CEACAM6 gene silencing impairs anoikis resistance and suppresses metastasis of pancreatic adenocarcinoma

Introduction: Inadequate or inappropriate cell-substrate contact normally induces a form of apoptotic cell death termed anoikis. Malignant cells are often able to escape anoikis; this feature may contribute to their ability to form metastases. We hypothesized that carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) gene silencing would suppress anoikis resistance in pancreatic cancer cells. Methods: CEACAM6 was analyzed by Northern and Western blot. Anoikis was induced in PANC1, Capan2, MiaPaCa2 and Mia^AR (an anoikis-resistant MiaPaCa2-derived sub-line) by polyHEMA culture and quantified by YO-PRO-1/propidium iodide flow cytometry (anoikis fraction). Caspase activity was quantified by fluorometric profiling and its contribution to anoikis confirmed with caspase inhibitor z-VAD-fmk. CEACAM6 expression was suppressed by siRNA (siCEACAM6). Metastatic ability was determined in an orthotopic nude mouse model. Results: CEACAM6 expression varied between cell lines, over-expression being associated with greater anoikis-resistance and in vivo metastatic ability. siCEACAM6 treatment suppressed native and acquired anoikis -resistance (see table) via increased caspase 3 and 8-acitvity (respective mean activities vs control in MiaPaCa2: 150% and 133%. Mia^AR: 220% and 150%. P < 0.05), an effect abrogated by z-VAD-fmk. Mia^AR metastasis was decreased from 100% of mice (median metastases: 3, range 0-8. n = 6) to 0% (n = 6. P < 0.05). Conclusion: CEACAM6 gene silencing promotes anoikis, reverses acquired anoikis resistance and inhibits metastasis in pancreatic adenocarcinoma. CEACAM6 warrants further investigation as a novel therapeutic target.     

Lentivirus-mediated RNA interference of HMGA1 promotes chemosensitivity to gemcitabine in pancreatic adenocarcinoma.

The high mobility group A1 (HMGA1) proteins are overexpressed in pancreatic cancers. They are architectural nuclear proteins, which regulate expression of multiple genes implicated in the malignant phenotype. In this study, we hypothesized that HMG A1 silencing will promote chemosensitivity in pancreatic adenocarcinoma. We studied highly malignant pancreatic adenocarcinoma cell lines (MiaPaCa2 and PANC1). Lentiviral short-hairpin RNA (shHMGA1) expression vectors targeting HMGA1 were used for generation of lentiviral particles. Stable transfectants were developed after lentiviral transduction. Nuclear expression of HMGA1 was assayed using Western blot analysis. Chemosensitivity to gemcitabine was determined by IC50 analysis. Caspase activity was quantitated using fluorometric caspase profiling. Apoptosis was assessed by flow cytometric analysis. Lentivirus-mediated RNA interference resulted in 90% silencing of HMGA1 expression in each of MiaPaCa2 and PANC1 cell lines. HMGA1 silencing enhanced chemosensitivity to gemcitabine with an approximately 50% reduction in IC50 in each cell line. Lentivirus-mediated HMGA1 silencing promoted the activation of caspases 3, 2, 9, and 8, on exposure to gemcitabine. HMGA1 silencing resulted in reduction in Akt kinase activity. Lentivirus-mediated RNA interference of HMGA1 promoted chemosensitivity to gemcitabine in pancreatic adenocarcinoma. HMGA1 may represent a novel therapeutic target in pancreatic cancer.     

Lentivirus-mediated RNA interference of HMGA1 promotes chemosensitivity to gemcitabine in pancreatic adenocarcinoma

The high mobility group A1 (HMGA1) proteins are overexpressed in pancreatic cancers. They are architectural nuclear proteins, which regulate expression of multiple genes implicated in the malignant phenotype. In this study, we hypothesized that HMG A1 silencing will promote chemosensitivity in pancreatic adenocarcinoma. We studied highly malignant pancreatic adenocarcinoma cell lines (MiaPaCa2 and PANC1). Lentiviral short-hairpin RNA (shHMGA1) expression vectors targeting HMGA1 were used for generation of lentiviral particles. Stable transfectants were developed after lentiviral transduction. Nuclear expression of HMGA1 was assayed using Western blot analysis. Chemosensitivity to gemcitabine was determined by IC50 analysis. Caspase activity was quantitated using fluorometric caspase profiling. Apoptosis was assessed by flow cytometric analysis. Lentivirus-mediated RNA interference resulted in 90% silencing of HMGA1 expression in each of MiaPaCa2 and PANC1 cell lines. HMGA1 silencing enhanced chemosensitivity to gemcitabine with an approximately 50% reduction in IC50 in each cell line. Lentivirus-mediated HMGA1 silencing promoted the activation of caspases 3, 2, 9, and 8, on exposure to gemcitabine. HMGA1 silencing resulted in reduction in Akt kinase activity. Lentivirus-mediated RNA interference of HMGA1 promoted chemosensitivity to gemcitabine in pancreatic adenocarcinoma. HMGA1 may represent a novel therapeutic target in pancreatic cancer. This work was supported by National Institutes of Health grant 1-R01-CA114103 and American Cancer Society grant RSG-04221-01-CCE. S.-S.L. is in receipt of the International Hepato-Pancreato-Biliary Association (IHPBA) Kenneth W. Warren Fellowship, Pancreatic Society of Great Britain and Ireland Traveling Fellowship and Aid for Cancer Research Grant.     

The oncogenic potential of a prostate cancer-derived androgen receptor mutant

BACKGROUND: The role of androgen receptor (AR) mutations in the initiation of prostate cancer (CaP) remains unclear. The purpose of this study was to assess the influence of an AR mutation on prostate tumorigenesis and to determine the resulting molecular alterations. METHODS: Wild-type AR (AR(WT)) or the CaP-derived K580R AR (AR(K580R)) mutant was stably transfected into SV40-immortalized human prostate epithelial pRNS-1-1 cells that lack AR expression and fail to grow in nude mice. The ability of these AR-transfected cell lines to form tumor was investigated in vitro and in vivo. Additionally, gene expression profiling of these cell lines was performed. RESULTS: Compared with the AR(WT), the AR(K580R) induced greater than sixfold increase in colony formation in soft agar. In vivo studies confirmed that the AR(K580R)-transfected pRNS-1-1 cells were able to form tumors in nude mice. Using a combination of microarray and RT-PCR, 29 differentially expressed genes were identified in AR(K580R) cells. It was found that silencing the expression of placental alkaline phosphatase (ALPP) that was upregulated in AR(K580R) cells resulted in significant inhibition of cell growth. Furthermore, the AR(K580R)-transfected pRNS-1-1 cells expressed markedly increased p-Akt and p-p70 S6K. CONCLUSION: The AR(K580R) mutation promoted the malignant transformation of prostate epithelial cells. This was associated with upregulation of ALPP and subsequent activation of the Akt signaling pathway.     

Selective cyclooxygenase-2 inhibitor rofecoxib (vioxx) induces expression of cell cycle arrest genes and slows tumor growth in human pancreatic cancer

Recent studies indicate that cyclooxygenase-2 (COX-2) is overexpressed in pancreatic adenocarcinoma and may play a critical role in this rapidly progressing form of cancer. A human pancreatic adenocarcinoma cell line, Mia PaCa-2, was incubated for 18 hours with 5μ mol/L of rofecoxib (Vioxx), a selective COX-2 inhibitor. Total RNA was isolated and gene expression analyzed by DNA microarray chips. In a separate experiment, athymic mice were orthotopically injected with 7.5 x 10⁵ Mia PaCa-2 cells through a minilaparotomy. After 1 month, laparotomy was repeated to measure tumor size, and mice were randomized to receive reformulated rodent chow containing either 12.5 mg/kg/day of rofecoxib or no drug for 21 days. Tumor growth was assessed by comparing volume before and after treatment. In vitro, rofecoxib decreased gene expression of cyclin D1/PRAD1, a key component of cell cycle progression, while increasing expression of several cell cycle arrest genes, including p21/WAF1, p33/ING, GADD34, and GADD45 (Pμ0.05). In vivo, tumor growth was significantly reduced in treated vs. control mice (Pμ0.05). No systemic toxicity was observed in mice receiving rofecoxib. These data suggest that rofecoxib slows the growth of human pancreatic cancer through changes in gene expression that favor cell cycle arrest. Presented at the Forty-Third Annual Meeting of The Society for Surgery of the Alimentary Tract, San Francisco, California, May 19–22, 2002 (oral presentation).     

Androgen receptor-dependent regulation of Bcl-xL expression: Implication in prostate cancer progression

BACKGROUND: Recently we reported that silencing the androgen receptor (AR) gene reduced Bcl-xL expression that was associated with a profound apoptotic cell death in prostate cancer cells. In this study we further investigated AR-regulated Bcl-xL expression. METHODS: Prostate cancer cell line LNCaP and its sublines, LNCaP/PURO and LNCaP/Bclxl, were used for cell proliferation assay and xenograft experiments in nude mice. Luciferase gene reporters driven by mouse or human bcl-x gene promoter were used to determine androgen regulation of Bcl-xL expression. RT-PCR and Western blot assays were conducted to assess Bcl-xL gene expression. Chromatin immunoprecipitation assay was performed to determine AR interaction with Bcl-xL promoter. Bcl-xL-induced alteration of gene expression was examined using cDNA microarray assay. RESULTS: In cultured prostate cancer LNCaP cells, androgen treatment significantly increased Bcl-xL expression at mRNA and protein levels via an AR-dependent mechanism. Promoter analyses demonstrated that the AR mediated androgen-stimulated bcl-x promoter activation and that the AR interacted with bcl-x promoter. Enforced expression of Bcl-xL gene dramatically increased cell proliferation in vitro and promoted xenograft tumor growth in vivo. Genome-wide gene profiling analysis revealed that Bcl-xL expression was significantly higher in metastatic and castration-resistant diseases compared to normal prostate tissues or primary cancers. Bcl-xL overexpression significantly increased the expression of cyclin D2, which might be responsible for Bcl-xL-induced cell proliferation and tumor growth. CONCLUSIONS: Taken together, our data strongly suggest that androgen stimulates Bcl-xL expression via the AR and that increased Bcl-xL expression plays a versatile role in castration-resistant progression of prostate cancer.     

TGF-beta inhibits Akt-induced transformation in intestinal epithelial cells

BACKGROUND: During the early stages of colorectal carcinogenesis, the phosphatidylinositol 3-kinase (PI3K)/Akt pathway is activated, enabling the transformed cells to survive and grow in the absence of anchorage to extracellular matrix. Transforming growth factor beta (TGF-beta) is an important tumor suppressor in the colon, and it is inactivated during later stages of colorectal carcinogenesis. The purpose of this study was to determine whether TGF-beta inhibits Akt-induced anchorage-independent growth and resistance to anoikis in gut epithelial cells. METHODS: Rat intestinal epithelial cells (RIE-1) were infected with a retrovirus containing pLXSN-mAkt, and three independent clones were selected. Anchorage-independent growth was examined by colony formation in soft agar and cell counting in ultralow attachment plates. Anoikis was analyzed with the use of Annexin V staining. RESULTS: All three clones of RIE-1/mAkt formed colonies in soft agar, which were decreased by TGF-beta. TGF-beta induced anoikis and treatment with a general caspase inhibitor, zVAD-fluoromethyl ketone, blocked TGF-beta-mediated decrease in colony formation. CONCLUSIONS: TGF-beta attenuated Akt-induced anchorage-independent growth in RIE-1 cells in part by enhancing anoikis. Our data demonstrate a novel tumor-suppressor activity of TGF-beta and provide the molecular justification for the required activation of the PI3K/Akt pathway and the subsequent inactivation of TGF-beta signaling during colorectal carcinogenesis.     

Molecular determinants of susceptibility to oncolytic vesicular stomatitis virus in pancreatic adenocarcinoma

Background

M protein mutant vesicular stomatitis virus (M51R-VSV) has oncolytic properties against many cancers. However, some cancer cells are resistant to M51R-VSV. Herein, we evaluate the molecular determinants of vesicular stomatitis virus (VSV) resistance in pancreatic adenocarcinoma cells.

Methods

Cell viability and the effect of β-interferon (IFN) were analyzed using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay. Gene expression was evaluated via microarray analysis. Cell infectability was measured by flow cytometry. Xenografts were established in athymic nude mice and treated with intratumoral M51R-VSV.

Results

Four of five pancreatic cancer cell lines were sensitive to M51R-VSV, whereas Panc 03.27 cells remained resistant (81 ± 3% viability 72 h after single-cycle infection). Comparing sensitive MiaPaCa2 cells with resistant Panc 03.27 cells, significant differences in gene expression were found relating to IFN signaling (P = 2 × 10⁻⁵), viral entry (P = 3 × 10⁻⁴), and endocytosis (P = 7 × 10⁻⁴). MiaPaCa2 cells permitted high levels of VSV infection, whereas Panc 03.27 cells were capable of resisting VSV cell entry even at high multiplicities of infection. Extrinsic β-IFN overcame apparent defects in IFN-mediated pathways in MiaPaCa2 cells conferring VSV resistance. In contrast, β-IFN decreased cell viability in Panc 3.27 cells, suggesting intact antiviral mechanisms. VSV-treated xenografts exhibited reduced tumor growth relative to controls in both MiaPaCa2 (1423 ± 345% versus 164 ± 136%; P < 0.001) and Panc 3.27 (979 ± 153% versus 50 ± 56%; P = 0.002) tumors. Significant lymphocytic infiltration was seen in M51R-VSV–treated Panc 03.27 xenografts.

Conclusions

Inhibition of VSV endocytosis and intact IFN-mediated defenses are responsible for M51R-VSV resistance in pancreatic adenocarcinoma cells. M51R-VSV treatment appears to induce antitumor cellular immunity in vivo, which may expand its clinical efficacy.     

Ligand activation of alternatively spliced fibroblast growth factor receptor-1 modulates pancreatic adenocarcinoma cell malignancy

Pancreatic adenocarcinoma continues to be a devastating tumor (28,000 new cases per year in the United States; 10% 2-year survival). Pancreatic adenocarcinoma frequently (90% of the time) overexpresses fibroblast growth factor ligands (FGF-1 and FGF-2) and alternatively spliced high-affinity receptors (FGFR-lß) (FGFR-lct was previously found in normal pancreatic tissue). To study the significance of this observation in vitro, PANC-1 cells were stably transfected via the pMEXneo vector containing FGFR-la (PANC-la) or FGFR-lß (PANC-lß) isoforms. Cells were treated with 1 mg/ml of 5-fluorouracil. Cells were evaluated for growth inhibition, apoptosis (propidium iodide staining and flow cytometry, caspase 3 activation) and for Bcl-xL/BAX expression (by Western blot analysis). In vivo, 7 X 10⁶ cells of each isoform were injected into nude Balb/c mice for xenograft formation (N = 10). Compared to PANC-lß (9%) in vitro, 5-fluorouracil-induced death was significantly (P < 0.05) increased in PANC-la (20%) at 24 hours. Increased cell death in PANC-la was mediated by activated caspase 3 and was correlated with decreased expression of Bcl-xL/BAX. In vivo, PANC-lß readily demonstrated formation of tumor xenograft at 2 weeks, whereas PANC-la did not form tumors. Alternative splicing of FGFR-1 to the ß isoform appears to correlate with pancreatic adenocarcinoma cell growth in vivo and resistance to chemotherapy. Inhibition of FGFR-1 splicing or overexpression of FGFR-la inhibits pancreatic adenocarcinoma cell growth in vivo and restores cytotoxic responses to chemotherapy, thereby suggesting the basis of rational interventional strategies for this devastating tumor.     

Peptide YY augments gross inhibition by vitamin E succinate of human pancreatic cancer cell growth

BACKGROUND: Vitamin E succinate (VES) significantly inhibits cell growth in vitro in breast, prostate, and skin cancer cell lines. Our study demonstrated similar inhibitory effects on Mia PaCa-2 pancreatic cancer cells at the same concentration of VES (10 pg/ml). Peptide YY (PYY) also inhibits pancreatic cancer cell growth in vitro. We observed a significant additive effect on growth inhibition in Mia PaCa cells treated with both VES and PYY. METHODS: Human pancreatic ductal adenocarcinoma Mia PaCa-2 cells were cultured and treated once with either 10 pg/ml of VES or 500 pmols of PYY or with both agents together. The control group received an equivalent volume of solvents. MTT assay was performed at 24, 48, and 72 h to evaluate cell viability. RESULTS: Pancreatic cancer cell growth was reduced in all groups treated with PYY and VES. Student's t test was used to analyze the data for each treatment group. At 72 h, both PYY and vitamin E significantly inhibited cell growth compared to control. Combining the agents resulted in a dramatic additive inhibition of growth. CONCLUSION: PYY and vitamin E both inhibit growth of pancreatic cancer cells in vitro with a significant increase in effect when used in combination.     

胰腺癌细胞对5-Fu和吉西它滨获得性耐药后bcl-xL和mcl-1表达的变化

目的 :探讨胰腺癌细胞对 5 Fu和吉西它滨的获得性耐药后bcl xL 和mcl 1表达的变化。方法 :应用SRB方法检测 5 Fu和吉西它滨对胰腺癌细胞株Panc 1,Mia Paca 2和Capan 1的细胞毒性作用 ,应用Westernblot法来检测bcl xL 和mcl 1的蛋白表达水平。结果 :5 Fu和吉西它滨对 3株胰腺癌细胞均产生了细胞毒性作用 ,5 Fu长期作用后 ,Capan 1细胞IC50 上升了 2 .1倍 (P <0 .0 5 )。吉西它滨长期作用后 ,Capan 1细胞IC50 上升了 1.5倍 (P <0 .0 5 )。 5 Fu或吉西它滨长期作用后 ,产生了获得性耐药的胰腺癌细胞bcl xL 和mcl 1表达水平上调。结论 :5 Fu或吉西它滨长期作用后 ,产生了获得性耐药 ,这种耐药与bcl xL 和mcl 1的过度表达相关。     

丝裂原活化蛋白激酶磷酸酶1与胰腺癌细胞获得性耐药的关系

目的 探讨丝裂原活化蛋白激酶（MAPK）磷酸酶1（MKP-1）在介导胰腺癌耐药细胞株SWl990／Fu产生获得性耐药过程中的可能机制。方法 采用Northern印迹杂交和Western蛋白免疫印迹杂交方法,检测MKP-1在体外诱导建立的人胰腺癌耐药细胞株SWl990／Fu、亲本细胞株SWl990和胰腺癌细胞株MiaPaCa-2中的表达,分析MKP-1在SW1990／Fu产生获得性耐药前后的变化。结果 Northern印迹杂交结果显示,在SWl990／Fu、SWl990和MiaPaCa~细胞株中均检测到2400bp的MKP-1mRNA,MKP-1在SWl990／Fu的表达水平明显低于SWl990和MiaPaCa-2。在蛋白水平上,Western蛋白免疫印迹杂交结果也表明,与SWl990和MiaPaCa4相比,MKP-1蛋白在SWl990／Fu细胞中的表达水平明显降低。结论 MAPK家族的关键调节酶MKP-1可能参与SWl990／Fu获得性耐药的产生,推测细胞信号转导系统的改变可能是导致胰腺癌细胞产生获得性耐药的机制之一。     

组织因子途径抑制物2基因对Panc-1细胞裸鼠成瘤及转移的影响

目的观察组织因子途径抑制物2（TFPI-2）对胰腺癌细胞系Pane-1细胞裸鼠成瘤及转移的影响。方法将Pane-1-TFPI-2细胞接种到裸鼠皮下作为实验组，观察肿瘤生长情况并测量其大小；取皮下新生肿瘤组织进行原位胰腺接种，观察其对周围组织浸润及远处转移能力的影响。同时以Pane-1-V和Pane-1-P细胞作为对照组。结果实验组和对照组裸鼠皮下均成瘤，但实验组肿瘤体积小于对照组，分别为（438．0±69．8）、（852．0±102．9）和（831．0±78．1）mm’，差异有统计学意义（P〈0．05）。原位胰腺接种，对照组移植瘤浸润胰腺组织，有肝、肺、淋巴结及腹膜转移灶形成，免疫染色显示转移灶CEA阳性，证实其为胰腺肿瘤转移而来。实验组移植瘤包膜完整，无明显浸润及转移现象。结论TFPI-2能抑制肿瘤细胞生长、周围组织浸润及远处转移，为胰腺癌的基因治疗奠定了实验基础。     

Retrovirally mediated RNA interference targeting the M2 subunit of ribonucleotide reductase: A novel therapeutic strategy in pancreatic cancer

BACKGROUND: Ribonucleotide reductase M2 subunit (RRM2) overexpression enhances tumor chemoresistance and cellular invasiveness. We hypothesized that the RNA interference (RNAi) induced by retrovirally delivered small interfering RNA (siRNA) would sensitize pancreatic adenocarcinoma cells to gemcitabine and attenuate their invasive potential. METHODS: Stable suppression of RRM2 expression in PANC1, MIAPaCa2, BxPC3, and Capan2 cells was induced by exposure to a novel replication-deficient retrovirus, engineered to express RRM2-specific siRNA (psiRRM2), and confirmed by Western blot analysis. Single-base mismatch vector (psiControl) served as control. Ribonucleotide reductase activity was quantified, and gemcitabine 50% inhibitory concentrations were calculated. TUNEL staining and caspase profiling were performed after gemcitabine exposure. Cellular invasiveness was quantified in a Matrigel Boyden chamber. NF-kappaB activity and matrix metalloproteinase-9 (MMP-9) expression and activity were measured. RESULTS: RRM2 expression was stably and specifically suppressed in psiRRM2, but not psiControl transfectants. psiRRM2 transfectants exhibited lower 50% inhibitory concentrations, increased gemcitabine-induced apoptosis, and greater caspase-3 activation, relative to psiControl transfectants. Invasiveness was attenuated in psiRRM2 transfectants, as was NF-kappaB activity, MMP-9 expression, and MMP-9 activity, relative to psiControl transfectants. CONCLUSIONS: RRM2 gene silencing attenuates pancreatic adenocarcinoma cellular invasiveness and gemcitabine chemoresistance. Retroviral siRNA delivery can efficiently induce stable RNAi, allowing dissection of gene function and potentially representing a new therapeutic modality.     

组织因子、凝血酶受体和血栓调节蛋白在胰腺癌细胞中的表达

目的　研究组织因子 (TF)、凝血酶受体 (TR)和血栓调节蛋白 (TM )在胰腺癌细胞中的表达。方法　采用细胞培养、免疫细胞化学和Northern印迹分析方法。结果　每个抗原都在细胞膜及 (或 )细胞浆中有特征性的免疫反应 ,TF和TR主要在细胞浆 ,TM在细胞膜。TR表达越多 ,TM表达越少。TRmRNA在野生型胰腺癌细胞株中表达 ,凝血酶和水蛭素均降低TRmRNA的表达量。凝血酶可致人胰腺癌细胞株MiaPaCa 2和Panc 1DNA合成增加 (P <0 .0 5 ) ,在凝血酶刺激 0 .5和 6h时达高峰。结论　胰腺癌细胞的TF、TR和TM表达参与了胰腺癌的血液高凝状态。     

环状RNA-PCAC1促进胰腺导管腺癌侵袭转移的研究

目的探讨环状RNA（circRNA）-PCAC1在胰腺导管腺癌中的表达水平及其与患者临床病理特征、预后的关系。 方法鉴定circRNA-PCAC1，并通过功能实验观察其对胰腺导管腺癌侵袭转移能力的影响。采用RT-PCR检测76例胰腺导管腺癌组织与配对癌旁组织的circRNA-PCAC1表达水平，Cox回归模型和Kaplan-Meier曲线法分析circRNA-PCAC1与患者临床病理特征和预后的关系。 结果功能实验证实circRNA-PCAC1过表达显著促进胰腺导管腺癌侵袭转移能力。胰腺导管腺癌组织中circRNA-PCAC1的表达水平显著高于癌旁组织（P<0.01）。circRNA-PCAC1过表达与胰腺导管腺癌患者不良预后相关（P<0.05）。circRNA-PCAC1是胰腺导管腺癌患者总生存期（HR=1.733，95% CI：1.066~2.991，P=0.030）和无病生存期（HR=1.636，95% CI：1.090~2.811，P=0.042）的独立影响因素。 结论circRNA-PCAC1在胰腺导管腺癌中高表达并促进胰腺导管腺癌侵袭转移，提示其可能成为胰腺导管腺癌临床治疗的新靶点。     

Cell death under epithelial–mesenchymal transition control in prostate cancer therapeutic response

Prostate cancer is a widespread problem among men, with >160 000 new cases in 2017 alone. Androgen deprivation therapy is commonly used in prostate cancer treatment to block androgens required for cancer growth, but disease relapse after androgen deprivation therapy is both common and severe. Changes in androgen receptor signaling from androgen deprivation therapy have been linked to therapeutic resistance and tumor progression. Resistant cells can become reprogrammed to undergo epithelial–mesenchymal transition, a phenotypic switch from benign, epithelial cells to a mobile cell with mesenchymal traits. In these cells, attachment to their epithelial cell layer is no longer required for survival. Anoikis is a form of cell death that occurs when detachment from other cells and the basement membrane occurs. Epithelial cells have been shown to undergo epithelial–mesenchymal transition, avoid anoikis induction and progress to a metastatic phenotype. In prostate cancer progression to advanced disease, epithelial–mesenchymal transition induction (characterized by loss of epithelial cellular attachment protein E‐cadherin) correlates with a higher Gleason score, tumor progression, increased metastasis and higher biochemical recurrence. The concept of interfacing epithelial–mesenchymal transition with anoikis in the tumor microenvironment landscape will be discussed here, with focus on the significance of the functional exchange between the two processes in therapeutic targeting of advanced disease. The current evidence on the impact of loss of cell–cell contact, acquisition of chemoresistance, immune escape and metastatic spread in advanced tumors in response to transforming growth factor‐β on prostate cancer metastasis will be also discussed. The signaling cross‐talk between transforming growth factor‐β and androgen receptor signaling will be interrogated as a new therapeutic platform for the development of combination strategies to impair prostate cancer metastasis.