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Platinum compounds (cisplatin, carboplatin, and oxaliplatin) are a category of chemotherapeutics widely used in the therapy of various cancers because of their high efficacy and tolerability. Cases of hypersensitivity reactions to these compounds have increased in recent decades due to their frequent use. Carboplatin is the platinum compound associated with the highest incidence of immediate hypersensitivity reactions. It is critical for clinicians to be familiar with allergy diagnostics and to correctly diagnose immediate hypersensitivity reactions to platinum compounds and to identify sensitized patients to both reduce the risk of severe reactions and to continue effective chemotherapy treatment.

The Pt(II) acetylacetonate complex [(L)Pt(Acac)] based on aminophenyl-substituted 2-(2-thienyl)pyridine (L) was synthesized, its photophysical properties were studied and compared with these properties for a similar complex containing no amino group in the ligand. The structure of the complex was confirmed by X-ray diffraction (CIF file CCDC no. 2144689), 1H and 13C NMR spectroscopy, ESI mass spectrometry, and elemental analysis. © 2022, Pleiades Publishing, Ltd.

The discrepancy between the bright theoretical projections for two-dimensional (2D) Janus structures and the lack of experimental realisation of these structures motivated us to study the effect of structural disorder on the stability of MoSSe, SnSSe, PtSSe, In2SSe and GaInSe2. The calculation results demonstrate that the difference between metal-sulfur and metal-selenium bonds makes Janus structures frustrated and less energetically favourable than less ordered allotropes of the same compounds. This result explains the difficulties encountered in the experimental fabrication of these materials. In the bulk, there is an additional contribution to the total energy from dipole-dipole interactions between layers with a Janus structure that can overcome the energetic cost of structural frustration in layers for compounds with sufficiently large dipole moments. However, the entropic contribution to the free energy decreases the favourability of the ordered Janus structure. The calculation results are used to make recommendations to enable the discovery and synthesis of 2D materials with Janus structures. © 2022 The Royal Society of Chemistry.

Platinum (Pt) is a widely used electrocatalyst material in fuel cells and electrolysers. Proton exchange membrane (PEM) fuel cells and electrolysis operate under highly acidic conditions whereas the more recently developed anion exchange membrane (AEM) processes take place under alkaline conditions. Pt dissolution and Pt oxidation during operation and varying potentials has been studied mainly for the acidic PEM and less for the alkaline AEM. This study presents a comparison of Pt dissolution and Pt oxidation in 0.5 M H2SO4 and 1 M KOH using electrochemical quartz crystal microbalance (EQCM) on Pt thin films. Physical characterisation using electron microscopy and atomic force microscopy (AFM) revealed small, yet significant differences in the Pt film surface structure, which is related to differences in measured electrochemical surface area (ECSA). The mass increase from adsorption of oxygenated species and Pt oxidation is higher in alkaline conditions compared to in acid while dissolution of Pt is similar., QC 20230613

Liquid-phase exfoliation (LPE) has been introduced as a versatile and scalable production method for two-dimensional (2D) materials. This method yields dispersions that allow for the fabrication of printable and flexible electronic devices. However, the fabrication of uniform and homogeneous films from LPE dispersions with a performance similar to that of bottom-up grown materials remains a challenge, as the film quality strongly influences the optical and electrical performance of devices. Furthermore, long-term stability remains a major challenge for all 2D material based applications. In this study, we report on highly conductive tiled network films made of platinum diselenide (PtSe2) flakes derived using a scalable LPE method. We characterized the homogeneous films in terms of morphology and electrical behavior. As an example of applicability, we produce a chemiresistive sensor structure with the PtSe2 films and show significant resistance changes upon periodic ammonia gas exposures, revealing a sub-0.1 part per million (ppm) detection limit (DL). More remarkably the devices are fully functional after 15 months, underlining the high stability of PtSe2 based devices.

Transition-metal dichalcogenides PtTe2, PdTe2, and NiTe2 deserve particular attention, due to the presence of type-II Dirac fermions. As a matter of fact, tilted Dirac cones afford a suitable platform for optoelectronics of dissipation-less carrier-transport, favored by their ultrahigh carrier mobility, and large nonsaturating magnetoresistance. Herein, it is shown that PtTe2, PdTe2, and NiTe2 display high-speed terahertz (THz) detection capability at room temperature, which originates from their peculiar band structure with topologically protected electronic states. Furthermore, photodetectors based on their heterostructures are able to suppress dark current with high-performance detection of THz light. Furthermore, these crystals are stable in air and they can be easily exfoliated in nanosheets by liquid-phase exfoliation, due to the weak interlayer van der Waals bonds. The obtained results clearly establish that the type-II Dirac semimetals based on transition-metal ditellurides have immense research potential for addressing application-oriented issues for remote sensing and telecommunications. © 2021 The Authors. physica status solidi (RRL) Rapid Research Letters published by Wiley-VCH GmbH.

Texturing silicon wafers is one way to increase the performance of solar cells. This work is the first to report on the surface modification of Si wafers by processing in polytungstate melts. Scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction analysis (XRD), the Brunauer-Emmett-Teller (BET) method, and photoelectrochemical measurements were used to elucidate the effect of texturing conditions in the Na2WO4 - K2WO4 (1:1) melt containing 35 or 50 mol% WO3 at 973 K in air. As a result of cathodic treatment in the melt containing 50 mol% WO3 at the potential of -0.92 V (vs Pt) for 15 s, upright pyramids were formed on the Si surface. In addition, inverted pyramids appeared at the OTB/Si contact points. The photocurrent density of these samples was several times higher than that for the initial Si wafer or the Si wafer etched in 5 M NaOH solution at 353 K for 20 min. Mechanisms for the formation of upright and inverted pyramids were proposed. Unusual eight-faceted pyramids were formed on the Si surface during cathodic treatment in the melt containing 35 mol% WO3 at -1.19 V for 15 s, but the photocurrent density of such samples was low. © 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.

Two novel cycloplatinated complexes that differ by the presence/absence of a lateral fused cyclopenteno ring, respectively, were prepared. Although contributing to only a few percentage of the whole molecular volume, the presence of this aliphatic protuberance appears to be essential for the emergence of liquid crystalline behaviour. This pair of two similar compounds, non-mesomorphic complex and mesomorphic complex, was prepared as a model to assess the possible link of the self-aggregation in solution with the appearance of the liquid crystallinity in molten state. NMR dilution studies in CDCl3 solution and X-ray diffusion study in neat films show qualitative similarity of the aggregated structures formed by liquid crystalline complex. Solution studies may therefore be a useful additional tool to the characterization of the liquid crystalline properties and other self-association processes of Pt(II) complexes. © 2021

In this paper we report the geometries, properties, and reactivity descriptors of 12 structural isomers located on the MP2/SDDALL potential energy surface of the (1)Au(6)Pt binary clusters. A nonplanar, D(3d) symmetry, cyclohexane chairlike structure is predicted to be the global minimum. Binding energies per atom in the range approximately 44-51 kcal/mol account for very stable clusters. The relative stability of the clusters is directly related to all global and local reactivity descriptors. All structures are predicted to have large electron affinities. The chemical environment of the Pt atom on the structures plays a central role in the resulting relative stabilities and global and local reactivities. Our results show that more peripheral Pt atoms are more likely to be involved in electron-accepting processes.

Basal-like breast cancer is an incurable disease with limited therapeutic options, mainly due to the frequent development of anti-cancer drug resistance. Therefore, identification of druggable targets to improve current therapies and overcome these resistances is a major goal. Targeting DNA repair mechanisms has reached the clinical setting and several strategies, like the inhibition of the CHK1 kinase, are currently in clinical development. Here, using a panel of basal-like cancer cell lines, we explored the synergistic interactions of CHK1 inhibitors (rabusertib and SAR020106) with approved therapies in breast cancer and evaluated their potential to overcome resistance. We identified a synergistic action of these inhibitors with agents that produce DNA damage, like platinum compounds, gemcitabine, and the PARP inhibitor olaparib. Our results demonstrated that the combination of rabusertib with these chemotherapies also has a synergistic impact on tumor initiation, invasion capabilities, and apoptosis in vitro. We also revealed a biochemical effect on DNA damage and caspase-dependent apoptosis pathways through the phosphorylation of H2AX, the degradation of full-length PARP, and the increase of caspases 3 and 8 activity. This agent also demonstrated synergistic activity in a platinum-resistant cell line, inducing an increase in cell death in response to cisplatin only when combined with rabusertib, while no toxic effect was found on non-tumorigenic breast tissue-derived cell lines. Lastly, the combination of CHK1 inhibitor with cisplatin and gemcitabine resulted in more activity than single or double combinations, leading to a higher apoptotic effect. In conclusion, in our study we identify therapeutic options for the clinical development of CHK1 inhibitors, and confirm that the inhibition of this kinase can overcome acquired resistance to cisplatin.

Due to their physical properties and potential applications in energy conversion and storage, transition-metal dichalcogenides (TMDs) have garnered substantial interest in recent years. Among this class of materials, TMDs based on molybdenum, tungsten, sulfur, and selenium are particularly attractive due to their semiconducting properties and the availability of bottom-up synthesis techniques. Here we report a method which yields high-quality crystals of transition-metal diselenide and ditelluride compounds (PtTe2, PdTe2, NiTe2, TaTe2, TiTe2, RuTe2, PtSe2, PdSe2, NbSe2, TiSe2, VSe2, ReSe2) from their solid solutions, via vapor deposition from a metal-saturated chalcogen melt. Additionally, we show the synthesis of rare-earth-metal polychalcogenides and NbS2 crystals using the aforementioned process. Most of the crystals obtained have a layered CdI2 structure. We have investigated the physical properties of selected crystals and compared them to state of the art findings reported in the literature. Remarkably, the charge density wave transition in 1T-TiSe2 and 2H-NbSe2 crystals is well-defined at TCDW ≈ 200 and 33 K, respectively. Angle-resolved photoelectron spectroscopy and electron diffraction are used to directly access the electronic and crystal structures of PtTe2 single crystals and yield state of the art measurements. © 2020 American Chemical Society.

We have measured the two-dimensional image potential states (IPS) of a germanene layer synthesized on a Ge2Pt crystal using scanning tunnelling microscopy and spectroscopy. The IPS spectrum of germanene exhibits several differences as compared to the IPS spectrum of pristine Ge(001). First, the n = 1 peak of the Rydberg series of the IPS spectrum of germanene has two contributions, labelled n = 1- and n = 1+, respectively. The peak at the lower energy side is weaker and is associated to the mirror-symmetric state with opposite parity. The appearance of this peak indicates that the interaction between the germanene layer and the substrate is very weak. Second, the work function of germanene is about 0.75 eV lower in energy than the work function of Ge(001). This large difference in work function of germanene and pristine Ge(001) is in agreement with first-principles calculations. © 2020 The Author(s). Published by IOP Publishing Ltd.

The growth of ultrathin layers of VOx (< 12 monolayers) on Pt(111) and the activity of these layers in catalytic methanol oxidation at 10−4 mbar have been studied with low-energy electron diffraction, Auger electron spectroscopy, rate measurements, and with photoemission electron microscopy. Reactive deposition of V in O2 at 670 K obeys a Stranski–Krastanov growth mode with a (√3 × √3)R30° structure representing the limiting case for epitaxial growth of 3D-VOx. The activity of VOx/Pt(111) in catalytic methanol oxidation is very low and no redistribution dynamics is observed lifting the initial spatial homogeneity of the VOx layer. Under reaction conditions, part of the surface vanadium diffuses into the Pt subsurface region. Exposure to O2 causes part of the V to diffuse back to the surface, but only up to one monolayer of VOx can be stabilized in this way at 10−4 mbar.

PURPOSE A phase II study (ClinicalTrials.gov identifier: NCT00628251) showed activity of olaparib capsules versus pegylated liposomal doxorubicin in patients with germline BRCA-mutated platinum-resistant or partially platinum-sensitive relapsed ovarian cancer. We conducted a phase III trial (SOLO3) of olaparib tablets versus nonplatinum chemotherapy in patients with germline BRCA-mutated platinum-sensitive relapsed ovarian cancer who had received at least 2 prior lines of platinum-based chemotherapy. PATIENTS AND METHODS In this randomized, open-label trial, patients were randomly assigned 2:1 to olaparib 300 mg twice a day or physician’s choice single-agent nonplatinum chemotherapy (pegylated liposomal doxorubicin, paclitaxel, gemcitabine, or topotecan). The primary end point was objective response rate (ORR) in the measurable disease analysis set assessed by blinded independent central review (BICR). The key secondary end point was progression-free survival (PFS) assessed by BICR in the intent-to-treat population. RESULTS Of 266 randomly assigned patients, 178 were assigned to olaparib and 88 to chemotherapy. In patients with measurable disease (olaparib, n = 151; chemotherapy, n = 72), the BICR-assessed ORR was significantly higher with olaparib than with chemotherapy (72.2% v 51.4%; odds ratio [OR], 2.53 [95% CI, 1.40 to 4.58]; P = .002). In the subgroup who had received 2 prior lines of treatment, the ORR was 84.6% with olaparib and 61.5% with chemotherapy (OR, 3.44 [95% CI, 1.42 to 8.54]). BICR-assessed PFS also significantly favored olaparib versus chemotherapy (hazard ratio, 0.62 [95% CI, 0.43 to 0.91]; P = .013; median, 13.4 v 9.2 months). Adverse events were consistent with the established safety profiles of olaparib and chemotherapy. CONCLUSION Olaparib resulted in statistically significant and clinically relevant improvements in ORR and PFS compared with nonplatinum chemotherapy in patients with germline BRCA-mutated platinum-sensitive relapsed ovarian c

BackgroundChemotherapy-induced peripheral neuropathy (CIPN) is a significant and difficult to manage side effect of neurotoxic chemotherapies. Several risk factors for CIPN have been identified to date, but inconsistencies and methodological limitations exist in past research. Also, a limited number of potential risk factors has been investigated in the past.AimThe objective of this study was to assess the relative contribution of a wider range of risk factors in the development of CIPN.MethodsThis analysis used the 6-month data after starting chemotherapy from a larger prospective observational study on CIPN risk, prevalence, and quality of life. Patients were assessed at recruitment for possible CIPN risk factors, including prior history of neuropathies, current/past infectious diseases; neurotoxic medication history; personal and treatment characteristics; smoking history, alcohol use, and vegetable/fruit intake. Neuropathy was assessed at 6-months after starting chemotherapy with the neuropathy (motor/sensory) items of the NCI-CTCAE scale and the WHO criterion for neuropathy. Data on symptom burden were also collected.ResultsData were available from 255 patients from three cancer centers in Hong Kong, Singapore, and UK. The use of different scales did not always identify the same predictor variables. Key risk factors in multivariate regression models included older age (highest OR = 1.08, p < 0.01 with the WHO scale), chemotherapy (platinum-based chemotherapy had OR = 0.20-0.27 in developing CIPN compared to taxane-based chemotherapy), history of neuropathy (for motor CIPN only, OR = 8.36, p < 0.01), symptom burden (OR = 1.06, p < 0.05), number of chemotherapy cycles received (OR = 1.19-1.24, p < 0.01), and alcohol intake (OR = 0.32, p < 0.05). In univariate analysis, the use of statins was implicated with CIPN (p = 0.03-0.0

The light-emitting efficiency of luminescent materials is invariably compromised on moving to the red and near-infrared regions of the spectrum due to the transfer of electronic excited-state energy into vibrations. We describe how this undesirable "energy gap law" can be sidestepped for phosphorescent organometallic emitters through the design of a molecular emitter that incorporates two platinum(II) centers. The dinuclear cyclometallated complex of a substituted 4,6-bis(2-thienyl)pyrimidine emits very brightly in the red region of the spectrum (λ max = 610 nm, Î= 0.85 in deoxygenated CH 2 Cl 2 at 300 K). The lowest-energy absorption band is extraordinarily intense for a cyclometallated metal complex: At λ = 500 nm, Îμ = 53 800 M -1 cm -1 . The very high efficiency of emission achieved can be traced to an unusually high rate constant for the T 1 â†' S 0 phosphorescence process, allowing it to compete effectively with nonradiative vibrational decay. The high radiative rate constant correlates with an unusually large zero-field splitting of the triplet state, which is estimated to be 40 cm -1 by means of variableerature time-resolved spectroscopy over the range 1.7 < T < 120 K. The compound has been successfully tested as a red phosphor in an organic light-emitting diode prepared by solution processing. The results highlight a potentially attractive way to develop highly efficient red and NIR-emitting devices through the use of multinuclear complexes. © 2019 American Chemical Society.

As a result of the innovative solutions found due to the joint efforts of Russian and Finnish researchers, the recovery of nonferrous and precious metals in Norilsk Nickel Harjavalta was significantly increased (%): the recovery of Ni was increased to 98.7; that of Cu, to 99.5; Pt, to 99.6; and Pd to 99.6. Simultaneously, a copper cake (one of the main commercial products) of an improved composition, namely, (%) 57–62 Cu, <3 Ni, 8–11 Fe, was produced. The arsenic content in the copper cake was decreased from 1.5–2 to 0.15–0.3%. The largest projects are as follows: stage-by stage implementation of a matte-free technology with simultaneous modification of the matte line for processing converter matte; the development of a jarosite technology of iron deposition from a nickel solution, which decreased the irreversible losses of nonferrous and precious metals with a waste iron cake as much as possible (the losses of nickel and cobalt were decreased by 11 times; those of copper, by 23 times; platinum, by 16%; palladium, by 10%; rhodium, by 9%; gold, by 12%); and the building and introduction of carbonate processing, which allowed the production of nickel cathodes to be increased. As a result of the measures taken to redistribute raw materials, the mattes of slag-cleaning furnaces, which contained 35–40% Fe, were moved to KGMK. This integration solution led to a significant synergy effect in Nornickel. One of the key factors of the economic efficiency of the matte-free technology was a decrease in the specific consumption of the main reagents (oxygen, air, sulfuric acid) and the energy resources used for the manufacture of nickel products. As a result, the transaction costs were decreased by ~3.5 mln dollars per year. © 2019, Pleiades Publishing, Ltd.

ObjectiveTo analyze clinical prognostic factors for survival after recurrence of high-grade, advanced-stage ovarian-peritoneal-tubal carcinoma and to develop a nomogram to predict individual survival after recurrence.MethodsWe retrospectively analyzed patients treated in multicenter Gynecologic Oncology Group protocols for stage III and IV ovarian-peritoneal-tubal carcinoma who underwent primary debulking surgery, received chemotherapy with paclitaxel and a platinum compound, and subsequently developed recurrence. Prognostic factors affecting survival were identified and used to develop a nomogram, which was both internally and externally validated.ResultsThere were 4,739 patients included in this analysis, of whom, 84% had stage III and 16% had stage IV ovarian carcinoma. At a median follow-up of 88.8 months (95% CI 86.2-92.0 months), the vast majority of patients (89.4%) had died. The median survival after recurrence was 21.4 months (95% CI 20.5-21.9 months). Time to recurrence after initial chemotherapy, clear cell or mucinous histology, performance status, stage IV disease, and age were significant variables used to develop a nomogram for survival after recurrence, which had a concordance index of 0.67. The time to recurrence alone accounted for 85% of the prognostic information. Similar results were found for patients who underwent second look laparotomy and had a complete pathologic response or received intraperitoneal chemotherapy.ConclusionFor individuals with advanced-stage ovarian carcinoma who recur after standard first-line therapy, estimated survivals after recurrence are closely related to the time to recurrence after chemotherapy and prognostic variables can be used to predict subsequent survival.Clinical trial registrationClinialTrials.gov, NCT00002568, NCT00837993, NCT00002717, NCT01074398, and NCT00011986.

OBJECTIVE: To analyze clinical prognostic factors for survival after recurrence of high-grade, advanced-stage ovarian-peritoneal-tubal carcinoma and to develop a nomogram to predict individual survival after recurrence. METHODS: We retrospectively analyzed patients treated in multicenter Gynecologic Oncology Group protocols for stage III and IV ovarian-peritoneal-tubal carcinoma who underwent primary debulking surgery, received chemotherapy with paclitaxel and a platinum compound, and subsequently developed recurrence. Prognostic factors affecting survival were identified and used to develop a nomogram, which was both internally and externally validated. RESULTS: There were 4,739 patients included in this analysis, of whom, 84% had stage III and 16% had stage IV ovarian carcinoma. At a median follow-up of 88.8 months (95% CI 86.2-92.0 months), the vast majority of patients (89.4%) had died. The median survival after recurrence was 21.4 months (95% CI 20.5-21.9 months). Time to recurrence after initial chemotherapy, clear cell or mucinous histology, performance status, stage IV disease, and age were significant variables used to develop a nomogram for survival after recurrence, which had a concordance index of 0.67. The time to recurrence alone accounted for 85% of the prognostic information. Similar results were found for patients who underwent second look laparotomy and had a complete pathologic response or received intraperitoneal chemotherapy. CONCLUSION: For individuals with advanced-stage ovarian carcinoma who recur after standard first-line therapy, estimated survivals after recurrence are closely related to the time to recurrence after chemotherapy and prognostic variables can be used to predict subsequent survival. CLINICAL TRIAL REGISTRATION: ClinialTrials.gov, NCT00002568, NCT00837993, NCT00002717, NCT01074398, and NCT00011986.

Platinum thin films activated ex situ by oxygen plasma become reduced by the combined effect of an intense soft X-ray photon beam and condensed water. The evolution of the electronic structure of the surface has been characterized by near-ambient-pressure photoemission and mimics the inverse two-step sequence observed in the electro-oxidation of platinum, i.e. the surface-oxidized platinum species are reduced first and then the adsorbed species desorb in a second step leading to a surface dominated by metallic platinum. The comparison with measurements performed under high-vacuum conditions suggests that the reduction process is mainly induced by the reactive species generated by the radiolysis of water. When the photon flux is decreased, then the reduction process becomes slower., Postprint (author's final draft)

PtTe2 is a novel transition-metal dichalcogenide hosting type-II Dirac fermions that displays application capabilities in optoelectronics and hydrogen evolution reaction. Here it is shown, by combining surface science experiments and density functional theory, that the pristine surface of PtTe2 is chemically inert toward the most common ambient gases (oxygen and water) and even in air. It is demonstrated that the creation of Te vacancies leads to the appearance of tellurium-oxide phases upon exposing defected PtTe2 surfaces to oxygen or ambient atmosphere, which is detrimental for the ambient stability of uncapped PtTe2-based devices. On the contrary, in PtTe2 surfaces modified by the joint presence of Te vacancies and substitutional carbon atoms, the stable adsorption of hydroxyl groups is observed, an essential step for water splitting and the water–gas shift reaction. These results thus pave the way toward the exploitation of this class of Dirac materials in catalysis. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

CONTEXT:The most common adverse effects from neurotoxic chemotherapy are chemotherapy-induced neuropathy (CIPN), hearing loss, and tinnitus. Although associations between perceived stress and persistent pain, hearing loss, and tinnitus are documented, no studies have examined these associations in cancer survivors who received neurotoxic chemotherapy. OBJECTIVES:In this cross-sectional study, we evaluated for associations between perceived stress and the occurrence of CIPN, hearing loss, and tinnitus, in 623 adult cancer survivors who received platinum and/or taxane compounds. METHODS:Survivors completed self-report measures of hearing loss, tinnitus, and perceived stress (i.e., Impact of Events Scale-Revised [IES-R]). Separate logistic regression analyses were done for each neurotoxicity to evaluate whether each of the IES-R subscale (i.e., intrusion, avoidance, hyperarousal) and total scores made a significant independent contribution to neurotoxicity group membership. RESULTS:Of the 623 survivors in this study, 68.4% had CIPN, 34.5% reported hearing loss, and 31.0% reported tinnitus. Older age, higher body mass index, poorer functional status, being born prematurely, cancer diagnosis, and higher intrusion (P = 0.013), hyperarousal (P = 0.014), and total (P = 0.047) IES-R scores were associated with CIPN. Older age, being male, poorer functional status, a worse comorbidity profile, and a higher IES-R hyperarousal (P = 0.007) score were associated with hearing loss. Being male, having less education, a worse comorbidity profile, and a higher IES-R hyperarousal (P = 0.029) score were associated with tinnitus. CONCLUSION:These findings suggest that increased levels of perceived stress are associated with the most common chemotherapy-induced neurotoxicities.

IntroductionCytotoxic chemotherapy might prime urothelial cancer (UC) to checkpoint inhibition, prompting a trial of chemotherapy with the programmed death receptor-1 inhibitor pembrolizumab.Patients and methodsPatients with advanced, platinum-refractory UC received pembrolizumab and either docetaxel (arm A) or gemcitabine (arm B). Primary end points were assessments of maximum tolerated dose and dose-limiting toxicity (DLT). Secondary end points were overall response rate (ORR) and progression-free survival (PFS).ResultsTwelve patients were enrolled in the initial cohorts; 6 in each arm. One DLT was seen in each arm: Grade 3 hypophosphatemia (arm A), Grade 3 diarrhea (arm B). Adverse events of Grade >3 were observed in 7 (54%), the most common being anemia (6; 50%), fatigue (6; 50%), hyponatremia (4; 33%) and neutropenia (3; 25%), with no treatment-related deaths. There were 5 confirmed responses (1 complete, 4 partial), with an ORR of 42% and disease control rate (DCR) of 58%. Arm A had an ORR of 50% and DCR of 67%, whereas arm B had an ORR of 33% and DCR of 50%. Median PFS was 4.8, 5.7, and 3.7 months for the overall cohort, arm A, and arm B, respectively.ConclusionPembrolizumab with either docetaxel or gemcitabine is feasible for treatment of platinum-refractory advanced UC patients. Preliminary efficacy was observed. Further examination is warranted.

Pathogenic mutations in two autosomal dominant genes, BRCA1 and BRCA2, with high penetrance are supposed to be the cause for an approximated 5-7% risk of all breast cancer (BC) and ovarian cancer (OC). Compared to sporadic BC, BRCA mutated (BRCAmut) BC differs for lifetime risk of onset and sensitivity to systemic therapies. A hereditary BC syndrome should be taken into account when there are numerous relatives with BC early-onset (typically before menopause). Moreover, BRCAmut carriers showed a lifetime possibility of manifesting OC. When a BC diagnosis is made in young patients or in suspicious personal relatives' anamnesis, be aware of being carriers of a BRCA mutation may influence the decision making-process about surgical procedure and prevention strategies. In this review, we examined surgical treatment choice for BRCAmut BC, risk of ipsilateral breast recurrence (IBR) and contralateral breast cancer (CBC). We examined the role of breast-conserving therapy (BCT), risk-reducing mastectomy (RRM) and preventive risk-reducing salpingo-oophorectomy (RRSO) with a special consideration about advantage in terms of mortality reduction for both conservative and prophylactic measures. We also reviewed the sensitivity of mutated BC to platinum-based antineoplastic drugs and poly (ADP-ribose) polymerase inhibitors (PARPi) by emphasizing the results of clinical trials recently published.

BackgroundAvelumab, a human Ig-G1 monoclonal antibody targeting PD-L1 and approved in the USA for the treatment of metastatic Merkel cell carcinoma, has shown antitumour activity and an acceptable safety profile in patients with advanced solid tumours in a dose-escalation phase 1a trial. In this dose-expansion cohort of that trial, we assess avelumab treatment in a cohort of patients with advanced, platinum-treated non-small-cell lung cancer (NSCLC).MethodsIn this dose-expansion cohort of a multicentre, open-label, phase 1 study, patients with progressive or platinum-resistant metastatic or recurrent NSCLC were enrolled at 58 cancer treatment centres and academic hospitals in the USA. Eligible patients had confirmed stage IIIB or IV NSCLC with squamous or non-squamous histology, measurable disease by Response Evaluation Criteria In Solid Tumors version 1.1 (RECIST v1.1), tumour biopsy or archival sample for biomarker assessment, and Eastern Cooperative Oncology Group performance status 0 or 1, among other criteria. Patient selection was not based on PD-L1 expression or expression of other biomarkers, including EGFR or KRAS mutation or ALK translocation status. Patients received infusional avelumab monotherapy 10 mg/kg every 2 weeks until disease progression or toxicity. The primary objective was to assess safety and tolerability. This trial is registered with ClinicalTrials.gov, number NCT01772004; enrolment in this cohort is closed and the trial is ongoing.FindingsBetween Sept 10, 2013, and June 24, 2014, 184 patients were enrolled and initiated treatment with avelumab. Median follow-up duration was 8·8 months (IQR 7·2-11·9). The most common treatment-related adverse events of any grade were fatigue (46 [25%] of 184 patients), infusion-related reaction (38 [21%]), and nausea (23 [13%]). Grade 3 or worse treatment-related adverse events occurred in 23 (13%) of 184 patients; the most common (occurring in more than two patients) were infusion-related reaction (four [2

CONTEXT: Evidence suggests that chemotherapy-induced neuropathy (CIN) is a significant problem for cancer survivors. However, a detailed phenotypic characterization of CIN in cancer survivors is not available. OBJECTIVES: To evaluate between-group differences in demographic and clinical characteristics, as well as in measures of sensation, function, and postural control, in a sample of cancer survivors who received a platinum and/or a taxane-based CTX regimen and did (n = 426) and did not (n = 197) develop CIN. METHODS: Survivors completed self-report questionnaires and underwent objective testing (i.e., light touch, pain sensation, cold sensation, vibration, muscle strength, grip strength, Purdue Pegboard test, Timed Get Up and Go test, Fullerton Advanced Balance test). Parametric and nonparametric statistics were used to compare between-group differences in study outcomes. RESULTS: Of the 426 survivors with CIN, 4.9% had CIN only in their upper extremities, 27.0% only in their lower extremities, and 68.1% in both their upper and lower extremities. Demographic and clinical characteristics associated with CIN included the following: older age, lower annual income, higher body mass index, a higher level of comorbidity, being born prematurely, receipt of a higher cumulative dose of chemotherapy, and a poorer functional status. Survivors with CIN had worse outcomes for all of the following objective measures: light touch, pain, temperature, vibration, upper and lower extremity function, and balance. CONCLUSIONS: This study is the first to provide a detailed phenotypic characterization of CIN in cancer survivors who received a platinum and/or a taxane compound. These data can serve as a benchmark for future studies of CIN in cancer survivors.

Purpose There are no approved treatments for recurrent/metastatic head and neck squamous cell carcinoma refractory to platinum and cetuximab. In the single-arm, phase II KEYNOTE-055 study, we evaluated pembrolizumab, an anti-programmed death 1 receptor antibody, in this platinum- and cetuximab-pretreated population with poor prognosis. Methods Eligibility stipulated disease progression within 6 months of platinum and cetuximab treatment. Patients received pembrolizumab 200 mg every 3 weeks. Imaging was performed every 6 to 9 weeks. Primary end points: overall response rate (Response Evaluation Criteria in Solid Tumors v1.1, central review) and safety. Efficacy was assessed in all dosed patients and in subgroups on the basis of programmed death ligand 1 (PD-L1) expression and human papillomavirus (HPV) status. Results Among 171 patients treated, 75% received two or more prior lines of therapy for metastatic disease, 82% were PD-L1 positive, and 22% were HPV positive. At the time of analysis, 109 patients (64%) experienced a treatment-related adverse event; 26 patients (15%) experienced a grade ≥ 3 event. Seven patients (4%) discontinued treatment, and one died of treatment-related adverse events. Overall response rate was 16% (95% CI, 11% to 23%), with a median duration of response of 8 months (range, 2+ to 12+ months); 75% of responses were ongoing at the time of analysis. Response rates were similar in all HPV and PD-L1 subgroups. Median progression-free survival was 2.1 months, and median overall survival was 8 months. Conclusion Pembrolizumab exhibited clinically meaningful antitumor activity and an acceptable safety profile in recurrent/metastatic head and neck squamous cell carcinoma previously treated with platinum and cetuximab.

BackgroundOverall response rate is frequently used as an end point in phase 2 trials of platinum-treated extensive stage (ES) small-cell lung cancer (SCLC). We hypothesized that disease control rate (DCR) would be a superior surrogate for subsequent survival outcomes.MethodsUpdated patient-level data from Southwest Oncology Group (SWOG) trials in second- and/or third-line ES-SCLC patients were pooled. Landmark analysis was performed among patients alive at 8 weeks for overall survival (OS) measured from the 8-week landmark. Association of clinical prognostic factors with DCR was assessed using logistic regression. A Cox proportional hazard model was used to assess the associations between DCR at the landmark time and subsequent OS, adjusted for prognostic factors.ResultsOf the 319 ES-SCLC patients, 263 were alive at the 8-week landmark and constituted the pooled study population. Only 8 patients had a response. Disease control at 8 weeks was seen in 98 patients. Bivariate analysis of OS from the 8-week landmark revealed that DCR (hazard ratio [HR], 0.47; P < .0001) and elevated lactate dehydrogenase (HR, 1.70; P = .0004) were significantly associated with OS. In multivariable analysis, DCR remained an independent predictor of subsequent survival from the 8-week landmark (HR, 0.50; P < .0001).ConclusionIn this large second- and third-line ES-SCLC database, DCR at 8 weeks was found to be a significant predictor of subsequent survival in patients receiving investigational therapy. These results have critical implications in the selection of surrogate end points in future prospective ES-SCLC trials.

Background: The anti-tumour activity of cisplatin is thought to be a result of its capacity to form DNA adducts which prevent cellular processes such as DNA replication and transcription. These DNA adducts can effectively induce cancer cell death, however, there are a range of clinical side effects and drug resistance issues associated with its use. In this study, the biological properties of three novel dinuclear platinum-based compounds (that contain alkane bridging linkers of eight, ten and twelve carbon atoms in length) were characterised to assess their potential as anticancer agents. Methods: The properties of these compounds were determined using a DNA template containing seven tandem telomeric repeat sequences. A linear amplification reaction was used in combination with capillary electrophoresis to quantify the sequence specificity of DNA adducts formed by these compounds at base pair resolution. The DNA cross-linking ability of these compounds was assessed using denaturing agarose gel electrophoresis and cytotoxicity was determined in HeLa cells using a colorimetric cell viability assay. Results: The dinuclear compounds were found to preferentially form DNA adducts at guanine bases and they exhibited different damage intensity profiles at the telomeric repeat sequences compared to that of cisplatin. The dinuclear compounds were found to exhibit a low level of cytotoxicity relative to cisplatin and their cytotoxicity increased as the linker length increased. Conversely, the interstrand cross-linking efficiency of the dinuclear compounds increased as the linker length decreased and the compound with the shortest alkane linker was six-fold more effective than cisplatin. Conclusions: Since the bifunctional compounds exhibit variation in sequence specificity of adduct formation and a greater ability to cross-link DNA relative to cisplatin they warrant further investigation towards the goal of developing new cancer chemotherapeutic agents.

The development of anticancer drug delivery systems which retain or enhance the cytotoxic properties of the drug to tumorous tissues, while reducing toxicity to other organs is of key importance. We investigated different poly(methacrylic acid)-g-poly(ethyleneglycol methacrylate) polymers as in situ coating agents for magnetite nanocrystallites. The obtained magnetic nano-assemblies were in turn thoroughly characterized for their structural, colloidal and physicochemical properties (drug loading capacity/release, magnetic field triggered drug release, cell uptake and localization) in order to select the best performing system. With the focus on in vivo validation of such magnetic drug delivery systems for first time, we selected cisplatin as the drug, since it is a potent anticancer agent which exhibits serious side effects due to lack of selectivity. In addition, cisplatin would offer facile determination of the metal content in the animal tissues for biodistribution studies. Alongside post-mortem Pt determination in the tissues, the biodistribution of the drug nanocarriers was also monitored in real time with PET-CT (positron emission tomography/computed tomography) with and without the presence of magnetic field gradients; using a novel chelator-free method, the nanoparticles were radiolabeled with 68Ga without having to alter their structure with chemical modifications for conjugation of radiochelators. The ability to be radiolabeled in such a straightforward but very robust way, along with their measured high MRI response, renders them attractive for dual imaging, which is an important functionality for translational investigations. Their anticancer properties were evaluated in vitro and in vivo, in a cisplatin resistant HT-29 human colon adenocarcinoma model, with and without the presence of magnetic field gradients. Enhanced anticancer efficacy and reduced toxicity was recorded for the cisplatin-loaded nanocarriers in comparison to the free cisplatin, particu

PurposeHallmarks of germline BRCA1/2-associated ovarian carcinomas include chemosensitivity and improved survival. The therapeutic impact of somatic BRCA1/2 mutations and mutations in other homologous recombination DNA repair genes is uncertain.Experimental designUsing targeted capture and massively parallel genomic sequencing, we assessed 390 ovarian carcinomas for germline and somatic loss-of-function mutations in 30 genes, including BRCA1, BRCA2, and 11 other genes in the homologous recombination pathway.ResultsThirty-one percent of ovarian carcinomas had a deleterious germline (24%) and/or somatic (9%) mutation in one or more of the 13 homologous recombination genes: BRCA1, BRCA2, ATM, BARD1, BRIP1, CHEK1, CHEK2, FAM175A, MRE11A, NBN, PALB2, RAD51C, and RAD51D. Nonserous ovarian carcinomas had similar rates of homologous recombination mutations to serous carcinomas (28% vs. 31%, P = 0.6), including clear cell, endometrioid, and carcinosarcoma. The presence of germline and somatic homologous recombination mutations was highly predictive of primary platinum sensitivity (P = 0.0002) and improved overall survival (P = 0.0006), with a median overall survival of 66 months in germline homologous recombination mutation carriers, 59 months in cases with a somatic homologous recombination mutation, and 41 months for cases without a homologous recombination mutation.ConclusionsGermline or somatic mutations in homologous recombination genes are present in almost one third of ovarian carcinomas, including both serous and nonserous histologies. Somatic BRCA1/2 mutations and mutations in other homologous recombination genes have a similar positive impact on overall survival and platinum responsiveness as germline BRCA1/2 mutations. The similar rate of homologous recombination mutations in nonserous carcinomas supports their inclusion in PARP inhibitor clinical trials.

Platinum compounds display clinical activity against a wide variety of solid tumors; however, resistance to these agents is a major limitation in cancer therapy. Reduced platinum uptake and increased platinum export are examples of resistance mechanisms that limit the extent of DNA damage. Here, we report the discovery and characterization of the role of ATP11B, a P-type ATPase membrane protein, in cisplatin resistance. We found that ATP11B expression was correlated with higher tumor grade in human ovarian cancer samples and with cisplatin resistance in human ovarian cancer cell lines. ATP11B gene silencing restored the sensitivity of ovarian cancer cell lines to cisplatin in vitro. Combined therapy of cisplatin and ATP11B-targeted siRNA significantly decreased cancer growth in mice bearing ovarian tumors derived from cisplatin-sensitive and -resistant cells. In vitro mechanistic studies on cellular platinum content and cisplatin efflux kinetics indicated that ATP11B enhances the export of cisplatin from cells. The colocalization of ATP11B with fluorescent cisplatin and with vesicular trafficking proteins, such as syntaxin-6 (STX6) and vesicular-associated membrane protein 4 (VAMP4), strongly suggests that ATP11B contributes to secretory vesicular transport of cisplatin from Golgi to plasma membrane. In conclusion, inhibition of ATP11B expression could serve as a therapeutic strategy to overcome cisplatin resistance., Published in the Journal of Clinical Investigation, v123 n5 p2119-2130, May 2013. Sponsored in part by NIH, and additional DoD grant BC085265. Prepared in cooperation with the Department of Gynecologic Oncology, the Center for RNA Interference and Non-coding RNA, the Department of Cancer Biology, the Department of Systems Biology, and the Department of Experimental Therapeutics at the University of Texas MD Anderson Cancer Center, Houston, TX, the Department of Medicine, Columbia University, New York, NY, the Department of Biochemistry and Cancer Center, Medical Sciences Campus, University of Puerto Rico, San Juan, the Department of Microbiology, University of Iowa, Iowa City, the Department of Biochemistry and Molecular Biology, Penn State University, University Park, and the Children s Memorial Research Center, Northwestern University Feinberg School of Medicine, Chicago, IL.

ObjectiveHistologic subtyping has been advocated to select chemotherapy for patients with advanced-stage non-small-cell lung cancer (NSCLC). To determine whether histologic subtype was associated with efficacy for the commonly used antimicrotubule (AMT) agents, paclitaxel, docetaxel, and vinorelbine plus a platinum compound, we examined the Southwest Oncology Group (SWOG) lung cancer database.MethodsData from 4 randomized trials (S9308, S9509, S9806, and S0003) administering an AMT agent plus platinum in patients receiving first-line treatment for advanced-stage NSCLC were analyzed. Overall survival (OS) and progression-free survival (PFS) comparisons were performed using Cox proportional hazard regression, adjusting for sex. Median survival times were estimated by Kaplan-Meier.ResultsOf 1146 patients included in this analysis, 640 had adenocarcinoma (56%), 220 had squamous cell carcinoma (19%), 121 had large cell carcinoma (11%), and 165 had NSCLC not otherwise specified (NOS) (14%). Median OS times by histologic subtypes were 8.5, 8.4, 8.2, and 9.6 months, respectively, and median PFS times were 4.2, 4.3, 4.3, and 4.6 months, respectively. No difference in OS or PFS was observed by histologic subtype and, specifically, between nonsquamous and squamous histologies.ConclusionsThis pooled analysis from 4 SWOG trials using an AMT-platinum regimen did not show a difference in survival outcomes by histologic subtype. Because the majority of patients with advanced NSCLC continue to receive chemotherapy, defining molecular-based predictive markers of responsiveness is warranted.

The aim of this multicenter, retrospective study was to evaluate the efficacy and the safety of single agent Trabectedin (ET-743, Yondelis) in very heavily treated, relapsed ovarian cancer (ROC) patients.

In this brief report we have described eight children affected by optic pathway/hypothalamus gliomas and treated with carboplatin and/or cisplatin, which developed a derangement of sodium and water metabolism, due to diabetes insipidus (DI) or to syndrome of inappropriate antidiuretic hormone secretion (SIADH) after surgical resection. In four out of these eight patients the treatment with platinum compounds produced prolonged haematological toxicity and in five out of them it caused neurosensorial bilateral hypoacusia. In addition cisplatin worsened electrolytes disturbances. Hence children with DI or SIADH should be carefully monitored before, during and after the treatment with platinum compounds.

Platinum compounds are widely used in the treatment of pediatric tumors such as neuroblastoma, germ-cell tumors, osteosarcoma, retinoblastoma, hepatoblastoma, brain tumors (low-grade gliomas and medulloblastoma/PNET), and relapsed and refractory lymphomas. The three major platinum compounds (cisplatin, carboplatin, and oxaliplatin) have a similar pharmacokinetics profile and mechanism of action, but the differences in their chemical structure are responsible for their different antitumor activity and toxicity. In this review, we have described the main characteristics of cisplatin, carboplatin, and oxaliplatin, focusing on their toxic effects and possible strategies to prevent them to improve the clinical outcomes in pediatric cancer patients. The underlying mechanism of each platinum-related toxicity is shown together with the clinical manifestations. Furthermore, possible preventive strategies are suggested to reduce the negative impact of platinum compounds on the quality of life of children with cancer. Cisplatin seems to be mostly ototoxic and nephrotoxic, carboplatin mainly produces myelosuppression, whereas oxaliplatin induces predominantly peripheral sensory neurotoxicity. In contrast, nausea and vomiting can be linked to all platinum compounds, although cisplatin exerts the strongest emetic effect. A correct knowledge of pharmacokinetics and toxicological profile of platinum compounds may aid physicians prevent their toxicity on auditory, nervous, renal, and bone marrow function, improving the quality of life of pediatric cancer patients.

PURPOSE OF REVIEW: After multimodal treatment, 50-60% of patients with locally advanced squamous cell carcinoma of the head and neck will present locoregional and/or distant relapse within 2 years. This article will review chemotherapy and/or targeted agents as treatment options for patients who progress after platinum-based chemotherapy. RECENT FINDINGS: After years when the only therapeutic option was palliative chemotherapy, monoclonal antibodies targeting the epidermal growth factor receptor have emerged as new treatments. In particular, cetuximab and panitumumab have demonstrated progression-free survival and/or overall survival benefits in the first-line palliative treatment when given in combination with platinum-based chemotherapy. Recently, second-generation compounds (zalutumumab) or irreversible pan-human epidermal receptor (pan-HER) inhibitors have also shown promising activity after platinum failure. SUMMARY: Because median overall survival after platinum failure is less than 1 year, there is a clear requirement for new phase II/III studies with agents that have the potential to improve overall survival and quality of life. The previous use of platinum-based chemotherapy and the type of tumor response observed may substantially impact prognosis. Therefore, prior platinum use should be clearly defined in future clinical trials to enable a more accurate interpretation of the data.

The present study aimed to evaluate the new water soluble camptothecin analogue Namitecan (ST1968) in preclinical paediatric tumour models of the nervous system comprehensive of neuroblastoma, primitive neuroectodermal tumours/PNET and medulloblastoma where the drug was compared to Irinotecan.

The sub-nanometer beam of a helium ion microscope was used to study and optimize helium-ion beam induced deposition of PtC nanopillars with the (CH3)3Pt(CPCH3) precursor. The beam current, beam dwell time, precursor refresh time, and beam focus have been independently varied. Continuous beam exposure resulted in narrow but short pillars, while pulsed exposure resulted in thinner and higher ones. Furthermore, at short dwell times the deposition efficiency was very high, especially for a defocused beam. Efficiencies were measured up to 20 times the value for continuous exposure conditions. The interpretation of the experimental data was aided by a Monte Carlo simulation of the deposition. The results indicate that two regimes are operational in ion beam induced deposition (IBID). In the first one, the adsorbed precursor molecules originally present in the beam interaction region decompose. After the original precursor layer is consumed, further depletion is averted and growth continues by the supply of molecules via adsorption and surface diffusion. Depletion around the beam impact site can be distinguished from depletion on the flanges of the growing pillars. The Monte Carlo simulations for low precursor surface coverage reproduce measured growth rates, but predict considerably narrower pillars, especially at short dwell times. Both the experiments and the simulations show that the pillar width rapidly increases with increasing beam diameter. Optimal writing strategy, good beam focusing, and rapid beam positioning are needed for efficient and precise fabrication of extended and complex nanostructures by He-IBID., QN/Quantum Nanoscience, Applied Sciences

Epitaxial Ni(Pt)Si2-y (y < 1) films readily grow upon thermal treatment of 2 nm thick Ni and Ni0.96Pt0.04 films deposited on Si(001). For annealing at 500 degrees C, the films are 5.4-5.6 nm thick with 61-70 mu cm in resistivity. At 750 degrees C, the epitaxial Ni(Pt)Si2-y films become 6.1-6.2 nm thick with a resistivity of 42-44 mu cm. Structural analysis reveals twins, facet wedges, and thickness inhomogeneities in the films grown at 500 degrees C. For higher temperature, an almost defect-free NiSi2-y film with a flat and sharp interface is formed. The presence of Pt makes the aforementioned imperfections more persistent.

Aim: Cisplatin is the first platinum drug that shows promising anti-tumor effect clinically. Oxaliplatin, a third-generation platinum drug that incorporates a diaminocyclohexane (DACH) structural entity, can overcome cisplatin resistance. R,R-5, a novel platinum compound that integrates the DACH entity with a demethylcantharidin (DMC) component that is derived from a traditional Chinese medicine (TCM) , can also overcome cisplatin resistance. The principal objectives of this study was to investigate in detail, the effect of these compounds at the antephase and G2 checkpoints of the cell cycle, and to establish the relationship (if any) between different structural entities with checkpoint activation. The ultimate aim of the study was to ascertain the potential for the development of novel checkpoint abrogators as anti-tumor agents., Background: A common procedure in current cancer chemotherapy is to induce genomic stress in cancer cells, leading to irreparable DNA damage and eventually cell death. However, there are several DNA repair mechanisms in cancer cells to maintain genomic stability, which require cell cycle checkpoints to stop cell proliferation for DNA damage repair, thereby avoiding errors in cellular events like DNA replication, transcription and mitosis. Among these cell cycle checkpoints, antephase and G2 checkpoints are two gate checkpoints for mitosis. Abrogation of G2 checkpoint has been reported to give rise to synergistic cytotoxic effect with DNA damaging agents, representing a means of circumventing drug resistance in chemotherapy., Conclusions: Acute stress to cisplatin can activate the MMR/c-Abl/MEKK1/p38MAPK pathway, leading to the activation of antephase checkpoint, and stop cells from entering mitosis immediately. DACH-containing platinum compound oxaliplatin fails to activate this antephase checkpoint. However, both cisplatin and oxaliplatin can activate the G2 checkpoint, which can be abrogated by DMC. In contrast, RR-5 can bypass both the antephase and G2 checkpoints. In summary, novel TCM-platinum compound R,R-5 can bypass mitotic DNA damage checkpoints in cancer cells and thus has the potential for further development as an anti-cancer drug., Methods: Microarray analysis was used to detect gene transcription profiles after drug treatments. The activation of mitotic checkpoints was inspected by counting mitotic cells and utilizing flow cytometry. Using Western blotting, the activation of certain key players in the antephase and G2 checkpoint was revealed. MTT assays were performed to show the outcome of checkpoint activation., Results: In HCT116 cells, 35 genes that facilitate G2/M transition were found to be up-regulated after R,R-5 treatment compared with oxaliplatin in the microarray analysis, implying the bypass of mitotic checkpoints by R,R-5 rather than oxaliplatin. Acute stress (2 hour) of cisplatin activated the antephase checkpoint, resulting in a rapid decrease in mitotic index and phosphorylation of histone H1, which avoided mitotic catastrophe and promoted cell survival in HeLa cells. Further experiments demonstrated that this antephase checkpoint could be abrogated by c-Abl and p38MAPK inhibitors, or siRNAs against c-Abl or MEKK1, suggesting that this checkpoint may be controlled by an MMR/c-Abl/MEKK1/p38MAPK pathway. In contrast, oxaliplatin and R,R-5 did not activate this antephase checkpoint. Moreover, after 24 hour oxaliplatin treatment in HeLa cells, the mitotic index and CDK1 activity were decreased, which could be restored by concomitant treatment with ATM/ATR inhibitor and DMC. This indicated the activation of G2 checkpoint by oxaliplatin and implied that DMC can abrogate oxaliplatin-activated G2 checkpoint by restoring CDK1 activity. Cisplatin could also activate G2 checkpoint, whereas R,R-5 apparently bypassed this G2 checkpoint., Guan, Huaji., Adviser: Vincent Hon Leung Lee., Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: ., Thesis (Ph.D.)--Chinese University of Hong Kong, 2010., Includes bibliographical references (leaves 212-249)., Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web., Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web., also in Chinese., isbn: 9781124494234, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)