Targeting mast cells in endometriosis with janus kinase 3 inhibitor, JANEX-1

Endometriosis (EMS) is a chronic inflammatory disease of multifactorial etiology characterized by implantation and growth of endometrial glands and stroma outside the uterine cavity. EMS is a significant public health issue as it affects 15-20% of women in their reproductive age. Clinical symptoms may include pelvic pain, dysmenorrhea, dyspareunia, pelvic/abdominal masses, and infertility. Symptomatic treatments such as surgical resection and/or hormonal suppression of ovarian function and analgesics are not as effective as desired. Consequently, there is an enormous unmet need to develop effective medical therapy capable of preventing the occurrence and recurrence of EMS without undesirable side-effects. EMS-associated intra-abdominal bleeding episodes, local inflammation, adhesions, and i.p. immunologic dysfunction leads to pelvic nociception and pelvic pain. Increasing evidence supports the involvement of allergic-type inflammation in EMS. Invasion of mast cells, degranulation, and proliferation of interstitial component are observed in endometriotic lesions. Presence of activated and degranulating mast cells within the nerve structures can contribute to the development of pain and hyperalgesia by direct effects on primary nociceptive neurons. Therefore, treatments targeting endometrial mast cells may prove effective in preventing or alleviating EMS-associated symptoms. The Janus kinase 3 (JAK3) is abundantly expressed in mast cells and is required for the full expression of high-affinity IgE receptor-mediated mast cell inflammatory sequelae. JANEX-1/WHI-P131 is a rationally designed novel JAK3 inhibitor with potent anti-inflammatory activity in several cellular and in vivo animal models of inflammation, including mouse models of peritonitis, colitis, cellulitis, sunburn, and airway inflammation with favorable toxicity and pharmacokinetic profile. We hypothesize that JAK3 inhibitors, especially JANEX-1, may prove useful to prevent or alleviate the symptoms of EMS.     

Effective immunochemotherapy of CALLA+C mu+ human pre-B acute lymphoblastic leukemia in mice with severe combined immunodeficiency using B43 (anti-CD19) pokeweed antiviral protein immunotoxin plus cyclophosphamide.

A highly aggressive human CALLA+C mu+ pre-B acute lymphoblastic leukemia (ALL) cell line (NALM-6-UM1) causes disseminated and invariably fatal leukemia in CB.17 mice with severe combined immunodeficiency (SCID). We used this SCID mouse model of human pre-B ALL to evaluate and compare, in a total of 434 SCID mice, the antileukemic efficacy of B43 (anti-CD19)-pokeweed antiviral protein (PAP) immunotoxin and cyclophosphamide (CPA) as individual reagents and as combined immunochemotherapeutic regimens. B43-PAP plus CPA was superior to either the immunotoxin or drug alone, and combined immunochemotherapy markedly improved the event-free survival (EFS) of SCID mice challenged with NALM-6-UM1 pre-B ALL cells. Notably, 90% to 100% of SCID mice challenged with 1 x 10(6) leukemia cells and then treated with B43-PAP plus CPA combined immunochemotherapy regimens became long-term survivors, a result not achieved with B43-PAP alone or CPA alone. The advantage was particularly evident in mice inoculated with 5 x 10(6) leukemia cells. While neither 15 micrograms B43-PAP (median survival, 58 days) nor 1 mg CPA (median survival, 49 days) resulted in long-term EFS of SCID mice challenged with 5 x 10(6) NALM-6-UM1 pre-B ALL cells, the probability of EFS at 6 months was 50% +/- 16% for SCID mice treated with 15 micrograms B43-PAP plus 1 mg CPA (median survival, greater than 180 days) (P less than .0001). The probability of long-term EFS was only 14% +/- 7% for mice treated with 30 micrograms B43-PAP and 0% +/- 0% for mice treated with 1 mg CPA, but 40% +/- 16% for mice treated with 30 micrograms B43-PAP plus 1 mg CPA (P less than .0001). Similarly, the probability of EFS at 6 months was 40% +/- 16% for mice treated with 2 mg CPA alone, 70% +/- 15% for mice treated with 2 mg CPA plus 15 micrograms B43-PAP, and 70% +/- 15% for mice treated with 2 mg CPA plus 30 micrograms B43-PAP. Ten SCID mice in the B43-PAP plus CPA combined immunochemotherapy arms surviving long term after the inoculation of 5 x 10(6) NALM-6-UM1 pre-B ALL cells were electively killed at 174 to 181 days to assess their leukemia burden. We found no evidence of leukemia in any of the bone marrow specimens by two-color immunofluorescence and multiparameter flow cytometry.(ABSTRACT TRUNCATED AT 400 WORDS)     

Radiation and heat sensitivity of human T-lineage acute lymphoblastic leukemia (ALL) and acute myeloblastic leukemia (AML) clones displaying multiple drug resistance (MDR).

The hyperthermia as well as radiation responses of multidrug resistant (CEM/VLB100 with classical MDR and CEM/VM-1 with atypical MDR), methotrexate resistant (CEM/MTX) subclones of CCRF-CEM T-lineage ALL cell line were compared with those of a drug sensitive (CEM-1-3) subclone from the same parent cell line. Also analyzed were the hyperthermia as well as radiation responses of multidrug resistant (HL60/AR) and drug sensitive subclones of the HL60 AML cell line. Notably, the drug resistant subclones of CEM and HL60 were as sensitive to hyperthermia as were the drug sensitive subclones. Importantly, no thermotolerant plateau was observed in the hyperthermia survival curves of the drug resistant subclones, indicating that drug/multidrug resistance is not associated with a greater likelihood of thermal tolerance development during hyperthermia. Similarly, the drug resistant CEM and HL60 subclones were not more radiation resistant than the drug sensitive subclones. Thus, the classical or atypical forms of multidrug resistance or methotrexate resistance of the analyzed leukemic cell lines were not associated with radiation resistance. Furthermore, the radiation survival curves of the drug resistant subclones lacked a distinct initial shoulder and their n values were not greater than those of the drug sensitive subclones, suggesting that multidrug resistance is not associated with an increased ability to repair or accumulate sublethal radiation damage. Our findings provide evidence that there is no apparent association between drug/multidrug resistance and heat or radiation sensitivity of CEM T-lineage ALL or HL60 AML leukemia cells. The results of this study indicate that acquired resistance to methotrexate, vinblastine, vincristine, etoposide, actinomycin-D, adriamycin, or daunomycin, or pleiotropic multidrug resistance do not necessarily confer radiation resistance for human leukemic cells.     

Targeting JAK3 with JANEX-1 for prevention of autoimmune type 1 diabetes in NOD mice

Here we show that Janus kinase (JAK) 3 is an important molecular target for treatment of autoimmune insulin-dependent (type 1) diabetes mellitus. The rationally designed JAK3 inhibitor JANEX-1 exhibited potent immunomodulatory activity and delayed the onset of diabetes in the NOD mouse model of autoimmune type 1 diabetes. Whereas 60% of vehicle-treated control NOD mice became diabetic by 25 weeks, the incidence of diabetes at 25 weeks was only 9% for NOD females treated with daily injections of JANEX-1 (100 mg/kg/day) from Week 10 through Week 25 (P = 0.007). Furthermore, JANEX-1 prevented the development of insulitis and diabetes in NOD-scid/scid females after adoptive transfer of splenocytes from diabetic NOD females. Chemical inhibitors such as JANEX-1 may provide the basis for effective treatment modalities against human type 1 diabetes. To our knowledge, this is the first report of the immunosuppressive activity of a JAK3 inhibitor in the context of an autoimmune disease.     

Toxicity and pharmacokinetics of stampidine in mice and rats

The in vivo toxicity and pharmacokinetics of stampidine (CAS 217178-62-6), an aryl phosphate derivative of stavudine (CAS 3056-17-5) under development as a new anti-human immunodeficiency virus (anti-HIV) agent, were studied in mice and rats. Stampide was very well tolerated by both mice and rats without any toxicity at cumulative dose levels > 1 g/kg. Therapeutic micromolar plasma concentrations of stampidine and its active metabolites ala-STV-MP (CAS 180076-92-0) and STV were rapidly achieved and maintained several hours after i.p. administration of the nontoxic 25-50 mg/kg bolus doses of stampidine. The remarkable in vivo safety of stampidine warrants the further development of this promising new antiviral agent for possible clinical use in HIV-infected patients.     

Clinical activity of folinic acid in patients with chronic fatigue syndrome

A high incidence of severe B-cell immunodeficiency and chronic reactivated Epstein-Barr virus (EBV) infection in patients with chronic fatigue syndrome (CFS) is reported herein. Of the 58 patients evaluated, 100% had evidence of prior EBV exposure and 72% had evidence for reactivated EBV infection. Notably, 94% of CFS patients had B-cell immunodeficiency with a marked depletion of their CD19+IgM+ mature B-lymphocyte population. A remarkable 81% of CFS patients experienced subjective improvement of their symptoms after treatment with folinic acid (CAS 58-05-9, leucovorin). The findings provide unprecedented evidence that CFS frequently is a folinic acid responsive clinical entity accompanied by B-cell immunodeficiency and inappropriate antibody responses to EBV.     

Importance of the alanine methyl ester side chain for the biological activity profile of dual-function phenyl phosphate derivatives of bromo-methoxy-zidovudine

In a systematic search for developing a virucidal spermicide with potent anti-human immunodeficiency virus (HIV) and spermicidal activities, we synthesized and evaluated 14 phosphoramidate derivatives of 5-bromo-6-methoxy-zidovudine (PP-BMZ) with differing amino acid ester side chains and para substitutions on the phenyl moiety. Anti-HIV activity was tested by measuring viral p24 antigen production as a marker of viral replication in HIV-1-infected human peripheral blood mononuclear cells. The effect of various PP-BMZ compounds on human sperm motion kinematics was analysed by computer-assisted sperm analysis. Varying the Ala side chain of the phosphoramidate group to other non-polar amino acids, including the cyclic amino acids proline and tryptophan, led to significant alterations in both anti-HIV and spermicidal activities. Our findings highlight the necessity of the Ala side chain and the presence of an electron-withdrawing para-bromo substituent on the phenyl moiety in addition to the bromo-methoxy functional groups on the thymine ring for the PP-BMZ compounds to be effective virucidal spermicides. These membrane permeable dual-function nucleoside analogues may provide the basis for a new strategy aimed at prevention of the sexual transmission of HIV while providing fertility control for women.     

Treatment of post-bone marrow transplant acute graft-versus-host disease with a rationally designed JAK3 inhibitor

Here we show that the Janus kinase 3 (JAK3) inhibitor 4-(3'-hydroxyphenyl)-amino-6,7-dimethoxyquinazoline (JANEX-3) exhibits potent anti-GVHD activity and consequently improves the post-BMT survival outcome of C57BL/6 (H-2b) recipient mice transplanted with allogeneic bone marrow/splenocyte (BM/S) grafts from MHC disparate BALB/c mice (H-2d). One hundred percent of the vehicle-treated allograft recipients developed severe GVHD and died with a median survival of 41 days. Treatment of recipient mice with JANEX-3 (30 mg/kg/day, 3 x/day) after the onset of rapidly progressive severe GVHD in the 3rd week after BMT significantly improved the survival of BMT recipients with GVHD and prolonged the median survival time to 78 days (P < 0.0001, log-rank test). The probability of survival at two and three months post-BMT was 6 +/- 6% and 0 +/- 0% for vehicle-treated control mice and 100 +/- 0% and 38 +/- 17% for mice treated with JANEX-3. These results prompted the hypothesis that JAK3 plays a pivotal role in the pathophysiology of GVHD. To test this hypothesis, we examined if mice transplanted with allogeneic BM/S grafts from Jak3 knockout mice Jak3-/- develop GVHD. The allografts from (Jak3-/-) C57BL/6 (H-2b) mice rescued MHC-disparate recipient BALB/c mice (H-2d) of the lethal toxicity of TBI without causing fatal GVHD. Taken together, these observations establish JAK3 as a key mediator of severe GVHD after allogeneic BMT in the context of a major-HLA disparity.     

Spongistatins as tubulin targeting agents

Recently identified novel agents that disrupt tubulin polymerization include synthetic spiroketal pyrans (SPIKET) targeting the spongistatin binding site of b-tubulin. These agents exhibit anticancer activity by disrupting normal mitotic spindle assembly and cell division as well as inducing apoptosis. At nanomolar concentrations, the SPIKET compound SPIKET-P caused tubulin depolymerization in cell-free turbidity assays and exhibited potent cytotoxic activity against cancer cells as evidenced by destruction of microtubule organization, and prevention of mitotic spindle formation in human breast cancer cells. SPIKET compounds represent a new class of tubulin targeting agents that show promise as anti-cancer drugs.     

Pokeweed antiviral protein: a potential nonspermicidal prophylactic antiviral agent

OBJECTIVE: To investigate the effects of pokeweed antiviral protein (PAP), a 29-kDa anti-human immunodeficiency virus (HIV) protein purified from the leaves of Phytolacca americana, on human sperm function. DESIGN: Prospective, controlled study. SETTING: Reproductive biology department. PATIENT(S): Seven sperm donors. INTERVENTION(S): Human sperm and female genital tract epithelial cells were exposed to PAP ranging in concentration from 1 to 1,000 microg/mL. MAIN OUTCOME MEASURES: Effect of PAP on sperm motility, kinematics, and sperm penetration through bovine mucus, as well as binding, penetration, and fusion of zona-free hamster eggs. RESULTS: Exposing human sperm to PAP (IC(50) p24 = 14 +/- 2 nM) did not affect sperm motility and kinematics over a dose range of 1 to 1,000 microg/mL. Treating sperm with either 100 or 1,000 microg/mL of PAP had no effect on cervical mucus penetrability, nor did it affect sperm binding, penetration, and fusion of zona-free hamster eggs. PAP was noncytotoxic to genital-tract epithelial cells. CONCLUSIONS: The broad-spectrum antiviral agent PAP was nontoxic to human sperm and female genital tract epithelial cells even at a concentration 2,000 times higher than its IC(50) value against HIV-1. PAP has particular clinical usefulness both as a nonspermicidal intravaginal microbicide and as a prophylactic antiviral agent that can inactivate infective viruses and virus-infected cells in semen before assisted reproductive technology procedures are undertaken.