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Introduction: Bladder cancer care has been increasingly concentrated in high-volume metropolitan medical centres (ie, "regionalisation" of care). We aimed to assess the potential role of geographic factors, including facility region and distance to treatment centre, as determinants of neoadjuvant chemotherapy (NAC) delivery in patients with non-metastatic urothelial muscle-invasive bladder cancer (MIBC) using nationally representative data from the United States., Methods: We queried the National Cancer Database to identify patients with cT2-cT4a, N0M0 urothelial MIBC who underwent radical cystectomy (RC) from 2006 to 2015. Patients who received radiation therapy, single-agent chemotherapy, adjuvant chemotherapy or systemic therapies other than multi-agent chemotherapy were excluded. Multivariate logistic regression analysis was performed to identify independent predictors of receiving NAC., Results: A total of 5986 patients met the criteria for inclusion, of whom 1788 (29.9%) received NAC and 4108 received RC alone. Younger age, increased Charlson-Deyo score, increased cT stage, increased annual income, increased distance from cancer treatment centre, treatment at an Academic Research Program or Integrated Network Cancer Program and a later year of diagnosis were independently predictive of NAC receipt. Older age, Medicare insurance and treatment in the East South Central or West South Central regions were independently associated with decreased odds of NAC receipt., Conclusions: Distance to treatment centre and United States geographic region were found to affect the likelihood of NAC receipt independently of other established predictors of success in this quality-of-care metric. Access to transportation and related resources merits consideration as additional pertinent social determinants of health in bladder cancer care., (© 2021 John Wiley & Sons Ltd.)

Aims: To assess the efficacy of traditional first-line non-antidiuretic pharmacotherapy for nocturia in the real-world outpatient urology setting., Methods: We retrospectively analyzed voiding diaries from adult men treated for lower urinary tract symptoms (LUTS) at an outpatient urology clinic to identify pairs of voiding diaries with ≥1 nocturnal void at baseline and a corresponding follow-up diary completed within 1 year. We compared the odds of nocturia improvement (decrease of ≥1 nocturnal void) in patients started on LUTS pharmacotherapy versus behavioral modification alone., Results: Two hundred and thirteen diary pairs from 93 patients were included. Fifty-seven diary pairs were identified from patients prescribed at least one LUTS drug on the initial visit and 156 diary pairs were identified from patients receiving behavioral modification alone. All standard voiding diary parameters were assessed, and only maximum voided volume differed at baseline (240 ml [interquartile range: 200-330 ml] vs. 280 ml [200-400 ml] with and without pharmacotherapy, respectively, p = 0.04). The odds of nocturia improvement did not significantly differ between pharmacotherapy and behavioral modification treatment groups (crude odds ratio [OR]: 1.16 [95% confidence interval: 0.63-2.16], p = 0.63; maximum voided volume [MVV]-adjusted OR: 1.19 [0.63-2.22], p = 0.59). In contrast, improvement in 24-h urinary frequency was more likely with pharmacotherapy versus behavioral modification alone (crude OR: 2.36 [1.22-4.56], p = 0.01; MVV-adjusted OR: 2.05 [1.05-4.01], p = 0.04). Results were consistent on subgroup analyses restricted to first diary pairs from each patient., Conclusion: Despite improvement in 24-h voiding frequency, there was no evidence that adjunctive pharmacotherapy provided a benefit in the treatment of nocturia in men receiving behavioral counseling., (© 2021 Wiley Periodicals LLC.)

Purpose: Recent literature has separately identified multiple determinants of the use of neoadjuvant chemotherapy (NAC) and adherence to pelvic lymph node dissection (PLND) guidelines in the management of non-metastatic bladder cancer. However, such NAC/PLND analyses tend not to account for the other modality, despite the fact that NAC may impact the extent of dissectible lymph nodes. We aimed to determine the predictors of adequate PLND in patients with non-metastatic urothelial muscle-invasive bladder cancer (MIBC) undergoing radical cystectomy (RC) following receipt of NAC., Methods: We queried the National Cancer Database to identify patients from 2006-2015 with cT2-cT4a/N0M0 urothelial MIBC who underwent RC and were pre-treated with NAC. Multivariate logistic regression analysis was used to identify independent predictors of undergoing an adequate PLND (defined as > 8 nodes)., Results: A total of 1518 patients met the criteria for inclusion (74.4% underwent adequate PLND). Adequate PLND was associated with treatment at an academic research facility (OR 2.762 [95% CI 2.119-3.599], p < 0.001). The likelihood of adequate PLND was significantly decreased in patients of older age (0.607 [0.441-0.835], p = 0.002 for age 70-79 years; 0.459 [0.245-0.860], p = 0.015 for age ≥ 80 years), a Charlson-Deyo score of 1 (0.722 [0.537-0.971], p = 0.031), and those who were uninsured (0.530 [0.292-0.964], p = 0.038)., Conclusions: Established predictors of PLND may not necessarily be generalizable to all patients undergoing treatment for bladder cancer. The interplay between PLND and NAC merits further study, particularly in view of recent literature calling into question the survival benefit of PLND in patients pre-treated with NAC.

Background: Primary small cell carcinoma of the kidney (PSCCK) is exceedingly rare and data on disease characteristics and outcomes are sparse. This study examines a nationally-representative cancer registry to better characterize PSCCK. Methods: We queried the National Cancer Database to identify patients with histology-confirmed PSCCK from 2004 to 2015. Adjusted Cox proportional hazards regression and Kaplan-Meier analyses were employed to assess predictors of mortality and estimate median survival time, respectively. Results: A total of 110 patients were included (47:53% female:male, 77% ≥60 years of age, 86% Caucasian). Significant predictors of mortality included female sex, age 60-69 years, treatment at an Integrated Network Cancer Program, stage cM1, and lack of surgical and chemoradiotherapy treatment. Independent protective factors were high socioeconomic status and treatment at an Academic Research Program. The estimated median overall survival time was 9.31 (95% CI 7.28-10.98) months for all patients. No differences in estimated survival time were observed across individual treatment modalities among those patients who underwent treatment ( p = 0.214). Conclusions: PSCCK is an aggressive malignancy with a median survival time of less than one year. Future studies that correlate clinical tumor staging with specific treatment modalities are needed to optimize and individualize management.

Background: The rapid spread of COVID-19 has placed tremendous strain on the American healthcare system. Few prior studies have evaluated the well-being of or changes to training for American resident physicians during the COVID-19 pandemic. We aim to study predictors of trainee well-being and changes to clinical practice using an anonymous survey of American urology residents., Methods: An anonymous, voluntary, 47-question survey was sent to all ACGME-accredited urology programmes in the United States. We executed a cross-sectional analysis evaluating risk factors of perception of anxiety and depression both at work and home and educational outcomes. Multiple linear regressions models were used to estimate beta coefficients and 95% confidence intervals., Results: Among ~1800 urology residents in the USA, 356 (20%) responded. Among these respondents, 24 had missing data leaving a sample size of 332. Important risk factors of mental health outcomes included perception of access to PPE, local COVID-19 severity and perception of susceptible household members. Risk factors for declination of redeployment included current redeployment, having children and concerns regarding ability to reach case minimums. Risk factors for concern of achieving operative autonomy included cancellation of elective cases and higher level of training., Conclusions: Several potential actions, which could be taken by urology residency programme directors and hospital administration, may optimise urology resident well-being, morale, and education. These include advocating for adequate access to PPE, providing support at both the residency programme and institutional levels, instituting telehealth education programmes, and fostering a sense of shared responsibility of COVID-19 patients., (© 2020 John Wiley & Sons Ltd.)

Study Objectives: The goal of this study was to compare the urge perception associated with nocturnal voiding at the time of voiding in individuals with and without depression, posttraumatic stress disorder (PTSD), or anxiety diagnoses to test the hypothesis that patients with such diagnoses are more likely to experience insomnia-driven convenience voiding during the sleep period., Methods: A database of voiding diaries with urge perception grades (UPGs) from 429 adult males seeking treatment for nocturia at a Veterans Affairs-based urology clinic was analyzed. The UPG categorizes perception for urinating from 0 (out of convenience) to 4 (desperate urge). Diaries completed by males age 18 years and older showing ≥ 2 nocturnal voids were included. Those included (n = 178) were divided into two cohorts based on the presence (n = 62) or absence (n = 116) of one or more previously established mental health diagnoses (depression, PTSD, or anxiety). The chi-square test was used to determine significance between groups., Results: Patients with a mental health diagnosis were more likely to report convenience voiding compared to those without depression, PTSD, or anxiety (14.5% versus 0.8%, P < .01). However, most voids in both groups were associated with the perception of urinary urgency. There were no differences in urinary volumes or hourly rates of urine production between the groups., Conclusions: A relatively small subset of urology patients experience nocturnal voiding because they are awake for reasons other than the urge to void. Mental health factors had a substantial, albeit minimal, effect. Most nocturia reflects urgency to urinate rather than voiding by convenience., (© 2019 American Academy of Sleep Medicine.)

Objectives: The most common complications after renal transplant are urologic and are a cause of significant morbidity in a vulnerable population. We sought to characterize the timing and predictors of urologic complications after renal transplant using a statewide database., Materials and Methods: We queried the New York Statewide Planning and Research Cooperative System database to identify patients who underwent renal transplant from 2005 to 2013. Postoperative complications included hydronephrosis, ureteral stricture, vesicoureteral reflux, nephrolithiasis, and urinary tract infections. Cox proportional hazards model was used to assess independent predictors of urologic complications., Results: In total, 9038 patients were included in the analyses. Urologic complications occurred in 11.3% of patients and included hydronephrosis (12.0%), nephrolithiasis (2.8%), ureteral stricture (2.4%), and vesicoureteral reflux (1.5%). We found that 23% experienced at least one urinary tract infection. On multivariate analysis, predictors of urologic complications included medicare insurance, hypertension, and prior urinary tract infection. Graft recipients from living donors were less likely to experience urologic complications than deceased-donor kidney recipients (P < .001)., Conclusions: Urologic complications occur in a significant proportion of renal transplants. Further study is needed to identify risk factors for complications after renal transplantation to decrease morbidity in this vulnerable population.

Purpose: We report the outcomes in patients with muscle invasive bladder cancer from 2 institutions who experienced a clinically complete response to neoadjuvant platinum based chemotherapy and elected active surveillance. It was unknown whether conservative treatment could be safely implemented in these patients., Materials and Methods: We retrospectively reviewed the records of patients with muscle invasive bladder cancer at our institutions who elected surveillance following a clinically complete response to transurethral resection of bladder tumors and neoadjuvant chemotherapy from 2001 to 2017. A clinically complete response was defined as absent tumor on post-chemotherapy transurethral resection of bladder tumor, negative cytology and normal cross-sectional imaging., Results: In the 148 patients followed a median of 55 months (range 5 to 145) the 5-year disease specific, overall, cystectomy-free and recurrence-free survival rates were 90%, 86%, 76% and 64%, respectively. Of the patients 71 (48%) experienced recurrence in the bladder, including 16 (11%) with muscle invasive disease and 55 (37%) with noninvasive disease. Salvage radical cystectomy prevented cancer specific death in 9 of 12 patients (75%) who underwent cystectomy after muscle invasive relapse and in 13 of 14 (93%) after noninvasive relapse., Conclusions: We observed high rates of overall and disease specific survival with bladder preservation in patients who achieved a clinically complete response to neoadjuvant chemotherapy. These outcomes support the safety of active surveillance in carefully selected, closely monitored patients with muscle invasive bladder cancer. Future studies should aim to improve patient selection by identifying biomarkers predicting invasive relapse and developing novel imaging methods of early detection., (Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Bladder-sparing treatment of muscle invasive bladder cancer (MIBC) with systemic chemotherapy plus transurethral resection of bladder tumors (TURBT) is increasingly seen in the literature -both in case series and subanalyses of patients who opt out of or are unfit for radical cystectomy (RC). Survival outcomes among these patients are often impressive, but these are typically small retrospective studies from single institutions and therefore of limited clinical value., Objectives: Our aim is to summarize the literature regarding definitive treatment of MIBC with systemic chemotherapy plus TURBT and provide a meta-analysis of survival outcomes for patients who received this treatment., Methods: A systematic literature search was performed consistent with the Prisma statement to identify publications reporting the outcomes of patients treated with TURBT and systemic chemotherapy as definitive treatment for locally confined MIBC. Identified studies were screened in a two-stage process: first by title and abstract; then by full-text reading. 18 publications (518 patients) were included in the qualitative systematic review and 10 publications (266 patients) were included in the meta-analysis. The primary objective was overall survival (OS)., Results: Overall survival ranged from 20% to 87.5% across studies at median follow-up ranging 4 to 120 months. 5-year survival rate for all patients included in the meta-analysis was estimated to be 72% [95% CI: 64%, 82%]., Conclusions: Definitive treatment with systemic chemotherapy plus TURBT can lead to favorable survival outcomes in select patients. Further study to improve patient selection for this method of treatment is needed.

Objective: To use a large population-level database to assess survival outcomes for collecting duct renal cell carcinoma (CDRCC)., Materials and Methods: The National Cancer Database was queried for all cases of CDRCC and clear cell renal cell carcinoma (CCRCC) from 2004 to 2013. After removing patients with other cancer diagnoses, the analytic cohort was composed of 201,686 CCRCC and 577 CDRCC cases. Kaplan-Meier and cox proportional hazards analysis were employed to model survival., Results: Compared to CCRCC, patients with CDRCC presented with higher grade and stage, node positive, and metastatic disease (70.7% vs. 30.0% with metastasis; P<0.001). Overall median survival for CDRCC was 13.2 months (95% CI: 11.0-15.5) compared to the 122.5 months (95% CI: 121.0-123.9) for CCRCC. On multivariate analysis of the CDRCC cohort, increasing T stage, high-grade disease, and metastasis were predictors of mortality. Of 184 patients with metastatic CDRCC, 113 underwent cytoreductive nephrectomy (CNx) whereas the rest were treated with chemo/radiation or observed. Survival outcomes were improved in patients who received both CNx with chemo/radiation compared to CNx alone (hazard ratio = 0.51, 95% CI: 0.32-0.79) or chemo/radiation alone (hazard ratio = 0.57, 95% CI: 0.37-0.89) on multivariate analysis., Conclusion: CDRCC is an aggressive subtype of renal cell carcinoma. Median survival is 13 months after diagnosis, drastically lower than for CCRCC. More than 70% of patients have metastatic disease at diagnosis. Chemo/radiation in addition to CNx is associated with a survival benefit over single mode therapy., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: The Phoenix definition (PD) and Stuttgart definition (SD) designed to determine biochemical recurrence (BCR) in patients with postradiotherapy and high-intensity focused ultrasound organ-confined prostate cancer are being applied to follow patients after cryosurgery. We sought to identify predictors of BCR using the PD and SD criteria in patients who underwent primary focal cryosurgery (PFC)., Materials and Methods: We performed a retrospective review of patients who underwent PFC (hemiablation) at 2 referral centers from 2000 to 2014. Patients were followed up with serial prostate-specific antigen (PSA). PSA levels, pre- and post-PFC biopsy, Gleason scores, number of positive cores, and BCR (PD = [PSA nadir+2ng/ml]; SD = [PSA nadir+1.2ng/ml]) were recorded. Patients who experienced BCR were biopsied, monitored carefully or treated at the discretion of the treating urologist. Cox regression and survival analyses were performed to assess time to BCR using PD and SD., Results: A total of 163 patients were included with a median follow-up of 36.6 (interquartile range: 18.9-56.4) months. In all, 64 (39.5%) and 98 (60.5%) experienced BCR based on PD and SD, respectively. On multivariable Cox regression, the number of positive pre-PFC biopsy cores was an independent predictor of both PD (hazard ratio [HR] = 1.4, P = 0.001) and SD (HR = 1.3, P = 0.006) BCRs. Post-PFC PSA nadir was an independent predictor of BCR using the PD (HR = 2.2, P = 0.024) but not SD (HR = 1.4, P = 0.181). Survival analysis demonstrated a 3-year BCR-free survival rate of 56% and 36% for PD and SD, respectively. Of those biopsied after BCR, 14/26 (53.8%) using the PD and 18/35 (51.4%) using the SD were found to have residual/recurrent cancer. Of those with prostate cancer on post-PFC biopsy, 57.1% of those with BCR by the PD and 66.7% of those with BCR by the SD were found to have a Gleason score ≥7., Conclusion: Both the PD and the SD may be used to determine BCR in post-PFC patients. However, the ideal definition of BCR after PFC remains to be elucidated., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: To report long-term follow-up results of a phase II trial of salvage intravesical nanoparticle albumin-bound (nab)-paclitaxel for patients with recurrent non-muscle-invasive bladder cancer after previous intravesical bacillus Calmette-Guérin (BCG) therapy., Methods: This was a phase II trial investigating the use of intravesical nab-paclitaxel in patients with recurrent Tis, Ta, and T1 urothelial carcinoma who failed at least 1 prior induction course of intravesical BCG. Patients received 500 mg/100 mL of nab-paclitaxel in 6 weekly intravesical instillations. Complete responders were offered full-dose maintenance for 6 months. Overall survival, recurrence-free survival, cystectomy-free survival, and cancer-specific survival were assessed via Kaplan-Meier analysis., Results: A total of 28 patients were enrolled with a median follow-up of 41 months (range 5-76). There were 22 men and 6 women with a median age of 79 (range 36-93), and the median number of prior intravesical therapies was 2. Twenty-one of the 28 patients (75%) were BCG refractory. Ten of the 28 patients (36%) achieved complete response. Six of the 28 patients remain cancer free, with a recurrence-free survival rate of 18%. Five-year overall and cancer-specific survival rates were 56% and 91%, respectively. Radical cystectomy occurred in 11 of the 28 patients (39%), of whom 2 out of 11 (18%) had pT2 or greater disease., Conclusion: With a median follow-up of 41 months, 18% of this cohort treated with nab-paclitaxel was disease free. Cystectomy-free survival was 61% and bladder cancer-specific mortality was 9%. Nab-paclitaxel is a reasonable treatment option in this high-risk population., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Efficient synthetic routes have been developed for the preparation of two new polyazamacrocycles tagged with structural motifs recognised by the Trypanosoma brucei P2 aminopurine transporter. Biological testing of these compounds showed highly selective anti-protozoal activity against trypanosomes.

A focused library of C2-substituted-1,4,7,10-tetraazacyclododecanes was synthesised and the compounds were tested for their ability to kill trypanosome and malaria parasites. Several compounds showed significant in vitro activity and were selectively active against the parasites over human embryonic kidney cells used as a counter screen.

A short, highly efficient approach for the synthesis of a novel class of polyazamacrocycles containing N-functionalised carbamate side-chains has been developed. The key steps involved a phase-transfer mediated macrocyclisation to form the ring system as well as a tin-catalysed reaction with isocyanates to introduce the carbamate side-chains. X-Ray crystallography confirmed successful formation of the 1,4,7,10-tetraazacyclododecane ring and N-functionalisation of all the amine centres. Preliminary testing of the biological activity of the compounds revealed significant anti-parasitic activity against bloodstream form African trypanosomes.

A family of 5-deazaflavin derivatives has been synthesised using a two-step convergent strategy. The biological activity of these compounds was evaluated in cells, by assessing their ability to stabilize and activate p53. These compounds may act as low molecular weight inhibitors of the E3 activity of HMD2 in tumours that retain wild-type p53. Importantly, we have demonstrated that the nitro group present in all three of the original lead compounds [1-3 (HL198C-E)] is not essential for observation of this biological activity.

The melanin biosynthetic pathway from tyrosine is a potential target for combating malignant melanoma. N-Acetyl-4-S-cysteaminylphenol 1 is a previously synthesized analogue of tyrosine that probably acts by this pathway. It interferes with cell growth and proliferation via selective oxidation in melanocytes to an oquinone that can alkylate cellular nucleophiles. We previously synthesized a range of analogues of the original lead compound 1 most of which displayed greater cytotoxicity than 1. Eighteen new analogues with the amide group reversed have now been synthesized and tested for antimelanoma activity. Most of these reverse amides showed greater cytotoxicity than N-acetyl-4-S-cysteaminylphenol towards five representative melanoma cell lines. The highest cytotoxicity was observed for the piperidine and hexamethyleneimine derivatives 7, 8, 12, 13, and 17 and the catechol 18. The most active compound, 7, had cytotoxicity comparable to cisplatin against the five melanoma cell lines. The moderate activity of 7 and 18 against SK-Mel-24 (non-tyrosinase containing) and an ovarian cell line suggests that interference with the melanin pathway may not be the only mode of action of these compounds. Assays of some of the compounds as substrates for tyrosinase showed that the catechol 18 was the best substrate and that the piperidine derivative 7 was the best substrate of the phenolic compounds synthesized.

We are seeking to develop more effective alkylating agents as antitumour agents. In previous work conformationally restricted nitrogen mustards were synthesised containing piperidine or pyrrolidine rings. The free bases were designed to be bifunctional alkylating agents via aziridinium ion formation and the effects of varying the distances between the two alkylating sites were studied. Some efficient cross-linkers of naked DNA were prepared but few of these compounds exhibited significant cytotoxicity in human tumour cells in vitro. We have extended this work by making tri- and tetra-azamacrocyclic compounds containing two to four potential alkylating sites. Most of these compounds were powerful DNA alkylating agents and showed cytotoxicity (IC(50) values 6-100microM) comparable with chlorambucil (45microM) and melphalan (8.5microM). In particular the cyclen derivative 2a was more than 10(4) times more effective at cross-linking DNA (2a XL(50)<<10nM) than chlorambucil (XL(50) 100microM), and showed significant cytotoxicity in human tumour cells in vitro.

Interference with the biosynthetic pathway to melanin may be a useful means for developing new chemotherapeutic drugs to combat malignant melanoma. N-Acetyl-4-S-cysteaminylphenol (1) is an analogue of tyrosine that is involved in the pathway to melanin. It is probably oxidized selectively in melanocytes to an o-quinone that can alkylate thiol groups on important cellular enzymes, resulting in interference with cell growth and proliferation. We previously synthesized a range of more lipophilic analogues of 1 by independently varying the acyl portion and introducing substitution alpha to the nitrogen. Most of the new compounds displayed greater cytotoxicity than the original lead compound 1. We also made a series of tertiary amides that again showed higher cytotoxicity than 1. In this work three new acetamides and two new cyclohexanecarboxamides containing 4-S-cysteaminylphenol were prepared incorporating both substitution alpha to the nitrogen and different substituents on the nitrogen of the amide in each compound to increase lipophilicity and to reduce further the possibility of hydrolysis of the amides. Most of the new tertiary amides showed greater cytotoxicity towards five representative melanoma cell lines than the parent secondary amide. The highest cytotoxicity against these five cell lines with IC50 values of 1-15 nicroM, comparable to cisplatin, was observed for N-[2[(4-hydroxyphenyl)thio]-1,1-dimethylethyl]-N-methylcyclohexanecarboxamide (8c). The IC50 values of 14.5 and 5.4 microM for this compound against SK-Mel-24 (not containing tyrosinase) and an ovarian cell line, respectively, suggest that interference with the melanin pathway may not be the only mode of action of this new compound. The cyclohexanecarboxamides were better substrates for mushroom tyrosinase (EC 1.14.18.1) than the acetamides.

Tumor hypoxia provides a key difference between healthy and cancerous cells. It can be exploited to produce drug selectivity, offering a reductase-rich environment for prodrug activation. Nitrogen mustard drugs are cytotoxic, but usually unselective. Polyamine mustards are candidates for conversion into hypoxia-selective prodrugs via complexation with metals. Reduction to a less stable complex can free the active drug. The novel Cu(II) complexes of N-mustard derivatives of 1,4,7-triazacyclononane (tacn), 1,4,7,10-tetraazacyclododecane (cyclen), and 1,4,8,11-tetraazacyclotetradecane (cyclam) were assessed in vitro as hypoxia-selective cytotoxins. The cyclen mustard complex showed 24-fold selectivity as a hypoxia-selective bioreductive prodrug, with an IC50 value of 2 microM against the lung tumor cell line A549. Reversible redox behavior and stability of the cyclen-Cu(II) complex in aqueous solution correlated with good hypoxia selectivity. The two other related complexes showed irreversible redox behavior and low aqueous stability and were not hypoxia-selective. The use of macrocyclic nitrogen mustard complexes represents a promising new strategy in the design of hypoxia-selective cytotoxins.

Examples of five classes of diamines were synthesized and tested for antifungal activity. Two classes, the bis(cyclohexylmethyl)diamines and the bis(benzyl)diamines, were most effective in reducing mycelial growth of the oat leaf stripe pathogen Pyrenophora avenae Ito & Kuribay when used at a concentration of 250microM. The bis(benzyl)diamine BBD5 and the hydroxypyridylethylamine HPE2 both reduced powdery mildew infection of barley seedlings by greater than 70% when applied as a post-inoculation spray at 250 microM. Several of the compounds examined, and especially BBD5 and HPE2, reduced the formation of spermidine but greatly increased spermine levels. These changes in P avenae treated with BBD5 and HPE2 were also accompanied by greatly elevated activity of polyamine oxidase. It is suggested that the antifungal activity of these compounds may be related to the accumulation of spermine and specifically to its toxicity.

The synthesis of several thiazolo[4, 5-d]pyrimidines containing a fluorophenyl moiety substituted at different positions and through different bridges is described. Twenty new compounds were prepared and evaluated for their anticancer activity using the USA-NCI in-vitro screening program. Three compounds were found active and their anticancer activity against 60 human tumor cell lines are described in detail.

The biosynthetic pathway to melanin is a realistic target for therapeutic intervention in the development of new drugs to combat malignant melanoma. N-Acetyl-4-S-cysteaminylphenol (1) is an analogue of a biosynthetic intermediate in the pathway to melanin. It probably acts as a prodrug and is oxidized selectively in melanocytes to an o-quinone, which can alkylate cellular nucleophiles resulting in interference with cell growth and proliferation. We previously synthesized a range of more lipophilic analogues of 1 by varying the acyl portion and introducing substitution alpha to the nitrogen. Most of the new compounds displayed greater cytotoxicity than the original lead compound 1. We have now prepared 12 new compounds with varying acyl portions and three different substituents on the nitrogen of the amide in order to increase lipophilicity and to reduce the possibility of hydrolysis of the amides. Most of the tertiary amides showed greater cytotoxicity towards five representative melanoma cell lines than the parent secondary amide. The highest cytotoxicity, comparable to cisplatin, was observed for the benzyl substituted compounds 4, 8, 12, and 16 and the cyclohexylacetamide derivatives 13-15 against these five cell lines. The moderate activity of 13-16 against SK-Mel-24 (non-tyrosinase containing) and an ovarian cell line suggests that interference with the melanin pathway may not be the only mode of action of these new compounds.

Nordihydroguaiaretic acid (NDGA) 1 is a constituent of the creosote bush Larrea divaricata and is well known to be a selective inhibitor of lipoxygenases. NDGA can also inhibit the platelet derived growth factor receptor and the protein kinase C intracellular signalling family, which both play an important role in proliferation and survival of cancers. Moreover, NDGA induces apoptosis in tumour xenografts. Although it is likely to have several targets of action, NDGA is well tolerated in animals. These encouraging results have prompted interest in the compound for clinical study. However, high concentrations of NDGA are required for efficacy and more potent analogues are required. We have synthesized five analogues of NDGA with different lengths of carbon bridge between the two catechol moieties in order to establish the spacing required for optimum anticancer effect and to compare their activities with NDGA. In order to ascertain if the catechol moieties are essential for anticancer activity, we prepared five analogues of NDGA containing only one hydroxyl group on each aromatic ring. NDGA 1, its racemic form 2, the catechol derivatives 5, 6 with five or six carbon atom bridges and the phenol analogues 8-11 with bridges of three to six carbon atoms all showed similar activity, with IC50 values of approximately 3-5 microM against the H-69 small cell lung cancer cell line. Analogues with shorter (3) or longer bridges (7, 12) were much less active. The most potent analogue was the biscatechol with a four-carbon bridge 4 which was > 10 times more active than NDGA and therefore represents a new lead compound in this area. Surprisingly, the tetramethyl ether 14 of this compound was slightly more active than NDGA, but the trihydroxy analogue 13 was less active than NDGA. The conformationally restricted analogue 15 was also less active than NDGA. In summary, simplification of the structure of NDGA by removal of the methyl groups has produced a new lead compound 4, which is >10 times more potent than NDGA as a proliferative inhibitor of H-69 small cell lung cancer cells.

Six novel N,N-dialkyl derivatives of spermidine were synthesised and examined for activity against the oat stripe pathogen Pyrenophora avenae. Two of these spermidine analogues, N,N-dimethyl-N1-(3-aminopropyl)-1,3-diaminopropane trihydrochloride (27) and N,N-dimethyl-N1-(3-aminopropyl)-1,4-diaminobutane trihydrochloride (28), reduced radial extension of P. avenae on plates when used at 2 mM, and caused more substantial reductions in fungal growth in liquid culture when used at 1 mM. Preliminary data suggest that neither compound affected polyamine biosynthesis, determined by following the incorporation of label from ornithine into polyamines and examining intracellular polyamine concentrations in fungal tissue.

N-Acetyl-4-S-cysteaminylphenol 1 is an analogue of a biosynthetic intermediate in the pathway to melanin. It is probably oxidized to an o-quinone which can alkylate cellular nucleophiles resulting in interference with cell growth and proliferation. It is reported to have useful anti-melanoma activity. We previously synthesized a range of analogues of 1 by varying the acyl portion of the amide. A modest increase in melanoma activity against six melanoma cell lines for these analogues could be correlated with increased lipophilicity. Thirteen new analogues of 1 containing two methyl groups at the alpha-position of the amino component and various acyl groups have now been prepared and assessed for anti-melanoma activity against six human melanoma cell lines. Most of the new compounds displayed greater cytotoxicity than the lead compound 1. The highest cytotoxicity against the cell lines was observed for the cyclohexylacetamide 11 followed by the cyclohexylcarboxamide 10 and the 2,2-dimethylpropanamide 6. The IC50 values of the most cytotoxic compound 11 against the cell lines were comparable with those of cisplatin. Small variations in the acyl components of these analogues, such as reducing the ring size, lengthening the carbon chain and reducing the amount of chain branching, resulted in a considerable loss of cytotoxicity. The moderate activity of 6, 10 and 11 against SK-Mel-24 cells (non-tyrosinase containing) and an ovarian cell line suggests that interference with the melanin pathway may not be their only mode of action.

N-(1-Naphthyl)-N'-(3-[(125)I]-iodophenyl)-N'-methylguanidine ([(125)I]-CNS 1261) was synthesized as a potential radioligand to image N-methyl-D-aspartate (NMDA) receptor activation. [(125)I]-CNS 1261 was prepared by radioiodination of N-(1-naphthyl)-N'-(3-tributylstannylphenyl)-N'-methylguanidine using Na(125)I and peracetic acid. [(125)I]-CNS 1261 uptake in vivo reflected NMDA receptor distribution in normal rat brain, whereas in ischemic rat brain, uptake was markedly increased in areas of NMDA receptor activation. Radiolabeled CNS 1261 appears to be a good candidate for further development as a single photon emission computed tomography tracer in the investigation of NMDA receptor activation in cerebral ischemia.

N-Acetyl-4-S-cysteaminylphenol (1) has been shown by Jimbow and co-workers to possess useful antimelanoma activity. It is an analogue of a biosynthetic intermediate in the pathway to melanin and probably acts as a prodrug, being oxidized to an o-quinone which reacts with essential enzymes containing sulphydryl groups resulting in interference with cell growth and proliferation. We have synthesized a range of analogues of 1 by varying the acyl portion of the amide with the intention of increasing the lipophilicity of the compounds. A modest increase in melanoma activity against six melanoma cell lines for these analogues could be correlated with increased lipophilicity. The most active of these compounds, N-[2-[(4-hydroxyphenyl)thiol]ethyl]cyclohexanecarboxamide (9), showed promising selectivity (lack of cytotoxicity) on the non-melanotic cell line SK-Mel-24 and on an ovarian cell line. A significant improvement in antimelanoma activity was observed with a new type of analogue containing three carbon atoms between the sulphur and nitrogen. The most active of these new analogues, N-[3-[(4-hydroxyphenyl)-thiolpropyl]-1-cyclohexanecarboxamide (15), had activity comparable to cisplatin against several cell lines and low cytotoxicity towards the non-melanotic cell line.

In our previous work Knoevenagel condensation of quinoline 2-, 3- and 4-carbaldehyde with malononitrile derivatives was used to produce a series of heteroarylidene malononitrile derivatives. Some of these heteroaromatic tyrphostins were potent inhibitors of the epidermal growth factor (EGF) receptor kinase. This work has now been extended by using 6-, 7-, and 8-quinolinecarbaldehyde to prepare 23 new quinoline-tyrphostins 1-23. Most of these compounds were moderately active against the MCF7 breast cancer cell line. The order of potency was 7- > 6 > 8-substituted quinoline, which indicates that increased activity of the 7-substituted quinolines is associated with electron deficiency at the 7-position in the quinoline ring. The most active compound, 12, formed from 7-quinolinecarbaldehyde and ethyl cyanoacetate, had an IC50 value of 2.3 microM. Compounds 1-23 showed similar IC50 values against the MCF7 and MCF7/ADR cell lines (the latter shows fourfold increased protein tyrosine kinase activity) except for the compounds 1 and 15 formed from 6-quinolinecarbaldehyde and malononitrile and 7-quinolinecarbaldehyde and cyanoacetamide, which showed a significant (11- and 42-fold, respectively) increase in potency against the MCF7/ADR cell line. Furthermore, no association was found between growth inhibition and inhibition of the EGFR protein tyrosine kinase (PTK), using a cell-free assay. In addition, new compounds were prepared from 2- and 4-quinolinecarbaldehyde with extended conjugation in the side chains (24-27) or with methoxypolyethoxyethyl esters in the side chain to increase water solubility (28 and 29). These compounds showed substantial cytotoxicity, with IC50 values in the range 1-25 microM, but similar values were observed against both cell lines. No association was found between inhibition of PTK and growth inhibition, again indicating that their mode of action may not be specific for the EGF receptor.

We are seeking to develop more effective bifunctional alkylating agents as antitumour agents. We previously synthesized conformationally restricted nitrogen mustards containing one piperidine ring, then bispiperidine derivatives were designed and prepared with varying lengths of carbon chain between the two rings and structure-activity relationships in these systems were studied. A bispiperidine with the shortest bridge of two carbon atoms was the most reactive bifunctional alkylating agent. In order to extend this work and investigate the effects of a change in the size of the heterocyclic systems, new bispyrrolidine salts 17-23 with chloromethyl groups at the 2-positions and a bridge between the two nitrogen atoms of 2-8 carbon atoms were synthesized from L-proline so that only the LL-enantiomers were produced. The free bases were designed to be bifunctional alkylating agents via aziridinium ion formation with different distances between the two alkylating sites. All of the bispyrrolidines were efficient cross-linkers of naked DNA apart from those with three-carbon (18) and four-carbon (19) bridges, in contrast to the results with the bispiperidines. A piperazine derivative 24 with two potential alkylating sites was also shown to be an efficient cross-linker, as was an alicyclic compound 25 with six carbon atoms between the two alkylating sites. Compounds 26 and 30 with an extra carbon atom between the nitrogen and the leaving group were not cross-linkers, as expected if aziridinium ion formation is crucial for cross-linking ability. The preformed aziridine 27 with a further alkylating site was an efficient cross-linker. Compounds 28-29 with only one potential alkylating centre were not cross-linkers of DNA. None of the compounds, however, produced significant cytotoxicity in human tumour cells in vitro.

The enzymes N-methylputrescine oxidase (MPO), the tropine-forming tropinone reductase (TRI), the pseudotropine-forming tropinone reductase (TRII), the tropine:acyl-CoA transferase (TAT) and the pseudotropine:acyl-CoA transferase (PAT) extracted from transformed root cultures of Datura stramonium and a Brugmansia candida x aurea hybrid were tested for their ability to accept a range of alternative substrates. MPO activity was tested with N-alkylputrescines and N-alkylcadaverines as substrates. TRI and TRII reduction was tested against a series of N-alkylnortropinones, N-alkylnorpelletierines and structurally related ketones as substrates. TAT and PAT esterification tests used a series of N-substituted tropines, pseudotropines, pelletierinols and pseudopelletierinols as substrates to assess the formation of their respective acetyl and tigloyl esters. The results generally show that these enzymes will accept alien substrates to varying degrees. Such studies may shed some light on the overall topology of the active sites of the enzymes concerned.

The aim of this work was to develop new bifunctional alkylating agents which damage DNA in a selective manner. In order to extend our previously published work on conformationally restricted nitrogen mustards containing one piperidine ring, new bispiperidine derivatives were designed with varying lengths of carbon chain between the two rings and structure-activity relationships in these systems were studied. Thus samples of new bispiperidine salts 22-26 with chloromethyl groups at the 2-positions and a bridge between the two nitrogen atoms of 2-6 carbon atoms were synthesized. The analogous new bis(p-nitrophenylcarbamates) 17-21 were also prepared. The free bases were designed to be bifunctional alkylating agents via aziridinium ion formation with different distances between the two alkylating sites. The bispiperidines 22-24 were shown to alkylate guanines at the 7-position in the major groove of DNA more selectively than melphalan. The bispiperidine 22 with the shortest two carbon bridge was the most reactive but it was less cytotoxic than melphalan in a human colon carcinoma cell line (IC50 value approximately 30 microM) and in a human chronic myeloid leukaemia cell line (IC50 value approximately 12 microM). The most cytotoxic compound in the latter cell line was the carbamate 17, with an IC50 value of approximately 0.3 microM, and carbamates 17, 19 and 20 were most potent in a panel of human ovarian carcinoma cell lines. These compounds also showed circumvention of acquired cisplatin resistance in three paired cell lines. The carbamates 17-21, however, were less efficient at alkylating and cross-linking naked DNA than the bispiperidines 22-26.

(E)-1,4-Diaminobut-2-ene dihydrochloride 1 (unsaturated putrescine) and some N-substituted derivatives of 1 have strong antifungal activity against a variety of plant pathogens. A series of N-alkylated putrescine derivatives was synthesised and evaluated for antimalarial activity in vitro against the asexual, intraerythrocytic stages of Plasmodium falciparum. (E)-N,N,N',N'-Tetraethyl-1,4-diaminobut-2-ene dihydrochloride 3 was the most active N-alkylated putrescine tested. Enhanced in-vitro activity was evident with the N,N'-bisbenzyl derivatives 7 and 11. Useful activity in vivo was observed only when the 7-chloroisoquinolyl moiety was present, as in 12 (an unsaturated analogue of chloroquine).

Two spermidine analogues were synthesised and examined for antifungal activity. Both compounds used as 1 mM post-inoculation sprays reduced infection of barley seedlings by the powdery mildew fungus, Erysiphe graminis f.sp. hordei, infection of broad bean seedlings by the rust fungus, Uromyces viciae-fabae, and infection of apple seedlings by the powdery mildew fungus, Podosphaera leucotricha. Since these fungal pathogens cannot be cultured axenically, the effects of the two spermidine analogues on mycelial growth in vitro, as well as preliminary investigations on polyamine biosynthesis, were undertaken using the oat stripe pathogen, Pyrenophora avenae. Although neither compound affected radial growth of the fungus on plates, both analogues reduced fungal biomass in liquid culture substantially. The two spermidine analogues, used at a concentration of 1 mM, had no significant effect on the conversion of labelled ornithine into polyamines in P. avenae.

Tyrphostins are a series of benzylidenemalononitrile derivatives synthesized by condensing aromatic aldehydes with malononitrile derivatives. The use of heteroaromatic aldehydes in this process has received little attention. Accordingly, 27 tyrphostins containing a 2-, 3- or 4-substituted quinoline moiety were synthesized, of which 21 are novel compounds Compounds containing the 2-aminoethene-1, 1-dinitrile moiety in each series were the most potent inhibitors of the EGF receptor kinase in a cell-free enzyme assay (compounds 2, 11 and 20), having IC50 values of 1.7, 27.0 and 4.7 microM respectively. For each R group substitution the order of potency was 2-quinolines > 4-quinolines > 3-quinolines. Compounds 2, 11 and 20 were unable to inhibit the epidermal growth factor (EGF) receptor autophosphorylation in intact cells; however, they were able to inhibit the EGF-dependent phosphorylation of a 50 kDa protein. These three compounds were able to inhibit EGF-dependent proliferation in a fibroblast cell more efficiently than serum-stimulated proliferation, suggesting that their mechanism of action may be linked to the EGF receptor signalling pathway. Compound 2 exhibited a degree of cell line selectivity in the US National Cancer Institute in vitro human tumour cell line panel. The majority of non-small cell lung cancer lines were relatively resistant to compound 2, while most of the colon, CNS, melanoma and renal lines were relatively sensitive. Further work is required to elucidate the mechanism of action of this interesting group of substituted-quinoline compounds and to determine whether for compounds 2, 11 and 20 this is related to inhibition of EGF receptor function.

Bioreducible anti-tumour agents are prodrugs which are intended to be inactive in normal cells, but are able to undergo metabolic reduction in cancer cells to produce toxic species that can damage biomolecules. A series of N-oxides of heterocyclic aliphatic amines were designed and prepared as mentioned below as bioreducible drugs based on the reported anti-cancer activity of 2,6-bis(halomethyl)piperidines. In order to study structure-activity relationships in these conformationally restricted nitrogen mustards, samples of cis- and trans-2,6-dihydroxymethyl-N-methylpiperidine were prepared and converted into a number of carbamate or halogen derivatives. The free bases were designed to be bifunctional alkylating agents via aziridinium ion formation. The corresponding N-oxides were also prepared for comparison in cytotoxicity tests. In total, 21 new compounds were synthesized plus cis-N-methyl-2,6-bis(chloromethyl)-piperidine (prepared previously but lacking spectroscopic data) and tested against two human colon carcinoma cell lines, HT 29 (high DT-diaphorase) and BE (no DT-diaphorase), under oxic and hypoxic conditions. The majority of the free bases were equally toxic against both cell lines. The most toxic compounds were cis- and trans-N-methyl-2,6-bis(bromomethyl)piperidine with oxic IC50 values between 6 and 11 microM against both cell lines. The N-oxides were relatively non-toxic under both oxic and hypoxic conditions apart from the N-oxide of trans-N-methyl-2,6-bis(bromomethyl)-piperidine. Their low toxicity suggested that the N-oxides are not reduced under hypoxic conditions. We conclude that: (i) 2,6-disubstituted N-methylpiperidine derivatives are chemically versatile cytotoxic entities that are suitable for prodrugging to enhance their therapeutic selectivity; and (ii) N-oxide prodrugs of these compounds are deactivated chemically and display reduced cytotoxicity compared to the parent amines but are apparently not reduced under hypoxic conditions. At least in the colorectal cell lines tested the latter issue would need to be addressed by modifying the redox properties in future work to progress this approach.

A series of 36 nitrothiophene tyrphostins were synthesized, 32 of which were novel structures. Their ability to inhibit the epidermal growth factor (EGF) receptor tyrosine kinase was assessed in a cell-free assay. Compounds containing a dinitrile, 2-aminoethene-1, 1-dinitrile or a thioamide group were good inhibitors of the receptor tyrosine kinase. Although anti-proliferative and cytotoxic activity was seen, no evidence of inhibition of EGF receptor autophosphorylation in intact cells was observed. The compounds showed no preferential inhibition of EGF-dependent proliferation of fibroblasts transfected with the EGF receptor. Furthermore, in a panel of squamous cell carcinoma cell lines with varying levels of EGF receptor expression, there was no selective cell kill of lines with the highest EGF receptor expression. The 2-nitro-5-substituted-thiophenes and the 2-nitro-3-substituted-thiophenes showed reduction potentials falling within the range likely to be reduced by cellular reducing agents, while the 2-nitro-4-substituted-thiophenes and 4-nitro-2-substituted-thiophenes did not. Compounds from the 2-nitro-5-substituted-thiophene series were shown to induce DNA damage, while no evidence of DNA damage was demonstrated with compounds from the 2-nitro-4-substituted-thiophene series. The 2-nitro-5-substituted-thiophene compound 4 showed significant tumour-type selectivity in the US National Cancer Institute human tumour cell line panel. The leukaemia cell lines were particularly sensitive to the compound, as were the majority of the colon cancer, melanoma and breast cancer cell lines, while the central nervous system-derived lines and the non-small cell lung cancer lines were particularly resistant. Further work is required to determine the precise mechanisms involved in these effects.

Simplified procedures for assaying and purifying dihydrodipicolinate synthase (EC 4.2.1.52), the first enzyme of the lysine biosynthetic pathway, have been developed and electrospray ionization m.s. has been used to observe the imine intermediate with pyruvate and to investigate the reaction of the enzyme with bromopyruvate and fluoropyruvate.

A series of benzylidenemalononitrile derivatives previously synthesized by condensing aromatic aldehydes with malononitrile derivatives are known as tyrphostins. In this study, 32 tyrphostins were synthesized, 19 of which are novel compounds. Both hydroxylated derivatives and compounds containing heteroaromatic moieties were prepared. We have confirmed and extended the observation that the tyrphostins displayed an enhancement in their ability to inhibit the epidermal growth factor (EGF) receptor tyrosine kinase domain as the number of hydroxyl groups on the aromatic portion was increased. IC50 values of 1-5 microM were readily achieved. Some inhibitory activity was seen with the heteroaromatic structures, with two compounds exhibiting IC50 values of 56 and 77 microM. However, these derivatives were poor inhibitors of the EGF receptor tyrosine kinase activity as compared to the hydroxylated derivatives. The ability of the 32 tyrphostins synthesized in the present study to inhibit proliferation of a human breast adenocarcinoma cell line (MCF-7) was determined using [3H]thymidine incorporation as a measure of DNA synthesis. Some of the compounds containing pyridine, imidazole or thiophene portions displayed antiproliferative activity comparable to that of tyrphostins prepared from 3,4,5-trihydroxybenzaldehyde. The lack of inhibitory effect of these heteroaromatic compounds on the EGF receptor tyrosine kinase activity suggests that their antiproliferative activity is not related to inhibition of EGF receptor function. As the growth of the MCF-7 cell line is governed by other factors, such as the insulin-like growth factors (IGFs) and oestradiol, it is also still to be established whether the antiproliferative activity of the hydroxylated tyrphostins is directly related to inhibition of the EGF receptor tyrosine kinase activity.

Tyrosine kinases are associated with the cytoplasmic domains of growth factor receptors as well as oncoproteins and many have the potential to cause transformation if mutated or hyperexpressed. Tyrosine kinases therefore represent an excellent target for the development of cancer drugs. A large number of inhibitors have now been identified and many show promising cytostatic activity, particularly using in vitro models. Some in vivo activity has been reported. Progress with various structural classes is reviewed. It is not clear whether specific or broad spectrum tyrosine kinase inhibitors should be developed as potential anticancer drugs. It does seem likely, however, that tyrosine inhibitors will enter clinical trial in cancer patients.

The harmonization of biosynthetic pathways with organic reaction mechanisms has relied heavily on stereochemical studies. The field of biosynthesis of pyrrolizidine alkaloids exemplifies these connections through a wide range of common organic reactions including oxidation condensation, and decarboxylation. Further, the applications of biogenetic concepts and enzyme-catalysed reactions to synthesis are illustrated. The results are exciting, not only for their intrinsic scientific interest, but because they point the way to using plant enzymes to recognise structurally modified biosynthetic intermediates and hence open routes to the synthesis of new compounds that would otherwise be difficult to obtain.

Isocratic reverse-phase analytical HPLC has been used to examine naturally occurring imidazoles of rat brain. Elution of brain extracts with a phosphate buffer mobile phase from columns packed with Hypersil ODS (5 microns) resulted in good separation of the well-documented brain imidazole-containing dipeptides carnosine and homocarnosine. Measured concentrations corresponded to published values. Several further peaks observed had properties consistent with those of N-acetyl derivatives of compounds related to carnosine and homocarnosine. N-Acetyl forms not commercially available were prepared and their identities verified by nuclear magnetic resonance spectroscopy. A number of these had chromatographic properties identical to those of compounds in brain extracts. Fractions corresponding to some of the peaks were examined using staining systems specific for certain chemical features and compared with results obtained for commercial or synthetic standards. The results of these tests supported the chromatographic data. Thus, chromatographic and microchemical evidence is presented for the existence of N-acetyl forms of histidine, 1-methylhistidine, carnosine, anserine, and homocarnosine in rat brain.