Continuation, reduction, or withdrawal of tofacitinib in patients with rheumatoid arthritis achieving sustained disease control: a multicenter, open-label, randomized controlled trial / 中华医学杂志(英文版)

BACKGROUND@#Rheumatoid arthritis (RA), a chronic systemic autoimmune disease, is characterized by synovitis and progressive damage to the bone and cartilage of the joints, leading to disability and reduced quality of life. This study was a randomized clinical trial comparing the outcomes between withdrawal and dose reduction of tofacitinib in patients with RA who achieved sustained disease control.@*METHODS@#The study was designed as a multicenter, open-label, randomized controlled trial. Eligible patients who were taking tofacitinib (5 mg twice daily) and had achieved sustained RA remission or low disease activity (disease activity score in 28 joints [DAS28] ≤3.2) for at least 3 months were enrolled at six centers in Shanghai, China. Patients were randomly assigned (1:1:1) to one of three treatment groups: continuation of tofacitinib (5 mg twice daily); reduction in tofacitinib dose (5 mg daily); and withdrawal of tofacitinib. Efficacy and safety were assessed up to 6 months.@*RESULTS@#Overall, 122 eligible patients were enrolled, with 41 in the continuation group, 42 in the dose-reduction group, and 39 in the withdrawal group. After 6 months, the percentage of patients with a DAS28-erythrocyte sedimentation rate (ESR) of <3.2 was significantly lower in the withdrawal group than that in the reduction and continuation groups (20.5%, 64.3%, and 95.1%, respectively; P  < 0.0001 for both comparisons). The average flare-free time was 5.8 months for the continuation group, 4.7 months for the dose reduction group, and 2.4 months for the withdrawal group.@*CONCLUSION@#Withdrawal of tofacitinib in patients with RA with stable disease control resulted in a rapid and significant loss of efficacy, while standard or reduced doses of tofacitinib maintained a favorable state.@*TRIAL REGISTRATION@#Chictr.org, ChiCTR2000039799.

Benzo[b]tryptanthrin inhibits MDR1, topoisomerase activity, and reverses adriamycin resistance in breast cancer cells.

Tryptanthrin is an indoloquinazoline alkaloid isolated from indigo. Tryptanthrin and its benzo-annulated derivative, benzo[b]tryptanthrin, inhibit both topoisomerases I (topo I) and II (topo II) and cause cytotoxicity in several human cancer cell lines. From diverse assessment methods, including cleavage complex stabilization, comet, DNA unwinding/intercalation, topo II ATPase inhibition, ATP competition for topo II, and wound-healing assays, we determined that the mode of action of benzo[b]tryptanthrin is as a DNA non-intercalative and ATP-competitive topo I and II dual catalytic inhibitor. Benzo[b]tryptanthrin induced apoptosis through the cleavage of caspase-3 and PARP in HCT15 colon cancer cells. Additionally, benzo[b]tryptanthrin reversed adriamycin resistance by down-regulation of multidrug resistance protein 1 (MDR1) in adriamycin-resistant MCF7 breast cancer cells (MCF7adr) with more potent inhibitory activity than tryptanthrin. Taken together, derivatization by benzo-annulation of tryptanthrin ameliorated the MDR-reversing effect of tryptanthrin and may pave the way to the discovery of a novel potent adjuvant agent for chemotherapy.

Synthesis of 6-deoxymollugins and their inhibitory activities on tyrosinase.

A series of 6-deoxymollugins were prepared five steps from benzaldehyde and its derivatives via phenylboronic acid-catalyzed chromenylation as a key step. Their inhibitory activities against tyrosinase from mushroom were evaluated to show that the parent, methyl 2,2-dimethyl-2H-benzo[h]chromene-5-carboxylate (9a) showed best and promising inhibitory activity at IC50 = 18.3 µM.

Synthesis and properties of annulated 2-(Azaar-2-yl)- and 2,2'-Di(azaar-2-yl)-9,9'-spirobifluorenes.

A series of 9,9'-spirobifluorene-derived N-heterocycles were prepared by the reactions of 8,9-dihydrospiro(benzo[b]fluorene-11,9'-fluoren)-6(7H)-one and 8,8',9,9'-tetrahydro-11,11'-spirobi(benzo[b]fluorene)-6,6'(7H,7'H)-dione with a series of 2-amino-arenecarbaldehydes such as 2-aminobenzaldehyde, 2-aminonicotinealdehyde, 1-amino-2-naphthaldehyde, and 8-aminoquinoline-7-carbaldehyde. In addition to the absorption maxima based on the parent 9,9'-spirobifluorene skeleton in the 225-234, 239-280, 296-298, and 308-328 nm regions, the absorptions due to the π-π* transitions of the heterocycles were observed in the 351-375 nm region in the UV absorption spectra. All the compounds showed strong photoluminescences in the 390-430 nm region.

Synthesis of benzo-annulated tryptanthrins and their biological properties.

A series of benzo-annulated derivatives of tryptanthrin were prepared and their optical and redox properties were studied. Tryptanthrin and its benzo-annulated derivatives showed selective inhibitory activity on topo I with an increase of activity on topo II by benzo-annulation on quinazolin-4(3H)-one moiety. Although the benzo-annulation on quinazolin-4(3H)-one ring did not affect significantly on the inhibitory activities against topo I and II, the benzoannulation on indolin-3-one ring affected the inhibitory activity very much especially by linear annulation. Cytotoxicities were not significantly changed upon benzoannulation, which were not directly related either to the inhibitory activities against topo I and II or to the reduction potentials.

Citreorosein inhibits production of proinflammatory cytokines by blocking mitogen activated protein kinases, nuclear factor-κB and activator protein-1 activation in mouse bone marrow-derived mast cells.

Citreorosein (CIT), an anthraquinone component of Polygoni cuspidati (P. cuspidati) radix, suppressed gene expression of proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß in mouse bone marrow-derived mast cells (BMMCs) stimulated with phorbol 12-myristate 13-acetate (PMA) plus the calcium ionophore A23187. To investigate the molecular mechanisms underlying CIT inhibition of the pro-inflammatory cytokine production, its effects on the activation of both nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs) were assessed. CIT attenuated phosphorylation of the MAPKs including extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAP kinase and c-Jun NH(2)-terminal kinase (JNK). Furthermore, CIT strongly inhibited DNA binding activity of NF-κB through the inhibition of phosphorylation and degradation of inhibitor of kappaB (IκB) as well as activator protein-1 (AP)-1 through the reduction of phosphorylation of c-Jun. These results demonstrate that CIT inhibits proinflammatory cytokines production through the inhibition of both MAPKs and AKT-mediated IκB kinase (IKK) phosphorylation and subsequent inhibition of transcription factor NF-κB activation, thereby attenuating the production of proinflammatory cytokines.

A facile synthesis of emodin derivatives, emodin carbaldehyde, citreorosein, and their 10-deoxygenated derivatives and their inhibitory activities on µ-calpain.

A new procedure for the preparation of emodin carbaldehyde and citreorosein was described, in which, ω,ω'-dibromomethylemodin triacetate was prepared as a key intermediate by NBSmediated bromination of 1,3,8-triacetylemodin. Reduction of emodin and citreorosein with SnCl(2) in a 1:1 mixture of HOAc and HCl afforded the corresponding anthrones in 90% and 92% yield, respectively, while the corresponding 10-desoxyemodin carbaldehyde was prepared by MnO(2) oxidation of 10-desoxycitreorosein. 10-Desoxycitreorosein and emodin carbaldehyde showed feasible µ-calpain inhibitory activities with IC(50) values of 20.15 and 25.77 M, respectively.

Recent advances in the studies on luotonins.

Luotonins are alkaloids from the aerial parts of Peganum nigellastrum Bunge. that display three major skeleton types. Luotonins A, B, and E are pyrroloquinazolino-quinoline alkaloids, luotonins C and D are canthin-6-one alkaloids, and luotonin F is a 4(3H)-quinazolinone alkaloid. All six luotonins have shown promising cytotoxicities towards selected human cancer cell lines, especially against leukemia P-388 cells. Luotonin A is the most active one, with its activity stemming from topoisomerase I-dependent DNA-cleavage. Such intriguing biological activities and unique structures have led not only to the development of synthetic methods for the efficient synthesis of these compounds, but also to interest in structural modifications for improving the biological properties. Recent progress in the study of luotonins is covered.

2,2-dimethyl-2H-pyran-derived alkaloids I. Practical synthesis of acronycine and benzo[b]acronycine and their biological properties.

The 2,2-dimethyl-2H-pyran-derived alkaloids acronycine and its demethylated congeners were prepared in three steps from anthranilic acid and phloroglucinol. The phenylboronic acid-mediated interamolecular cyclization reaction of 1,3-dihydroxyacridone and 3-methylbut-2-enal was employed as a key step, which was also applied to the synthesis of related cytotoxic benzo[b]acronycine. Inhibitory activities of the compounds prepared on topoisomerase I and II as well as their cytotoxicities were evaluated. Cytotoxicity of 2 is closely related to the strong inhibitory activity against topo II at 20 microM level.

Safety and efficacy of T-614 in the treatment of patients with active rheumatoid arthritis: a double blind, randomized, placebo-controlled and multicenter trial / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>A novel anti-rheumatic drug, T-614, has been shown to have an anti-inflammatory effect and to improve abnormal immunological findings in rheumatoid arthritis (RA). To assess the safety and efficacy of T-614 versus placebo in patients with active RA we conducted a 24-week clinical study in 280 Chinese patients.</p><p><b>METHODS</b>In a multicenter, randomized, double blind, placebo controlled study, 280 patients were randomly assigned to receive placebo (n = 95) or T-614 at 50 mg (n = 93) or 25 mg (n = 92) daily. Active disease was defined by 4 of the following 5 criteria: >or= 5 tender joints, >or= 3 swollen joints, morning stiffness lasting for >or= 60 minutes, and Westergren erythrocyte sedimentation rate (ESR) >or= 28 mm/h, the assessment of pain at the rest by patient as moderate or severe. Clinical and laboratory parameters were analyzed at baseline, 2, 4, 6, 12, 18 and 24 weeks. The primary efficacy variable at week 24 was the American College of Rheumatology (ACR) response rate using the intent-to-treat population.</p><p><b>RESULTS</b>The ACR response rate was significantly higher in the T-614 treatment group compared with the placebo group within 8 weeks after the initiation of treatment. After 24 weeks, the 25 mg/d and 50 mg/d dosage groups and the placebo group showed 39.13%, 61.29% and 24.21% in ACR20 and 23.91%, 31.18% and 7.37% in ACR50, respectively. A time-response in ACR response was observed, with clear superiority for the 25 mg/d and 50 mg/d dosage groups compared to placebo (P < 0.0001), and the 50 mg/d dose compared to the 25 mg/d dose (P < 0.05) when using the ACR response analyses after 24 weeks. ESR and c-reactive protein (CRP) were significantly different in the treatment groups after 24 weeks. The incidence of adverse events (AEs) was not significantly higher with T-614 than with placebo, but upper abdominal discomfort, leucopenia, elevated serum alanine aminotransferase (sALT), skin rash and/or pruritus were more common in the 50 mg and 25 mg dosage groups.</p><p><b>CONCLUSION</b>T-614, a new slow-acting drug, is effective in treatment of rheumatoid arthritis and is well tolerated.</p>