Upregulation of ROCK2 in gastric cancer cell promotes tumor cell proliferation, metastasis and invasion

Loss of DRD5P2 in hypoxia attenuates Rock2 degradation to promote EMT and gastric cancer metastasis

BACKGROUND

Metastasis is the leading cause of gastric cancer (GC)-related death. However, the molecular mechanisms underlying GC metastasis are not well understood. In this study, we focused on dopamine receptor 5 pseudogene 2 (DRD5P2), a novel long non-coding RNA, in GC metastasis.

METHODS

Expression of DRD5P2 in GC was detected by real-time PCR (RT-PCR) and fluorescence in situ hybridization (FISH). The effect of DRD5P2 in GC cells was examined by transwell invasion and migration assays. The pathways underlying DRD5P2/Rock2 signaling were studied by Western blot, co-immunoprecipitation (Co-IP), chromatin immunoprecipitation (ChIP) and RNA immunoprecipitation (RIP) analysis. Regulatory mechanism between hypoxia and DRD5P2 expression was explored in vitro by ChIP and Dual-luciferase reporter assays.

RESULTS

DRD5P2 expression is downregulated in advanced human GC and is associated with poor clinical outcomes. Gain- and loss-of-function studies showed that DRD5P2 inhibits GC cell migration, invasion, and epithelial-mesenchymal transition (EMT) in vitro, as well as peritoneal dissemination in vivo. Mechanistic analysis revealed that DRD5P2 binds with Rock2 and recruits the E3 ubiquitin ligase KAP1 to mediate Rock2 degradation, thus suppressing the Ezrin/HRAS/ERK/CREB pathway and ultimately attenuating Snail-mediated EMT and GC metastasis. Furthermore, DRD5P2 transcription is inhibited by hypoxia in a HIF-1α/ZNF263-dependent manner in GC cells.

CONCLUSIONS

DRD5P2 acts as a tumor suppressor in GC metastasis by suppressing Rock2/ERK/Snail signaling, and DRD5P2 is transcriptionally suppressed under hypoxia via the HIF-1α/ZNF263 axis.

The value of a nomogram based on 18F-FDG PET/CT metabolic parameters and metabolic heterogeneity in predicting distant metastasis in gastric cancer

OBJECTIVE

To investigate the value of metabolic parameters and metabolic heterogeneity from pretreatment deoxy-2-[fluorine-18]-fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) in predicting distant metastasis in gastric cancer.

METHODS

Eighty-six patients with pathologically confirmed gastric adenocarcinoma were included in this study. All patients underwent a whole-body 18F-FDG PET/CT scan before treatment. Clinicopathologic and imaging data were collected, including metabolic parameters such as maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary gastric cancer lesions. Heterogeneity index (HI)-1 was expressed as the absolute value of the linear regression slopes between the MTVs at different SUVmax thresholds (40% × SUVmax, 80% × SUVmax), while HI-2 was expressed as the difference between SUVmax and SUVmean. Patients were randomly divided into training and validation cohorts at a 7:3 ratio. The correlation between the above parameters and distant metastasis in gastric cancer was analyzed using the training cohort. A nomogram prediction model was then established and later verified with the validation cohort. Finally, decision curve analysis was used to evaluate the clinical utility of the model.

RESULTS

This study included 86 patients with gastric cancer, with 60 (69.8%) in the training cohort and 26 (30.2%) in the validation cohort. There was no significant difference in the balanced comparison between both cohorts (all P > .05). Among all patients, 31 (36.0%) developed distant metastasis, while 55 (64.0%) did not. In patients who developed distant tumor metastasis, carcinoembryonic antigen, carbohydrate antigen (CA)12-5, CA19-9, CA72-4, MTV, TLG, and HI-1 were significantly higher than in patients without distant metastasis (all P < .05). Multivariate logistic regression analysis identified CA72-4 (OR: 1.151, 95% CI: 1.020-1.300, P = .023) and HI-1 (OR: 1.647, 95% CI: 1.063-2.553, P = .026) as independent risk factors for predicting distant metastasis in gastric cancer. The nomogram constructed from this analysis exhibited high predictive efficacy in the training (AUC: 0.874, 95% CI: 0.766-0.983) and validation (AUC: 0.915, 95% CI: 0.790-1.000) cohorts, providing a net clinical benefit for patients.

CONCLUSION

HI-1 is an independent risk factor for predicting distant metastasis in gastric cancer. A comprehensive prediction model combining HI-1 with the tumor marker CA72-4 can increase the net clinical benefit for patients.

ROCK2 increases drug resistance in acute myeloid leukemia via metabolic reprogramming and MAPK/PI3K/AKT signaling

Rho-associated coiled-coil kinase 2 (ROCK2) is classified as a member of the serine/threonine protein kinase family and has been identified as a key driver of the development of various forms of cancer. The cause of ROCK2's impact on acute myeloid leukemia (AML) is still unknown. We found that ROCK2 expression was higher in AML patients, leading to lower complete response rates and worse overall survival. Additionally, ROCK2 expression was elevated in the doxorubicin-resistant leukemia cell line HL-60/ADM when compared to their individual parent cells. Moreover, the suppression or inhibition of ROCK2 leads to enhanced drug sensitivity in both AML cell lines and primary AML specimens, along with a notable decrease in downstream signaling pathways. Furthermore, the suppression of ROCK2 caused disruption of cellular energy production pathways by directly affecting the functionality of proteins within the mitochondrial electron transport chain. Finally, we discovered that TRIM26, a specific E3 ligase, is capable of ubiquitylating ROCK2, and the upregulation of TRIM26 within HL-60/ADM cells resulted in heightened sensitivity to the drug and reduced resistance. Thus, our study presents a new strategy for overcoming drug resistance in AML through targeting ROCK2/AKT/MAPK signaling pathway.

The Prognostic Importance of Ki-67 in Gastrointestinal Carcinomas: A Meta-analysis and Multi-omics Approach

PURPOSE

This study aimed to determine if Ki-67, a commonly used marker to measure tumor proliferation, is a reliable prognostic factor in various types of gastrointestinal (GI) cancers based on current high-quality multivariable evidence.

METHODS

A comprehensive search was conducted in PubMed, Embase, Scopus, and ISI Web of Science databases to investigate the association between Ki-67 positivity and overall survival (OS) and disease/recurrence-free survival (DFS/RFS) in GI cancers. Heterogeneity was assessed using Chi-square-based Q and I2 analyses and publication bias using funnel plots and Egger's analysis. In addition, Ki-67 levels in different GI cancers were examined by different platforms. The prognostic capability of Ki-67, gene ontology (GO), and pathway enrichment analysis were obtained from GEPIA2 and STRING.

RESULTS

Totally, 61 studies, involving 13,034 patients, were deemed eligible for our evaluation. The combined hazard ratios (HRs) demonstrated the prediction ability of overexpressed Ki-67 for a worse OS (HR: 1.67, P < 0.001; HR: 1.37, P = 0.021) and DFS/RFS (HR: 2.06, P < 0.001) in hepatocellular and pancreatic malignancies, respectively, as confirmed by multi-omics databases. However, similar correlation was not found in esophageal, gastric, and colorectal cancers. Furthermore, most of the associations were identified to be robust based on different subcategories and publication bias assessment. Finally, enriched Ki-67-related genes were found to be involved in various important signaling pathways, such as cell cycle, P53 signaling network, and DNA damage responses.

CONCLUSION

This study supports that Ki-67 can serve as an independent prognostic biomarker for pancreatic and hepatocellular malignancies in clinical settings.

Predictive value of 18F-FDG PET/CT multi-metabolic parameters and tumor metabolic heterogeneity in the prognosis of gastric cancer

OBJECTIVE

We aimed to investigate the predictive value of pre-treatment 18F-FDG PET/CT multi-metabolic parameters and tumor metabolic heterogeneity for gastric cancer prognosis.

METHODS

Seventy-one patients with gastric cancer were included. All patients underwent 18F-FDG PET/CT whole-body scans prior to treatment and had pathologically confirmed gastric adenocarcinomas. Each metabolic parameter, including SUVmax, SUVmean, MTV, and TLG, was collected from the primary lesions of gastric cancer in all patients, and the slope of the linear regression between the MTV corresponding to different SUVmax thresholds (40% × SUVmax, 80% × SUVmax) of the primary lesions was calculated. The absolute value of the slope was regarded as the metabolic heterogeneity of the primary lesions, expressed as the heterogeneity index HI-1, and the coefficient of variance of the SUVmean of the primary lesions was regarded as HI-2. Patient prognosis was assessed by PFS and OS, and a nomogram of the prognostic prediction model was constructed, after which the clinical utility of the model was assessed using DCA.

RESULTS

A total of 71 patients with gastric cancer, including 57 (80.3%) males and 14 (19.7%) females, had a mean age of 61 ± 10 years; disease progression occurred in 27 (38.0%) patients and death occurred in 24 (33.8%) patients. Multivariate Cox regression analysis showed that HI-1 alone was a common independent risk factor for PFS (HR: 1.183; 95% CI: 1.010-1.387, P < 0.05) and OS (HR: 1.214; 95% CI: 1.016-1.450, P < 0.05) in patients with gastric cancer. A nomogram created based on the results of Cox regression analysis increased the net clinical benefit for patients. Considering disease progression as a positive event, patients were divided into low-, intermediate-, and high-risk groups, and Kaplan-Meier survival analysis showed that there were significant differences in PFS among the three groups. When death was considered a positive event and patients were included in the low- and high-risk groups, there were significant differences in OS between the two groups.

CONCLUSION

The heterogeneity index HI-1 of primary gastric cancer lesions is an independent risk factor for patient prognosis. A nomogram of prognostic prediction models constructed for each independent factor can increase the net clinical benefit and stratify the risk level of patients, providing a reference for guiding individualized patient treatment.

ITGB1-mediated molecular landscape and cuproptosis phenotype induced the worse prognosis in diffuse gastric cancer

Diffuse type gastric cancer was identified with relatively worse prognosis than other Lauren’s histological classification. Integrin β1 (ITGB1) was a member of integrin family which played a markedly important role in tumorigenesis and progression. However, the influence of ITGB1 in diffuse gastric cancer (DGC) remains uncertain. Here, we leveraged the transcriptomic and proteomic data to explore the association between ITGB1 expression and clinicopathologic information and biological process in DGC. Cell phenotype experiments combined with quantitative-PCR (q-PCR) and western blotting were utilized to identify the potential molecular mechanism underling ITGB1.Transcriptomics and proteomics both revealed that the higher ITGB1 expression was significantly associated with worse prognosis in DGC, but not in intestinal GC. Genomic analysis indicated that the mutation frequency of significantly mutated genes of ARID1A and COL11A1, and mutational signatures of SBS6 and SBS15 were markedly increased in the ITGB1 low expression subgroup. The enrichment analysis revealed diverse pathways related to dysregulation of ITGB1 in DGC, especially in cell adhesion, proliferation, metabolism reprogramming, and immune regulation alterations. Elevated activities of kinase-ROCK1, PKACA/PRKACA and AKT1 were observed in the ITGB1 high-expression subgroup. The ssGSEA analysis also found that ITGB1 low-expression had a higher cuproptosis score and was negatively correlated with key regulators of cuproptosis, including FDX1, DLAT, and DLST. We further observed that the upregulated expression of mitochondrial tricarboxylic acid (TCA) cycle in the ITGB1 low-expression group. Reduced expression of ITGB1 inhibited the ability of cell proliferation and motility and also potentiated the cell sensitive to copper ionophores via western blotting assay. Overall, this study revealed that ITGB1 was a protumorigenic gene and regulated tumor metabolism and cuproptosis in DGC.

Discovery of unglycosylated indolocarbazoles as ROCK2 isoform-selective inhibitors for the treatment of breast cancer metastasis

Breast cancer metastasis is a major challenge in clinical therapy because of the absence of effective treatments. Rho-associated coiled-coil kinase (ROCK), which is essential for cell invasion and migration, has recently been suggested as a potential target for the treatment of cancer metastasis. Herein, we report the structure-activity relationships (SAR) of indolocarbazoles against ROCK2 and reveal the crucial role of the C-3 hydroxyl for ROCK2 inhibition. The most potent unglycosylated aglycone THK01 was demonstrated to bind to and stabilize ROCK2 with potent anti-metastatic effects in breast cancer in vitro and in vivo with no obvious toxicities. Further mechanistic studies revealed that the anti-metastatic effect of THK01 was closely related to the suppression of STAT3^Y705 activation. Moreover, THK01 exhibited excellent selectivity over the isoform protein ROCK1 (>100-fold). Taken together, with low toxicity, the ROCK2 inhibitor THK01 potently inhibited breast cancer metastasis through the ROCK2-STAT3 signaling pathway, which offers a new opportunity for the treatment of metastatic breast cancer.

5-Azacytidine Downregulates the Proliferation and Migration of Hepatocellular Carcinoma Cells In Vitro and In Vivo by Targeting miR-139-5p/ROCK2 Pathway

BACKGROUND

For hepatocellular carcinoma (HCC), effective therapeutic approaches are lacking. As aberrant gene methylation is a major contributor to HCC development, demethylating drugs such as 5-azacytidine (5-Aza) have been proposed. As most 5-Aza mechanisms of action are unknown, we investigated its phenotypic/molecular effects.

METHODS

5-Aza effects were examined in the human HCC cell lines JHH-6/HuH-7 and in the rat cell-line N1-S1. We also employed a xenograft mouse model (HuH-7), a zebrafish model (JHH-6), and an orthotopic syngeneic rat model (N1-S1) of HCC.

RESULTS

5-Aza downregulated cell viability/growth/migration/adhesion by upregulating miR-139-5p, which in turn downregulated ROCK2/cyclin D1/E2F1 and increased p27kip1, resulting in G1/G0 cell accumulation. Moreover, a decrease in cyclin B1 and an increase in p27kip1 led to G2/M accumulation. Finally, we observed a decrease in MMP-2 levels, a stimulator of HCC cell migration. Aza effects were confirmed in the mouse model; in the zebrafish model, we also demonstrated the downregulation of tumor neo-angiogenesis, and in the orthotopic rat model, we observed impaired N1-S1 grafting in a healthy liver.

CONCLUSION

We demonstrate for the first time that 5-Aza can impair HCC development via upregulation of miR-139-5p, which in turn impairs the ROCK2/cyclin D1/E2F1/cyclin B1 pro-proliferative pathway and the ROCK2/MMP-2 pro-migratory pathway. Thus, we provide novel information about 5-Aza mechanisms of action and deepen the knowledge about the crosstalk among ROCK2/cyclin D1/E2F1/cyclin B1/p27kip1/MMP-2 in HCC.

Down-Regulating HAUS6 Suppresses Cell Proliferation by Activating the p53/p21 Pathway in Colorectal Cancer

Background: HAUS6 participates in microtubule-dependent microtubule amplification, but its role in malignancies including colorectal cancer (CRC) has not been explored. We therefore assessed the potential oncogenic activities of HAUS6 in CRC. Results: HAUS6 mRNA and protein expression is higher in CRC tissues, and high HAUS6 expression is correlated with shorter overall survival in CRC patients. HAUS6 knockdown in CRC cell lines suppressed cell growth in vitro and in vivo by inhibiting cell viability, survival and arresting cell cycle progression at G0/G1, while HAUS6 over-expression increased cell viability. We showed that these effects are dependent on activation of the p53/p21 signalling pathway by reducing p53 and p21 degradation. Moreover, combination of HAUS6 knockdown and 5-FU treatment further enhanced the suppression of cell proliferation of CRC cells by increasing activation of the p53/p21 pathway. Conclusion: Our study highlights a potential oncogenic role for HAUS6 in CRC. Targeting HAUS6 may be a promising novel prognostic marker and chemotherapeutic target for treating CRC patients.

Prognostic Value of Intratumor Metabolic Heterogeneity Parameters on 18F-FDG PET/CT for Patients with Colorectal Cancer

Purpose

Intratumor metabolic heterogeneity parameters on ¹⁸F-2-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography-computed tomography (PET-CT) have been proven to be predictors of the clinical prognosis of cancer patients. The study aimed to examine the correlation between ¹⁸F-FDG PET-CT-defined heterogeneity parameters and the prognostic significance in patients with colorectal cancer.

Methods

The study included 188 patients with colorectal cancer who received surgery and ¹⁸F-FDG PET/CT examinations. Preoperative ¹⁸F-FDG PET/CT conventional and metabolic heterogeneity parameters were collected, including maximum, peak, and mean standardized uptake value (SUVmax, SUVpeak, and SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG), heterogeneity index-1 (HI-1) and heterogeneity index-2 (HI-2), and clinicopathological information. Correlations between these parameters and patient survival outcomes were inferred.

Results

The associations between ¹⁸F-FDG PET/CT parameters and clinical outcomes were analyzed. Tumor thrombus (P < 0.001), tumor stage (P=0.001), MTV (P=0.003), HI-1 (P=0.032), and HI-2 (P=0.001) differed between the two groups with and without recurrence. Multivariate analysis showed that, in the radical surgery group, HI-2 (HR = 1.10, 95% CI: 1.04–1.17, P=0.001), tumor stage (HR = 20.65, 95% CI: 4.81–88.62, P < 0.001), and regional lymph nodes status (HR = 0.16, 95% CI: 0.04–0.57, P=0.005) were independent variables significantly correlated with progression-free survival (PFS) and HI-2 (HR = 1.16, 95% CI: 1.07–1.26, P < 0.001) was an independent variable affecting overall survival (OS). In the palliative surgery group, HI-2 (HR = 1.03, 95% CI: 1.01–1.06, P=0.020) was an independent variable affecting PFS, and all the parameters were not statistically significant for OS.

Conclusion

HI-2, tumor stage, and regional lymph nodes status might predict the outcomes of colorectal cancer more effectively than other ¹⁸F-FDG PET/CT defined parameters.

Precise Identification of Recurrent Somatic Mutations in Oral Cancer Through Whole-Exome Sequencing Using Multiple Mutation Calling Pipelines

Understanding the genomic alterations in oral carcinogenesis remains crucial for the appropriate diagnosis and treatment of oral squamous cell carcinoma (OSCC). To unveil the mutational spectrum, in this study, we conducted whole-exome sequencing (WES), using six mutation calling pipelines and multiple filtering criteria applied to 50 paired OSCC samples. The tumor mutation burden extracted from the data set of somatic variations was significantly associated with age, tumor staging, and survival. Several genes (MUC16, MUC19, KMT2D, TTN, HERC2) with a high frequency of false positive mutations were identified. Moreover, known (TP53, FAT1, EPHA2, NOTCH1, CASP8, and PIK3CA) and novel (HYDIN, ALPK3, ASXL1, USP9X, SKOR2, CPLANE1, STARD9, and NSD2) genes have been found to be significantly and frequently mutated in OSCC. Further analysis of gene alteration status with clinical parameters revealed that canonical pathways, including clathrin-mediated endocytotic signaling, NFκB signaling, PEDF signaling, and calcium signaling were associated with OSCC prognosis. Defining a catalog of targetable genomic alterations showed that 58% of the tumors carried at least one aberrant event that may potentially be targeted by approved therapeutic agents. We found molecular OSCC subgroups which were correlated with etiology and prognosis while defining the landscape of major altered events in the coding regions of OSCC genomes. These findings provide information that will be helpful in the design of clinical trials on targeted therapies and in the stratification of patients with OSCC according to therapeutic efficacy.

circNSUN2 promotes the malignant biological behavior of colorectal cancer cells via the miR‑181a‑5p/ROCK2 axis

Aberrant expression of circular RNAs (circRNAs) has been demonstrated to be related to the development of colorectal cancer (CRC), the third most common cancer worldwide. However, the mechanism of the effect of circRNA NOP2/Sun domain family, member 2 (circNSUN2) on the malignant biological behavior of CRC remains unclear. In the present study, the expression of circNSUN2 and microRNA (miR)‑181a‑5p was detected by RT‑qPCR. The expression of Rho‑associated coiled‑coil‑containing protein kinase 2 (ROCK2) was measured by western blotting. Cell proliferation was detected by CCK‑8 assay. The cell apoptosis rate was measured by flow cytometry. Cell migration ability was evaluated by Transwell assay. The interactions between circNSUN2, miR‑181a‑5p and ROCK2 were verified by dual‑luciferase reporter assay. The results revealed that circNSUN2 was highly expressed in CRC tissues and cell lines. Knockdown of circNSUN2 inhibited the malignant biological behavior of CRC in vivo and in vitro. Moreover, miR‑181a‑5p was revealed to be a target gene of circNSUN2, and the expression of ROCK2 was negatively regulated by miR‑181a‑5p. Knockdown of circNSUN2 inhibited proliferation and migration, and induced apoptosis of CRC cells and suppressed tumor growth by targeting miR‑181a‑5p to decrease ROCK2 expression. In conclusion, circNSUN2 promoted the progression of CRC by sponging miR‑181a‑5p to increase the expression of ROCK2.

Genomic and Epigenomic Profile of Uterine Smooth Muscle Tumors of Uncertain Malignant Potential (STUMPs) Revealed Similarities and Differences with Leiomyomas and Leiomyosarcomas

Uterine smooth muscle tumors of uncertain malignant potential (STUMPs) represent a heterogeneous group of tumors that cannot be histologically diagnosed as unequivocally benign or malignant. For this reason, many authors are working to obtain a better definition of diagnostic and prognostic criteria. In this work, we analyzed the genomic and epigenomic profile of uterine smooth muscle tumors (USMTs) in order to find similarities and differences between STUMPs, leiomyosarcomas (LMSs) and leiomyomas (LMs), and possibly identify prognostic factors in this group of tumors. Array-CGH data on 23 USMTs demonstrated the presence of a more similar genomic profile between STUMPs and LMSs. Some genes, such as PRKDC and PUM2, with a potential prognostic value, were never previously associated with STUMP. The methylation data appears to be very promising, especially with regards to the divergent profile found in the sample that relapsed, characterized by an overall CGI hypomethylation. Finally, the Gene Ontology analysis highlighted some cancer genes that could play a pivotal role in the unexpected aggressive behavior that can be found in some of these tumors. These genes could prove to be prognostic markers in the future.

circCUL2 regulates gastric cancer malignant transformation and cisplatin resistance by modulating autophagy activation via miR-142-3p/ROCK2

Background

Circular RNAs (circRNAs) are a class of noncoding RNAs (ncRNAs) and can modulate gene expression by binding to miRNAs; further, circRNAs have been shown to participate in several pathological processes. However, the expression and biological function of circCUL2 in gastric cancer (GC) remains largely unknown.

Methods

circRNA microarrays and quantitative real-time PCR (qRT-PCR) were used to identify differentially expressed circRNAs in GC tissues and cell lines. circCUL2 knockdown and overexpression were performed to indicate the functional role of circCUL2 in vitro and in vivo. The expression and regulation of circCUL2, miR-142-3p and ROCK2 were evaluated using fluorescence in situ hybridization (FISH), dual-luciferase assays, RNA pull-down assays, RNA immunoprecipitation (RIP) and rescue experiments. Furthermore, the regulation of cisplatin sensitivity and autophagy by circCUL2/miR-142-3p/ROCK2 was demonstrated by cellular apoptosis assays, western blot, immunofluorescence and transmission electron microscopy analyses.

Results

The level of circCUL2, which is stable and cytoplasmically localized, was significantly reduced in GC tissues and cells. Overexpressed circCUL2 inhibited malignant transformation in vitro and tumorigenicity in vivo. In the AGS and SGC-7901 cell lines, circCUL2 sponged miR-142-3p to regulate ROCK2, thus modulating tumor progression. Furthermore, in the AGS/DDP and SGC-7901/DDP cell lines, circCUL2 regulated cisplatin sensitivity through miR-142-3p/ROCK2-mediated autophagy activation.

Conclusion

circCUL2 may function as a tumor suppressor and regulator of cisplatin sensitivity through miR-142-3p/ROCK2-mediated autophagy activation, which could be a key mechanism and therapeutic target for GC.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12943-020-01270-x.

Circular RNA circ_HN1 facilitates gastric cancer progression through modulation of the miR-302b-3p/ROCK2 axis

Gastric cancer (GC) is a malignant tumor with high morbidity and mortality in the world. Circular RNA hsa_circHN1_005 (circ_HN1), also termed as hsa_circ_0045602, is reported as an oncogene in GC. However, the molecular mechanism of circ_HN1 in GC development has not been fully explored. Here, we surveyed the regulatory mechanism of circ_HN1 in GC progression. The levels of circ_HN1, miR-302b-3p, and rho-associated coiled-coil containing protein kinase 2 (ROCK2) mRNA were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, apoptosis, colony formation, cell cycle progresion, migration, and invasion were determined by using cell counting, flow cytometry, colony formation, or transwell assays. Protein levels were detected with Western blotting. The relationship between circ_HN1 or ROCK2 and miR-302b-3p was verified via dual luciferase reporter or RNA immunoprecipitation (RIP) assays. The role of circ_HN1 in vivo was confirmed by xenograft assay. We observed that circ_HN1 and ROCK2 were upregulated while miR-302b-3p was downregulated in GC tissues and cells. Circ_HN1 silencing slowed tumor growth in vivo and impeded cell proliferation migration, invasion, and facilitated cell apoptosis in GC cells in vitro. Circ_HN1 sponged miR-302b-3p to regulate ROCK2 expression. MiR-302b-3p inhibitor reversed circ_HN1 silencing-mediated influence on the malignant behaviors of GC cells. Furthermore, ROCK2 overexpression restored miR-302b-3p mimic-mediated impacts on cell malignant behaviors in GC cells. In conclusion, circ_HN1 exerted an oncogenic role in GC through upregulating ROCK2 via sponging miR-302b-3p, offering evidence that circ_HN1 is a potential target for GC therapy.

Intra-tumor metabolic heterogeneity of gastric cancer on 18F-FDG PETCT indicates patient survival outcomes

The present study aimed to investigate the prognostic value of intra-tumor metabolic heterogeneity on 2-[18F] Fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) for patients with gastric cancer. Fifty-five patients with advanced gastric cancer that had received neoadjuvant chemotherapy and radical surgery were included. Clinicopathological information, ¹⁸F-FDG PET/CT before chemotherapy, pathological response, recurrence or metastasis, progression-free survival (PFS), and overall survival (OS) of the patients were collected. The maximum, peak, and mean standardized uptake values (SUV_max, SUV_peak, and SUV_mean), tumor-to-liver ratio (TLR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on PET/CT were measured. Heterogeneity index-1 (HI-1) was calculated as SUV_mean divided by the standard deviation, and heterogeneity index-2 (HI-2) was evaluated through linear regressions of MTVs according to different SUV thresholds. Associations between these parameters and patient survival outcomes were analyzed. None of the parameters on PET were associated with tumor recurrence. Pathological responders had significantly smaller TLR, MTV and HI-2 values than non-responders (P = 0.017, 0.017 and 0.013, respectively). In multivariate analysis of PFS, only HI-2 was an independent factor (hazard ratio [HR] = 2.693, P = 0.005) after adjusting for clinical tumor-node-metastasis (TNM) stage. In multivariate analysis of OS, HI-2 was also an independent predictive factor (HR = 2.281, P = 0.009) after adjusting for tumor recurrence. Thus, HI-2 generated from baseline ¹⁸F-FDG PET/CT is significantly associated with survival of patients with gastric cancer. Preoperative assessment of HI-2 by ¹⁸F-FDG PET/CT might be promising to identify patients with poor prognosis.

Should we keep rocking? Portraits from targeting Rho kinases in cancer

Cancer targeted therapy, either alone or in combination with conventional chemotherapy, could allow the survival of patients with neoplasms currently considered incurable. In recent years, the dysregulation of the Rho-associated coiled-coil kinases (ROCK1 and ROCK2) has been associated with increased metastasis and poorer patient survival in several tumor types, and due to their essential roles in regulating the cytoskeleton, have gained popularity and progressively been researched as targets for the development of novel anti-cancer drugs. Nevertheless, in a pediatric scenario, the influence of both isoforms on prognosis remains a controversial issue. In this review, we summarize the functions of ROCKs, compile their roles in human cancer and their value as prognostic factors in both, adult and pediatric cancer. Moreover, we provide the up-to-date advances on their pharmacological inhibition in pre-clinical models and clinical trials. Alternatively, we highlight and discuss detrimental effects of ROCK inhibition provoked not only by the action on off-targets, but most importantly, by pro-survival effects on cancer stem cells, dormant cells, and circulating tumor cells, along with cell-context or microenvironment-dependent contradictory responses. Together these drawbacks represent a risk for cancer cell dissemination and metastasis after anti-ROCK intervention, a caveat that should concern scientists and clinicians.

mi-R4435-2HG promotes proliferation and inhibits apoptosis of cancer cells in ovarian carcinoma by upregulating ROCK2

The present study aimed to investigate the involvement of long noncoding RNA mi-R4435-2HG in ovarian carcinoma. mi-R4435-2HG and Rho-associated protein kinase 2 (ROCK2) were demonstrated to both be upregulated in ovarian carcinoma. mi-R4435-2HG and ROCK2 were positively correlated in both tumor and healthy tissues. mi-R4435-2HG overexpression mediated the upregulation of ROCK2, while upregulation of ROCK2 did not affect mi-R4435-2HG. Overexpression of mi-R4435-2HG and ROCK2 led to promoted proliferation and inhibited apoptosis of cancer cells, while mi-R4435-2HG and ROCK2 knockdown had the opposite effect. In addition, ROCK2 knockdown attenuated the effects of mi-R4435-2HG overexpression on cancer cell proliferation and apoptosis. Therefore, mi-R4435-2HG promotes proliferation and inhibits apoptosis of cancer cells in ovarian carcinoma by upregulating ROCK2.

Myosin Heavy Chain-Associated RNA Transcripts Promotes Gastric Cancer Progression Through the miR-4529-5p/ROCK2 Axis

BACKGROUND AND AIM

Characterization of genetic aberrations provides novel strategies for diagnosis and treatment of gastric cancer. Accumulating evidence has shown the involvement of long non-coding RNA (lncRNA) in the pathology of gastric cancer, especially in proliferation and metastasis. The aim of this study was to delineate the role of myosin heavy chain-associated RNA transcripts (MHRT), a heart-specific lncRNA, in gastric cancer and to understand the correlation between MHRT, miR-4529-5p, and ROCK2.

METHODS

To study expression level of MHRT, clinical gastric cancer samples, gastric cancer cell lines, adjacent normal tissues, and gastric epithelial cell lines were used. Additionally, apoptosis, proliferation, and invasion of gastric cancer cells were studied with or without downregulation of MHRT and miR-4529-5p.

RESULTS

We identified that MHRT was ectopically expressed in gastric cancer tissues and cell lines. Interestingly, similar to the anti-apoptotic role of MHRT in cardiomyocytes, our data illustrated that MHRT inhibits apoptosis of gastric cancer cells. Moreover, we found that MHRT promotes proliferation and invasion of gastric cancer cells in vitro. Importantly, our data revealed that MHRT regulates the expression of miR-4529-5p via direct binding. Additionally, functional experiments illustrated that miR-4529-5p is particularly responsible for MHRT-mediated regulation of apoptosis. Besides, ROCK2 was identified as a downstream target of miR-4529-5p. Additionally, upregulated MHRT promotes the expression of ROCK2 by inhibiting miR-4529-5p.

CONCLUSION

Our data illustrated a MHRT/miR-4529-5p/ROCK2 regulatory axis that contributes to the tumorigenesis of gastric cancer and provided potential therapeutic targets for precise gastric cancer treatment.

MicroRNA-466 inhibits cancer cell migration and invasion in hepatocellular carcinoma by indirectly mediating the downregulation of ROCK2

MicroRNA-466 was recently characterized as a tumor suppressor with known biological function in prostate cancer. The aim of the current study was to investigate the possible involvement of microRNA-466 in hepatocellular carcinoma (HCC). The current study demonstrated that the expression level of microRNA-466 was significantly downregulated; while the mRNA expression level of Rho-associated coiled-coil containing protein kinase 2 (ROCK2) was significantly upregulated in tumor tissue compared with adjacent healthy tissue samples obtained from patients with HCC. In addition, the relative plasma level of microRNA-466 was significantly decreased, while the relative plasma level of ROCK2 was significantly increased in patients with HCC compared with healthy controls. Expression levels of microRNA-466 and ROCK2 were inversely correlated in tumor tissue but not in adjacent healthy tissue samples obtained from patients with HCC. Plasma levels of microRNA-466 and ROCK2 were inversely correlated in patients with HCC but not in healthy controls. In addition, reduced plasma levels of microRNA-466 may have a diagnostic value in the detection of early stage HCC. MicroRNA-466 overexpression significantly suppressed ROCK2 expression in HCC cells, whereas ROCK2 overexpression did not significantly affect microRNA-466 expression. MicroRNA-466 overexpression significantly suppressed, while ROCK2 overexpression significantly enhanced HCC cell migration and invasion. In addition, ROCK2 overexpression partially reversed the inhibitory effect of microRNA-466 overexpression on HCC cell migration and invasion. Taken together, these results suggest that microRNA-466 may inhibit HCC cell migration and invasion by indirectly mediating the downregulation of ROCK2.

MicroRNA‑122 downregulates Rho‑associated protein kinase 2 expression and inhibits the proliferation of prostate carcinoma cells

MicroRNA‑122 (miR‑122) has been reported to be involved in the pathogenesis of several types of malignancies; however, its role in prostate carcinoma remains unknown. Thus, the current study aimed to investigate the functionality of miR‑122 in prostate carcinoma. Clinical data of 54 patients with prostate carcinoma who were diagnosed and treated in Union Hospital (Wuhan, China) between January 2011 and January 2013 were retrospectively analyzed. The expression levels of miR‑122 and Rho‑associated protein kinase 2 (ROCK2) in prostate tumor and adjacent healthy tissues of patients, as well as in the serum of prostate carcinoma patients and healthy controls, were detected by reverse transcription‑quantitative polymerase chain reaction. Receiver operating characteristic curve and survival curve analyses were used to examine the diagnostic and prognostic values of serum miR‑122 for prostate carcinoma. In addition, miR‑122 mimic was transfected into prostate carcinoma cells, and the effects on cell proliferation and ROCK2 expression were explored by Cell Counting Kit‑8 and western blot assays, respectively. It was observed that miR‑122 was downregulated and ROCK2 was upregulated in tumor tissues as compared with their levels in adjacent healthy tissues. miR‑122 level in the serum was also markedly lower in prostate carcinoma patients in comparison with that in healthy controls. Furthermore, a low serum level of miR‑122 was found to effectively distinguish the prostate carcinoma patients from healthy controls and to be an indicator of poor survival. In prostate carcinoma cells, miR‑122 overexpression inhibited the proliferation and the expression of ROCK2. Taken together, miR‑122 may inhibit the proliferation of prostate carcinoma cells possibly by downregulating ROCK2 expression.

Overexpression of Rho-Associated Coiled-Coil Containing Protein Kinase 2 Is Correlated with Clinical Progression and Poor Prognosis in Breast Cancer

Background

Rho-associated coiled-coil containing protein kinases 2 (ROCK2) is one of the best characterized targets for the small GTPase Rho. It has been reported that ROCK2 is critical for cancer cell migration and invasion. The objective of this study was to investigate the association of ROCK2 expression with clinicopathological features and overall survival of breast cancer patients.

Material/Methods

The expression of ROCK2 in breast cancer and paired adjacent normal tissues was detected and compared by immunohistochemical staining of tissue array. ROCK2 mRNA expression and clinicopathological information was extracted from the TCGA breast cancer dataset. The association of ROCK2 expression with the clinicopathological characteristics of patients with breast cancer was evaluated using univariate and multivariate Cox proportional hazards models. Overall survival was analyzed using the Kaplan-Meier method.

Results

Immunohistochemistry showed that ROCK2 expression was significantly higher in tumor tissues than in paired adjacent normal tissues [immunoreactivity score (IRS): tumor, 5.25±2.10, n=40 vs. adjacent normal 3.83±1.06, n=40, P<0.01]. The IRS was correlated to breast cancer staging. Similarly, the mRNA level of ROCK2 was correlated to tumor stage. Notably, ROCK2 mRNA expression (hazard ratio [HR] 1.665 and 95% confidence interval [CI] 1.115–2.488, P=0.013) were also associated with overall survival in a multivariate analysis.

Conclusions

Upregulation of ROCK2 was associated with the progression of breast cancer. High expression of ROCK2 may predict poor overall survival rates for breast cancer patients.

Substrate rigidity-dependent positive feedback regulation between YAP and ROCK2

Extracellular matrix (ECM) stiffness influences gene expression, leading to modulation of various cellular functions. While ROCK2 regulates actomyosin activity as well as cell migration and proliferation, expression of ROCK2 is increased in response to stiffening ECM. However, the mechanism underlying rigidity-dependent ROCK2 expression remains elusive. Here, we show that YAP, a mechanically regulated transcription coactivator, upregulates ROCK2 expression in an ECM rigidity-dependent manner. YAP interacted with the ROCK2 promoter region in an actomyosin activity-dependent manner. Knockdown of YAP decreased ROCK2 expression while activity of the ROCK2 promoter was upregulated by expressing constitutively active YAP. Furthermore, we found that ROCK2 expression promotes transcriptional activation by YAP. Our results reveal a novel positive feedback loop between YAP and ROCK2, which is modulated by ECM stiffness.

Clinicopathologic significance of ROCK2 expression in oral squamous cell carcinomas

BACKGROUND

Rho-associated coiled-coil kinase 2 (ROCK2) is an oncoprotein that controls cytoskeleton organization and acts as prognostic marker in different types of solid tumors. ROCK2 overexpression is also observed in cancer-associated fibroblasts (CAF), which suggests its relevance within the tumor microenvironment. This study aimed to access the prognostic value of ROCK2 in oral squamous cell carcinomas (OSCCs) and its association with CAF density.

METHODS

Rho-associated coiled-coil kinase 2 immunohistochemical analysis was applied in 93 OSCC samples from 2 centers in Brazil and Finland. The samples were also stained for isoform α of smooth muscle actin (α-SMA) to characterize the presence of CAF in the tumor stroma. Clinicopathological associations were analyzed using Chi-squared test, survival curves were constructed according to the Kaplan-Meier method, and Cox proportional hazard model was applied for multivariate survival analysis.

RESULTS

Advanced clinical stage (P = .002) and increased density of CAF (P = .002) were significantly associated with high ROCK2 expression. The high expression of ROCK2 was also associated with shortened disease-specific survival (HR: 2.22, 95% CI: 1.15-4.38, P = .04), but the association did not withstand the Cox multivariate survival analysis.

CONCLUSIONS

The findings suggest that high ROCK2 expression in OSCC is associated with advanced disease and follows the increase in CAF density, which may be important for tumor progression.