuvant endocrine therapy were enrolled in a single stage, phase II study. The median age was 64. 15 patients had received prior adjuvant endocrine treatment. 14 had visceral metastases. Treatment consisted of fulvestrant 500 mg (2 x 5 mL injections) on days 1, 15, 29, and q 28d thereafter. Toxicity and response were assessed q 28d by history, exam, and laboratory testing, and q 3 months by imaging. The primary endpoint was clinical benefit rate (CBR) defined as complete responses (CR) plus partial responses (PR) plus stable disease (SD) for > 6 months. This trial was powered to detect a 20% improvement in the 57% CBR reported for AD fulvestrant in the first-line metastatic setting (J Clin Oncol. 2004;22:1605–613). Results: Median time on study is 13 months (mo). 17 patients remain on treatment (8+ to 54+ mo). There has been no grade (gr) 3 or 4 treatment-related toxicity. Transient injection site discomfort or pruritis occurred in 13 patients (11 gr 1, 2 gr 2). A CBR of 86% was observed (95% CI 70%- 95%). The median time to progression is 22 mo. In the subset of 24 patients fulfilling RECIST criteria, 1 CR and 6 PR, and 15 SD were observed (overall response rate 29%, CBR 92%). Conclusions: Doubling the AD of fulvestrant does not increase toxicity. Monthly bilateral 5 mL injections are well tolerated. Importantly, the CBR is improved at this dose and schedule compared to the AD.

[Table: see text]

Dose-dense (DD) doxorubicin and cyclophosphamide (AC) followed by weekly paclitaxel (P) with trastuzumab (T) and lapatinib (L) in HER2/neu-positive breast cancer is not feasible due to excessive diarrhea: updated results

Abstract #2108

Background: DD q 2 weekly (w) AC → P + T x 1 year (y) has an acceptable safely profile w/ congestive heart failure (CHF) rate of 1/70 pts (Dang, JCO 2008). Lapatinib (L) is effective in HER2 (+) BC. We conducted a pilot study of dd AC → w P + T + L to determine its feasibility and cardiac safety.&#x2028; Methods: Enrolled pts had HER2 (+) BC; LVEF &gt; 50%. Rx consisted of AC at 60/600 mg/m2 x 4 q 2 w (w/ pegfilgrastim 6 mg day 2) → P at 80 mg/m2 x 12 q w + T x 1 y; L (1000 mg daily beginning w/ P + T and continued x 1 y). MUGA is obtained at baseline and at months (mo) 2, 6, 9, and 18. Rx is considered feasible if 1) &gt; 80% pts can complete the PTL phase without a dose delay or reduction and 2) the cardiac event rate (CHF or cardiac death) is &lt; 4%. Pts can remain on-Rx w/ one dose reduction of L (1000 mg → 750 mg) for a G 3 event or &lt; G 3 toxicity (unacceptable).&#x2028; Results: From March 2007 to April 2008, we enrolled 95 pts. Median (med) age was 45 years (range, 28-73). At a med follow-up of 7 months, 90 are evaluable. Of the 90 pts, 34 (37%) withdrew from study during the PTL phase; 29 for a 2nd event of G 3 or unacceptable &lt; G 3 toxicities (15 G 3 diarrhea, 4 G 1/2 diarrhea, 1 G 3 rash, 2 G 2 rash, 1 G 3 dyspnea and also had G 3 diarrhea, 1 G 3 ↑QTc also had G 3 diarrhea, 1 G 3 ↑ALT also had G 3 diarrhea, 1 G 3 paronychia, 1 G 3 pneumonitis, 1 asymptomatic LVEF ↓, 1 myocarditis) and 5 for other reasons (2 personal reason, 1 PCP pneumonia, 1 progression, 1 P hypersensitivity). Overall, 25/90 (27%) pts had G 3 diarrhea and 31/90 (34%) pts required a dose reduction of lapatinib. Med LVEF at baseline is 67% (N=95), at mo 2 is 68% (N=90), at mo 6 is 65% (N=53), and mo 9 is 65% (N=28). To date there are no patient drop-outs due to significant LVEF declines after dd AC; one patient dropped during PTL out due to an asymptomatic LVEF decline.&#x2028; Discussion: L at 1000 mg/day is not feasible combined w/ weekly P and T by protocol stipulation (&gt; 20% pts required L dose reduction) primarily due to excessive G 3 diarrhea. These results have led to the modification of Design 2 (Arm D) of ALTTO. We will report updated results.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2108.

Coexpression of osteogenic and adipogenic differentiation markers in selected subpopulations of primary human mesenchymal progenitor cells

Knowledge of the basic mechanisms controlling osteogenesis and adipogenesis might provide new insights into the prevention of osteoporosis and age-related osteopenia. With the help of magnetic cell sorting and fluorescence activated cell sorting (FACS), osteoblastic subpopulations of mesenchymal progenitor cells were characterized. Alkaline phosphatase (AP) negative cells expressed low levels of osteoblastic and adipocytic markers. AP positive cells expressed adipocytic markers more strongly than the AP negative cell populations, thus suggesting that committed osteoblasts exhibit a greater adipogenic potential. AP negative cells differentiated to the mature osteoblastic phenotype, as demonstrated by increased AP-activity and osteocalcin secretion under standard osteogenic culture conditions. Surprisingly, this was accompanied by increased expression of adipocytic gene markers such as peroxisome proliferator-activated receptor-gamma2, lipoprotein lipase and fatty acid binding protein. The induction of adipogenic markers was suppressed by transforming growth factor-beta1 (TGF-beta1) and promoted by bone morphogenetic protein 2 (BMP-2). Osteogenic culture conditions including BMP-2 induced both the formation of mineralized nodules and cytoplasmic lipid vacuoles. Upon immunogold electron microscopic analysis, osteoblastic and adipogenic marker proteins were detectable in the same cell. Our results suggest that osteogenic and adipogenic differentiation in human mesenchymal progenitor cells might not be exclusively reciprocal, but rather, a parallel event until late during osteoblast development.

Self-tolerance of human natural killer cells lacking self-HLA-specific inhibitory receptors

Natural killer (NK) cells identify cells with altered human leucocyte antigen (HLA) expression as targets through lacking engagement of self-HLA-specific inhibitory receptors (e.g. killer cell immunoglobulin-like receptor, KIR). Thus, they eliminate cells with 'missing self' because of viral or malignant transformation. We performed analysis of HLA, KIR genotypes and KIR receptor expression patterns at single cell level in NK cells in 17 donors. The function of NK cell subsets is determined by degranulation assays using target cells expressing self, cognate, control or no HLA class I. Donors could be grouped into three groups: their NK cells possess potential for alloreactivity, autoreactivity based on the presence of NK cells expressing particular KIR only (mono-KIR) in the absence of its ligand or lack alloreactivity. All donors possess NK cells lacking all detectable inhibitory receptors. Both potential autoreactive subpopulations did not respond to HLA class I-positive target cells. They retain partial reactivity against HLA class I-negative tumour target cells. Mono-KIR NK cells without the corresponding ligands in the individuals and NK cells lacking all inhibitory receptors behave self-tolerant. Our results suggest alternative mechanisms than HLA-specific inhibitory receptors to control NK cell activity. But HLA seems to be involved in shaping effector function of the NK cell repertoire.

Dose-dense nab-paclitaxel (nanoparticle albumin-bound paclitaxel) in adjuvant chemotherapy for breast cancer: A feasibility study

594

Background: We sought to evaluate the feasibility of substituting nab-paclitaxel (ABI-007) for paclitaxel as part of “dose-dense” adjuvant sequential doxorubicin / cyclophosphamide (AC) followed by taxane chemotherapy. Patients and Methods: Eligible patients had stage I-III breast cancer receiving adjuvant/neoadjuvant chemotherapy, ANC > 1500, and LVEF > 50%. Patients received AC (60 mg/m2 and 600 mg/m2) every 2 weeks × 4 cycles with G-CSF support, followed by nab- paclitaxel 260 mg/m2 every 2 weeks × 4 cycles. The endpoint was incidence of treatment delay during nab-paclitaxel therapy. Results: 66 women (median age 48 years) were enrolled. Among the first 11 given nab-paclitaxel without G-CSF support, one developed febrile neutropenia, and 4 had nab-paclitaxel treatment delays related to neutropenia (ANC < 1,000). The protocol was amended to require G-CSF support (filgrastim or pegfilgrastim) during nab-paclitaxel. Among the next 55 patients, 3 had febrile neutropenia, none during nab- paclitaxel. In cycles 6–8, nab-paclitaxel was delayed only 6 times (1 neutropenia, 3 hepatic toxicity, 2 patient scheduling); 96% of these cycles were delivered on time. By comparison, 82% of such cycles were delivered on time in a prior institutional study using paclitaxel. In the full cohort, 8 patients had nab-paclitaxel dose reduction, 4 for neuropathy, while other neuropathy was moderate (grade 2, n = 6; grade 3, n=1; grade 4, n=0). Conclusions: Administration of nab-paclitaxel every 2 weeks is feasible but requires G-CSF support. Data comparing nab-paclitaxel dose-delivery, toxicities and quality of life to paclitaxel as seen in prior studies will be presented.

No significant financial relationships to disclose.

[Asymptomatic 32 year old female smoker with persistent polyclonal lymphocytosis]

A 32 year old female smoker (20 pack years) presented with an asymptomatic lymphocytosis of 13,000/nl and splenomegaly. The patient's blood smear showed an absolute lymphocytosis with 65% atypical lymphocytes. A total of 1% of the lymphocytes were bilobulated. Bone marrow histology and immunphenotyping of blood and bone marrow excluded leukemia and non-Hodgkin's lymphoma. IgH-CDR-3 PCR analysis revealed a polyclonal pattern. In summary, a persistent polyclonal B-cell-lymphocytosis (PPBL) was diagnosed. The exact etiology of PPBL is still unclear, however, it is associated with a polyclonal raise in the lymphocyte count of CD27+IgD+-memory-B-lymphocytes due to a defect in apoptosis signaling and leukocyte homing to secondary lymphoid tissues. An association with cigarette smoking is obvious since all patients are smokers. From all published cases, only two developed a malignancy with an uncertain association with PPBL. We have been monitoring our patient for 6.5 years without any evidence of the development of a lymphoma.

Asthenoteratozoospermia in mice lacking testis expressed gene 18 (Tex18)

Testis expressed gene 18 (Tex18) is a small gene with one exon of 240 bp, which is specifically expressed in male germ cells. The gene encodes for a protein of 80 amino acids with unknown domain. To investigate the function of (Tex18) gene, we generated mice with targeted disruption of the (Tex18) gene by homologous recombination. Homozygous mutant males on a mixed genetic background (C57BL/6J x 129/Sv) are fertile, while they are subfertile on the 129/Sv background, although mating is normal. We showed that Tex18(-/-) males are subfertile because of abnormal sperm morphology and reduced motility, which is called asthenoteratozoospermia, suggesting that (Tex18) affects sperm characteristics. Maturation of spermatids is unsynchronized and partially impaired in seminiferous tubules of Tex18(-/-) mice. Electron microscopical examination demonstrated abnormal structures of sperm head. In vivo experiments with sperm of Tex18(-/-) 129/Sv mice revealed that the migration of spermatozoa from the uterus into the oviduct is reduced. This result is supported by the observation that sperm motility, as determined by the computer-assisted semen analysis system, is significantly affected, compared to wild-type spermatozoa. Generation of transgenic mice containing Tex18-EGFP fusion construct revealed a high transcriptional activity of (Tex18) during spermiogenesis, a process with morphological changes of haploid germ cells and development to mature spermatozoa. These results indicate that (Tex18) is expressed predominantly during spermatid differentiation and subfertility of the male Tex18(-/-) mice on the 129/Sv background is due to the differentiation arrest, abnormal sperm morphology and reduced sperm motility.

Resistance Against Natural Killer Cell Cytotoxicity: Analysis of Mechanisms

Target cell resistance against natural killer (NK) cell-mediated cytotoxicity obstructs NK cell-based immunotherapy of leukaemia. Several mechanisms of resistance have been described. Because of lack of simple assays for analysing these mechanisms, their relative impact on a given effector-target pair is mostly unknown. We here analysed the combination of the Granzyme B (GrB) enzyme-linked immunospot assay (ELISPOT) for the assessment of NK cell reactivity and cytotoxicity assays to estimate target cell escape mechanisms. Target cell recognition failure leads to negative GrB ELISPOT results, whereas target cell resistance shows positive GrB ELISPOT results in the absence of cytotoxicity. We confronted NK cells with the sensitive target cell line K562, and with the resistant cell lines ML2, SupB15 and Raji. ML2 cells sufficiently activated GrB-release whilst being resistant against cytotoxic granules of NK cells. Partial resistance of Raji results from the interaction of HLA class I with inhibitory killer immunglobulin-like receptors (KIR) on the NK cells. Failure of target recognition by HLA class I-KIR interaction, lacking ligands to stimulatory NK cell receptors and partial resistance to cytotoxic granules all contributed to resistance of SupB15. In conclusion, revealing the mechanisms of resistance against NK cell-mediated cytotoxicity may allow improving the results of NK-based immunotherapy.

Tandem HD-chemotherapy and myeloablative radioimmunotherapy with 131I-anti-CD20 rituximab in relapsed and refractory B-cell lymphoma: Results of a phase II study of the German RAIT Study Group

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Background: Radioimmunotherapy has been shown to be effective in CD20 + B-cell lymphomas. Both non-myeloablative as well as myeloablative regimens have been employed for low grade and high grade lymphomas with impressive response rates and remission durations. Recently, the Press group and our group published data on myeloablative 131-I-anti-CD20 RAIT with high response rates and favourable long term survival especially in follicular lymphomas and transformed FL. Therefore, a phase II study is currently being done within the German Radioimmunotherapy Group, interim analysis data are presented. Methods: Patients were to receive R-Dexa-BEAM, followed by BEAM and HD-RAIT 2–6 months after BEAM. 131-I-Rituximab was administered with a maximum kidney and lung dose of 25 Gy. Sample size was calculated to be 16 to evaluate toxicity and feasibility of the tandem approach as primary endpoint. Results: 16 pts with relapsed (14) or primary refractory (2) B-cell lymphomas (FLI,II: 4pts; DLBCL: 4pts (all early relapses); transformed FL: 6 pts; MCL:1 pt, marginal zone lymphoma: 1 pt) were treated with 1 (15 pts) or 2 cycles (1 pt) of R-Dexa-BEAM. 13/16 pts achieving PR (5) or CRu (8) were treated with BEAM, 2 pts with PD and 1 with subdural hematoma were drop outs. After BEAM, 9/13 pts were in CR, 3/13 PR, 1/13 PD. Of 12 responding pts, 6 received HD-RAIT (1 pancytopenia, 1 hepatic, 2 pulmonary toxicity, 3 too early). After HD RAIT, 5/6 pts were in CR, 1 in PR. 4/6 pts (3 CR, 1 PR) are alive for 22–31 months, 2 pts died in CR, 1 of interstitial lung disease 2 months after HD-RAIT, 1 pt of pneumonia 8 months after HD-RAIT. Conclusions: Myeloablative RAIT is a feasible and effective treatment modality for relapsed poor prognosis CD20+ B-NHL not having severe toxicity due to the salvage regimen and HD-chemotherapy. HD RAIT offers the potential for long term relapse free survival. Final analysis of toxicity and outcome of this phase II study will be presented at the meeting.

No significant financial relationships to disclose.

Reduced-intensity conditioning prior to allogeneic transplantation of hematopoietic stem cells: the need for T cells early after transplantation to induce a graft-versus-lymphoma effect

In patients with poor-risk relapse of aggressive lymphoma, reduced-intensity conditioning followed by allogeneic PBSCT may have its limitations because of rapid regrowth of the tumor. We tried to address this problem by intermediate-intensity conditioning followed by allogeneic SCT. A total of 21 patients received fludarabine, busulfan and cyclophosphamide prior to allogeneic SCT. In the first 10 patients, GVHD prophylaxis by CD34+ selection of the grafts was employed (group I). The next 11 patients received nonmanipulated grafts and mycophenolat mofetil plus cyclosporinA (group II). In group I, no GVHD was observed. In contrast, patients in group II had a significant risk of acute GVHD (aGVHD) (six patients with grade II-IV acute GVHD). However, in group I, all surviving patients progressed within 9 months. In contrast, eight of nine surviving patients of group II remain in remission after a median observation time of 10.5 months (range 4-22 months). Survival differed significantly between the groups (P=0.004). Multivariate analysis identified intensive GVHD prophylaxis as important risk factor for survival. These results support the existence of a clinically relevant GVL effect in aggressive lymphoma. T-cell depletion (or CD34 selection) of grafts is not recommended in patients with poor-risk aggressive NHL.

Directing attention to movement effects enhances learning: a review

Studies investigating the influence of the learner's focus of attention, induced by instructions or feedback, on motor skill learning are reviewed. In general, directing performers' attention to the effects of their movements (external focus of attention) appears to be more beneficial than directing their attention to their own movements (internal focus of attention). Preliminary evidence is presented indicating that an internal attentional focus constrains the motor system by interfering with natural control processes, whereas an external focus seems to allow automatic control processes to regulate the movements. Support for the view that actions are controlled by their anticipated effects comes from research demonstrating functional variability in motor control, as well as the benefits of purposeful activity in occupational therapy. We explain these results in terms of the ideomotor principle of human actions (James, 1890) and its more modern derivatives (Hommel, 1996; Prinz, 1990, 1997).

Attention and motor performance: preferences for and advantages of an external focus

This study examined individuad differences in the preference for and effectiveness of the type of attentional focus for motor learning. In two experiments, participants practicing a balance task (stabilometer) were asked to find out whether focusing on their feet (internal focus) or on two markets in front of their feet (external focus) was more effective. In Experiment 1, participants switched their attentional focus from trial to trial on Day 1 and used their preferred attentional focus on Day 2. In Experiment 2, participants were free to switch their attentional focus any time during 2 days of practice. Retention tests were performed on Day 3. Most participants chose an external focus. Also, they were more effective in retention than participants who preferred an internal focus.

The automaticity of complex motor skill learning as a function of attentional focus

The present experiment was designed to test the predictions of the constrained-action hypothesis. This hypothesis proposes that when performers utilize an internal focus of attention (focus on their movements) they may actually constrain or interfere with automatic control processes that would normally regulate the movement, whereas an external focus of attention (focus on the movement effect) allows the motor system to more naturally self-organize. To test this hypothesis, a dynamic balance task (stabilometer) was used with participants instructed to adopt either an internal or external focus of attention. Consistent with earlier experiments, the external focus group produced generally smaller balance errors than did the internal focus group and responded at a higher frequency indicating higher confluence between voluntary and reflexive mechanisms. In addition, probe reaction times (RTs) were taken as a measure of the attention demands required under the two attentional focus conditions. Consistent with the hypothesis, the external focus participants demonstrated lower probe RTs than did the internal focus participants, indicating a higher degree of automaticity and less conscious interference in the control processes associated with the balance task.

Pin1 regulates turnover and subcellular localization of beta-catenin by inhibiting its interaction with APC

Phosphorylation on a serine or threonine residue preceding proline (Ser/Thr-Pro) is a key regulatory mechanism, and the conformation of certain phosphorylated Ser/Thr-Pro bonds is regulated specifically by the prolyl isomerase Pin1. Whereas the inhibition of Pin1 induces apoptosis, Pin1 is strikingly overexpressed in a subset of human tumours. Here we show that Pin1 regulates beta-catenin turnover and subcellular localization by interfering with its interaction with adenomatous polyposis coli protein (APC). A differential-display screen reveals that Pin1 increases the transcription of several beta-catenin target genes, including those encoding cyclin D1 and c-Myc. Manipulation of Pin1 levels affects the stability of beta-catenin in vitro. Furthermore, beta-catenin levels are decreased in Pin1-deficient mice but are increased and correlated with Pin1 overexpression in human breast cancer. Pin1 directly binds a phosphorylated Ser-Pro motif next to the APC-binding site in beta-catenin, inhibits its interaction with APC and increases its translocation into the nucleus. Thus, Pin1 is a novel regulator of beta-catenin signalling and its overexpression might contribute to the upregulation of beta-catenin in tumours such as breast cancer, in which APC or beta-catenin mutations are not common.

Surfing the implicit wave

Implicit learning was investigated in two experiments involving a complex motor task. Participants were required to balance on a stabilometer and to move the platform on which they were standing to match a constantly changing target position. Experiment 1 examined whether a segment (middle third) that was repeated on each trial would be learned without participants becoming aware of the repetitions (i.e., implicitly). The purpose of Experiment 2 was to determine the relative effectiveness of explicit versus implicit learning. Here, two identical segments were presented on each trial (first and last thirds), with participants only being informed that one segment (either first or last) was repeated. The acquisition results from both experiments indicated large improvements in performance across 4 days of practice, with performance on the repeated segments being generally superior to that on the non-repeated segment. On the retention tests on Day 5, errors on the repeated segment(s) were smaller than those on the random segment(s). Furthermore, in Experiment 2, the errors on the repeated-known segment, although smaller than those on the random segment, were larger than those on the repeated-unknown segment. Interview results indicated that participants were not consciously aware that a segment was repeated unless they were informed. These results suggest that implicit learning can occur for relatively complex motor tasks and that withholding information concerning the regularities is more beneficial than providing this information.

Effects of an auditory model on the learning of relative and absolute timing

The effects of an auditory model on the learning of relative and absolute timing were examined. In 2 experiments, participants attempted to learn to produce a 1,000- or 1,600-ms sequence of 5 key presses with a specific relative-timing pattern. In each experiment, participants were, or were not, provided an auditory model that consisted of a series of tones that were temporally spaced according to the criterion relative-timing pattern. In Experiment 1, participants (n = 14) given the auditory template exhibited better relative- and absolute-timing performance than participants (n = 14) not given the auditory template. In Experiment 2, auditory and no-auditory template groups again were tested, but in that experiment each physical practice participant (n = 16) was paired during acquisition with an observer (n = 16). The observer was privy to all instructions as well as auditory and visual information that was provided the physical practice participant. The results replicated the results of Experiment 1: Relative-timing information was enhanced by the auditory template for both the physical and observation practice participants. Absolute timing was improved only when the auditory model was coupled with physical practice. Consistent with the proposal of D. M. Scully and K. M. Newell (1985), modeled timing information in physical and observational practice benefited the learning of the relative-timing features of the task, but physical practice was required to enhance absolute timing.

Telomeric protein Pin2/TRF1 induces mitotic entry and apoptosis in cells with short telomeres and is down-regulated in human breast tumors

Telomeres are essential for cell survival and have been implicated in the mitotic control. The telomeric protein Pin2/TRF1 controls telomere elongation and its expression is tightly regulated during cell cycle. We previously reported that overexpression of Pin2/TRF1 affects mitotic progression. However, the role of Pin2/TRF1 at the interface between cell division and cell survival remains to be determined. Here we show that overexpression of Pin2 induced apoptosis in cells containing short telomeres, but not in cells with long telomeres. Furthermore, before entering apoptosis, Pin2-expressing cells first accumulated in mitosis and strongly stained with the mitosis-specific MPM2 antibody. Moreover, Pin2-induced apoptosis is potentiated by arresting cells in mitosis, but suppressed by accumulating cells in G1. In addition, overexpression of Pin2 also resulted in activation of caspase-3, and its proapoptotic activity was significantly reduced by inhibition of caspase-3. These results indicate that up-regulation of Pin2/TRF1 can specifically induce entry into mitosis and apoptosis, likely via a mechanism related to activation of caspase-3. Significantly, we also found that, out of 51 human breast cancer tissues and 10 normal controls examined, protein levels of Pin2/TRF1 in tumors were significantly lower than in normal tissues, as detected by immunoblotting analysis and immunocytochemistry. Since down-regulation of Pin2/TRF1 allows cells to maintain long telomeres, these results suggest that down-regulation of Pin2/TRF1 may be important for cancer cells to extend their proliferative potential.