Author Correction: Clinical Implications of Sub-grouping HER2 Positive Tumors by Amplicon Structure and Co-amplified Genes.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Clinical Implications of Sub-grouping HER2 Positive Tumors by Amplicon Structure and Co-amplified Genes.

ERBB2 amplification is a prognostic marker for aggressive tumors and a predictive marker for prolonged survival following treatment with HER2 inhibitors. We attempt to sub-group HER2+ tumors based on amplicon structures and co-amplified genes. We examined five HER2+ cell lines, three HER2+ xenographs and 57 HER2+ tumor tissues. ERBB2 amplification was analyzed using digital droplet PCR and low coverage whole genome sequencing. In some HER2+ tumors PPM1D, that encodes WIP1, is co-amplified. Cell lines were treated with HER2 and WIP1 inhibitors. We find that inverted duplication is the amplicon structure in the majority of HER2+ tumors. In patients suffering from an early stage disease the ERBB2 amplicon is composed of a single segment while in patients suffering from advanced cancer the amplicon is composed of several different segments. We find robust WIP1 inhibition in some HER2+ PPM1D amplified cell lines. Sub-grouping HER2+ tumors using low coverage whole genome sequencing identifies inverted duplications as the main amplicon structure and based on the number of segments, differentiates between local and advanced tumors. In addition, we found that we could determine if a tumor is a recurrent tumor or second primary tumor and identify co-amplified oncogenes that may serve as targets for therapy.

Primary peg-filgrastim prophylaxis versus filgrastim given "on demand" for neutropenia during therapy with cladribine for hairy cell leukemia.

BACKGROUND: Major advances in the treatment of patients with hairy cell leukemia (HCL) have been made following the introduction of purine analogues. The major significant short-term toxicity of cladribine therapy are neutropenia and neutropenic fever (NF) which may be life-threatening. AIM: In this retrospective study, we compared the incidence and duration of neutropenia and hospitalization in patients with HCL treated with cladribine followed by peg-filgrastim as primary prophylaxis versus daily filgrastim given "on demand" according to absolute neutrophil count (ANC). METHODS: Medical records of patients with HCL diagnosed and followed in 12 medical centers in Israel during 1985-2015 were examined for details of disease at diagnosis. The efficacy of peg-filgrastim and filgrastim was assessed by evaluating the incidence of neutropenia (ANC < 1.0 × 10 [9]/L), number and length of hospitalizations, and number of days from the last day of therapy to recovery of ANC to >1.0 × 10 [9]/L. RESULTS: The study population included 202 patients with HCL, 159 of whom (80.7%) were treated with cladribine; 78 patients (49%) required hospitalization for the administration of broad-spectrum antibiotics due to NF. Twenty-eight (19%) patients were treated with peg-filgrastim as primary prophylaxis, while 74 (64%) received filgrastim "on demand" due to neutropenia. Median length of hospitalization, and nadir duration were 8 and 18 days respectively (p = 0.71, p = 0.44). CONCLUSIONS: Infectious complications post-cladribine treatment remain high. No difference was found in terms of incidence of NF, number of febrile days, and nadir duration in patients receiving primary peg-filgrastim prophylaxis compared to filgrastim given on demand. Both approaches are justifiable, and the choice remains at the physician's discretion.

Direct Induction of the Three Pre-implantation Blastocyst Cell Types from Fibroblasts.

Following fertilization, totipotent cells undergo asymmetric cell divisions, resulting in three distinct cell types in the late pre-implantation blastocyst: epiblast (Epi), primitive endoderm (PrE), and trophectoderm (TE). Here, we aim to understand whether these three cell types can be induced from fibroblasts by one combination of transcription factors. By utilizing a sophisticated fluorescent knockin reporter system, we identified a combination of five transcription factors, Gata3, Eomes, Tfap2c, Myc, and Esrrb, that can reprogram fibroblasts into induced pluripotent stem cells (iPSCs), induced trophoblast stem cells (iTSCs), and induced extraembryonic endoderm stem cells (iXENs), concomitantly. In-depth transcriptomic, chromatin, and epigenetic analyses provide insights into the molecular mechanisms that underlie the reprogramming process toward the three cell types. Mechanistically, we show that the interplay between Esrrb and Eomes during the reprogramming process determines cell fate, where high levels of Esrrb induce a XEN-like state that drives pluripotency and high levels of Eomes drive trophectodermal fate.

Hairy Cell Leukemia: Retrospective Analysis of Demographic Data and Outcome of 203 Patients from 12 Medical Centers in Israel.

BACKGROUND/AIM: In this retrospective study, we summarized the national Israeli experience with hairy cell leukemia (HCL) in a large cohort of patients with a long follow-up. PATIENTS AND METHODS: Demographic data, and relevant laboratory and clinical parameters were analyzed, emphasizing the outcome after first-line treatment with cladribine. RESULTS: Data on 203 patients was collected from 12 medical centers during 1985-2015. Mean and median follow-up were 7.5 years and 5.18 years (interquartile range=0.1-40 years), and 5- and 10-year survival were 96% and 90.62%, respectively. The median age of diagnosis was 55.5 years for Jews and 49 years for Arabs (p=0.021), and most patients were males (81.77%); 52.2% were Ashkenazi Jews, 36.1% Sephardic Jews and 11.7% were Arab, Druze or other ethnicity. Cladribine was given to 159 patients (80.7%%) and most (62%) received intravenous (i.v.) and 38% received subcutaneous (s.c.) therapy. Overall survival and time to next treatment were not significantly different between the two schedules (i.v., s.c.). In univariate analysis of a variety of factors, only age >65 years had a negative impact on outcome, with shorter overall survival. It is of interest that Arab patients with HCL were diagnosed at an earlier age, but had a similar clinical course and outcome to both Ashkenazi and Sephardic Jews.

Phase Ib Safety, Two-Dose Study of MultiGeneAngio in Patients with Chronic Critical Limb Ischemia.

Critical limb ischemia (CLI) is the most severe presentation of peripheral arterial disease. We developed cell-based therapy entailing intra-arterial injection of autologous venous endothelial cells (ECs) modified to express angiopoietin 1, combined with autologous venous smooth muscle cells (SMCs) modified to express vascular endothelial growth factor. This combination promoted arteriogenesis in animal models and was safe in patients with limiting claudication. In an open-label, phase Ib study, we assessed the safety and efficacy of this therapy in CLI patients who failed or were unsuitable for surgery or intravascular intervention. Of 23 patients enrolled, 18 with rest pain or non-healing ulcers (Rutherford categories 4 and 5) were treated according to protocol, and 5 with significant tissue loss (Rutherford 6) were treated under compassionate treatment. Patients were assigned randomly to receive 1 × 107 or 5 × 107 (EC-to-SMC ratio, 1:1) of the cell combination. One-year amputation-free survival rate was 72% (13/18) for Rutherford 4 and 5 patients; all 5 patients with Rutherford 6 underwent amputation. Of the 12 with unhealing ulcers at dosing, 6 had complete healing and 2 others had >66% reduction in ulcer size. Outcomes did not differ between the dose groups. No severe adverse events were observed related to the therapy.

Leptin signaling and apoptotic effects in human prostate cancer cell lines.

BACKGROUND: Prostate cancer (PCa) progression is often associated with transactivation of the androgen receptor (AR) by endogenous hormones/growth factors. One such factor affecting growth, proliferation, and apoptostis (pro-/anti-) in various cancers is the adipokine leptin. This research studied leptin-induced signaling and apoptosis in androgen sensitive (LNCaP, PC3/AR) and insensitive (PC3, DU145) PCa cell lines. METHODS: Signaling was studied by immunoblotting in cells overexpressing leptin receptors (LRb), Janus kinase 2 (JAK2), and kinase negative-HER2-YFP cDNAs. Apoptosis was measured by immunoblotting of apoptotic proteins and by Hoechst staining of condensed DNA. RESULTS: Leptin rapidly induced activation of JAK2, STAT3, and MAPK (ERK1/2) signaling cascades; it may also induce HER2 transactivation via leptin-induced phospho-JAK2. Leptin was then shown to exert clear pro-apoptotic effects, increasing levels of caspase 3, cleavage of its substrate, poly (ADP-ribose) polymerase (PARP) to cleaved PARP(89) , levels of CK 18, a cytoskeletal protein formed during apoptosis, and DNA condensation. Kinase inhibitors indicated that leptin-induced apoptosis is probably mediated by balanced activation of JAK2/STAT3, p38 MAPK, and PKC pathways in PCa cells. A human leptin mutein LRb antagonist, L39A/D40A/F41A, fully inhibited leptin-induced phosphorylation of JAK2, ERK1/2, and Akt/PKB, and partially abrogated effects on apoptotic proteins. In LNCaP and PC3/AR cells, leptin increased AR protein levels in correlation with raised apoptotic markers. Thus, AR may mediate, at least partly, the leptin-induced apoptotic response. CONCLUSIONS: Leptin can clearly induce apoptosis in human PCa cell lines. These findings could lead to development of new leptin agonists with enhanced pro-apoptotic effects and targeted for use in human PCa.