Overexpression of HepaCAM inhibits cell viability and motility through suppressing nucleus translocation of androgen receptor and ERK signaling in prostate cancer

HepaCAM‑PIK3CA axis regulates the reprogramming of glutamine metabolism to inhibit prostate cancer cell proliferation

Energy metabolism reprogramming is becoming an increasingly important hallmark of cancer. Specifically, cancers tend to undergo metabolic reprogramming to upregulate a cell-dependent glutamine (Gln) metabolism. Notably, hepatocellular cell adhesion molecule (HepaCAM) has been previously reported to serve a key role as a tumour suppressor. However, the possible regulatory role of HepaCAM in Gln metabolism in prostate cancer (PCa) remains poorly understood. In the present study, bioinformatics analysis predicted a significant negative correlation among the expression of HepaCAM, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA), glutaminase (GLS) and solute carrier family 1 member 5 (SLC1A5), components of Gln metabolism, in clinical and genomic datasets. Immunohistochemistry results verified a negative correlation between HepaCAM and PIK3CA expression in PCa tissues. Subsequently, liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) assays were performed, and the results revealed markedly reduced levels of Gln and metabolic flux in the blood samples of patients with PCa and in PCa cells. Mechanistically, overexpression of HepaCAM inhibited Gln metabolism and proliferation by regulating PIK3CA in PCa cells. In addition, Gln metabolism was discovered to be stress-resistant in PCa cells, since the expression levels of GLS and SLC1A5 remained high for a period of time after Gln starvation. However, overexpression of HepaCAM reversed this resistance to some extent. Additionally, alpelisib, a specific inhibitor of PIK3CA, effectively potentiated the inhibitory effects of HepaCAM overexpression on Gln metabolism and cell proliferation through mass spectrometry and CCK-8 experiments. In addition, the inhibitory effect of PIK3CA on the growth of tumor tissue in nude mice was also confirmed by immunohistochemistry in vivo. To conclude, the results from the present study revealed an abnormal Gln metabolic profile in the blood samples of patients with PCa, suggesting that it can be applied as a clinical diagnostic tool for PCa. Additionally, a key role of the HepaCAM/PIK3CA axis in regulating Gln metabolism, cell proliferation and tumour growth was identified. The combination of alpelisib treatment with the upregulation of HepaCAM expression may serve as a novel method for treating patients with PCa.

Panobinostat reverses HepaCAM gene expression and suppresses proliferation by increasing histone acetylation in prostate cancer

Increased expression of histone deacetylases (HDACs) affiliated to the epigenetic regulation is common aberration in prostate cancer (PCa). We have confirmed that hepatocyte cell adhesion molecule (hepaCAM), acting as a tumor suppressor gene, is rarely expressed in PCa previously, However, the mechanisms of which is still unknown. The level of histone acetylation reportedly may involve anti-oncogene transcription and expression. In this study, we investigated the effect of panobinostat, the broad-spectrum histone deacetylases inhibitor, on PCa LNCaP and DU145 cell growth, and observed re-expression of hepaCAM when treated with panobinostat. We demonstrated that intranuclear acetylation of lys9 of histone H3 (Ac-H3K9) were increased, while that of both mRNA and protein of HDAC1, HDAC3, and HDAC4 were decreased when the treating concentration of panobinostat increased. We confirmed the relationship between histone acetylation and the expression of hepaCAM and AR in prostate cancer tissues. We also confirmed that panobinostat could overcome the resistance for androgen deprivation therapy (ADT). Further, we combined panobinostat with Ad-hepaCAM, which resulted in significantly increased antitumor activity and significant attenuation of the proliferation-associated genes CCND1 and PCNA compared to each single treatment. In conclusion, panobinostat may enhance the acetylation of lys9 of histone 3 and reverse the hepaCAM expression through its inhibitory effect on HDACs activity in PCa LNCaP and DU145 cells; Ad-hepaCAM combined with panobinostat may synergistically inhibit the growth of LNCaP and DU145 cells, via a potential mechanism associated with the down-regulation of the expression of CCND1 and PCNA. These findings suggest that this therapeutic strategy should be further developed in clinical trials.

STAT3 phosphorylation is required for the HepaCAM-mediated inhibition of castration-resistant prostate cancer cell viability and metastasis

BACKGROUND

Castration-resistant prostate cancer (CRPC) is an advanced disease that is difficult to treat, the mechanism of it is unclear. This study illustrated the function of hepatocyte cell adhesion molecule (HepaCAM) on CRPC cell viability and metastasis.

METHODS

The expression of HepaCAM and p-STAT3 in CRPC tissues were determined by immunohistochemistry and western blot analysis. Cell Counting Kit-8 and colony formation assays were deployed to analyze the growth ability of CRPC cells following the adenovirus-mediated re-expression of HepaCAM. CRPC cell migration and invasion capacity were investigated by wound healing and Matrigel-coated transwell assays, respectively. The messenger RNA or protein levels of p-STAT3, CyclinD1, cMyc, MMP2, MMP9, and VEGF were determined by reverse transcription (RT) followed by quantitative real-time polymerase chain reaction (RT-qPCR), and western blot analysis after either HepaCAM re-expression alone or in combination with IL-22 treatment. A CRPC orthotopic xenograft mouse model was applied to investigate the functional effect of HepaCAM on the metastasis of CRPC cells to the lungs.

RESULTS

The expression levels of HepaCAM were decreased while those of p-STAT3 were elevated in CRPC cells compare with surrounding benign tissues (p < .001). The overexpression of HepaCAM in CRPC cells notably reduced proliferation, migration, and invasion by inhibiting the expression of p-STAT3, CyclinD1, cMyc, MMP2, MMP9, and VEGF (p < .05). In addition, the expression of HepaCAM significantly inhibited the IL-22/p-STAT3 axis and the metastasis of CRPC cells to the lungs.

CONCLUSIONS

Our data suggested that HepaCAM suppressed the viability of CRPC cells via the IL-22/p-STAT3 axis and inhibited the metastasis of CRPC cells from the prostate to the lungs (p < .05).

Novel Gene Signatures Predictive of Patient Recurrence-Free Survival and Castration Resistance in Prostate Cancer

Simple Summary

Molecular signatures predictive of recurrence-free survival (RFS) and castration resistance are critical for treatment decision-making in prostate cancer (PCa), but the robustness of current signatures is limited. This study aims to identify castration-resistant PCa (CRPC)-associated genes and develop robust RFS and CRPC signatures. Among 287 genes differentially expressed between localized CRPC and hormone-sensitive PCa (HSPC) samples, 6 genes constituted a signature (CRPC-derived prognosis signature, CRPCPS) that predicted RFS. Moreover, a 3-gene panel derived from the 6 CRPCPS genes was capable of distinguishing CRPC from HSPC. The CRPCPS predicted RFS in 5/9 cohorts in the multivariate analysis and maintained prognostic in patients stratified by tumor stage, Gleason score, and lymph node metastasis status. It also predicted overall survival and metastasis-free survival. Notably, the signature was validated in another six independent cohorts. These findings suggest that these two signatures could be robust tools for predicting RFS and CRPC in clinical practice.

Abstract

Molecular signatures predictive of recurrence-free survival (RFS) and castration resistance are critical for treatment decision-making in prostate cancer (PCa), but the robustness of current signatures is limited. Here, we applied the Robust Rank Aggregation (RRA) method to PCa transcriptome profiles and identified 287 genes differentially expressed between localized castration-resistant PCa (CRPC) and hormone-sensitive PCa (HSPC). Least absolute shrinkage and selection operator (LASSO) and stepwise Cox regression analyses of the 287 genes developed a 6-gene signature predictive of RFS in PCa. This signature included NPEPL1, VWF, LMO7, ALDH2, NUAK1, and TPT1, and was named CRPC-derived prognosis signature (CRPCPS). Interestingly, three of these 6 genes constituted another signature capable of distinguishing CRPC from HSPC. The CRPCPS predicted RFS in 5/9 cohorts in the multivariate analysis and remained valid in patients stratified by tumor stage, Gleason score, and lymph node status. The signature also predicted overall survival and metastasis-free survival. The signature’s robustness was demonstrated by the C-index (0.55–0.74) and the calibration plot in all nine cohorts and the 3-, 5-, and 8-year area under the receiver operating characteristic curve (0.67–0.77) in three cohorts. The nomogram analyses demonstrated CRPCPS’ clinical applicability. The CRPCPS thus appears useful for RFS prediction in PCa.

Long noncoding RNA HOTAIR regulates the invasion and metastasis of prostate cancer by targeting hepaCAM

Background

The role of HOX transcript antisense RNA (HOTAIR) has been proven to be important in tumorigenesis. However, how this molecule promotes metastasis and invasion in PCa is still unclear.

Methods

The relationship between HOTAIR and hepatocellular adhesion molecule (hepaCAM) in PCa was identified by immunohistochemistry, immunofluorescence, plasmid transfection, quantitative real-time PCR and immunoblotting. The regulatory effects of HOTAIR on hepaCAM and MAPK signalling and their key roles in PCa metastasis were investigated in vitro.

Results

The expression of HOTAIR was inversely correlated with hepaCAM in the blood and tissue of PCa patients. Here, hepaCAM was identified as a novel target gene of HOTAIR and was critical for the invasiveness of PCa. HOTAIR recruited PRC2 to the hepaCAM promoter, resulting in high levels of H3K27me3 and the absence of hepaCAM with an abnormally activated MAPK pathway. Both HOTAIR depletion and EZH2 inhibition could induce hepaCAM re-expression with inhibitory MAPK signalling and decrease the invasive and metastatic capabilities of PCa cells.

Conclusions

This study demonstrates that HOTAIR promotes invasion and metastasis of PCa by decreasing the inhibitory effect of hepaCAM on MAPK signalling. Therefore, the HOTAIR/hepaCAM/MAPK axis may provide a new avenue towards therapeutic strategies and prognostic indicators for advanced prostate cancer.

Sub-lethal Doses of Polybrominated Diphenyl Ethers, in Vitro, Promote Oxidative Stress and Modulate Molecular Markers Related to Cell Cycle, Antioxidant Balance and Cellular Energy Management

In the present study, we evaluated the effects of different concentrations of the polybrominated diphenyl ethers (PBDEs) BDE-209, BDE-47 and BDE-99, on the vitality and oxidative stress of a HS-68 human cell culture exposed to the compounds for three days. The results showed that for this exposure time, only the highest concentrations produced a significant vitality reduction and oxidative stress induction (p < 0.05), measured as reactive oxygen species (ROS). Subsequently, in order to verify the effects of sub-lethal doses, cells were exposed for a longer time and data collected, after 12 and 20 days, to study ROS production and some molecular markers related to cell cycle and stress (p53, pRB, PARP, c-Jun and c-Fos), antioxidant status and proliferation (ERK, c-Jun and c-Fos), energy balance (NRF2, AMPK, HIF). Most of the biomarkers were influenced by the treatments, indicating that sub-lethal doses of PBDEs, for longer time, can enhance the production of ROS, altering the energetic metabolism, cell cycle and antioxidant balance, determining possible negative effects on the cell proliferation equilibrium.

HepaCAM inhibits cell proliferation and invasion in prostate cancer by suppressing nuclear translocation of the androgen receptor via its cytoplasmic domain

Hepatocyte cell adhesion molecule (HepaCAM) is a tumour suppressor. However, the mechanism of HepaCAM function in prostate cancer (PCa) remains unknown. In the present study, HepaCAM, androgen receptor (AR) and Ran were analysed in 46 PCa tissue samples using immunohistochemistry. Subsequently, the influence of HepaCAM and its cytoplasmic domain on cell proliferation, migration, and invasion, and associated proteins was examined using MTT, wound healing, Transwell and western blotting assays, respectively. Furthermore, nuclear translocation of AR and Ran was analysed using immunofluorescence and Western blot assays. The results demonstrated that HepaCAM expression was reduced in PCa, and there was an association between downregulation of HepaCAM and changes in the distribution of AR and Ran. Furthermore, HepaCAM, specifically the cytoplasmic domain, was involved in cell proliferation, migration and invasion. Nuclear translocation of AR was dependent on HepaCAM and its cytoplasmic domain. Additionally, HepaCAM suppression of the nuclear translocation of AR occurred via Ran. The results suggest that HepaCAM and its cytoplasmic domain suppress the nuclear translocation of AR via Ran in PCa. The cytoplasmic domain of HepaCAM may serve as a novel target for therapy in PCa.

HepaCAM Regulates Warburg Effect of Renal Cell Carcinoma via HIF-1α/NF-κB Signaling Pathway

OBJECTIVE

To investigate how hepatocyte cell adhesion molecule (hepaCAM) regulates cancer energy metabolism through hypoxia-inducible factor (HIF-1α) in renal cell carcinoma (RCC).

MATERIALS AND METHODS

The expression of hepaCAM and HIF-1α in RCC tissue samples was examined by immunohistochemistry. Glucose consumption and lactate production assays were used to detect metabolic activity in RCC cell lines. P65 and IκB kinase (IKKβ) mRNA and protein expression were detected using quantitative real-time polymerase chain reaction and western blotting, respectively. Nuclear translocation of P65 was observed by immunofluorescence staining after re-expressing hepaCAM. The luciferase reporter assay was applied to validate the transcriptional activity of HIF-1α.

RESULTS

HIF-1α expression was elevated and hepaCAM suppressed in RCC compared with adjacent normal tissues. Furthermore, hepaCAM re-expression significantly decreased glycolytic metabolism in RCC cell lines, and reduced HIF-1α, IKKβ, and P65 expression. The expression of HIF-1α, GLUT1, LDHA, and PKM2 were further reduced with combined hepaCAM overexpression and treatment with the NF-κB inhibitor BAY11-7082, compared to hepaCAM overexpression alone. Additionally, hepaCAM decreased the transcriptional activity of HIF-1α and blocked P65 nuclear translocation by the NF-κB pathway.

CONCLUSION

Our data suggest that hepaCAM suppresses the Warburg effect via the HIF-1α/NF-κB pathway in RCC, which is a facilitating factor in hepaCAM-reduced tumorigenesis.

Erianin inhibits human cervical cancer cell through regulation of tumor protein p53 via the extracellular signal-regulated kinase signaling pathway

Erianin, a natural bibenzyl compound, is present in Dendrobium chrysotoxum Lindl. (commonly known as Shihu in China), which is used as an antipyretic and analgesic in traditional Chinese medicine, and has been reported to exert inhibitory effects on cancer cells in vitro. Cervical cancer is the third-most common cancer in women worldwide, and has the highest morbidity rate of gynecological malignancies. Thus, the identification of effective chemotherapeutical agents to treat this disease is urgent. The aim of the present study was to elucidate the biological functions and molecular mechanism of erianin on HeLa cells. Cellular proliferation was assessed using an MTT assay and flow cytometry assay with propidium iodide (PI) staining. Apoptosis rates were observed using a high content screening system via annexin V-fluorescein isothiocyanate/PI double staining, and measured by flow cytometry. The protein levels of tumor protein p53, extracellular signal-regulated kinase 1/2 (ERK1/2), caspase-3, B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X (Bax) were assessed by western blot analysis. Erianin inhibited the growth of HeLa cells and induced apoptosis in a dose- and time-dependent manner, inducing cell cycle arrest at the G₂/M stage. Erianin treatment also increased the expression of Bax and caspase-3, but decreased levels of Bcl-2 and phosphorylated-ERK1/2. Cells treated with paclitaxel were regarded as the positive group. Together, the results of the present study indicated that erianin could be considered as an effective drug candidate; in HeLa cells it inhibited cellular proliferation and promoted apoptosis via regulation of the ERK1/2 signaling and mitochondrial-based apoptosis pathways. Thus, erianin has the promise to be developed further for cervical cancer therapy.

HepaCAM inhibits the malignant behavior of castration-resistant prostate cancer cells by downregulating Notch signaling and PF-3084014 (a γ-secretase inhibitor) partly reverses the resistance of refractory prostate cancer to docetaxel and enzalutamide in vitro

Castration-resistant prostate cancer (CRPC) continues to be a major challenge in the treatment of prostate cancer (PCa). The expression of hepatocyte cell adhesion molecule (HepaCAM), a novel tumor suppressor, is frequently downregulated or lost in PCa. Overactivated Notch signaling is involved in the development and progression of PCa, including CRPC. In this study, we found that the activities of Notch signaling were elevated, while HepaCAM expression was decreased in CRPC tissues compared with matched primary prostate cancer (PPC) tissues. In addition, HepaCAM negativity was found to be associated with a worse progression-free survival (PFS). Furthermore, the overexpression of HepaCAM induced by transfection with a HepaCAM overexpression vector (Ad-HepaCAM) exerted antitumor effects by decreasing the proliferation, and suppressing the invasion and migration of bicalutamide-resistant (Bica-R) cells and enzalutamide-resistant (Enza-R) cells. Importantly, we found that the antitumor effects of HepaCAM on the resistant cells were associated with the downregulation of Notch signaling. Moreover, we revealed that PF-3084014 (a γ-secretase inhibitor) re-sensitized Enza-R cells to enzalutamide, and sequential dual-resistant (E+D-R) cells to docetaxel. Additionally, the findings of this study demonstrated that the use of PF-3084014 alone exerted potent antitumor effect on the resistant cells in vitro. On the whole, this study indicates that HepaCAM potentially represents a therapeutic target and PF-3084014 may prove to a promising agent for use in the treatment of refractory PCa.

TRIM36, a novel androgen-responsive gene, enhances anti-androgen efficacy against prostate cancer by inhibiting MAPK/ERK signaling pathways

Hormone therapy drugs, such as bicalutamide and enzalutamide, directed against prostate cancer focus on androgen receptor (AR) signaling and are initially effective, but the disease progresses to lethality as resistance to these drugs develops. A method to prolong the drug response time and improve the drug efficacy is still unavailable. TRIM36 was reported as a novel androgen signaling target gene and is upregulated in prostate cancer. In this study, we found that 63.4% (64/95) of PCa in TMA expressed the TRIM36 protein. Interestingly, patients with negative TRIM36 expression had a shorter biochemical recurrence-free survival. TRIM36 expression was significantly associated with the Gleason score (P = 0.005), delayed prostate cancer cell cycle progression and inhibited cell proliferation in vitro and in vivo, and these effects were mediated via inhibition of the MAPK/ERK phosphorylation pathway. Remarkably, we found that rescuing the expression of TRIM36 during anti-androgen therapy could improve the drug efficacy. Collectively, TRIM36 is a novel androgen-responsive gene, and it dramatically enhanced the efficacy of anti-androgen drugs against prostate cancer.

Role of androgen receptor on cyclic mechanical stretch-regulated proliferation of C2C12 myoblasts and its upstream signals: IGF-1-mediated PI3K/Akt and MAPKs pathways

OBJECTS

To detect the effects of androgen receptor (AR) on cyclic mechanical stretch-modulated proliferation of C2C12 myoblasts and its pathways: roles of IGF-1, PI3K and MAPK.

METHODS

C2C12 were randomly divided into five groups: un-stretched control, six or 8 h of fifteen percent stretch, and six or 8 h of twenty percent stretch. Cyclic mechanical stretch of C2C12 were completed using a computer-controlled FlexCell Strain Unit. Cell proliferation and IGF-1 concentration in medium were detected by CCK8 and ELISA, respectively. Expressions of AR and IGF-1R, and expressions and activities of PI3K, p38 and ERK1/2 in stretched C2C12 cells were determined by Western blot.

RESULTS

①The proliferation of C2C12 cells, IGF-1 concentration in medium, expressions of AR and IGF-1R, and activities of PI3K, p38 and ERK1/2 were increased by 6 h of fifteen percent stretch, while decreased by twenty percent stretch for six or 8 h ②The fifteen percent stretch-increased proliferation of C2C12 cells was reversed by AR inhibitor, Flutamide. ③The increases of AR expression, activities of PI3K, p38 and ERK1/2 resulted from fifteen percent stretch were attenuated by IGF-1 neutralizing antibody, while twenty percent stretch-induced decreases of the above indicators were enhanced by recombinant IGF-1. ④Specific inhibitors of p38, ERK1/2 and PI3K all decreased the expression of AR in fifteen percent and twenty percent of stretched C2C12 cells.

CONCLUSIONS

Cyclic mechanical stretch modulated the proliferation of C2C12 cells, which may be attributed to the alterations of AR via IGF-1-PI3K/Akt and IGF-1-MAPK (p38, ERK1/2) pathways in C2C12 cells.

Interleukin 6 induces cell proliferation of clear cell renal cell carcinoma by suppressing hepaCAM via the STAT3-dependent up-regulation of DNMT1 or DNMT3b

Interleukin 6 (IL-6), a tumor promoting cytokine, has been largely implicated in the development of renal cell carcinoma (RCC). Hepatocyte cell adhesion molecule (hepaCAM) is a novel tumor suppressor, which is lost or down-regulated in many cancer types including RCC. In the present study, we intensively investigated the connection between IL-6 and hepaCAM in RCC. Our analysis of RCC tissues, adjacent tissues and paired serum samples from RCC patients revealed that IL-6 was elevated in patient serum and RCC tissue, whereas hepaCAM was completely lost or significantly down-regulated. Furthermore, we observed an association between IL-6 increase and hepaCAM decrease in RCC tissue samples. In the section of cytological researches, we found in RCC cell lines that IL-6 was a direct upstream regulator of hepaCAM, and that hepaCAM down-regulation was involved in IL-6-driven cell proliferation. We also demonstrated that IL-6-mediated promoter hypermethylation largely accounted for the hepaCAM loss in RCC, and it was STAT3-dependent. Additionally, our data showed that DNMT1 up-regulation induced by IL-6/STAT3 signaling was indispensable for IL-6-mediated hepaCAM loss in RCC cell lines ACHN and 769-P, while DNMT3b up-regulation was crucial for hepaCAM loss in A498. Our findings provide a novel signal pathway regulating cell proliferation, potentially representing a therapeutic target for RCC.

Overexpression of HepaCAM inhibits bladder cancer cell proliferation and viability through the AKT/FoxO pathway

PURPOSE

HepaCAM, an N-linked glycoprotein that encodes a member of the immunoglobulin superfamily, has been reported to be a tumor suppressor gene that mediates diverse cellular bio-functions. Recent studies have shown that the FoxO transcription factors play a pivotal role during cancer progression. Here, we explored the correlation between HepaCAM and the FoxO family via regulation of the PI3K/AKT pathway.

METHODS

HepaCAM and FoxO3 expression were detected by immunohistochemistry staining. We detected the effect of HepaCAM on the proliferation and viability of bladder cancer through AKT signaling by colony formation, the MTT assay and Western blotting. We observed the nuclear translocation of FoxO3 by immunofluorescence staining after expressing HepaCAM.

RESULTS

HepaCAM depletion was discovered in bladder cancer tissues compared with adjacent normal tissues, and the decreased level was associated with the degradation of FoxO3. Furthermore, re-expression of HepaCAM significantly disrupted T24 and BIU-87 cell colony formation, as well as reduced p-AKT and p-FoxO protein expression. We found that the combined treatment of HepaCAM-overexpressing adenovirus with the PI3K inhibitor LY294002 enhanced the inhibitory effects on cell proliferation, viability and protein expression. Additionally, overexpressed HepaCAM decreased the activated effect on cell proliferation, viability and protein expression of the AKT activator SC79. Moreover, we observed that HepaCAM induced nuclear translocation of FoxO3.

CONCLUSIONS

Our research implicated that HepaCAM may function as a novel therapeutic target that inhibits the proliferation of bladder cancer via the AKT/FoxO pathway.

Overexpression of CXCL3 can enhance the oncogenic potential of prostate cancer

PURPOSE

CXCL3 and its receptor CXCR2 were considered to play particularly important roles in the progression of malignancies. However, the investigations about CXCL3/CXCR2 axis in prostate cancer have been poorly involved. Herein we firstly reported our studies on the expression and biological roles of CXCL3 and CXCR2 in prostate cancer.

METHODS

Expression levels of CXCL3 and CXCR2 in prostate cancer cell lines (PC-3, DU145 and LNCaP), immortalized prostate stromal cell line (WPMY-1) and immortalized prostate epithelial cell line (RWPE-1) were investigated by RT-PCR, ELISA and western blot, whereas expression levels of CXCL3 in a prostate tissue microarray were detected by immunohistochemistry. Cell counting kit-8 and transwell assays were, respectively, utilized to determine the effects of exogenous CXCL3 on the cell proliferation and migration. We further examined whether CXCL3 could regulate the expression of genes correlated with prostate tumorigenesis by RT- PCR.

RESULTS

Elevated expression of CXCR2 was detected in DU145, LNCaP and RWPE-1. Moreover, high-level CXCL3 can be secreted by PC-3 and RWPE-1, and CXCL3 protein expression level in tissue microarray is concordant with prostate cancer metastasis. Exogenous CXCL3 does not contribute to proliferation, but has a significant effect on migration of prostate cancer cells and RWPE-1. Finally, our data showed that exogenous CXCL3 can regulate the expression of genes including ERK, TP73, NUMB, BAX and NDRG3.

CONCLUSION

Our findings suggest that CXCL3 and its receptor CXCR2 are overexpressed in prostate cancer cells, prostate epithelial cells and prostate cancer tissues, which may play multiple roles in prostate cancer progression and metastasis.

Circuits of cancer drivers revealed by convergent misregulation of transcription factor targets across tumor types

BACKGROUND

Large tumor genome sequencing projects have now uncovered a few hundred genes involved in the onset of tumorigenesis, or drivers, in some two dozen malignancies. One of the main challenges emerging from this catalog of drivers is how to make sense of their heterogeneity in most cancer types. This is key not only to understand how carcinogenesis appears and develops in these malignancies to be able to early diagnose them, but also to open up the possibility to employ therapeutic strategies targeting a driver protein to counteract the alteration of another connected driver.

METHODS

Here, I focus on driver transcription factors and their connection to tumorigensis in several tumor types through the alteration of the expression of their targets. First, I explore their involvement in tumorigenesis as mutational drivers in 28 different tumor types. Then, I collect a list of downstream targets of the all driver transcription factors (TFs), and identify which of them exhibit a differential expression upon alterations of driver transcription factors.

RESULTS

I identify the subset of targets of each TF most likely mediating the tumorigenic effect of their driver alterations in each tumor type, and explore their overlap. Furthermore, I am able to identify other driver genes that cause tumorigenesis through the alteration of very similar sets of targets.

CONCLUSIONS

I thus uncover these circuits of connected drivers which cause tumorigenesis through the perturbation of overlapping cellular pathways in a pan-cancer manner across 15 malignancies. The systematic detection of these circuits may be key to propose novel therapeutic strategies indirectly targeting driver alterations in tumors.

HEPACAM inhibited the growth and migration of cancer cells in the progression of non-small cell lung cancer

Hepatocyte cell adhesion molecule (HEPACAM), a member of immunoglobulin superfamily, is an adhesion molecule. Although dysregulation of several adhesion molecules has been implicated in the progression of non-small cell lung cancer (NSCLC), the expression profile and functions of HEPACAM in NSCLC remains unknown. In this study, it was found that the expression of HEPACAM was downregulated in NSCLC tissues. Forced expression of HEPACAM in NSCLC cells inhibited the growth and migration of the cancer cells, while knocking down the expression of HEPACAM promoted cell growth, migration, and metastasis. In the molecular mechanism study, HEPACAM was found to be a negative regulator of beta-catenin/TCF signaling. Taken together, this study revealed the suppressive roles of HEPACAM in NSCLC and restoring the function of HEPACAM in NSCLC might be a promising strategy for the therapy.

Overview on the complexity of androgen receptor-targeted therapy for prostate cancer

In the past decades, the field of prostate cancer (PCa) biology has developed exponentially and paralleled with that has been the growing interest in translation of laboratory findings into clinical practice. Based on overwhelming evidence of high impact research findings which support the underlying cause of insufficient drug efficacy in patients progressing on standard androgen deprivation therapy (ADT) is due to persistent activation of the androgen receptor (AR) signaling axis. Therefore, newer agents must be discovered especially because newer ADT such as abiraterone and enzalutamide are becoming ineffective due to rapid development of resistance to these agents. High-throughput technologies are generating massive and highly dimensional genetic variation data that has helped in developing a better understanding of the dynamic repertoire of AR and AR variants. Full length AR protein and its variants modulate a sophisticated regulatory system to orchestrate cellular responses. We partition this multicomponent review into subsections addressing the underlying mechanisms of resistance to recent therapeutics, positive and negative regulators of AR signaling cascade, and how SUMOylation modulates AR induced transcriptional activity. Experimentally verified findings obtained from cell culture and preclinical studies focusing on the potential of natural agents in inhibiting mRNA/protein levels of AR, nuclear accumulation and enhanced nuclear export of AR are also discussed. We also provide spotlight on molecular basis of enzalutamide resistance with an overview of the strategies opted to overcome such resistance. AR variants are comprehensively described and different mechanisms that regulate AR variant expression are also discussed. Reconceptualization of phenotype- and genotype-driven studies have convincingly revealed that drug induced resistance is a major stumbling block in standardization of therapy. Therefore, we summarize succinctly the knowledge of drug resistance especially to ADT and potential avenues to overcome such resistance for improving the treatment outcome of PCa patients.

ERK1/2 promoted proliferation and inhibited apoptosis of human cervical cancer cells and regulated the expression of c-Fos and c-Jun proteins

Small-molecule inhibitors targeted MAPK have been wildly used for some cancer therapeutics as a biologically viable model, but no one has been used for cervical caner. ERK1/2, one of MAPK kinases, is expressed high in cervical cancer tissue. The aim of the present study was to evaluate the effects of ERK1/2 inhibitor U0126 on proliferation and apoptosis of cervical cancer cells and appraise the correlated mechanism of the effects. In this study, the cell proliferation of Hela and C33A cervical cancer cells was tested by Cell Counting Kit-8 (CCK8) assay and cell counting after treated with ERK1/2 inhibitor U0126. The cell cycle and apoptosis were evaluated by flow cytometry (FCM). The protein levels of ERK1/2 and c-Fos and c-Jun were detected by Western blot. The results indicated that after down-regulating ERK1/2 proteins with the inhibitor U0126, Hela and C33A cells proliferation was inhibited, cell apoptosis was promoted, the proportions of G0/G1 stage in cell cycle increased, and G2/M stages decreased. After down-regulating ERK1/2 proteins of Hela and C33A cells, the expression levels of p-c-Fos protein decreased, while p-c-Jun protein increased. The results of this study indicated that ERK1/2 may promote the development of cervical cancer cells, suggesting ERK1/2 inhibitor may be used as an effective target for cervical cancer therapies working for. It might inhibit cervical cancer cells growth via regulating the transcription factors expression of c-Fos and c-Jun.