Epithelial plasticity, cancer stem cells, and the tumor-supportive stroma in bladder carcinoma

Integrating the PD-L1 Prognostic Biomarker in Non-Muscle Invasive Bladder Cancer in Clinical Practice-A Comprehensive Review on State-of-the-Art Advances and Critical Issues

Bladder cancer (BC) is one of the most prevalent cancers worldwide. Non-muscle invasive bladder cancer (NMIBC), comprising the majority of initial BC presentations, requires accurate risk stratification for optimal management. This review explores the evolving role of programmed cell death ligand 1 (PD-L1) as a prognostic biomarker in NMIBC, with a particular focus on its implications in the context of Bacillus Calmette-Guérin (BCG) immunotherapy. The literature suggests a potential association between elevated PD-L1 status and adverse outcomes, resistance to BCG treatment, and disease progression. However, conflicting findings and methodological issues highlight the heterogeneity of PD-L1 assessment in NMIBC, probably due to the complex biological mechanisms that regulate the interaction between PD-L1 and the tumor microenvironment. The identification of PD-L1 as a prognostic biomarker provides ground for tailored therapeutic interventions, including immune checkpoint inhibitors (ICIs). Nevertheless, challenges such as intratumoral heterogeneity and technical issues underscore the need for standardized protocols and larger, homogeneous trials. This review contributes to the ongoing debate on the personalized management of NMIBC patients, focusing on the advances and perspectives of incorporating PD-L1 as a biomarker in this setting.

CD276-dependent efferocytosis by tumor-associated macrophages promotes immune evasion in bladder cancer

Interplay between innate and adaptive immune cells is important for the antitumor immune response. However, the tumor microenvironment may turn immune suppressive, and tumor associated macrophages are playing a role in this transition. Here, we show that CD276, expressed on tumor-associated macrophages (TAM), play a role in diminishing the immune response against tumors. Using a model of tumors induced by N-butyl-N-(4-hydroxybutyl) nitrosamine in BLCA male mice we show that genetic ablation of CD276 in TAMs blocks efferocytosis and enhances the expression of the major histocompatibility complex class II (MHCII) of TAMs. This in turn increases CD4 + and cytotoxic CD8 + T cell infiltration of the tumor. Combined single cell RNA sequencing and functional experiments reveal that CD276 activates the lysosomal signaling pathway and the transcription factor JUN to regulate the expression of AXL and MerTK, resulting in enhanced efferocytosis in TAMs. Proving the principle, we show that simultaneous blockade of CD276 and PD-1 restrain tumor growth better than any of the components as a single intervention. Taken together, our study supports a role for CD276 in efferocytosis by TAMs, which is potentially targetable for combination immune therapy.

LASS2 enhances chemosensitivity to cisplatin by inhibiting PP2A-mediated β-catenin dephosphorylation in a subset of stem-like bladder cancer cells

BACKGROUND

The benefits of first-line, cisplatin-based chemotherapy for muscle-invasive bladder cancer are limited due to intrinsic or acquired resistance to cisplatin. Increasing evidence has revealed the implication of cancer stem cells in the development of chemoresistance. However, the underlying molecular mechanisms remain to be elucidated. This study investigates the role of LASS2, a ceramide synthase, in regulating Wnt/β-catenin signaling in a subset of stem-like bladder cancer cells and explores strategies to sensitize bladder cancer to cisplatin treatment.

METHODS

Data from cohorts of our center and published datasets were used to evaluate the clinical characteristics of LASS2. Flow cytometry was used to sort and analyze bladder cancer stem cells (BCSCs). Tumor sphere formation, soft agar colony formation assay, EdU assay, apoptosis analysis, cell viability, and cisplatin sensitivity assay were used to investigate the functional roles of LASS2. Immunofluorescence, immunoblotting, coimmunoprecipitation, LC-MS, PCR array, luciferase reporter assays, pathway reporter array, chromatin immunoprecipitation, gain-of-function, and loss-of-function approaches were used to investigate the underlying mechanisms. Cell- and patient-derived xenograft models were used to investigate the effect of LASS2 overexpression and a combination of XAV939 on cisplatin sensitization and tumor growth.

RESULTS

Patients with low expression of LASS2 have a poorer response to cisplatin-based chemotherapy. Loss of LASS2 confers a stem-like phenotype and contributes to cisplatin resistance. Overexpression of LASS2 results in inhibition of self-renewal ability of BCSCs and increased their sensitivity to cisplatin. Mechanistically, LASS2 inhibits PP2A activity and dissociates PP2A from β-catenin, preventing the dephosphorylation of β-catenin and leading to the accumulation of cytosolic phospho-β-catenin, which decreases the transcription of the downstream genes ABCC2 and CD44 in BCSCs. Overexpression of LASS2 combined with a tankyrase inhibitor (XAV939) synergistically inhibits tumor growth and restores cisplatin sensitivity.

CONCLUSIONS

Targeting the LASS2 and β-catenin pathways may be an effective strategy to overcome cisplatin resistance and inhibit tumor growth in bladder cancer patients.

Anticancer effects of cell-free culture supernatant of Escherichia coli in bladder cancer cell line: New insight into the regulation of inflammation

Bladder cancer (BC) is the 10th most common malignancy in worldwide, with substantial mortality and morbidity if not treated effectively. According to various research, inflammatory circumstances majorly impact the microenvironment of bladder cancer, and the chronic presence of cytokines and chemokines promotes tumor progression. In this investigation, we explored the impact of cell-free culture supernatant ofEscherichia colistrain 536 on inflammatory cytokines and chemokines in bladder cancer model microarray data (GSE162251). Then we examined in silico outcomes on human bladder cancer cell line 5637 to verify and extrapolate findings. This investigation revealed for the first time that this compound has potent suppressor effects on interleukin 1 beta (IL-1β), C-C motif chemokine ligand 2 (CCL2), and C-X3-C motif chemokine ligand 1 (CX3CL1) gene expression as well as increased NAD(P)H quinone dehydrogenase 1 (NQO1), as an anti-oxidant agent, gene expression in 4, 8, and 24 h. Moreover, we confirmed that c-MYC, a member of the MYC proto-oncogene family, gene expression reduced in 5637 cells in 4 h and then followed up its expression in 8 and 24 h. In addition, our investigation demonstrated that the supernatant raised the BCL2-Associated X Protein/B-cell lymphoma 2 (BAX/BCL2) ratio, and subsequent flow cytometry analysis demonstrated that the supernatant induction apoptosis and necrosis. In conclusion, our findings demonstrate that this compound is a potential candidate for the suppression of bladder cancer progression.

miRNA/epithelial-mesenchymal axis (EMT) axis as a key player in cancer progression and metastasis: A focus on gastric and bladder cancers

The metastasis a major hallmark of tumors that its significant is not only related to the basic research, but clinical investigations have revealed that majority of cancer deaths are due to the metastasis. The metastasis of tumor cells is significantly increased due to EMT mechanism and therefore, inhibition of EMT can reduce biological behaviors of tumor cells and improve the survival rate of patients. One of the gaps related to cancer metastasis is lack of specific focus on the EMT regulation in certain types of tumor cells. The gastric and bladder cancers are considered as two main reasons of death among patients in clinical level. Herein, the role of EMT in regulation of their progression is evaluated with a focus on the function of miRNAs. The inhibition/induction of EMT in these cancers and their ability in modulation of EMT-related factors including ZEB1/2 proteins, TGF-β, Snail and cadherin proteins are discussed. Moreover, lncRNAs and circRNAs in crosstalk of miRNA/EMT regulation in these tumors are discussed and final impact on cancer metastasis and response of tumor cells to the chemotherapy is evaluated. Moreover, the impact of miRNAs transferred by exosomes in regulation of EMT in these cancers are discussed.

Epigenetic and Immunological Features of Bladder Cancer

Bladder cancer (BLCA) is one of the most common types of malignant tumors of the urogenital system in adults. Globally, the incidence of BLCA is more than 500,000 new cases worldwide annually, and every year, the number of registered cases of BLCA increases noticeably. Currently, the diagnosis of BLCA is based on cystoscopy and cytological examination of urine and additional laboratory and instrumental studies. However, cystoscopy is an invasive study, and voided urine cytology has a low level of sensitivity, so there is a clear need to develop more reliable markers and test systems for detecting the disease with high sensitivity and specificity. Human body fluids (urine, serum, and plasma) are known to contain significant amounts of tumorigenic nucleic acids, circulating immune cells and proinflammatory mediators that can serve as noninvasive biomarkers, particularly useful for early cancer detection, follow-up of patients, and personalization of their treatment. The review describes the most significant advances in epigenetics of BLCA.

Tissue-specific cancer stem/progenitor cells: Therapeutic implications

Surgical resection, chemotherapy, and radiation are the standard therapeutic modalities for treating cancer. These approaches are intended to target the more mature and rapidly dividing cancer cells. However, they spare the relatively quiescent and intrinsically resistant cancer stem cells (CSCs) subpopulation residing within the tumor tissue. Thus, a temporary eradication is achieved and the tumor bulk tends to revert supported by CSCs' resistant features. Based on their unique expression profile, the identification, isolation, and selective targeting of CSCs hold great promise for challenging treatment failure and reducing the risk of cancer recurrence. Yet, targeting CSCs is limited mainly by the irrelevance of the utilized cancer models. A new era of targeted and personalized anti-cancer therapies has been developed with cancer patient-derived organoids (PDOs) as a tool for establishing pre-clinical tumor models. Herein, we discuss the updated and presently available tissue-specific CSC markers in five highly occurring solid tumors. Additionally, we highlight the advantage and relevance of the three-dimensional PDOs culture model as a platform for modeling cancer, evaluating the efficacy of CSC-based therapeutics, and predicting drug response in cancer patients.

Expression and function of CD51 on CD8 T cells as an immunomodulatory target

T cell responses are regulated by co-stimulatory and inhibitory receptors along with T cell receptor- and cytokine-mediated signals. CD51 is a transmembrane glycoprotein of the integrin family that plays a role in cell adhesion, migration, tumorigenesis, and other cellular functions. In this study, we aimed to investigate the expression and function of CD51 on CD8 T cells. Upon in vitro T cell activation, CD51 expression was delayed but subsequently was upregulated in CD8 T cells upon cell division. Furthermore, CD51 was highly expressed in exhausted CD8 T cells in chronic LCMV infection, B16F10 melanoma, and CT26 colon carcinoma, and its expression level increased as cells became more differentiated. Using CRISPR-mediated knockdown, we found that the absence of CD51 led to a lower number of virus-specific CD8 T cells upon chronic lymphocytic choriomeningitis virus (LCMV) infection, although their granzyme B expression and cytokine production were maintained. Blocking CD51 also inhibited the in vitro proliferation of CD8 T cells. These results suggest that CD51 plays an important role in the early expansion of CD8 T cells and may have potential as an immunomodulatory target.

Involvement of redox signalling in tumour cell dormancy and metastasis

Decades of research on oncogene-driven carcinogenesis and gene-expression regulatory networks only started to unveil the complexity of tumour cellular and molecular biology. This knowledge has been successfully implemented in the clinical practice to treat primary tumours. In contrast, much less progress has been made in the development of new therapies against metastasis, which are the main cause of cancer-related deaths. More recently, the role of epigenetic and microenviromental factors has been shown to play a key role in tumour progression. Free radicals are known to communicate the intracellular and extracellular compartments, acting as second messengers and exerting a decisive modulatory effect on tumour cell signalling. Depending on the cellular and molecular context, as well as the intracellular concentration of free radicals and the activation status of the antioxidant system of the cell, the signalling equilibrium can be tilted either towards tumour cell survival and progression or cell death. In this regard, recent advances in tumour cell biology and metastasis indicate that redox signalling is at the base of many cell-intrinsic and microenvironmental mechanisms that control disseminated tumour cell fate and metastasis. In this manuscript, we will review the current knowledge about redox signalling along the different phases of the metastatic cascade, including tumour cell dormancy, making emphasis on metabolism and the establishment of supportive microenvironmental connections, from a redox perspective.

Natural compounds as a potential modifier of stem cells renewal: Comparative analysis

Cancer stem cells (CSCs) are indispensable for development, progression, drug resistance, and tumor metastasis. Current cancer-directed interventions target targeting rapidly dividing cancer cells and slow dividing CSCs, which are the root cause of cancer origin and recurrence. The most promising targets include several self-renewal pathways involved in the maintenance and renewal of CSCs, such as the Wnt/β-Catenin, Sonic Hedgehog, Notch, Hippo, Autophagy, and Ferroptosis. In view of safety, natural compounds are coming to the front line of treatment modalities for modifying various signaling pathways simultaneously involved in maintaining CSCs. Therefore, targeting CSCs with natural compounds is a promising approach to treating various types of cancers. In view of this, here we provide a comprehensive update on the current status of natural compounds that effectively tune key self-renewal pathways of CSCs. In addition, we highlighted surface expression markers in several types of cancer. We also emphasize how natural compounds target these self-renewal pathways to reduce therapy resistance and cancer recurrence properties of CSCs, hence providing valuable cancer therapeutic strategies. The inclusion of nutraceuticals is believed to enhance the therapeutic efficacy of current cancer-directed interventions significantly.

A systems biology investigation of curcumin potency against TGF-β-induced EMT signaling in lung cancer

Curcumin (diferuloylmethane) is bioactive phenolic compound which exerts diverse antimetastatic effect. Several studies have reported the antimetastatic effect of curcumin by its ability to modulate the epithelial-to-mesenchymal transition (EMT) process in different cancers, but underlying molecular mechanism is poorly understood. EMT is a highly conserved biological process in which epithelial cells acquire mesenchymal-like characteristics by losing their cell-cell junctions and polarity. As a consequence, deviation in cellular mechanism leads to cancer metastasis and thereby death. In this perspective, we explored the antimetastatic potential and mechanism of curcumin on the EMT process by establishing in vitro EMT model in lungs cancer (A549) cells induced by TGF-β1. Our results showed that curcumin mitigates EMT by regulating the expression of crucial mesenchymal markers such as MMP2, vimentin and N-cadherin. Besides, the transcriptional analysis revealed that the curcumin treatment differentially regulated the expression of 75 genes in NanoString nCounter platform. Further protein-protein interaction network and clusters analysis of differentially expressed genes revealed their involvement in essential biological processes that plays a key role during EMT transition. Altogether, the study provides a comprehensive overview of the antimetastatic potential of curcumin in TGF-β1-induced EMT in lung cancer cells.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03360-7.

Immune status for monitoring and treatment of bladder cancer

The high recurrence rate of non-muscle invasive bladder cancer (BC) and poor prognosis of advanced BC are therapeutic challenges that need to be solved. Bacillus Calmette-Guerin (BCG) perfusion was the pioneer immunotherapy for early BC, and the discovery of immune checkpoint inhibitors has created a new chapter in the treatment of advanced BC. The benefit of immunotherapy is highly anticipated, but its effectiveness still needs to be improved. In this review, we collated and analysed the currently available information and explored the mechaisms by which the internal immune imbalance of BC leads to tumour progression. The relationship between immunity and progression and the prognosis of BC has been explored through tests using body fluids such as blood and urine. These analytical tests have attempted to identify specific immuyne cells and cytokines to predict treatment outcomes and recurrence. The diversity and proportion of immune and matrix cells in BC determine the heterogeneity and immune status of tumours. The role and classification of immune cells have also been redefined, e.g., CD4 cells having recognised cytotoxicity in BC. Type 2 immunity, including that mediated by M2 macrophages, Th2 cells, and interleukin (IL)-13, plays an important role in the recurrence and progression of BC. Pathological fibrosis, activated by type 2 immunity and cancer cells, enhances the rate of cancer progression and irreversibility. Elucidating the immune status of BC and clarifying the mechanisms of action of different cells in the tumour microenvironment is the research direction to be explored in the future.

Construction and validation of a gene signature related to bladder urothelial carcinoma based on immune gene analysis

BACKGROUND

This study developed a gene signature associated with a malignant and common tumor of the urinary system, the Bladder Urothelial Carcinoma (BLCA).

METHODS

The Cancer Genome Atlas (TCGA) database was searched to obtain 414 BLCA samples and the expression spectra of 19 normal samples. Single-sample Gene Set Enrichment Analysis (ssGSEA) was conducted to determine the enrichment levels in the BLCA samples of the 29 immune genes. Unsupervised hierarchical clustering, gene set enrichment analysis (GSEA), single-factor Cox analysis, least absolute shrinkage and selection operator (LASSO) regression models, and GEO queues were used to determine the BLCA immune gene subtype, analyze the biological pathway differences between immune gene subtypes, determine the characteristic genes of BLCA associated with prognosis, identify the BLCA-related genes, and verify the gene signature, respectively.

RESULTS

We identified two immune gene subtypes (immunity_L and immunity_H). The latter was significantly related to receptors, JAK STAT signaling pathways, leukocyte interleukin 6 generation, and cell membrane signal receptor complexes. Four characteristic genes (RBP1, OAS1, LRP1, and AGER) were identified and constituted the gene signature. Significant survival advantages, higher mutation frequency, and superior immunotherapy were observed in the low-risk group patients. The gene signature had good predictive ability. The results of the validation group were consistent with TCGA queue results.

CONCLUSIONS

We constructed a 4-gene signature that helps monitor BLCA occurrence and prognosis, providing an important basis for developing personalized BLCA immunotherapy.

Cancer Stem Cells: From an Insight into the Basics to Recent Advances and Therapeutic Targeting

Cancer is characterized by an abnormal growth of the cells in an uncontrolled manner. These cells have the potential to invade and can eventually turn into malignancy, leading to highly fatal forms of tumor. Small subpopulations of cancer cells that are long-lived with the potential of excessive self-renewal and tumor formation are called cancer stem cells (CSCs) or cancer-initiating cells or tumor stem cells. CSCs can be found in tissues, such as breast, brain, lung, liver, ovary, and testis; however, their origin is still a matter of debate. These cells can differentiate and possess self-renewal capacity maintained by numerous intracellular signal transduction pathways, such as the Wnt/β-catenin signaling, Notch signaling, transforming growth factor-β signaling, and Hedgehog signaling. They can also contribute to numerous malignancies and are an important reason for tumor recurrence and metastasis because they are resistant to the known therapeutic strategies that mainly target the bulk of the tumor cells. This review contains collected and compiled information after analyzing published works of the last three decades. The goal was to gather information of recent breakthroughs related to CSCs, strategies to target CSCs' niche (e.g., nanotechnology with tumor biology), and their signaling pathways for cancer therapy. Moreover, the role of metformin, an antidiabetic drug, acting as a chemotherapeutic agent on CSCs by inhibiting cellular transformation and its selective killing is also addressed.

Single-Cell Transcriptome Comparison of Bladder Cancer Reveals Its Ecosystem

Bladder carcinoma (BLCA) is a highly heterogeneous disease, and the underlying biological behavior is still poorly understood. Here, single-cell RNA sequencing was performed on four clinical samples of different grades from three patients, and 26,792 cell transcriptomes were obtained revealing different tumor ecosystems. We found that N-glycan biosynthesis pathway was activated in high-grade tumor, but TNF-related pathway was activated in cystitis glandularis. The tumor microenvironment (TME) of different samples showed great heterogeneity. Notably, cystitis glandularis was dominated by T cells, low-grade and high-grade tumors by macrophages, while TME in patient with high-grade relapse by stromal cells. Our research provides single-cell transcriptome profiles of cystitis glandularis and BLCA in different clinical states, and the biological program revealed by single-cell data can be used as biomarkers related to clinical prognosis in independent cohorts.

Integrated Analysis of Energy Metabolism Signature-Identified Distinct Subtypes of Bladder Urothelial Carcinoma

Background: Bladder urothelial carcinoma (BLCA) is the most common type of bladder cancer. In this study, the correlation between the metabolic status and the outcome of patients with BLCA was evaluated using data from the Cancer Genome Atlas and Gene Expression Omnibus datasets.

Methods: The clinical and transcriptomic data of patients with BLCA were downloaded from the Cancer Genome Atlas and cBioPortal datasets, and energy metabolism-related gene sets were obtained from the Molecular Signature Database. A consensus clustering algorithm was then conducted to classify the patients into two clusters. Tumor prognosis, clinicopathological features, mutations, functional analysis, ferroptosis status analysis, immune infiltration, immune checkpoint-related gene expression level, chemotherapy resistance, and tumor stem cells were analyzed between clusters. An energy metabolism-related signature was further developed and verified using data from cBioPortal datasets.

Results: Two clusters (C1 and C2) were identified using a consensus clustering algorithm based on an energy metabolism-related signature. The patients with subtype C1 had more metabolism-related pathways, different ferroptosis status, higher cancer stem cell scores, higher chemotherapy resistance, and better prognosis. Subtype C2 was characterized by an increased number of advanced BLCA cases and immune-related pathways. Higher immune and stromal scores were also observed for the C2 subtype. A signature containing 16 energy metabolism-related genes was then identified, which can accurately predict the prognosis of patients with BLCA.

Conclusion: We found that the energy metabolism-associated subtypes of BLCA are closely related to the immune microenvironment, immune checkpoint-related gene expression, ferroptosis status, CSCs, chemotherapy resistance, prognosis, and progression of BLCA patients. The established energy metabolism-related gene signature was able to predict survival in patients with BLCA.

PDE4B Induces Epithelial-to-Mesenchymal Transition in Bladder Cancer Cells and Is Transcriptionally Suppressed by CBX7

Urinary bladder cancer (UBC) is a common malignant tumor with high incidence. Advances in the diagnosis and treatment of this disease demand the identification of novel therapeutic targets. Multiple studies demonstrated that PDE4B level was upregulated in malignancies and high PDE4B expression was correlated with poor outcomes. Herein, we identified that PDE4B was a potential therapeutic target in UBC. We confirmed that PDE4B expression was correlated with aggressive clinicopathological characteristics and unfavorable prognosis. Functional studies demonstrated that ectopic expression of PDE4B promoted UBC cells proliferation, migration and invasion, whereas PDE4B depletion suppressed cancer cell aggressiveness. We also identified CBX7 as a regulator of PDE4B to suppress the expression of PDE4B at the transcription level in a PRC1-dependent manner. Moreover, our results indicated that PDE4B induced epithelial-to-mesenchymal transition (EMT) in UBC cells via β-catenin pathway, whereas inhibition of PDE4B by its small molecule inhibitor, rolipram, effectively reversed the PDE4B overexpression-induced effects. To sum up, our results indicated that PDE4B acts as an oncogene by promoting UBC cell migration and invasion via β-catenin/EMT pathway.

Mammospheres of letrozole-resistant breast cancer cells enhance breast cancer aggressiveness

Aromatase inhibitors (AIs), such as letrozole, are considered as first-line treatment for estrogen receptor-positive breast cancer in postmenopausal women. Despite the successful use of letrozole, resistance to therapy, tumor relapse and metastasis remain principal causes of patient mortality. Although there is no therapy currently available for AI-resistant breast cancer, previous reports have demonstrated that AI resistance is associated with hormone independence, increased growth factor signaling, enhanced cellular motility and epithelial to mesenchymal transition (EMT). This suggests a convergence of EMT and cancer stem cells (CSCs) in endocrine resistance. The present study evaluated the contribution of mammospheres in letrozole-resistant breast cancer by characterizing mammospheres and their potential impact on cellular motility. Ovariectomized immunocompromised female mice were inoculated in the mammary fat pad with either letrozole-resistant MCF-7 cells (LTLT-Ca) or letrozole-sensitive MCF-7 cells (AC-1). Subsequently, intratumoral CSC marker expression was assessed by immunohistochemistry. The results indicated that LTLT-Ca tumors were CD44+/CD24+, while AC-1 tumors presented low CD44/CD24 expression. Since mammosphere formation depends on CSCs, both cell lines were cultured either adherently (2D) or as mammospheres (3D) to assess the CD44/CD24 protein expression profile. When 3D culturing both cell lines, higher expression levels of CD44 and CD24 were observed when compared with their adherent counterparts, with the most robust change observed in the LTLT-Ca cell line. To quantitate the breast cancer stem cell activity, mammosphere formation assays were performed, and the LTLT-Ca cells formed mammospheres at a 3.4-fold higher index compared with AC-1 cells. Additionally, targeted gene expression arrays were conducted to compare the LTLT-Ca 3D and 2D cells, revealing that LTLT-Ca 3D cells displayed decreased expression levels of genes involved in cell adhesion and tumor suppression (e. g., E-cadherin, caveolin 1 and β-catenin). To validate this finding, wound healing assays were performed, and LTLT-Ca mammospheres exhibited a 70% wound closure, whereas AC-1 mammospheres exhibited a 39% wound closure. Collectively, the present findings demonstrated a strong association between AI-resistant mammospheres and an increased propensity for migration, which may be indicative of a poor prognosis.

Site-specific differences in survival among upper and lower tract urothelial carcinoma patients treated with radical surgery

BACKGROUND

It currently remains unclear whether the location of primary tumours affects the clinical outcomes of patients with locally advanced urothelial carcinoma in the urinary tract. The aim of the present study was to compare prognostic differences between bladder urothelial carcinoma and upper tract urothelial carcinoma, particularly pT3 or higher tumours.

METHODS

In total, 307 patients with pT3 or higher urothelial carcinoma without distant metastasis who underwent radical cystectomy for bladder urothelial carcinoma (N = 127, 41.4%) or radical nephroureterectomy for upper tract urothelial carcinoma (N = 180, 58.6%) at Keio University Hospital and three affiliated hospitals between 1994 and 2017 were enrolled. Oncological outcomes were compared between bladder urothelial carcinoma and upper tract urothelial carcinoma using Cox regression analysis.

RESULTS

Significantly higher rates of male patients, smokers, neoadjuvant chemotherapy, lymph node involvement and lymphovascular invasion were observed in the bladder urothelial carcinoma group. The incidence of regional lymph node or local recurrence was higher in patients with bladder urothelial carcinoma than in those with upper tract urothelial carcinoma, while that of lung metastasis was lower. In all patients, bladder urothelial carcinoma was independently associated with disease recurrence (hazard ratio (HR) 1.504, P = 0.035) in addition to neoadjuvant chemotherapy and lymphovascular invasion. Bladder urothelial carcinoma was also independently associated with cancer death (HR = 1.998, P = 0.002) as well as lymphovascular invasion. Following the exclusion of patients who received neoadjuvant chemotherapy, bladder urothelial carcinoma remained an independent risk factor for disease recurrence and cancer death (HR = 1.702, P = 0.010 and HR = 1.888, P = 0.013, respectively).

CONCLUSIONS

Bladder urothelial carcinoma may follow worse prognosis compared to upper tract urothelial carcinoma, particularly that with a high pathological stage.

ABT‑737, a Bcl‑2 family inhibitor, has a synergistic effect with apoptosis by inducing urothelial carcinoma cell necroptosis

ABT‑737 is a recently reported inhibitor of members of the Bcl‑2 family of apoptosis regulators. However, to the best of our knowledge, its necroptosis‑inducing function in bladder cancer has not yet been researched. Thus, the present study aimed to investigate whether this Bcl‑2 family inhibitor can induce both apoptosis and necroptosis of urothelial carcinoma cells. The proliferation and survival of urothelial carcinoma cell lines treated with a combination of both Z‑VAD‑FMK as a pan‑caspase inhibitor and ABT‑737 were assessed in vitro. Z‑DNA binding protein 1 (ZBP1), receptor‑interacting protein (RIP)1 and RIP3 were knocked down using small interfering RNA in urothelial carcinoma cell lines. The protein expression levels of ZBP1, RIP1 and RIP3 following cell transfection were measured via western blot analysis. Cell viability was determined using an MTT assay. Cell invasion was examined using cell invasion assays. The expression levels of necroptosis‑related proteins, high mobility group box 1, ZBP1, mixed‑lineage kinase domain‑like protein (MLKL) and RIP3, were measured via western blotting. It was found that ABT‑737 inhibited the proliferation and invasion of bladder cancer cells by inducing cell necrosis. The data demonstrated that ZBP1 and RIP3 have main roles in the cell necrosis induced by ABT‑737. In addition, RIP3 and ZBP1, without interacting with RIP1, directly induced MLKL‑mediated programmed cell necrosis. Thus, understanding how urothelial carcinoma cells react to Bcl‑2 family inhibitors may accelerate the discovery of drugs to treat bladder cancer.

An integrated multi-omics analysis identifies prognostic molecular subtypes of non-muscle-invasive bladder cancer

The molecular landscape in non-muscle-invasive bladder cancer (NMIBC) is characterized by large biological heterogeneity with variable clinical outcomes. Here, we perform an integrative multi-omics analysis of patients diagnosed with NMIBC (n = 834). Transcriptomic analysis identifies four classes (1, 2a, 2b and 3) reflecting tumor biology and disease aggressiveness. Both transcriptome-based subtyping and the level of chromosomal instability provide independent prognostic value beyond established prognostic clinicopathological parameters. High chromosomal instability, p53-pathway disruption and APOBEC-related mutations are significantly associated with transcriptomic class 2a and poor outcome. RNA-derived immune cell infiltration is associated with chromosomally unstable tumors and enriched in class 2b. Spatial proteomics analysis confirms the higher infiltration of class 2b tumors and demonstrates an association between higher immune cell infiltration and lower recurrence rates. Finally, the independent prognostic value of the transcriptomic classes is documented in 1228 validation samples using a single sample classification tool. The classifier provides a framework for biomarker discovery and for optimizing treatment and surveillance in next-generation clinical trials.

MicroRNAs: Their Role in Metastasis, Angiogenesis, and the Potential for Biomarker Utility in Bladder Carcinomas

Angiogenesis is the process of generating new capillaries from pre-existing blood vessels with a vital role in tumor growth and metastasis. MicroRNAs (miRNAs) are noncoding RNAs that exert post-transcriptional control of protein regulation. They participate in the development and progression of several cancers including bladder cancer (BLCA). In cancer tissue, changes in microRNA expression exhibit tissue specificity with high levels of stability and detectability. miRNAs are less vulnerable to degradation, making them novel targets for therapeutic approaches. A suitable means of targeting aberrant activated signal transduction pathways in carcinogenesis of BLCA is possibly through altering the expression of key miRNAs that regulate them, exerting a strong effect on signal transduction. Precaution must be taken, as the complexity of miRNA regulation might result in targeting several downstream tumor suppressors or oncogenes, enhancing the effect further. Since exosomes contain both mRNA and miRNA, they could therefore possibly be more effective in targeting a recipient cell if they deliver a specific miRNA to modify the recipient cell protein production and gene expression. In this review, we discuss the molecules that have been shown to play a significant role in BLCA tumor development. We also discuss the roles of various miRNAs in BLCA angiogenesis and metastasis. Advances in the management of metastatic BLCA have been limited; miRNA mimics and molecules targeted at miRNAs (anti-miRs) as well as exosomes could serve as therapeutic modalities or as diagnostic biomarkers.

The Identification of Small Molecule Inhibitors That Reduce Invasion and Metastasis of Aggressive Cancers

Transformed epithelial cells can activate programs of epithelial plasticity and switch from a sessile, epithelial phenotype to a motile, mesenchymal phenotype. This process is linked to the acquisition of an invasive phenotype and the formation of distant metastases. The development of compounds that block the acquisition of an invasive phenotype or revert the invasive mesenchymal phenotype into a more differentiated epithelial phenotype represent a promising anticancer strategy. In a high-throughput assay based on E-cadherin (re)induction and the inhibition of tumor cell invasion, 44,475 low molecular weight (LMW) compounds were screened. The screening resulted in the identification of candidate compounds from the PROAM02 class. Selected LMW compounds activated E-cadherin promoter activity and inhibited cancer cell invasion in multiple metastatic human cancer cell lines. The intraperitoneal administration of selected LMW compounds reduced the tumor burden in human prostate and breast cancer in vivo mouse models. Moreover, selected LMW compounds decreased the intra-bone growth of xenografted human prostate cancer cells. This study describes the identification of the PROAM02 class of small molecules that can be exploited to reduce cancer cell invasion and metastases. Further clinical evaluation of selected candidate inhibitors is warranted to address their safety, bioavailability and antitumor efficacy in the management of patients with aggressive cancers.

Kynurenine 3-monooxygenase upregulates pluripotent genes through β-catenin and promotes triple-negative breast cancer progression

Background

Triple-negative breast cancer (TNBC) is aggressive and has a poor prognosis. Kynurenine 3-monooxygenase (KMO), a crucial kynurenine metabolic enzyme, is involved in inflammation, immune response and tumorigenesis. We aimed to study the role of KMO in TNBC.

Methods

KMO alteration and expression data from public databases were analyzed. KMO expression levels in TNBC samples were analyzed using immunohistochemistry. Knockdown of KMO in TNBC cells was achieved by RNAi and CRISPR/Cas9. KMO functions were examined by MTT, colony-forming, transwell migration/invasion, and mammosphere assays. The molecular events were analyzed by cDNA microarrays, Western blot, quantitative real-time PCR and luciferase reporter assays. Tumor growth and metastasis were detected by orthotopic xenograft and tail vein metastasis mouse models, respectively.

Findings

KMO was amplified and associated with worse survival in breast cancer patients. KMO expression levels were higher in TNBC tumors compared to adjacent normal mammary tissues. In vitro ectopic KMO expression increased cell growth, colony and mammosphere formation, migration, invasion as well as mesenchymal marker expression levels in TNBC cells. In addition, KMO increased pluripotent gene expression levels and promoter activities in vitro. Mechanistically, KMO was associated with β-catenin and prevented β-catenin degradation, thereby enhancing the transcription of pluripotent genes. KMO knockdown suppressed tumor growth and the expression levels of β-catenin, CD44 and Nanog. Furthermore, mutant KMO (known with suppressed enzymatic activity) could still promote TNBC cell migration/invasion. Importantly, mice bearing CRISPR KMO-knockdown TNBC tumors showed decreased lung metastasis and prolonged survival.

Interpretation

KMO regulates pluripotent genes via β-catenin and plays an oncogenic role in TNBC progression.

Collision tumors of the lung: A case report of urothelial carcinoma metastasizing to renal cell carcinoma with heterotopic ossification

Collision tumors are rare entities that consist of at least two or more histologically and ontologically distinct tumor types within the same organ. It is still not well understood how collision tumors form; yet, three main theories have been proposed to explain the pathogenesis, including the “random collision effect,” “field cancerization,” and “tumor-to-tumor carcinogenesis.” Collision tumors have been encountered in various body organs, including the lung. They either consist of a metastasizing tumor colliding with primary cancer or distinct primary or metastatic cancers colliding together. Here, we describe a rare case of collision tumors of the lung that consists of two metastatic carcinomas, namely renal cell carcinoma and urothelial carcinoma of the bladder. We propose that the urothelial carcinoma disseminated into several pre-existing pulmonary metastases of renal cell carcinoma with heterotopic bone formation. The possible mechanisms underlying the development of this peculiar tumor are discussed.

Patient-derived tumour models for personalized therapeutics in urological cancers

Preclinical knowledge of dysregulated pathways and potential biomarkers for urological cancers has undergone limited translation into the clinic. Moreover, the low approval rate of new anticancer drugs and the heterogeneous drug responses in patients indicate that current preclinical models do not always reflect the complexity of malignant disease. Patient-derived tumour models used in preclinical uro-oncology research include 3D culture systems, organotypic tissue slices and patient-derived xenograft models. Technological innovations have enabled major improvements in the capacity of these tumour models to reproduce the clinical complexity of urological cancers. Each type of patient-derived model has inherent advantages and limitations that can be exploited, either alone or in combination, to gather specific knowledge on clinical challenges and address unmet clinical needs. Nevertheless, few opportunities exist for patients with urological cancers to benefit from personalized therapeutic approaches. Clinical validation of experimental data is needed to facilitate the translation and implementation of preclinical knowledge into treatment decision making.

Value of tumour-infiltrating immune cells in predicting response to intravesical BCG in patients with non-muscle-invasive bladder cancer: a systematic review and meta-analysis

OBJECTIVE

To investigate the predictive value of tumour-infiltrating immune cells (TIICs) on oncological outcomes and response to BCG treatment in patients with non-muscle-invasive bladder cancer (NMIBC).

MATERIALS AND METHODS

A systematic review and meta-analysis was performed using PubMed, Scopus and the Cochrane Library in July 2020 to identify relevant studies according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The pooled recurrence-free survival (RFS) rate was calculated using a fixed-effect model.

RESULTS

We retrieved 15 studies (including 791 patients) evaluating the effect of TIICs on oncological outcomes in patients with NMIBC treated with intravesical BCG. TIICs were reported to be a significant predictor of oncological outcomes and response to BCG treatment in 10 studies. Tumour-associated macrophages were associated with worse RFS (pooled hazard ratio 2.30, 95% confidence interval 1.64-3.22).

CONCLUSIONS

Based on these data, TIICs are significant predictors of RFS and response to BCG treatment in patients with NMIBC; therefore, incorporation of TIICs into risk stratification models may help patients and physicians in the clinical decision-making process in order to achieve the maximum possible benefit from BCG treatment.

Activation of PPARγ and inhibition of cell proliferation reduces key proteins associated with the basal subtype of bladder cancer in As3+-transformed UROtsa cells

Environmental exposure to arsenite (As³⁺) has a strong association with the development of human urothelial cancer (UC) and is the 5^th most common cancer in men and the 12^th most common cancer in women. Muscle invasive urothelial cancer (MIUC) are grouped into basal or luminal molecular subtypes based on their gene expression profile. The basal subtype is more aggressive and can be associated with squamous differentiation, characterized by high expression of keratins (KRT1, 5, 6, 14, and 16) and epidermal growth factor receptor (EGFR) within the tumors. The luminal subtype is less aggressive and is predominately characterized by elevated gene expression of peroxisome proliferator-activated receptor- gamma (PPARγ) and forkhead box protein A1 (FOXA1). We have previously shown that As³⁺-transformed urothelial cells (As-T) exhibit a basal subtype of UC expressing genes associated with squamous differentiation. We hypothesized that the molecular subtype of the As-T cells could be altered by inducing the expression of PPARγ and/or inhibiting the proliferation of the cells. Non-transformed and As-T cells were treated with Troglitazone (TG, PPARG agonist, 10 μM), PD153035 (PD, an EGFR inhibitor, 1 μM) or a combination of TG and PD for 3 days. The results obtained demonstrate that treatment of the As-T cells with TG upregulated the expression of PPARγ and FOXA1 whereas treatment with PD decreased the expression of some of the basal keratins. However, a combined treatment of TG and PD resulted in a consistent decrease of several proteins associated with the basal subtype of bladder cancers (KRT1, KRT14, KRT16, P63, and TFAP2A). Our data suggests that activation of PPARγ while inhibiting cell proliferation facilitates the regulation of genes involved in maintaining the luminal subtype of UC. In vivo animal studies are needed to address the efficacy of using PPARγ agonists and/or proliferation inhibitors to reduce tumor grade/stage of MIUC.

Jagged2 progressively increased expression from Stage I to III of Bladder Cancer and Melatonin-mediated downregulation of Notch/Jagged2 suppresses the Bladder Tumorigenesis via inhibiting PI3K/AKT/mTOR/MMPs signaling

Background: This study assessed the expression of Jagged2 in human bladder cancer (BC) tested the hypothesis that melatonin (Mel) inhibited the tumorigenesis of BC cells mainly through downregulating the Notch/Jagged2 and PI3K/AKT/mTOR/MMPs^(2&9) signaling pathways.

Methods and Results: Tissue array from BC patients showed that the gene and protein expressions of JAG2/Jagged2 were significantly upregulated from T1 to T3 (primary tumor size) and from stage I to III (all p<0.001). In vitro study showed that in BC cell line of UMUC3, the cellular and protein expressions of Jagged2 were significantly attenuated in Mel-treated UMUC3 and further attenuated in UMUC3 shRNA silenced Notch/JAG2 (UMUC3^KD) than in UMUC3 only (all p<0.0001). The protein expressions of Notch/Jagged2/MMPs^(2&9)/PI3K/p-AKT/mTOR/p53/ratio of LC3BII/LC3B-I were significantly progressively reduced from UMUC3 to UMUC3+Mel/1.0mM, further to UMUC3+Mel/2.0mM and furthermore to UMUC3^KD (all p<0.0001). The cell proliferation/invasion/colony formation/healing-process were significantly inhibited in Mel-treated/2.0mM UMUC3 and further significantly inhibited in UMUC3^KD regardless of Mel treatment as compared with UMUC3 only (all p<0.0001). By day 28 after UMUC3 implanted into nude mouse back, the BC weight/volume were significantly reduced in UMUC3+Mel (100 mg/kg/day) and furthermore reduced in UMUC3^KD (all p<0.0001) as compared with UMUC3 only (all p<0.0001). The cellular (MMPs^(2&9)/Notch/Jagged2) and protein (Notch/Jagged2/PI3K/p-AKT/mTOR/MMPs^(2&9)) exhibited a similar trend, whereas the PTEN protein level exhibited an opposite pattern of PI3K among three groups (all p<0.0001).

Conclusion: Notch/Jagged-PI3K/p-AKT/mTOR/MMPs is one essential signaling pathway for BC survival, proliferation and invasion that were remarkably suppressed by Mel treatment.

High prevalence of airway obstruction and pulmonary emphysema in urothelial (renal pelvis, ureter, and bladder) cancer patients

BACKGROUND

Cigarette smoking is a major cause of COPD, with patients also presenting complications that stem from other smoking-related diseases, including urothelial cancer. However, the prevalence of COPD or airflow obstruction in urothelial cancer patients has not been well studied.

METHODS

We investigated the prevalence of airflow obstruction (FEV1/FVC < 70%) in newly diagnosed urothelial cancer patients and identified the risk factors for airflow obstruction in existing urothelial cancer patients. Additionally, we compared the characteristics of subjects who had been diagnosed with both airflow obstruction and urothelial cancer, and subjects whose airflow obstruction was discovered during health screenings.

RESULTS

A total of 217 patients were newly diagnosed with urothelial cancer during the study period at our institution. Among all patients, 210 (96.8%) underwent an evaluable lung function test, in which 38.6% (81 patients) displayed airflow obstruction defined as FEV1/FVC < 70%. In urothelial cancer patients, age, smoking index (pack-years), and BMI proved to be significant risk factors for airflow obstruction in multivariate logistic regression (p = 0.007, p < 0.0001, and p = 0.035, respectively). Gender, cancer stage, and cancer location were not significant risk factors. Patients with both airflow obstruction and urothelial cancer showed a more advanced emphysematous change than subjects presenting with airflow obstruction alone (unpaired t-test, p = 0.0003).

CONCLUSIONS

Airflow obstruction was identified in 38.6% of urothelial cancer patients. Age, smoking index (pack-years), and BMI were significant risk factors. A significantly higher emphysematous score was observed in subjects with urothelial cancer than in subjects with airway obstruction alone.

Single-cell RNA sequencing reveals the tumor microenvironment and facilitates strategic choices to circumvent treatment failure in a chemorefractory bladder cancer patient

BACKGROUND

Tumor cell-intrinsic mechanisms and complex interactions with the tumor microenvironment contribute to therapeutic failure via tumor evolution. It may be possible to overcome treatment resistance by developing a personalized approach against relapsing cancers based on a comprehensive analysis of cell type-specific transcriptomic changes over the clinical course of the disease using single-cell RNA sequencing (scRNA-seq).

METHODS

Here, we used scRNA-seq to depict the tumor landscape of a single case of chemo-resistant metastatic, muscle-invasive urothelial bladder cancer (MIUBC) addicted to an activating Harvey rat sarcoma viral oncogene homolog (HRAS) mutation. In order to analyze tumor evolution and microenvironmental changes upon treatment, we also applied scRNA-seq to the corresponding patient-derived xenograft (PDX) before and after treatment with tipifarnib, a HRAS-targeting agent under clinical evaluation.

RESULTS

In the parallel analysis of the human MIUBC and the PDX, diverse stromal and immune cell populations recapitulated the cellular composition in the human and mouse tumor microenvironment. Treatment with tipifarnib showed dramatic anticancer effects but was unable to achieve a complete response. Importantly, the comparative scRNA-seq analysis between pre- and post-tipifarnib-treated PDX revealed the nature of tipifarnib-refractory tumor cells and the tumor-supporting microenvironment. Based on the upregulation of programmed death-ligand 1 (PD-L1) in surviving tumor cells, and the accumulation of multiple immune-suppressive subsets from post-tipifarnib-treated PDX, a PD-L1 inhibitor, atezolizumab, was clinically applied; this resulted in a favorable response from the patient with acquired resistance to tipifarnib.

CONCLUSION

We presented a single case report demonstrating the power of scRNA-seq for visualizing the tumor microenvironment and identifying molecular and cellular therapeutic targets in a treatment-refractory cancer patient.

Expression of E-cadherin, Ki-67, and p53 in urinary bladder cancer in relation to progression, survival, and recurrence

Although the incidence varies with age and gender, urothelial bladder cancer is a relatively frequently occurring malignancy with variable clinical behavior that often has high recurrence rates. In this study, we analyzed the tumor tissues of 224 patients with pTa, pT1, and pT2 urinary bladder cancer. We performed a histomorphologic analysis and immunohistochemistry for p53, Ki-67, and E-cadherin, which were selected as markers of the malignant process. For pTa and pT1, univariate analyses of cancer-specific survival (CSS), progression-free survival (PFS), and recurrence-free survival (RFS) were calculated using the Kaplan-Meier method, the logrank test and Cox regression. Multivariate analysis was performed by the Cox regression analysis. Ki-67 (P<0.001) was significantly associated with CSS, but the highest association was shown for E-cadherin (P<0.001). For pT1 and pTa, the Kaplan-Meier analysis and the log-rank test revealed significantly worse PFS for patients with higher levels of Ki-67 (P<0.001) and lower levels of E-cadherin (P<0.001). Based on these obtained results, it can be clearly stated that Ki-67 and E-cadherin expression levels are associated with CSS, PFS and RFS. The clinical utility of these markers is valuable for pTa and pT1 urinary bladder cancer and should be further verified with prospective multi-center trials.

Targeting cancer stem cell pathways for cancer therapy

Since cancer stem cells (CSCs) were first identified in leukemia in 1994, they have been considered promising therapeutic targets for cancer therapy. These cells have self-renewal capacity and differentiation potential and contribute to multiple tumor malignancies, such as recurrence, metastasis, heterogeneity, multidrug resistance, and radiation resistance. The biological activities of CSCs are regulated by several pluripotent transcription factors, such as OCT4, Sox2, Nanog, KLF4, and MYC. In addition, many intracellular signaling pathways, such as Wnt, NF-κB (nuclear factor-κB), Notch, Hedgehog, JAK-STAT (Janus kinase/signal transducers and activators of transcription), PI3K/AKT/mTOR (phosphoinositide 3-kinase/AKT/mammalian target of rapamycin), TGF (transforming growth factor)/SMAD, and PPAR (peroxisome proliferator-activated receptor), as well as extracellular factors, such as vascular niches, hypoxia, tumor-associated macrophages, cancer-associated fibroblasts, cancer-associated mesenchymal stem cells, extracellular matrix, and exosomes, have been shown to be very important regulators of CSCs. Molecules, vaccines, antibodies, and CAR-T (chimeric antigen receptor T cell) cells have been developed to specifically target CSCs, and some of these factors are already undergoing clinical trials. This review summarizes the characterization and identification of CSCs, depicts major factors and pathways that regulate CSC development, and discusses potential targeted therapy for CSCs.

Significance of Bladder Neck Involvement in Risk Substratification of Intermediate-Risk Non-muscle-invasive Bladder Cancer

BACKGROUND

Intermediate-risk non-muscle-invasive bladder cancer (NMIBC) involves heterogeneous patients, resulting in uncertainty regarding its prognosis and the indication of adjuvant therapy. Previous studies suggested a correlation between tumor location, especially bladder neck involvement (BNI), and patient prognosis of NMIBC.

OBJECTIVE

We investigated the role of BNI in risk substratification of intermediate-risk NMIBC patients.

DESIGN, SETTING, AND PARTICIPANTS

This single-institutional study included 436 primary or recurrent intermediate-risk NMIBC patients based on risk stratification in the European Association of Urology guidelines.

INTERVENTION

All patients underwent transurethral resection of the bladder tumor.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary and secondary endpoints were progression and recurrence, respectively. The associations of BNI with the endpoints were examined using the Kaplan-Meier method and the Cox proportional hazards model.

RESULTS AND LIMITATIONS

Overall, 205 (47%) patients had multiple tumors and 276 (63%) underwent intravesical therapy. BNI was observed in 53 (12%) patients. During the median follow-up of 42 mo, 12 (3%) and 211 (48%) patients experienced progression and recurrence, respectively. Multivariate analysis showed that BNI was an independent predictor for both progression (hazard ratio 10.98, p < 0.001) and recurrence (hazard ratio 2.12, p < 0.001). The progression rate was significantly higher in patients with BNI compared with those without BNI (13% vs 1% at 3 yr and 20% vs 1% at 6 yr; p < 0.001). Analogous findings were observed for recurrence. The progression rate was more remarkably stratified by BNI in 103 recurrent cases (17% vs 3% at 3 yr and 34% vs 3% at 6 yr in patients with vs without BNI; p < 0.001). A limitation of this study was its retrospective nature.

CONCLUSIONS

BNI substratified intermediate-risk NMIBC patients well regarding their risks of progression and recurrence, which could help determine follow-up and therapeutic strategies for these patients.

PATIENT SUMMARY

The associations of bladder neck involvement with progression and recurrence were evaluated in patients with intermediate-risk non-muscle-invasive bladder cancer. We found that bladder neck involvement was a good factor for substratifying patients based on their risks of progression and recurrence. Bladder neck involvement can be useful in determining follow-up and therapeutic strategies for intermediate-risk non-muscle-invasive bladder cancer.

Prognostic Role of Epithelial-Mesenchymal Transition Markers "E-Cadherin, β-Catenin, ZEB1, ZEB2 and p63" in Bladder Carcinoma

Background

This study aimed to investigate the expression of epithelial-mesenchymal markers’ E-cadherin, β-catenin, zinc-finger E-box-binding homeobox 1 (ZEB1), zinc-finger E-box-binding homeobox 2 (ZEB2) and p63 in transitional cell carcinoma (TCC) and squamous cell carcinoma (SCC) variants of bladder carcinoma (BC) and their correlation with clinicopathological parameters of prognostic importance.

Methods

In this retrospective study, 91 patients were enrolled (66 with TCC and 25 with SCC). All patients had full clinical and follow-up data and available paraffin blocks. Immunohistochemical analysis was performed and correlated with clinicopathological factors.

Results

In TCC cases, reduced E-cadherin, β-catenin positivity and p63 expression rate were evident in the sitting of increased expression of ZEB1 and ZEB2. Patients with ZEB2 positive tumors were more likely to die compared to those with negative ZEB2 (P = 0.024). Moreover, in patients with muscle-invasive BCs, an intense p63 expression was associated with poor overall survival (OS) (P < 0.001). For patients with SCC, there was a reduction in E-cadherin and β-catenin positivity with elevated p63 expression and concomitant increased ZEB1 and ZEB2 expression. Poor prognosis was evident in association with reduced E-cadherin, positive nuclear β-catenin/reduced membranous β-catenin, ZEB1 and ZEB2 positive cases as well patients with elevated p63 expression (P < 0.001). TCC and SCC cases showed similar poor prognosis in association with elevated p63 expression (P < 0.001).

Conclusions

In both TCC and SCC variants, epithelial-mesenchymal transition (EMT) process is evident; however, its molecular mechanism shows some variations, specifically this notably different p63 expression pattern among two carcinoma variants with the similar impact of elevated p63 expression pattern on prognosis.

Insights on CXC chemokine receptor 2 in breast cancer: An emerging target for oncotherapy

Breast cancer is the most common malignant neoplasm in women worldwide, and the treatment regimens currently available are far from optimal. Targeted therapy, based on molecular typing of breast cancer, is the most precise form of treatment, and CXC chemokine receptor 2 (CXCR2) is one of the molecular markers used in targeted therapies. As a member of the seven transmembrane G-protein-coupled receptor family, CXCR2 and its associated ligands have been increasingly implicated in tumor-associated processes. These processes include proliferation, angiogenesis, invasion, metastasis, chemoresistance, and stemness and phenotypic maintenance of cancer stem cells. Thus, the inhibition of CXCR2 or its downstream signaling pathways could significantly attenuate tumor progression. Therefore, studies on the biological functions of CXCR2 and its association with neoplasia may help improve the prognosis of breast cancer. Furthermore, the targeting of CXCR2 could supplement the present clinical approaches of breast cancer treatment strategies. The present review discusses the structures and mechanisms of CXCR2 and its ligands. Additionally, the contribution of CXCR2 to the development of breast cancer and its potential therapeutic benefits are also discussed.

Does reduced E-cadherin expression correlate with poor prognosis in patients with upper tract urothelial cell carcinoma?: A systematic review and meta-analysis

BACKGROUND

E-cadherin has emerged as a prognostic factor of urothelial cell carcinoma. In the present work we investigate the relationship between expression of E-cadherin and clinical outcomes, following radical nephroureterectomy for upper tract urothelial cell carcinoma.

METHODS

We systematically searched PubMed, Embase, Cochrane Library, and Web of Science databases to identify eligible studies published until July 2017.

RESULT

Six studies were included in the meta-analysis, with a total of 1014 patients. The pooled hazard ratio (HR) for recurrence-free survivor was 0.69 (95% confidence interval [CI], 0.44-1.09, I = 63%, P = .04). Also, reduced E-cadherin was not significantly associated with poor cancer-specific survivor (pooled HR, 1.40; 95% CI, 0.66-1.43, I = 54%, P = .11). The pooled HR for overall survivor was not statistically significant (pooled HR, 0.68; 95% CI, 0.32-1.46, I = 80%, P = .007). The results of the Begg and Egger tests suggested that publication bias was not evident in this meta-analysis.

CONCLUSIONS

Reduced E-cadherin expression did not appear to be significantly associated with disease prognosis after nephroureterectomy in the meta-analysis. However, further high quality, prospective studies are warranted to better address this issue.

c-Myc Acts as a Competing Endogenous RNA to Sponge miR-34a, in the Upregulation of CD44, in Urothelial Carcinoma

MicroRNAs (miRNAs) have been shown to play a crucial role in the progression of human cancers, including urothelial carcinoma (UC), the sixth-most common cancer in the world. Among them, miR-34a has been implicated in the regulation of cancer stem cells (CSCs); however, its role in UC has yet to be fully elucidated. In this study, bioinformatics and experimental analysis confirmed that miR-34a targets CD44 (a CSC surface marker) and c-Myc (a well-known cell cycle regulator) in UC. We found that, surprisingly, most UC cell lines and patient samples did express miR-34a, although epigenetic silencing by promoter hypermethylation of miR-34a expression was observed only in UMUC3 cells, and a subset of patient samples. Importantly, overexpression of c-Myc, a frequently amplified oncogene in UC, was shown to upregulate CD44 expression through a competing endogenous RNA (ceRNA) mechanism, such that overexpression of the c-Myc 3'UTR upregulated CD44, and vice versa. Importantly, we observed a positive correlation between the expression of c-Myc and CD44 in clinical samples obtained from UC patients. Moreover, overexpression of a dominant-negative p53 mutant downregulated miR-34a, but upregulated c-Myc and CD44, in UC cell lines. Functionally, the ectopic expression of miR-34a was shown to significantly suppress CD44 expression, and subsequently, suppression of cell growth and invasion capability, while also reducing chemoresistance. In conclusion, it appears that aberrant promoter methylation, and c-Myc-mediated ceRNA mechanisms, may attenuate the function of miR-34a, in UC. The tumor suppressive role of miR-34a in controlling CSC phenotypes in UC deserves further investigation.

A review on the role of M2 macrophages in bladder cancer; pathophysiology and targeting

Tumor-associated macrophages (TAMs) which are often referred to as immunosuppressive cells (M2 macrophage), constitute a subset of tumor microenvironment cells and affect tumor progression in solid tumors. Recently, these cells have gained remarkable importance as therapeutic candidates for solid tumors. In bladder cancer, major studies have focused on evaluating TAMs in response to Bacillus Calmette-Guerin (BCG) therapy. M2 macrophages may directly impact the BCG-induced immune responses against tumor in bladder cancer. They are the main inhibitors of the tumor microenvironment that promotes growth and metastasis of the tumor. However, the clinical significance of M2 macrophages in bladder cancer is controversial. In this review, we will discuss the clinical significance of M2 macrophages in prognosis of bladder cancer as well as worth of their potential targeting in bladder cancer treatment. In the following, we will introduce important factors resulting in M2 macrophage promotion and also experimental therapeutic agents that may cause the inhibition of bladder cancer tumor growth.

Defining the Hallmarks of Metastasis

Metastasis is the primary cause of cancer morbidity and mortality. The process involves a complex interplay between intrinsic tumor cell properties as well as interactions between cancer cells and multiple microenvironments. The outcome is the development of a nearby or distant discontiguous secondary mass. To successfully disseminate, metastatic cells acquire properties in addition to those necessary to become neoplastic. Heterogeneity in mechanisms involved, routes of dissemination, redundancy of molecular pathways that can be utilized, and the ability to piggyback on the actions of surrounding stromal cells makes defining the hallmarks of metastasis extraordinarily challenging. Nonetheless, this review identifies four distinguishing features that are required: motility and invasion, ability to modulate the secondary site or local microenvironments, plasticity, and ability to colonize secondary tissues. By defining these first principles of metastasis, we provide the means for focusing efforts on the aspects of metastasis that will improve patient outcomes.

Imatinib inhibits the regrowth of human colon cancer cells after treatment with 5-FU and cooperates with vitamin D analogue PRI-2191 in the downregulation of expression of stemness-related genes in 5-FU refractory cells

Conventional cytotoxic drugs preferentially eliminate differentiated cancer cells but spare relatively more resistant stem-like cancer cells capable to initiate recurrence. Due to cancer cell plasticity, the stem-like phenotype can be also acquired by cancer cells refractory to treatment with cytotoxic drugs. We investigated whether drugs inhibiting receptor tyrosine kinases could be used to target human colon cancer cells initiating cancer regrowth following conventional cytotoxic treatment. The moderately differentiated cell line HT-29 and poorly differentiated cell line HCT-116 were exposed to 5-fluorouracil (5-FU). Cells that resisted the exposure to 5-FU were subsequently treated with imatinib or sunitinib. Both drugs reduced clonogenicity of 5-FU-refractory cells under normoxic and hypoxic culture conditions. The expression of numerous stemness-related genes was upregulated in cancer cells following the exposure to 5-FU, and remained at a high level in 5-FU-refractory cells undergoing renewal under normoxia, but decreased spontaneously under hypoxia. Imatinib downregulated the expression of stemness-related genes in cells undergoing renewal under normoxia. A combination of imatinib with PRI-2191, an analogue of 1,25-dihydroxyvitamin D₃, downregulated stemness-related genes in HCT-116/5-FU cells more efficiently than imatinib alone. A synthetic analogue of 1,25-dihydroxyvitamin D₂ (PRI-1906) abolished the effect of imatinib on gene expression in HCT-116/5-FU cells undergoing renewal under normoxia. Sunitinib promoted shift of phenotype of HT-29/5-FU cells undergoing renewal toward stem-like one. It suggests that the phenotype shift toward stemness induced by sequential sunitinib treatment following 5-FU treatment could increase a risk of cancer recurrence. In contrast to sunitinib, imatinib could be used both to interfere with cancer regrowth after conventional chemotherapy and to downregulate the expression of stemness-related genes in residual colon cancer cells capable to initiate cancer recurrence. The findings suggest that imatinib could also be combined with vitamin D analogue PRI-2191 to prevent recurrence more efficiently than imatinib alone and to compensate for vitamin D deficiency resulting from imatinib treatment.

Enrichment of genes associated with squamous differentiation in cancer initiating cells isolated from urothelial cells transformed by the environmental toxicant arsenite

Arsenic is an environmental toxicant with long-term exposure associated with the development of urothelial carcinomas. Our lab has developed an in-vitro model of urothelial carcinoma by exposing the immortal, but non-tumorigenic bladder cell line, the UROtsa, to arsenite (As³⁺). These transformed cells form tumors in immune-compromised mice, which resemble urothelial carcinomas with components of the tumor exhibiting squamous differentiation. The goal of the present study was to determine the differences in global gene expression patterns between the As³⁺-transformed UROtsa cells and the urospheres (spheroids containing putative cancer initiating cells) isolated from these cell lines and to determine if the genes involved in the development of squamous differentiation were enriched in the urospheres. The results obtained in this study show an enrichment of genes such as KRT1, KRT5, KRT6A, KRT6B, KRT6C, KRT14 and KRT16 associated with squamous differentiation, a characteristic feature seen in aggressive basal subtypes of urothelial cell carcinoma (UCC) in the urospheres isolated from As³⁺-transformed UROtsa cells. In addition, there is increased expression of several of the small proline-rich proteins (SPRR) in the urospheres and overexpression of these genes occur in UCC's displaying squamous differentiation. In conclusion, the cancer initiating cells present in the urospheres are enriched with genes associated with squamous differentiation.

Curcumin: a potent agent to reverse epithelial-to-mesenchymal transition

BACKGROUND

Epithelial-to-mesenchymal transition (EMT) is involved in tumor progression, invasion, migration and metastasis. EMT is a process by which polarized epithelial cells acquire motile mesothelial phenotypic features. This process is initiated by disassembly of cell-cell contacts through the loss of epithelial markers and replacement of these markers by mesenchymal markers. Reconstruction of the cytoskeleton and degradation of the tumor basement membrane ensures the spread of invasive malignant tumor cells to distant locations. Accumulating evidence indicates that curcumin, as a well-known phytochemical, can inhibit EMT/metastasis through various mechanisms and pathways in human tumors.

CONCLUSIONS

In this review, we summarize the mechanisms by which curcumin may affect EMT in cells under pathological conditions to understand its potential as a novel anti-tumor agent. Curcumin can exert chemo-preventive effects by inhibition and reversal of the EMT process through both TGF-β-dependent (e.g. in hepatoma and retinal pigment epithelial cancer) and -independent (e.g. in oral cancer, colorectal cancer, pancreatic cancer, hepatocellular carcinoma, breast cancer, melanoma, prostate cancer, bladder cancer, thyroid cancer and lung cancer) pathways. Curcumin can also mitigate chemoresistance through EMT suppression and promotion of the antiproliferative effects of conventional chemotherapeutics. Therefore, curcumin has the potential to be used as a novel adjunctive agent to prevent tumor metastasis, which may at least partly be attributed to its hampering of the EMT process.

GPER Mediates a Feedforward FGF2/FGFR1 Paracrine Activation Coupling CAFs to Cancer Cells toward Breast Tumor Progression

The FGF2/FGFR1 paracrine loop is involved in the cross-talk between breast cancer cells and components of the tumor stroma as cancer-associated fibroblasts (CAFs). By quantitative PCR (qPCR), western blot, immunofluorescence analysis, ELISA and ChIP assays, we demonstrated that 17β-estradiol (E2) and the G protein estrogen receptor (GPER) agonist G-1 induce the up-regulation and secretion of FGF2 via GPER together with the EGFR/ERK/c-fos/AP-1 signaling cascade in (ER)-negative primary CAFs. Evaluating the genetic alterations from METABRIC and TCGA datasets, we then assessed that FGFR1 is the most frequently amplified FGFRs family member and its amplification/expression associates with shorter survival rates in breast cancer patients. Therefore, in order to assess the functional FGF2/FGFR1 interplay between CAFs and breast cancer cells, we generated the FGFR1-knockout MDA-MB-231 cells using CRISPR/Cas9 genome editing strategy. Using conditioned medium from estrogen-stimulated CAFs, we established that the activation of FGF2/FGFR1 paracrine signaling triggers the expression of the connective tissue growth factor (CTGF), leading to the migration and invasion of MDA-MB-231 cells. Our findings shed new light on the role elicited by estrogens through GPER in the activation of the FGF2/FGFR1 signaling. Moreover, our findings may identify further biological targets that could be considered in innovative combination strategies halting breast cancer progression.

Serum CEA levels in 49 different types of cancer and noncancer diseases

Carcinoembryonic antigen (CEA) was first identified as colon cancer antigen in 1965. The higher serum CEA level than that of healthy individuals led to its clinical application as a diagnostic biomarker for colorectal cancer. Subsequent molecular biology studies revealed that CEA are glycoproteins from a family of 32 genes and are normally expressed in various tissues. Indeed, serum CEA levels are not only increased in colorectal cancer but also increased in other types of cancers and noncancer diseases. However, a systematic comparison of the serum CEA levels in different diseases has not been reported. In current study, serum CEA levels from 70,993 patients with 49 clinically defined diseases were retrieved in the clinical laboratory of Affiliated Hospital of Qingdao University over the past 5 years. In addition, serum CEA levels from 39,650 individuals who attended their annual physical examination were used as healthy controls. Based on the mean, median, and -Log₁₀p values, we found that patients suffering from 42 diseases had significantly increased serum CEA levels than that of healthy controls. Moreover, patients with lung fibrosis, pancreatic cancer, uremia, chronic obstructive pulmonary disease, colon cancer, Alzheimer's disease, rectum cancer, and lung cancer had highest media levels of serum CEA in a descending order. Furthermore, healthy individuals older than 65 years old ranked 24th out of 49 in the media levels of serum CEA. In summary, the increased serum CEA levels are associated with aging, cancers, and noncancer diseases and the molecular mechanisms behind the increased serum CEA levels in the 42 unrelated diseases need to be investigated.

Reciprocal Reprogramming of Cancer Cells and Associated Mesenchymal Stem Cells in Gastric Cancer

The interactions of cancer stem cells (CSCs) within the tumor microenvironment (TME), contribute to the overall phenomenon of intratumoral heterogeneity, which also involve CSC interactions with noncancer stromal cells. Comprehensive understanding of the tumorigenesis process requires elucidating the coordinated gene expression between cancer and tumor stromal cells for each tumor. We show that human gastric cancer cells (GSC1) subvert gene expression and cytokine production by mesenchymal stem cells (GSC-MSC), thus promoting tumor progression. Using mixed composition of human tumor xenografts, organotypic culture, and in vitro assays, we demonstrate GSC1-mediated specific reprogramming of "naïve" MSC into specialized tumor associated MSC equipped with a tumor-promoting phenotype. Although paracrine effect of GSC-MSC or primed-MSC is sufficient to enable 2D growth of GSC1, cell-cell interaction with GSC-MSC is necessary for 3D growth and in vivo tumor formation. At both the transcriptional and at the protein level, RNA-Seq and proteome analyses, respectively, revealed increased R-spondin expression in primed-MSC, and paracrine and juxtacrine mediated elevation of Lgr5 expression in GSC1, suggesting GSC-MSC-mediated support of cancer stemness in GSC1. CSC properties are sustained in vivo through the interplay between GSC1 and GSC-MSC, activating the R-spondin/Lgr5 axis and WNT/β-catenin signaling pathway. β-Catenin+ cell clusters show β-catenin nuclear localization, indicating the activation of the WNT/β-catenin signaling pathway in these cells. The β-catenin+ cluster of cells overlap the Lgr5+ cells, however, not all Lgr5+ cells express β-catenin. A predominant means to sustain the CSC contribution to tumor progression appears to be subversion of MSC in the TME by cancer cells. Stem Cells 2018 Stem Cells 2019;37:176-189.

Melatonin-mediated downregulation of ZNF746 suppresses bladder tumorigenesis mainly through inhibiting the AKT-MMP-9 signaling pathway

There still lacking effective treatment for bladder cancer. This study investigated whether melatonin (Mel) can suppress the growth and invasion of bladder cancer cells. Male C57B/L6 mice were categorized into control group (ie, subcutaneous injection of HT1197 bladder cancer cell line at the back] and treatment group [subcutaneous HT1197 cells + intraperitoneal Mel (100 mg/kg/d) from day 8 to day 21 after tumor cell injection]. In vitro Mel suppressed cell growth of four bladder cancer cell lines (ie, T24, RT4, HT1197, HT1376), cell migration in HT1197/HT1376, mitochondrial membrane potential (MMP) in T24 and colony formation in RT4 cells as well as arrested the cell cycle at G0 phase and inhibited the mitotic phase of T24 cells (all P < 0.0001). Protein expression of ZNF746 in RT4/T24 cells and protein expression phosphorylated (p)-AKT/MMP-2/MMP-9 in HT1197/HT1376 cells were reduced following Mel treatment (all P < 0.001). Transfection of T24 cells with plasmid-based shRNA (ie, ZNF746-silencing) downregulated the protein expression of MMP-9, cell growth, and invasion and attachment to endothelial cells but upregulated the colony formation (all P < 0.001). Mel suppressed oxidative stress and MMP but upregulated mitochondria mass in ZNF746-silenced T24 cells, whereas these parameters exhibited a similar patter to Mel treatment in ZNF746-silenced T24 cells (all P < 0.0001). In vivo study demonstrated that Mel treatment significantly suppressed cellular expressions of MMP-9/MMP-2, protein expressions of ZNF746/p-AKT, and tumor size (all P < 0.001). Mel treatment suppressed the growth, migration, and invasion of bladder carcinoma cells through downregulating ZNF746-regulated MMP-9/MMP-2 signaling.