Romiplostim for management of chemotherapy-induced thrombocytopenia.

PURPOSE: Chemotherapy-induced thrombocytopenia (CIT) can cause delay or reduction in subsequent courses of chemotherapy. Here, we report on a series of 20 patients who had protracted CIT and were treated with romiplostim, a thrombopoietin receptor agonist. PATIENTS AND METHODS: We performed a retrospective review of the use of romiplostim for dose-limiting CIT at Memorial Sloan-Kettering Cancer Center from 2010-2012. Romiplostim was initiated at 1-2 mcg/kg weekly, with dose escalation by 1 mcg/kg per week until recovery of platelets (≥ 100 × 10(9)/L). If patients resumed chemotherapy, weekly romiplostim was continued. RESULTS: Romiplostim improved platelet counts in all 20 patients. In 19 of 20 patients, platelet counts of ≥ 100 × 10(9)/L were achieved. The mean dose of romiplostim to achieve adequate platelet recovery was 2.9 mcg/kg (range 1.0-5.1). Sixteen patients achieved platelet recovery by 2 weeks. Fifteen patients resumed cytotoxic chemotherapy with continued romiplostim support and 14 tolerated at least two subsequent cycles of chemotherapy, on schedule, without recurrence of dose-limiting CIT. Sepsis prevented continued chemotherapy in one patient. No resistance to romiplostim was observed. Three deep vein thromboses (DVT) were observed; one of which was a recurrent DVT in a patient who had previously experienced a DVT and was off anticoagulation. Three DVTs within 20 patients is within the anticipated thrombosis rates of patients with active cancer on chemotherapy. CONCLUSION: Romiplostim resulted in improvement in platelet counts, allowing resumption of chemotherapy without recurrence of dose-limiting CIT. No treatment-related toxicity was observed, but this would need to be confirmed in a larger, prospective trial. Our series differs from prior studies in that we selected only those patients who had already demonstrated persistent thrombocytopenia, and we continued weekly romiplostim during chemotherapy. Romiplostim may be a safe and effective treatment for CIT.

Risk factors for developing a new venous thromboembolism in ambulatory patients with non-hematologic malignancies and impact on survival for gastroesophageal malignancies.

BACKGROUND: Venous thromboembolism(VTE) is a significant, common comorbidity of cancer patients associated with increased mortality. We evaluated the incidence and risk factors for developing a new VTE in ambulatory cancer patients while they were receiving therapy for advanced cancer. We also examined the affect of developing a new VTE on survival for patients with gastroesophageal malignancies. METHODS: All patients with non-hematologic malignancies who were treated using investigator-initiated therapeutic protocols at Memorial Sloan Kettering Cancer Center (MSKCC) from 2003 through to 2005 were identified for this cohort study. The occurrence of VTE was prospectively recorded in an actively managed clinical research database. Baseline laboratory parameters, treatment details and tumor type were correlated with VTE risk and patient survival. RESULTS: 115 out of 2120 patients being treated for advanced malignancy developed a new VTE (12.8 VTEs/100 person-years). In multivariate analysis, a diagnosis of gastroesophageal cancer (hazard ratio (HR), 2.76 (1.41-5.38); P=0.003), pancreatic cancer (HR, 2.26 (1.06-4.80); P=0.05), use of white cell growth factors (HR 1.69(1.09-2.64); P=0.02) and irinotecan therapy (HR, 1.89 (1.29-3.59); P=0.05) were independently associated with VTE development. Hemoglobin >10 g dL(-1) (HR, 0.52 (0.3-0.91); P=0.02) and albumin ≥ 4 g dL(-1) (HR, 0.61 (0.39-0.94); P=0.024) were associated with reduced VTE risk. The unadjusted HR for death among ambulatory gastroesophageal cancer patients with VTE is 0.89 (0.61-1.3), P=0.53. After adjusting for confounding risk factors associated with survival, the HR for death associated with VTE is 0.78 (0.5-1.2), P=0.25. CONCLUSION: Upper gastrointestinal malignancies are independently associated with the development of a new VTE, implicating tumor biology in VTE development. Even after adjusting for prognostic factors, we were unable to demonstrate an adverse impact on survival due to the new development of VTE amongst patients with active gastroesophageal malignancy receiving therapy.

Clinical Study on the Management of Huzaz/Abria (Dandruff) with a pharmacopoeal Preparation of a Unani Medicine and its Cosmetic Evaluation.

Dandruff called Huzaz/Abria in Unani medicine is a common ailment in the world with easy options of treatment. Most of the treatment options have ignored the cosmetic aspect of hair. Unani medicine has got a vast array of drug formulation to evaluate the efficacy of Unani pharmacopoeal formulation in mild form of seborrhic dermatitis of scalp (dandruff). Its efficacy was compared with standard drug (2% ketakonazole shampoo). Patients were enrolled after ethical clearance and informed consent in the study. 30 patients were treated with Unani formulation and 20 patients with the standard drug. The assessment of various parameters like Itching, Scalp shedding, Erythema, Hair frizz, Hair combing ease, and Hair smoothness was made before and after 30 days. The assessments of the parameters were analyzed and compared using appropriate statistical tests. The study revealed that Unani formulation was equally effective as standard drug and the hair comesis was better than the standard drug as seen clinically, but was not statistically significant (p=0.576).

Dual kinetic balance approach to basis-set expansions for the dirac equation.

A new approach to finite basis sets for the Dirac equation is developed. It does not involve spurious states and improves the convergence properties of basis-set calculations. Efficiency of the method is demonstrated for finite basis sets constructed from B splines by calculating the one-loop self-energy correction for a hydrogenlike ion.

Nuclear-polarization correction to the bound-electron g factor in heavy hydrogenlike ions.

The influence of nuclear polarization on the bound-electron g factor in heavy hydrogenlike ions is investigated. Numerical calculations are performed for the K- and L-shell electrons taking into account the dominant virtual nuclear excitations. This determines the ultimate limit for tests of QED utilizing measurements of the bound-electron g factor in highly charged ions.

Vacuum-polarization corrections to the parity-nonconserving 6s-7s transition amplitude in (133)Cs.

The dominant one-loop radiative corrections to atomic wave functions, those associated with vacuum polarization in the nuclear Coulomb field, are evaluated for the 6s-7s parity-nonconserving transition amplitude in (133)Cs. These corrections increase the size of this amplitude by 0.4% and, correspondingly, increase the difference between the experimental value of the weak charge Q(W)((133)Cs) and the value predicted by the standard model.

Asymmetry of the natural line profile for the hydrogen atom.

The asymmetry of the natural line profile for transitions in hydrogenlike atoms is evaluated within a QED framework. For the Lyman- alpha 1s-2p absorption transition in neutral hydrogen this asymmetry results in an additional energy shift of 2.929 856 Hz. For the 2s(1/2)-2p(3/2) transition it amounts to -1.512 674 Hz. As a new feature this correction turns out to be process dependent. The quoted numbers refer to the Compton-scattering process.

CD34(+) cell collection efficiency does not correlate with the pre-leukapheresis hematocrit.

One hundred and seventy-seven large-volume leukapheresis procedures performed on 91 patients over a 15 month period were reviewed to see if the pre-apheresis hematocrit (Hct) affected the CD34(+) cell collection efficiency (CE) of the Fenwal CS 3000 Plus cell separator. The Hct was 0.174-0.461 (median 0.317), and the peripheral blood CD34(+) cell count 2-2487 per microl (median 21). The total CD34(+) cell quantity collected was 3.0-2677.2 x 10(6) (median 113.0). Based on the number of CD34(+)cells contained in the blood volume processed (23.3-37303.2 x 10(6); median 318.0), the CE was 1.7-87.5% (median 30.3). No correlation was found between the Hct and CE (r(2) = 0.0034; P = 0.44) or the total CD34(+) cell quantity collected (r2 = 0.0040; P = 0.40). CEs for Hct <0.25 (median CE 36%), Hct 0.25-0.299 (median CE 30%) and Hct 0.30 (median CE 30%) were comparable. As expected, highly significant correlations were seen between the CD34(+) cell quantities collected and quantities processed (r2 = 0.59; P < 10(-6)) as well as the peripheral blood CD34(+) cell counts (r2= 0.60; P < 10(-6)). We conclude that the minimum acceptable Hct or hemoglobin level for leukapheresis should be dictated by clinical circumstances because it does not affect stem cell collection.

Towards a test of QED in investigations of the hyperfine splitting in heavy ions.

A possibility for investigations of quantum electrodynamics (QED) in experiments on the hyperfine splitting in heavy ions is examined. It is found that QED effects can be probed on the level of a few percent in a specific difference of the hyperfine splitting values in hydrogenlike and lithiumlike bismuth. This could provide a test of QED in the strongest electric field available at present for experimental study.

Two-photon exchange corrections to the 2p(1/2)-2s transition energy in Li-like high- Z ions

A rigorous QED calculation of the two-photon exchange corrections to the 2p(1/2)- 2s transition energy in Li-like high- Z ions is presented. The contribution due to an exchange by more than two photons is evaluated within the Breit approximation. The resulting theoretical value of the 2p(1/2)- 2s transition energy in Li-like uranium is found to be 280.44(20) eV.

Hyperfine structure of highly charged 23892U ions with rotationally excited nuclei

The hyperfine structure (hfs) of electron levels of 23892U ions with the nucleus excited in the low-lying rotational 2(+) state with an energy E(2(+)) = 44.91 keV is investigated. In hydrogenlike uranium, the hfs splitting for the 1s(1/2) ground state of the electron constitutes 1.8 eV. The hyperfine-quenched (hfq) lifetime of the 1s2p 3P0 state has been calculated for heliumlike 23892U and was found to be 2 orders of magnitude smaller than for the ion with the nucleus in the ground state. The possibility of a precise determination of the nuclear g(r) factor for the rotational 2(+) state by measurements of the hfq lifetime is discussed.

Dynamical casimir effect at finite temperature

Thermal effects on the creation of particles under the influence of time-dependent boundary conditions are investigated. The dominant temperature correction to the energy radiated by a moving mirror is derived by means of response theory. For a resonantly vibrating cavity the thermal effect on the number of created photons is obtained nonperturbatively. Finite temperatures can enhance the pure vacuum effect by several orders of magnitude. The relevance of finite-temperature effects for the experimental verification of the dynamical Casimir effect is addressed.

Resummation of QED perturbation series by sequence transformations and the prediction of perturbative coefficients

We propose a method for the resummation of divergent perturbative expansions in quantum electrodynamics and related field theories. The method is based on a nonlinear sequence transformation and uses as input data only the numerical values of a finite number of perturbative coefficients. The results obtained in this way are for alternating series superior to those obtained using Pade approximants. The nonlinear sequence transformation fulfills an accuracy-through-order relation and can be used to predict perturbative coefficients. In many cases, these predictions are closer to available analytic results than predictions obtained using the Pade method.

A pilot trial of suramin in metastatic breast cancer to assess antiangiogenic activity in individual patients.

Suramin is a polysulfonated naphthylurea with multiple potential mechanisms of action against tumors, including the ability to bind growth factors known to promote tumor angiogenesis. Using an established fixed dosing scheme for the administration of suramin in patients, a pilot study was conducted in patients with progressive, metastatic breast cancer. The primary objective of this trial is to define the effect of suramin on the angiogenic activity in individual patients using in vitro laboratory assays. The secondary objective was to assess the antitumor effect of suramin in a population of metastatic breast cancer patients. No objective tumor responses were observed in any of the 9 patients who received treatment with suramin, however 1 patient did maintain stable disease status. The strength of angiogenic activity present in patient samples was assessed by testing patient plasma in the capillary endothelial cell migration assay. Angiogenic activity followed over time was lowest in patients with the highest suramin concentrations and highest in patients with the lowest suramin concentrations. We conclude that it is feasible to continually monitor the activity of antiangiogenic agents in individual patients without relying on clinical tumor response.

Angiostatin and angiostatin-related proteins.

The study of angiogenesis, and the promise of angiogenesis inhibition as a means of cancer therapy, has dramatically accelerated in the last several years. The discovery and publication of angiostatin by O'Reilly and colleagues in Judah Folkman's lab in 1994 has greatly contributed to this progress. Angiostatin is a kringle-containing fragment of plasminogen, which is a potent inhibitor of angiogenesis in vivo, and selectively inhibits endothelial cell proliferation and migration in vitro. There have been a number of proposed proteolytic mechanisms by which plasminogen is cleaved to form angiostatin, and the resulting cleavage products contain different NH2 and COOH termini of the angiostatin. Therefore, it is possible that there are more than one angiostatin isoforms (or angiostatin-related proteins) which occur in one or more normal or pathophysiological situations. It is also possible that some of the proteolytic processes which can convert plasminogen to angiostatin-like proteins are simply laboratory artifacts. Angiostatin-related proteins exert potent endothelial cell inhibitory activity, including the induction of apoptosis, and inhibition of migration, and the intact kringle structures are believed to be necessary for the antiangiogenic activity. Efforts are now underway to translate the understanding of the biology of angiostatin to clinical practice, which includes phase 1 clinical trials with recombinant angiostatin K1-3 (kringles 1-3) as well as phase 1 trials of an Angiostatin Cocktail, which induces the direct in vivo conversion of plasminogen to angiostatin 4.5 (kringles 1-4, plus most of kringle 5). The translation of the basic science of angiostatin and angiostatin-related proteins to clinical trial promises to provide an important new tool in the treatment of cancer by inhibition of angiogenesis.

Tumor-host interactions in the gallbladder suppress distal angiogenesis and tumor growth: involvement of transforming growth factor beta1.

Angiogenesis inhibitors produced by a primary tumor can create a systemic anti-angiogenic environment and maintain metastatic tumor cells in a state of dormancy. We show here that the gallbladder microenvironment modulates the production of transforming growth factor (TGF)-beta1, a multifunctional cytokine that functions as an endogenous anti-angiogenic and anti-tumor factor in a cranial window preparation. We found that a wide variety of human gallbladder tumors express TGF-beta1 irrespective of histologic type. We implanted a gel impregnated with basic fibroblast growth factor or Mz-ChA-2 tumor in the cranial windows of mice without tumors or mice with subcutaneous or gallbladder tumors to study angiogenesis and tumor growth at a secondary site. Angiogenesis, leukocyte-endothelial interaction in vessels and tumor growth in the cranial window were substantially inhibited in mice with gallbladder tumors. The concentration of TGF-beta1 in the plasma of mice with gallbladder tumors was 300% higher than that in the plasma of mice without tumors or with subcutaneous tumors. In contrast, there was no difference in the plasma levels of other anti- and pro-angiogenic factors. Treatment with neutralizing antibody against TGF-beta1 reversed both angiogenesis suppression and inhibition of leukocyte rolling induced by gallbladder tumors. TGF-beta1 also inhibited Mz-ChA-2 tumor cell proliferation. Our results indicate that the production of anti-angiogenesis/proliferation factors is regulated by tumor-host interactions.

Angiostatin inhibits endothelial and melanoma cellular invasion by blocking matrix-enhanced plasminogen activation.

Angiostatin, a kringle-containing fragment of plasminogen, is a potent inhibitor of angiogenesis. The mechanism(s) responsible for the anti-angiogenic properties of angiostatin are unknown. We now report that human angiostatin blocks plasmin(ogen)-enhanced in vitro invasion of tissue plasminogen activator (t-PA)-producing endothelial and melanoma cells. Kinetic analyses demonstrated that angiostatin functions as a non-competitive inhibitor of extracellular-matrix (ECM)-enhanced, t-PA-catalysed plasminogen activation, with a Ki of 0.9+/-0.03 microM. This mechanism suggests that t-PA has a binding site for the inhibitor angiostatin, as well as for its substrate plasminogen that, when occupied, prevents ternary complex formation between t-PA, plasminogen and matrix protein. Direct binding experiments confirmed that angiostatin bound to t-PA with an apparent Kd [Kd(app)] of 6.7+/-0.7 nM, but did not bind with high affinity to ECM proteins. Together, these data suggest that angiostatin in the cellular micro-environment can inhibit matrix-enhanced plasminogen activation, resulting in reduced invasive activity, and suggest a biochemical mechanism whereby angiostatin-mediated regulation of plasmin formation could influence cellular migration and invasion.

Multiple forms of angiostatin induce apoptosis in endothelial cells.

Angiostatin is a circulating inhibitor of angiogenesis generated by proteolytic cleavage of plasminogen. In this study we have used recombinant human and murine angiostatins (kringles 1-4) as well as native human angiostatin (prepared by elastase digestion of plasminogen [kringles 1-3] or by plasmin autocatalysis in the presence of a free sulfhydryl donor [kringles 1-4]). We report that angiostatin reduces endothelial cell number in a 4-day proliferation assay without affecting cell cycle progression into S-phase (as determined by bromodeoxyuridine labeling). This suggested that the reduction in cell number in the proliferation assay might in part be due to cytotoxicity. This was confirmed by the observation that ethidium homodimer incorporation (a measure of plasma membrane integrity) into endothelial cells was increased by angiostatin in a manner similar to that seen with tumor necrosis factor- (TNF-) and transforming growth factor-beta1 (TGF-beta1), both of which induce apoptosis in endothelial cells. In contrast to TNF- and TGF-beta1, angiostatin did not induce cytotoxicity in human MRC-5 fibroblast, rat smooth muscle, canine MDCK epithelial, or murine B16-F10 melanoma cell lines. Angiostatin-induced apoptosis was confirmed by endothelial cell nuclear acridine orange incorporation as well as by annexin V and TUNEL staining. These in vitro findings point to endothelial cell apoptosis as a mechanism for the antiangiogenic effect of angiostatin in vivo.

Potentiation of the antitumor effect of ionizing radiation by brief concomitant exposures to angiostatin.

Angiostatin, a proteolytic fragment of plasminogen, inhibits the growth of primary and metastatic tumors by suppressing angiogenesis. When used in combination with ionizing radiation (IR), angiostatin demonstrates potent antitumor synergism, largely caused by inhibition of the tumor microvasculature. We report here the temporal interaction of angiostatin and IR in Lewis lung carcinoma (LLC) tumors growing in the hind limbs of syngeneic mice. Tumors with an initial mean volume of 510 +/- 151 mm3 were treated with IR alone (20 Gy x 2 doses on days 0 and 1), angiostatin alone (25 mg/kg/day divided twice daily) on days 0 through 13, or a combination of the two as follows: (a) IR plus angiostatin (days 0 through 13); (b) IR plus angiostatin (days 0 and 1); and (c) IR followed by angiostatin beginning on the day after IR completion and given daily thereafter (days 2 through 13). By day 14, tumors in untreated control mice had grown to 6110 +/- 582 mm3, whereas in mice treated with: (a) IR alone, tumors had grown to 2854 +/- 338 mm3 (P < 0.05 compared with untreated controls); and (b) angiostatin alone, tumors had grown to 3666 +/- 453 mm3 (P < 0.05 compared with untreated controls). In combined-treatment groups, in mice treated with: (a) IR plus longer-course angiostatin, tumors reached 2022 +/- 282 mm3 (P = 0.036 compared with IR alone); (b) IR followed by angiostatin, tumors reached 2677 +/- 469 mm3 (P > 0.05 compared with IR alone); and (c) IR plus short-course angiostatin, tumors reached 1032 +/- 78 mm3 (P < 0.001 compared with IR alone). These findings demonstrate that the efficacy of experimental radiation therapy is potentiated by brief concomitant exposure of the tumor vasculature to angiostatin.