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19 result(s) for "Jindal, Shalini"
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The androgen receptor is a tumor suppressor in estrogen receptor–positive breast cancer
The role of the androgen receptor (AR) in estrogen receptor (ER)-α-positive breast cancer is controversial, constraining implementation of AR-directed therapies. Using a diverse, clinically relevant panel of cell-line and patient-derived models, we demonstrate that AR activation, not suppression, exerts potent antitumor activity in multiple disease contexts, including resistance to standard-of-care ER and CDK4/6 inhibitors. Notably, AR agonists combined with standard-of-care agents enhanced therapeutic responses. Mechanistically, agonist activation of AR altered the genomic distribution of ER and essential co-activators (p300, SRC-3), resulting in repression of ER-regulated cell cycle genes and upregulation of AR target genes, including known tumor suppressors. A gene signature of AR activity positively predicted disease survival in multiple clinical ER-positive breast cancer cohorts. These findings provide unambiguous evidence that AR has a tumor suppressor role in ER-positive breast cancer and support AR agonism as the optimal AR-directed treatment strategy, revealing a rational therapeutic opportunity. Functional interplay of sex hormones in estrogen receptor–positive breast cancer unveils the therapeutic potential of androgen receptor agonists.
A patient‐derived explant (PDE) model of hormone‐dependent cancer
Breast and prostate cancer research to date has largely been predicated on the use of cell lines in vitro or in vivo. These limitations have led to the development of more clinically relevant models, such as organoids or murine xenografts that utilize patient‐derived material; however, issues related to low take rate, long duration of establishment, and the associated costs constrain use of these models. This study demonstrates that ex vivo culture of freshly resected breast and prostate tumor specimens obtained from surgery, termed patient‐derived explants (PDEs), provides a high‐throughput and cost‐effective model that retains the native tissue architecture, microenvironment, cell viability, and key oncogenic drivers. The PDE model provides a unique approach for direct evaluation of drug responses on an individual patient's tumor, which is amenable to analysis using contemporary genomic technologies. The ability to rapidly evaluate drug efficacy in patient‐derived material has high potential to facilitate implementation of personalized medicine approaches. This study describes an innovative preclinical model that has significant potential to accelerate translational cancer research outcomes. Breast and prostate tumors were cultured as patient‐derived explants (PDE), in a way that sustains the native tissue architecture, microenvironment, cell viability, and steroid receptor signaling. PDEs were responsive to hormones, therapeutic agents, and shRNA while in culture, allowing direct comparison of treatments within an individual's tumor using high‐throughput molecular approaches, including cistrome profiling.
Small Glutamine-Rich Tetratricopeptide Repeat-Containing Protein Alpha (SGTA) Ablation Limits Offspring Viability and Growth in Mice
Small glutamine-rich tetratricopeptide repeat-containing protein α (SGTA) has been implicated as a co-chaperone and regulator of androgen and growth hormone receptor (AR, GHR) signalling. We investigated the functional consequences of partial and full Sgta ablation in vivo using Cre-lox Sgta -null mice. Sgta +/− breeders generated viable Sgta −/− offspring, but at less than Mendelian expectancy. S gta −/− breeders were subfertile with small litters and higher neonatal death ( P  < 0.02). Body size was significantly and proportionately smaller in male and female Sgta −/− (vs WT, Sgta +/− P  < 0.001) from d19. Serum IGF-1 levels were genotype- and sex-dependent. Food intake, muscle and bone mass and adiposity were unchanged in Sgta −/− . Vital and sex organs had normal relative weight, morphology and histology, although certain androgen-sensitive measures such as penis and preputial size and testis descent, were greater in Sgta −/− . Expression of AR and its targets remained largely unchanged, although AR localisation was genotype- and tissue-dependent. Generally expression of other TPR-containing proteins was unchanged. In conclusion, this thorough investigation of SGTA-null mutation reports a mild phenotype of reduced body size. The model’s full potential likely will be realised by genetic crosses with other models to interrogate the role of SGTA in the many diseases in which it has been implicated.
OR05-06 The Androgen Receptor Is a Tumour Suppressor in Estrogen Receptor Positive Breast Cancer
There is strong interest in targeting the androgen receptor (AR) in estrogen receptor (ER) positive breast cancer, but widespread confusion exits as to what therapeutic strategy - agonism or antagonism - is appropriate. Current understanding of AR predominantly stems from the field of prostate cancer, where AR is the key oncogenic driver and therapeutic target. An ensuing assumption is that AR promotes malignancy in breast cancer and should be therapeutically antagonised. However, compelling pre-clinical data to support this assumption is lacking. Since estrogen stimulates and androgen inhibits the development of normal breast tissue, we hypothesized that AR acts as a tumour suppressor in the breast and that AR agonism is the appropriate therapeutic strategy for ER-driven breast cancer. We tested this hypothesis using a large suite of cell line and patient-derived explant (PDE) and xenograft (PDX) models of breast cancer, including those that were resistant to current therapies and those harbouring genomic anomalies of ESR1 associated with treatment-resistant disease. Across the diverse models we found compelling evidence that AR agonism, but not antagonism, potently and durably inhibited tumour growth. A signature of AR activity derived from the xenograft models positively predicted disease survival in multiple large clinical cohorts of ER+ breast cancer, out-performing other breast cancer-specific prognostic signatures. We also show that an AR agonist can be combined with current ER target therapies such as Tamoxifen or a CDK4/6 inhibitor to maximize growth inhibition. Mechanistically, agonist-bound AR opposed ER signalling by repositioning ER and the co-activator p300 in the chromatin landscape, resulting in down-regulation of cell cycle genes. Introduction of an AR DNA binding mutant had no effect on ER signalling or estrogen-stimulated growth in breast cancer cells. As part of this study, we have generated consensus AR cistromes representing ER+ breast cancer cell lines and ER+ tumours that provide a new understanding of AR activity and clearly show differences to those associated with prostate cancer cell lines and tumours. In conclusion, our data provides a compelling biological rationale for AR agonism as a therapeutic strategy in multiple, clinically relevant contexts of ER-positive breast cancer. These findings should dispel widespread confusion over the role of AR in ER-driven breast cancer, an issue that currently hinders progress in leveraging modern AR-targeted therapies (e.g. selective androgen receptor modulators) that lack the undesirable side-effects of androgens for clinical benefit.
Human Papillomavirus in Benign Prostatic Hyperplasia and Prostatic Adenocarcinoma Patients
The aim of this study was to determine the prevalence of human papillomavirus (HPV) types in tissue and HPV antibodies in prostatic disease. Prostate tissue samples were collected from 51 patients diagnosed with adenocarcinoma and 11 with benign prostatic hyperplasia (BPH). All tissue samples were confirmed by histology. Plasma samples were available for 52 prostate patients. We investigated HPV DNA prevalence by PCR, and PCR positive samples were HPV type determined by sequencing. Prevalence of antibodies against twenty-seven HPV proteins from fourteen different HPV types was assessed in the plasma samples. The HPV DNA prevalence in the tissue samples was 14% (7/51) for prostate cancer samples and 27% (3/11) for BPHs. HPV-18 was the only type detected in tissue samples (10/62). No significant difference in HPV prevalence between the prostate cancer and BPH samples was found. HPV-positive cells were identified in eight of our thirteen prostate tissue slides (3/3 BPH and 5/10 adenocarcinoma) by in situ hybridisation, and the positive cells were found in epithelial cells and peripheral blood cells. Serology data showed no significant increase in levels of antibodies against any of the HPV-18 proteins tested for in prostatic disease patients. Antibodies against HPV-1, HPV-4, HPV-6 and HPV-11 were significantly higher in the group of males with prostatic disease. Our study did not show an association between prostatic disease and either presence of HPV DNA in samples or previous exposure of high-risk HPV.
Pilot study of Tremelimumab with and without cryoablation in patients with metastatic renal cell carcinoma
Cryoablation in combination with immune checkpoint therapy was previously reported to improve anti-tumor immune responses in pre-clinical studies. Here we report a pilot study of anti-CTLA-4 (tremelimumab) with (n = 15) or without (n = 14) cryoablation in patients with metastatic renal cell carcinoma (NCT02626130), 18 patients with clear cell and 11 patients with non-clear cell histologies. The primary endpoint is safety, secondary endpoints include objective response rate, progression-free survival, and immune monitoring studies. Safety data indicate ≥ grade 3 treatment-related adverse events in 16 of 29 patients (55%) including 6 diarrhea/colitis, 3 hepatitis, 1 pneumonitis, and 1 glomerulonephritis. Toxicity leading to treatment discontinuation occurs in 5 patients in each arm. 3 patients with clear cell histology experience durable responses. One patient in the tremelimumab arm experiences an objective response, the median progression-free survival for all patients is 3.3 months (95% CI: 2.0, 5.3 months). Exploratory immune monitoring analysis of baseline and post-treatment tumor tissue samples shows that treatment increases immune cell infiltration and tertiary lymphoid structures in clear cell but not in non-clear cell. In clear cell, cryoablation plus tremelimumab leads to a significant increase in immune cell infiltration. These data highlight that treatment with tremelimumab plus cryotherapy is feasible and modulates the immune microenvironment in patients with metastatic clear cell histology. Anti-CTLA4 therapy has not been comprehensively explored for the treatment of metastatic renal cell carcinoma (mRCC). Here, in a pilot study of anti-CTLA4 therapy with or without cryoablation in mRCC, the authors report that the combination is feasible and enhances immune infiltration in patients with metastatic clear cell histology.
Immune checkpoint inhibitors plus debulking surgery for patients with metastatic renal cell carcinoma: clinical outcomes and immunological correlates of a prospective pilot trial
Surgical removal of primary tumors reverses tumor-mediated immune suppression in pre-clinical models with metastatic disease. However, how cytoreductive surgery in the metastatic setting modulates the immune responses in patients, especially in the context of immune checkpoint therapy (ICT), is not understood. We report the first prospective, pilot, non-comparative clinical trial (NCT02210117) to evaluate the feasibility, clinical benefits, and immunologic changes of combining three different ICT-containing strategies with cytoreductive surgery or biopsy for patients with metastatic clear cell renal cell carcinoma. Primary safety endpoint of this trial has been met, with 43 patients completing cytoreductive surgery, 36 patients undergoing post-ICT biopsy, and 25 patients without either procedure due to progressive disease or toxicities or withdrawal of consent (total N  = 104). Patients receiving ICT with cytoreductive surgery or biopsy, did not experience additional ICT- or procedure-related toxicities. The median overall survival was 54.7 months for patients who received ICT plus cytoreductive surgery. Immune-monitoring studies demonstrated that cytoreductive surgery increased antigen-presenting dendritic cell population and decreased KDM6B-expressing immune-suppressive myeloid cells in the peripheral blood. This study highlighted the feasibility of combining ICT with cytoreductive surgery in a metastatic setting and demonstrated the potential enhancement of immune responses following ICT plus cytoreductive surgery. Clinical evidence suggests that debulking surgery in patients with metastatic disease could enhance response to immune checkpoint therapy. Here the authors report the results of a clinical trial of immune checkpoint inhibitors plus debulking surgery in patients with metastatic renal cell carcinoma.
Combined CTLA-4 and PD-L1 blockade in patients with chemotherapy-naïve metastatic castration-resistant prostate cancer is associated with increased myeloid and neutrophil immune subsets in the bone microenvironment
BackgroundImmune checkpoint therapy (ICT) has low response rates in patients with metastatic castration-resistant prostate cancer (mCRPC), in part due to few T cells in the tumor microenvironment (TME). Anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) promotes intratumoral T cell infiltration but induces upregulation of PD-1 and programmed death ligand-1 (PD-L1) within the prostate TME. Combined anti-CTLA-4 plus anti-PD-1 can partly overcome this adaptive resistance and was recently shown to augment responses in patients with mCRPC with measurable disease. Although bone is the most common site of metastasis in prostate cancer, patients with bone-predominant disease are frequently excluded from trials because they lack measurable disease, which limits assessment of disease progression and tissue sampling. We therefore designed this study to investigate combined ICT in mCRPC to bone.HypothesisCombined anti-CTLA-4 (tremelimumab) plus anti-PD-L1 (durvalumab) is safe and well tolerated in patients with chemotherapy-naïve mCRPC to bone.Patients and methodsIn this single-arm pilot study, men with chemotherapy-naïve mCRPC to bone received tremelimumab (75 mg intravenous) plus durvalumab (1500 mg intravenous) every 4 weeks (up to four doses), followed by durvalumab (1500 mg intravenous) maintenance every 4 weeks (up to nine doses). The primary endpoint was incidence of adverse events. Secondary endpoints included serum prostate-specific antigen (PSA), progression-free survival (PFS), radiographic PFS (rPFS), and maximal PSA decline.ResultsTwenty-six patients were treated between August 8, 2017 and March 28, 2019. Grade ≥3 treatment-related adverse events (TRAEs) occurred in 11 patients (42%), with no grade 4 or 5 events. TRAEs leading to discontinuation occurred in three patients (12%). PSA decline ≥50% occurred in three patients (12%). Six patients (24%) achieved stable disease for >6 months. At a median follow-up of 43.6 months, median rPFS was 3.7 months (95% CI: 1.9 to 5.7), and median overall survival was 28.1 months (95% CI: 14.5 to 37.3). Post-treatment evaluation of the bone microenvironment revealed transcriptional upregulation in myeloid and neutrophil immune subset signatures and increased expression of inhibitory immune checkpoints.ConclusionsTremelimumab plus durvalumab was safe and well tolerated in patients with chemotherapy-naïve mCRPC to bone, with potential activity in a small number of patients as measured by rPFS. Combination of CTLA-4 and PD-L1 blockade with therapies targeting the myeloid compartment or other inhibitory immune receptors may be necessary to overcome mechanisms of resistance within prostate bone microenvironment.Trial registration numberNCT03204812.
Immune and pathologic responses in patients with localized prostate cancer who received daratumumab (anti-CD38) or edicotinib (CSF-1R inhibitor)
BackgroundThe prostate tumor microenvironment (TME) is immunosuppressive, with few effector T cells and enrichment of inhibitory immune populations, leading to limited responses to treatments such as immune checkpoint therapies (ICTs). The immune composition of the prostate TME differs across soft tissue and bone, the most common site of treatment-refractory metastasis. Understanding immunosuppressive mechanisms specific to prostate TMEs will enable rational immunotherapy strategies to generate effective antitumor immune responses. Daratumumab (anti-CD38 antibody) and edicotinib (colony-stimulating factor-1 receptor (CSF-1R) inhibitor) may alter the balance within the prostate TME to promote antitumor immune responses.HypothesisDaratumumab or edicotinib will be safe and will alter the immune TME, leading to antitumor responses in localized prostate cancer.Patients and methodsIn this presurgical study, patients with localized prostate cancer received 4 weekly doses of daratumumab or 4 weeks of daily edicotinib prior to radical prostatectomy (RP). Treated and untreated control (Gleason score ≥8 in prostate biopsy) prostatectomy specimens and patient-matched pre- and post-treatment peripheral blood mononuclear cells (PBMCs) and bone marrow samples were evaluated. The primary endpoint was incidence of adverse events (AEs). The secondary endpoint was pathologic complete remission (pCR) rate.ResultsTwenty-five patients were treated (daratumumab, n=15; edicotinib, n=10). All patients underwent RP without delays. Grade 3 treatment-related AEs with daratumumab occurred in 3 patients (12%), and no ≥grade 3 treatment-related AEs occurred with edicotinib. No changes in serum prostate-specific antigen (PSA) levels or pCRs were observed. Daratumumab led to a decreased frequency of CD38+ T cells, natural killer cells, and myeloid cells in prostate tumors, bone marrow, and PBMCs. There were no consistent changes in CSF-1R+ immune cells in prostate, bone marrow, or PBMCs with edicotinib. Neither treatment induced T cell infiltration into the prostate TME.ConclusionsDaratumumab and edicotinib treatment was safe and well-tolerated in patients with localized prostate cancer but did not induce pCRs. Decreases in CD38+ immune cells were observed in prostate tumors, bone marrow, and PBMCs with daratumumab, but changes in CSF-1R+ immune cells were not consistently observed with edicotinib. Neither myeloid-targeted agent alone was sufficient to generate antitumor responses in prostate cancer; thus, combinations with agents to induce T cell infiltration (eg, ICTs) will be needed to overcome the immunosuppressive prostate TME.
Assessment of chemical and microbial contamination in groundwater through leaching of sewage waste in Delhi, India
The identification of proxy indicator for groundwater infiltration and bacterial contamination is an important step in managing groundwater resources and hazard assessment. The objective of the present study was to estimate the hydro-chemical data of Khyberpass, Delhi, location to explore the preliminary, chemical and microbial contamination of groundwater samples through setup lysimetric experiments which were mimicking natural field conditions. The calculated mean values of physico-chemical and microbial parameters in control leachate, drain leachate and drain samples exceeded permissible limits of World Health Organization (WHO). All the groundwater samples for preliminary test were found within WHO permissible limits, whereas drain, drain leachate and control leachate exceeded from WHO permissible limits. Physico-chemical contaminations in drain leachate were significantly higher in groundwater samples as electrical conductivity (272 %), total dissolved solid (230 %), total hardness (420 %), alkalinity (166 %), biological oxygen demand (265 %) and chemical oxygen demand (651 %) and dissolved oxygen (87 %). Significantly different values of spread plate count, pour plate count, total coliform and fecal coliform in drain leachate of Khyberpass were recorded as 3.97 × 10 4 , 1.87 × 10 4 , 1.13 × 10 3 and 6.74 × 10 3  CFU/ml, respectively, in the groundwater samples. Lysimetric experiments have shown that while passing the water from soil profile, the maximum population of microbial flora as well as the chemical pollutants which would have been adsorbed to the soil (holding capacity) indicating the compact nature of soil structure, nevertheless some fraction of chemical and microbial pollutants leached down to the aquifer from a point source and diluted entire ecosystem. The unlined drains (non concrete) and unsanitary environmental conditions could be additional risk factors for groundwater contamination.