Misdiagnosed gastric diverticulum as a left adrenal lesion on imaging.

Key Clinical Message: Gastric diverticulum in the posterior wall of the stomach is very rare, and it is easy to be misdiagnosed as a left adrenal mass on imaging. Therefore, we must consider the possibility of gastric diverticulum when diagnosing a left adrenal mass. Abstract: This paper reports a case of gastric diverticulum that was misdiagnosed as a left adrenal mass on abdominal enhanced CT. The patient underwent laparoscopic adrenalectomy, but there was no mass in the left adrenal found during surgery. After the incision of the retroperitoneum, a cystic mass was found adjacent to the posterior gastric wall which turned out to be gastric diverticulum. This case suggests that gastric diverticulum, a rare disease, may be interpreted as an adrenal mass on imaging. Therefore, as a urologist, the gastric diverticulum must be excluded when CT suggests a mass in the left adrenal region.

Enhancer RNA promotes resistance to radiotherapy in bone-metastatic prostate cancer by m6A modification.

Rationale: Prostate cancer metastasizes to the bone with the highest frequency and exhibits high resistance to 177Lu-prostate-specific membrane antigen (PSMA) radioligand therapy. Little is known about bone metastatic prostate cancer (mPCa) resistance to radiation. Methods: We filtered the metastatic eRNA using RNA-seq, MeRIP-seq, RT-qPCR and bioinformation. Western blot, RT-qPCR, CLIP, co-IP and RNA pull-down assays were used for RNA/protein interaction, RNA or protein expression examination. MTS assay was used to determine cell viability in vitro, xenograft assay was used to examine the tumor growth in mice. Results: In this study, we screened and identified bone-specific N6 adenosine methylation (m6A) on enhancer RNA (eRNA) that played a post-transcriptional functional role in bone mPCa and was correlated with radiotherapy (RT) resistance. Further data demonstrated that RNA-binding protein KHSRP recognized both m6A at eRNA and m6Am at 5'-UTR of mRNA to block RNA degradation from exoribonuclease XRN2. Depletion of the MLXIPe/KHSRP/PSMD9 regulatory complex inhibited tumor growth and RT sensitization of bone mPCa xenograft in vitro and in vivo. Conclusions: Our findings indicate that a bone-specific m6A-modified eRNA plays a vital role in regulating mPCa progression and RT resistance and might be a novel specific predictor for cancer RT.

Downregulation of SHMT2 promotes the prostate cancer proliferation and metastasis by inducing epithelial-mesenchymal transition.

Serine hydroxymethyltransferase 2 (SHMT2) is a key enzyme that regulates serine/glycine transition; however, its specific function and molecular mechanisms in tumors remain controversial. In this study, we aimed to enhance the understanding in this regard. Through in vitro and in vivo experiments, as well as data analyses using public databases, we investigated the effect of SHMT2 in prostate cancer. Our results indicated that SHMT2 acts as a prostate cancer tumor proliferation suppressor and negatively regulates the aggressive behavior of prostate cancer through activation of epithelial-mesenchymal transition. Additionally, downregulated SHMT2 expression was observed in more advanced prostate cancer phenotypes, and further analysis showed that its depletion promoted proliferation and migration in prostate cancer cell lines. Taken together, our results revealed the function of SHMT2 in prostate cancer and may potentially play a role in the exploration of new therapeutic strategies.

Functional roles of antisense enhancer RNA for promoting prostate cancer progression.

Rationale: Enhancer RNA (eRNA) bi-directionally expresses from enhancer region and sense eRNA regulates adjacent mRNA in cis and in trans. However, it has remained unclear whether antisense eRNAs in different direction are functional or merely a reflection of enhancer activation. Methods: Strand-specific, ribosome-minus RNA sequencing (RNA-seq) were performed in AR positive prostate cancer cells. RNA-seq, GRO-seq, ChIP-seq, 4C-seq and DNA-methylation-seq that published in our and other labs were re-analyzed to define bi-directional enhancer RNA and DNA methylation regions. Molecular mechanisms were demonstrated by 3C, ChIP, ChIRP, CLIP, RT-PCR and western blot assays. The biological functions of antisense-eRNA were assessed using mice xenograft model and RT-PCR analysis in human tissues. Results: In this study, we identified that antisense eRNA was regulated by androgen receptor (AR) activity in prostate cancer cells. Antisense eRNA negatively regulated antisense ncRNA in AR-related target genes' loci, through recruiting DNMT1 on the antisense enhancer in the gene-ending regions and elevating DNA methylation. Importantly, the chromatin exhibited a double looping manner that facilitated sense-eRNA to promoter and antisense-eRNA to gene-ending region in cis. Depletion of antisense eRNA impaired its neighbor mRNA expression, cancer growth and invasion. The expressions of antisense eRNA were correlated with biochemical recurrence and clinical marker PSA's levels in patients' tissues. Conclusions: The findings indicated that antisense eRNA was a functional RNA and may be a novel target that when suppressed improved prostate cancer therapy and diagnosis. New chromatin interaction among enhancer, promoter and gene-ending region might provide new insight into the spatiotemporal mechanism of the gene transcription and acting of bi-directional eRNAs.

Intrinsic BET inhibitor resistance in SPOP-mutated prostate cancer is mediated by BET protein stabilization and AKT-mTORC1 activation.

Bromodomain and extraterminal domain (BET) protein inhibitors are emerging as promising anticancer therapies. The gene encoding the E3 ubiquitin ligase substrate-binding adaptor speckle-type POZ protein (SPOP) is the most frequently mutated in primary prostate cancer. Here we demonstrate that wild-type SPOP binds to and induces ubiquitination and proteasomal degradation of BET proteins (BRD2, BRD3 and BRD4) by recognizing a degron motif common among them. In contrast, prostate cancer-associated SPOP mutants show impaired binding to BET proteins, resulting in decreased proteasomal degradation and accumulation of these proteins in prostate cancer cell lines and patient specimens and causing resistance to BET inhibitors. Transcriptome and BRD4 cistrome analyses reveal enhanced expression of the GTPase RAC1 and cholesterol-biosynthesis-associated genes together with activation of AKT-mTORC1 signaling as a consequence of BRD4 stabilization. Our data show that resistance to BET inhibitors in SPOP-mutant prostate cancer can be overcome by combination with AKT inhibitors and further support the evaluation of SPOP mutations as biomarkers to guide BET-inhibitor-oriented therapy in patients with prostate cancer.

AKT-phosphorylated FOXO1 suppresses ERK activation and chemoresistance by disrupting IQGAP1-MAPK interaction.

Nuclear FOXO proteins act as tumor suppressors by transcriptionally activating genes involved in apoptosis and cell cycle arrest, and these anticancer functions are inhibited by AKT-induced phosphorylation and cytoplasmic sequestration of FOXOs. We found that, after AKT-mediated phosphorylation at serine 319, FOXO1 binds to IQGAP1, a hub for activation of the MAPK pathway, and impedes IQGAP1-dependent phosphorylation of ERK1/2 (pERK1/2). Conversely, decreased FOXO1 expression increases pERK1/2 in cancer cell lines and correlates with increased pERK1/2 levels in patient specimens and disease progression. Treatment of cancer cells with PI3K inhibitors or taxane causes FOXO1 localization in the nucleus, increased expression of pERK1/2, and drug resistance. These effects are reversed by administering a small FOXO1-derived phospho-mimicking peptide inhibitor in vitro and in mice. Our results show a tumor suppressor role of AKT-phosphorylated FOXO1 in the cytoplasm and suggest that this function of FOXO1 can be harnessed to overcome chemoresistance in cancer.

JNK2 downregulation promotes tumorigenesis and chemoresistance by decreasing p53 stability in bladder cancer.

Bladder cancer is one of the most common malignancies of the urinary system, and the 5-year survival rate remains low. A comprehensive understanding of the carcinogenesis and progression of bladder cancer is urgently needed to advance treatment. c-Jun N-terminal kinase-2 (JNK2) exhibits both tumor promoter and tumor suppressor actions, depending on tumor type. Here, we analyzed the JNK2 function in bladder cancer. Using gene expression microarrays, we demonstrated that JNK2 mRNA is downregulated in an orthotopic rat model of bladder cancer. JNK2 protein levels were lower in rat and human bladder cancer tissues than in normal tissues, and the levels correlated with those of p53. Moreover, JNK2 phosphorylated p53 at Thr-81, thus protecting p53 from MDM2-induced proteasome degradation. Decreased expression of JNK2 in T24 cells conferred resistance to cell death induced by mitomycin C. Furthermore, lower JNK2 expression was associated with poorer overall survival among patients who underwent radical cystectomy. These results indicate that JNK2 acts as a tumor suppressor in bladder cancer, and that decreased JNK2 expression promotes bladder cancer tumorigenesis.

Engagement of integrinß1 induces resistance of bladder cancer cells to mitomycin-C.

OBJECTIVE: To identify whether integrinß1 subunit is responsible for the resistance of bladder cancer cell to the therapeutic drug mitomycin-C (MMC), when grown on fibronectin (FN). MATERIALS AND METHODS: The expression of integrinß1 on bladder cancer T24 and 5637 cells was examined by the flow cytometer. The adhesion of cells to plates with the absence or presence of FN was determined. Analysis of apoptosis induced by MMC was assessed using the flow cytometer in combination with an integrinß1-blocking antibody or siRNA targeting the coding region of integrinß1. Western blot was used to study the expression change of integrinß1 and its downstream molecules. RESULTS: Bladder cancer T24 and 5637 cells express high level of integrinß1 (87.3% ± 2.3 and 90.1% ± 1.9, respectively). Cellular adhesion to FN was significantly reduced by the blocking of integrinß1. Blocking or silencing of integrinß1 significantly abolished the drug resistance of cells grown on FN to MMC (P <.05) and inhibited the activation of survival signals phosphoinositide-3 kinase (PI3-K)/Akt. CONCLUSION: Integrinß1-mediated cellular adhesion to FN confers drug resistance to MMC on bladder cancer cells. Knockdown of integrinß1 may abolish the drug resistance phenotype and sensitize bladder cancer cells to MMC.

Cell adhesion to fibronectin induces mitomycin C resistance in bladder cancer cells.

OBJECTIVE: To investigate whether cell adhesion to fibronectin induces drug resistance in human bladder cancer cells, and to study the survival signalling pathway in cell adhesion to fibronectin-mediated chemotherapy resistance in vitro. MATERIALS AND METHODS: T24 cells (human bladder cancer cell lines) were pre-coated with fibronectin, and treated with mitomycin C (MMC) and the specific phosphoinositide-3 kinase (PI3-K) inhibitor LY294002. The apoptosis and cell cycles were analysed. The activity of the caspase-8, -9 and apoptosis-inducing factor (AIF) apoptosis pathways were assessed using colorimetric assay, immunofluorescence, Western blot and flow cytometry. The expression of glycogen synthase kinase-3beta (GSK-3beta) and cyclin D1, as the key regulator of G1/S phase transition, were determined by Western blot. The expression of PI3-K, Akt, phospho-Akt and beta1-integrin were also examined by Western blot. RESULTS: Apoptosis induced by MMC was significantly resisted by fibronectin adhesion in T24 cells, and this effect was through inhibition of the caspase-9 and AIF apoptosis pathways, but not the caspase-8 pathway. Fibronectin antagonized MMC-induced G0/G1-phase arrest by inactivating GSK-3beta to stabilize cyclin D1 expression in T24 cells. Furthermore, fibronectin-mediated protection of T24 cells was dependent on the activity of the PI3-K/Akt signalling pathway, and the protection could be abolished by the PI3-K inhibitor LY294002. CONCLUSIONS: Fibronectin-mediated PI3-K/Akt activation protects T24 cells from MMC-induced cell death through inhibition of both caspase-9 and AIF-mediated apoptosis and GSK-3beta/cyclin D1 involved G0/G1-phase arrest.

The effect of intravesical instillation of antifibrinolytic agents on bacillus Calmette-Guerin treatment of superficial bladder cancer: a pilot study.

PURPOSE: We determined whether intravesical instillation of antifibrinolytic agents could improve the antitumor effect of bacillus Calmette-Guerin. We also investigated the impact of these antifibrinolytic agents on the dose of bacillus Calmette-Guerin required for a therapeutic effect. MATERIALS AND METHODS: In this randomized, prospective, double-blind, controlled pilot study 257 patients with superficial bladder cancer were randomized into groups A through E. They received 100 to 120 mg intravesical bacillus Calmette-Guerin plus 100 mg para-aminomethylbenzoic acid, 50 to 60 mg bacillus Calmette-Guerin plus 100 mg para-aminomethylbenzoic acid, 100 to 120 mg bacillus Calmette-Guerin plus 2.0 gm epsilon aminocaproic acid, 50 to 60 mg bacillus Calmette-Guerin plus 2.0 gm epsilon aminocaproic acid and 100 to 120 mg bacillus Calmette-Guerin alone, respectively. Prothrombin time and activated partial thromboplastin time of each patient were determined at 2 hours after instillation, and adverse events were evaluated. Tumor recurrence was assessed every 3 months postoperatively by cystoscopy. Median followup was 26.0, 25.0, 24.5, 25.0 and 25.5 months, respectively. RESULTS: No significant change in prothrombin time or activated partial thromboplastin time was observed, and analysis showed no significant difference in prothrombin time or activated partial thromboplastin time among groups A through E (p = 0.693, 0.756). Recurrence rates at a minimum of median 2 years were 10.6%, 11.1%, 10.0%, 9.3% and 31.8% in groups A through E, respectively. The log rank test showed that recurrence-free probability was statistically different comparing groups A, B, C and D with group E, respectively (p = 0.023, 0.037, 0.031 and 0.020), while pairwise comparisons among groups A, B, C and D showed no significant differences (each p >0.05). The rate of serious adverse events in groups A through E was 9.6%, 3.9%, 15.7%, 5.9% and 13.5%, respectively. However, the differences were not significant (p = 0.222). CONCLUSIONS: Intravesical instillation of para-aminomethylbenzoic acid or epsilon aminocaproic acid is a more effective and safer method to improve the bacillus Calmette-Guerin antitumor effect, and can reduce the dose of bacillus Calmette-Guerin with the same effect as the full dose.

Study on enhancement of fibronectin-mediated bacillus Calmette-Guérin attachment to urinary bladder wall in rabbits.

To clarify whether intravesical usage of fibrin clot stabilizer epsilon-aminocaproic acid (EACA) or p-aminomethyl benzoic acid (PAMBA) and different injuries enhance fibronectin (FN)-mediated bacillus Calmette-Guérin (BCG) attachment to bladder wall. Thirty New Zealand male white rabbits were randomly divided into five groups and the bladder wall of each rabbit was injured by electrocautery, cryocautery or knife cutting on left lateral wall, right lateral wall and posterior wall in different groups, respectively. Different drug was instilled into the bladder: Group A: pure PBS; B: PBS and radiolabeled BCG ((3)H-BCG); C: EACA and (3)H-BCG; D: PAMBA and (3)H-BCG; E: heparin and (3)H-BCG. After instillation, each injured and non-injured bladder wall were surgically harvested and digested. The quantity of BCG attachment was detected by liquid scintillation counter (scintillation times per min, STPM). Quantity of BCG attachment to injured bladder wall was significantly (P < 0.01) greater than that of non-injured one, no matter which injury was performed. The BCG attachment to bladder wall in Group C or Group D was significantly (P < 0.05) greater than that of Group B. The quantity of BCG attachment to bladder of Group E was significantly (P < 0.05) less than that of Group B, C and D, respectively. Intravesical instillation of fibrin clot stabilizer (PAMBA, EACA) enhances FN-mediated BCG attachment to bladder wall while heparin inhibits this process. Injuries; e.g., cutting, cryocautery or electrocautery of bladder wall can significantly increase BCG attachment to the bladder wall.

[Surgical treatment of 486 cases of adrenal gland diseases: a retrospective study].

OBJECTIVE: To evaluate the roles of laparoscopic adrenalectomy (LA) and open adrenalectomy (GA) for treatment of adrenal gland diseases. METHODS: The data of 486 patients with adrenal gland diseases was analyzed retrospectively during 5 years. A total of 478 patients received surgical treatments including 318 GAs and 160 LAs. The operation time, bleeding volume during operation, intestine function recovery time, pain postoperatively, hospital stay time postoperatively and postoperative complications in group GA and group LA respectively were compared. RESULTS: All cases in group GA were successful. A total of 154 cases in group LA were successful, and 6 cases were converted to open surgery. In group LA, there were 9 cases whose tumor diameter exceeded 6 cm. There were 3 malignant cases in group LA, and no recurrence and metastasis were observed during 3-20 months follow-up. The average operation time was (112 +/- 16) mmn and (69 +/- 10) min in group GA and LA respectively. The average bleeding volume during operation was (286 +/- 23) ml, (56 +/- 10) ml in group GA and LA respectively. The average intestine function recovery time was (66 +/- 7) h, (24 +/- 7) h in group GA and LA respectively. The average frequency of treatment of pain was 1.9 +/- 0.4 and 0.5 +/- 0.1 in group GA and LA respectively. The average hospital stay time postoperatively was (10.3 +/- 1.1) d and (7.2 +/- 0.7) d in group GA and LA respectively. The rate of postoperative complications was 40.3% and 7.5% in group GA and LA respectively. All differences were significant (P = 0.023, 0.007, 0.039, 0.003, 0.029 and 0.001). CONCLUSIONS: LA has the added benefit of shorter convalescent times, improving patients satisfaction and less associated complications, as it has proved to be as effective as OA.