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1.
Cancer ; 130(10): 1797-1806, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38247317

ABSTRACT

BACKGROUND: Active surveillance (AS) is the preferred strategy for low-risk prostate cancer (LRPC); however, limited data on determinants of AS adoption exist, particularly among Black men. METHODS: Black and White newly diagnosed (from January 2014 through June 2017) patients with LRPC ≤75 years of age were identified through metro-Detroit and Georgia population-based cancer registries and completed a survey evaluating factors influencing AS uptake. RESULTS: Among 1688 study participants, 57% chose AS (51% of Black participants, 61% of White) over definitive treatment. In the unadjusted analysis, patient factors associated with initial AS uptake included older age, White race, and higher education. However, after adjusting for covariates, none of these factors was significant predictors of AS uptake. The strongest determinant of AS uptake was the AS recommendation by a urologist (adjusted prevalence ratio, 6.59, 95% CI, 4.84-8.97). Other factors associated with the decision to undergo AS included a shared patient-physician treatment decision, greater prostate cancer knowledge, and residence in metro-Detroit compared with Georgia. Conversely, men whose decision was strongly influenced by the desire to achieve "cure" or "live longer" with treatment and those who perceived their LRPC diagnosis as more serious were less likely to choose AS. CONCLUSIONS: In this contemporary sample, the majority of patients with newly diagnosed LRPC chose AS. Although the input from their urologists was highly influential, several patient decisional and psychological factors were independently associated with AS uptake. These data shed new light on potentially modifiable factors that can help further increase AS uptake among patients with LRPC.


Subject(s)
Prostatic Neoplasms , Watchful Waiting , Aged , Humans , Male , Middle Aged , Black or African American/statistics & numerical data , Cohort Studies , Georgia/epidemiology , Michigan/epidemiology , Prostatic Neoplasms/therapy , Prostatic Neoplasms/epidemiology , White/statistics & numerical data
2.
BMJ Open ; 12(9): e063409, 2022 09 21.
Article in English | MEDLINE | ID: mdl-36130763

ABSTRACT

PURPOSE: The 'DSD Pathways' study was initiated to assess health status and patterns of care among people enrolled in large integrated healthcare systems and diagnosed with conditions comprising the broad category of disorders (differences) of sex development (DSD). The objectives of this communication are to describe methods of cohort ascertainment for two specific DSD conditions-classic congenital adrenal hyperplasia with 46,XX karyotype (46,XX CAH) and complete androgen insensitivity syndrome (CAIS). PARTICIPANTS: Using electronic health records we developed an algorithm that combined diagnostic codes, clinical notes, laboratory data and pharmacy records to assign each cohort candidate a 'strength-of-evidence' score supporting the diagnosis of interest. A sample of cohort candidates underwent a review of the full medical record to determine the score cutoffs for final cohort validation. FINDINGS TO DATE: Among 5404 classic 46,XX CAH cohort candidates the strength-of-evidence scores ranged between 0 and 10. Based on sample validation, the eligibility cut-off for full review was set at the strength-of-evidence score of ≥7 among children under the age of 8 years and ≥8 among older cohort candidates. The final validation of all cohort candidates who met the cut-off criteria identified 115 persons with classic 46,XX CAH. The strength-of-evidence scores among 648 CAIS cohort candidates ranged from 2 to 10. There were no confirmed CAIS cases among cohort candidates with scores <6. The in-depth medical record review for candidates with scores ≥6 identified 61 confirmed cases of CAIS. FUTURE PLANS: As the first cohort of this type, the DSD Pathways study is well-positioned to fill existing knowledge gaps related to management and outcomes in this heterogeneous population. Analyses will examine diagnostic and referral patterns, adherence to care recommendations and physical and mental health morbidities examined through comparisons of DSD and reference populations and analyses of health status across DSD categories.


Subject(s)
Adrenal Hyperplasia, Congenital , Androgen-Insensitivity Syndrome , Adrenal Hyperplasia, Congenital/diagnosis , Adrenal Hyperplasia, Congenital/psychology , Adrenal Hyperplasia, Congenital/therapy , Androgen-Insensitivity Syndrome/diagnosis , Androgen-Insensitivity Syndrome/psychology , Child , Cohort Studies , Health Status , Humans , Male , Sexual Development
3.
J Int AIDS Soc ; 24(12): e25859, 2021 12.
Article in English | MEDLINE | ID: mdl-34911162

ABSTRACT

INTRODUCTION: We previously showed that the rectal mucosal immune environment among men who have sex with men (MSM) engaging in condomless receptive anal intercourse (CRAI) is immunologically distinct from that of men who do not engage in anal intercourse (AI). Here, we further examined these differences with quantitative immunohistochemistry to better understand the geographic distribution of immune markers of interest. METHODS: We enrolled a cohort of MSM engaging in CRAI (n = 41) and men who do not engage in AI (n = 21) between October 2013 and April 2015. Participants were healthy, HIV-negative men aged 18-45 from the metro Atlanta area. We performed rectal mucosal sampling via rigid sigmoidoscopy during two study visits separated by a median of nine weeks and timed with sexual activity for MSM engaging in CRAI. We used standardized, automated immunohistochemistry and quantitative image analysis to investigate the rectal mucosal distribution of neutrophils (MPO), IL-17-producing cells (IL-17) and Tregs (FOXP3) in the lamina propria, and cellular proliferation (Ki67) and adherens junction protein (E-cadherin) in the epithelium. We examined associations between biomarker expression and the rectal mucosal microbiota composition by 16s rRNA sequencing. RESULTS: Relative to the colonic crypt base, IL-17, FOXP3, and MPO expression increased towards the rectal lumen, while Ki67 decreased and E-cadherin was more uniformly distributed. Throughout the rectal mucosa distribution examined, MSM engaging in CRAI had higher mean lamina propria MPO expression (p = 0.04) and epithelial Ki67 (p = 0.04) compared to controls. There were no significant differences in IL-17, FOXP3 or E-cadherin expression. We found no significant associations of the five biomarkers with the global rectal microbiota composition or the individual taxa examined. CONCLUSIONS: Understanding the mucosal distribution of inflammatory mediators can enhance our knowledge of the earliest events in HIV transmission. Neutrophil enrichment and crypt epithelial cell proliferation likely represent sub-clinical inflammation in response to CRAI in the rectal mucosa of MSM, which could increase the risk for HIV acquisition. However, the contributory role of the microbiota in mucosal inflammation among MSM remains unclear. HIV prevention may be enhanced by interventions that reduce inflammation or capitalize on the presence of specific inflammatory mechanisms during HIV exposure.


Subject(s)
HIV Infections , Sexual and Gender Minorities , Biomarkers , Georgia , Homosexuality, Male , Humans , Inflammation , Male , RNA, Ribosomal, 16S , Sexual Behavior
4.
Breast Cancer Res ; 23(1): 103, 2021 11 04.
Article in English | MEDLINE | ID: mdl-34736510

ABSTRACT

BACKGROUND: Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that facilitates the adaptation of cancer cells to hypoxic conditions and may be prognostic of breast cancer recurrence. We evaluated the association of HIF-1α expression with breast cancer recurrence, and its association with timing of breast cancer recurrence. METHODS: In this population-based case-control study, we included women diagnosed with stage I-III breast cancer between 1985 and 2001, aged 35-69 years, registered in the Danish Breast Cancer Group. We identified 541 cases of breast cancer recurrence among women with estrogen receptor (ER)-positive disease who were treated with tamoxifen for at least 1 year (ER+ TAM+). We also enrolled 300 breast cancer recurrence cases among women with ER-negative disease, not treated with tamoxifen, who survived at least 1 year (ER-/TAM-). Controls were recurrence-free breast cancer patients at the time of case diagnosis, matched to recurrence cases on ER/TAM status, date of surgery, menopausal status, cancer stage, and county of residence. Expression of HIF-1α was measured by immunohistochemistry on tissue microarrays. We fitted logistic regression models to compute odds ratios (ORs) and 95% confidence intervals (CIs) associating HIF-1α expression with recurrence, and with timing of recurrence. RESULTS: HIF-1α expression was observed in 23% of cases and 20% of controls in the ER+/TAM+ stratum, and in 47% of cases and 48% of controls in the ER-/TAM- stratum. We observed a near-null association between HIF-1α expression in both ER/TAM groups (ER+/TAM+ OR = 1.21, 95%CI 0.88, 1.67 and ER-/TAM- OR = 0.97, 95%CI 0.68, 1.39). HIF-1α expression was not associated with time to recurrence among women in the ER+/TAM+ stratum, but was associated with early recurrence among women in the ER-/TAM- stratum. CONCLUSION: In this study, HIF-1α expression was not associated with breast cancer recurrence overall but may be associated with early recurrence among women diagnosed with ER- breast cancer.


Subject(s)
Breast Neoplasms/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Neoplasm Recurrence, Local , Adult , Aged , Biomarkers, Tumor/metabolism , Breast Neoplasms/drug therapy , Breast Neoplasms/epidemiology , Breast Neoplasms/pathology , Case-Control Studies , Denmark/epidemiology , Drug Resistance, Neoplasm , Female , Humans , Middle Aged , Odds Ratio , Receptors, Estrogen/metabolism , Tamoxifen/therapeutic use
5.
Cancer Prev Res (Phila) ; 14(1): 65-76, 2021 01.
Article in English | MEDLINE | ID: mdl-32917645

ABSTRACT

Increased COX-2 and decreased 15-hydroxyprostaglandin dehydrogenase (15-HPGD) expression promote prostaglandin-mediated inflammation and colorectal carcinogenesis. Experimental studies suggest that vitamin D and calcium may inhibit these pathways, but their effects on colorectal tissue COX-2 and 15-HPGD expression in humans are unknown. We tested the effects of supplemental vitamin D (1,000 IU/day) and/or calcium (1,200 mg/day) on COX-2 and 15-HPGD expression in the morphologically normal rectal mucosa from 62 paients with colorectal adenoma in a placebo-controlled chemoprevention trial. We measured biomarker expression using automated IHC and quantitative image analysis at baseline and 1-year follow-up, and assessed treatment effects using mixed linear models. The primary outcome was the COX-2/15-HPGD expression ratio, because these enzymes function as physiologic antagonists. After 1 year of treatment, the mean COX-2/15-HPGD expression ratio in full-length crypts proportionately decreased 47% in the vitamin D group (P = 0.001), 46% in the calcium group (P = 0.002), and 34% in the calcium + vitamin D group (P = 0.03), relative to the placebo group. Among individuals with the functional vitamin D-binding protein isoform DBP2 (GC rs4588*A), the COX-2/15-HPDG ratio decreased 70% (P = 0.0006), 75% (P = 0.0002), and 60% (P = 0.006) in the vitamin D, calcium, and combined supplementation groups, respectively, relative to placebo. These results show that vitamin D and calcium favorably modulate the balance of expression of COX-2 and 15-HPGD-biomarkers of inflammation that are strongly linked to colorectal carcinogenesis-in the normal-appearing colorectal mucosa of patients with colorectal adenoma (perhaps especially those with the DBP2 isoform). PREVENTION RELEVANCE: Supplemental calcium and vitamin D reduce indicators of cancer-promoting inflammation in normal colorectal tissue in humans, thus furthering our understanding of how they may help prevent colorectal cancer.


Subject(s)
Adenoma/prevention & control , Calcium Carbonate/administration & dosage , Colorectal Neoplasms/prevention & control , Intestinal Mucosa/immunology , Vitamin D/administration & dosage , Adenoma/immunology , Adenoma/pathology , Aged , Biomarkers, Tumor/analysis , Biomarkers, Tumor/metabolism , Colon/drug effects , Colon/enzymology , Colon/immunology , Colon/pathology , Colorectal Neoplasms/immunology , Colorectal Neoplasms/pathology , Cyclooxygenase 2/analysis , Cyclooxygenase 2/metabolism , Dietary Supplements , Female , Follow-Up Studies , Humans , Hydroxyprostaglandin Dehydrogenases/analysis , Hydroxyprostaglandin Dehydrogenases/metabolism , Inflammation/diagnosis , Inflammation/drug therapy , Inflammation/immunology , Inflammation/pathology , Intestinal Mucosa/enzymology , Intestinal Mucosa/pathology , Male , Middle Aged , Rectum/drug effects , Rectum/enzymology , Rectum/immunology , Rectum/pathology , Treatment Outcome
6.
Breast Cancer Res ; 22(1): 65, 2020 06 17.
Article in English | MEDLINE | ID: mdl-32552729

ABSTRACT

BACKGROUND: Crown-like structures in breast adipose tissue (CLS-B), composed of necrotic adipocytes encircled by macrophages, are associated with obesity and hypothesized to worsen breast cancer prognosis; however, data are sparse, particularly in multi-racial populations. METHODS: We assessed specimens for CLS-B from 174 African-American and 168 White women with stage I-III breast cancer treated by mastectomy. Benign breast tissue from an uninvolved quadrant was immunohistochemically stained for CD68 to determine CLS-B presence and density (per cm2 of adipose tissue). Demographic and lifestyle factors, collected via medical record review, were analyzed for associations with CLS-B using logistic regression. Multivariable Cox proportional hazards models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between CLS-B and overall (OS) or progression-free (PFS) survival. RESULTS: Detection of any CLS-B was similar between African-American (32%) and White (29%) patients with no evidence of an association between race and CLS-B in multivariable models (OR = 0.82, 95% CI = 0.49-1.36). Detection of CLS-B was associated with obesity (OR = 4.73, 95% CI = 2.48-9.01) and age ≥ 60 years at diagnosis (OR = 1.78, 95% CI = 0.99-3.21). There was some evidence of associations with parity and current smoking status. Detection of CLS-B was not associated with OS (HR = 1.02, 95% CI = 0.55-1.87) or PFS (HR = 0.99, 95% CI = 0.59-1.67). CONCLUSIONS: Our results show a strong, positive association between BMI and CLS-B in non-tumor tissue similar to previous findings. Detection of CLS-B did not vary by race and was not associated with worse OS or PFS.


Subject(s)
Adipose Tissue/pathology , Black or African American , Breast Neoplasms/pathology , White People , Adipose Tissue/metabolism , Adult , Aged , Aged, 80 and over , Breast Neoplasms/metabolism , Breast Neoplasms/mortality , Breast Neoplasms/therapy , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Middle Aged , Obesity/metabolism , Obesity/pathology , Prognosis , Receptors, Estrogen/metabolism , Survival Rate , Young Adult
8.
Mol Carcinog ; 58(7): 1279-1290, 2019 07.
Article in English | MEDLINE | ID: mdl-30938860

ABSTRACT

The physical gut barrier, comprised of a thick mucus layer and the epithelium, plays an important role in defense against microbes and foreign antigens. Calcium and vitamin D may be involved in maintaining the integrity of the intestinal mucosal barrier, the dysfunction of which may lead to endotoxemia and inflammation, and contribute to colorectal carcinogenesis. We investigated supplemental calcium (1200 mg, daily) and/or vitamin D3 (1000 IU daily) effects on intestinal barrier function-related biomarkers in a subset of 105 participants from a large colorectal adenoma recurrence chemoprevention clinical trial. We assessed expression of the tight junction proteins claudin-1 (CLDN1), occludin (OCLD), and mucin-12 (MUC12) in the normal-appearing colorectal mucosa using standardized, automated immunohistochemistry and quantitative image analysis. Following 1 year of treatment, in the calcium relative to the no calcium group, the CLDN1, OCLD, and MUC12 expression increased by 14% (P = 0.17), 23% (P = 0.11), and 22% (P = 0.07), respectively. In secondary analyses, the estimated calcium treatment effects were greater among participants with baseline serum 25-OH-vitamin D concentrations below the median value of 22.69 ng/mL (CLDN1: 29%, P = 0.04; OCLD: 36%, P = 0.06; MUC12: 35%, P = 0.05). There were no biomarker expression changes in the vitamin D3 alone group; however, modest increases were found in the combined calcium/vitamin D3 group. At baseline, obesity, history of a sessile-serrated adenoma, colorectal MIB-1/Ki-67 expression, and a family history of colorectal cancer were associated with CLDN1, OCLD, and MUC12 expression. Our study supports continued investigation of factors that could affect intestinal mucosal barrier integrity relevant to colorectal carcinogenesis.


Subject(s)
Adenomatous Polyposis Coli/pathology , Calcium, Dietary/therapeutic use , Cholecalciferol/therapeutic use , Claudin-1/metabolism , Colorectal Neoplasms/pathology , Mucins/metabolism , Occludin/metabolism , Aged , Biomarkers, Tumor/blood , Dietary Supplements , Feeding Behavior , Female , Humans , Intestinal Mucosa/metabolism , Male , Middle Aged , Surveys and Questionnaires , Tight Junctions/physiology
9.
Acta Oncol ; 58(2): 154-161, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30351173

ABSTRACT

BACKGROUND: Survivin is an inhibitor of apoptosis, and its expression associates with poor outcomes in multiple cancers. It may be a therapeutic target due to its unique expression in cancer cells. METHODS: We estimated the association between nuclear and cytoplasmic survivin expression in primary tumors and breast cancer recurrence. In this case-control study, we included women age 35-69, diagnosed with stage I-III breast cancer between 1985 and 2001, and registered with the Danish Breast Cancer Group. We identified 541 patients with breast cancer recurrence with estrogen receptor-positive disease who were treated with tamoxifen for at least 1 year (ER+/TAM+) and 300 with estrogen receptor-negative carcinomas, not treated with tamoxifen, and who survived at least 1 year (ER-/TAM-). Controls were matched to cases on ER/TAM status, date of surgery, menopausal status, stage and county. Survivin expression was estimated by immunohistochemistry on tissue microarrays. We fit logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) associating nuclear and cytoplasmic survivin expression with recurrence. RESULTS: Associations between nuclear and cytoplasmic survivin expression and breast cancer recurrence were near-null in both ER+/TAM + and ER-/TAM - strata. For the cytoplasmic to nuclear ratio (CNR) of survivin expression, we found a null association in the ER+/TAM + group comparing CNR ≥5 with CNR <5, but an association (OR =2.48, 95% CI: 1.15, 5.31) in the ER-/TAM - group. CONCLUSIONS: Survivin expression was not associated with breast cancer recurrence in this study. The CNR ratio may warrant further investigation especially among ER - tumors.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Neoplasm Recurrence, Local/metabolism , Survivin/metabolism , Adult , Aged , Biomarkers, Tumor/metabolism , Breast Neoplasms/diagnosis , Case-Control Studies , Female , Humans , Immunohistochemistry , Middle Aged , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/pathology , Prognosis , Registries , Risk Factors , Tissue Array Analysis
10.
Cancer Prev Res (Phila) ; 11(11): 707-716, 2018 11.
Article in English | MEDLINE | ID: mdl-30209117

ABSTRACT

Chronic inflammation in the colorectum, a significant contributor to colorectal carcinogenesis, can be triggered by the activation of proinflammatory signaling pathways such as those initiated by Toll-like receptors (TLR) and nuclear factor κB (NF-κB). Although experimental evidence supports calcium and vitamin D potentially modifying these proinflammatory pathways in the colorectum, human data in these regards are scarce. We investigated supplemental calcium (1,200 mg daily) and/or vitamin D3 (1,000 IU daily) effects on inflammatory signaling pathway-related biomarkers in a subset of 105 participants from a colorectal adenoma recurrence chemoprevention clinical trial. We assessed expression of TLR4 and TLR5, which recognize the bacterial components lipopolysaccharides and flagellin, respectively, and phospho-IKKα/ß (pIKKα/ß), a biomarker of inflammation, in the normal-appearing rectal crypt epithelium and stroma using standardized, automated immunohistochemistry and quantitative image analysis. Following 1 year of treatment, TLR4, TLR5, and pIKKα/ß expression in the rectal mucosa did not statistically significantly change with vitamin D or calcium supplementation, taken alone or in combination. Several baseline participant characteristics, including body mass index, history of sessile serrated adenomas, high red/processed meat intake, and high levels of rectal epithelial cell proliferation (as measured by MIB-1/Ki-67), were associated with higher baseline expression of TLRs or pIKKα/ß. Our findings suggest that vitamin D and calcium may have no substantial effect on the investigated biomarkers. However, several modifiable lifestyle factors may be associated with TLRs and pIKKα/ß expression in the normal rectal mucosa, supporting their future investigation as potentially treatable, preneoplastic risk factors for colorectal neoplasms. Cancer Prev Res; 11(11); 707-16. ©2018 AACR.


Subject(s)
Calcium/administration & dosage , Dietary Supplements , Proctitis/diet therapy , Vitamin D/administration & dosage , Adenoma/pathology , Adenoma/prevention & control , Aged , Biomarkers/analysis , Biomarkers/metabolism , Biopsy , Colorectal Neoplasms/pathology , Colorectal Neoplasms/prevention & control , Female , Follow-Up Studies , Gene Expression Regulation/drug effects , Humans , I-kappa B Kinase/immunology , I-kappa B Kinase/metabolism , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Male , Middle Aged , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/prevention & control , Phosphorylation/drug effects , Proctitis/diagnosis , Proctitis/immunology , Proctitis/pathology , Rectum/drug effects , Rectum/metabolism , Rectum/pathology , Signal Transduction/drug effects , Signal Transduction/immunology , Toll-Like Receptors/immunology , Toll-Like Receptors/metabolism , Treatment Outcome
11.
Cancer Epidemiol Biomarkers Prev ; 27(6): 653-659, 2018 06.
Article in English | MEDLINE | ID: mdl-29593009

ABSTRACT

Background: Expression of human paracrine hormones stanniocalcin 1 (STC1) and stanniocalcin 2 (STC2) may potentiate late breast cancer recurrence. We tested the hypothesis that expression of STC1 and STC2 in primary breast tumors is more strongly associated with late versus early recurrences.Methods: A total of 541 estrogen receptor-positive, tamoxifen-treated (ER+/TAM+) and 300 ER-negative, tamoxifen-untreated (ER-/TAM-) breast cancer patients who experienced recurrence within 10 years of primary diagnosis and matched recurrence-free controls were selected from a cohort of 11,251 Danish breast cancer patients diagnosed with stage I, II, or III breast cancer during 1985 to 2001. The association between IHC expression of STC1 and STC2 in primary breast tumor tissue microarrays and breast cancer recurrence was evaluated within median time to recurrence quintiles.Results: The association between STC1 expression, dichotomized as positive or negative, and recurrence was strongly positive for the final time quintile (6-10 years postdiagnosis) in the ER+/TAM+ group [aOR = 2.70; 95% confidence interval (CI): 1.22-5.98]. Regression of the log ORs relating dichotomous STC1 and STC2 expression to recurrence by median time to recurrence (year) resulted in a relatively large positive effect estimate for STC1 (ß = 0.16; 95% CI, -0.03-0.36) and a near-null positive effect estimate for STC2 (ß = 0.04; 95% CI, -0.14-0.21).Conclusions: Our results suggest a stronger association between primary tumor STC1 expression and late recurrence, as opposed to early recurrence, although no clear trend was apparent.Impact: STC1 expression in the primary tumor may potentiate late recurrences, suggesting dormancy pathways that merit further investigation. Cancer Epidemiol Biomarkers Prev; 27(6); 653-9. ©2018 AACR.


Subject(s)
Breast Neoplasms/diagnosis , Glycoproteins/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Neoplasm Recurrence, Local/diagnosis , Adult , Aged , Breast Neoplasms/pathology , Female , Humans , Middle Aged , Neoplasm Recurrence, Local/pathology
12.
Biochem Biophys Res Commun ; 423(3): 564-70, 2012 Jul 06.
Article in English | MEDLINE | ID: mdl-22695118

ABSTRACT

Androgen receptor (AR) is required for the development and progression of prostate cancer (CaP) from androgen-dependence to androgen-resistance. Both corepressors and coactivators regulate AR-mediated transcriptional activity, and aberrant expression or activity due to mutation(s) contributes to changes in AR function in the progression to androgen resistance acquired during hormonal ablation therapies. Primary culture of epithelial cells from androgen-dependent CWR22 and androgen-resistant CWR22R xenograft tumors were used to evaluate the effect of androgens on AR function, and the association with coactivators (SRC-1 and TIF-2) and corepressors (SMRT and NCoR). Both androgen-dependent CWR22 and androgen-resistant CWR22R cells expressed functional AR as the receptor bind ligand with high affinity and increased trafficking to the nuclei in the presence of androgens. However, in the presence of androgens, AR-mediated transcriptional activity in androgen-sensitive CWR22 cells was limited to a 2-fold increase, as compared to a 6-fold increase in androgen-resistance CWR22R cells. In androgen-sensitive CWR22 cells, immunoblot, confocal microscopy, and chromatin immunoprecipitation assays indicated that the androgen bound AR transcriptional initiation complex in the PSA promoter contained corepressor SMRT, resulting in limited receptor transcriptional activity. In contrast, increased AR-mediated transcriptional activity in the CWR22R cells was consistent with decreased expression and recruitment of the corepressors SMRT/NCoR, as well as increased recruitment of the coactivator TIF-2 to the receptor complex. Similar changes in the response to androgens were observed in the LNCaP/C4-2 model of androgen resistance prostate cancer. Thus, altered recruitment and loss of corepressors SMRT/NCoR may provide a mechanism that changes the response of AR function to ligands and contributes to the progression of the advanced stages of human prostate cancer.


Subject(s)
Androgens/metabolism , Gene Expression Regulation, Neoplastic , Nuclear Receptor Co-Repressor 2/metabolism , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Androgens/pharmacology , Animals , Cell Line , Cell Line, Tumor , Disease Progression , Humans , Male , Mice , Neoplasm Transplantation , Nuclear Receptor Co-Repressor 2/genetics , Rabbits
13.
Mol Cancer Ther ; 10(8): 1460-9, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21690228

ABSTRACT

Triple-negative breast cancers, which lack estrogen receptor, progesterone receptor, and HER2/neu overexpression, account for approximately 15% of breast cancers, but occur more commonly in African Americans. The poor survival outcomes seen with triple-negative breast cancers patients are, in part, due to a lack of therapeutic targets. Epidermal growth factor receptor (EGFR) is overexpressed in 50% of triple-negative breast cancers, but EGFR inhibitors have not been effective in patients with metastatic breast cancers. However, mTOR inhibition has been shown to reverse resistance to EGFR inhibitors. We examined the combination effects of mTOR inhibition with EGFR inhibition in triple-negative breast cancer in vitro and in vivo. The combination of EGFR inhibition by using lapatinib and mTOR inhibition with rapamycin resulted in significantly greater cytotoxicity than the single agents alone and these effects were synergistic in vitro. The combination of rapamycin and lapatinib significantly decreased growth of triple-negative breast cancers in vivo compared with either agent alone. EGFR inhibition abrogated the expression of rapamycin-induced activated Akt in triple-negative breast cancer cells in vitro. The combination of EGFR and mTOR inhibition resulted in increased apoptosis in some, but not all, triple-negative cell lines, and these apoptotic effects correlated with a decrease in activated eukaryotic translation initiation factor (eIF4E). These results suggest that mTOR inhibitors could sensitize a subset of triple-negative breast cancers to EGFR inhibitors. Given the paucity of effective targeted agents in triple-negative breast cancers, these results warrant further evaluation.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Breast Neoplasms/metabolism , Quinazolines/pharmacology , Receptor, ErbB-2/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Sirolimus/pharmacology , Animals , Apoptosis/drug effects , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Synergism , ErbB Receptors/antagonists & inhibitors , Female , Humans , Lapatinib , Mice , Mice, Nude , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/antagonists & inhibitors , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
14.
Breast Cancer Res Treat ; 123(1): 139-47, 2010 Aug.
Article in English | MEDLINE | ID: mdl-19921427

ABSTRACT

Zinc-finger enhancer binding protein (ZEB1) is a transcription factor involved in the progression of cancer primarily through promoting epithelial to mesenchymal transition (EMT). ZEB1 represses the expression of E-cadherin by binding to E-box sequences in the promoter, thus decreasing epithelial differentiation. We show that ZEB1 and androgen receptor (AR) cross-talk in triple negative breast cancer cell lines. Chromatin immunoprecipitation analysis demonstrates that ZEB1 binds directly to the E-box located in the AR promoter. ZEB1 suppression by stably transfecting shRNA in a triple negative breast cancer cell line resulted in a decrease of AR mRNA, protein, and AR downstream targets. ZEB1 knockdown in triple negative breast cancer cells sensitized the cells to bicalutamide by reducing migration compared to the control cells. Conversely, blockade of AR signaling with bicalutamide resulted in a suppression of ZEB1 protein expression in two triple negative breast cancer cell lines. Furthermore, using a breast cancer tissue microarray, a majority of triple negative breast cancers exhibit positive staining for both ZEB1 and AR. Taken together, these results indicate that ZEB1 and AR regulate each other to promote cell migration in triple negative breast cancer cells.


Subject(s)
Breast Neoplasms/metabolism , Gene Expression Regulation, Neoplastic , Homeodomain Proteins/metabolism , Receptor Cross-Talk/physiology , Receptors, Androgen/metabolism , Transcription Factors/metabolism , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Movement/genetics , Chromatin Immunoprecipitation , Female , Gene Expression , Homeodomain Proteins/genetics , Humans , Immunoblotting , Immunohistochemistry , Receptor, ErbB-2/biosynthesis , Receptors, Androgen/genetics , Receptors, Estrogen/biosynthesis , Receptors, Progesterone/biosynthesis , Reverse Transcriptase Polymerase Chain Reaction , Tissue Array Analysis , Transcription Factors/genetics , Transcription, Genetic , Zinc Finger E-box-Binding Homeobox 1
15.
Nanomedicine (Lond) ; 4(1): 83-103, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19093898

ABSTRACT

Nanoparticles (NPs) and nanosized objects are being incorporated rapidly into clinical medicine and particularly into the field of medical oncology, including breast cancer. A number of novel methods for breast cancer diagnosis and treatment, which are based on NPs and other nanodevices, are now available for translation into clinical practice. Computer tomography and MRI with iron-based magnetic NPs are promising methods for radiological detection of cancers. Semiconductor fluorescent NPs (quantum dots) are being developed for simultaneous detection and localization of multiple breast cancer biomarkers, enabling the personalization of therapeutic regimens for each patient. Additionally, inorganic NPs can be conjugated with tumor-specific ligands and used for tumor-selective delivery of chemotherapeutic or hormonal agents. NPs bearing tumor-targeted antibodies and oligonucleotides for anticancer gene therapy are a novel and rapidly developing therapeutic approach in oncology. Nab-paclitaxel and liposomal anthracyclines are US FDA-approved NP-based drug-delivery systems that have demonstrated at least equivalent efficacy and decreased toxicity compared with conventional chemotherapeutic agents used in the treatment of breast cancer. This review focuses on recent applications of NPs into predictive oncology of breast cancer with an emphasis placed on the role of inorganic nanosized objects in the diagnosis and treatment of this malignancy.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/therapy , Nanoparticles/therapeutic use , Animals , Female , Humans , Inorganic Chemicals/chemistry , Metal Nanoparticles/chemistry , Nanomedicine/methods , Nanoparticles/chemistry , Nanoparticles/toxicity , Quantum Dots
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