The anti-tumor effect of trifluridine via induction of aberrant mitosis is unaffected by mutations modulating p53 activity.

The fluorinated thymidine analog trifluridine (FTD) is a chemotherapeutic drug commonly used to treat cancer; however, the mechanism by which FTD induces cytotoxicity is not fully understood. In addition, the effect of gain-of-function (GOF) missense mutations of the TP53 gene (encoding p53), which promote cancer progression and chemotherapeutic drug resistance, on the chemotherapeutic efficacy of FTD is unclear. Here, we revealed the mechanisms by which FTD-induced aberrant mitosis and contributed to cytotoxicity in both p53-null and p53-GOF missense mutant cells. In p53-null mutant cells, FTD-induced DNA double-stranded breaks, single-stranded DNA accumulation, and the associated DNA damage responses during the G2 phase. Nevertheless, FTD-induced DNA damage and the related responses were not sufficient to trigger strict G2/M checkpoint arrest. Thus, these features were carried over into mitosis, resulting in chromosome breaks and bridges, and subsequent cytokinesis failure. Improper mitotic exit eventually led to cell apoptosis, caused by the accumulation of extensive DNA damage and the presence of micronuclei encapsulated in the disrupted nuclear envelope. Upon FTD treatment, the behavior of the p53-GOF-missense mutant, isogenic cell lines, generated by CRISPR/Cas9 genome editing, was similar to that of p53-null mutant cells. Thus, our data suggest that FTD treatment overrode the effect on gene expression induced by p53-GOF mutants and exerted its anti-tumor activity in a manner that was independent of the p53 function.

Randomized Multicenter Clinical Trial Comparing 0.1% Brimonidine/0.5% Timolol Versus 1% Dorzolamide/0.5% Timolol as Adjuncts to Prostaglandin Analogues: Aibeta Crossover Study.

INTRODUCTION: This multicenter, randomized, comparative, and investigator-masked crossover clinical trial sought to compare the efficacy and tolerability of fixed combinations of 0.1% brimonidine/0.5% timolol (BTFC) versus 1% dorzolamide/0.5% timolol (DTFC) as adjunctive therapies to prostaglandin analogues. METHODS: A total of 110 patients with open-angle glaucoma or ocular hypertension previously treated with prostaglandin analogue monotherapy were randomized to receive either BTFC or DTFC as adjunctive therapy for 8 weeks. These patients were then crossed over to the alternative treatment arm for another 8 weeks. The reduction in intraocular pressure (IOP) (primary outcome), occurrence of adverse events, ocular discomfort after instillation, and patient preference (secondary outcomes) were recorded through patient interviews. RESULTS: BTFC instillation for 8 weeks reduced IOP by 3.55 mmHg, demonstrating non-inferiority to DTFC instillation (3.60 mmHg; P < 0.0001, mixed-effects model). Although adverse events were rare with both combinations, patients reported greater discomfort with DTFC than with BTFC (P < 0.0001). More patients preferred BTFC (P < 0.0001) over DTFC, as BTFC caused minimal or no eye irritation. CONCLUSION: As BTFC offered better tolerability than DTFC with comparable reduction in IOP, we recommend it as an alternative for patients who experience ocular discomfort with DTFC-prostaglandin analogue combination therapy. TRIAL REGISTRATION NUMBER: jRCTs051190125.

Patients with glaucoma who require further reduction in intraocular pressure while undergoing monotherapy with prostaglandin analogue ophthalmic solution have been prescribed two enhanced treatment options: 0.1% brimonidine/0.5% timolol fixed combination ophthalmic solution (BTFC) and 1% dorzolamide/0.5% timolol fixed combination ophthalmic solution (DTFC). The Aibeta Crossover Study Group in Japan compared the efficacy and tolerability of fixed combinations of BTFC versus DTFC when an additional fixed combination ophthalmic solution was prescribed in patients with open-angle glaucoma or ocular hypertension who had been treated with prostaglandin analogue monotherapy. We recruited 110 patients previously treated with prostaglandin analogue monotherapy at 20 clinical centers in Japan, then randomly assigned them to two alternative treatment groups: the BTFC to DTFC group or the DTFC to BTFC group, as an adjunctive therapy to prostaglandin analogues for total of 16 weeks. We compared the reduction in intraocular pressure, occurrence of side effects, eye discomfort after instillation, and patient preference between BTFC versus DTFC instillations. The intraocular pressure reduction of BTFC instillation was comparable to that of DTFC instillation, showing non-inferiority to DTFC (3.55 mmHg vs. 3.60 mmHg; P < 0.0001, mixed-effects model). Both eye drops caused few side effects; however, patients felt greater eye discomfort with DTFC than with BTFC (P < 0.0001). Because of less eye irritation, more patients preferred BTFC (P < 0.0001) over DTFC. We can recommend using BTFC for patients who feel eye discomfort with DTFC­prostaglandin analogue combination therapy.

Discovery of Futibatinib: The First Covalent FGFR Kinase Inhibitor in Clinical Use.

Deregulating fibroblast growth factor receptor (FGFR) signaling is a promising strategy for cancer therapy. Herein, we report the discovery of compound 5 (TAS-120, futibatinib), a potent and selective covalent inhibitor of FGFR1-4, starting from a unique dual inhibitor of mutant epidermal growth factor receptor and FGFR (compound 1). Compound 5 inhibited all four families of FGFRs in the single-digit nanomolar range and showed high selectivity for over 387 kinases. Binding site analysis revealed that compound 5 covalently bound to the cysteine 491 highly flexible glycine-rich loop region of the FGFR2 adenosine triphosphate pocket. Futibatinib is currently in Phase I-III trials for patients with oncogenically driven FGFR genomic aberrations. In September 2022, the U.S. Food & Drug Administration granted accelerated approval for futibatinib in the treatment of previously treated, unresectable, locally advanced, or metastatic intrahepatic cholangiocarcinoma harboring an FGFR2 gene fusion or other rearrangement.

Lineage of drug discovery research on fluorinated pyrimidines: chronicle of the achievements accomplished by Professor Setsuro Fujii.

Prof. Setsuro Fujii achieved significant results in the field of drug discovery research in Japan. He developed nine well-known drugs: FT, UFT, S-1 and FTD/TPI are anticancer drugs, while cetraxate hydrochloride, camostat mesilate, nafamostat mesilate, gabexate mesilate and pravastatin sodium are therapeutic drugs for various other diseases. He delivered hope to patients with various diseases across the world to improve their condition. Even now, drug discovery research based on Dr. Fujii's ideas is continuing.

The Efficacy, Safety, and Satisfaction Associated with Switching from Brinzolamide or Brimonidine to Brinzolamide/Brimonidine in Open-Angle Glaucoma Patients.

We evaluated switching from brinzolamide 1% or brimonidine 0.1% to a fixed-combination of brinzolamide 1% and brimonidine 0.1%, and then determined the efficacy, safety, and satisfaction associated with these changes in glaucoma patients. This prospective, nonrandomized study evaluated a total of 31 enrolled glaucoma patients who underwent treatment with at least brinzolamide 1% or brimonidine 0.1%. Patients were administered a brinzolamide/brimonidine fixed-combination ophthalmic suspension (BBFC) after being switched from their original brinzolamide 1% or brimonidine 0.1% therapy. All other intraocular pressure (IOP)-lowering medications currently being used were continued. IOP, superficial punctate keratopathy (SPK), and conjunctival hyperemia data obtained at baseline and then at 4 and 12 weeks were evaluated. To assess the changes in treatment satisfaction, this study utilized the Treatment Satisfaction Questionnaire for Medication-9 (TSQM-9). There was a significant decrease in the mean baseline IOP from 15.7 ± 4.9 mmHg to 13.6 ± 4.4 (p = 0.001) and 13.5 ± 3.9 mmHg (p = 0.002) at 4 and 12 weeks, respectively. Evaluation of the incidence of conjunctival hyperemia or SPK score showed there were no significant changes noted at any time point. The TSQM-9 score demonstrated there was a significant increase for effectiveness after switching from brinzolamide 1% or brimonidine 0.1% to BBFC. After switching from brinzolamide 1% or brimonidine 0.1% to BBFC, there was a significant decrease in the IOP. Patients were aware of the effectiveness of switching from brinzolamide 1% or brimonidine 0.1% to BBFC.

The Efficacy, Safety and Satisfaction Associated with Switching from Brinzolamide 1% and Brimonidine 0.1% to a Fixed Combination of Brinzolamide 1% and Brimonidine 0.1% in Glaucoma Patients.

We evaluated glaucoma patients for the efficacy, safety and satisfaction associated with switching from brinzolamide 1% and brimonidine 0.1% to a fixed combination of brinzolamide 1% and brimonidine 0.1%. A total of 22 glaucoma patients were enrolled and completed this prospective, nonrandomized study that evaluated patients who underwent treatment with at least brinzolamide 1% and brimonidine 0.1%. Patients on brinzolamide 1% and brimonidine 0.1% were switched to a brinzolamide/brimonidine fixed-combination ophthalmic suspension (BBFC). Evaluations of intraocular pressure (IOP), superficial punctate keratopathy (SPK) and conjunctival hyperemia were conducted at baseline and at 4 and 12 weeks. The Treatment Satisfaction Questionnaire for Medication-9 (TSQM-9) was utilized to assess the change in treatment satisfaction. At baseline and at 4 and 12 weeks, the IOP was 15.0 ± 4.1, 14.8 ± 4.1 and 14.8 ± 4.1 mmHg, respectively. There were no significant differences observed at any of the time points. However, the SPK score significantly decreased at 12 weeks, even though no significant differences were observed for the conjunctival hyperemia incidence at any of the time points. After switching from brinzolamide 1% and brimonidine 0.1% to BBFC, there was a significant increase in the TSQM-9 score for convenience and global satisfaction. Both an improvement in the degree of SPK and an increase in treatment satisfaction occurred after switching from brinzolamide 1% and brimonidine 0.1% to BBFC, even though there were sustained IOP values throughout the 12-week evaluation period.

Futibatinib Is a Novel Irreversible FGFR 1-4 Inhibitor That Shows Selective Antitumor Activity against FGFR-Deregulated Tumors.

FGFR signaling is deregulated in many human cancers, and FGFR is considered a valid target in FGFR-deregulated tumors. Here, we examine the preclinical profile of futibatinib (TAS-120; 1-[(3S)-[4-amino-3-[(3,5-dimethoxyphenyl)ethynyl]-1H-pyrazolo[3, 4-d] pyrimidin-1-yl]-1-pyrrolidinyl]-2-propen-1-one), a structurally novel, irreversible FGFR1-4 inhibitor. Among a panel of 296 human kinases, futibatinib selectively inhibited FGFR1-4 with IC50 values of 1.4 to 3.7 nmol/L. Futibatinib covalently bound the FGFR kinase domain, inhibiting FGFR phosphorylation and, in turn, downstream signaling in FGFR-deregulated tumor cell lines. Futibatinib exhibited potent, selective growth inhibition of several tumor cell lines (gastric, lung, multiple myeloma, bladder, endometrial, and breast) harboring various FGFR genomic aberrations. Oral administration of futibatinib led to significant dose-dependent tumor reduction in various FGFR-driven human tumor xenograft models, and tumor reduction was associated with sustained FGFR inhibition, which was proportional to the administered dose. The frequency of appearance of drug-resistant clones was lower with futibatinib than a reversible ATP-competitive FGFR inhibitor, and futibatinib inhibited several drug-resistant FGFR2 mutants, including the FGFR2 V565I/L gatekeeper mutants, with greater potency than any reversible FGFR inhibitors tested (IC50, 1.3-50.6 nmol/L). These results indicate that futibatinib is a novel orally available, potent, selective, and irreversible inhibitor of FGFR1-4 with a broad spectrum of antitumor activity in cell lines and xenograft models. These findings provide a strong rationale for testing futibatinib in patients with tumors oncogenically driven by FGFR genomic aberrations, with phase I to III trials ongoing. SIGNIFICANCE: Preclinical characterization of futibatinib, an irreversible FGFR1-4 inhibitor, demonstrates selective and potent antitumor activity against FGFR-deregulated cancer cell lines and xenograft models, supporting clinical evaluation in patients with FGFR-driven tumors. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/22/4986/F1.large.jpg.

TAS-120 Overcomes Resistance to ATP-Competitive FGFR Inhibitors in Patients with FGFR2 Fusion-Positive Intrahepatic Cholangiocarcinoma.

ATP-competitive fibroblast growth factor receptor (FGFR) kinase inhibitors, including BGJ398 and Debio 1347, show antitumor activity in patients with intrahepatic cholangiocarcinoma (ICC) harboring activating FGFR2 gene fusions. Unfortunately, acquired resistance develops and is often associated with the emergence of secondary FGFR2 kinase domain mutations. Here, we report that the irreversible pan-FGFR inhibitor TAS-120 demonstrated efficacy in 4 patients with FGFR2 fusion-positive ICC who developed resistance to BGJ398 or Debio 1347. Examination of serial biopsies, circulating tumor DNA (ctDNA), and patient-derived ICC cells revealed that TAS-120 was active against multiple FGFR2 mutations conferring resistance to BGJ398 or Debio 1347. Functional assessment and modeling the clonal outgrowth of individual resistance mutations from polyclonal cell pools mirrored the resistance profiles observed clinically for each inhibitor. Our findings suggest that strategic sequencing of FGFR inhibitors, guided by serial biopsy and ctDNA analysis, may prolong the duration of benefit from FGFR inhibition in patients with FGFR2 fusion-positive ICC. SIGNIFICANCE: ATP-competitive FGFR inhibitors (BGJ398, Debio 1347) show efficacy in FGFR2-altered ICC; however, acquired FGFR2 kinase domain mutations cause drug resistance and tumor progression. We demonstrate that the irreversible FGFR inhibitor TAS-120 provides clinical benefit in patients with resistance to BGJ398 or Debio 1347 and overcomes several FGFR2 mutations in ICC models.This article is highlighted in the In This Issue feature, p. 983.

SLC1A1 Gene Variants and Normal Tension Glaucoma: An Association Study.

BACKGROUND: It has been hypothesized that dysfunction of the solute carrier family 1, member1 gene (SLC1A1), which encodes the glutamate aspartate transporter, may play a role in normal tension glaucoma. In this study we investigate whether SLC1A1 is associated with normal tension glaucoma in Japanese patients. METHODS: A total of 292 Japanese patients with normal tension glaucoma and 500 healthy control subjects were recruited. We genotyped 12 single-nucleotide polymorphisms in SLC1A1. We also performed an imputation analysis to evaluate the potential association of un-genotyped SLC1A1 single-nucleotide polymorphisms, and 165 single-nucleotide polymorphisms were imputed. RESULTS: We observed an increased frequency of the G allele of rs10739062 in patients compared to controls (p = 0.043, OR = 1.25). The rs10739062 polymorphism exhibited a dominant effect: individuals with genotype GG and GC showed a 1.91-fold increase in risk compared to genotype CC (p = 0.0082). However, the statistical significance disappeared after Bonferroni correction for multiple testing (pc > 0.05). We did not find any significant association between any of the remaining 176 single-nucleotide polymorphisms and disease risk. CONCLUSIONS: Our study showed a lack of association between SLC1A1 variants and normal tension glaucoma in Japanese patients, suggesting that the SLC1A1 gene does not play a critical role in the development of the disorder in this patient population. However, further genetic studies with larger sample sizes are needed to clarify whether SLC1A1 may make some contribution that affects the risk of developing normal tension glaucoma.

Safety and Efficacy of Benzalkonium Chloride-optimized Tafluprost in Japanese Glaucoma Patients With Existing Superficial Punctate Keratitis.

PURPOSE: To evaluate the safety and efficacy of benzalkonium chloride (BAK)-optimized tafluprost (with a BAK concentration reduced from 0.01% to 0.001%) in glaucoma patients with existing superficial punctate keratitis (SPK). PATIENTS AND METHODS: A prospective, multicenter, open-label study was designed to compare BAK-optimized tafluprost administered over 12 weeks relative to other preserved prostaglandin analogs previously administered in Japanese glaucoma patients. Thirty patients with SPK graded at <6 points by area density (AD) scoring in 1 eye were recruited. The primary outcome measure was change in AD score at 12 weeks after the switch in treatment compared with that at baseline. Secondary outcome measures included changes in tear film breakup time (TBUT), hyperemia score, and intraocular pressure (IOP). Four patients were excluded from analysis because of treatment discontinuation. RESULTS: Mean AD score±SD decreased significantly from 3.4±0.9 to 1.8±1.8 after the switch (P<0.0001). Mean TBUT increased significantly from 6.3±3.3 to 8.0±4.2 seconds (P<0.01). Mean hyperemia score remained unchanged, whereas mean IOP decreased significantly from 15.6±2.6 to 14.4±2.0 mm Hg (P<0.01). For patients previously treated with BAK-preserved latanoprost (n=17) or bimatoprost (n=2), mean AD score decreased significantly from 3.4±0.9 to 1.8±1.8 (P<0.01) and mean TBUT increased significantly from 6.4±3.6 to 8.2±4.3 seconds (P<0.01); no such changes were apparent for patients previously treated with sofZia-preserved travoprost (n=7). CONCLUSIONS: BAK-optimized tafluprost is a treatment option to improve the condition of the ocular surface and to maintain IOP control in glaucoma patients with existing SPK who have been previously treated with other BAK-preserved prostaglandin analogs.

Intraobserver and interobserver agreement of computer software-assisted optic nerve head photoplanimetry.

PURPOSE: To report the reproducibility profile of optic nerve head parameters obtained by computer software-assisted fundus photoplanimetry. METHODS: Fundus photographs obtained during a population-based health survey (Sakurae Study) were planimetrically analyzed using newly developed computer software, CDSketch. The parameters assessed included vertical and horizontal cup-to-disc (C/D) ratios, superior and inferior rim-to-disc (R/D) ratios, disc and cup vertical-to-horizontal (V/H) ratios, and disc-macular distance-to-disc diameter (DM/DD) ratio. For intraobserver and interobserver agreement assessments, we calculated the coefficients of variation (CVs) and intraclass correlation coefficients (ICCs) of the mean of three measurements obtained by one observer and a one-time measurement by three observers, respectively. RESULTS: The intraobserver CVs were between 2.4 % (DM/DD ratio) and 11.0 % (inferior R/D ratio), and the ICCs were between 0.868 (cup V/H ratio) and 0.976 (DM/DD ratio); all intraobserver ICCs had almost perfect agreement (>0.81). The interobserver CVs were between 2.6 % (disc V/H ratio) and 18.0 % (inferior R/D ratio), and the ICCs were between 0.762 (cup V/H ratio) and 0.930 (DM/DD ratio); the interobserver ICCs were categorized as substantial (0.61-0.80) for the inferior R/D and cup V/H ratios and as almost perfect for the other five parameters. CONCLUSIONS: The consistent profiles of the planimetric parameters suggest the suitability of software-assisted photoplanimetry for assessing optic disc characteristics in glaucoma clinical study and practice.

[Fundus photoplanimetry of the optic nerve head in the Sakurae Study].

PURPOSE: To explore the fundus photoplanimetric distribution of the optic nerve head in a population-based health survey conducted in Sakurae area, in Shimane, Japan(the Sakurae Study). METHODS: After the exclusion of poor quality images from the 1660 right eye-fundus photos obtained from the Sakurae Study in 1991, 1583 photos were digitized, and then were planimetrically analyzed using a newly developed computer software, CDSketch. The parameters calculated included vertical and horizontal cup-to-disc (C/D) ratios, superior and inferior rim-to-disc (R/D) ratios, disc and cup vertical-to-horizontal (V/H) ratios, and disc-macular distance-to-disc diameter (DM/DD) ratio. RESULTS: For the vertical and horizontal C/D, superior and inferior R/D, disc and cup V/H, and DM/DD ratios, mean values were calculated to be 0.58, 0.59, 0.20, 0.18, 1.11, 1.09, 2.60, respectively, and median values were calculated to be 0.58, 0.59, 0.19, 0.18, 1.11, 1.09, 2.57, respectively; no parameter showed any remarkably skewed distribution. The vertical C/D ratio was positively correlated with the cup V/H ratio, but was not correlated with the disc V/ H ratio. The vertical and horizontal C/D, and the disc and cup V/H ratios were negatively correlated with the DM/DD ratio. CONCLUSIONS: The distributions of the various optic nerve head parameters and their correlations in the Sakurae Study are reported. Both mean and median values of the vertical C/D ratio were approximately 0.6 in this study population. These values were larger than the previously reported C/D ratios obtained by direct ophthalmoscopic observations and/or by subjective methods.

Decrease in intraocular pressure following orthokeratology measured with a noncontact tonometer.

PURPOSE: Orthokeratology for correction of myopia reduces corneal power by flattening corneal curvature and thinning central corneal thickness (CCT). Measurement of intraocular pressure (IOP) with a noncontact tonometer is known to be affected by CCT and corneal curvature. We investigated the influence of orthokeratology on such measurements of IOP. METHODS: This was a prospective, interventional case series derived from a clinical trial of orthokeratology lenses in two hospitals. Both eyes of 45 subjects were fitted with reverse-geometry lenses, worn for more than 4 h overnight for 52 weeks. Uncorrected visual acuity, refraction, IOP (with a noncontact tonometer), CCT, and corneal curvature were measured. RESULTS: Uncorrected visual acuity, spherical equivalent value, IOP, CCT, and the radius of corneal curvature were 0.93 ± 0.27, -2.87 ± 1.05 D, 13.5 ± 2.5 mmHg, 536.2 ± 39.6 µm, and 7.88 ± 0.25 mm, respectively, before orthokeratology, and 0.17 ± 0.34, -1.05 ± 1.18 D, 12.4 ± 2.7 mmHg, 528.6 ± 40.8 µm, and 8.10 ± 0.31 mm at 52 weeks after treatment. The changes in all parameters were significant, and the change in IOP was significantly correlated with that in CCT at 24 weeks and thereafter. CONCLUSIONS: Orthokeratology for myopia leads to a decrease in IOP measured with a noncontact tonometer, likely as a result of the associated decrease in CCT.

Investigation of the association between SLC1A3 gene polymorphisms and normal tension glaucoma.

PURPOSE: To investigate whether the solute carrier family 1, member 3 (SLC1A3) gene, which encodes the glutamate aspartate transporter, is associated with normal tension glaucoma (NTG) in Japanese patients. METHODS: Two hundred and ninety-five Japanese patients with NTG and 518 Japanese healthy controls were recruited. Patients exhibiting comparatively early NTG onset were selected because early onset suggests that genetic factors may show stronger involvement. We genotyped 5 single-nucleotide polymorphisms (SNPs) in SLC1A3 and assessed the allelic and genotypic diversity among cases and controls. RESULTS: There were no statistically significant differences in the frequency of SLC1A3 alleles and genotypes between cases and controls. CONCLUSIONS: Our study showed no association between SLC1A3 and NTG, suggesting that the SLC1A3 gene may not be an associated factor in NTG pathogenesis.

Genotyping HLA-DRB1 and HLA-DQB1 alleles in Japanese patients with normal tension glaucoma.

PURPOSE: Normal tension glaucoma (NTG) is a subtype of glaucoma in which intraocular pressure is within the statistically normal range. NTG may be associated with an immune disorder. The aim of this study was to determine whether specific alleles in the human leukocyte antigen (HLA)-DRB1 and HLA-DQB1 genes correlated with NTG in Japanese patients. METHODS: We genotyped the HLA-DRB1 and HLA-DQB1 alleles in 113 Japanese patients with NTG and in 184 healthy Japanese control subjects using the polymerase chain reaction-sequence-specific oligonucleotide probes (PCR-SSOP) Luminex method. We assessed the allelic diversity in patients and controls. RESULTS: There were no statistically significant differences in the allele frequency of HLADRB1 and HLA-DQB1 between NTG patients and control subjects, and no HLA-DRB1-HLA-DQB1 haplotypes demonstrated any significant association with NTG. CONCLUSIONS: Our findings suggest that HLA-DRB1 and HLA-DQB1 polymorphisms have no significant effect on the development of NTG in Japanese patients.

Analysis of microsatellite polymorphisms within the GLC1F locus in Japanese patients with normal tension glaucoma.

PURPOSE: To investigate whether the GLC1F locus is associated with normal tension glaucoma (NTG) in Japanese patients. METHODS: We recruited 242 unrelated Japanese subjects, including, 141 NTG patients and 101 healthy controls. The patients exhibiting a comparatively early onset were selected as they suggest that genetic factors may show stronger involvement. Genotyping and assessment of allelic diversity was performed on 11 highly polymorphic microsatellite markers in and around the GLC1F locus. RESULTS: Individuals carrying the 163 allele of D7S1277i had a statistically significant increased risk of NTG (p=0.0013, pc=0.016, OR=2.47, 95%CI=1.42-4.30). None of the other markers identified significant loci (pc>0.05) after Bonferroni's correction. CONCLUSIONS: These findings suggested that the genes in the GLC1F locus may be associated with the pathogenesis of NTG.

Small-molecule inhibition of Wee1 kinase by MK-1775 selectively sensitizes p53-deficient tumor cells to DNA-damaging agents.

Wee1 is a tyrosine kinase that phosphorylates and inactivates CDC2 and is involved in G(2) checkpoint signaling. Because p53 is a key regulator in the G(1) checkpoint, p53-deficient tumors rely only on the G(2) checkpoint after DNA damage. Hence, such tumors are selectively sensitized to DNA-damaging agents by Wee1 inhibition. Here, we report the discovery of a potent and selective small-molecule inhibitor of Wee1 kinase, MK-1775. This compound inhibits phosphorylation of CDC2 at Tyr15 (CDC2Y15), a direct substrate of Wee1 kinase in cells. MK-1775 abrogates G(2) DNA damage checkpoint, leading to apoptosis in combination with DNA-damaging chemotherapeutic agents such as gemcitabine, carboplatin, and cisplatin selectively in p53-deficient cells. In vivo, MK-1775 potentiates tumor growth inhibition by these agents, and cotreatment does not significantly increase toxicity. The enhancement of antitumor effect by MK-1775 was well correlated with inhibition of CDC2Y15 phosphorylation in tumor tissue and skin hair follicles. Our data indicate that Wee1 inhibition provides a new approach for treatment of multiple human malignancies.

Association of microsatellite polymorphisms of the GPDS1 locus with normal tension glaucoma in the Japanese population.

BACKGROUND: To investigate whether the GPDS1 locus, a potential causative locus of pigment-dispersion syndrome, is associated with normal-tension glaucoma (NTG) in Japanese patients. MATERIALS AND METHODS: We used polymerase chain reaction amplification with sequence-specific primers to analyze 20 polymorphic microsatellite markers in and around the GPDS1 locus with an automated DNA analyzer and automated fragment detection by fluorescent-based technology. The DNA samples used for these analyses were obtained from ethnicity- and gender-matched patients, including 141 Japanese patients with NTG and 101 healthy controls. Patients exhibiting a comparatively early onset were selected as this suggests that genetic factors may show stronger involvement. RESULTS: One allele of D7S2462 exhibited a frequency that was significantly decreased in NTG cases compared to controls (P = 0.0013, Pc = 0.019, OR = 0.48, 95% CI = 0.30-0.75). Alleles at another six microsatellite loci were positively or negatively associated with NTG, but these associations did not retain statistical significance after Bonferroni correction (P < 0.05, Pc > 0.05). CONCLUSION: Our study showed a significant association between the GPDS1 locus and NTG, suggesting that there may be some genetic risk factor(s) in the development of NTG.

Aromatic substitution reaction of 2-chloropyridines catalyzed by microsomal glutathione S-transferase 1.

We investigated the substitution reaction of a series of 2-chloropyridine derivatives catalyzed by rat liver microsomal glutathione S-transferase 1. Various 2-chloropyridine derivatives were metabolized to the corresponding substituted glutathione conjugates via displacement of chlorine atom with glutathione. The reaction was affected by the electron-withdrawing strength and position of the substituents. Molecular orbital calculations on the change in Gibbs free energy between the initial and transition states verified the presence of a Meisenheimer complex and its influence on the reaction rate.

Identification of an orally active opioid receptor-like 1 (ORL1) receptor antagonist 4-{3-[(2R)-2,3-dihydroxypropyl]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl}-1-[(1S,3S,4R)-spiro[bicyclo[2.2.1]heptane-2,1'-cyclopropan]-3-ylmethyl]piperidine as clinical candidate.

Our efforts to optimize prototype opioid receptor-like 1 (ORL1) antagonist 1 led to the discovery of 4-{3-[(2R)-2,3-dihydroxypropyl]-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl}-1-[(1S,3S,4R)-spiro[bicyclo[2.2.1]heptane-2,1'-cyclopropan]-3-ylmethyl]piperidine 10. 10 showed potent ORL1 antagonistic activity, excellent selectivity over other opioid receptors, and in vivo efficacy after oral dosing. Currently clinical trials of 10 are underway.