Prognostic role of podocalyxin-like protein expression in various cancers: A systematic review and meta-analysis

CNS/PNS proteoglycans functionalize neuronal and astrocyte niche microenvironments optimizing cellular activity by preserving membrane polarization dynamics, ionic microenvironments, ion fluxes, neuronal activation, and network neurotransductive capacity

Central and peripheral nervous system (CNS/PNS) proteoglycans (PGs) have diverse functional roles, this study examined how these control cellular behavior and tissue function. The CNS/PNS extracellular matrix (ECM) is a dynamic, responsive, highly interactive, space-filling, cell supportive, stabilizing structure maintaining tissue compartments, ionic microenvironments, and microgradients that regulate neuronal activity and maintain the neuron in an optimal ionic microenvironment. The CNS/PNS contains a high glycosaminoglycan content (60% hyaluronan, HA) and a diverse range of stabilizing PGs. Immobilization of HA in brain tissues by HA interactive hyalectan PGs preserves tissue hydration and neuronal activity, a paucity of HA in brain tissues results in a pro-convulsant epileptic phenotype. Diverse CS, KS, and HSPGs stabilize the blood-brain barrier and neurovascular unit, provide smart gel neurotransmitter neuron vesicle storage and delivery, organize the neuromuscular junction basement membrane, and provide motor neuron synaptic plasticity, and photoreceptor and neuron synaptic functions. PG-HA networks maintain ionic fluxes and microgradients and tissue compartments that contribute to membrane polarization dynamics essential to neuronal activation and neurotransduction. Hyalectans form neuroprotective perineuronal nets contributing to synaptic plasticity, memory, and cognitive learning. Sialoglycoprotein associated with cones and rods (SPACRCAN), an HA binding CSPG, stabilizes the inter-photoreceptor ECM. HSPGs pikachurin and eyes shut stabilize the photoreceptor synapse aiding in phototransduction and neurotransduction with retinal bipolar neurons crucial to visual acuity. This is achieved through Laminin G motifs in pikachurin, eyes shut, and neurexins that interact with the dystroglycan-cytoskeleton-ECM-stabilizing synaptic interconnections, neuronal interactive specificity, and co-ordination of regulatory action potentials in neural networks.

Prospects and challenges of CAR-T in the treatment of ovarian cancer

Ovarian cancer ranks as the seventh most prevalent cancer among women and is considered the most lethal gynecological malignancy on a global scale. The absence of reliable screening techniques, coupled with the insidious onset of nonspecific symptoms, often results in a delayed diagnosis, typically at an advanced stage characterized by peritoneal involvement. Management of advanced tumors typically involves a combination of chemotherapy and cytoreductive surgery. However, the therapeutic arsenal for ovarian cancer patients remains limited, highlighting the unmet need for precise, targeted, and sustained-release pharmacological agents. Genetically engineered T cells expressing chimeric antigen receptors (CARs) represent a promising novel therapeutic modality that selectively targets specific antigens, demonstrating robust and enduring antitumor responses in numerous patients. CAR T cell therapy has exhibited notable efficacy in hematological malignancies and is currently under investigation for its potential in treating various solid tumors, including ovarian cancer. Currently, numerous researchers are engaged in the development of novel CAR-T cells designed to target ovarian cancer, with subsequent evaluation of these candidate cells in preclinical studies. Given the ability of chimeric antigen receptor (CAR) expressing T cells to elicit potent and long-lasting anti-tumor effects, this therapeutic approach holds significant promise for the treatment of ovarian cancer. This review article examines the utilization of CAR-T cells in the context of ovarian cancer therapy.

A tumor-restricted glycoform of podocalyxin is a highly selective marker of immunologically cold high-grade serous ovarian carcinoma

Introduction

Targeted-immunotherapies such as antibody-drug conjugates (ADC), chimeric antigen receptor (CAR) T cells or bispecific T-cell engagers (eg, BiTE®) all aim to improve cancer treatment by directly targeting cancer cells while sparing healthy tissues. Success of these therapies requires tumor antigens that are abundantly expressed and, ideally, tumor specific. The CD34-related stem cell sialomucin, podocalyxin (PODXL), is a promising target as it is overexpressed on a variety of tumor types and its expression is consistently linked to poor prognosis. However, PODXL is also expressed in healthy tissues including kidney podocytes and endothelia. To circumvent this potential pitfall, we developed an antibody, named PODO447, that selectively targets a tumor-associated glycoform of PODXL. This tumor glycoepitope is expressed by 65% of high-grade serous ovarian carcinoma (HGSOC) tumors.

Methods

In this study we characterize these PODO447-expressing tumors as a distinct subset of HGSOC using four different patient cohorts that include pre-chemotherapy, post-neoadjuvant chemotherapy (NACT) and relapsing tumors as well as tumors from various peritoneal locations.

Results

We find that the PODO447 epitope expression is similar across tumor locations and negligibly impacted by chemotherapy. Invariably, tumors with high levels of the PODO447 epitope lack infiltrating CD8+ T cells and CD20+ B cells/plasma cells, an immune phenotype consistently associated with poor outcome.

Discussion

We conclude that the PODO447 glycoepitope is an excellent biomarker of immune "cold" tumors and a candidate for the development of targeted-therapies for these hard-to-treat cancers.

A Cancer-Specific Monoclonal Antibody against Podocalyxin Exerted Antitumor Activities in Pancreatic Cancer Xenografts

Podocalyxin (PODXL) overexpression is associated with poor clinical outcomes in various tumors. PODXL is involved in tumor malignant progression through the promotion of invasiveness and metastasis. Therefore, PODXL is considered a promising target of monoclonal antibody (mAb)-based therapy. However, PODXL also plays an essential role in normal cells, such as vascular and lymphatic endothelial cells. Therefore, cancer specificity or selectivity is required to reduce adverse effects on normal cells. Here, we developed an anti-PODXL cancer-specific mAb (CasMab), PcMab-6 (IgG1, kappa), by immunizing mice with a soluble PODXL ectodomain derived from a glioblastoma LN229 cell. PcMab-6 reacted with the PODXL-positive LN229 cells but not with PODXL-knockout LN229 cells in flow cytometry. Importantly, PcMab-6 recognized pancreatic ductal adenocarcinoma (PDAC) cell lines (MIA PaCa-2, Capan-2, and PK-45H) but did not react with normal lymphatic endothelial cells (LECs). In contrast, one of the non-CasMabs, PcMab-47, showed high reactivity to both the PDAC cell lines and LECs. Next, we engineered PcMab-6 into a mouse IgG2a-type (PcMab-6-mG2a) and a humanized IgG1-type (humPcMab-6) mAb and further produced the core fucose-deficient types (PcMab-6-mG2a-f and humPcMab-6-f, respectively) to potentiate the antibody-dependent cellular cytotoxicity (ADCC). Both PcMab-6-mG2a-f and humPcMab-6-f exerted ADCC and complement-dependent cellular cytotoxicity in the presence of effector cells and complements, respectively. In the PDAC xenograft model, both PcMab-6-mG2a-f and humPcMab-6-f exhibited potent antitumor effects. These results indicated that humPcMab-6-f could apply to antibody-based therapy against PODXL-expressing pancreatic cancers.

Matrix Metalloproteinase 1 as a Marker of Tonsil-Derived Mesenchymal Stem Cells to Assess Bone Marrow Cell Migration

BACKGROUND

To achieve optimal bone marrow engraftment during bone marrow transplantation, migration of donor bone marrow cells (BMCs) toward the recipient's bone marrow is critical. Despite the enhanced engraftment of BMCs by co-administration of mesenchymal stem cells (MSCs), the efficiency can be variable depending on MSC donor. The purpose of this study is to examine the functional heterogeneity of tonsil-derived MSCs (TMSCs) and to identify a marker to evaluate efficacy for the enhancement of BMC migration.

METHODS

To examine the donor-to-donor variation of TMSCs in potentiating BMC migration, we isolated TMSCs from 25 independent donors. Transcriptome of TMSCs and proteome of conditioned medium derived from TMSC were analyzed.

RESULTS

Enhanced BMC migration by conditioned medium derived from TMSCs was variable depending on TMSC donor. The TMSCs derived from 25 donors showed distinct expression profiles compared with other cells, including fibroblasts, adipose-derived MSCs and bone marrow-derived MSCs. TMSCs were distributed in two categories: high- and low-efficacy groups for potentiating BMC migration. Transcriptome analysis of TMSCs and proteome profiles of conditioned medium derived from TMSCs revealed higher expression and secretion of matrix metalloproteinase (MMP) 1 in the high-efficacy group. MMP1 knockdown in TMSCs abrogated the supportive efficacy of conditioned medium derived from TMSC cultures in BMC migration.

CONCLUSION

These data suggest that secreted MMP1 can be used as a marker to evaluate the efficacy of TMSCs in enhancing BMC migration. Furthermore, the strategy of analyzing transcriptomes and proteomes of the MSCs may be useful to set the standard for donor variation.

Targeting a Tumor-Specific Epitope on Podocalyxin Increases Survival in Human Tumor Preclinical Models

Podocalyxin (Podxl) is a CD34-related cell surface sialomucin that is normally highly expressed by adult vascular endothelia and kidney podocytes where it plays a key role in blocking adhesion. Importantly, it is also frequently upregulated on a wide array of human tumors and its expression often correlates with poor prognosis. We previously showed that, in xenograft studies, Podxl plays a key role in metastatic disease by making tumor initiating cells more mobile and invasive. Recently, we developed a novel antibody, PODO447, which shows exquisite specificity for a tumor-restricted glycoform of Podxl but does not react with Podxl expressed by normal adult tissue. Here we utilized an array of glycosylation defective cell lines to further define the PODO447 reactive epitope and reveal it as an O-linked core 1 glycan presented in the context of the Podxl peptide backbone. Further, we show that when coupled to monomethyl auristatin E (MMAE) toxic payload, PODO447 functions as a highly specific and effective antibody drug conjugate (ADC) in killing ovarian, pancreatic, glioblastoma and leukemia cell lines in vitro. Finally, we demonstrate PODO447-ADCs are highly effective in targeting human pancreatic and ovarian tumors in xenografted NSG and Nude mouse models. These data reveal PODO447-ADCs as exquisitely tumor-specific and highly efficacious immunotherapeutic reagents for the targeting of human tumors. Thus, PODO447 exhibits the appropriate characteristics for further development as a targeted clinical immunotherapy.

Prognostic value of nicotinamide N-methyltransferase in human cancers: Evidence from a meta-analysis and database validation

Background

Previous studies indicated that dysregulated expression of nicotinamide N-methyltransferase (NNMT) contributed to the tumor progression and predicted poor prognosis in various cancers. However, there was no exact conclusion on account of the contradictory results across studies.

Methods

The relevant studies up to December 7, 2020 were searched in PubMed, Web of Science, and Embase. The association between NNMT expression and prognostic outcomes was explored, including overall survival (OS), disease-free survival (DFS), and clinicopathological features. The bioinformatics database was used to validate the findings.

Results

Thirteen retrospective studies containing 2,591 patients with cancers were included in this analysis. High NNMT expression was significantly associated with shorter OS (hazard ratio [HR] = 2.01, 95% confidence interval [CI] = 1.42–2.86, and P < 0.01) and DFS (HR = 1.59, 95% CI = 1.23–2.05, and P < 0.01) compared to low NNMT expression in cancers. Compared to patients with low NNMT expression, patients with high NNMT expression tended to have worse tumor differentiation (P = 0.03), earlier lymph node metastasis (P = 0.01), earlier distant metastasis (P = 0.02), and more advanced clinical stage (P < 0.01).

Conclusion

High NNMT expression is an unfavorable factor of various cancers. NNMT is a promising indicator to predict the prognosis of various cancers and can serve as a potential therapeutic target in various cancers.

Prognostic significance of lncRNA DANCR expression in human cancers: a systematic review and meta-analysis

Several studies demonstrated that lncRNA differentiation antagonizing non-protein coding RNA (lncRNA DANCR) expression might have the potential capacity to predict the cancer prognosis; however, definite conclusion has not been obtained. The aim of this meta-analysis was to evaluate the prognostic value of lncRNA DANCR expression in cancers. PubMed, Web of Science, Scopus, and Embase were comprehensively searched for relevant studies. Studies meeting all inclusion standards were included into this meta-analysis. The analysis of overall survival (OS), disease-free survival (DFS), or clinicopathological features was conducted. Total 11 studies containing 1154 cancer patients were analyzed in this meta-analysis. The results showed, compared with low lncRNA DANCR expression, high lncRNA DANCR expression was significantly associated with shorter OS (hazard ratio [HR] = 1.85; 95% CI = 1.52–2.26; P<0.01) and DFS (HR = 1.82; 95% CI = 1.43–2.32; P<0.01) in cancers. Besides, high lncRNA DANCR expression predicted deeper tumor invasion (P<0.01), earlier lymph node metastasis (P<0.01), earlier distant metastasis (P<0.01), and more advanced clinical stage (P<0.01) compared with low lncRNA DANCR expression in cancer populations. High lncRNA DANCR expression was associated with worse prognosis compared with low lncRNA DANCR expression in cancers. LncRNA DANCR expression could serve as a prognostic factor of human cancers.

PODO447: a novel antibody to a tumor-restricted epitope on the cancer antigen podocalyxin

Background

The success of new targeted cancer therapies has been dependent on the identification of tumor-specific antigens. Podocalyxin (Podxl) is upregulated on tumors with high metastatic index and its presence is associated with poor outcome, thus emerging as an important prognostic and theragnostic marker in several human cancers. Moreover, in human tumor xenograft models, Podxl expression promotes tumor growth and metastasis. Although a promising target for immunotherapy, the expression of Podxl on normal vascular endothelia and kidney podocytes could hamper efforts to therapeutically target this molecule. Since pathways regulating post-translational modifications are frequently perturbed in cancer cells, we sought to produce novel anti-Podxl antibodies (Abs) that selectively recognize tumor-restricted glycoepitopes on the extracellular mucin domain of Podxl.

Methods

Splenic B cells were isolated from rabbits immunized with a Podxl-expressing human tumor cell line. Abs from these B cells were screened for potent reactivity to Podxl⁺ neoplastic cell lines but not Podxl⁺ primary endothelial cells. Transcripts encoding heavy and light chain variable regions from promising B cells were cloned and expressed as recombinant proteins. Tumor specificity was assessed using primary normal tissue and an ovarian cancer tissue microarray (TMA). Mapping of the tumor-restricted epitope was performed using enzyme-treated human tumor cell lines and a glycan array.

Results

One mAb (PODO447) showed strong reactivity with a variety of Podxl+ tumor cell lines but not with normal primary human tissue including Podxl+ kidney podocytes and most vascular endothelia. Screening of an ovarian carcinoma TMA (219 cases) revealed PODO447 reactivity with the majority of tumors, including 65% of the high-grade serous histotype. Subsequent biochemical analyses determined that PODO447 reacts with a highly unusual terminal N-acetylgalactosamine beta-1 (GalNAcβ1) motif predominantly found on the Podxl protein core. Finally, Ab–drug conjugates showed specific efficacy in killing tumor cells in vitro.

Conclusions

We have generated a novel and exquisitely tumor-restricted mAb, PODO447, that recognizes a glycoepitope on Podxl expressed at high levels by a variety of tumors including the majority of life-threatening high-grade serous ovarian tumors. Thus, tumor-restricted PODO447 exhibits the appropriate specificity for further development as a targeted immunotherapy.

A cancer-specific anti-podocalyxin monoclonal antibody (60-mG2a-f) exerts antitumor effects in mouse xenograft models of pancreatic carcinoma

Overexpression of podocalyxin (PODXL) is associated with progression, metastasis, and poor outcomes in several cancers. PODXL also plays an important role in the development of normal tissues. For antibody-based therapy to target PODXL-expressing cancers using monoclonal antibodies (mAbs), cancer-specificity is necessary to reduce the risk of adverse effects to normal tissues. In this study, we developed an anti-PODXL cancer-specific mAb (CasMab), named as PcMab-60 (IgM, kappa) by immunizing mice with soluble PODXL, which is overexpressed in LN229 glioblastoma cells. The PcMab-60 reacted with the PODXL-overexpressing LN229 (LN229/PODXL) cells and MIA PaCa-2 pancreatic cancer cells in flow cytometry but did not react with normal vascular endothelial cells (VECs), whereas one of non-CasMabs, PcMab-47 showed high reactivity for not only LN229/PODXL and MIA PaCa-2 cells but also VECs, indicating that PcMab-60 is a CasMab. Next, we engineered PcMab-60 into a mouse IgG_2a-type mAb, named as 60-mG_2a, to add antibody-dependent cellular cytotoxicity (ADCC). We further developed a core fucose-deficient type of 60-mG_2a, named as 60-mG_2a-f, to augment its ADCC activity. In vivo analysis revealed that 60-mG_2a-f exerted antitumor activity in MIA PaCa-2 xenograft models at a dose of 100 μg/mouse/week administered three times. These results suggested that 60-mG_2a-f could be useful for antibody-based therapy against PODXL-expressing pancreatic cancers.

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PODXL is associated with poor outcomes in several cancers.

•

We developed an anti-PODXL cancer-specific mAb (PcMab-60).

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A core fucose-deficient IgG_2a type of PcMab-60 (60-mG_2a-f) exerted antitumor activity in MIA PaCa-2 xenograft models.

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60-mG_2a-f could be useful for antibody-based therapy against PODXL-expressing pancreatic cancers.

Prognostic value of CD44v9 expression in human cancers: A systematic review and meta-analysis

BACKGROUND

The prognostic significance of CD44 variant-9 (CD44v9) expression in human cancers has been investigated in several studies, however, definite conclusion has not be reached. The aim of this systematic review and meta-analysis was to evaluate the prognostic significance of CD44v9 expression in various cancers.

METHODS

Three common databases were searched and retrieved studies were assessed using the inclusion and exclusion criteria. The further analyses for overall survival (OS), recurrence-free survival (RFS), and clinicopathological parameters were performed.

RESULTS

Fifteen studies containing 1633 cancer patients were included into this research. Patients with positive CD44v9 expression tended to have shorter OS (hazard ratio [HR] = 1.93, 95% confidence interval [CI] = 1.48-2.52, P < .01) and RFS (HR = 3.60, 95% CI = 1.52-8.53, P < .01) when compared with patients with negative CD44v9 expression. Positive CD44v9 expression was associated with larger tumor size (P = .04), deeper tumor invasion (P < .01), earlier lymph node metastasis (P < .01), and more advanced clinical stage (P < .01) when compared with negative CD44v9 expression.

CONCLUSION

Positive CD44v9 expression predicted worse prognosis in human cancers compared with negative CD44v9 expression. CD44v9 expression could serve as a prognostic factor of human cancers.

PODXL might be a new prognostic biomarker in various cancers: a meta-analysis and sequential verification with TCGA datasets

ABSRACT

BACKGROUND: Several studies have investigated the associations between the podocalyxin-like protein (PODXL) expression quantity or locations and cancers survival, but the results were far from conclusive. Therefore, we proceeded a meta-analysis on PODXL in various human cancers to find its prognostic value and followed confirmation using the TCGA datasets.

METHODS

We performed a systematic search, and 18 citations, including 5705 patients were pooled in meta-analysis. The results were verified with TCGA datasets.

RESULTS

Total eligible studies comprised 5705 patients with 10 types of cancer. And the result indicated that PODXL high-expression or membrane-expression were significantly related to poor overall survival (OS). However, subgroup analysis showed a significant association between high expressed PODXL and poor OS in the colorectal cancer, pancreatic cancer, urothelial bladder cancer, renal cell carcinoma and glioblastoma multiforme. Then, we validated the inference using TCGA datasets, and the consistent results were demonstrated in patients with pancreatic cancer, glioblastoma multiforme, gastric cancer, esophageal cancer and lung adenocarcinoma.

CONCLUSION

The result of meta-analysis showed that high expressed PODXL was significantly linked with poor OS in pancreatic cancer and glioblastoma multiforme, but not in gastric cancer, esophageal cancer or lung adenocarcinoma. And the membrane expression of PODXL might also associate with poor OS. PODXL may act as tumor promotor and may serve as a potential target for antitumor therapy.

Prognostic significance of red blood cell distribution width in gastrointestinal cancers: A meta-analysis

BACKGROUND

Many publications showed red blood cell distribution width (RDW) might associate with the prognosis of gastrointestinal (GI) cancers, however, the agreement has not been reached because of controversial results. This meta-analysis aimed to explore the prognostic value of RDW in GI cancers.

METHODS

Four common databases were comprehensively searched to look for relevant studies. The meta-analyses for overall survival (OS) and disease-free survival were performed using hazard ratio (HR) and 95% confidence interval (CI), and the meta-analyses for clinical parameters were conducted using odd ratio and 95% CI.

RESULTS

A total of 13 studies involving with 3,509 patients with GI cancers were included into this study. The results showed, compared to patients with low RDW, patients with high RDW tended to have shorter OS (HR = 1.75, 95%CI = 1.57-1.94, P < .01) and disease-free survival (HR = 1.67, 95%CI = 1.39-2.00, P < .01). High RDW was associated with larger tumor size (P < .01), worse differentiation (P = .02), deeper invasion (P < .01), earlier lymph node metastasis (P < .01), more advanced clinical stage (P < .01) and higher carcinoembryonic antigen level (P < .01) when compared to low RDW.

CONCLUSION

High RDW was significantly associated with worse prognosis of GI cancers, which could be regarded as a prognostic biomarker for GI cancers. More prospective studies with large sample size and long follow-up period should be carried out to determine the prognostic significance of RDW in GI cancers in future.

p53's Extended Reach: The Mutant p53 Secretome

p53 suppresses tumorigenesis by activating a plethora of effector pathways. While most of these operate primarily inside of cells to limit proliferation and survival of incipient cancer cells, many extend to the extracellular space. In particular, p53 controls expression and secretion of numerous extracellular factors that are either soluble or contained within extracellular vesicles such as exosomes. As part of the cellular secretome, they execute key roles in cell-cell communication and extracellular matrix remodeling. Mutations in the p53-encoding TP53 gene are the most frequent genetic alterations in cancer cells, and therefore, have profound impact on the composition of the tumor cell secretome. In this review, we discuss how the loss or dominant-negative inhibition of wild-type p53 in concert with a gain of neomorphic properties observed for many mutant p53 proteins, shapes a tumor cell secretome that creates a supportive microenvironment at the primary tumor site and primes niches in distant organs for future metastatic colonization.

Potential oncogenic roles of mutant-p53-derived exosomes in the tumor-host interaction of head and neck cancers

The wide-ranging collection of malignancies arising at the upper aerodigestive tract is categorized as head and neck cancer (HNC), the sixth most prevalent cancer worldwide. Infection with human papillomavirus (HPV) or exposure to carcinogens is the leading causes of HPV+ and HPV- HNCs development, respectively. HPV+ and HPV- HNCs are different in clinical and molecular aspects. Specifically, HPV- HNCs tightly associate with missense mutants of the TP53 gene (encoding for the p53 protein), suggesting a central role for mutant p53 gain-of-function (GOF) in driving tumorigenesis. In contrast, in HPV + HNC, the sequence of TP53 typically remains intact, while the protein is degraded. In tumor cells, the status of the TP53 gene affects the cargo of secreted exosomes. In this review, we describe the accumulated knowledge regarding the involvement of exosomes and p53 on cellular interactions between HPV+ and HPV- HNC cells, and the surrounding tumor microenvironment (TME). Moreover, we envision how TP53 status may determine exosomes cargo in HNC, and, consequently, modify the TME. The potential roles of exosomes described herein are based on both our studies and the studies of others on mutant p53-derived exosomes. Specifically, we showed how exosomes are shed by cancer cells harboring mutant p53 communicate with tumor-associated macrophages in the colon as well as with cancer-associated fibroblasts in the lung, creating immunosuppressive conditions and promoting invasiveness. Altogether, exosomes in HNC in the context of TP53 status are understudied and extensive research is required to shed light on the biology of HPV+ and HPV- HNC.

Keratan Sulphate in the Tumour Environment

Keratan sulphate (KS) is a bioactive glycosaminoglycan (GAG) of some complexity composed of the repeat disaccharide D-galactose β1→4 glycosidically linked to N-acetyl glucosamine. During the biosynthesis of KS, a family of glycosyltransferase and sulphotransferase enzymes act sequentially and in a coordinated fashion to add D-galactose (D-Gal) then N-acetyl glucosamine (GlcNAc) to a GlcNAc acceptor residue at the reducing terminus of a nascent KS chain to effect chain elongation. D-Gal and GlcNAc can both undergo sulphation at C6 but this occurs more frequently on GlcNAc than D-Gal. Sulphation along the developing KS chain is not uniform and contains regions of variable length where no sulphation occurs, regions which are monosulphated mainly on GlcNAc and further regions of high sulphation where both of the repeat disaccharides are sulphated. Each of these respective regions in the KS chain can be of variable length leading to KS complexity in terms of chain length and charge localization along the KS chain. Like other GAGs, it is these variably sulphated regions in KS which define its interactive properties with ligands such as growth factors, morphogens and cytokines and which determine the functional properties of tissues containing KS. Further adding to KS complexity is the identification of three different linkage structures in KS to asparagine (N-linked) or to threonine or serine residues (O-linked) in proteoglycan core proteins which has allowed the categorization of KS into three types, namely KS-I (corneal KS, N-linked), KS-II (skeletal KS, O-linked) or KS-III (brain KS, O-linked). KS-I to -III are also subject to variable addition of L-fucose and sialic acid groups. Furthermore, the GlcNAc residues of some members of the mucin-like glycoprotein family can also act as acceptor molecules for the addition of D-Gal and GlcNAc residues which can also be sulphated leading to small low sulphation glycoforms of KS. These differ from the more heavily sulphated KS chains found on proteoglycans. Like other GAGs, KS has evolved molecular recognition and information transfer properties over hundreds of millions of years of vertebrate and invertebrate evolution which equips them with cell mediatory properties in normal cellular processes and in aberrant pathological situations such as in tumourogenesis. Two KS-proteoglycans in particular, podocalyxin and lumican, are cell membrane, intracellular or stromal tissue-associated components with roles in the promotion or regulation of tumour development, mucin-like KS glycoproteins may also contribute to tumourogenesis. A greater understanding of the biology of KS may allow better methodology to be developed to more effectively combat tumourogenic processes.

Role of lncRNA-ATB in ovarian cancer and its mechanisms of action

This study aimed to elucidate the role of long non-coding RNA activated by transforming growth factor-β (lncRNA-ATB) in ovarian cancer and its underlying mechanisms of action. Expression levels of lncRNA-ATB in ovarian cancer cell line SKOV3 and in a healthy human ovarian cell line were compared using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results indicated that lncRNA-ATB was expressed at significantly higher levels in SKOV3 cells compared with the healthy cell line. After downregulation of lncRNA-ATB expression in SKOV3 cells using lncRNA-ATB-short hairpin RNA, cell proliferation, apoptosis, invasion and migration were assessed using Cell counting kit-8, Live Dead staining, Transwell assay and wound healing assay, respectively. RT-qPCR and western blotting were used to quantify the expression of signal transducer and activator of transcription 3 (STAT3), phosphorylated (p)-STAT3, and the additional epithelial to mesenchymal transition (EMT)-related proteins E-cadherin and vimentin in SKOV3 cells. LncRNA-ATB downregulation significantly reduced SKOV3 cell proliferation, invasion and migration, promoted apoptosis, decreased the expression of p-STAT3 and vimentin, and increased E-cadherin expression. Taken together, these results suggest that lncRNA-ATB downregulation can inhibit ovarian cancer cell proliferation, invasion and migration, and promote cell apoptosis. Lnc-RNA-ATB may therefore be a new target for ovarian cancer treatment.

Array expression meta-analysis of cancer stem cell genes identifies upregulation of PODXL especially in DCC low expression meningiomas

BACKGROUND

Meningiomas are the most common intracranial tumors, with a subset of cases bearing a progressive phenotype. The DCC netrin 1 receptor (DCC) is a candidate gene for early meningioma progression. Cancer stem cell (CSC) genes are emerging as cancer therapeutic targets, as their expression is frequently associated with aggressive tumor phenotypes. The main objective of the study was to identify deregulated CSC genes in meningiomas.

MATERIALS AND METHODS

Interrogating two expression data repositories, significantly differentially expressed genes (DEGs) were determined using DCC low vs. DCC high expression groups and WHO grade I (GI) vs. grade II + grade III (GII + GIII) comparison groups. Human stem cell (SC) genes were compiled from two published data sets and were extracted from the DEG lists. Biofunctional analysis was performed to assess associations between genes or molecules.

RESULTS

In the DCC low vs. DCC high expression groups, we assessed seven studies representing each between seven and 58 samples. The type I transmembrane protein podocalyxin like (PODXL) was markedly upregulated in DCC low expression meningiomas in six studies. Other CSC genes repeatedly deregulated included, e.g., BMP/retinoic acid inducible neural specific 1 (BRINP1), prominin 1 (PROM1), solute carrier family 24 member 3 (SLC24A3), rRho GTPase activating protein 28 (ARHGAP28), Kruppel like factor 5 (KLF5), and leucine rich repeat containing G protein-coupled receptor 4 (LGR4). In the GI vs. GII + GIII comparison groups, we assessed six studies representing each between nine and 68 samples. DNA topoisomerase 2-alpha (TOP2A) was markedly upregulated in GII + GIII meningiomas in four studies. Other CSC genes repeatedly deregulated included, e.g., ARHGAP28 and PODXL. Network analysis revealed associations of molecules with, e.g., cellular development and movement; nervous system development and function; and cancer.

CONCLUSIONS

This meta-analysis on meningiomas identified a comprehensive list of deregulated CSC genes across different array expression studies. Especially, PODXL is of interest for functional assessment in progressive meningiomas.

Keratan sulfate (KS)-proteoglycans and neuronal regulation in health and disease: the importance of KS-glycodynamics and interactive capability with neuroregulatory ligands

Compared to the other classes of glycosaminoglycans (GAGs), that is, chondroitin/dermatan sulfate, heparin/heparan sulfate and hyaluronan, keratan sulfate (KS), have the least known of its interactive properties. In the human body, the cornea and the brain are the two most abundant tissue sources of KS. Embryonic KS is synthesized as a linear poly-N-acetyllactosamine chain of d-galactose-GlcNAc repeat disaccharides which become progressively sulfated with development, sulfation of GlcNAc is more predominant than galactose. KS contains multi-sulfated high-charge density, monosulfated and non-sulfated poly-N-acetyllactosamine regions and thus is a heterogeneous molecule in terms of chain length and charge distribution. A recent proteomics study on corneal KS demonstrated its interactivity with members of the Slit-Robbo and Ephrin-Ephrin receptor families and proteins which regulate Rho GTPase signaling and actin polymerization/depolymerization in neural development and differentiation. KS decorates a number of peripheral nervous system/CNS proteoglycan (PG) core proteins. The astrocyte KS-PG abakan defines functional margins of the brain and is up-regulated following trauma. The chondroitin sulfate/KS PG aggrecan forms perineuronal nets which are dynamic neuroprotective structures with anti-oxidant properties and roles in neural differentiation, development and synaptic plasticity. Brain phosphacan a chondroitin sulfate, KS, HNK-1 PG have roles in neural development and repair. The intracellular microtubule and synaptic vesicle KS-PGs MAP1B and SV2 have roles in metabolite transport, storage, and export of neurotransmitters and cytoskeletal assembly. MAP1B has binding sites for tubulin and actin through which it promotes cytoskeletal development in growth cones and is highly expressed during neurite extension. The interactive capability of KS with neuroregulatory ligands indicate varied roles for KS-PGs in development and regenerative neural processes.

Podocalyxin-like protein promotes gastric cancer progression through interacting with RUN and FYVE domain containing 1 protein

Podocalyxin‐like protein (PODXL), a transmembrane glycoprotein with anti‐adhesive properties, is associated with an aggressive tumor phenotype and poor prognosis of several cancers. To elucidate the biological significance of PODXL and its molecular mechanism in gastric cancer (GC), we investigated the expression of PODXL in GC samples and assessed its effects on biological behaviors and the related signaling pathways in vitro and in vivo. Moreover, the possible and closely interacted partners of PODXL were identified. Our data showed that the protein or mRNA level of PODXL was significantly upregulated in tissues or serum of GC patients compared with normal‐appearing tissues (NAT) or those of healthy volunteers. Overall survival (OS) curves showed that patients with high PODXL levels in tissues or serum had a worse 5‐year OS. In vitro, restoring PODXL expression promoted tumor progression by increasing cell proliferation, colony formation, wound healing, migration and invasion, as well as suppressing the apoptosis. Furthermore, the PI3K/AKT, NF‐κB and MAPK/ERK signaling pathways were activated. There was a significant positive correlation between PODXL and RUN and FYVE domain containing 1 (RUFY1) expression in tissues or serum. Subsequent mass spectrometry analysis, co‐immunoprecipitation assays and western blot analysis identified PODXL/RUFY1 complexes in GC cells, and silencing RUFY1 expression in GC cells significantly attenuated PODXL‐induced phenotypes and their underlying signaling pathways. Our results suggested that PODXL promoted GC progression via a RUFY1‐dependent signaling mechanism. New GC therapeutic opportunities through PODXL and targeting the PODXL/RUFY1 complex might improve cancer therapy.

Mutant p53s generate pro-invasive niches by influencing exosome podocalyxin levels

Mutant p53s (mutp53) increase cancer invasiveness by upregulating Rab-coupling protein (RCP) and diacylglycerol kinase-α (DGKα)-dependent endosomal recycling. Here we report that mutp53-expressing tumour cells produce exosomes that mediate intercellular transfer of mutp53's invasive/migratory gain-of-function by increasing RCP-dependent integrin recycling in other tumour cells. This process depends on mutp53's ability to control production of the sialomucin, podocalyxin, and activity of the Rab35 GTPase which interacts with podocalyxin to influence its sorting to exosomes. Exosomes from mutp53-expressing tumour cells also influence integrin trafficking in normal fibroblasts to promote deposition of a highly pro-invasive extracellular matrix (ECM), and quantitative second harmonic generation microscopy indicates that this ECM displays a characteristic orthogonal morphology. The lung ECM of mice possessing mutp53-driven pancreatic adenocarcinomas also displays increased orthogonal characteristics which precedes metastasis, indicating that mutp53 can influence the microenvironment in distant organs in a way that can support invasive growth.

Overexpression of the Pluripotent Stem Cell Marker Podocalyxin in Prostate Cancer

BACKGROUND/AIM

Podocalyxin, a member of the CD34 family of cell surface sialomucins, is overexpressed in human embryonal carcinoma cell lines, as well as in several cancer types, and is associated with poor prognosis. Podocalyxin variants are associated with an increased risk and aggressiveness of prostate cancer. Herein podocalyxin protein expression in prostate cancer was characterized.

MATERIALS AND METHODS

Expression of podocalyxin as well as of TRA-1-60 and TRA-1-81 antigens was assessed immunohistochemically in 84 radical prostatectomy specimens and in adjacent normal tissues.

RESULTS

Podocalyxin expression and H-scores were considerably higher in prostate tumors compared to normal tissues. High TRA-1-60 and TRA-1-81 staining was detected, however, in a much smaller percentage of prostate tumors, while their expression and H-scores were low in normal tissues. Similar trends for all three proteins were observed in prostatic intraepithelial neoplasia.

CONCLUSION

Overexpression of podocalyxin in prostate cancer renders the protein a putative immunohistochemical marker of prostate cancer that may contribute to stratification of patients for optimal treatment.

Long non-coding RNA activated by TGF-β expression in cancer prognosis: A meta-analysis

BACKGROUND

Recently, long non-coding RNA activated by transforming growth factor beta (TGF-β) (lncRNA ATB) was shown to be useful in cancer prognosis, however, its prognostic value in human cancer has been inconsistent. Our study aimed to explore the prognostic role of lncRNA ATB expression in cancer prognosis.

METHODS

PubMed, Embase, and Cochrane Library databases were thoroughly searched to retrieve studies focusing on the prognostic role of lncRNA ATB expression in cancer, and meta-analysis was performed.

RESULTS

A total of 15 studies were included into this meta-analysis. High lncRNA ATB expression was significantly related to shorter overall survival (OS) (HR = 2.44, 95%CI = 1.98-3.01, P < 0.01), recurrence-free survival (RFS) (HR = 1.85, 95%CI = 1.42-2.40, P < 0.01), disease-free survival (DFS) (HR = 3.61, 95%CI = 2.45-5.33, P < 0.01), and progression-free survival (PFS) (HR = 2.97, 95%CI = 2.12-4.16, P < 0.01) when compared with low lncRNA ATB expression in cancer. Moreover, Patients with high lncRNA ATB expression tended to have worse tumor differentiation (P < 0.01), more advanced clinical stage (P < 0.01), deeper tumor invasion (P < 0.01), earlier distant metastases (P = 0.02), lymph node metastases (P = 0.04), and vascular invasion (P < 0.01) when compared with those with low lncRNA ATB expression.

CONCLUSIONS

High lncRNA ATB expression was significantly associated with worse prognosis in cancer. LncRNA ATB expression could be used as a prognostic biomarker for human cancer.

Anti-podocalyxin antibody exerts antitumor effects via antibody-dependent cellular cytotoxicity in mouse xenograft models of oral squamous cell carcinoma

Podocalyxin (PODXL) overexpression is associated with progression, metastasis, and poor outcomes in cancers. We recently produced the novel anti-PODXL monoclonal antibody (mAb) PcMab-47 (IgG₁, kappa). Herein, we engineered PcMab-47 into 47-mG_2a, a mouse IgG_2a-type mAb, to add antibody-dependent cellular cytotoxicity (ADCC). We further developed 47-mG_2a-f, a core fucose-deficient type of 47-mG_2a to augment its ADCC. Immunohistochemical analysis of oral cancer tissues using PcMab-47 and 47-mG_2a revealed that the latter stained oral squamous cell carcinoma (OSCC) cells in a cytoplasmic pattern at a much lower concentration. PcMab-47 and 47-mG_2a detected PODXL in 163/201 (81.1%) and in 197/201 (98.0%) OSCC samples, respectively. 47-mG_2a-f also detected PODXL in OSCCs at a similar frequency as 47-mG_2a. In vitro analysis revealed that both 47-mG_2a and 47-mG_2a-f exhibited strong complement-dependent cytotoxicity (CDC) against CHO/hPODXL cells. In contrast, 47-mG_2a-f exhibited much stronger ADCC than 47-mG_2a against OSCC cells, indicating that ADCC and CDC of those anti-PODXL mAbs depend on target cells. In vivo analysis revealed that both 47-mG_2a and 47-mG_2a-f exerted antitumor activity in CHO/hPODXL xenograft models at a dose of 100 μg or 500 μg/mouse/week administered twice. 47-mG_2a-f, but not 47-mG_2a, exerted antitumor activity in SAS and HSC-2 xenograft models at a dose of 100 μg/mouse/week administered three times. Although both 47-mG_2a and 47-mG_2a-f exerted antitumor activity in HSC-2 xenograft models at a dose of 500 μg/mouse/week administered twice, 47-mG_2a-f also showed higher antitumor activity than 47-mG_2a. These results suggested that a core fucose-deficient anti-PODXL mAb could be useful for antibody-based therapy against PODXL-expressing OSCCs.

Prognostic and clinicopathological value of SIRT3 expression in various cancers: a systematic review and meta-analysis

Background

Several studies have explored the prognostic value of sirtuin 3 (SIRT3) in various cancers, but obtained inconsistent results. The current systematic review and meta-analysis was conducted to investigate the association between SIRT3 expression and prognosis in various cancers.

Methods

PubMed, Embase, Web of Science and the Cochrane Library were comprehensively retrieved by the end of September 29, 2017. All the relevant studies were checked and included in the meta-analysis if they met the inclusion criteria.

Results

A total of 17 studies involving 2,865 patients were included in the systematic review and meta-analysis. The results indicated that SIRT3 expression was not significantly associated with overall survival (OS) (hazard ratio [HR]=0.87, 95% CI=0.59–1.29, P=0.50) and disease-free survival (HR=0.87, 95% CI=0.57–1.31, P=0.50) in total various cancers. However, significant relationship between SIRT3 expression and OS in specific cancers was detected, including chronic lymphocytic leukemia (CLL) (HR=0.48, 95% CI=0.26–0.89, P=0.019), hepatocellular carcinoma (HCC) (HR=0.56, 95% CI=0.42–0.74, P<0.001), pancreatic carcinoma (PC) (HR=0.55, 95% CI=0.30–1.00, P=0.049), renal cell carcinoma (RCC) (HR=0.13, 95% CI=0.02–0.98, P=0.048), breast cancer (BC) (HR=2.53, 95% CI=1.83–3.67, P<0.001), colon cancer (CC) (HR=1.87, 95% CI=1.12–3.26, P=0.022) and non-small-cell lung cancer (NSCLC) (HR=2.20, 95% CI=1.38–3.50, P=0.001). Moreover, SIRT3 expression was obviously associated with tumor size (odds ratio [OR]=1.41, 95% CI=1.02–1.94, P=0.04), tumor differentiation (OR=1.52, 95% CI=1.08–2.16, P=0.02) and clinical stage (OR=2.07, 95% CI=1.23–3.46, P=0.01) in HCC.

Conclusion

SIRT3 was distinctly related to the OS in specific cancers. SIRT3 was an unfavorable prognostic factor in BC, CC and NSCLC; however, it was also a favorable prognostic factor in CLL, HCC, PC and RCC, especially in HCC.

Prognostic value of platelet-to-lymphocyte ratio in pancreatic cancer: a comprehensive meta-analysis of 17 cohort studies

Background and aims

Several studies were conducted to explore the prognostic value of platelet-to-lymphocyte ratio (PLR) in pancreatic cancer and have reported contradictory results. This study aims to summarize the prognostic role of PLR in pancreatic cancer.

Materials and methods

Embase, PubMed and Cochrane Library were completely searched. The cohort studies focusing on the prognostic role of PLR in pancreatic cancer were eligible. The overall survival (OS) and progression-free survival (PFS) were analyzed.

Results

Fifteen papers containing 17 cohort studies with pancreatic cancer were identified. The results showed patients that with low PLR might have longer OS when compared to the patients with high PLR (hazard ratio=1.28, 95% CI=1.17–1.40, P<0.00001; I²=42%). Similar results were observed in the subgroup analyses of OS, which was based on the analysis model, ethnicity, sample size and cut-off value. Further analyses based on the adjusted potential confounders were conducted, including CA199, neutrophil-to-lymphocyte ratio, modified Glasgow Prognostic Score, albumin, C-reactive protein, Eastern Cooperative Oncology Group, stage, tumor size, nodal involvement, tumor differentiation, margin status, age and gender, which confirmed that low PLR was a protective factor in pancreatic cancer. In addition, low PLR was significantly associated with longer PFS when compared to high PLR in pancreatic cancer (hazard ratio=1.27, 95% CI=1.03–1.57, P=0.03; I²=33%).

Conclusion

In conclusion, it was found that high PLR is an unfavorable predictor of OS and PFS in patients with pancreatic cancer, and PLR is a promising prognostic biomarker for pancreatic cancer.

Keratan sulfate, a complex glycosaminoglycan with unique functional capability

From an evolutionary perspective keratan sulfate (KS) is the newest glycosaminoglycan (GAG) but the least understood. KS is a sophisticated molecule with a diverse structure, and unique functional roles continue to be uncovered for this GAG. The cornea is the richest tissue source of KS in the human body but the central and peripheral nervous systems also contain significant levels of KS and a diverse range of KS-proteoglycans with essential functional roles. KS also displays important cell regulatory properties in epithelial and mesenchymal tissues and in bone and in tumor development of diagnostic and prognostic utility. Corneal KS-I displays variable degrees of sulfation along the KS chain ranging from non-sulfated polylactosamine, mono-sulfated and disulfated disaccharide regions. Skeletal KS-II is almost completely sulfated consisting of disulfated disaccharides interrupted by occasional mono-sulfated N-acetyllactosamine residues. KS-III also contains highly sulfated KS disaccharides but differs from KS-I and KS-II through 2-O-mannose linkage to serine or threonine core protein residues on proteoglycans such as phosphacan and abakan in brain tissue. Historically, the major emphasis on the biology of KS has focused on its sulfated regions for good reason. The sulfation motifs on KS convey important molecular recognition information and direct cell behavior through a number of interactive proteins. Emerging evidence also suggest functional roles for the poly-N-acetyllactosamine regions of KS requiring further investigation. Thus further research is warranted to better understand the complexities of KS.

Serum podocalyxin levels correlate with carotid intima media thickness, implicating its role as a novel biomarker for atherosclerosis

Podocalyxin is a cell surface sialomucin, which is expressed in not only glomerular podocytes but also vascular endothelial cells. Urinary podocalyxin is used as a marker for glomerular disease. However, there are no reports describing serum podocalyxin (s-Podxl) levels. Therefore, the association between s-Podxl levels and clinical parameters were examined with 52 patients. s-Podxl level was evaluated using enzyme-linked immunosorbent assay. The median s-Podxl level was 14.2 ng/dL (interquartile range: 10.8–22.2 ng/dL). There were significant correlations (correlation coefficient: r > 0.2) of s-Podxl levels with carotid intima media thickness (IMT) (r = 0.30, p = 0.0307). Multiple logistic regression analysis showed that s-Podxl levels remained significantly associated with carotid IMT > 1 mm (OR: 1.15; 95% CI 1.02–1.31, p = 0.026) after adjustments for traditional cardiovascular risk factors such as age, sex, current smoking status, hypertension, dyslipidemias, and diabetes. In conclusion, s-Podxl is independently associated with carotid IMT and might be used as a novel biomarker for cardiovascular disease.

Prognostic role of platelet to lymphocyte ratio in hepatocellular carcinoma: a systematic review and meta-analysis

BACKGROUND AND AIMS

Several studies were conducted to explore the prognostic significance of platelet to lymphocyte ratio (PLR) in hepatocellular carcinoma (HCC), however, contradictory results across most reports were documented. To this end, we present a systematic review that aims to summarize the prognostic significance of PLR in patients with HCC.

RESULTS

A total of 10 studies involving a total of 2,315 patients were identified. The Newcastle-Ottawa Quality Assessment Scale (NOS) of each included study was greater than or equal to 5. The results indicated that high PLR was significantly associated with a worse OS when compared to the low PLR (HR = 1.60, 95% CI = 1.23-2.08, p = 0.0005; I2 = 88%, p < 0.00001). Similar results were detected in the subgroup analysis of the analysis model, cut-off value, ethnicity, sample size and therapy. However, no obvious correlation between the PLR and DFS/RFS in patients with HCC was observed (HR = 1.21, 95% CI = 0.87-1.67, p = 0.26; I2 = 61%, p = 0.07).

MATERIALS AND METHODS

A complete literature search in the PubMed, Cochrane Library and Embase database was performed. Retrospective and prospective studies focusing on the role of PLR on the prognosis in HCC were all deemed as "suitable" for our scope. The endpoints determined were: the overall survival (OS), disease-free survival (DFS), recurrence-free survival (RFS) and the progress free survival (PFS).

CONCLUSIONS

The study revealed that high PLR is an unfavorable predictor of OS in patients with HCC, and high PLR is a promising prognostic biomarker for HCC, especially for patients in Asia.

Prognostic role of long non-coding RNA TUG1 expression in various cancers: a meta-analysis

Several studies were conducted to explore the prognostic role of long non-coding RNA taurine upregulated gene 1 (lncRNA TUG1) expression in various cancers, with contradictory. This study aims to summarize the prognostic role of lncRNA TUG1 expression in various cancers. Embase, PubMed and Cochrane Library were completely retrieved. The cohort studies focusing on the prognostic role of lncRNA TUG1 expression in various cancers were eligible. The endpoints were overall survival (OS) and clinicopathological parameters. 9 studies involving a total of 1,078 patients were identified. The results showed that high lncRNA TUG1 expression was obviously associated with worse OS when compared to the low lncRNA TUG1 expression (HR = 1.37, 95% CI = 1.07–1.76, P = 0.01; I² = 85%). However, No distinct relationship was observed between the lncRNA TUG1 expression and age (OR = 0.99, 95% CI = 0.76–1.28, P = 0.92; I2 = 4%), gender (OR = 0.92, 95% CI = 0.70–1.22, P = 0.57; I² = 0%), diameter (OR = 0.83, 95% CI = 0.34–2.01, P = 0.67; I² = 85%), smoking (OR = 1.09, 95% CI = 0.37–3.21, P = 0.87; I² = 73%), TNM stage (OR = 0.60, 95% CI = 0.25–1.43, P = 0.25; I² = 86%) and lymph node metastasis (OR = 1.07, 95% CI = 0.47–2.45, P = 0.87; I² = 86%). In conclusion, it was revealed that high lncRNA TUG1 expression is an unfavorable predictor of OS in patients with cancers, and lncRNA TUG1 expression is a promising prognostic biomarker for various cancers.