Expression of the hyaluronan-mediated motility receptor RHAMM in tumor budding cells identifies aggressive colorectal cancers

Extracellular matrix remodeling in tumor progression and immune escape: from mechanisms to treatments

The malignant tumor is a multi-etiological, systemic and complex disease characterized by uncontrolled cell proliferation and distant metastasis. Anticancer treatments including adjuvant therapies and targeted therapies are effective in eliminating cancer cells but in a limited number of patients. Increasing evidence suggests that the extracellular matrix (ECM) plays an important role in tumor development through changes in macromolecule components, degradation enzymes and stiffness. These variations are under the control of cellular components in tumor tissue via the aberrant activation of signaling pathways, the interaction of the ECM components to multiple surface receptors, and mechanical impact. Additionally, the ECM shaped by cancer regulates immune cells which results in an immune suppressive microenvironment and hinders the efficacy of immunotherapies. Thus, the ECM acts as a barrier to protect cancer from treatments and supports tumor progression. Nevertheless, the profound regulatory network of the ECM remodeling hampers the design of individualized antitumor treatment. Here, we elaborate on the composition of the malignant ECM, and discuss the specific mechanisms of the ECM remodeling. Precisely, we highlight the impact of the ECM remodeling on tumor development, including proliferation, anoikis, metastasis, angiogenesis, lymphangiogenesis, and immune escape. Finally, we emphasize ECM "normalization" as a potential strategy for anti-malignant treatment.

Deregulated hyaluronan metabolism in the tumor microenvironment drives cancer inflammation and tumor-associated immune suppression

Hyaluronan (HA) is known to be a prominent component of the extracellular matrix in tumors, and many solid cancers are characterized by aberrant HA metabolism resulting in increased production in tumor tissue. HA has been implicated in regulating a variety of cellular functions in tumor cells and tumor-associated stromal cells, suggesting that altered HA metabolism can influence tumor growth and malignancy at multiple levels. Importantly, increased HA production in cancer is associated with enhanced HA degradation due to high levels of expression and activity of hyaluronidases (Hyal). Understanding the complex molecular and cellular mechanisms involved in abnormal HA metabolism and catabolism in solid cancers could have important implications for the design of future cancer therapeutic approaches. It appears that extensive crosstalk between immune cells and HA-enriched stroma contributes to tumor growth and progression in several ways. Specifically, the interaction of tumor-recruited Hyal2-expressing myeloid-derived suppressor cells (MDSCs) of bone marrow origin with HA-producing cancer-associated fibroblasts and epithelial tumor cells results in enhanced HA degradation and accumulation of small pro-inflammatory HA fragments, which further drives cancer-related inflammation. In addition, hyaluronan-enriched stroma supports the transition of tumor-recruited Hyal2⁺MDSCs to the PD-L1⁺ tumor-associated macrophages leading to the formation of an immunosuppressive and tolerogenic tumor microenvironment. In this review, we aim to discuss the contribution of tumor-associated HA to cancer inflammation, angiogenesis, and tumor-associated immune suppression. We also highlight the recent findings related to the enhanced HA degradation in the tumor microenvironment.

The role of RHAMM in cancer: Exposing novel therapeutic vulnerabilities

Receptor for hyaluronic acid-mediated motility (RHAMM) is a cell surface receptor for hyaluronic acid that is critical for cell migration and a cell cycle protein involved in microtubule assembly and stability. These functions of RHAMM are required for cellular stress responses and cell cycle progression but are also exploited by tumor cells for malignant progression and metastasis. RHAMM is often overexpressed in tumors and is an independent adverse prognostic factor for a number of cancers such as breast and prostate. Interestingly, pharmacological or genetic inhibition of RHAMM in vitro and in vivo ablates tumor invasiveness and metastatic spread, implicating RHAMM as a potential therapeutic target to restrict tumor growth and improve patient survival. However, RHAMM’s pro-tumor activity is dependent on its subcellular distribution, which complicates the design of RHAMM-directed therapies. An alternative approach is to identify downstream signaling pathways that mediate RHAMM-promoted tumor aggressiveness. Herein, we discuss the pro-tumoral roles of RHAMM and elucidate the corresponding regulators and signaling pathways mediating RHAMM downstream events, with a specific focus on strategies to target the RHAMM signaling network in cancer cells.

RHAMM expression tunes the response of breast cancer cell lines to hyaluronan

Hyaluronan (HA) synthesis and degradation are altered during carcinogenesis leading to an increased HA content in the tumor microenvironment, which correlates with poor prognosis and treatment outcomes. The main HA receptors, CD44 and RHAMM, are also overexpressed in tumors where they activate anti-apoptotic, proliferative, invasive, and migration signaling pathways. Herein, we used a unidirectional HA gradient to investigate in a high-throughput fashion the bi-directional communication between HA and breast cancer cell lines with different surface expression of CD44 and RHAMM. We found that the expression of CD44 and RHAMM depends on the HA density: the expression of these receptors is promoted at higher HA density and RHAMM is more sensitive to these changes when compared to CD44. Blocking either CD44 or RHAMM revealed different functions on binding and recognizing HA and a compensatory expression between these two receptors that maintains protumorigenic effectors such as cortactin. STATEMENT OF SIGNIFICANCE: We show that the expression of main hyaluronan (HA) receptors CD44 and RHAMM is enhanced in a HA concentration-dependent manner. Blocking activity experiments with either RHAMM or CD44 reveal the redundancy of these two receptors towards HA recognition and activation/recruitment of protumorigenic molecular effector, cortactin. These experiments also demonstrate that cells with overexpressed RHAMM are more sensitive to HA density than CD44 positive cells. The reported results are important for the development of therapies that target the hyaluronan signaling in the tumor microenvironment.

Impact of Cancer Stem Cells on Therapy Resistance in Gastric Cancer

Gastric cancer (GC) is the fourth leading cause of cancer death worldwide, with an average 5-year survival rate of 32%, being of 6% for patients presenting distant metastasis. Despite the advances made in the treatment of GC, chemoresistance phenomena arise and promote recurrence, dissemination and dismal prognosis. In this context, gastric cancer stem cells (gCSCs), a small subset of cancer cells that exhibit unique characteristics, are decisive in therapy failure. gCSCs develop different protective mechanisms, such as the maintenance in a quiescent state as well as enhanced detoxification procedures and drug efflux activity, that make them insusceptible to current treatments. This, together with their self-renewal capacity and differentiation ability, represents major obstacles for the eradication of this disease. Different gCSC regulators have been described and used to isolate and characterize these cell populations. However, at the moment, no therapeutic strategy has achieved the effective targeting of gCSCs. This review will focus on the properties of cancer stem cells in the context of therapy resistance and will summarize current knowledge regarding the impact of the gCSC regulators that have been associated with GC chemoradioresistance.

Tumor-Tissue Expression of the Hyaluronic Acid Receptor RHAMM Predicts Histological Transformation in Follicular Lymphoma Patients

Histological transformation (HT) remains the leading cause of mortality in follicular lymphoma (FL), underlining the need to identify reliable transformation predictors. The hyaluronic acid receptors CD44 and the receptor for hyaluronan mediated motility (RHAMM, also known as HMMR and CD168), have been shown to be involved in the pathogeneses of both solid tumors and hematological malignancies. In an attempt to improve risk stratification, expression of RHAMM and CD44 were evaluated by immunohistochemistry and digital image analysis in pre-therapeutic tumor-tissue biopsies from FL patients, either without (nt-FL, n = 34), or with (st-FL, n = 31) subsequent transformation, and in paired biopsies from the transformed lymphomas (tFL, n = 31). At the time of initial diagnosis, samples from st-FL patients had a higher expression of RHAMM compared with samples from nt-FL patients (p < 0.001). RHAMM expression further increased in tFL samples following transformation (p < 0.001). Evaluation of CD44 expression showed no differences in expression comparing nt-FL, st-FL, and tFL samples. Shorter transformation-free survival was associated with high tumoral and intrafollicular RHAMM expression, as well as with low intrafollicular CD44 expression (p = 0.002, p < 0.001, and p = 0.034, respectively). Our data suggest that high tumor-tissue RHAMM expression predicts the risk of shorter transformation-free survival in FL patients already at initial diagnosis.

Targeting Hyaluronic Acid and Peritoneal Dissemination in Colorectal Cancer

Peritoneal metastasis (PM) from colorectal cancer (CRC) carries a significant mortality rate for patients and treatment is challenging. The development of PM is a multistep process involving detachment, adhesion, invasion and colonization of the peritoneal cavity. Cytoreductive surgery and HIPEC (hyperthermic intraperitoneal chemotherapy) for PM from CRC has some benefit but overall survival is poor and recurrence rates are high. Treatments to prevent the development of peritoneal metastasis could have the potential to improve CRC survival and disease-free outcomes. The ability of cancer cells to invade the peritoneum and become established as metastatic tumors is influenced by a multifactorial process. Hyaluronic acid (HA) has been shown to coat the mesothelial cells of the peritoneum and has been demonstrated to be utilized in various malignancies as part of the metastatic process in peritoneal dissemination. CD44, RHAMM (CD168) and ICAM-1 have all been shown to be binding partners for HA. Targeting HA-mediated binding may prevent adhesion to distant sites within the peritoneum through suppression of interaction of these molecules. Here we review the current literature and discuss key molecules involved with PM dissemination, with the potential to target these mechanisms in the delivery of future treatments.

Systematic Analysis of the Clinical Significance of Hyaluronan-Mediated Motility Receptor in Colorectal Cancer

Background: The role of hyaluronan-mediated motility receptor (HMMR) in colorectal cancer (CRC) remains unclear. The present study aimed to explore the association of HMMR with the development and prognosis of CRC using sequence datasets, clinical tissues, blood samples, and cell lines.

Methods: CRC datasets were downloaded from TCGA and GEO databases. Forty CRC tissue samples, 120 CRC blood samples, and 100 healthy controls were collected. Four CRC cell lines (HCT116, HT-29, LoVo, and SW480) and one normal human colon mucosal epithelial cell line (NCM460) were cultured. RT-qPCR was used to determine the expression of HMMR in the tissues and cell lines. ELISA was used to measure HMMR levels in the blood samples.

Results: The expression of HMMR was significantly increased in CRC tissues than in corresponding adjacent tissues based on TCGA and GEO datasets, and clinical CRC tissues. No associations were found between the expression of HMMR and the TNM stage or other clinical parameters. The expression of HMMR varied in different CRC cell lines. The blood levels of HMMR tended to be higher in patients with CRC than in healthy controls. TCGA and GEO datasets showed inconsistent results regarding the association of HMMR expression with the survival of patients with CRC.

Conclusion: The expression of HMMR is increased in CRC tissues but not in the blood. The expression of HMMR is independent of CRC development and has no prognostic significance in patients with CRC.

The Impact of Hyaluronic Acid on Tendon Physiology and Its Clinical Application in Tendinopathies

The physical-chemical, structural, hydrodynamic, and biological properties of hyaluronic acid within tendons are still poorly investigated. Medical history and clinical applications of hyaluronic acid for tendinopathies are still debated. In general, the properties of hyaluronic acid depend on several factors including molecular weight. Several preclinical and clinical experiences show a good efficacy and safety profile of hyaluronic acid, despite the absence of consensus in the literature regarding the classification according to molecular weight. In in vitro and preclinical studies, hyaluronic acid has shown physical-chemical properties, such as biocompatibility, mucoadhesivity, hygroscopicity, and viscoelasticity, useful to contribute to tendon healing. Additionally, in clinical studies, hyaluronic acid has been used with promising results in different tendinopathies. In this narrative review, findings encourage the clinical application of HA in tendinopathies such as rotator cuff, epicondylitis, Achilles, and patellar tendinopathy.

AR-mTOR-SRF Axis Regulates HMMR Expression in Human Prostate Cancer Cells

The elevated expression of the hyaluronan-mediated motility receptor (HMMR) is known to be highly associated with tumor progression in prostate cancer, but the molecular mechanisms underlying the regulation of HMMR expression remain unclear. Here, we report that mammalian target of rapamycin (mTOR) is a key regulator of HMMR expression, for which its kinase activity is required. Pharmacological inhibitors of mTOR, such as rapamycin and Torin2, markedly suppressed the mRNA level as well as the protein level of HMMR in LNCaP and PC-3 cells. Our data demonstrate that such regulation occurs at the transcription level. HMMR promoter reporter assays revealed that the transcription factor SRF is responsible for the mTOR-mediated transcriptional regulation of HMMR gene. Consistently, the suppression of HMMR expression by Torin2 was noticeably reversed by the overexpression of SRF. Moreover, our findings suggest that the SRF binding sites responsible for the transcriptional regulation of HMMR through the mTOR-SRF axis are located in HMMR promoter sequences carrying the first intron, downstream of the translational start site. Furthermore, the upregulation of HMMR by DHT was abolished by stimulation with rapamycin, prior to DHT treatment, suggesting that mTOR activity is required for the induction of HMMR expression by androgen. Collectively, our study provides new mechanistic insights into the role of mTOR/SRF/AR signaling in HMMR regulation in prostate cancer cells.

RHAMM in liver metastases of stage IV colorectal cancer with mismatch-repair proficient status correlates with tumor budding, cytotoxic T-cells and PD-1/PD-L1

BACKGROUND

During the last decades, the management for metastatic colorectal cancer patients has improved due to novel therapeutic approaches. A mismatch-repair deficient status seems to favour a better response to checkpoint inhibitor therapy, but the question arises whether a specific subgroup of stage IV patients with mismatch-repair (MMR) proficient status should also be considered. RHAMM (Receptor for Hyaluronic Acid Mediated Motility/HAMMR/CD168) is characterized by tumor progression and immunogenicity. Therefore, the aim of this study is to determine whether RHAMM within the CRLM of MMR-proficient patients correlate with a more immunological microenvironment, represented by cytotoxic T-cells, PD-1 and PD-1.

METHODS

Two patient cohorts of liver metastases from MMR colorectal cancers were included into the study (n = 81 and 76) using ngTMA® technology and immunohistochemically analyzed for RHAMM, cytotoxic T-cells (CD8+), PD-1/PD-L1, intrametastatic budding (IMB) and perimetastatic budding (PMB).

RESULTS

RHAMM-positive IMB was linked to a higher PD-L1 expression (r = 0.32; p = 0.233 and r = 0.28; p = 0.044) in the center and periphery of the metastasis and RHAMM-positive PMB was associated with a higher expression of PD-1 (r = 0.33; p = 0.0297), and especially PD-L1 (r = 0.604; p < 0.0001 and r = 0.43; p = 0.003) in the center and periphery of the metastasis. IMB and PMB were additionally associated with a higher count of CD8+ T-cells (p < 0.0001; r = 0.58; p < 0.0001; r = 0.53).

CONCLUSIONS

The RHAMM status can be assessed in IMB/PMB either in biopsies or in resections of colorectal cancer liver metastases. A positive RHAMM status in IMB and/or PMB may be a potential indicator for a checkpoint inhibitor therapy for stage IV colorectal cancer patients with MMR proficient status.

Hyaluronic acid-doxorubicin nanoparticles for targeted treatment of colorectal cancer

Colorectal cancer, common in both men and women, occurs when tumors form in the linings of the colon. Common treatments of colorectal cancer include surgery, chemotherapy, and radiation therapy; however, many colorectal cancer treatments often damage healthy tissues and cells, inducing severe side effects. Conventional chemotherapeutic agents such as doxorubicin (Dox) can be potentially used for the treatment of colorectal cancer; however, they suffer from limited targeting and lack of selectivity. Here, we report that doxorubicin complexed to hyaluronic acid (HA) (HA-Dox) exhibits an unusual behavior of high accumulation in the intestines for at least 24 hr when injected intravenously. Intravenous administrations of HA-Dox effectively preserved the mucosal epithelial intestinal integrity in a chemical induced colon cancer model in mice. Moreover, treatment with HA-Dox decreased the expression of intestinal apoptotic and inflammatory markers. The results suggest that HA-Dox could effectively inhibit the development of colorectal cancer in a safe manner, which potentially be used a promising therapeutic option.

pH-responsive hyaluronic acid-based nanoparticles for targeted curcumin delivery and enhanced cancer therapy

Curcumin (CUR) display promising antitumor effects, however, the poor water solubility severely limited its clinical application. To overcome this problem, polymeric nanocarriers have been adopted for targeted CUR delivery and enhanced cancer therapy. In this paper, utilizing an acid-labile hydrazone linkage, hydrophobic CUR was conjugated with hydrophilic hyaluronic acid (HA) to form amphiphilic HA-ADH-CUR conjugates, which could subsequently self-assemble to form nanoparticles (HA@CUR NPs) in aqueous. The in vitro drug release experiments showed that HA@CUR NPs exhibited a pH-responsive CUR release behavior, and the release rate of CUR was 73.5 % in pH 5.0. Further, in vitro cell experiments showed HA@CUR NPs could be efficiently internalized by 4T1 and MCF-7 cancer cells through CD44 receptor mediated endocytosis and successfully release CUR in acidic lysosome environment for chemotherapy. In vivo antitumor experiments showed that, compared to free CUR, HA@CUR NPs could efficiently cumulate in tumor site via EPR effect and CD44 mediated endocytosis, achieve superior therapeutic effect for tumor growth suppression. Therefore, HA@CUR NPs were a highly promising nanocarrier for hydrophobic CUR to realize enhanced cancer therapy with good biosafety.

Identification of the association between HMMR expression and progression of hepatocellular carcinoma via construction of a co-expression network

The aim of the present study was to identify key genes involved in the progression of hepatocellular carcinoma (HCC). According to the theory of the multistep process of hepatocarcinogenesis and weighted gene co-expression network analysis, hub genes associated with the progression of HCC were identified using the gene expression profiles of patients with normal to chronic hepatitis/cirrhosis and dysplastic nodules to HCC. An independent dataset was used to verify the association between hub gene and clinical phenotype. The diagnostic and prognostic value of hub genes regarding HCC were evaluated. Gene set enrichment analysis (GSEA) was performed to explore the function of hub genes. A co-expression gene module positively associated with HCC progression was identified. Combined with a protein-protein interaction (PPI) network, a total of 10 common hub genes common to both the module of interest and the PPI network were selected as hub genes. Hyaluronan mediated motility receptor (HMMR) was selected as the candidate gene and was significantly upregulated in HCC at the mRNA and protein expression levels. HMMR is a promising diagnostic biomarker for HCC, and is also associated with its progression. The expression of HMMR was positively correlated with HCC tumor grade, pathological stage, tumor stage and Ishak score. The expression of HMMR was an independent prognostic factor compared with clinicopathological features. Patients with high expression levels of HMMR exhibited a less favorable prognosis. GSEA identified 6 representative gene sets that were associated with cancer. Overall, HMMR may serve an important role in HCC and may have potential as a biomarker of HCC diagnosis and progression.

Bioinformatics Analysis of Prognostic miRNA Signature and Potential Critical Genes in Colon Cancer

This study aims to lay a foundation for studying the regulation of microRNAs (miRNAs) in colon cancer by applying bioinformatics methods to identify miRNAs and their potential critical target genes associated with colon cancer and prognosis. Data of differentially expressed miRNAs (DEMs) and genes (DEGs) downloaded from two independent databases (TCGA and GEO) and analyzed by R software resulted in 472 DEMs and 565 DEGs in colon cancers, respectively. Next, we developed an 8-miRNA (hsa-mir-6854, hsa-mir-4437, hsa-mir-216a, hsa-mir-3677, hsa-mir-887, hsa-mir-4999, hsa-mir-34b, and hsa-mir-3189) prognostic signature for patients with colon cancer by Cox proportional hazards regression analysis. To predict the target genes of these miRNAs, we used TargetScan and miRDB. The intersection of DEGs with the target genes predicted for these eight miRNAs retrieved 112 consensus genes. GO and KEGG pathway enrichment analyses showed these 112 genes were mainly involved in protein binding, one-carbon metabolic process, nitrogen metabolism, proteoglycans in cancer, and chemokine signaling pathways. The protein-protein interaction network of the consensus genes, constructed using the STRING database and imported into Cytoscape, identified 14 critical genes in the pathogenesis of colon cancer (CEP55, DTL, FANCI, HMMR, KIF15, MCM6, MKI67, NCAPG2, NEK2, RACGAP1, RRM2, TOP2A, UBE2C, and ZWILCH). Finally, we verified the critical genes by weighted gene co-expression network analysis (WGCNA) of the GEO data, and further mined the core genes involved in colon cancer. In summary, this study identified an 8-miRNA model that can effectively predict the prognosis of colon cancer patients and 14 critical genes with vital roles in colon cancer carcinogenesis. Our findings contribute new ideas for elucidating the molecular mechanisms of colon cancer carcinogenesis and provide new therapeutic targets and biomarkers for future treatment and prognosis.

Galectin-3 Interacts with C/EBPβ and Upregulates Hyaluronan-Mediated Motility Receptor Expression in Gastric Cancer

The hyaluronan-mediated motility receptor (HMMR) is overexpressed in gastric cancer; however, the apparent role of HMMR has not been well defined owing to lack of detailed studies on gastric tumorigenesis. Therefore, we elucidated the functional and regulatory mechanisms of HMMR in gastric cancer. Using publicly available data, we confirmed HMMR overexpression in patients with gastric cancer. HMMR silencing decreased proliferation, migration, and invasion of gastric cancer cells, whereas HMMR overexpression reversed these effects. A gastric cancer xenograft mouse model showed statistically significant inhibition of tumor growth upon HMMR depletion. Previous data from cDNA microarray showed reduced HMMR expression upon inhibition of galectin-3. However, overexpression of galectin-3 increased HMMR expression, cell proliferation, and motility in gastric cancer cells, whereas HMMR silencing blocked these effects. Interestingly, galectin-3 interacted directly with C/EBPβ and bound to HMMR promoter to drive its transcription, and gastric cancer cell proliferation and motility. Altogether, high expression of HMMR promoted gastric cancer cell proliferation and motility and could be a prognostic factor in gastric cancer. In addition, HMMR expression was regulated by the interaction between C/EBPβ and galectin-3. Therefore, targeting HMMR along with galectin-3 and C/EBPβ complex could be a potential treatment strategy for inhibiting gastric cancer progression and metastasis. IMPLICATIONS: This study provides evidence that galectin-3 interacts with C/EBPβ in gastric cancer, and galectin-3 and C/EBPβ complex promotes gastric cancer cell progression and motility through upregulating HMMR expression.

Interaction between laminin-5γ2 and integrin β1 promotes the tumor budding of colorectal cancer via the activation of Yes-associated proteins

Colorectal cancer (CRC) is a common cancer type and a threat to human health. Tumor budding (TB) is the presence of a single cancer cell or clusters of up to five cancer cells prior to the invasive front of an aggressive carcinoma and is an independent prognosis factor for CRC. The molecular mechanism of TB is still unclear, and drugs that inhibit this process are still in the blank stage. This study found that TBs exhibit characteristics of partial EMT with a decreased expression of E-cadherin and no substantial differences in the expression of N-cadherin and vimentin. We also observed the interaction of integrin with extracellular matrix components, laminin-5γ2 (LN-5γ2), play essential roles in the TB of CRC. We then verified that the interaction between LN-5γ2 and integrin β1 promotes the TB of CRC via the activation of FAK and Yes-associated proteins (YAP). A natural drug monomer, cucurbitacin B, was screened using virtual screening methods for the interaction interface of proteins. We found that this monomer could block the interaction interface between LN-5γ2 and integrin β1 and substantially inhibit the TB of CRC cells via inactivation of YAP. This study provides new insights into the mechanism of TB mechanism and the development of drugs targeting the TB of CRC.

Systematic screening of protein-coding gene expression identified HMMR as a potential independent indicator of unfavorable survival in patients with papillary muscle-invasive bladder cancer

Papillary and non-papillary are two histological patterns of bladder carcinogenesis and are considered as dual-track oncogenic pathways, which have different genetic alterations. The TCGA-bladder cancer (BLCA) database contains clinicopathological, genomic and survival data from over 400 muscle-invasive bladder cancer patients. In this study, using data from this database, we performed a systematic screening of gene expression to identify the protein-coding gene that might have prognostic value in papillary and non-papillary muscle-invasive bladder cancer (MIBC). The data of patients with primary MIBC in TCGA-BLCA was acquired from the UCSC Xena project (http://xena.ucsc.edu) for re-analysis. By setting |log2 fold change|≥2 and adjusted p value <0.01 as the screening criteria, we found 751 significantly dysregulated genes, including 183 overexpressed and 568 downregulated genes. HMMR was identified as a potential prognostic marker with unique expression. Multivariate analysis showed that its expression was an independent prognostic indicator of shorter progression-free survival (PFS) (HR: 1.400, 95%CI: 1.021-1.920, p = 0.037) in the papillary subtype. ENST00000393915.8 and ENST00000358715.3, two transcripts that contain all 18 exons and encode the full length of HMMR, were significantly upregulated in cancer tissues compared with normal bladder tissues. None of the 17 CpG sites in its DNA locus was relevant to HMMR expression. 26/403 (6.5%) MIBC cases had HMMR gene-level amplification, which was associated with upregulated HMMR expression compared with the copy-neutral and deletion groups. Gene set enrichment analysis (GSEA) in papillary MIBC found that the high HMMR expression group was associated with upregulated genes enriched in multiple gene sets with well-established role in BC development, including G2M checkpoint, E2 F Targets, Myc Targets V1, Myc Targets V2 and Glycolysis. Based on these findings, we infer that HMMR expression might be a specific prognostic marker in terms of PFS in papillary MIBC. DNA amplification might be an important mechanism of its elevation.

A Robust 8-Gene Prognostic Signature for Early-Stage Non-small Cell Lung Cancer

Background: The current staging system is imprecise for prognostic prediction of early-stage non-small cell lung cancer (NSCLC). This study aimed to develop a robust prognostic signature for early-stage NSCLC, allowing classification of patients with a high risk of poor outcome and specific treatment decision. Method: In the present study, a comprehensive genome-wide profiling analysis was conducted using a retrospective pool of early-stage NSCLC patient data from the previous datasets of Gene Expression Omnibus (GEO) including GSE31210, GSE37745, and GSE50081 and The Cancer Genome Atlas (TCGA). Cox proportional hazards models were implemented to determine the association between gene expression levels and overall patient survival in each dataset. The common genes among all datasets were selected as candidate prognostic genes. A risk score model was developed and validated using four independent datasets and the entire cohort. The Kaplan-Meier with log-rank test was used to assess survival difference. Results: A univariate Cox proportional hazards regression analysis for each dataset showed that a total of 2280 genes in GSE31210, 762 genes in GSE37745, 871 genes in GSE50081, and 666 genes in TCGA were identified as candidate protective genes, while overall 2131 genes in GSE31210, 913 in GSE37745, 1107 in GSE50081, and 997 in TCGA were identified as candidate risky genes. There were 8 common genes associated with overall survival, including 7 mRNA and 1 lncRNA. By using the Step-wise multivariate Cox analysis, an 8-gene prognostic signature (CDCP1, HMMR, TPX2, CIRBP, HLF, KBTBD7, SEC24B-AS1, and SH2B1) for early-stage NSCLC was developed. Patients in the high-risk group had shorter overall survival than those in the low-risk group. Multivariate regression and stratified analysis suggested that the prognostic power of the 8-gene signature was independent of other clinical factors. Furthermore, the 8-gene signature achieved AUC values of 0.726, 0.701, 0.725 and 0.650 in GSE31210, GSE37745, GSE50081 and TCGA, respectively. Moreover, the combination of the 8-gene signature and the stage resulted to a better patient classification for survival prediction and treatment decision. Conclusion: This study developed a robust gene signature with great value for prognostic prediction in early-stage NSCLC, which may contribute to patient classification and personalized treatment decisions.

Hyaluronan-mediated motility receptor confers resistance to chemotherapy via TGFβ/Smad2-induced epithelial-mesenchymal transition in gastric cancer

Chemotherapy is one of the vital treatments for gastric cancer (GC) patients, especially those suffering advanced stages. Chemoresistance results in tumor relapse, leading to poor prognosis in GC patients; thus, identifying key regulators in this process might provide novel clues for GC therapy. Herein, we identify hyaluronan-mediated motility receptor (HMMR) as a key regulator of chemoresistance in GC. HMMR was found to be substantially up-regulated in 5-fluorouracil (5-Fu)-resistant GC biopsies and cell lines. High expression of HMMR significantly correlates with tumor relapse and predicts poorer prognosis in GC patients. Moreover, we observed that HMMR induced epithelial-mesenchymal transition and increased the cancer stem cell properties of GC, thus rendering resistance to chemotherapy. Importantly, silencing of HMMR effectively increased the susceptibility to 5-Fu therapy both in vitro and in vivo. Furthermore, we demonstrated that HMMR activates the TGF-β/Smad2 signaling pathway, which was required for the HMMR-mediated oncogenic effects and exhibited significant clinical relevance with HMMR expression. These findings reveal a critical role for HMMR in the chemoresistance of GC and suggest that HMMR might be a potential prognostic marker or therapeutic target against the disease.-Zhang, H., Ren, L., Ding, Y., Li, F., Chen, X., Ouyang, Y., Zhang, Y., Zhang, D. Hyaluronan-mediated motility receptor confers resistance to chemotherapy via TGFβ/Smad2-induced epithelial-mesenchymal transition in gastric cancer.

Identification of several cell cycle relevant genes highly correlated with the progression and prognosis of human bladder urothelial tumor

The incidence of bladder cancer (BCa) in China is the highest among genitourinary system tumors, and its progression is affected by multitudinous pathways, of which cell cycle progress plays an important role. This study screened and enriched differentially expressed genes (DEGs) from four gene expression profiles using bioinformatics analysis methods. The enrichment and analysis of gene function showed that these genes were highly correlated with cell cycle regulation. Identification of candidate small molecules was conducted to evaluate the application of clinical transformation in these DEGs. Prognostic and stage-related expression analysis further sorted five highly expressed genes associated with worse prognosis and higher stages in patients with BCa. Further analysis revealed their interaction in cell cycle regulation and genetical alteration. Meanwhile, we validated the elevated expression of these genes through transcription and translation levels. Taking the results together, we could infer that these five genes are valuable in diagnosis, prediction, and providing candidate therapeutic targets for patients with BCa in different stages.

Immunohistochemical analysis of RHAMM expression in normal and neoplastic human tissues: a cell cycle protein with distinctive expression in mitotic cells and testicular germ cells

Expression of Receptor for Hyaluronic Acid Mediated Motility (RHAMM) increases cellular motility and RHAMM overexpression promotes invasive phenotype and metastasis of cancer cells. RHAMM has been suggested as a biomarker for poor prognosis in several tumor types, including lung, breast, colorectal, gastric, pancreatic ductal, and ovarian cancers. RNA studies showed restricted RHAMM expression in normal tissues, but its protein expression data in tissues were limited. In light of its potential as a prognostic marker and a therapeutic target, we performed immunohistochemical analysis to systematically characterize RHAMM expression in normal and neoplastic human tissues. Among 29 normal adult tissues, RHAMM protein showed restricted expression and was observed in the thymus, lymph node/tonsil, small intestine, colon, skin, bone marrow, placenta, and testis. The cellular distribution patterns of RHAMM in these normal tissues were consistent with RHAMM being a G2/M cell cycle protein, and this was further supported in comparison to the expression of cyclin B2, another G2/M protein. However, unlike the subcellular localization of cyclin B2, RHAMM decorated mitotic spindles in both anaphase and metaphase. RHAMM expression in tumor tissues is variable; and higher RHAMM protein expression is associated with histologically higher-grade tumors in general. Distinct from its expression in somatic tissues, RHAMM showed diffuse, strong, stage-specific expression in the spermatocyte stage of germ cells in adult testis. The neoplastic counterpart, spermatocytic tumor, also showed strong RHAMM expression. This unique expression in testis suggests that RHAMM may function during normal testicular germ cell maturation.

Integrated Genomic and Immunophenotypic Classification of Pancreatic Cancer Reveals Three Distinct Subtypes with Prognostic/Predictive Significance

Purpose: Current clinical classification of pancreatic ductal adenocarcinoma (PDAC) is unable to predict prognosis or response to chemo- or immunotherapy and does not take into account the host reaction to PDAC cells. Our aim is to classify PDAC according to host- and tumor-related factors into clinically/biologically relevant subtypes by integrating molecular and microenvironmental findings.Experimental Design: A well-characterized PDAC cohort (n = 110) underwent next-generation sequencing with a hot spot cancer panel while next-generation tissue microarrays were immunostained for CD3, CD4, CD8, CD20, PD-L1, p63, hyaluronan-mediated motility receptor (RHAMM), and DNA mismatch repair proteins. Previous data on FOXP3 were integrated. Immune cell counts and protein expression were correlated with tumor-derived driver mutations, clinicopathologic features (TNM 8th edition, 2017), survival, and epithelial-mesenchymal transition (EMT)-like tumor budding.Results: Three PDAC subtypes were identified: the "immune escape" (54%), poor in T and B cells and enriched in FOXP3⁺ regulatory T cells (Treg), with high-grade budding, frequent CDKN2A, SMAD4, and PIK3CA mutations, and poor outcome; the "immune rich" (35%), rich in T and B cells and poorer in FOXP3⁺ Tregs, with infrequent budding, lower CDKN2A and PIK3CA mutation rate, and better outcome and a subpopulation with tertiary lymphoid tissue (TLT), mutations in DNA damage response genes (STK11 and ATM), and the best outcome; and the "immune exhausted" (11%), with immunogenic microenvironment and two subpopulations-one with PD-L1 expression and a high PIK3CA mutation rate and a microsatellite-unstable subpopulation with a high prevalence of JAK3 mutations. The combination of low budding, low stromal FOXP3 counts, presence of TLTs, and absence of CDKN2A mutations confers significant survival advantage in patients with PDAC.Conclusions: Immune host responses correlate with tumor characteristics, leading to morphologically recognizable PDAC subtypes with prognostic/predictive significance. Clin Cancer Res; 24(18); 4444-54. ©2018 AACRSee related commentary by Khalil and O'Reilly, p. 4355.

Transcriptional landscape of human cancers

The homogeneity and heterogeneity in somatic mutations, copy number alterations and methylation across different cancer types have been extensively explored. However, the related exploration based on transcriptome data is lacking. In this study we explored gene expression profiles across 33 human cancer types using The Cancer Genome Atlas (TCGA) data. We identified consistently upregulated genes (such as E2F1, EZH2, FOXM1, MYBL2, PLK1, TTK, AURKA/B and BUB1) and consistently downregulated genes (such as SCARA5, MYOM1, NKAPL, PEG3, USP2, SLC5A7 and HMGCLL1) across various cancers. The dysregulation of these genes is likely to be associated with poor clinical outcomes in cancer. The dysregulated pathways commonly in cancers include cell cycle, DNA replication, repair, and recombination, Notch signaling, p53 signaling, Wnt signaling, TGFβ signaling, immune response etc. We also identified genes consistently upregulated or downregulated in highly-advanced cancers compared to lowly-advanced cancers. The highly (low) expressed genes in highly-advanced cancers are likely to have higher (lower) expression levels in cancers than in normal tissue, indicating that common gene expression perturbations drive cancer initiation and cancer progression. In addition, we identified a substantial number of genes exclusively dysregulated in a single cancer type or inconsistently dysregulated in different cancer types, demonstrating the intertumor heterogeneity. More importantly, we found a number of genes commonly dysregulated in various cancers such as PLP1, MYOM1, NKAPL and USP2 which were investigated in few cancer related studies, and thus represent our novel findings. Our study provides comprehensive portraits of transcriptional landscape of human cancers.

Role of Pericellular Matrix in the Regulation of Cancer Stemness

Cancer stem cells (CSC) are a prominent component of the tumor bulk and extensive research has now identified them as the subpopulation responsible for tumor relapse and resistance to anti-cancer treatments. Surrounding the bulk formed of tumor cells, an extracellular matrix contributes to cancer growth; the main component of the tumor micro-environment is hyaluronan, a large disaccharide forming a molecular network surrounding the cells. The hyaluronan-dependent coat can regulate cell division and motility in cancer progression and metastasis. One of the receptors of hyaluronan is CD44, a surface protein frequently used as a CSC marker. Indeed, tumor cells with high levels of CD44 appear to exhibit CSC properties and are characterized by elevated relapse rate. The CD44-hyaluronan-dependent interactions are Janus-faced: on one side, they have been shown to be crucial in both malignancy and resistance to therapy; on the other, they represent a potential value for future therapies, as disturbing the CD44-hyaluronan axis would not only impair the pericellular matrix but also the subpopulation of self-renewing oncogenic cells. Here, we will review the key roles of HA and CD44 in CSC maintenance and propagation and will show that CSC-like spheroids from a rabdhomyosarcoma cell line, namely RD, have a prominent pericellular coat necessary for sphere formation and for elevated migration. Thus, a better understanding of the hyaluronan-CD44 interactions holds the potential for ameliorating current cancer therapies and eradicating CSC.

Increased RHAMM expression relates to ovarian cancer progression

BACKGROUND

Elevated hyaluronan-mediated motility receptor (RHAMM) has been reported to contribute to disease progression, aggressive phenotype and poor prognosis in multiple cancer types, however, RHAMM's role in ovarian cancer (OC) has not been elucidated. Therefore, we sought to evaluate the role for RHAMM in epithelial OC.

RESULTS

Despite little to no expression in normal ovarian surface epithelium, western immunoblotting, immunohistochemical staining and enzyme linked immunosorbent assay showed elevated RHAMM levels in clinical tissue sections, omental metastasis and urine specimens of serous OC patients, as well as in cell lysates. We also found that RHAMM levels increase with increasing grade and stage in serous OC tissues and that RHAMM localizes to the apical cell surface and inclusion cysts. Apical localization of RHAMM suggested protein secretion which was validated by detection of significantly elevated urinary RHAMM levels (p < 0.0001) in OC patients (116.66 pg/mL) compared with normal controls (8.16 pg/mL). Likewise, urinary RHAMM levels decreased following cytoreductive surgery in OC patients suggesting the source of urinary RHAMM from tumor tissue. Lastly, we validated RHAMM levels in OC cell lysate and found at least 12× greater levels compared to normal ovarian surface epithelial cells.

CONCLUSION

This pilot study shows, for the first time, that RHAMM may contribute to OC disease and could potentially be used as a prognostic marker.

The hyaluronan-mediated motility receptor RHAMM promotes growth, invasiveness and dissemination of colorectal cancer

In colorectal cancer (CRC), RHAMM is an independent adverse prognostic factor. The aim of the study was therefore to investigate on the role of RHAMM as a potential direct driver of cell proliferation and migration in CRC cell lines and to identify pathways dependent on RHAMM in human CRC.

Proliferation, cell cycle alterations and invasive capacity were tested in two RHAMM- and control- knockdown CRC cell lines by flow cytometry and in vitro assays. Tumorigenicity and metastasis formation was assessed in immunodeficient mice. RNA-Seq and immunohistochemistry was performed on six RHAMM+/- primary CRC tumors.

In vitro, silencing of RHAMM inhibited CRC cell migration and invasion by 50% (p<0.01). In vivo, RHAMM knockdown resulted in slower growth, lower tumor size (p<0.001) and inhibition of metastasis (p<0.001). Patients with RHAMM-high CRC had a worse prognosis (p=0.040) and upregulated pathways for cell cycle progression and adhesion turnover.

RHAMM overexpression is correlated with increased migration and invasion of CRC cells, leads to larger, fast growing tumors, and its downregulation essentially abolishes metastasis in mouse models. RHAMM is therefore a promising therapeutic target in all CRC stages as its inhibition affects growth and dissemination of the primary CRC as well as the metastases.

Redox Responsive Hyaluronic Acid Nanogels for Treating RHAMM (CD168) Over-expressive Cancer, both Primary and Metastatic Tumors

It remains a substantial challenge to targetedly deliver drug to both primary tumors and metastatic lesions employing a single nanoparticle delivery system. Here aiming at the receptor for hyaluronic acid mediated motility (RHAMM or CD168), a specific receptor for hyaluronic acid (HA), the bioreductive responsive HA nanogels loaded doxorubicin were prepared. The targeting effects of HA nanogels in high RHAMM-expressed cancer cells, primary and metastatic tumors were investigated. It was found that HA nanogels show a strong in vitro and in vivo RHAMM-mediated cellular uptake and drug delivery. The cellular uptake of HA nanogels in high RHAMM-expressed LNCaP and H22 cells was far more than the uptake in low RHAMM-expressed NIH3T3 cells. The IC50 value of drug-loaded HA nanogels against H22 cells was lower than that of free drug. In vivo antitumor activity examinations showed that the HA nanogels not only had significantly superior antitumor efficacy in murine H22 and human LNCaP tumor-bearing mice but also exhibited much deep tumor penetration. The drug delivery of lymph node metastasis by systemically administering HA nanogels demonstrated that the HA nanogels could sufficiently increase drug concentration in metastatic lymph node by RHAMM-HA interaction and inhibit the growth of metastatic lymph node, even completely heal malignant lymph node metastasis. Thus, RHAMM-directed drug delivery is a promising therapy route for treating both primary and metastatic tumors.

HMMR antisense RNA 1, a novel long noncoding RNA, regulates the progression of basal-like breast cancer cells

Recently, accumulating evidence has suggested that long noncoding RNAs (lncRNAs) play crucial roles in carcinogenesis and cancer progression. Hyaluronan-mediated motility receptor (HMMR) is an essential cancer-related gene in basal-like breast cancer (BLBC). In our study, HMMR antisense RNA 1 (HMMR-AS1) was analyzed in BLBC patients through polymerase chain reaction analysis. Here, we found that the expression of HMMR was positively correlated with HMMR-AS1 (RP11-80G.1). When HMMR-AS1 (RP11-80G.1) was knocked down, the expression of HMMR markedly reduced. Furthermore, in MDA-MB-231 and MDA-MB-468 breast cancer cells, the proliferation and migration abilities were remarkably suppressed via knocking down HMMR-AS1 (RP11-80G.1) in vitro. The results showed that lncRNA HMMR-AS1 (RP11-80G.1) influenced the progression of BLBCs through regulating HMMR, suggesting that HMMR-AS1 (RP11-80G.1) could be regarded as a novel biomarker and therapeutic target in the treatment of BLBCs in future.

Carcinoma Cell Hyaluronan as a "Portable" Cancerized Prometastatic Microenvironment

Hyaluronan (HA) is a structurally simple polysaccharide, but its ability to act as a template for organizing pericellular matrices and its regulated synthesis and degradation are key to initiating repair responses. Importantly, these HA functions are usurped by tumor cells to facilitate progression and metastasis. Recent advances have identified the functional complexities associated with the synthesis and degradation of HA-rich matrices. Three enzymes synthesize large HA polymers while multiple hyaluronidases or tissue free radicals degrade these into smaller bioactive fragments. A family of extracellular and cell-associated HA-binding proteins/receptors translates the bioinformation encrypted in this complex polymer mixture to activate signaling networks required for cell survival, proliferation, and migration in an actively remodeling microenvironment. Changes in HA metabolism within both the peritumor stroma and parenchyma are linked to tumor initiation, progression, and poor clinical outcome. We review evidence that metastatic tumor cells must acquire the capability to autonomously synthesize, assemble, and process their own "portable" HA-rich microenvironments to survive in the circulation, metastasize to ectopic sites, and escape therapeutic intervention. Strategies to disrupt the HA machinery of primary tumor and circulating tumor cells may enhance the effectiveness of current conventional and targeted therapies. Cancer Res; 76(9); 2507-12. ©2016 AACR.

Upregulation of hyaluronan-mediated motility receptor in hepatocellular carcinoma predicts poor survival

Hepatocellular carcinoma (HCC) is one of the most common types of cancer across the world. Hyaluronic acid (HA) has been reported to serve an important role in tumor extension, progression, migration and invasion. In addition, the receptor for HA-mediated motility (RHAMM) has been demonstrated to be overexpressed in different types of cancer. However, whether the upregulation of RHAMM contributes to hepatocarcinogenesis of HCC remains unclear. The present study examined the RHAMM expression in 187 HCC patients by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). RHAMM expression was significantly upregulated in liver cancer tissues compared with that observed in adjacent normal liver tissues. The IHC analysis demonstrated that RHAMM was overexpressed in 18 (72.0%) of the 25 HCC tissues. Furthermore, overexpression of RHAMM was associated with tumor-node-metastasis (TNM), the presence of vascular invasion and recurrence. Notably, the present study indicated that the overexpression of RHAMM was closely associated with the shorter disease-free and overall survival, so it may be a potential independent predictor for disease-free and overall survival of HCC patients. In conclusion, the upregulation of RHAMM is associated with HCC progression and prognosis; and it may be a potential independent predictor of disease-free and overall survival of HCC following surgical resection.