Filgotinib Modulates Inflammation-Associated Peripheral Blood Protein Biomarkers in Adults with Active Rheumatoid Arthritis and Prior Inadequate Response to Methotrexate

INTRODUCTION

Our aim was to evaluate protein biomarker changes related to the administration of filgotinib, a Janus kinase (JAK) 1 preferential inhibitor, in patients with moderately to severely active rheumatoid arthritis (RA) with inadequate response to methotrexate.

METHODS

Plasma and serum samples were collected from patients enrolled in FINCH 1 (NCT02889796), a Phase 3 trial. Patients with stable backgrounds of methotrexate were randomly assigned once-daily oral filgotinib 200 or 100 mg, subcutaneous adalimumab 40 mg every 2 weeks (W), or placebo. Up to 35 biomarkers were analyzed at baseline, W4, and W12 with enzyme-linked immunosorbent assays and chemiluminescence and electrochemiluminescence assays.

RESULTS

At baseline, four distinct biomarker clusters were identified. The strongest intragroup correlations were in bone-cartilage resorption/inflammation and JAK/signal transducer and activator of transcription (STAT) signaling activity. At baseline, significant positive correlations were identified for cytokines with patient-reported pain and with patient measures of fatigue. Filgotinib reduced levels of cytokines associated with inflammation and cell migration as early as W4 and through W12. Compared to adalimumab, filgotinib induced significant reductions in bone-related turnover biomarkers, N-telopeptide of type 1 collagen and C-telopeptide 1, as well as biomarkers associated with baseline disease activity. No baseline predictors of therapeutic response to filgotinib were identified.

CONCLUSIONS

Filgotinib reduced peripheral protein biomarkers associated with JAK/STAT signaling, inflammatory signaling, immune cell migration, and bone resorption as soon as W4 in FINCH 1. Effects were dose-dependent and consistent with the clinical efficacy of filgotinib observed in FINCH 1. The changes in peripheral biomarkers associated with filgotinib treatment in methotrexate-experienced patients are consistent with changes observed in both methotrexate-naïve and biologic disease-modifying antirheumatic drug-experienced RA populations. These data demonstrate dose-dependent effects of preferential JAK1 inhibition by filgotinib on peripheral blood protein biomarkers in methotrexate-experienced patients with RA.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02889796.

Efficacy and Safety of Filgotinib in Patients with High Risk of Poor Prognosis Who Showed Inadequate Response to MTX: A Post Hoc Analysis of the FINCH 1 Study

INTRODUCTION

This exploratory analysis of FINCH 1 (NCT02889796) examined filgotinib (FIL) efficacy and safety in a subgroup of patients with rheumatoid arthritis (RA) and inadequate response to methotrexate (MTX; MTX-IR) who had four poor prognostic factors (PPFs).

METHODS

Patients with MTX-IR received placebo up to week (W)24 or FIL200 mg, FIL100 mg, or adalimumab up to W52; all received MTX. Efficacy and safety data were stratified by four PPFs versus fewer than four PPFs: seropositivity, high-sensitivity C-reactive protein (CRP) ≥ 6 mg/L, Disease Activity Score in 28 joints with CRP > 5.1, and erosions on X-rays.

RESULTS

At baseline, 687/1755 patients had four PPFs. At W12, whether with four PPFs or fewer than four PPFs, response rates on all American College of Rheumatology (ACR) measures were significantly greater with FIL200 and FIL100 versus placebo. At W52, FIL200 ACR20/50/70 response rates remained at least numerically higher versus adalimumab in both subgroups. At W52, FIL200 reduced modified total Sharp score (mTSS) change versus adalimumab in patients with four or fewer than four PPFs.

CONCLUSIONS

In high-risk (four PPFs) patients with MTX-IR RA, FIL200 and FIL100 showed similar reductions in disease activity versus placebo at W12 as in patients with fewer than four PPFs. mTSS in patients receiving FIL200 changed little from W24 to W52, while that in patients receiving FIL100 progressed comparably to patients who received adalimumab. Tolerability was comparable across treatment arms and subgroups.

Benefit of Filgotinib, a JAK1 Preferential Inhibitor, in Rheumatoid Arthritis Patients with Previous Rapid Radiographic Progression: Post Hoc Analysis of Two Trials

INTRODUCTION

We conducted a post hoc analysis of efficacy and safety of filgotinib stratified by estimated radiographic progression rate before baseline (BL) in patients with rheumatoid arthritis (RA) who had inadequate response to methotrexate (MTX; FINCH 1; NCT02889796) or were naïve to it (FINCH 3; NCT02886728).

METHODS

Radiographic progression rate was BL-Modified Total Sharp Score (mTSS) divided by RA duration (BL mTSS/year); estimated rapid radiographic progression (e-RRP) was BL change in mTSS/year ≥ 5; and estimated nonrapid radiographic progression (e-NRRP) was BL mTSS/year < 5. Efficacy and safety were compared between subgroups. All p-values are nominal.

RESULTS

In FINCH 1 and FINCH 3, 558/1755 (31.8%) and 787/1249 (63.0%) patients, respectively, had BL e-RRP. BL characteristics were generally similar between subgroups within each trial. At week (W) 24, in FINCH 1, proportions achieving a Disease Activity Score 28 for rheumatoid arthritis with C-reactive protein  < 2.6 were significantly greater with filgotinib 200 (FIL200) and 100 mg (FIL100) versus placebo among e-RRP and e-NRRP subgroups. In each study, proportions of FIL-treated patients achieving Clinical Disease Activity Index ≤ 2.8 and Simple Disease Activity Index ≤ 3.3 were similar between subgroups. In FINCH 3, disease activity measures were at least numerically improved among patients receiving FIL versus MTX monotherapy. At W24, mTSS changes from BL (CFB) were greater among patients with e-RRP in FINCH 1 and FINCH 3 versus e-NRRP (0.81 versus 0.19, p = 0.001; 0.67 versus 0.25, p = 0.31, respectively). At W52, in FINCH 1, mTSS CFBs were smaller among e-RRP patients treated with FIL200 (0.40; p < 0.001) and FIL100 (0.77; p = 0.024) versus adalimumab (ADA; 1.46). In FINCH 3 at W52, mTSS CFBs were significantly smaller with FIL200 versus MTX among e-RRP patients. Rates of treatment-emergent adverse events (AEs) were comparable between subgroups and across treatment arms.

CONCLUSIONS

Patients with previous e-RRP who received standard care tended to progress radiographically. FIL200 demonstrated persistent, consistent benefit for disease activity control among e-RRP and e-NRRP subgroups, and AE profiles were similar between subgroups. Although filgotinib efficacy was somewhat reduced among patients with e-RRP, filgotinib treatment slowed radiographic progression in both subgroups.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02889796, NCT02886728.

POS0704 EFFICACY AND SAFETY OF FILGOTINIB IN PATIENTS WITH INADEQUATE RESPONSE TO METHOTREXATE, WITH 4 OR <4 POOR PROGNOSTIC FACTORS: A POST HOC ANALYSIS OF THE FINCH 1 STUDY

Background

Patients (pts) with rheumatoid arthritis (RA) and poor prognostic factors1 (PPF) are at risk for progression without adequate treatment. Filgotinib (FIL) is a once daily Janus kinase 1 preferential inhibitor. In FINCH 1 (NCT02889796), FIL 200 mg (FIL200) was effective vs placebo (PBO) and noninferior to adalimumab (ADA) in pts with RA and inadequate response to methotrexate (MTX-IR); FIL200 and FIL 100 mg (FIL100) were well tolerated.2

Objectives

This post hoc, exploratory analysis examined efficacy and safety of FIL in MTX-IR pts with 4 or <4 PPF.

Methods

The FINCH 1 52-week (W), double-blind trial randomised MTX-IR pts with moderate–severe RA to FIL200 or FIL100, ADA, or PBO; all received background MTX. PBO pts were rerandomised, blinded, at W24 to FIL200 or FIL100. We examined pts with 4 PPF at baseline (BL): erosions on X-ray, seropositivity for rheumatoid factor or anticyclic citrullinated peptide, high-sensitivity C-reactive protein (hsCRP) ≥6 mg/L, and disease activity score in 28 joints with CRP (DAS28[CRP]) >5.1, along with those with <4 PPF. Efficacy included DAS28(CRP) <2.6 and modified Total Sharp Score (mTSS) change from baseline (CFB). Fisher’s exact test was used for DAS28(CRP); the mixed-effects model was used to generate least squares mean mTSS CFB. P values were nominal, not adjusted for multiplicity.

Results

At BL, of 1755 randomized, treated pts, 687 had 4 PPF, and 1068 had <4 PPF. Among pts with <4PPF, 804 [75%] had erosions, 810 [76%] were seropositive, 377 [35%] had hsCRP ≥6 mg/L, 638 [60%] had DAS28[CRP] >5.1). Pts with 4 vs <4 PPF were aged 53 vs 52 years, had RA duration 8.3 vs 7.4 years, DAS28(CRP) 6.3 vs 5.4, and SDAI 45.6 vs 37.7. In pts with 4 or <4 PPF, higher proportions receiving FIL200 or FIL100 achieved DAS28(CRP) <2.6 at W12 vs PBO (nominal P <.001); proportions with DAS28(CRP) <2.6 increased with FIL200, FIL100, or ADA at W52 (Figure 1). DAS28(CRP) responses for FIL200 at W52 were similar in 4 vs <4 PPF pts; FIL100 and ADA responses were numerically higher in <4 vs 4 PPF pts. At W24, mTSS CFB in pts with 4 PPF was 0.21, 0.23, 0.30, and 0.66 for FIL200, FIL100, ADA, and PBO (P <.05 for FIL200 and FIL100 vs PBO); corresponding changes in <4 PPF pts were 0.08, 0.10, 0.11, and 0.24 (P >.05). At W52, mTSS CFB in 4 PPF pts was 0.29, 0.84, and 0.80 for FIL200, FIL100, and ADA, respectively, and 0.14, 0.25, and 0.53 in <4 PPF pts. Rates of adverse events (AEs), including AEs of interest, were comparable for pts with 4 PPF and <4 PPF for all treatment arms (Table 1).

Table 1.

AEs and AEs of interest in BL 4 PPF and <4 PPF subgroups

4 PPF<4 PPFFIL200FIL100ADAPBO beforeFIL200FIL100ADAPBO(n = 191)(n = 189)(n = 126)W24 switch (n = 181)(n = 284)(n = 291)(n = 199)before W24 switch (n = 294)All AEs146 (76.4)136 (72.0)85 (67.5)90 (49.7)206 (72.5)214 (73.5)154 (77.4)164 (55.8)AEs of interestSerious infectious AE5 (2.6)4 (2.1)6 (4.8)2 (1.1)8 (2.8)9 (3.1)4 (2.0)2 (0.7)Opportunistic infections001 (0.8)0001 (0.5)0Active tuberculosis0000001 (0.5)0Herpes zoster1 (0.5)1 (0.5)1 (0.8)05 (1.8)3 (1.0)1 (0.5)2 (0.7)Hepatitis B or C01 (0.5)001 (0.5)01 (0.5)0MACE01 (0.5)01 (0.6)01 (0.3)1 (0.5)1 (0.3)VTE001 (0.8)1 (0.6)1 (0.4)001 (0.3)DVT001 (0.8)1 (0.6)0001 (0.3)PE00001 (0.4)000Malignancy0003 (1.7)2 (0.7)2 (0.7)2 (1.0)0(non-NMSC)GI perforation00001 (0.4)000

Values are n (%). ADA, adalimumab; AE, adverse event; BL, baseline; DVT, deep vein thrombosis; FIL100, filgotinib 100 mg; FIL200; filgotinib 200 mg; GI, gastrointestinal; MACE, major adverse cardiac event; NMSC, nonmelanoma skin cancer; PBO, placebo; PE, pulmonary embolism; PPF, poor prognostic factor; VTE, venous thromboembolism; W, week.

Conclusion

In high-risk (4 PPF) pts with MTX-IR RA, FIL200 and FIL100 showed similar reductions in disease activity vs PBO at W12 as in pts with <4 PPF; mTSS in FIL200 pts changed little from W24 to W52. Tolerability was comparable across treatment arms, regardless of presence of 4 or <4 PPF.

References

[1]Smolen JS et al. Ann Rheum Dis. 2020;79:685–99.

[2]Combe B et al. Ann Rheum Dis. 2021;80:848–58.

Acknowledgements

This study was funded by Gilead Sciences, Inc., Foster City, CA. Medical writing support was provided by Rob Coover, MPH, of AlphaScientia, LLC, San Francisco, CA, and was funded by Gilead Sciences, Inc., Foster City, CA. Funding for this analysis was provided by Gilead Sciences, Inc. The sponsors participated in the planning, execution, and interpretation of the research.

Disclosure of Interests

Bernard Combe Speakers bureau: AbbVie, Bristol-Myers Squibb, Celltrion, Eli Lilly, Gilead-Galapagos, Janssen, Merck Sharp & Dohme, Novartis, Pfizer, and Roche-Chugai, Consultant of: AbbVie, Bristol-Myers Squibb, Celltrion, Eli Lilly, Gilead-Galapagos, Janssen, Merck Sharp & Dohme, Novartis, Pfizer, and Roche-Chugai, Grant/research support from: Pfizer and Roche-Chugai, Yoshiya Tanaka Speakers bureau: AbbVie, Amgen, Astellas, AstraZeneca, Behringer-Ingelheim, Bristol-Myers, Chugai, Eisai, Eli Lilly, Gilead Sciences, Inc., Mitsubishi-Tanabe, and YL Biologics, Paid instructor for: AbbVie, Amgen, Astellas, AstraZeneca, Behringer-Ingelheim, Bristol-Myers, Chugai, Eisai, Eli Lilly, Gilead Sciences, Inc., Mitsubishi-Tanabe, and YL Biologics, Grant/research support from: AbbVie, Asahi-Kasei, Boehringer-Ingelheim, Chugai, Corrona, Daiichi-Sankyo, Eisai, Kowa, Mitsubishi-Tanabe, and Takeda, Maya H Buch Speakers bureau: AbbVie, Eli Lilly, Gilead Sciences, Inc., Merck-Serono, Pfizer, Roche, Sanofi, and UCB, Paid instructor for: AbbVie, Eli Lilly, Gilead Sciences, Inc., Merck-Serono, Pfizer, Roche, Sanofi, and UCB, Consultant of: AbbVie, Eli Lilly, Gilead Sciences, Inc., Merck-Serono, Pfizer, Roche, Sanofi, and UCB, Grant/research support from: AbbVie, Eli Lilly, Gilead Sciences, Inc., Merck-Serono, Pfizer, Roche, Sanofi, and UCB, Gerd Rüdiger Burmester Speakers bureau: AbbVie, Eli Lilly, Pfizer, and Gilead Sciences, Inc., Consultant of: AbbVie, Eli Lilly, Pfizer, and Gilead Sciences, Inc., Beatrix Bartok Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Alena Pechonkina Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Ling Han Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Kahaku Emoto Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences K.K., Shungo Kano Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences K.K., Thijs Hendrikx Employee of: Galapagos BV, Daniel Aletaha Speakers bureau: Bristol-Myers Squibb, Merck Sharp & Dohme, and UCB; AbbVie, Amgen, Celgene, Eli Lilly, Medac, Merck, Novartis, Pfizer, Roche, Sandoz, and Sanofi/Genzyme., Consultant of: AbbVie, Amgen, Celgene, Eli Lilly, Medac, Merck, Novartis, Pfizer, Roche, Sandoz, and Sanofi/Genzyme; Janssen, Grant/research support from: from AbbVie, Merck Sharp & Dohme, Novartis, and Roche

POS0664 RADIOGRAPHIC CHANGE IN PATIENTS WITH RHEUMATOID ARTHRITIS AND ESTIMATED BASELINE YEARLY PROGRESSION ≥5 OR <5: POST HOC ANALYSIS OF TWO PHASE 3 TRIALS OF FILGOTINIB

Background

In some patients (pts) with rheumatoid arthritis (RA), especially those with joint damage early in the disease, first-line methotrexate (MTX) treatment may not suffice to prevent further rapid radiographic progression (RRP).1 In FINCH 1 (NCT02889796), filgotinib 200 mg (FIL200) and 100 mg (FIL100) reduced change in modified total Sharp score (mTSS) vs placebo (PBO) in pts with RA and inadequate response to MTX (MTX-IR).2 In FINCH 3 (NCT02886728), FIL200 and FIL100 reduced change in mTSS vs MTX monotherapy (MTX mono) in MTX-naïve pts.3

Objectives

To evaluate, via post hoc analysis of 2 trials, filgotinib’s effects on radiographic progression vs MTX mono in pts with estimated baseline (BL) yearly progression ≥5 or <5 mTSS units/year.

Methods

The double-blind 52-week (W) FINCH 1 study randomised MTX-IR pts with moderate–severe active RA to FIL200 or FIL100, subcutaneous adalimumab (ADA) 40 mg, or PBO; at W24, PBO pts were rerandomised blinded to FIL200 or FIL100; all took stable background MTX.2 In FINCH 3, MTX-naïve pts were randomised, blinded, to FIL200 + MTX, FIL100 + MTX, FIL200 alone, or MTX mono for up to W52.3 This analysis examined subgroups by estimated BL yearly progression (BL mTSS/duration in years of RA diagnosis), based on ≥5 or <5 mTSS units/year,4 a threshold commonly used to define RRP. We assessed effects of filgotinib vs ADA or PBO in mTSS change from BL (CFB) at W24/W52 (using a mixed model for repeated measures) and percentages with no W24 progression (mTSS change ≤0, ≤0.5, ≤smallest detectable change [SDC], using Fisher’s exact test).

Results

At BL, 558/1755 MTX-IR and 787/1249 MTX-naïve pts had BL estimated yearly progression ≥5. Median mTSS in pts with BL yearly progression ≥5 and <5 was 53.25 vs 5.00 respectively in the MTX-IR trial and 6.00 vs 2.50 in the MTX-naïve trial. At W24, the mTSS CFB in pts with BL yearly progression ≥5 and <5 was 0.84 and 0.22 in MTX-IR pts taking PBO + MTX, and 0.67 and 0.25 in MTX-naïve pts taking MTX mono. At W52, in pts with BL yearly progression ≥5, FIL200 + MTX reduced mTSS change vs PBO + MTX in the MTX-IR trial and vs MTX mono in the MTX-naïve trial (Figure 1). At W24, among pts with estimated BL yearly progression ≥5, FIL200 + MTX increased odds of no progression (≤0.5 or ≤0) vs PBO + MTX in MTX-IR pts and vs MTX mono in MTX-naïve pts (Table 1).

Table 1.

Ratio of no radiographic progression at W24

FINCH 1: MTX-IRFIL200 + MTXFIL100 + MTXADA + MTXPBO + MTXBL yearly progression≥5(n = 138)<5(n = 267)≥5(n = 139)<5(n = 265)≥5(n = 91)<5(n = 180)≥5(n = 101)<5(n = 250)% with no progression (≤0.5)87.797.088.592.587.993.976.291.6OR2.22*2.97*2.40*1.12††††% with no progression (≤0)80.491.881.388.380.289.467.386.4OR2.00*1.752.11*1.19††††% with no progression (≤SDC [1.36])91.398.192.196.692.395.681.294.0OR2.43*3.35*2.70*1.82††††FINCH 3: MTX-naïveFIL200 + MTXFIL100 + MTXFIL200 monoMTXBL yearly progression≥5<5≥5<5≥5<5≥5<5(n = 221)(n = 134)(n = 121)(n = 63)(n = 115)(n = 58)(n = 224)(n = 132)% with no progression (≤0.5)86.994.083.593.789.689.778.687.9OR1.81*2.171.382.032.34*1.20††% with no progression (≤0)78.783.672.784.180.087.967.980.3OR1.75*1.251.261.31.89*1.79††% with no progression (≤SDC [1.53])93.797.891.796.895.796.689.395.5OR1.772.081.331.452.641.33††

MTX-IR ORs are FIL vs PBO + MTX; MTX-naïve are FIL vs MTX. *Nominal P<.05. †Not applicable.

ADA, adalimumab; FIL, filgotinib; IR, inadequate response; mTSS, modified total Sharp score; MTX, methotrexate; OR, odds ratio; SDC, smallest detectable change; W, week.

Conclusion

These data suggest filgotinib’s inhibition of radiographic progression was numerically greater than MTX monotherapy in RA pts with high estimated BL yearly progression. In those with a more moderate estimated rate of progression, filgotinib suppressed progression comparably to ADA and/or MTX.

References

[1]Smolen J et al. Ann Rheum Dis 2018;77:1566–1572.

[2]Combe B et al. Ann Rheum Dis 2021;80:848–858.

[3]Westhovens R et al. Ann Rheum Dis 2021;80:727–738.

[4]Vastesaeger N et al. Rheumatology. 2009;48:1114–1121.

Acknowledgements

This study was funded by Gilead Sciences, Inc., Foster City, CA. Medical writing support was provided by Rob Coover, MPH, of AlphaScientia, LLC, San Francisco, CA; and funded by Gilead Sciences, Inc., Foster City, CA. Funding for this analysis was provided by Gilead Sciences, Inc. The sponsors participated in the planning, execution, and interpretation of the research.

Disclosure of Interests

Yoshiya Tanaka Speakers bureau: AbbVie, Amgen, Astellas, AstraZeneca, Behringer-Ingelheim, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Gilead, Mitsubishi-Tanabe, and YL Biologics, Grant/research support from: AbbVie, Asahi-Kasei, Boehringer-Ingelheim, Chugai, Corrona, Daiichi Sankyo, Eisai, Kowa, Mitsubishi-Tanabe, and Takeda, Tatsuya Atsumi Paid instructor for: Gilead Sciences, Inc.; Mitsubishi Tanabe; Chugai; Astellas Pharma; Takeda; Pfizer; AbbVie: Eisai; Daiichi Sankyo; Bristol-Myers Squibb; UCB Japan Co. Ltd.; Eli Lilly Japan K.K., Otsuka Pharmaceutical Co., Ltd.; and Alexion Inc., Grant/research support from: Gilead Sciences, Inc.; Mitsubishi Tanabe; Chugai; Astellas Pharma; Takeda; Pfizer; AbbVie: Eisai; Daiichi Sankyo; Bristol-Myers Squibb; UCB Japan Co. Ltd.; Eli Lilly Japan K.K., Otsuka Pharmaceutical Co., Ltd.; and Alexion Inc., Daniel Aletaha Speakers bureau: AbbVie; Amgen; Celgene; Eli Lilly; Medac; Merck; Novartis; Pfizer; Roche; Sandoz; and Sanofi/Genzyme; Bristol-Myers Squibb, Merck Sharp & Dohme, and UCB, Consultant of: Janssen; AbbVie; Amgen; Celgene; Eli Lilly; Medac; Merck; Novartis; Pfizer; Roche; Sandoz; and Sanofi/Genzyme, Grant/research support from: AbbVie, Merck Sharp & Dohme, Novartis, and Roche, Robert B.M. Landewé Paid instructor for: AbbVie, AstraZeneca, Bristol-Myers Squibb, Eli Lilly, Galapagos NV, Novartis, Pfizer, and UCB, Consultant of: AbbVie, AstraZeneca, Bristol-Myers Squibb, Eli Lilly, Galapagos NV, Novartis, Pfizer, and UCB, Beatrix Bartok Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc, Alena Pechonkina Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Zhaoyu Yin Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Ling Han Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences, Inc., Kahaku Emoto Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences K.K., Shungo Kano Shareholder of: Gilead Sciences, Inc., Employee of: Gilead Sciences K.K., Vijay Rajendran Employee of: Galapagos BV, Tsutomu Takeuchi Speakers bureau: AbbVie, Ayumi Pharmaceutical Corporation, Bristol-Myers Squibb, Chugai, Daiichi Sankyo, Dainippon Sumitomo Eisai, Eli Lilly Japan, Mitsubishi-Tanabe, Novartis, Pfizer Japan, Sanofi, and Gilead Sciences, Inc., Consultant of: Astellas, Chugai, and Eli Lilly Japan, Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi Sankyo, Eisai, Mitsubishi-Tanabe, Shionogi, Takeda, and UCB Japan

Expression of monoacylglycerol lipase as a marker of tumour invasion and progression in malignant melanoma

BACKGROUND

Accumulating evidence suggests that the lipid lytic enzyme monoacylglycerol lipase (MAGL) promotes tumour invasion and metastasis through up-regulation of pro-tumorigenic signalling lipids in several tumour cell lines. However, the expression status of MAGL in clinical melanoma tissues and its clinicopathological significance remain unclear.

OBJECTIVE

To correlate the tumour expression status of MAGL with the clinicopathological information of patients with malignant melanoma.

METHODS

Polymerase chain reaction (PCR) array screening was performed, and the results were validated using immunocytochemical analysis of tumour and non-tumour melanocytic cell lines. Immunohistochemical staining for MAGL was performed for 74 melanoma samples, including 48 primary and 26 metastatic tumours, in which the expression of MAGL was determined by evaluating the percentage of MAGL-positive tumour cells and the MAGL staining intensity. Finally, we analysed the association of MAGL expression status with tumour progression, tumour thickness and vascular invasion of the primary lesion.

RESULTS

Immunocytochemical analysis revealed that MAGL was expressed in all 12 melanoma cell lines, but not in normal human epidermal melanocytes. In the immunohistochemical analysis, positive staining for MAGL was noted in 32 of 48 (64.5%) primary lesions, 14 of 17 (82.4%) lymph node metastatic lesions and 7 of 9 (77.8%) skin metastatic lesions. Metastatic tumours had a significantly higher staining intensity (P = 0.033 for lymph node, P = 0.010 for skin). In the analysis of primary lesions, higher MAGL expression correlated with greater tumour thickness (P = 0.015) and the presence of vascular invasion (P = 0.017). On further evaluation of MAGL-positive primary lesions, staining intensity of MAGL tended to be higher in deeper areas of the tumour mass.

CONCLUSIONS

The expression of MAGL in tumour cells reflects the aggressiveness of melanoma cells and may serve as a marker of tumour progression.

Baricitinib versus Placebo or Adalimumab in Rheumatoid Arthritis

BACKGROUND

Baricitinib is an oral, reversible inhibitor of the Janus kinases JAK1 and JAK2 that may have therapeutic value in patients with rheumatoid arthritis.

METHODS

We conducted a 52-week, phase 3, double-blind, placebo- and active-controlled trial in which 1307 patients with active rheumatoid arthritis who were receiving background therapy with methotrexate were randomly assigned to one of three regimens in a 3:3:2 ratio: placebo (switched to baricitinib after 24 weeks), 4 mg of baricitinib once daily, or 40 mg of adalimumab (an anti-tumor necrosis factor α monoclonal antibody) every other week. End-point measures evaluated after adjustment for multiplicity included 20% improvement according to the criteria of the American College of Rheumatology (ACR20 response) (the primary end point), the Disease Activity Score for 28 joints (DAS28), the Health Assessment Questionnaire-Disability Index, and the Simplified Disease Activity Index at week 12, as well as radiographic progression of joint damage as measured by the van der Heijde modification of the total Sharp score (mTSS) (range, 0 to 448, with higher scores indicating greater structural joint damage) at week 24.

RESULTS

More patients had an ACR20 response at week 12 with baricitinib than with placebo (primary end point, 70% vs. 40%, P<0.001). All major secondary objectives were met, including inhibition of radiographic progression of joint damage, according to the mTSS at week 24 with baricitinib versus placebo (mean change from baseline, 0.41 vs. 0.90; P<0.001) and an increased ACR20 response rate at week 12 with baricitinib versus adalimumab (70% vs. 61%, P=0.014). Adverse events, including infections, were more frequent through week 24 with baricitinib and adalimumab than with placebo. Cancers were reported in five patients (two who received baricitinib and three who received placebo). Baricitinib was associated with reductions in neutrophil counts and increases in levels of creatinine and low-density lipoprotein cholesterol.

CONCLUSIONS

In patients with rheumatoid arthritis who had had an inadequate response to methotrexate, baricitinib was associated with significant clinical improvements as compared with placebo and adalimumab. (Funded by Eli Lilly and Incyte; ClinicalTrials.gov number, NCT01710358 .).

Efficacy and Safety of Baricitinib in Japanese Patients with Active Rheumatoid Arthritis Receiving Background Methotrexate Therapy: A 12-week, Double-blind, Randomized Placebo-controlled Study

OBJECTIVE

To evaluate efficacy and safety, baricitinib [Janus kinase (JAK) 1/JAK2 inhibitor] was compared with placebo in Japanese patients with active rheumatoid arthritis (RA) despite background treatment with methotrexate (MTX).

METHODS

This was a phase IIB, double-blind, randomized, placebo-controlled study (clinicaltrials.gov: NCT01469013). Patients had moderate to severe active adult-onset RA despite stable treatment with MTX. Patients (n = 145) were randomized in a 2:1:1:1:1 ratio to placebo or 1 mg, 2 mg, 4 mg, or 8 mg oral baricitinib daily for 12 weeks. The primary analysis compared the combined 4/8-mg dose groups with placebo for the American College of Rheumatology (ACR) 20 response rate at 12 weeks. Other outcomes included additional measures of disease activity, physical function, laboratory abnormalities, and adverse events.

RESULTS

A significantly higher proportion of patients in the combined 4/8-mg baricitinib group (37/48, 77%) compared with the placebo group (15/49, 31%) had at least an ACR20 response after 12 weeks of treatment (p < 0.001). Significant improvements in disease activity, remission, and physical function were observed as early as Week 2 of treatment with baricitinib, particularly with daily doses of ≥ 4 mg. Only 1 patient receiving baricitinib discontinued because of an adverse event. Adverse event rates with baricitinib doses ≤ 4 mg daily were similar to placebo, but there was a higher incidence of adverse events and laboratory abnormalities in the 8-mg group.

CONCLUSION

In this phase II study, baricitinib was well tolerated and rapidly improved the signs, symptoms, and physical function of Japanese patients with active RA, supporting continued development of baricitinib (clinicaltrials.gov NCT01469013).

Earthquake dynamics. Mapping pressurized volcanic fluids from induced crustal seismic velocity drops

Volcanic eruptions are caused by the release of pressure that has accumulated due to hot volcanic fluids at depth. Here, we show that the extent of the regions affected by pressurized fluids can be imaged through the measurement of their response to transient stress perturbations. We used records of seismic noise from the Japanese Hi-net seismic network to measure the crustal seismic velocity changes below volcanic regions caused by the 2011 moment magnitude (M(w)) 9.0 Tohoku-Oki earthquake. We interpret coseismic crustal seismic velocity reductions as related to the mechanical weakening of the pressurized crust by the dynamic stress associated with the seismic waves. We suggest, therefore, that mapping seismic velocity susceptibility to dynamic stress perturbations can be used for the imaging and characterization of volcanic systems.

Comparisons among isolates of Sweet potato feathery mottle virus using complete genomic RNA sequences

We determined the complete or partial nucleotide sequences of eight Sweet potato feathery mottle virus (SPFMV) isolates and compared them with 12 other partial SPFMV sequences. The genome organization of the isolate Bungo (strain group C) was very different from those of isolates in the russet crack, ordinary (O), and east Africa groups. 10-O appeared to be a recombinant of isolates S and O, with a recombination site within the P1 gene. This study will help to provide a better understanding of the taxonomy and biology of SPFMV and how these features relate to virulence.

Annexin II overexpression correlates with stromal tenascin-C overexpression: a prognostic marker in colorectal carcinoma

BACKGROUND

Overexpression of annexin II, a calcium-dependent phospholipid-binding protein, has been reported in various carcinomas. One of its ligands is tenascin-C, an extracellular matrix glycoprotein with predominantly antiadhesive qualities that also has been reported to be a prognostic marker for several carcinomas. In the current study, the authors investigated the correlation between the overexpression of annexin II and tenascin-C in colorectal carcinoma.

METHODS

Western blot analysis of annexin II expression was examined in four human colorectal carcinoma cell lines. Using immunohistochemical methods, the authors also examined expression of annexin II and tenascin-C in 105 primary colorectal carcinoma cases.

RESULTS

Although annexin II was expressed in human colon carcinoma cell lines, there was no apparent correlation between its expression level and the metastatic potential of these cell lines. The authors observed overexpression of annexin II and tenascin-C proteins in 29.5% and 49.5%, respectively, of colorectal carcinoma cases. Overexpression of annexin II was found to be correlated significantly with histologic type, tumor size, depth of invasion, and pTNM stage, whereas tenascin-C overexpression was noted to be correlated significantly with histologic type, depth of invasion, lymphatic invasion, venous invasion, lymph node metastasis, and pTNM stage. Expression of annexin II was shown to be correlated significantly with that of tenascin-C. Multivariate analysis demonstrated that annexin II and tenascin-C cooverexpression was an independent factor of poor prognosis in patients with colorectal carcinoma.

CONCLUSIONS

The data from the current study suggest that both annexin II and tenascin-C are overexpressed in advanced colorectal carcinoma and that they may be related to the progression and metastatic spread of colorectal carcinoma.

Membrane lipid control of cytokinesis

In the final stage of cell division, cytokinesis constricts and then seals the plasma membrane between the two daughter cells. The constriction is powered by a contractile ring of actin filaments, and scission involves rearrangement of the lipid bilayer of the cell membrane. We have shown that the lipid phosphatidylethanolamine (PE), which normally resides in the internal leaflet of the bilayer, is exposed on the external leaflet of the cleavage furrow as a result of enhanced transbilayer movement of the phospholipids during cytokinesis. To investigate the role of PE in cytokinesis, we employed two different approaches: manipulation of cell surface PE by a PE-binding peptide and establishment of a mutant cell line specifically defective in PE biosynthesis. Both approaches provide evidence that surface exposure of PE is essential for disassembly of the contractile ring at the final stage of cytokinesis. Based on these findings, we proposed that the transbilayer redistribution of PE plays a critical role in mediating coordinated movements between the contractile ring and the plasma membrane that are required for the proper progression of cytokinesis.

Bcl-X expression in esophageal squamous cell carcinoma: association with tumor progression and prognosis

BACKGROUND AND OBJECTIVES

Bcl-2 family proteins are regulators of programmed cell death and important in the development and progression of human various tumors. The role of these proteins in the development, progression and differentiation of esophageal squamous cell carcinoma (ESCC) is unclear.

METHODS

We investigated the expression of Bcl-2, Bcl-X, and Bax using immunohistochemistry in 86 ESCCs, and scored the expression by the weighted score.

RESULTS

Bcl-2 expression related to pT category (P=0.043) and histological grade (P = 0.001). Bcl-X expression related to pT category (P = 0.003), pN category (P = 0.041) and the number of positive nodes (P = 0.036), and had a tendency to relate to histological grade (P = 0.086). Bax expression had a tendency to relate to pN category (P = 0.081). The inverse relationship between Bcl-2 and Bcl-X expression was detected (P = 0.001), while the positive one between Bcl-X and Bax expression was detected (P = 0.014). Patients with low Bcl-X weighted score had a significantly longer survival compared with those with high Bcl-X weighted score. Multivariate analysis revealed Bcl-X expression as the independent prognostic factors (P = 0.022).

CONCLUSION

These results imply that Bcl-2 family proteins, especially Bcl-X, may contribute to the progression in ESCC.

DNA cytofluorometric analysis of chondrocytes in human articular cartilages under normal aging or arthritic conditions

OBJECTIVE

Since most chondrocytes in articular cartilage are in the resting phase (G0) of the cell cycle, it has been difficult to investigate their cell kinetics using 3H-thymidine autoradiography, or immunohistochemistry. In the present study, DNA cytofluorometry, which is useful to analyse the cell kinetics even for such inactive cell populations as in the G0 phase, was applied to human chondrocytes of the articular cartilages under normal aging and pathologic conditions such as osteoarthritis (OA), rheumatoid arthritis (RA), and aseptic necrosis (AN).

DESIGN

The human articular cartilages for the study were obtained from autopsy and surgical materials. Fifty joints were used for the study of aging, 54 for the study of OA, 20 for studying RA, and 10 for AN study. The isolated chondrocytes were quickly prepared from fresh articular cartilages, using a combination method of enzymatic digestion with papain and collagenase, followed by mechanical cell separation by churning and homogenization.

RESULTS

The DNA histograms obtained by cytofluorometry with propidium-iodide staining showed that most chondrocytes had diploid DNA content (2c) in all cartilages studied, suggesting that they were in the G0 phase. However, there were a few chondrocytes having tetraploid DNA content (4c) in the normally aged articular cartilages, and there were some cells having DNA content between 2c and 4c in the diseased cartilages. The former cells were considered to be G0-phase cells of the 4c chondrocytes, while the latter cells were considered to be in the DNA synthetic (S) phase or G2-phase of the 2c chondrocytes. The frequency of 4c chondrocytes in aged cartilage was significantly increased, compared to that in the young cartilage. In contrast to the normal cartilage, the frequency of S- and G2-phase cells, which was expressed as the S- G2 index, in diseased cartilages (OA, RA and AN) was significantly high (P< 0.0001). In OA cartilage, the S-G2 index was much higher in the severe or moderate stage than in the mild stage, suggesting that the chondrocytes in clusters may actively proliferate.

CONCLUSION

These results showed that in normal articular cartilages most chondrocytes are in the G0 phase, while some became 4c polyploid cells, and that these G0-phase chondrocytes had a potential to proliferate under diseased conditions.

Annexin II overexpression correlates with stromal tenascin-C overexpression: a prognostic marker in colorectal carcinoma

BACKGROUND

Overexpression of annexin II, a calcium-dependent phospholipid-binding protein, has been reported in various carcinomas. One of its ligands is tenascin-C, an extracellular matrix glycoprotein with predominantly antiadhesive qualities that also has been reported to be a prognostic marker for several carcinomas. In the current study, the authors investigated the correlation between the overexpression of annexin II and tenascin-C in colorectal carcinoma.

METHODS

Western blot analysis of annexin II expression was examined in four human colorectal carcinoma cell lines. Using immunohistochemical methods, the authors also examined expression of annexin II and tenascin-C in 105 primary colorectal carcinoma cases.

RESULTS

Although annexin II was expressed in human colon carcinoma cell lines, there was no apparent correlation between its expression level and the metastatic potential of these cell lines. The authors observed overexpression of annexin II and tenascin-C proteins in 29.5% and 49.5%, respectively, of colorectal carcinoma cases. Overexpression of annexin II was found to be correlated significantly with histologic type, tumor size, depth of invasion, and pTNM stage, whereas tenascin-C overexpression was noted to be correlated significantly with histologic type, depth of invasion, lymphatic invasion, venous invasion, lymph node metastasis, and pTNM stage. Expression of annexin II was shown to be correlated significantly with that of tenascin-C. Multivariate analysis demonstrated that annexin II and tenascin-C cooverexpression was an independent factor of poor prognosis in patients with colorectal carcinoma.

CONCLUSIONS

The data from the current study suggest that both annexin II and tenascin-C are overexpressed in advanced colorectal carcinoma and that they may be related to the progression and metastatic spread of colorectal carcinoma.

Annexin II overexpression is correlated with poor prognosis in human gastric carcinoma

Annexins belong to a family of the calcium-dependent phospholipid binding proteins. They are also substrates of receptor tyrosine kinases. Overexpression of Annexin II, which has been reported in various carcinomas, is thought to be associated with cell proliferation, differentiation and cell-cell adhesion in the pathogenesis of carcinoma, but the functions of Annexins have not been fully elucidated. In this study, we investigated the role of Annexin II (p36) and its relationship with c-erbB-2 overexpression in gastric carcinoma. We studied Annexin II expression using Western blot analysis in 8 human gastric carcinoma cell lines and expression of Annexin II and c-erbB-2 using, immunohistochemistry in 153 primary gastric carcinomas. Western blot revealed that Annexin II was expressed in 8 human gastric carcinoma cell lines. It was more strongly expressed in the cell membrane than in the cytoplasm of tumor cells in primary gastric carcinoma tissues. Thirty-three percent of all cases were immunopositive for Annexin II, overexpression of which was more frequent in differentiated type (p = 0.0009), lymph node, metastasis (p = 0.0147) and venous invasion (p = 0.0092). Annexin II and c-erbB-2 overexpression were significantly correlated p = 0.0002) and patients with Annexin II had poorer prognoses (p = 0.0066). Multivariate analysis showed that immunopositivity of both Annexin II and c-erbB-2 was an independent and poor prognostic factor (p = 0.0037). In conclusion, Annexin II was overexpressed in advanced gastric carcinomas and it could contribute to the progression of gastric carcinoma.

Indication of splenectomy for gastric carcinoma involving the proximal part of the stomach

BACKGROUND/AIMS

The role of splenectomy in the surgical management of gastric carcinoma is controversial and there is no consensus of opinion regarding the therapeutic value of splenectomy. The aim of this study was to search for possible metastasis to lymph nodes in the splenic hilum or along the splenic artery to avoid unnecessary splenectomy and to determine its indication.

METHODOLOGY

The clinical records of 204 patients who underwent total gastrectomy combined with splenectomy for gastric carcinomas involving the proximal part of the stomach were analyzed.

RESULTS

The incidence of nodal involvement to the splenic hilum and/or along the splenic artery was 49 (24.0%) of 204 gastric carcinomas involving the proximal part of the stomach that underwent combined gastrectomy and splenectomy. The characteristics of gastric carcinoma with metastasis to these nodes included a larger tumor, deeper penetration (T3, 4 tumors), a number of lymph node metastasis, and infiltrative type. In T2 cases, all the tumors with cancerous involvement to these nodes showed intraoperative gross serosal change). When the tumor size was less than 40 mm, nodal metastatic rate to the splenic hilum and/or along the splenic artery was very low.

CONCLUSIONS

In conclusion, splenectomy should be conducted in T2 cases with gross serosal change and T3, 4 cases. With regard to tumor size, in the cases with a tumor whose size was less than 40 mm, it is possible to preserve the spleen in most cases. In the near future, splenectomy should be clarified precisely by randomized trials in advanced gastric carcinoma.

Failure of the expression of phospholipid hydroperoxide glutathione peroxidase in the spermatozoa of human infertile males

Phospholipid hydroperoxide glutathione peroxidase (PHGPx) was intensely expressed in mitochondria in the midpiece of human spermatozoa by immunostaining with anti-PHGPx monoclonal antibodies. The PHGPx not only reduced phospholipid hydroperoxide but also scavenged hydrogen peroxide in human spermatozoa. We found a dramatic decrease in the level of expression of PHGPx in the spermatozoa of some infertile males by immunoblotting with anti-PHGPx monoclonal antibodies. These individuals accounted for about 10% of the group of 73 infertile males that we examined. All seven patients with PHGPx-defective spermatozoa were classified as suffering from oligoasthenozoospermia, a defect in which both the number and the motility of spermatozoa are significantly below normal. Males with PHGPx-defective spermatozoa accounted for 26% of the 27 infertile males with oligoasthenozoospermia. No defects in expression of PHGPx in spermatozoa were observed in 31 fertile volunteers. After a 3-h incubation, the relative number of motile spermatozoa with low-level expression of PHGPx was significantly lower than that of spermatozoa with normal expression of PHGPx. The PHGPx-defective spermatozoa failed to incorporate rhodamine 123, revealing a loss of mitochondrial membrane potential. Ultrastructual analysis of mitochondria by electron microscopy demonstrated that the morphology of mitochondria in PHGPx-defective spermatozoa was abnormal. The results suggest that failure of the expression of mitochondrial PHGPx in spermatozoa might be one of the causes of oligoasthenozoospermia in infertile men.

Acridine orange induces binucleation in chondrocytes

OBJECTIVE

Although it is well known that binuclear cells commonly appear among the chondrocytes of normal cartilages as well as among neoplastic chondrocytes of chondrosarcomas, the mechanism of binucleation is still unclear. Therefore, this study was undertaken to clarify the mechanism of binucleation in chondrocytes, using primary culture cells of growth plate cartilage.

DESIGN

These chondrocytes were exposed to acridine orange (AO) which is a fluorescent dye for differentiating certain DNAs and RNAs in nuclei and cytoplasm, and which inhibits mitosis. After exposure to 0.5 microg/ml AO, for 0, 6, 24, 48, and 96 h, the following parameters were investigated: (1) cell growth rate (GR); (2) frequency of hyperdiploid cells (%HDC) by DNA cytofluorometry; (3) mitotic index (MI); (4) BrdU labeling index (LI); (5) frequency of binuclear cells (%BNC).

RESULTS

Compared with the control cells, which were cultured in AO-free medium, the GR was remarkably inhibited at 24 h. MI was also decreased from 6 to 24 h, and LI decreased at 48 h. However, these parameters were recovered at 96 h. The %HDC was increased from 6 to 96 h, and the %BNC was also increased to a maximum of six times that of the control cells at 96 h.

DISCUSSION

These results suggested that the binuclear cells observed among the cultured chondrocytes may be formed from G2 arrested cells by amitotic nuclear division, but not by mitosis without cytoplasmic division or cell fusion.

[Effectiveness of high-dose, intermittent 5'-DFUR therapy for advanced gastric cancer]

We report a case of advanced gastric cancer with multiple liver metastases and peritoneal dissemination. The patient was effectively treated with high-dose 5'-DFUR. A 52-year-old patient with advanced gastric cancer and multiple liver metastases, who showed a high serum level of CEA and CA19-9 underwent simple D1 gastrectomy. Thereafter, he received per os 1,200 mg/day of 5'-DFUR intermittently (5 days a week) and TAI every four months postoperatively. The serum levels of both CEA and CA19-9 fell dramatically to within the normal range and were maintained thereafter until the present. The size and number of the liver metastases dramatically decreased, judging from CT and angiography findings.

Preparation of non-fouling surface through the coating with core-polymerized block copolymer micelles having aldehyde-ended PEG shell

A new type of surface modification with reactive polymeric micelle was carried out for the creation of non-fouling surface. Amphiphilic poly(ethylene glycol)-b-poly(D,L lactide) (PEG/PLA) copolymers possessing acetal group at PEG-end and methacryloyl group at PLA-end were quantitatively synthesized via an anionic polymerization technique. A micelle of narrow distribution was prepared from the block copolymer. Acetal groups on the micelle surface were quantitatively converted into aldehyde group by an acid treatment. The methacryloyl group located in the core of the micelle was polymerized via radical polymerization to form core-polymerized micelle having reactive aldehyde groups on the surface. The core-polymerized reactive micelle was coated to a primary amino-containing polypropylene (PP) plate that was prepared by a plasma treatment. A reductive amination reaction was employed for a conjugation of the reactive core-polymerized micelle on the surface via a covalent linkage. The coating was evaluated by X-ray photoelectron spectroscopy, zeta-potential measurement, and the adsorption of bovine serum albumin, and compared with the PEG-coating under the same condition. The ratio of peak from &Cmacr;&z.sbnd;O bond to C&z.sbnd;&Cmacr;&z.sbnd;C bond indicated that the density of PEG on the surface was higher for the micelle coating than the linear PEG-coating. This is also confirmed by the zeta-potential measurement. By coating the amino-PP surface with micelle, the zeta-potential was remarkably decreased while the PEG-coating under the same condition decreased only appreciably, indicating that micelle coating efficiently masked the surface charge. Further, micelle-covered surface exhibited reduction of protein adsorption. The reduction of protein adsorption along with remarkably masked surface charge implies the high applicability of the micelle coatings to biomedical and bioanalytical applications.

Binuclear cells induced by acridine orange in giant cell tumor of bone

We have recently found the presence of many binuclear cells among isolated and smeared cells in giant cell tumor of the bone (GCT). These binuclear cells are possibly associated with the formation of multinuclear cells. Therefore, this study was undertaken to clarify the mechanism of binucleation in GCT, using primary culture cells exposed to acridine orange (AO) which is a fluorescent vital staining dye for the cytoplasm and nucleus and which inhibits mitosis. The cells were isolated from explants of fresh tumor materials obtained from two GCT patients (GCT1 and GCT2). These cells were cultured in Dulbecco's modified Eagle medium (DMEM) with 10% Fetal calf serum (FCS). After exposure to 0.5 microgram/ml AO, for 0, 6, 24, 48, 96 and 144 hours the following parameters were investigated: 1) cell growth rate (GR); 2) frequency of hyperdiploid cells (%HDC) by DNA cytofluorometry; 3) mitotic index (MI); 4) BrdU labeling index (LI); 5) frequency of binuclear cells (%BNC). Compared to the control cells which were cultured in AO-free medium, the GR of both GCT cells exposed to AO was remarkably inhibited. The MI was 0 from 24 to 144 hours. The %HDC was increased at 24 hours and was maintained high until 144 hours. The LI was temporarily increased at 6 hours, but was decreased at 48 hours. The %BNC was gradually increased. AO inhibited DNA synthesis and cell mitotic activity in cultured GCT cells and it finally caused inhibition of cell growth. However, the frequencies of G2 arrest cells and binuclear cells were increased. These results suggested that the binuclear cells in GCT may be formed from G2 arrest cells by amitotic nuclear division, but not by mitosis without cytoplasmic division, or by cell fusion.

Assessment of chemosensitivity in patients with malignant bone and soft tissue tumors using thallium-201 scintigraphy and doxorubicin binding assay

This study was performed to compare the accumulation of thallium (Tl)-201 which is correlated with malignancy and the doxorubicin binding ability, which is correlated with chemosensitivity, in nine patients who received preoperative chemotherapy with doxorubicin and cisplatin. Tl-201 scintigraphy was performed at 15 minutes (early image) and 3 hours (delayed image) after injection of 111 MBq of Tl-201. The change of degree of the radionuclide uptake between the early and delayed images was evaluated before and after preoperative chemotherapy. The doxorubicin binding ability (%DB) to nuclear DNA in living tumor cells isolated from biopsy materials was assessed by doxorubicin binding assay. The histologic response to preoperative chemotherapy was evaluated by the percentage of tumor necrosis. Before preoperative chemotherapy no changes of Tl-201 uptake between the early and delayed images was detected in any tumors. Five patients, who had no change of Tl-201 uptake after preoperative chemotherapy, showed a poor histologic response and had a %DB ranging from 10% to 70% (mean: 36.0%). The other four patients, who had a %DB greater than 90%, showed a good histologic response. All of these four patients had decreased Tl-201 uptake after preoperative chemotherapy. This study demonstrated that doxorubicin binding assay and midcourse Tl-201 scintigraphy are useful methods to assess the response to chemotherapy early in malignant bone and soft tissue tumors.

Nerve contact with muscle component in neuromuscular hamartoma

Neuromuscular hamartoma is a very rare soft tissue tumor, of which only 20 cases have been reported previously. None of these reports has described the relation between hamartomatous skeletal muscle and nerve fibers in the tumor. We experienced a patient with neuromuscular hamartoma arising at the brachial plexus. In this tumor, the localization of synaptophysin (SYP), S-100 protein (SP), neuron-specific enolase (NSE) neurofilament protein (NFP) and myoglobin (MG) was immunohistochemically detected. The results showed that SYP and MG were diffusely localized in the hamartomatous muscle fibers, SP in the schwann cells, and NSE and NFP in the axons of the hamartomatous nerve. Therefore, it is suggested that in the neuromuscular hamartoma, the structure of the neuromuscular junction may be similar to that in the motor end-plate of the normal muscle, but it may not be functional, because the hamartomatous muscles could not contract by nerve stimulation.

Relationship between doxorubicin binding ability and tumor volume decrease after chemotherapy in adult malignant soft tissue tumors in the extremities

We have previously reported that the doxorubicin (DOX) binding ability detected by the DOX (or adriamycin) binding assay closely correlated with the chemosensitivity of human osteosarcomas (1). We performed the present study to clarify the relationship between the DOX binding ability (%DB) and the histologic response, rate of decrease in tumor volume of malignant soft tissue tumors after preoperative chemotherapy and prognosis. Nine malignant soft tissue tumors (4 liposarcomas, 3 synovial sarcomas, one malignant fibrous histiocytoma (MFH) and one extraskeletal osteosarcoma (EOS)) which arose at the extremities of adult patients were analyzed by the DOX binding assay using freshly biopsied specimens. After preoperative chemotherapy including DOX or pirarubicin (THP), the rate of decrease in tumor volume was measured using magnetic resonance imaging, and the histologic response expressed as tumor necrosis to chemotherapy was also investigated. All the patients, apart for one, were continuously disease-free after treatment. One patient with EOS died of metastatic disease before surgery. The histologic response in 8 tumors without EOS was poor. The %DB of 5 tumors was greater than 80% (average: 95.90%), whereas that of 4 tumors was less than 80% (average: 38.33%). Although there was no correlation between the %DB and the histologic response, or prognosis, a significantly positive correlation was found between the %DB and the rate of decrease in tumor volume (r = 0.7455, p < 0.05). These results suggest that in malignant soft tissue tumors, the rate of decrease in tumor volume after chemotherapy might be a better indicator for chemosensitivity than the histologic response and also that the DOX binding ability might be a good predictor for chemosensitivity before chemotherapy.

Relationship between binuclear and multinuclear cells in giant cell tumor of bone

Giant cell tumor of bone (GCT) consists of stromal and multinuclear type tumor cells. Although most people believe that the stromal cells are mononuclear, we recently found the existence of many binuclear cells among stromal cells using DNA cytofluorometric examination. This study, using 18 tumors of GCT was conducted to elucidate the cell biological significance of the binuclear cell, especially its relationship to multinuclear cell formation or tumor cell proliferation. The investigation was carried out by means of DNA-RNA cytofluorometry with acridine orange (AO) and histological method. Using fluorescence microscopic observation, we counted the numbers of both mononuclear and binuclear cells and calculated the index of % BNC, which expresses the frequency (percentage) of binuclear cells in a population of mononuclear and binuclear cells. The index of % S-G2 obtained by DNA-RNA cytofluorometry showed the frequency (percentage) of mononuclear cells in the S and G2 phases of the cell cycle. In the histological study, we counted the numbers of multinuclear giant cells with more than 3 nuclei in the cytoplasm and stromal cells including mononuclear and binuclear cells and calculated MNS/SC, which showed the percentage of multinuclear cells in the stromal cells in the microscopic field. Eight tumors showed a value of % BNC greater than 10% and 2 had a value of 40%. The index of % BNC significantly correlated with the average value of MNC/SC in all tumors. There was no significant correlation between % BNC and the average value of % S-G2, in 18 tumors although 4 tumors having a % BNC value greater than 20% showed a % S-G2 value greater than 12% in 18 tumors. These results revealed the presence of many binuclear cells among stromal cells of GCT and suggested that these binuclear cells might be formed in association with the active proliferation of mononuclear cells and closely relate to the formation of multinuclear giant cells.

An essential role for a membrane lipid in cytokinesis. Regulation of contractile ring disassembly by redistribution of phosphatidylethanolamine

Phosphatidylethanolamine (PE) is a major membrane phospholipid that is mainly localized in the inner leaflet of the plasma membrane. We previously demonstrated that PE was exposed on the cell surface of the cleavage furrow during cytokinesis. Immobilization of cell surface PE by a PE-binding peptide inhibited disassembly of the contractile ring components, including myosin II and radixin, resulting in formation of a long cytoplasmic bridge between the daughter cells. This blockade of contractile ring disassembly was reversed by removal of the surface-bound peptide, suggesting that the PE exposure plays a crucial role in cytokinesis. To further examine the role of PE in cytokinesis, we established a mutant cell line with a specific decrease in the cellular PE level. On the culture condition in which the cell surface PE level was significantly reduced, the mutant ceased cell growth in cytokinesis, and the contractile ring remained in the cleavage furrow. Addition of PE or ethanolamine, a precursor of PE synthesis, restored the cell surface PE on the cleavage furrow and normal cytokinesis. These findings provide the first evidence that PE is required for completion of cytokinesis in mammalian cells, and suggest that redistribution of PE on the cleavage furrow may contribute to regulation of contractile ring disassembly.

Intracellular binding sites of acridine orange in living osteosarcoma cells

There have been many reports concerning the intracellular binding sites of acridine orange (AO), although the actual localization of AO in living cells remains controversial. This study was undertaken to clarify the intracellular localization of AO in living mouse osteosarcoma cells by cytochemical staining. A mouse osteosarcoma cell line (MOS) was cultured and continuously exposed to 0.5 microgram/ml of AO. The intracellular localization and stainability of AO the living tumor cells was morphologically detected by a high resolution fluorescence microscope. To detect the intracellular microstructure, cytochemical staining with rhodamin 123 for mitochondria, acid phosphatase for lysosome, Sudan-black for fat vesicle and toluidine blue for glucosaminoglycan were performed using fixed cells. The results showed that both the nucleus and cytoplasm of tumor cells at 10 minutes after exposure to 0.5 microgram/ml of AO emitted green fluorescence, which was especially intense in the nucleolus, but not brilliant in the nucleus and was granular orange to red fluorescence in the perinuclear particles. This stainability of AO was different from that of rhodamin 123, Sudan-black or toluidine blue, but similar to that of acid phosphatase. Based on these results, we conclude that the green fluorescence may have derived from AO binding to double stranded RNA, not to DNA, and that orange fluorescence may have derived from aggregated AO binding to lysosome.

Isolation of a Chinese hamster ovary cell mutant defective in intramitochondrial transport of phosphatidylserine

A CHO-K1 cell mutant with a specific decrease in cellular phosphatidylethanolamine (PE) level was isolated as a variant resistant to Ro09-0198, a PE-directed antibiotic peptide. The mutant was defective in the phosphatidylserine (PS) decarboxylation pathway for PE formation, in which PS produced in the endoplasmic reticulum is transported to mitochondria and then decarboxylated by an inner mitochondrial membrane enzyme, PS decarboxylase. Neither PS formation nor PS decarboxylase activity was reduced in the mutant, implying that the mutant is defective in some step of PS transport. The transport processes of phospholipids between the outer and inner mitochondrial membrane were analyzed by use of isolated mitochondria and two fluorescence-labeled phospholipid analogs, 1-palmitoyl-2-[N-[6(7-nitrobenz-2-oxa-1, 3-diazol-4-yl)amino]caproyl]-PS (C6-NBD-PS) and C6-NBD-phosphatidylcholine (C6-NBD-PC). On incubation with the CHO-K1 mitochondria, C6-NBD-PS was readily decarboxylated to C6-NBD-PE, suggesting that the PS analog was partitioned into the outer leaflet of mitochondria and then translocated to the inner mitochondrial membrane. The rate of decarboxylation of C6-NBD-PS in the mutant mitochondria was reduced to approximately 40% of that in the CHO-K1 mitochondria. The quantity of phospholipid analogs translocated from the outer leaflet of mitochondria into inner mitochondrial membranes was further examined by selective extraction of the analogs from the outer leaflet of mitochondria. In the mutant mitochondria, the translocation of C6-NBD-PS was significantly reduced, whereas the translocation of C6-NBD-PC was not affected. These results indicate that the mutant is defective in PS transport between the outer and inner mitochondrial membrane and provide genetic evidence for the existence of a specific mechanism for intramitochondrial transport of PS.

Antisense epidermal growth factor receptor delivered by adenoviral vector blocks tumor growth in human gastric cancer

Epidermal growth factor receptor (EGFR) protein overexpression is commonly found in human gastric cancer, and its gene amplification is known to correlate with poor prognosis in gastric cancer patients. With regard to therapy trials targeting EGFR, it has been reported that stable transfection of EGFR antisense or treatment with antibody against EGFR results in growth suppression of human cancer cells that express high levels of EGFR. We have designed an adenovirus-expressing antisense EGFR and have investigated its effect on the growth of gastric cancer in vitro and in vivo. Following infection with EGFR antisense RNA-expressing adenovirus (Ad-EAS), the cell surface EGFR protein levels of infected cancer cells were markedly reduced, and the in vitro growth of Ad-EAS-infected cells was significantly inhibited relative to control-infected cells in all three gastric cancer cell lines (AGS, KKLS, and MKN28) studied here (P < .0002). In a nude mouse subcutaneous tumor system, in vivo tumor growth of MKN28 was significantly inhibited after Ad-EAS treatment, and inhibition on day 48 was 93% by volume compared with that of untreated controls. These results suggest that an adenoviral vector system targeting the down-regulation of EGFR could be a good candidate for the therapy of gastric cancers that overexpress EGFR.

Membrane phospholipid dynamics during cytokinesis: regulation of actin filament assembly by redistribution of membrane surface phospholipid

To study molecular motion and function of membrane phospholipids, we have developed various probes which bind specifically to certain phospholipids. Using a novel peptide probe, RoO9-0198, which binds specifically to phosphatidylethanolamine (PE) in biological membranes, we have analyzed the cell surface movement of PE in dividing CHO cells. We found that PE was exposed on the cell surface specifically at the cleavage furrow during the late telophase of cytokinesis. PE was exposed on the cell surface only during the late telophase and no alteration in the distribution of the plasma membranebound peptide was observed during the cytokinesis, suggesting that the surface exposure of PE reflects the enhanced transbilayer movement of PE at the cleavage furrow. Furthermore, cell surface immobilization of PE induced by adding of the cyclic peptide coupled with streptavidin to prometaphase cells effectively blocked the cytokinesis at late telophase. The peptide-streptavidin complex bound specifically to cleavage furrow and inhibited both actin filament disassembly at cleavage furrow and subsequent plasma membrane fusion. Binding of the peptide complex to interphase cells also induced immediate disassembly of stress fibers followed by assembly of cortical actin filaments to the local area of plasma membrane where the peptide complex bound. The cytoskeletal reorganizations caused by the peptide complex were fully reversible; removal of the surface-bound peptide complex by incubating with PE-containing liposome caused gradual disassembly of the cortical actin filaments and subsequent formation of stress fibers. These observations suggest that the redistribution of plasma membrane phospholipids act as a regulator of actin cytoskeleton organization and may play a crucial role in mediating a coordinate movement between plasma membrane and actin cytoskeleton to achieve successful cell division.

Effects of docosahexaenoic and arachidonic acids on the synthesis and distribution of aminophospholipids during neuronal differentiation of PC12 cells

We have shown previously that docosahexaenoic acid (DHA) promotes and arachidonic acid (AA) suppresses neurite outgrowth of PC12 cells induced by nerve growth factor (NGF) and that incorporation of [3H]ethanolamine into phosphatidylethanolamine (PE) is suppressed in PC12 cells by AA while DHA has no effect. In the present study, the effects of these fatty acids on PE synthesis via decarboxylation of phosphatidylserine (PS), another pathway of PE synthesis, and distribution of aminophospholipids were examined. Incorporation of [3H]serine into PS and PE was elevated in the course of NGF-induced differentiation and was further stimulated significantly by DHA, but not by AA. [3H]Ethanolamine uptake by PC12 cells was significantly suppressed by AA but not by DHA while these fatty acids did not affect [3H]serine uptake, indicating that the suppression by AA of [3H]ethanolamine incorporation into phosphatidylethanolamine is attributable, at least in part, to a reduction in [3H]ethanolamine uptake. The distribution of PE in the outer leaflet of plasma membrane decreased during differentiation, which is known to be accompanied by an increase in the surface area of plasma membrane. Supplementation of PC12 cells with DHA or AA did not affect the distribution of aminophospholipids. Thus, DHA and AA affected aminophospholipid synthesis and neurite outgrowth differently, but not the transport and distribution of aminophospholipids, while the PE concentration in the outer leaflet of the plasma membrane decreased in association with morphological changes in PC12 cells induced by NGF.

Mitochondrial phospholipid hydroperoxide glutathione peroxidase plays a major role in preventing oxidative injury to cells

Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is synthesized as a long form (L-form; 23 kDa) and a short form (S-form; 20 kDa). The L-form contains a leader sequence that is required for transport to mitochondria, whereas the S-form lacks the leader sequence. A construct encoding the leader sequence of PHGPx tagged with green fluorescent protein was used to transfect RBL-2H3 cells, and the fusion protein was transported to mitochondria. The L-form of PHGPx was identified as the mitochondrial form of PHGPx and the S-form as the non-mitochondrial form of PHGPx since preferential enrichment of mitochondria for PHGPx was detected in M15 cells that overexpressed the L-form of PHGPx, whereas no similar enrichment was detected in L9 cells that overexpressed the S-form. Cell death caused by mitochondrial injury due to potassium cyanide (KCN) or rotenone (chemical hypoxia) was considerably suppressed in the M15 cells, whereas the L9 cells and control RBL-2H3 cells (S1 cells, transfected with the vector alone) succumbed to the cytotoxic effects of KCN. Flow cytometric analysis showed that mitochondrial PHGPx suppressed the generation of hydroperoxide, the loss of mitochondrial membrane potential, and the loss of plasma membrane integrity that are induced by KCN. Mitochondrial PHGPx might prevent changes in mitochondrial functions and cell death by reducing intracellular hydroperoxides. Mitochondrial PHGPx failed to protect M15 cells from mitochondrial injury by carbonyl cyanide m-chlorophenylhydrazone, which directly reduces membrane potential without the generation of hydroperoxides. M15 cells were more resistant than L9 cells to cell death caused by direct damage to mitochondria and to extracellular oxidative stress. L9 cells were more resistant to tert-butylhydroperoxide than S1 cells, whereas resistance to t-butylhydroperoxide was even more pronounced in M15 cells than in L9 cells. These results suggest that mitochondria might be a target for intracellular and extracellular oxidative stress and that mitochondrial PHGPx, as distinct form non-mitochondrial PHGPx, might play a primary role in protecting cells from oxidative stress.

Characterization of Grafted Poly(ethylene glycol) on Si Wafers Using Scanning Probe Microscopy

The uniformity and surface topography of grafted poly(ethylene glycol) (PEG) coatings were characterized at the microscale as a function of grafting temperature (grafting density) using scanning probe microscopy. Images of PEG-coated silicon wafers show isolated domains which decrease in size and increase in surface density with increasing grafting temperature. Domain sizes appeared to correlate with the polarity of the solvent used for imaging. Roughness measurements of the PEG layers were obtained. The results are relevant in relation to the biomedically significant ability of PEG coatings to mask surface features such as charge detected via zeta potential measurements. Copyright 1998 Academic Press.

Characteristics and clinical outcome of proximal-third gastric cancer

BACKGROUND

It is generally accepted that the prognosis of patients with proximal gastric cancer (PGC) is worse than that of patients with more distal gastric cancer.

STUDY DESIGN

The aim of this study was to compare the clinical features and outcomes of PGC with those of middle- and distal-third gastric cancers. A total of 646 primary gastric cancers was analyzed as a retrospective study.

RESULTS

Proximal gastric cancer occurred in 21.8% of the 646 cancers analyzed, and approximately 21% of PGCs had esophageal invasion. The 5-year survival rate for patients with PGC was significantly lower than that of patients with more distal tumors. When the PGC group was divided into patients with esophageal invasion and without esophageal invasion, patients with esophageal invasion had significantly worse outcomes. When corrected for depth of invasion, lesions with esophageal invasion had significantly worse outcomes than those of other sites in T2 curative cancers. Proximal gastric cancer with esophageal invasion was characterized by a larger tumor, deeper penetration, and a higher incidence of lymph node metastasis compared with tumors in other sites, and in multivariate analysis of all curative cases, these variables were independent prognostic factors for survival. The frequency of positive proximal margins of PGC was higher than those of other sites.

CONCLUSIONS

The relatively poor prognosis associated with PGC is mainly from advanced tumor stages of esophageal invasion. Early detection is the most important strategy to improve the survival of patients with PGC. In addition, aggressive lymph node dissection and chemotherapy for esophageal invasion should be considered even if the tumor invasion is moderate (T2 tumor), and a tumor-free margin is important.

Induction of apoptosis by phosphatidylserine

Treatment of Chinese hamster ovary (CHO) cells with phosphatidylserine (PS) caused cell death in a dose-dependent manner. Other phospholipids, such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidic acid, had no effect on cell viability. The cells incubated with PS became round and underwent a dramatic reduction of cellular volume while maintaining the membrane containment of cellular contents. The PS-treatment induced chromatin condensation and extensive DNA fragmentation, with a pattern characteristic of internucleosomal fragmentation on agarose gel electrophoresis. These results indicate that PS-treatment induces apoptosis of CHO cells. This apoptosis-inducing activity was highly specific for PS, and neither of the synthetic PS analogs 1,2-diacyl-sn-glycero-3-phospho-D-serine (D-PS) and 2,3-diacyl-sn-glycero-1-phospho-L-serine induced apoptosis. Analysis using fluorescence-labeled phospholipids showed that both PS and D-PS were taken up equally and then transported to intracellular membranes, suggesting that the PS-specific induction of apoptosis was not the result of its specific internalization. These observations suggest that certain molecules which may recognize the stereo-specific configuration of PS are involved in the apoptotic process triggered by PS.