661 research outputs found

    Microchamber Cultures of Bladder Cancer: A Platform for Characterizing Drug Responsiveness and Resistance in PDX and Primary Cancer Cells.

    Get PDF
    Precision cancer medicine seeks to target the underlying genetic alterations of cancer; however, it has been challenging to use genetic profiles of individual patients in identifying the most appropriate anti-cancer drugs. This spurred the development of patient avatars; for example, patient-derived xenografts (PDXs) established in mice and used for drug exposure studies. However, PDXs are associated with high cost, long development time and low efficiency of engraftment. Herein we explored the use of microfluidic devices or microchambers as simple and low-cost means of maintaining bladder cancer cells over extended periods of times in order to study patterns of drug responsiveness and resistance. When placed into 75 µm tall microfluidic chambers, cancer cells grew as ellipsoids reaching millimeter-scale dimeters over the course of 30 days in culture. We cultured three PDX and three clinical patient specimens with 100% success rate. The turn-around time for a typical efficacy study using microchambers was less than 10 days. Importantly, PDX-derived ellipsoids in microchambers retained patterns of drug responsiveness and resistance observed in PDX mice and also exhibited in vivo-like heterogeneity of tumor responses. Overall, this study establishes microfluidic cultures of difficult-to-maintain primary cancer cells as a useful tool for precision cancer medicine

    Proteostasis by STUB1/HSP70 complex controls sensitivity to androgen receptor targeted therapy in advanced prostate cancer.

    Get PDF
    Protein homeostasis (proteostasis) is a potential mechanism that contributes to cancer cell survival and drug resistance. Constitutively active androgen receptor (AR) variants confer anti-androgen resistance in advanced prostate cancer. However, the role of proteostasis involved in next generation anti-androgen resistance and the mechanisms of AR variant regulation are poorly defined. Here we show that the ubiquitin-proteasome-system (UPS) is suppressed in enzalutamide/abiraterone resistant prostate cancer. AR/AR-V7 proteostasis requires the interaction of E3 ubiquitin ligase STUB1 and HSP70 complex. STUB1 disassociates AR/AR-V7 from HSP70, leading to AR/AR-V7 ubiquitination and degradation. Inhibition of HSP70 significantly inhibits prostate tumor growth and improves enzalutamide/abiraterone treatments through AR/AR-V7 suppression. Clinically, HSP70 expression is upregulated and correlated with AR/AR-V7 levels in high Gleason score prostate tumors. Our results reveal a novel mechanism of anti-androgen resistance via UPS alteration which could be targeted through inhibition of HSP70 to reduce AR-V7 expression and overcome resistance to AR-targeted therapies

    The immune cell landscape in kidneys of patients with lupus nephritis.

    Get PDF
    Lupus nephritis is a potentially fatal autoimmune disease for which the current treatment is ineffective and often toxic. To develop mechanistic hypotheses of disease, we analyzed kidney samples from patients with lupus nephritis and from healthy control subjects using single-cell RNA sequencing. Our analysis revealed 21 subsets of leukocytes active in disease, including multiple populations of myeloid cells, T cells, natural killer cells and B cells that demonstrated both pro-inflammatory responses and inflammation-resolving responses. We found evidence of local activation of B cells correlated with an age-associated B-cell signature and evidence of progressive stages of monocyte differentiation within the kidney. A clear interferon response was observed in most cells. Two chemokine receptors, CXCR4 and CX3CR1, were broadly expressed, implying a potentially central role in cell trafficking. Gene expression of immune cells in urine and kidney was highly correlated, which would suggest that urine might serve as a surrogate for kidney biopsies

    Selective detection of histologically aggressive prostate cancer

    Full text link
    BACKGROUND: Limited survival benefit and excess treatment because of prostate‐specific antigen (PSA) screening in randomized trials suggests a need for more restricted selection of prostate biopsy candidates by discerning risk of histologically aggressive versus indolent cancer before biopsy. METHODS: Subjects undergoing first prostate biopsy enrolled in a multicenter, prospective cohort of the National Cancer Institute Early Detection Research Network (N = 635) were analyzed to develop a model for predicting histologically aggressive prostate cancers. The control arm of the Prostate Cancer Prevention Trial (N = 3833) was used to validate the generalization of the predictive model. RESULTS: The Early Detection Research Network cohort was comprised of men among whom 57% had no cancer, 14% had indolent cancer, and 29% had aggressive cancer. Age, body mass index, family history of prostate cancer, abnormal digital rectal examination (DRE), and PSA density (PSAD) were associated with aggressive cancer (all P 0.1 ng/mL/cc or abnormal DRE. When PSAD is <0.1 ng/mL/cc, family history or obesity can identify biopsy candidates. CONCLUSIONS: A predictive model incorporating age, family history, obesity, PSAD, and DRE elucidates criteria whereby ¼ of prostate biopsies can be averted while retaining high sensitivity in detecting aggressive prostate cancer. Cancer 2011. © 2011 American Cancer Society. A predictive model incorporating age, family history, obesity, prostate‐specific antigen density, and digital rectal examination has been proposed in detecting aggressive prostate cancer. Using these criteria, ¼ of prostate biopsies can be avoided.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91121/1/26396_ftp.pd

    Nine‐year prostate cancer survival differences between aggressive versus conservative therapy in men with advanced and metastatic prostate cancer

    Get PDF
    BACKGROUND:To the authors' knowledge, the survival benefit of local therapy in the setting of advanced prostate cancer remains unknown. The authors investigated whether prostate-directed treatment with either surgery or radiotherapy versus conservative treatment in the setting of locally advanced or metastatic disease was associated with improved survival within a cohort of men from the Centers for Disease Control and Prevention's (CDC) Breast and Prostate Cancer Data Quality and Patterns of Care Study (CDC POC-BP). METHODS:Men diagnosed with locally advanced (cT3-T4 or N+ and M0) or metastatic prostate cancer were identified. The authors compared survival by treatment type, categorized as conservative (androgen deprivation therapy only) versus aggressive (radical prostatectomy or any type of radiotherapy). Nine-year overall survival and prostate cancer-specific survival were estimated using the Kaplan-Meier method. The Cox proportional hazards model was used to determine factors independently associated with 9-year prostate cancer-specific survival. RESULTS:For men with advanced, nonmetastatic prostate cancer, conservative treatment alone was associated with a 4 times higher likelihood of prostate cancer mortality compared with men treated with surgery (hazard ratio, 4.18; 95% confidence interval, 1.44-12.14). In contrast, no difference was found between conservative versus aggressive treatment after adjusting for covariates for men with metastatic disease. The 9-year prostate cancer-specific survival rate was 27% for those receiving aggressive treatment versus 24% for men undergoing conservative treatment. CONCLUSIONS:The authors did not observe a survival advantage with local therapy in addition to standard androgen deprivation therapy for men with metastatic prostate cancer. However, the results of the current study did affirm advantages in the setting of locally advanced disease. Aggressive local therapy in the setting of metastatic disease needs to be studied carefully before clinical adoption. Cancer 2018;124:1921-8. © 2018 American Cancer Society
    corecore