Synthesis and anti-trypanosomal activity of 3'-fluororibonucleosides derived from 7-deazapurine nucleosides.

Trypanosoma brucei parasites cause Human African Trypanosomiasis and the current drugs for its treatment are often inefficient and toxic. This urges the need to development of new antitrypanosomal agents. We report the synthesis and biological profiling of 3'-deoxy-3'-fluororibonucleosides derived from 7-deazaadenine nucleosides bearing diverse substituents at position 7. They were synthesized through glycosylation of 6-chloro-7-bromo- or -7-iodo-7-deazapurine with protected 3'-fluororibose followed by cross-coupling reactions at position 7 and/or deprotection. Most of the title nucleosides displayed micromolar or submicromolar activity against Trypanosoma brucei brucei. The most active were the 7-bromo- and 7-iododerivatives which exerted double-digit nanomolar activity against T. b. brucei and T. b. gambiense and no cytotoxicity and thus represent promising candidates for further development.

MAIT cells as attractive vaccine targets.

Mucosal-associated invariant T (MAIT) cells are a subset of T cells that perform innate-like immunity functions upon recognition of small molecule vitamin B metabolites presented by the MHC, class I-related protein-1 (MR1). MAIT cells are profuse in humans, but especially abundant in blood, liver, lungs, and mucosal layers. The mucosa is a common site of carcinogenesis and MAIT cells have been found in both primary and metastatic tumors. MAIT cells target a host of microbes including Mycobacterium tuberculosis, Staphylococcus aureus, Salmonella enterica, Legionella longbeachae, Escherichia coli, and Candida albicans, and are highly activated in viral infections. Cytokines produced by MAIT cells are both anticancerous and antibacterial, but also have proinflammatory and possibly tumorigenic properties. In addition, it is believed that MAIT cells play a protective role in viral infections in an MR1-independent fashion. Based on our summary of recent advances concerning both MR1-mediated and MR1-independent MAIT cell immune responses, we weigh the strengths and weaknesses of these cells for vaccine development.

Synthesis of Nucleosides through Direct Glycosylation of Nucleobases with 5-O-Monoprotected or 5-Modified Ribose: Improved Protocol, Scope, and Mechanism.

Simplifying access to synthetic nucleosides is of interest due to their widespread use as biochemical or anticancer and antiviral agents. Herein, a direct stereoselective method to access an expansive range of both natural and synthetic nucleosides up to a gram scale, through direct glycosylation of nucleobases with 5-O-tritylribose and other C5-modified ribose derivatives, is discussed in detail. The reaction proceeds through nucleophilic epoxide ring opening of an in situ formed 1,2-anhydrosugar (termed "anhydrose") under modified Mitsunobu reaction conditions. The scope of the reaction in the synthesis of diverse nucleosides and other 1-substituted riboside derivatives is described. In addition, a mechanistic insight into the formation of this key glycosyl donor intermediate is provided.

Intravesical chondroitin sulphate for interstitial cystitis/painful bladder syndrome.

INTRODUCTION: Interstitial cystitis/painful bladder syndrome (IC/PBS) is a chronic inflammatory condition of the bladder. Bladder instillation is one avenue of treatment but evidence for its effectiveness is limited. Chondroitin sulphate solution 2.0% (Urocyst) is a glycosaminoglycan (GAG) replenishment therapy instilled for patients with IC/PBS. We assessed its effectiveness for treating IC/PBS in Northern Ireland. METHODS: Patients with IC/PBS were assessed with the O'Leary-Sant interstitial cystitis index score and global response assessment questionnaire prior to commencing treatment. Assessment with these questionnaires was performed after 6 treatments (10 weeks) and again after 10 treatments (24 weeks). Assessment end points were pain, urgency, symptom score and problem score. RESULTS: Data was collected on 10 patients, 9 female and 1 male. 6 patients had failed RIMSO-50 dimethyl sulphoxide (DMSO) 50% treatment prior. At baseline the mean pain score was 6.6, urgency score 7.00, symptom score 13.5 and problem score 12.5. After 24 weeks the mean pain score fell to 2.0, urgency score to 1.80, symptom score to 6.89 and problem score to 5.67. At 10 weeks the global response to treatment was 100%. Nocturia was the first symptom to improve with urgency and pain following. No side effects were noted during instillation and all patients tolerated the treatments. CONCLUSION: IC/PBS is a difficult disease to treat. It requires a multimodal approach. We found that intravesical chondroitin sulphate reduced pain, urgency and O'Leary-Sant symptom and problem scores in patients with IC/PBS. All patients tolerated the treatment and no side effects were reported.

Co-existence of breast and ovarian cancers in BRCA germ-line mutation carriers.

The co-existence of breast and ovarian cancers in the same individual should raise suspicion of a hereditary process. Patients with either BRCA1 or BRCA2 germ-line mutations have an average risk of 39% and 11% respectively of developing ovarian cancer by the age of 70; they have a risk of 35-85% of developing breast cancer in their lifetime. We report here unusual pathologic features in a BRCA2 germ-line mutation carrier recently diagnosed with synchronous breast and ovarian cancers, and summarize the findings in six other women who were diagnosed with ovarian cancer either simultaneously with the diagnosis of breast cancer or at varying times after the diagnosis. While in most instances this may be a coincidental occurrence in highly susceptible individuals, the patient we highlight raises the provocative hypothesis that at times breast cancer metastasizes to the ovaries of mutation carriers and stimulates the development of an ovarian cancer as well as other cancers. In addition, these ovarian cancers may have different mechanisms of metastases predisposing them to travel to unusual sites.

Pegylated liposomal doxorubicin (PLD): enhanced skin toxicity in areas of vitiligo.

Pegylated liposomal doxorubicin (PLD, Doxil, Caelyx) is widely used for the treatment of ovarian cancer. It is a stable formulation encapsulating doxorubicin in a 'Stealth' (i.e., pegylated) liposome with a half-life of about 72 hours. This drastically altered pharmacology confers on it a considerably lower risk of cardiotoxicity, no acute emesis, and near absence of alopecia or problems with extravasation necrosis. On the other hand, PLD's dose-limiting toxicity is cutaneous. Since the original phase I report, cutaneous toxicities reported with PLD fall into four common categories: the well known hand-foot syndrome (also called palmoplantar erythrodysesthesia, or PPE), a diffuse follicular rash, intertrigo-like eruption, and hyperpigmentation including melanotic macules.

Pegylated liposomal doxorubicin HCL (PLD; Caelyx/Doxil): experience with long-term maintenance in responding patients with recurrent epithelial ovarian cancer.

BACKGROUND: We hypothesized that a response to pegylated liposomal doxorubicin (PLD, Caelyx/Doxil) followed by maintenance is beneficial and safe in recurrent ovarian cancer. PATIENTS AND METHODS: Sixteen patients have received PLD for more than 1 year for recurrent ovarian (14) or fallopian tube (2) cancer. All had stable disease or better responses to PLD + carboplatin (5) or topotecan (9) doublets or to PLD alone (2). PLD maintenance therapy 30-40 mg/m(2) was given every 4-8 weeks. This analysis focuses on cardiac status, overall tolerance, and time to recurrence. RESULTS: Termination of PLD was due to progression in all patients. Noteworthy was the lack of cumulative myelosuppression and, with one exception, clinical cardiac toxicity. This patient was hospitalized with cardiogenic shock and fever complicating grade 4 pancytopenia from topotecan ten months after discontinuation of PLD. Seven patients continue to receive PLD after a median of 1680 mg/m(2) (1180-2460 mg/m(2)). Four of these had documented relapses after 3-6 years on maintenance occurring in the setting of lengthening of the treatment interval. Maintenance PLD was reinstituted after 'reinduction' with a platinum. CONCLUSIONS: PLD appears to be safe as long-term maintenance in ovarian cancer and may be important for a continued response.

Intraperitoneal topoisomerase-I inhibitors. Preliminary findings with 9-aminocamptothecin.

The i.p. administration of topoisomerase I (Topo I) inhibitors has a pharmacologic advantage over intravenous application, including preservation of the biologically active lactone form. In our ongoing study, patients have received 9-amino-20(S)-camptothecin (9-AC) i.p. on days 1, 3, 5, 8, 10, and 12, repeated every 4 weeks. The daily dose has been escalated to level IV of 1.5 mg/m2 (9.0 mg/m2 per course), median of 3 cycles, range 1-4, with a reversible Grade 3 neutropenia in one patient. Responses included one CR (resolution of a pleural effusion), two patients without progressive disease (PD), two not evaluable, and two patients too early for evaluation. The area under the curve (AUC)i.p./AUCpl ratio (pharmacologic advantage) ranged from 7.6 to 16.5 on average, and, using nonlinear modeling, the pharmacologic decay data were fit to one- or two-compartmental models. Overall, a 9-AC i.p. application is well tolerated and anticipated to be an active regimen against i.p. malignancies, particularly those known to be sensitive to systemic Topo-I inhibitors.

Phase II trial of paclitaxel and cisplatin in women with advanced breast cancer: an active regimen with limiting neurotoxicity.

PURPOSE: A phase II study of paclitaxel and cisplatin in patients with advanced breast cancer was performed to determine the objective response rate and make further observations about the toxicity of this regimen. PATIENTS AND METHODS: Patients were required to have histologically proven adenocarcinoma of the breast with no more than one chemotherapeutic treatment for advanced disease. Treatment consisted of paclitaxel 200 mg/m2 administered as a 24-hour intravenous (i.v.) infusion followed by cisplatin 75 mg/m2 i.v. Patients received granulocyte colony-stimulating factor (G-CSF) 5 micrograms/kg subcutaneously on day 3 until WBC recovery. Cycles were repeated every 21 days. Patients continued to receive therapy until disease progression or unacceptable toxicity. RESULTS: Forty-four patients entered the trial. Forty-two patients were assessable for response. Nineteen patients (43%) had no prior chemotherapy and 41 had no chemotherapy for metastatic disease. The median number of cycles administered per patient was five (range, one to seven). There were five complete responses (CRs) (11.9%) and 17 partial responses (PRs) (40.5%), with an overall response rate of 52.4% (95% confidence interval [CI], 36.4% to 68.0%). Nine patients had stage III disease. The response rate for this group was 66.7% (95% CI, 33.0% to 92.5%), with three CRs and three PRs. Among 35 patients with stage IV disease, there were two CRs and 14 PRs, with an overall response rate of 48.5% (95% CI, 30.8% to 66.5%). Overall, the median response duration was 10.6 months. Thirty patients (68%) developed transient grade 4 neutropenia. Cumulative neuropathy was the major dose-limiting toxicity. After five cycles of chemotherapy, 96% of patients had at least grade 1 neurotoxicity and 52% had at least grade 2 neurotoxicity. One patient had a toxic death after cycle 1 of therapy. CONCLUSION: The combination of paclitaxel and cisplatin as first-line chemotherapy for women with advanced breast cancer is an active regimen. However, the cumulative neurotoxicity was significant and dose-limiting in the majority of patients.

Phase I study of doxorubicin, ICRF-187 and granulocyte/macrophage-colony-stimulating factor.

A group of 16 patients with advanced malignancy were entered on a phase I trial of escalating doses of doxorubicin with ICRF-187 for cardioprotection and granulocyte/macrophage-colony-stimulating factor (GMCSF) for bone marrow protection. Patients received intravenous ICRF-187 (dose ratio 20:1 ICRF-187:doxorubicin) 30 min prior to doxorubicin. GMCSF at a dose of 15 micrograms kg-1 day-1 was self-administered subcutaneously on days 3-14 of the cycle. Doxorubicin was administered every 21 days. Substantial hematological and non-hematological toxicity was seen. Fever, malaise, and pulmonary symptoms, thought to be due to GMCSF, were not eliminated by reduction in the GMCSF dose to 10 or 5 micrograms kg-1 day-1. Severe hematological toxicity was seen despite GMCSF administration and it was not possible to escalate the doxorubicin dose above 72 mg/m2 with this combination. Dose escalation of doxorubicin may be more feasible with the use of other growth factors or growth factor combinations.

Prevention of atherosclerosis in childhood.

Atherosclerosis begins in infancy, with fatty streaks appearing at the age of 3 years and fibrous plaques appearing during adolescence. Fatty streaks and fibrous plaques are related to serum total cholesterol, LDL-C, and systolic blood pressure levels. Children with elevated levels of cholesterol and blood pressure track (i.e., maintain elevated levels over time) and are candidates for premature coronary artery and cerebrovascular disease, especially if there is a positive family history of premature CVD. Screening for CVD risk factors in children is rapid, simple, inexpensive, and effective, with tremendous potential to prevent future adult CVD. At their annual physical examinations, children 5 years of age or older should have careful blood pressure measurements by two observers, and determinations of serum total cholesterol levels. Levels should be plotted on standard percentile grids (Figs. 5-7) in the child's permanent medical record. Those with persistently elevated levels of blood pressure and/or serum LDL-C require nonpharmacologic intervention initially, but may require antihypertensive or antilipid medication if unresponsive to behavioral modification for diet, physical activity, and cigarette smoking. Pediatric health professionals can play vital roles in primary prevention and reduction of adult CVD.

PUVA therapy of chronic actinic dermatitis.

Four men with long-standing chronic actinic dermatitis were treated with a modified PUVA regime which initially included generalized applications of topical steroids given immediately after PUVA exposure. All patients are now free of rash, no longer need protection from UV radiation, and are being maintained on twice monthly PUVA therapy (IO J/cm2).

Dithranol-UV-A phototherapy (DUVA) for psoriasis: a treatment without dressings.

Dithranol in yellow soft paraffin with 2% salicylic acid was applied daily (increasing concentrations from 0.2% to 5%) for 1 hour to twenty consecutive patients with diffuse psoriasis. The ointment was then washed off and patients were irradiated with 10 J cm-2 of UV-A radiation since the absorption spectrum of dithranol is maximum in the UV-A waveband. The median clearance time was 14 days (range 7-39 days). No dressings were required. The patients were allowed to apply an emollient if the skin became dry.