A universal multiple instance learning framework for whole slide image analysis.

BACKGROUND: The emergence of digital whole slide image (WSI) has driven the development of computational pathology. However, obtaining patch-level annotations is challenging and time-consuming due to the high resolution of WSI, which limits the applicability of fully supervised methods. We aim to address the challenges related to patch-level annotations. METHODS: We propose a universal framework for weakly supervised WSI analysis based on Multiple Instance Learning (MIL). To achieve effective aggregation of instance features, we design a feature aggregation module from multiple dimensions by considering feature distribution, instances correlation and instance-level evaluation. First, we implement instance-level standardization layer and deep projection unit to improve the separation of instances in the feature space. Then, a self-attention mechanism is employed to explore dependencies between instances. Additionally, an instance-level pseudo-label evaluation method is introduced to enhance the available information during the weak supervision process. Finally, a bag-level classifier is used to obtain preliminary WSI classification results. To achieve even more accurate WSI label predictions, we have designed a key instance selection module that strengthens the learning of local features for instances. Combining the results from both modules leads to an improvement in WSI prediction accuracy. RESULTS: Experiments conducted on Camelyon16, TCGA-NSCLC, SICAPv2, PANDA and classical MIL benchmark datasets demonstrate that our proposed method achieves a competitive performance compared to some recent methods, with maximum improvement of 14.6 % in terms of classification accuracy. CONCLUSION: Our method can improve the classification accuracy of whole slide images in a weakly supervised way, and more accurately detect lesion areas.

First Report of Fusarium pernambucanum Causing Fruit Rot of Melon in China.

In May of 2020, November of 2021 and May of 2022, a preharvest fruit rot with white mycelia was observed inside and outside of the fruits of thick skin muskmelon (Cucumis melo L.) growing in about ten greenhouses (each greenhouse had about 320 muskmelons) with disease incidence of 70% in Ningbo, Zhejiang Province of China. In order to identify the causal agent, plant tissues from the margin of the symptomatic tissue were sterilized for 1 min with 1% sodium hypochlorite (NaClO), 2 min with 75% ethyl alcohol, rinsed in sterile distilled water three times (Zhou et al 2019), and then placed on potato dextrose agar (PDA) plates containing streptomycin sulfate (100 µg/mL) at 25℃ for 4 days. Only Fusarium colonies were isolated from all the plant tissues. The growing hyphae were transferred to new PDA plates using the hyphal tip method, putative Fusarium colonies were purified by single-sporing. Six fungal isolates (Fi-1~6) were obtained. The average radial mycelial growth rate of Fusarium isolate Fi-3 was 4.6 mm/day at 25℃ in the dark on PDA, and like other five isolates. The colonies are abnormal, producing lots of aerial hyphae, each isolate was white to light orange. Isolate Fi-3 produced macroconidia with 4 to 6 septa, tapered with pronounced dorsiventral curvature and measured 21 to 30 µm long 4 to 5 µm wide on Spezieller Nährstoffarmer Agar (SNA) medium at 25℃ for 10 days (Leslie and Summerell 2006), but polyphialides and chlamydospores were still not available for 30 days. The pathogen species was further identified by translation elongation factor-1 alpha (EF-1α) sequencing. The EF-1α of six isolates were sequenced, and their EF-1α sequences were 100% identical to each other, and the sequence of strain Fi-3 was deposited in GenBank with accession no. OL782040 and was also compared with sequences in the FUSARIUM-ID database (Geiser et al. 2004), which indicated that it was 100% identical to those of F. pernambucanum strain NRRL 32864 (GenBank accession GQ505613), F. pernambucanum strain LC7040 (GenBank accession MK289626), and F. pernambucanum strain LC12149 (GenBank accession MK289588) within the Fusarium incarnatum - F. equiseti species complex 17 (FIESC17). Two phylogenetic trees were established based on the TEF1-α sequences of Fi-1~6 and other Fusarium spp., Fi-1~6 was clustered with the sequences of F. pernambucanum within the FIESC17. Thus, both morphological and molecular criteria supported identification of the strain as F. pernambucanum. A pathogenicity test was conducted to verify Koch's postulates, mycelium agar plugs (6 mm in diameter) were removed from the colony margin of a 3-day-old culture of strain Fi-3, healthy melon fruits were surface-sterilized with 70% ethanol and rinsed twice with sterile-distilled water. Then, the melons were wounded using a sterile inoculating needle to stab and inoculated by a mycelium agar plug of strain Fi-3 on the wound sites. 5 fruits were inoculated in each treatment, and a mycelium-free PDA plug was used as a negative control, repeated 3 times, at 25℃ with high relative humidity for 10 days. The results show disease symptoms similar to those naturally infected fruits on all inoculated melon fruits. The fungus re-isolated from the diseased fruits, showed the same colony morphology as the original isolate. Koch's postulates were repeated three times with the same results. Strain Fi-3 inoculated fruits without wounding remained healthy. To our knowledge, this is the first report of fruit rot of melon caused by F. pernambucanum in China.

Mechanisms of sunitinib resistance in renal cell carcinoma and associated opportunities for therapeutics.

Sunitinib is the first-line drug for renal cell carcinoma (RCC) treatment. However, patients who received sunitinib treatment will ultimately develop drug resistance after 6-15 months, creating a huge obstacle to the current treatment of renal cell carcinoma. Therefore, it is urgent to clarify the mechanisms of sunitinib resistance and develop new strategies to overcome it. In this review, the mechanisms of sunitinib resistance in renal cell carcinoma have been summarized based on five topics: activation of bypass or alternative pathway, inadequate drug accumulation, tumour microenvironment, metabolic reprogramming and epigenetic regulation. Furthermore, present and potential biomarkers, as well as potential treatment strategies for overcoming sunitinib resistance in renal cell carcinoma, are also covered.

Immunotherapy Strategy Targeting Programmed Cell Death Ligand 1 and CD73 with Macrophage-Derived Mimetic Nanovesicles to Treat Bladder Cancer.

Combination immunotherapy is a promising strategy to remove the inhibitory effect of the tumor microenvironment on immune effector cells, improving the efficacy of immune checkpoint inhibitor treatment in bladder cancer. However, it is challenging to deliver multiple drugs to the tumor tissue effectively and simultaneously to ensure optimal therapeutic effects. Macrophage-derived exosome-mimetic nanovesicles (EMVs) were designed and validated as a nanoplatform for coloading and delivery of the CD73 inhibitor (AB680) and the monoclonal antibody to programmed cell death ligand 1 (aPDL1). The tumor-targeting, biosafety, and therapeutic effects of these nanocomplexes (AB680@EMVs-aPDL1), as a combined immunotherapy strategy for bladder cancer, were assessed in vitro and in vivo. Our results indicate that the nanodrug system was highly stable, provided adequate biosafety, and enhanced tumor targeting in a mouse model of bladder cancer. Moreover, the CD73 inhibitor reduced extracellular adenosine production, and the combination therapy significantly promoted the activation and infiltration of cytotoxic T-lymphocytes, which helped to optimally suppress tumor growth and extend median survival in vivo. Therefore, using EMVs to deliver a combination of aPDL1 and the CD73 inhibitor may be a useful combined immunotherapy strategy for treating bladder cancer.

The Clinical Implications and Molecular Mechanism of CX3CL1 Expression in Urothelial Bladder Cancer.

BACKGROUND: CX3CL1 is a chemokine that may play important roles in cancer immune regulation. Its mechanism in bladder cancer (BCa) is poorly understood. The objective of the current study was to evaluate the association between CX3CL1 and BCa and the related biological mechanisms. METHODS: A total of 277 patients with BCa were enrolled in the present study. The association between CX3CL1 expression and disease outcome was evaluated. In vitro and in vivo experiments were performed using the TCCSUP cell line to investigate the function of CX3CL1 in BCa. RESULTS: Compared with low expression, high expression of CX3CL1 was significantly associated with poorer progression-free survival (hazard ratio [HR]=2.03, 95% confidence interval [95% CI]: 1.26-3.27, P=0.006), cancer-specific survival (HR=2.16, 95% CI: 1.59-2.93, P<0.001), and overall survival (HR=1.55, 95% CI: 1.08-2.24, P=0.039). Multivariable Cox regression analysis suggested that CX3CL1 was an independent prognostic factor for BCa outcomes. In vitro and in vivo experiments indicated that high expression of CX3CL1 was significantly associated with cell proliferation (P<0.001) and invasion (P<0.001). Gene expression profiling results showed that after CX3CL1 knockdown, CDH1 was significantly upregulated, while ETS1, RAF1, and EIF4E were significantly downregulated. Pathway enrichment analysis suggested that the ERK/MAPK signaling pathway was significantly inhibited (P<0.001). CONCLUSIONS: CX3CL1 is an independent predictor of a poor prognosis in BCa and can promote the proliferation and invasion of BCa cells.

Depression Induced by CUMS Leads to Bladder Cancer Development and Local Tumor Immunosuppression in Mice.

Depression is a common mental disease in bladder cancer patients, leading to a loss of happiness, an increase in the suicide rate, and higher mortality. However, the influence of depression on bladder tumor tissue remains unknown. In this current study, a subcutaneous bladder cancer xenograft model was established on male C57 mice with mouse bladder cell line MB49. Chronic unpredictable mild stress (CUMS) was established to simulate depression in bladder cancer patients. The depression caused by CUMS was confirmed by testing sucrose preference and plasma cortisol and adrenocorticotropic hormone (ACTH) levels. Then, we measured and weighed tumors to demonstrate the promotion of tumor growth by CUMS. Immune-related cells and molecules were examined to reveal the mechanism. There is a significant decrease of CD8+/CD4+T cells ratio, NK cells, IL-2, and IFN-γ and a significant increase of T regs, IL-6, IL-1ß, TNF-α, IL-10, and PGE2 in CUMS group, indicating the inhibition of immunity in the tumor microenvironment. Our results supported the perspective that depression exacerbated bladder cancer and revealed a possible mechanism. We suggest attaching importance to the psychological health of bladder cancer patients to prevent a worse prognosis induced by depression.

Increased Risk of Recurrence of Non-Muscle Invasive Bladder Cancer Associated With Psychological Distress: A Prospective Cohort Study.

OBJECTIVE: The primary aim was to evaluate the influence of depressive and anxiety symptoms on the 1-year recurrence rate of non-muscle invasive bladder cancer (NMIBC) patients. The secondary aim was to examine the risk factors leading to psychological distress. METHODS: A total of 104 NMIBC patients were enrolled for interviews, and the Hospital Anxiety and Depression Scale (HADS) questionnaire survey was administered 1 month after their operation. Their cystoscopy results were followed up. The risk factors affecting their 1-year recurrence rate were evaluated through univariate analysis, Cox regression and Kaplan-Meier analysis. The risk factors causing depressive and anxiety symptoms were evaluated through univariate analysis and logistic regression. RESULTS: In addition to American Urological Association risk stratification, depressive symptoms were another independent risk factor for recurrence in NMIBC patients (HR: 2.493, 95% CI: 1.048-5.930, p=0.039), and the increase in the recurrence rate was highly significant in intermediate-risk patients (HR: 8.496, 95% CI: 2.178-33.138, p=0.019). Anxiety symptoms were not an independent risk factor for recurrence (HR: 1.655, 95% CI: 0.714-3.837, p=0.240). We also observed that the burden of medical expenses of NMIBC on the family was an independent risk factor for depressive symptoms (p=0.029) and anxiety symptoms (p=0.048); chronic pain was an independent risk factor for anxiety symptoms (OR: 3.447, 95% CI: 1.182-10.052, p=0.023). CONCLUSION: Depression symptoms are an independent risk factor for recurrence in NMIBC patients. Moreover, the burden of medical expenses on the family is an independent risk factor for depressive and anxiety symptoms in NMIBC patients. Additionally, chronic pain is a risk factor for anxiety symptoms in NMIBC patients. This study provided a theoretical foundation for clinical oncologists to pay more attention to the mental health of NMIBC patients.

Chronic Psychological Stress Attenuates the Efficacy of anti-PD-L1 Immunotherapy for Bladder Cancer in Immunocompetent Mice.

We aimed to explore whether chronic psychological stress affects the efficacy of immune checkpoint inhibitors (ICIs) immunotherapy in bladder cancer. The chronic unpredictable mild stress (CUMS) process was applied during the administration of anti-PD-L1 for subcutaneous tumors in mice. Tumor regression was obviously shown in anti-PD-L1 therapy groups, while this effect was notably attenuated by CUMS. Additionally, increased infiltration of regulatory T-cells, decreased amount of CD8+ lymphocytes, and reduced levels of tumor-associated cytokines in tumor sites were observed in mice treated with anti-PD-L1 under CUMS. Therefore, chronic psychological stress could weaken the potency of anti-PD-L1 immunotherapy for bladder cancer.

Mechanisms of enzalutamide resistance in castration-resistant prostate cancer and therapeutic strategies to overcome it.

Prostate cancer is the second most common malignancy in men and androgen deprivation therapy is the first-line therapy. However, most cases will eventually develop castration-resistant prostate cancer after androgen deprivation therapy treatment. Enzalutamide is a second-generation androgen receptor antagonist approved by the Food and Drug Administration to treat patients with castration-resistant prostate cancer. Unfortunately, patients receiving enzalutamide treatment will ultimately develop resistance via various complicated mechanisms. This review examines the emerging information on these resistance mechanisms, including androgen receptor-related signalling pathways, glucocorticoid receptor-related pathways and metabolic effects. Notably, lineage plasticity and phenotype switching, gene polymorphisms and the relationship between microRNAs and drug resistance are addressed. Furthermore, potential therapeutic strategies for enzalutamide-resistant castration-resistant prostate cancer treatment are suggested, which can help discover more effective and specific regimens to overcome enzalutamide resistance.

Chronic Unpredictable Mild Stress Accelerates the Growth of Bladder Cancer in a Xenograft Mouse Model.

OBJECTIVE: Chronic psychological stress is common in patients with bladder cancer. An increasing number of evidence demonstrated that psychiatric disorder leads to worse prognostic outcomes in bladder cancer. This study was to investigate the effects of chronic psychological stress on the growth of bladder cancer and its potential mechanisms. METHODS: A xenograft mouse model was established by subcutaneously implanting the human bladder cancer cell line T24 into nude mice. All of the tumor-bearing mice (N=20) were randomly separated into two groups. Mice in the control group were subjected to normal feeding conditions, while in another group, a chronic unpredictable mild stress (CUMS) model was established, in which mice were exposed to various types of stressors. Various analyses were performed on parameters including the tumor volume, tumor weight, expression of Caspase-3 and VEGF, proportion of Ki-67 positive cells (Ki-67 index), microvessel density (MVD) and serum concentrations of epinephrine and cortisol. RESULTS: In the CUMS group, the growth of transplanted tumors was distinctly accelerated, with the weight of removed tumors at the end of experiment increased by 34.07% compared to that of the control. Serum levels of epinephrine and cortisol determined by ELISA were significantly increased by CUMS. Immunohistochemistry and Western blot analysis showed that the expression of Caspase-3 was downregulated, whereas the expression of VEGF was upregulated in the CUMS group. Meanwhile, CUMS could increase the Ki-67 index and MVD. CONCLUSION: Our research supports the hypothesis that CUMS could affect the growth of bladder cancer in nude mice, indicating that the intervention of chronic psychological stress may be a possible therapeutic strategy for bladder cancer.

SREBP1 siRNA enhance the docetaxel effect based on a bone-cancer dual-targeting biomimetic nanosystem against bone metastatic castration-resistant prostate cancer.

Until recently, there have been limited options for patients with bone metastatic castration-resistant prostate cancer (BmCRPC) following the failure of or development of resistance to docetaxel (DTX), which is one of the frontline treatments. Sterol regulatory element-binding protein 1 (SREBP1) is reported to regulate abnormal lipid metabolism and to promote the progression and metastasis of prostate cancer (PCa). The siRNA interferes SREBP1 may provide an efficient treatment when combined with DTX. Methods: In this study, lipoic acid (LA) and cross-linked peptide-lipoic acid micelles were cross-linked (LC) for DTX and siSREBP1 delivery (LC/D/siR). Then, cell membrane of PCa cells (Pm) and bone marrow mesenchymal stem cells (Bm) were fused for cloaking LC/D/siR (PB@LC/D/siR). Finally, the synthesized PB@LC/D/siR was evaluated in vitro and in vivo. Results: PB@LC/D/siR is internalized in PCa cells by a mechanism of lysosome escape. Tumor targeting and bone homing studies are evaluated using bone metastatic CRPC (BmCRPC) models, both in vitro and in vivo. Moreover, the enhanced anti-proliferation, anti-migration and anti-invasion capacities of DTX- and siSREBP1- loaded PB@LC (PB@LC/D/siR) were observed in vitro. Furthermore, PB@LC/D/siR was able to suppress the growth of the tumor effectively with deep tumor penetration, high safety and good protection of the bone at the tumor site. Additionally, the mRNA levels and protein levels of SREBP1 and SCD1 were able to be significantly downregulated by PB@LC/D/siR. Conclusion: This study presented a bone-cancer dual-targeting biomimetic nanodelivery system for bone metastatic CRPC.

Association between three genetic variants in kallikrein 3 and prostate cancer risk.

BACKGROUND: Epidemiological studies have assessed the association between kallikrein 3 (KLK3) polymorphisms and prostate cancer (PCa) susceptibility. However, published data on this association are somewhat inconclusive. METHODS: Articles investigating the association between three KLK3 (rs1058205, rs2735839, and rs266882) variants and PCa susceptibility were searched from online databases, which included 35,838 patients and 36,369 control participants. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to demonstrate the strength of the association. We also utilized ELISA to detect serum expression of KLK3. In addition, in silico tools were adopted to evaluate the relationship of KLK3 expression and PCa survival time. RESULTS: The overall results indicated that polymorphism T>C of rs1058205 was associated with decreased risk of PCa (allele contrast: OR = 0.75, 95% CI = 0.64-0.88, Pheterogeneity < 0.001; homozygote comparison: OR = 0.58, 95% CI = 0.42-0.81, Pheterogeneity < 0.001), particularly in Caucasian population (allele contrast: OR = 0.77, 95% CI = 0.65-0.91, Pheterogeneity < 0.001; homozygote comparison: OR = 0.58, 95% CI = 0.41-0.82, Pheterogeneity < 0.001). No association was observed between the polymorphism A>G of rs2735839 and risk of PCa. In addition, no association was observed between polymorphism A>G of rs266882 and risk of PCa. Serum KLK3 levels in PCa patients carrying CC/CT genotypes were statistically lower than those carrying TT genotypes. Conclusion: This meta-analysis suggests that rs1058205 polymorphism of KLK3 is a risk factor for PCa development, polymorphism T>C of rs1058205 is associated with decreased susceptibility to PCa particularly in Caucasian population.

EORTC risk tables are more suitable for Chinese patients with nonmuscle-invasive bladder cancer than AUA risk stratification.

BACKGROUND: Patients with non-muscle-invasive bladder cancer (NMIBC) need accurate estimations of the risk of recurrence and progression. Physicians can offer individualized therapy after identifying high-risk tumors. In our study, we compared the applicability of European Organization for Research and Treatment of Cancer (EORTC) risk tables and American Urological Association (AUA) risk stratification in Chinese patients with NMIBC. METHODS: We retrospectively studied 301 patients with NMIBC who underwent transurethral resection of bladder tumor (TURBT) between October 2000 and July 2009 at Huashan Hospital of Fudan University and analyzed their parameters. The recurrence and progression rates at 1 and 5 years postoperatively were calculated along with 95% confidence intervals. We compared them with results obtained from the EORTC risk tables and AUA risk stratification. P values <.05 were considered statistically significant. RESULTS: The median patient age was 67 years (21-92 years) and the median follow-up duration was 46 months (2-151 months). We used EORTC risk tables to classify patients into 3 groups, depending on whether they suffered recurrence or progression after TURBT. Kaplan-Meier curves showed significant differences among the 3 recurrence-free survival (RFS) levels (P < .0001, log-rank test) and among the 3 progression-free survival (PFS) levels (P < .0001, log-rank test). AUA risk stratification showed the same results. Both classifications were suitable to predict recurrence and progression in Chinese patients. However, for high-risk patients in both series, Kaplan-Meier curves showed significant differences between RFS levels (P < .0001, log-rank test) and between PFS levels (P < .0001, log-rank test). EORTC risk tables were stricter and AUA was more sensitive in assigning patients to a high-risk group. CONCLUSION: EORTC risk tables are better than AUA risk stratification for predicting recurrence and progression in Chinese patients with NMIBC, especially among high-risk patients.

NOS3 895G>T and CBR3 730G>A Are Associated with Recurrence Risk in Non-Muscle-Invasive Bladder Cancer with Intravesical Instillations of THP.

OBJECTIVES: To analyze the correlation between pharmacogenomic biomarkers and the efficacy of pirarubicin (THP, also named 4'-O-tetrahydropyranyl-adriamycin) and to explore potential associations of individual genetic backgrounds with the clinical outcomes of non-muscle-invasive bladder cancer (NMIBC) patients. METHODS: Between July 2003 and June 2011, a total of 91 patients were treated with transurethral resection (TUR) of the bladder tumor and were histopathologically confirmed to have NMIBC. Patients received an immediate instillation and maintenance therapy with THP. All patients underwent follow-up for recurrence. We genotyped 13 single nucleotide polymorphisms (SNPs) from blood and saliva DNA samples of all patients. RESULTS: The associations of patients' genotypes with tumor recurrence risks were analyzed by survival analysis. A total of 16 (17.6%) of the 91 patients with NMIBC had tumor recurrences with a median follow-up of 17 months (range, 2-83 months). We confirmed the effect of the European Organization for Research and Treatment of Cancer (EORTC) risk score for predicting tumor recurrence (p = 0.002, log-rank test). We adjusted for the EORTC score and found that 2 SNPs, NOS3 895G>T (rs1799983) (p = 0.02, HR = 4.32, 95% CI, 1.30-14.39, GT+TT vs. GG) and CBR3 730G>A (rs1056892) (p = 0.04, HR = 2.57, 95% CI, 1.07-6.18, GA+AA vs. GG), were significantly associated with a higher recurrence risk after TUR and instillations of THP in NMIBC patients. CONCLUSIONS: Our results suggest that NOS3 895G>T and CBR3 730G>A are genetic markers that can be used to predict tumor recurrence in NMIBC patients receiving intravesical instillations of THP. The effects of those 2 SNPs are independent of the EORTC scores. Further studies with larger sample sizes and longer follow-ups are needed to confirm our results.

A Cumulative Analysis of Current Evidence for Association between Expression of Epithelial-Mesenchymal Transition Markers and Clinicopathological Outcomes in Patients after Radical Prostatectomy.

BACKGROUND: Epithelial-mesenchymal transition (EMT) was reported to have an important effect on malignant metastasis; however, it remained largely unknown if EMT marker expression of neoplastic tissue had predictive value for prognosis of prostate cancer. METHODS: We searched for published studies which measured EMT marker expression and analyzed its association with clinical outcomes of patients after Radical Prostatectomy (RP). We reviewed and pooled-analyzed the association of EMT marker expression and biochemical recurrence-free survival (BFS), as well as the difference in strong or weak expression of EMT markers in tumors of high Gleason score (≥8). RESULTS: A total of 25 studies with 14 EMT markers were included for review and meta-analysis. Only mesenchymal markers of N-cadherin, snail, twist, vimentin, and slug seemed to be significantly associated with decreased BFS in strongly expressed patients. Weak expression of epithelial markers (E-cadherin and α-catenin) and strong expression of mesenchymal markers (N-cadherin, snail, twist, and vimentin) seemed to be more frequent in tumors of Gleason ≥8. CONCLUSION: Strong expression of mesenchymal markers (N-cadherin, snail, twist, and vimentin) seemed to have significant predictive value for decreased BFS in patients after RP.

Coatomer subunit beta 2 (COPB2), identified by label-free quantitative proteomics, regulates cell proliferation and apoptosis in human prostate carcinoma cells.

Label-free quantitative proteomics has broad applications in the identification of differentially expressed proteins. Here, we applied this method to identify differentially expressed proteins (such as coatomer subunit beta 2 [COPB2]) and evaluated the functions and molecular mechanisms of these proteins in prostate cancer (PCA) cell proliferation. Proteins extracted from surgically resected PCA tissues and adjacent tissues of 3 patients were analyzed by label-free quantitative proteomics. The target protein was confirmed by bioinformatics and GEO dataset analyses. To investigate the role of the target protein in PCA, we used lentivirus-mediated small-interfering RNA (siRNA) to knockdown protein expression in the prostate carcinoma cell line, CWR22RV1 cells and assessed gene and protein expression by reverse transcription quantitative polymerase chain reaction and western blotting. CCK8 and colony formation assays were conducted to evaluate cell proliferation. Cell cycle distributions and apoptosis were assayed by flow cytometry. We selected the differentiation-related protein COPB2 as our target protein based on the results of label-free quantitative proteomics. High expression of COPB2 was found in PCA tissue and was related to poor overall survival based on a public dataset. Cell proliferation was significantly inhibited in COPB2-knockdown CWR22RV1 cells, as demonstrated by CCK8 and colony formation assays. Additionally, the apoptosis rate and percentage of cells in the G1 phase were increased in COPB2-knockdown cells compared with those in control cells. CDK2, CDK4, and cyclin D1 were downregulated, whereas p21 Waf1/Cip1 and p27 Kip1 were upregulated, affecting the cell cycle signaling pathway. COPB2 significantly promoted CWR22RV1 cell proliferation through the cell cycle signaling pathway. Thus, silencing of COPB2 may have therapeutic applications in PCA.

COPB2 Is Upregulated in Prostate Cancer and Regulates PC-3 Cell Proliferation, Cell Cycle, and Apoptosis.

BACKGROUND AND AIMS: Transport of membranes and proteins in eukaryotic cells is mediated by vesicular carriers. Coatomer complex I (COPI)-coated vesicles are involved in the transport between endoplasmic reticulum (ER) and Golgi complex. Several studies indicated that some subunits of COPI were correlated with the cell proliferation of malignant tumors. The present study focused on the function of coatomer protein complex subunit ß 2 (COPB2), one of seven proteins in COPI, in prostate cancer (PCa). METHODS: COPB2 gene expression was first analyzed by immunohistochemistry (IHC) in 15 paired PCa and carcinoma adjacent normal tissue from patients. To investigate the role of COPB2 in PCa, we used lentivirus-mediated small interfering RNA (siRNA) to knockdown COPB2 expression in human PCa cell line PC-3 and assessed it by RT-qPCR. Cellomics ArrayScan VTI imaging and colony formation were conducted to evaluate cell proliferation. Cell cycle phase arrest and apoptosis were assayed by flow cytometry. RESULTS: COPB2 gene was upregulated in the PCa tissue. Cell proliferation was significantly inhibited in COPB2-silenced PC-3 cells using both Cellomics ArrayScan VTI imaging and colony formation assays. S-phase cell counts were significantly decreased; G1- and G2-phase cell counts were significantly increased in COPB2-siRNA group than the control group. Apoptosis was significantly increased in COPB2-siRNA cells. CONCLUSIONS: COPB2 significantly promoted PC-3 cell proliferation and colony formation through the cell cycle and apoptosis pathway. Moreover, COPB2 showed a clinical correlation and may serve as a biomarker for the detection for PCa.

Periostin Mediates TGF-ß-Induced Epithelial Mesenchymal Transition in Prostate Cancer Cells.

BACKGROUND: In our previous study, we found that periostin was upregulated in prostate cancer, and its expression could be modulated by TGF-ß. TGF-ß could upregulate periostin expression in some cells, and both TGF-ß and periostin could induce epithelial mesenchymal transition (EMT). We aimed to study the effect of periostin in the process of TGF-ß-induced EMT in prostate cancer cells. METHODS: We constructed a lentivirus vector containing the periostin gene and transduced it into PC3 and DU145 cells. After confirming periostin overexpression by PCR and Western blotting, we used an MTT assay to establish a growth curve to measure cell proliferation. Additionally, we performed transwell and wound healing assays to measure cell invasion and migration, respectively. Lastly, we measured the expression of EMT associated factors using Western blot analysis to test the effect of periostin on EMT in prostate cancer cells. RESULTS: PCR and Western blot analyses confirmed that periostin was upregulated after infection with the periostin lentiviral vector. Periostin overexpression promoted increased cell proliferation, invasion, and migration as measured by MTT, transwell, and wound healing assays, respectively. Western blot analysis illustrated that periostin overexpression increased the expression of EMT associated factors, and periostin overexpression activated Akt and GSK-3ß, which could be inhibited using a PI3K inhibitor. Additionally, TGF-ß increased the levels of STAT3, Twist1 and periostin, while both STAT3 shRNA and Twist1 shRNA inhibited periostin expression. However, STAT3 shRNA also decreased Twist1 expression. Although reduction of STAT3, Twist1 or periostin levels with shRNA inhibited TGF-ß-induced overexpression of EMT associated factors, periostin overexpression could reverse such inhibition by interfering with STAT3 and Twist1. Similarly, periostin overexpression also reversed inhibition of cell invasion induced by interference of STAT3 and Twist1. CONCLUSION: Our findings indicate that periostin is an important mediator of TGF-ß-induced EMT and suggest that periostin is a potential therapeutic target for suppressing the metastatic progression of prostate cancer.

Human epidermal growth factor receptor 2: a significant indicator for predicting progression in non-muscle-invasive bladder cancer especially in high-risk groups.

PURPOSE: Current pathological and clinical parameters provide important prognostic information. However, they are still limitations for predicting the true malignant potential of a specific cancer. The aim of this study was to validate the predicting role of HER-2 expression and demonstrated that combination of the high-risk factors with HER-2 expression is more valuable for determining which non-muscle-invasive bladder cancer (NMIBC) is more aggressive. MATERIALS AND METHODS: In total, 238 patients treated by transurethral resection of the bladder tumor were histopathologically confirmed to be NMIBC. Two experienced uropathologists re-reviewed the slides. HER-2 expression was evaluated by immunohistochemistry and scored for intensity and area of staining. The association of HER-2 staining with tumor recurrence and progression was evaluated by univariate and multivariate analyses and Kaplan-Meier survival curves. RESULTS: In multivariable analyses, HER-2 expression was an independent risk factor for predicting tumor progression (HR 2.64, p = 0.024). Combining the EORTC risk scores with HER-2 expression status led to more accurate prediction of progression, especially in patients with intermediate- and high-risk EORTC scores (p < 0.0001, log-rank test). CONCLUSIONS: HER-2 positivity is prognostic for predicting progression to muscle invasion in NMIBC. Combination of the high-risk factors with HER-2 expression is more valuable for determining which NMIBC is more aggressive.

Snail is an independent prognostic indicator for predicting recurrence and progression in non-muscle-invasive bladder cancer.

OBJECTIVE: Snail, an inducer of the epithelial-to-mesenchymal transition, increases motility and invasiveness of cancer cells by repressing E-cadherin expression. We investigate the relationship between Snail expression and clinicopathological parameters and evaluate its prognostic significance in patients with non-muscle-invasive bladder cancer (NMIBC). MATERIALS AND METHODS: A total of 332 patients treated with transurethral resection of the bladder tumor between October 2002 and July 2010 were histopathologically confirmed to be NMIBC. Tumor recurrence and progression were followed up in all patients. Immunohistochemical staining of 332 slices was performed. The expression of Snail was evaluated by ICH and graded for intensity and area of staining. We correlated Snail scores with clinical and pathological variables, and association of Snail staining with tumor recurrence and progression was evaluated by univariate, multivariate analysis and Kaplan-Meier survival curves. RESULTS: Of 332 patients with NMIBC, there was Snail positivity in 104 tumors (31.3 %), and Snail expression correlated with age, multifocality, carcinoma in situ, tumor stage and tumor grade (each p < 0.05, respectively). A multivariate Cox regression model revealed that Snail expression was an independent predictor of tumor recurrence [hazard ratio (HR) 1.95, p = 0.001] and progression (HR 2.34, p = 0.014) in patients with NMIBC. Kaplan-Meier estimates showed that Snail expression was significantly associated with recurrence and progression (log-rank test, p < 0.0001, respectively). CONCLUSIONS: Analysis of Snail expression in 332 NMIBC tissue specimens revealed its potential usefulness as a biomarker to predict the NMIBC prognosis.