Reduced induction of human ß-defensins is involved in the pathological mechanism of cutaneous adverse effects caused by epidermal growth factor receptor monoclonal antibodies.

Epidermal growth factor receptor inhibitors (EGFRIs) frequently cause cutaneous adverse effects such as papulopustular eruptions. However, the mechanism of the reactions remains unclear. To assess the pathological mechanism of cutaneous adverse reactions caused by EGFRIs, we investigated whether EGFRIs have an influence on the innate immune response of the skin. Levels of human ß-defensins (hBDs), which serve as the first line of defence against infection by pathogenic microorganisms, in the stratum corneum samples of patients treated with EGFR. monoclonal antibodies were measured before and after starting therapy. There were no obvious trends in hBD production in patients without eruptions, whereas a significant decrease in hBD1 and hBD3 production and a nonsignficant decrease in hBD2 production were observed in patients who developed papulopustular eruptions. Our results suggest that a reduction in hBD contributes to the increased incidence of papulopustular eruptions.

Efficacy and safety of rebamipide liquid for chemoradiotherapy-induced oral mucositis in patients with head and neck cancer: a multicenter, randomized, double-blind, placebo-controlled, parallel-group phase II study.

BACKGROUND: Recent preclinical and phase I studies have reported that rebamipide decreased the severity of chemoradiotherapy-induced oral mucositis in patients with oral cancer. This placebo-controlled randomized phase II study assessed the clinical benefit of rebamipide in reducing the incidence of severe chemoradiotherapy-induced oral mucositis in patients with head and neck cancer (HNC). METHODS: Patients aged 20-75 years with HNC who were scheduled to receive chemoradiotherapy were enrolled. Patients were randomized to receive rebamipide 2% liquid, rebamipide 4% liquid, or placebo. The primary endpoint was the incidence of grade ≥ 3 oral mucositis determined by clinical examination and assessed by central review according to the Common Terminology Criteria of Adverse Events version 3.0. Secondary endpoints were the time to onset of grade ≥ 3 oral mucositis and the incidence of functional impairment (grade ≥ 3) based on the evaluation by the Oral Mucositis Evaluation Committee. RESULTS: From April 2014 to August 2015, 97 patients with HNC were enrolled, of whom 94 received treatment. The incidence of grade ≥ 3 oral mucositis was 29% and 25% in the rebamipide 2% and 4% groups, respectively, compared with 39% in the placebo group. The proportion of patients who did not develop grade ≥ 3 oral mucositis by day 50 of treatment was 57.9% in the placebo group, whereas the proportion was 68.0% in the rebamipide 2% group and 71.3% in the rebamipide 4% group. The incidences of adverse events potentially related to the study drug were 16%, 26%, and 13% in the placebo, rebamipide 2%, and rebamipide 4% groups, respectively. There was no significant difference in treatment compliance among the groups. CONCLUSIONS: The present phase II study suggests that mouth washing with rebamipide may be effective and safe for patients with HNC receiving chemoradiotherapy, and 4% liquid is the optimal dose of rebamipide. TRIAL REGISTRATION: ClinicalTrials.gov under the identifier NCT02085460 (the date of trial registration: March 11, 2014).

A yeast protein similar to bacterial two-component regulators.

Many bacterial signaling pathways involve a two-component design. In these pathways, a sensor kinase, when activated by a signal, phosphorylates its own histidine, which then serves as a phosphoryl donor to an aspartate in a response regulator protein. The Sln1 protein of the yeast Saccharomyces cerevisiae has sequence similarities to both the histidine kinase and the response regulator proteins of bacteria. A missense mutation in SLN1 is lethal in the absence but not in the presence of the N-end rule pathway, a ubiquitin-dependent proteolytic system. The finding of SLN1 demonstrates that a mode of signal transduction similar to the bacterial two-component design operates in eukaryotes as well.

Ptc1, a type 2C Ser/Thr phosphatase, inactivates the HOG pathway by dephosphorylating the mitogen-activated protein kinase Hog1.

The HOG (high-osmolarity glycerol) mitogen-activated protein kinase (MAPK) pathway regulates the osmotic stress response in the yeast Saccharomyces cerevisiae. Three type 2C Ser/Thr phosphatases (PTCs), Ptc1, Ptc2, and Ptc3, have been isolated as negative regulators of this pathway. Previously, multicopy expression of PTC1 and PTC3 was shown to suppress lethality of the sln1Delta strain due to hyperactivation of the HOG pathway. In this work, we show that PTC2 also suppresses sln1Delta lethality. Furthermore, the phosphatase activity of these PTCs was needed for suppression, as mutation of a conserved Asp residue, likely to coordinate a metal ion, inactivated PTCs. Further analysis of Ptc1 function in vivo showed that it inactivates the MAPK, Hog1, but not the MEK, Pbs2. In the wild type, Hog1 kinase activity increased transiently, approximately 12-fold in response to osmotic stress, while overexpression of PTC1 limited activation to approximately 3-fold. In contrast, overexpression of PTC1 did not inhibit phosphorylation of Hog1 Tyr in the phosphorylation lip, suggesting that Ptc1 does not act on Pbs2. Deletion of PTC1 also strongly affected Hog1, leading to high basal Hog1 activity and sustained Hog1 activity in response to osmotic stress, the latter being consistent with a role for Ptc1 in adaptation. In vitro, Ptc1 but not the metal binding site mutant, Ptc1D58N, inactivated Hog1 by dephosphorylating the phosphothreonine but not the phosphotyrosine residue in the phosphorylation lip. Consistent with its role as a negative regulator of Hog1, which accumulates in the nucleus upon activation, Ptc1 was found in both the nucleus and the cytoplasm. Thus, one function of Ptc1 is to inactivate Hog1.

Differential regulation of the cell wall integrity mitogen-activated protein kinase pathway in budding yeast by the protein tyrosine phosphatases Ptp2 and Ptp3.

Mitogen-activated protein kinases (MAPKs) are inactivated by dual-specificity and protein tyrosine phosphatases (PTPs) in yeasts. In Saccharomyces cerevisiae, two PTPs, Ptp2 and Ptp3, inactivate the MAPKs, Hog1 and Fus3, with different specificities. To further examine the functions and substrate specificities of Ptp2 and Ptp3, we tested whether they could inactivate a third MAPK, Mpk1, in the cell wall integrity pathway. In vivo and in vitro evidence indicates that both PTPs inactivate Mpk1, but Ptp2 is the more effective negative regulator. Multicopy expression of PTP2, but not PTP3, suppressed growth defects due to the MEK kinase mutation, BCK1-20, and the MEK mutation, MKK1-386, that hyperactivate this pathway. In addition, deletion of PTP2, but not PTP3, exacerbated growth defects due to MKK1-386. Other evidence supported a role for Ptp3 in this pathway. Expression of MKK1-386 was lethal in the ptp2Delta ptp3Delta strain but not in either single PTP deletion strain. In addition, the ptp2Delta ptp3Delta strain showed higher levels of heat stress-induced Mpk1-phosphotyrosine than the wild-type strain or strains lacking either PTP. The PTPs also showed differences in vitro. Ptp2 was more efficient than Ptp3 at binding and dephosphorylating Mpk1. Another factor that may contribute to the greater effectiveness of Ptp2 is its subcellular localization. Ptp2 is predominantly nuclear whereas Ptp3 is cytoplasmic, suggesting that active Mpk1 is present in the nucleus. Last, PTP2 but not PTP3 transcript increased in response to heat shock in a Mpk1-dependent manner, suggesting that Ptp2 acts in a negative feedback loop to inactivate Mpk1.

The gamma subunit of brain G-proteins is methyl esterified at a C-terminal cysteine.

The gamma polypeptide of brain G-proteins is carboxyl methylated when the purified beta gamma subunit complex is reconstituted with S-adenosyl-[3H-methyl]-L-methionine and a methyltransferase present in detergent-stripped brain membranes. By chromatographic analysis of the 3H-amino acid generated by exhaustive proteolysis and performic acid oxidation of the 3H-methylated beta gamma complex, we show that this modification occurs on the alpha-carboxyl group of a C-terminal cysteine residue. Our result suggests that brain G-protein may undergo multiple covalent modification steps, including proteolytic removal of the three terminal amino acids from the predicted common C-terminal Cys-Xaa-Xaa-Xaa sequence, and the methyl esterification of the resulting terminal cysteine residue. This modification is likely to be associated with lipidation at the sulfhydryl group of the same cysteine, which would explain the tight membrane binding property of the brain beta gamma complex.

Transfection with mutant p53 gene inhibits heat-induced apoptosis in a head and neck cell line of human squamous cell carcinoma.

PURPOSE: To confirm that human cancer cells show p53-dependent heat sensitivity through an apoptosis-related mechanism, we examined the heat sensitivity and Bax-mediated apoptosis after heating in a human squamous cell carcinoma cell line, SAS, with identical genetic backgrounds except for the p53 status. MATERIALS AND METHODS: We performed colony formation assay, Western blotting and analyses of apoptosis, using the SAS cells transfected with pC53-248 vector with mutant p53 gene (SAS/Trp248 cells) or the cells transfected with pCMV-Neo-Bam vector (SAS/neo cells) as a control. RESULTS: SAS/Trp248 cells showed heat resistance due to the dominant negative nature of mp53, compared with SAS/neo cells. The incidence of DNA ladders and apoptotic bodies increased markedly after heating in SAS/neo cells, but increased very little in SAS/Trp248 cells. CONCLUSION: These results suggest that heat resistance brought by mp53-transfection is p53-dependent and closely correlates with the induction of apoptosis in human squamous cell carcinomas.

Characteristic ERG-flicker anomaly in incomplete congenital stationary night blindness.

Ten patients with the incomplete type of congenital stationary night blindness (CSNB) were examined with a 30 Hz flicker electroretinogram (ERG). After 30 min of dark adaptation, 30 Hz flicker ERG was recorded continuously for 12-15 min under white background illumination. All patients showed an exaggerated increase of amplitude and a universal characteristic change of wave shape as the light adaptation progressed. Thirty normal subjects also showed increased amplitude during light adaptation, but the increase in amplitude was significantly less than in incomplete-type CSNB, and there was little change in wave shape. The same procedure was applied to patients with complete-type CSNB, retinitis pigmentosa, congenital retinoschisis, cone dystrophy, and Oguchi's disease; neither the exaggerated increase of amplitude nor the wave change was seen. Our results indicate that incomplete-type CSNB is a newly identified cone-rod dysfunction syndrome with a special functional property.

Oscillatory potentials in electroretinograms of the human macular region.

Using focal stimuli, we successfully recorded oscillatory potentials (OPs) in electroretinograms of the macular regions of 72 normal volunteers. The OPs consisted of three to four wavelets with a mean peak interval of approximately 6.5 msec, consistent with that recorded with conventional full-field stimuli over the entire retina. The changes of amplitude in response to the spot sizes and ring stimuli suggested that the distribution of OPs is different from that in a- and b-waves in human macular region.

Asymmetry of focal ERG in human macular region.

Electroretinograms (ERGs) were elicited by hemicircular (half-disc) stimuli to the upper, lower, temporal and nasal maculas of 26 normal subjects, and the amplitudes and implicit times of the ERGs from opposing macular regions were compared. The amplitudes of a-wave, b-wave and oscillatory potentials (OPs) were significantly larger in the upper macular region than in the lower macular region (P less than 0.05). The amplitudes of a- and b-waves did not differ significantly between temporal and nasal macular regions, but OPs showed enormous asymmetry, with significantly larger amplitudes in the temporal retina than in the nasal retina (P less than 0.001). The implicit times of a-waves, b-waves and OPs did not differ significantly between upper and lower retina, or between temporal and nasal retina. These findings aided analysis of the ERG of a patient with a retinal defect.

Focal macular electroretinogram in X-linked congenital retinoschisis.

PURPOSE: To study macular function of X-linked congenital retinoschisis (CRS) by focal macular electroretinogram (MERG). METHODS: MERGs were recorded with 5 degrees, 10 degrees, and 15 degrees spots in 20 patients with CRS. Seventeen patients showed foveal schisis with little or no change in foveal fluorescein angiography (Group 1), and three patients showed advanced macular changes with nonspecific macular degeneration (Group 2). RESULTS: In Group 1, a-wave amplitudes were within the normal range, but b-waves and oscillatory potentials (OPs) had mean amplitudes significantly below those for normal control subjects. The mean b- to a-wave ratios, significantly lower than in normal eyes, decreased significantly with decreasing spot size. The implicit times of a-waves, b-waves, and OPs were significantly delayed. In Group 2, MERGs were nearly nondectable. CONCLUSIONS: The macular pathology of CSR exists mainly in the middle and inner retinal layers, disturbing the fovea more than the perifovea, whereas degeneration of photoreceptors progresses in more advanced stage.

CDDP induces p53-dependent apoptosis in tongue cancer cells.

We have investigated the CDDP sensitivities of two tongue cancer cell lines with differing p53 genetic status, one with wild-type p53 (SAS) and the other with mutant-type p53 (HSC-4). SAS was about 2 times more sensitive at the D10 dose and demonstrated increased p53 and Bax protein levels at 10 h after CDDP treatment on Western blot analysis. On the other hand, overexpression of p53 in HSC-4 was observed without CDDP treatment and no elevation of Bax could be detected. Apoptosis was observed after CDDP treatment in SAS but not in HSC-4 by Hoechst 33342-staining and electrophoresis methods. These findings indicate that p53 plays an important role in apoptosis as a positive regulator of Bax expression. It is suggested that p53 status may have predictive potential with regard to response to CDDP therapy.

Latanoprost accelerates disruption of the blood-aqueous barrier and the incidence of angiographic cystoid macular edema in early postoperative pseudophakias.

OBJECTIVE: To study the effect of latanoprost, a prostaglandin analog, on the blood-aqueous barrier and angiographic cystoid macular edema (CME) formation in early postoperative pseudophakias. PATIENTS AND METHODS: Included in the study were eyes with ocular hypertension, normal-tension glaucoma, or primary open-angle glaucoma undergoing surgery for cataract. The study consisted of a randomized double-masked trial for latanoprost and an open-label controlled trial for determining the effects of diclofenac sodium or fluorometholone eyedrop use on latanoprost or its placebo. We compared 4 groups of eyes with concurrent application of latanoprost and diclofenac (group A), latanoprost and fluorometholone (group B), latanoprost placebo and diclofenac (group C), and latanoprost placebo and fluorometholone (group D). A laser flare cell meter was used to determine the severity of blood-aqueous barrier disruption, and fluorescein angiography was performed to determine angiographic CME formation. Mean diurnal intraocular pressure differences were compared on the preoperative baseline day and in the fifth postoperative week. Latanoprost (0.005%) or its placebo was given once a day starting 2 days before surgery until the fifth postoperative week. Diclofenac or fluorometholone eyedrops were given 4 times a day before surgery on the day of surgery and 3 times a day until the fifth postoperative week. RESULTS: In group B compared with group D, the amount of flare 3 days and 1 and 2 weeks after surgery and the incidence of angiographic CME in the fifth postoperative week were significantly higher. These 2 factors were significantly higher in group B than in group A (P < .05) and in group D than in group C (P < .01). There was no significant difference in these factors between groups A and C. The intraocular pressure decline was significant in groups A and B compared with groups C and D (P < .05), but there was no significant difference between groups A and B and between groups C and D. CONCLUSIONS: Latanoprost therapy enhances disruption of the blood-aqueous barrier and increases the incidence of angiographic CME formation in early postoperative pseudophakias. Because administration of nonsteroidal eyedrops such as diclofenac seems to prevent the adverse effects of latanoprost therapy while maintaining its effect to lower intraocular pressure, we suggest their concurrent application.

Application of a newly developed, highly sensitive camera and a 3-dimensional high-definition television system in experimental ophthalmic surgeries.

OBJECTIVE: To apply a new television system, which displays highly sensitive, high-quality 3-dimensional (3-D) images, in performing experimental ophthalmic surgeries. METHODS: By combining a high-gain avalanche rushing-amorphous photoconductor (HARP) camera, recently developed in Japan, which has 600 times greater sensitivity than conventional television cameras, and a single-camera, 3-D high-definition television system, which displays high-quality 3-D images, we performed cataract/intraocular lens surgeries and pars plana vitrectomies under various illumination intensities in pig cadaver eyes. RESULTS: Cataract/intraocular lens surgeries were performed using 7.3% the intensity of ordinary surgical microscopic illumination; vitrectomies were performed using 30.2% the intensity of an ordinary endoillumination probe with the HARP camera and by observing the stereoscopic display of the single-camera 3-D high-definition television system. Images identical to those observed by the surgeon were displayed on the stereoscopic display monitor. CONCLUSION: The system not only allowed surgeries to be performed under lower intensities of operating light but also provided real-time, highly sensitive 3-D images identical to those observed by the surgeon; thus, the device may be effectively used for education, team surgery, and telesurgery. CLINICAL RELEVANCE: The new television system for ocular surgeries to be performed under lower intensities of operating light as well as providing real-time, highly sensitive 3-D images identical to those observed by the surgeon may be effectively used for education and telesurgery.

Enhanced disruption of the blood-aqueous barrier and the incidence of angiographic cystoid macular edema by topical timolol and its preservative in early postoperative pseudophakia.

OBJECTIVE: To investigate the effects of timolol maleate with preservative and its preserved (PV) and nonpreserved vehicles (NPV) (benzalkonium chloride) on the blood-aqueous barrier and angiographic cystoid macular edema (CME) in early postoperative pseudophakia. PATIENTS AND METHODS: Patients with ocular hypertension, normal tension glaucoma, and primary open-angle glaucoma who underwent surgery for cataracts. The study included a double-masked trial for timolol, PV, and NPV and a single-masked trial on the effect of diclofenac sodium and fluorometholone acetate on all three. The patients were divided into 6 groups, each of which were simultaneously administered the following different combinations of compounds: timolol and diclofenac (group A), timolol and fluorometholone (group B), PV and diclofenac (group C), PV and fluorometholone (group D), NPV and diclofenac (group E), and NPV and fluorometholone (group F). The 6 groups were then compared using a laser flare cell meter to determine the degree of disruption of the blood-aqueous barrier and fluorescein angiography to investigate angiographic CME. The differences in mean daily fluctuations in intraocular pressure were compared on the preoperative baseline day and for 5 weeks postoperatively. Twice daily administration of 0.5% timolol maleate or the vehicles was started 2 days before surgery, and continued until 5 weeks after surgery. Diclofenac or fluorometholone drops were instilled in the eyes 4 times preoperatively, on the day of surgery, and 3 times daily for 5 weeks postoperatively. RESULTS: The flare amount was higher on the third and seventh days in group B than in group D, but was the same after the seventh day. The incidence of angiographic CME was the same between both groups. These 2 factors were significantly lower in group F. These 2 factors were also significantly lower in the 3 groups that received diclofenac instead of fluorometholone, with no difference among these groups. The intraocular pressure decline was significant in groups that received timolol compared with groups that received PV or NPV. CONCLUSIONS: Timolol and its preservative, benzalkonium chloride, cause disruption of the blood-aqueous barrier in early postoperative pseudophakia and increased incidence of angiographic CME. The concurrent administration of nonsteroidal anti-inflammatory drug such as diclofenac prevents these adverse effects without interfering with the drop in intraocular pressure caused by timolol. The addition of benzalkonium chloride to timolol contributes considerably to these adverse effects. CLINICAL RELEVANCE: The present results suggest the cause of similar complications produced by other antiglaucoma eyedrops containing similar preservatives.

Effects of fibronectin cleaved by neuropsin on cell adhesion and migration.

Neuropsin is a serine protease cloned from the mouse hippocampus. Since neuropsin is a secreted protein which effectively cleaves fibronectin, it may affect cell adhesion or cell migration by modulating the content and/or chemical characteriscs of fibronectin in extracellular matrix (ECM). In adhesion assays, alpha5B2 cells expressing integrin alpha5beta1 bound less effectively to fibronectin teated with neuropsin than intact fibronectin. In Boyden chamber chemotaxis assays, the fibronectin-induced migration of alpha5B2 cells was not affected by neuropsin treatment. These findings suggest that neuropsin regulates the local microenvironment by modulating the interaction between cells and fibronectin in ECM.

Morphological and cytogenetic changes in therapy-related leukemia developed in a t(8;21)-acute myeloid leukemia (M2) patient: sequential cytogenetic and molecular analyses.

A patient with acute myeloid leukemia (AML)-M2 with t(8;21)(q22;q22) achieved complete remission with remission-induction chemotherapy followed by consolidation and intensification chemotherapies. T(8;21)(q22;q22) disappeared, but chimeric AML1/MTG8 was continuously detected in bone marrow cells. Following the development of therapy-related leukemia after 1 year, evolution of therapy-related AML-M4 with t(11;17)(q23;q25) and the rearrangement of the MLL gene were observed, while AML/MTG8 disappeared. After reinduction and following intermittent chemotherapies, a subsequent alternative transformation to AML-M2 occurred after detection of t(3;21)(q21;q22), with a break in the AML1 gene shown by interphase fluorescence in situ hybridization analysis. This leukemia transformed to AML-M4 after t(9;22)(q34;q11), with a minor BCR/ABL rearrangement, and then finally to AML-M2. This therapy-related leukemia was resistant to chemotherapy. These findings indicate that alterations in cytogenetic and molecular events caused by chemotherapeutic agents contribute to the sequential evolution of new leukemic clones with different morphology.

Dislocation of the lens nucleus into the vitreous cavity after standard hydrodissection.

PURPOSE: Having encountered dislocation of the lens nucleus into the vitreous cavity immediately after continuous tear capsulorhexis and hydrodissection of the nucleus, we examined common features of eyes with this complication. METHODS: We reviewed consecutive cases of cataract extraction. RESULTS: The complication occurred in four of 10,126 eyes. All four eyes were in elderly patients and except for the patient whose contralateral eye had pseudoexfoliation syndrome, all eyes had an increased axial length. CONCLUSION: In elderly patients with eyes that have a long axial length or pseudoexfoliation, we recommend performing hydrodissection with extreme care and only when necessary.

Local macular electroretinographic responses in idiopathic central serous chorioretinopathy.

Using focal stimuli to human macular regions, we recorded electroretinograms in 24 patients with central serous chorioretinopathy of recent onset (mean visual acuity, 20/20). The stimulus spot was 10 degrees in diameter. Intact fellow eyes served as controls. The local macular electroretinograms of the affected eyes were significantly reduced and the implicit time in each component was significantly prolonged. The mean (+/- S.D.) amplitudes, expressed as percentages of mean amplitudes recorded in fellow eyes, were 64.6% +/- 22.7% (a-wave), 49.6% +/- 21.0% (b-wave), and 15.0% +/- 21.6% (oscillatory potentials). Two to five months after the macular detachment resolved, recordings in 18 patients showed remarkable recovery of a- and b-waves and shortened implicit times. However, the oscillatory potentials showed significantly small recovery in amplitude. Since oscillatory potentials and b-waves were significantly more deteriorated than a-waves in the presence of macular detachment, and oscillatory potentials showed selective delay of recovery in the convalescent stage, central serous chorioretinopathy may involve functional disturbances in the inner retinal layer as well as the photoreceptors.