Activity of Aztreonam in Combination with Avibactam, Clavulanate, Relebactam, and Vaborbactam against Multidrug-Resistant Stenotrophomonas maltophilia.

The intrinsic L1 metallo- and L2 serine-ß-lactamases in Stenotrophomonas maltophilia make it naturally multidrug resistant and difficult to treat. There is a need to identify novel treatment strategies for this pathogen, especially against isolates resistant to first-line agents. Aztreonam in combination with avibactam has demonstrated potential, although data on other aztreonam-ß-lactamase inhibitor (BLI) combinations are lacking. Additionally, molecular mechanisms for reduced susceptibility to these combinations have not been explored. The objectives of this study were to evaluate and compare the in vitro activities and to understand the mechanisms of resistance to aztreonam in combination with avibactam, clavulanate, relebactam, and vaborbactam against S. maltophilia A panel of 47 clinical S. maltophilia strains nonsusceptible to levofloxacin and/or trimethoprim-sulfamethoxazole were tested against each aztreonam-BLI combination via broth microdilution, and 6 isolates were then evaluated in time-kill analyses. Three isolates with various aztreonam-BLI MICs were subjected to whole-genome sequencing and quantitative reverse transcriptase PCR. Avibactam restored aztreonam susceptibility in 98% of aztreonam-resistant isolates, compared to 61, 71, and 15% with clavulanate, relebactam, and vaborbactam, respectively. The addition of avibactam to aztreonam resulted in a ≥2-log10-CFU/ml decrease at 24 h versus aztreonam alone against 5/6 isolates compared to 1/6 with clavulanate, 4/6 with relebactam, and 2/6 with vaborbactam. Molecular analyses revealed that decreased susceptibility to aztreonam-avibactam was associated with increased expression of genes encoding L1 and L2, as well as the efflux pump (smeABC). Aztreonam-avibactam is the most promising BLI-combination against multidrug-resistant S. maltophilia Decreased susceptibility may be due to the combination of overexpressed ß-lactamases and efflux pumps. Further studies evaluating this combination against S. maltophilia are warranted.

Contemporary update of prostate cancer staging nomograms (Partin Tables) for the new millennium.

OBJECTIVES: We previously presented nomograms combining preoperative serum prostate-specific antigen (PSA), clinical (TNM) stage, and biopsy Gleason score to provide the likelihood of various final pathologic stages at radical retropubic prostatectomy. The data for the original nomograms were collected from men treated between 1982 and 1996. During the past 10 years, the stage at presentation has shifted, with more men presenting with Stage T1c, Gleason score 5 to 6, and serum PSA levels less than 10.0 ng/mL. In this work, we update the "Partin Tables" with a more contemporary cohort of men treated since 1994 and with revised PSA and Gleason categories. METHODS: Multinomial log-linear regression analysis was used to estimate the likelihood of organ-confined disease, extraprostatic extension, seminal vesicle or lymph nodal status from the preoperative PSA stratified as 0 to 2.5, 2.6 to 4.0, 4.1 to 6.0, 6.1 to 10.0, and greater than 10 ng/mL, clinical (AJCC-TNM, 1992) stage (T1c, T2a, T2b, or T2c), and biopsy Gleason score stratified as 2 to 4, 5 to 6, 3 + 4 = 7, 4 + 3 = 7, or 8 to 10 among 5079 men treated with prostatectomy (without neoadjuvant therapy) between 1994 and 2000 at Johns Hopkins Hospital. The average age was 58 years. RESULTS: In this cohort, more than 60% had T1c, more than 75% had Gleason score of 6, more than 70% had PSA greater than 2.5 and less than 10.0 ng/mL, and more than 60% had organ-confined disease. Nomograms of the robust estimated likelihoods and 95% confidence intervals were developed from 1000 bootstrap analyses. The probability of organ-confined disease improved across the groups, and further stratification of the Gleason score and PSA level allowed better differentiation of individual patients. CONCLUSIONS: These updated "Partin Tables" were generated to reflect the trends in presentation and pathologic stage for men newly diagnosed with clinically localized prostate cancer at our institution. Clinicians can use these nomograms to counsel individual patients and help them make important decisions regarding their disease.

[Unplanned pregnancies in a developed society--a study on a maternity ward in Berlin]. / Zum Problem der ungeplanten Schwangerschaften in einer hoch entwickelten Gesellschaft - Modellstudie auf einer Wochenstation in Berlin.

OBJECTIVE: Unplanned pregnancies are still common in developed societies. Although the medical-technical methods are mainly in use for family planning, other methods - not provided by the medical care system - have an important impact on the occurrence of unplanned pregnancies. Moreover the frequency of their use is not accurately recorded in usual study-protocols. The spread of methods based on the knowledge of physiologic infertility in woman's cycle (further: fertility awareness) and their relation to unplanned pregnancies is to be investigated. METHODS: A survey by way of self-administered questionnaire was conducted between September 1997 and March 1998 on women in a maternity ward in a hospital in Berlin (former East-Berlin, n = 220). The use of family planning methods (with a special focus on fertility awareness) and the planning state of pregnancies were recorded. RESULTS: 33 % of delivered pregnancies were unplanned. In the last year before conception occurred the part of the use of fertility awareness grew from 12 % to 30 % and correspondingly 25 % to 32 % of unplanned pregnancies were connected with these methods. CONCLUSIONS: The blanking-out of fertility awareness in the framework of medical care system leads to a constellation where a considerable part of unplanned pregnancies occurs beyond its range. The adequate solution for this problem should be an incorporation of fertility awareness into the mainstream of family planning.

A cell-based drug delivery system for lung targeting: I. Preparation and pharmacokinetics.

A drug-loaded tumor cell (DLTC) system has been developed for lung metastasis-targeting drug delivery. Doxorubicin was loaded into B16-F10 murine melanoma cells (96 microg/10(6) cells). The loading process led to the death of all the carrier cells. The diameter of DLTC was 15.03+/-2.36 microm (mean +/- SD). The amount and rate of doxorubicin being released from the DLTC mainly depended on the drug loading and carrier cell concentration. Over a 6-month storage in phosphate buffered saline (PBS) at 4 degrees C, the decrease in intracellular drug concentration and the carrier cell number were less than 25% and 5%, respectively. After a bolus injection of 30 microg doxorubicin in either DLTC form or free solution into the mice tail veins, drug deposit in the lung from DLTC was 3.6-fold of that achieved by free drug solution. The latter resulted in higher drug content in liver and spleen. Extensive trypsinization of DLTC reduced its lung targeting effect by 30%, and the density of surface adhesion molecule GM3 on DLTC surface by 25%. In conclusion, this DLTC system demonstrated a lung-targeting activity that may be partially attributed to its specific surface characteristics.

A cell-based drug delivery system for lung targeting: II. Therapeutic activities on B16-F10 melanoma in mouse lungs.

The in vitro and in vivo anticancer activities of doxorubicin-loaded B16-F10 murine melanoma cells (DLTC) were evaluated. DLTC showed similar growth-inhibitory effects against live B16-F10 cells with doxorubicin solution in cell culture system, with the IC50 of 0.11 microM and 0.17 microM, respectively. However, DLTC demonstrated higher effectiveness than the free solution in treating mouse lung cancer caused by live B16-F10 cells. Syngeneic C57BL mice were inoculated intravenously with live B16-F10 cells first, and then received daily treatment of intravenous injections of doxorubicin in either DLTC or free solution form. Compared with the control group treated with phosphate-buffered saline, DLTC eradicated almost all the lung cancer colonies (>99%), while the free solution form reduced the colonies by 61%, when the treatment was given at an early stage. If the treatment started after the establishment of micrometastatic colonies in the mouse lungs, DLTC and free solution treatment resulted in 85% and 30% cancer reduction, respectively. Additional experiments demonstrated that the reduction of lung cancer colonies by DLTC was related to the initial treatment time: the earlier the treatment, the greater the effect. In conclusion, DLTC showed better therapeutic outcomes than free solution form in treating lung cancer of our animal model.

Enhanced immunocompetence by garlic: role in bladder cancer and other malignancies.

Of the many beneficial actions of garlic, inhibition of the growth of cancer is perhaps the most remarkable. Our previous animal studies demonstrated that aged garlic extract was highly effective, and unlike the approved immunotherapy for human bladder cancer, bacillus Calmette--Guérin (BCG), garlic was effective when added to the diet. To elucidate the mechanism of this antitumor effect, the literature describing antitumor and immune-enhancing effects of garlic is reviewed. Garlic can detoxify carcinogens by stimulation of cytochrome P(450) enzymes, antioxidant activity or sulfur compound binding. Studies demonstrate a direct toxic effect of garlic to sarcoma and gastric, colon, bladder and prostate cancer cells in tissue culture, but these effects cannot explain the inhibition of growth of transplanted cancer in animal models. The most likely explanation of this effect is immune stimulation. Comparison of the effects of garlic to BCG immunotherapy reveals many similarities. Both stimulate proliferation of lymphocytes and macrophage phagocytosis, induce the infiltration of macrophages and lymphocytes in transplanted tumors, induce splenic hypertrophy, stimulate release of interleukin-2, tumor necrosis factor-alpha and interferon-gamma, enhance natural killer cell, killer cell and lymphokine-activated killer cell activity. These activities represent effective stimulation of the immune response. Studies suggest that garlic may be useful in preventing the suppression of immune response that is associated with increased risk of malignancy. Data suggest that maintenance of immune stimulation can significantly reduce the risk of cancer. Clinical trials should be initiated to test the hypothesis that the immune stimulation and other beneficial effects of garlic are able to reduce the incidence of cancer.

Metallothionein isoform 1 and 2 gene expression in the human bladder: evidence for upregulation of MT-1X mRNA in bladder cancer.

The goals of this study were to determine the expression of metallothionein isoform 1 and 2 proteins (MT-1 and MT-2) in bladder cancer and then to determine which MT isoform-specific genes promoted the expression of these proteins. Immunohistochemical analysis disclosed no immunoreactivity for MT-1 and MT-2 (designated as MT-1/2 to reflect the nonspecificity of the antibody for the two isoforms) in cells comprising the normal bladder or in nonmalignant bladder disorders, such as cystitis and interstitial cystitis. Immunohistochemical analysis demonstrated that MT-1/2 was overexpressed in all samples of carcinoma in situ and in high-grade bladder cancer, with variable overexpression in low-grade bladder cancer and dysplastic lesions. The intensity and frequency of MT-1/2 staining correlated with the grade of the tumor. The MT-1 and MT-2 proteins are encoded by a family of eight genes (MT-1A, MT-1B, MT-1E, MT-1F, MT-1G, MT-IH, MT-1X, and MT-2A), and reverse transcriptase-polymerase chain reaction was used to determine which genes were expressed in the normal bladder and in bladder cancer. This analysis demonstrated that both normal and cancerous bladder tissue expressed mRNA for the MT-2A and MT-1X genes. The expression of MT-1E mRNA was variable in both normal bladder and bladder cancer specimens. Comparison of expression relative to that of beta-actin demonstrated that the level of MT-1X mRNA was overexpressed greatly in bladder cancer as compared to the level in normal bladder tissue. In contrast, the level of MT-2A mRNA was similar in both the normal and the bladder cancer specimens. The level of MT-1X expression did not vary with tumor grade. These studies suggest that the overexpression of MT-1/2 protein in bladder cancer is a result of the overexpression of the MT-1X gene.

Immunotherapy for bladder cancer.

The primary role of immunotherapy for bladder cancer is to treat superficial transitional cell carcinomas (ie, carcinoma in situ, Ta, and T1). Immunotherapy in the form of bacille Calmette-Guérin (BCG), interferon, bropirimine, keyhole limpet hemocyanin, and gene therapy is intended to treat existing or residual tumor, to prevent recurrence of tumor, to prevent progression of disease, and to prolong survival of patients. Presently, BCG is commonly used and is the most effective immunotherapeutic agent against superficial transitional cell carcinoma. Data support that BCG has a positive impact on tumor recurrence, disease progression, and survival. Proper attention to maintenance schedules, route of administration, dosing, strains, and viability is essential to obtain the maximum benefits of BCG immunotherapy. This review highlights and summarizes the recent advances concerning immunotherapy, with special emphasis on BCG therapy for transitional cell carcinoma.

Efficacy and safety of bacille Calmette-Guérin immunotherapy in superficial bladder cancer.

In the United States, bladder cancer is the fourth most common human malignancy. In the past decade, the incidence of bladder cancer has increased by 36%. However, mortality has declined by 8%. Intravesical chemotherapy was considered to be partially responsible for this improvement in survival, but a recent review of clinical studies shows no reduction in disease progression with intravesical chemotherapy. Fortunately, the results of immunotherapy with bacille Calmette-Guérin (BCG) are quite different, and it is expected that patients treated with optimal BCG treatment regimens will have a long-term reduction in tumor recurrence, tumor progression, and cancer mortality.

Keyhole limpet hemocyanin immunotherapy of bladder cancer: laboratory and clinical studies.

BACKGROUND: Since the serendipitous observation by Olsson in 1974 that patients immunized with 5 mg of keyhole limpet hemocyanin (KLH) had a marked reduction in recurrence of superficial bladder cancer, multiple laboratory and clinical studies have confirmed the efficacy of KLH immunotherapy. RESULTS: In 1981, we reported that KLH immunotherapy reduced tumor growth and prolonged survival in the MBT-2 murine model of transitional cell carcinoma (TCC), and in 1988, Jurincic and co-workers demonstrated that KLH was superior to mitomycin C chemotherapy in preventing bladder tumor recurrence. Subsequent studies using Immucothel (Biosyn), crude KLH, and endotoxin-free KLH confirmed the efficacy of KLH immunotherapy in the MBT-2 murine bladder cancer model (p < 0.05), and resulted in up to 100% survival. CONCLUSIONS: To evaluate the efficacy of KLH immunotherapy in patients, a multicenter clinical trial was performed. Sixty-four patients with CIS or residual stage T(a), T(1) TCC, or both were enrolled in a phase I-II trial of escalating doses of weekly KLH given intravesically for 6 weeks. Patients were followed with cystoscopic examination, urine cytology, and bladder biopsy. Complete response was seen in 50% of patients with CIS, 20% of patients with residual T(a), T(1) TCC, and 33% of patients with both CIS and residual T(a), T(1) TCC. Responses occurred at all doses tested: 0.4, 2, 10 and 50 mg. No significant difference in response according to dose was noted, but optimal overall complete response was seen with a dose of only 2 mg. The toxicity of KLH is minimal. KLH appears to be a safe and highly effective immunotherapy for superficial bladder cancer.

Metallothionein isoform 3 as a potential biomarker for human bladder cancer.

The goal of the present study was to determine if the expression of metallothionein isoform 3 (MT-3) might serve as a biomarker for human bladder cancer. To accomplish this goal, we defined the localization and expression of MT-3 protein and mRNA using fresh and archival biopsy specimens obtained from patients undergoing differential diagnosis for a variety of bladder disorders. We used immunohistochemistry, immunoblot, and RT-PCR analysis to define the localization and expression of MT-3 protein and mRNA. Immunohistochemical analysis disclosed no immunoreactivity for MT-3 in normal bladder cells. The absence of MT-3 expression in the normal bladder was further confirmed by demonstrating that MT-3 mRNA could not be detected using reverse transcriptase-polymerase chain reaction (RT-PCR) or MT-3 protein using immunoblot. Immunohistochemistry also disclosed no immunoreactivity for MT-3 in archival biopsy specimens from patients with interstitial cystitis and related disorders. Immunohistochemical analysis demonstrated that MT-3 was expressed in carcinoma in situ (CIS), high-grade bladder cancer, low-grade bladder cancer, and dysplastic lesions. MT-3 immunostaining was intense in both CIS and high-grade bladder cancer, and low to moderate in low-grade bladder cancer and dysplastic lesions. We determined MT-3 mRNA expression in a subset of these bladder cancer specimens; expression was elevated as compared to that of the housekeeping gene, ss-actin. The cDNA from the RT-PCR reaction primed for MT-3 contained a FokI restriction site, a site unique for MT-3 as compared to other MT family members. In conclusion, this study demonstrates that MT-3 is up-regulated in human bladder cancer and that this up-regulation increases with increasing tumor grade. The finding that MT-3 expression is minimal in normal bladder suggests that MT-3 might be developed into an effective biomarker for bladder cancer.

Management of patients with Bacilli Calmette-Guérin-refractory carcinoma in situ of the urinary bladder: cost implications of a clinical trial for valrubicin.

OBJECTIVE: This study was undertaken to identify the expected first- and second-year clinical costs associated with intravesical valrubicin therapy, using a decision analytic model, for patients with Bacilli Calmette-Guérin (BCG)-refractory carcinoma in situ (CIS) of the urinary bladder. BACKGROUND: Cancer of the urinary bladder is the fourth most common malignancy in men and the sixth most common noncutaneous carcinoma overall. One histopathologic stage of bladder cancer is CIS, for which BCG intravesical immunotherapy is the first-line therapy. Radical cystectomy has been recommended for patients with CIS who do not respond to or become refractory to therapy with BCG. Surgery, however, may not be appropriate for all patients, especially those who are ineligible for the lengthy procedure because of advanced age or comorbidities and those who prefer alternative nonsurgical management. For these groups, intravesical valrubicin therapy is a plausible alternative. METHODS: Models were developed and populated with data from 1 open-label study of 90 patients, information from the medical literature, and input from clinical experts. The analysis was conducted from the payor perspective for direct costs only. RESULTS: Our data indicate that first- and second-year expected costs for valrubicin therapy are $19,912 and $23,496, respectively. Expected cost for radical cystectomy was also evaluated, since some patients may have no other option if drug therapy fails. CONCLUSION: Our cost-consequence analysis and clinical data provide decision-makers with tools to aid in global budgetary projections of fractional and total expected health care costs associated with the management BCG-refractory CIS of the urinary bladder.

The potential application of Allium sativum (garlic) for the treatment of bladder cancer.

Additional studies are needed to identify the active ingredients in Allium Sativum (garlic) that are responsible for the observed antitumor activity and immune stimulation. Garlic seems to detoxify chemical carcinogens and prevent carcinogenesis and can also directly inhibit the growth of cancer cells. Current data suggest that low molecular weight sulfur compounds and protein F4 have immune-stimulation properties. Garlic is reported to stimulate immunity, including macrophage activity, natural killer and killer cells, and LAK cells, and to increase the production of IL-2, TNF, and interferon-gamma. These cytokines are associated with the beneficial Th1 antitumor response, which is characteristic of effective cancer immunotherapies. As is true of BCG, garlic stimulates the proliferation of macrophages and lymphocytes and protects against the suppression of immunity by chemotherapy and ultraviolet radiation. Garlic is clearly not a panacea for cancer, but its broad range of beneficial effects are worthy of serious consideration in clinical trials for the prevention and treatment of cancer.

Maintenance bacillus Calmette-Guerin immunotherapy for recurrent TA, T1 and carcinoma in situ transitional cell carcinoma of the bladder: a randomized Southwest Oncology Group Study.

PURPOSE: Bacillus Calmette-Guerin (BCG) immunotherapy has been widely accepted as the optimal treatment for carcinoma in situ and high grade superficial transitional cell carcinoma. However, controversy remains regarding the role of maintenance therapy, and its long-term effect on recurrence and progression. MATERIALS AND METHODS: All patients in the study had transitional cell carcinoma of the bladder with carcinoma in situ or an increased risk of recurrence. The criteria for increased risk were 2 or more episodes of tumor within the most recent year, or 3 or more tumors within 6 months. At least 1 week following biopsy of carcinoma in situ and resection of any stage Ta or T1 transitional cell tumors 660 patients were started on a 6-week induction course of intravesical and percutaneous Connaught BCG. Three months following initiation of BCG induction therapy 550 consenting patients were stratified by purified protein derivative skin test and the presence of carcinoma in situ, and then randomized by central computer to receive BCG maintenance therapy (maintenance arm) or no BCG maintenance therapy (no maintenance arm). Maintenance therapy consisted of intravesical and percutaneous BCG each week for 3 weeks given 3, 6, 12, 18, 24, 30 and 36 months from initiation of induction therapy. The 384 eligible patients who were disease-free at randomization constitute the primary intent to treat analytic group because they could be followed for disease recurrence. All patients were followed for adverse effects of treatment, recurrence, disease worsening and survival. RESULTS: No toxicities above grade 3 were noted in the 243 maintenance arm patients. The policy of withholding maintenance BCG from patients with increased side effects may have diminished the opportunity to observe severe toxicity. Estimated median recurrence-free survival was 35.7 months (95% confidence interval 25.1 to 56.8) in the no maintenance and 76.8 months (64.3 to 93.2) in the maintenance arm (log rank p<0.0001). Estimated median time for worsening-free survival, defined as no evidence of progression including pathological stage T2 disease or greater, or the use of cystectomy, systemic chemotherapy or radiation therapy, was 111.5 months in the no maintenance and not estimable in the maintenance arm (log rank p = 0.04). Overall 5-year survival was 78% in the no maintenance compared to 83% in the maintenance arm. CONCLUSIONS: Compared to standard induction therapy maintenance BCG immunotherapy was beneficial in patients with carcinoma in situ and select patients with Ta, T1 bladder cancer. Median recurrence-free survival time was twice as long in the 3-week maintenance arm compared to the no maintenance arm, and patients had significantly longer worsening-free survival.