Inhibition of TGFBIp expression reduces lymphangiogenesis and tumor metastasis

Prognostic biomarkers associated with immune checkpoint inhibitors in hepatocellular carcinoma

The treatment of hepatocellular carcinoma (HCC), particularly advanced HCC, has been a serious challenge. Immune checkpoint inhibitors (ICIs) are landmark drugs in the field of cancer therapy in recent years, which have changed the landscape of cancer treatment. In the field of HCC treatment, this class of drugs has shown good therapeutic prospects. For example, atezolizumab in combination with bevacizumab has been approved as first-line treatment for advanced HCC due to significant efficacy. However, sensitivity to ICI therapy varies widely among HCC patients. Therefore, there is an urgent need to search for determinants of resistance/sensitivity to ICIs and to screen biomarkers that can predict the efficacy of ICIs. This manuscript reviews the research progress of prognostic biomarkers associated with ICIs in HCC in order to provide a scientific basis for the development of clinically individualised precision medication regimens.

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.

Exosomal and intracellular miR-320b promotes lymphatic metastasis in esophageal squamous cell carcinoma

Cancer-cell-released exosomal microRNAs (miRNAs) are important mediators of cell-cell communication in the tumor microenvironment. In this study, we sequenced serum exosome miRNAs from esophageal squamous cell carcinoma (ESCC) patients and identified high expression of miR-320b to be closely associated with peritumoral lymphangiogenesis and lymph node (LN) metastasis. Functionally, miR-320b could be enriched and transferred by ESCC-released exosomes directly to human lymphatic endothelial cells (HLECs), promoting tube formation and migration in vitro and facilitating lymphangiogenesis and LN metastasis in vivo as assessed by gain- and loss-of-function experiments. Furthermore, we found programmed cell death 4 (PDCD4) as a direct target of miR-320b through bioinformatic prediction and luciferase reporter assay. Re-expression of PDCD4 could rescue the effects induced by exosomal miR-320b. Notably, the miR-320b-PDCD4 axis activates the AKT pathway in HLECs independent of vascular endothelial growth factor-C (VEGF-C). Moreover, overexpression of miR-320b promotes the proliferation, migration, invasion, and epithelial-mesenchymal transition progression of ESCC cells. Finally, we demonstrate that METTL3 could interact with DGCR8 protein and positively modulate pri-miR-320b maturation process in an N6-methyladenosine (m6A)-dependent manner. Therefore, our findings uncover a VEGF-C-independent mechanism of exosomal and intracellular miR-320b-mediated LN metastasis and identify miR-320b as a novel predictive marker and therapeutic target for LN metastasis in ESCC.

The role of the extracellular matrix protein TGFBI in cancer

The secreted extracellular protein, transforming growth factor beta induced (TGFBI or βIGH3), has roles in regulating numerous biological functions, including cell adhesion and bone formation, both during embryonic development and during the pathogenesis of human disease. TGFBI has been most studied in the context of hereditary corneal dystrophies, where mutations in TGFBI result in accumulation of TGFBI in the cornea. In cancer, early studies focused on TGFBI as a tumor suppressor, in part by promoting chemotherapy sensitivity. However, in established tumors, TGFBI largely has a role in promoting tumor progression, with elevated levels correlating to poorer clinical outcomes. As an important regulator of cancer progression, TGFBI expression and function is tightly regulated by numerous mechanisms including epigenetic silencing through promoter methylation and microRNAs. Mechanisms to target TGFBI have potential clinical utility in treating advanced cancers, while assessing TGFBI levels could be a biomarker for chemotherapy resistance and tumor progression.

Lysosomal dysfunction of corneal fibroblasts underlies the pathogenesis of Granular Corneal Dystrophy Type 2 and can be rescued by TFEB

Granular corneal dystrophy type 2 (GCD2) is the most common form of transforming growth factor β‐induced (TGFBI) gene‐linked corneal dystrophy and is pathologically characterized by the corneal deposition of mutant‐TGFBIp. The defective autophagic degradation of pathogenic mutant‐TGFBIp has been shown in GCD2; however, its exact mechanisms are unknown. To address this, we investigated lysosomal functions using corneal fibroblasts. Levels of cathepsins K and L (CTSK and CTSL) were significantly decreased in GCD2 cells, but of cathepsins B and D (CTSB and CTSD) did not change. The maturation of the pro‐enzymes to their active forms (CTSB, CTSK and CTSL) was inhibited in GCD2 cells. CTSL enzymes directly degraded both LC3 (autophagosomes marker) and mutant‐TGFBIp. Exogenous CTSL expression dramatically reduced mutant‐TGFBIp in GCD2 cells, but not TGFBIp in WT cells. An increased lysosomal pH and clustered lysosomal perinuclear position were found in GCD2 cells. Transcription factor EB (TFEB) levels were significantly reduced in GCD2 cells, compared to WT. Notably, exogenous TFEB expression improved mutant‐TGFBIp clearance and lysosomal abnormalities in GCD2 cells. Taken together, lysosomal dysfunction in the corneal fibroblasts underlies the pathogenesis of GCD2, and TFEB has a therapeutic potential in the treatment of GCD2.

TGFBIp mediates lymphatic sprouting in corneal lymphangiogenesis

Corneal lymphangiogenesis plays a key role in diverse pathological conditions of the eye. Here, we demonstrate that a versatile extracellular matrix protein, transforming growth factor-β induced protein (TGFBIp), promotes lymphatic sprouting in corneal lymphangiogenesis. TGFBIp is highly up-regulated in inflamed mouse corneas. Immunolocalization of TGFBIp is detected in infiltrating macrophages in inflamed mouse corneas. Subconjunctival injection of liposomal clodronate can significantly reduce macrophage infiltration in inflamed mouse cornea, and decrease the expression of TGFBIp and areas of corneal lymphangiogenesis and angiogenesis after corneal suture placement. In brief, these results indicate that the up-regulation of TGFBIp in sutured cornea correlates with macrophage infiltration. Although TGFBIp alone cannot significantly stimulate corneal lymph vessel ingrowth in vivo, it can enhance the effect of vascular endothelial growth factor-C in promoting corneal lymphangiogenesis. The in vitro results show that TGFBIp promotes migration, tube formation and adhesion of human lymphatic endothelial cells (HLECs), but it has no effect on HLECs' proliferation. We also find that the in vitro effect of TGFBIp is mediated by the integrin α5β1-FAK pathway. Additionally, integrin α5β1 blockade can significantly inhibit lymphatic sprouting induced by TGFBIp. Taken together, these findings reveal a new molecular mechanism of lymphangiogenesis in which the TGFBIp-integrin pathways plays a pivotal role in lymphatic sprouting.

Generation of TGFBI knockout ABCG2+/ABCB5+ double-positive limbal epithelial stem cells by CRISPR/Cas9-mediated genome editing

Corneal dystrophy is an autosomal dominant disorder caused by mutations of the transforming growth factor β-induced (TGFBI) gene on chromosome 5q31.8. This disease is therefore ideally suited for gene therapy using genome-editing technology. Here, we isolated human limbal epithelial stem cells (ABCG2+/ABCB5+ double-positive LESCs) and established a TGFBI knockout using RNA-guided clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 genome editing. An LESC clone generated with a single-guide RNA (sgRNA) targeting exon 4 of the TGFBI gene was sequenced in order to identify potential genomic insertions and deletions near the Cas9/sgRNA-target sites. A detailed analysis of the differences between wild type LESCs and the single LESC clone modified by the TGFBI-targeting sgRNA revealed two distinct mutations, an 8 bp deletion and a 14 bp deletion flanked by a single point mutation. These mutations each lead to a frameshift missense mutation and generate premature stop codons downstream in exon 4. To validate the TGFBI knockout LESC clone, we used single cell culture to isolate four individual sub-clones, each of which was found to possess both mutations present in the parent clone, indicating that the population is homogenous. Furthermore, we confirmed that TGFBI protein expression is abolished in the TGFBI knockout LESC clone using western blot analysis. Collectively, our results suggest that genome editing of TGFBI in LESCs by CRISPR/Cas9 may be useful strategy to treat corneal dystrophy.

B cell and B cell-related pathways for novel cancer treatments

B cells are recognized as the main effector cells of humoral immunity which suppress tumor progression by secreting immunoglobulins, promoting T cell response, and killing cancer cells directly. Given these properties, their anti-tumor immune response in the tumor micro-environment (TME) is of great interest. Although T cell-related immune responses have become a therapeutic target with the introduction of immune checkpoint inhibitors, not all patients benefit from these treatments. B cell and B cell-related pathways (CCL19, -21/CCR7 axis and CXCL13/CXCR5 axis) play key roles in activating immune response through humoral immunity and local immune activation via tertiary lymphoid structure (TLS) formation. However they have some protumorigenic works in the TME. Thus, a better understanding of B cell and B cell-related pathways is necessary to develop effective cancer control. In this review, we summarize recent evidences regarding the roles of B cell and B cell-related pathways in the TME and immune response and discuss their potential roles for novel cancer treatment strategies.

Cervical squamous cell carcinoma-secreted exosomal miR-221-3p promotes lymphangiogenesis and lymphatic metastasis by targeting VASH1

Cancer-secreted exosomal miRNAs are emerging mediators of cancer-stromal cross-talk in the tumor environment. Our previous miRNAs array of cervical squamous cell carcinoma (CSCC) clinical specimens identified upregulation of miR-221-3p. Here, we show that miR-221-3p is closely correlated with peritumoral lymphangiogenesis and lymph node (LN) metastasis in CSCC. More importantly, miR-221-3p is characteristically enriched in and transferred by CSCC-secreted exosomes into human lymphatic endothelial cells (HLECs) to promote HLECs migration and tube formation in vitro, and facilitate lymphangiogenesis and LN metastasis in vivo according to both gain-of-function and loss-of-function experiments. Furthermore, we identify vasohibin-1 (VASH1) as a novel direct target of miR-221-3p through bioinformatic target prediction and luciferase reporter assay. Re-expression and knockdown of VASH1 could respectively rescue and simulate the effects induced by exosomal miR-221-3p. Importantly, the miR-221-3p-VASH1 axis activates the ERK/AKT pathway in HLECs independent of VEGF-C. Finally, circulating exosomal miR-221-3p levels also have biological function in promoting HLECs sprouting in vitro and are closely associated with tumor miR-221-3p expression, lymphatic VASH1 expression, lymphangiogenesis, and LN metastasis in CSCC patients. In conclusion, CSCC-secreted exosomal miR-221-3p transfers into HLECs to promote lymphangiogenesis and lymphatic metastasis via downregulation of VASH1 and may represent a novel diagnostic biomarker and therapeutic target for metastatic CSCC patients in early stages.

Bone Marrow Derived Mesenchymal Stem Cells Involve in the Lymphangiogenesis of Lung Cancer and Jinfukang Inhibits the Involvement In Vivo

Lymphangiogenesis plays an important role in cancer metastasis. Bone marrow-derived mesenchymal stem cells (BMMSCs) migrate to the site of tumorigenesis and in turn promote the metastasis. However, whether BMMSCs involve in the lymphangiogenesis of lung cancer is unclear. Jinfukang has clinically been used for the treatment of non small cell lung cancer (NSCLC) in China. In this study, to investigate the involvement of BMMSCs in lymphangiogenesis in lung cancer, and evaluate the inhibitory effect of Jinfukang on the lymphangiogenesis, chimeric mice were prepared by transplanting bone marrow from green fluorescent protein (GFP) transgenic mice (C57BL/6-EGFP) into irradiated C57BL/6 mice. Then, the chimeric mice were injected subcutaneously with freshly prepared Lewis lung carcinoma cell suspension to make lung tumor model, and the model mice were further orally administrated with Jinfukang once per day for 3 weeks. Four weeks after the bone marrow transplantation, GFP-positive cells primarily existed in bone marrow of acceptor mice, and three more weeks after, Lewis lung carcinoma cells formed a tumor mass in chimeric mice. Observation of GFP-positive cells revealed that BMMSCs transferred into the lung tumor. Immunofluorescent analyses of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), a lymphatic endothelium marker, demonstrated a part of lymphatic endothelial cells in lung cancer were derived from BMMSCs, and those lymphatic endothelial cells contributed to the lung tumor lymphangiogenesis. Furthermore, Jinfukang treatment resulted in a significant reduction of the average weight of the tumor mass in chimeric mice, and displayed a significant lower number of LYVE-1 positive cells. The present results suggest that BMMSCs transfer to tumor, differentiate into lymphatic endothelial cells, and involve in the lymphangiogenesis in lung cancer of mice. Jinfukang inhibits the lung tumor mass via suppression of the BMMSCs transformation and lung tumor lymphangiogenesis. Our findings might provide the potential for the cancer therapies.

Role of TGFBIp in Wound Healing and Mucin Expression in Corneal Epithelial Cells

PURPOSE

Transforming growth factor-β-induced protein (TGFBIp) is highly expressed in the cornea, and mutant TGFBIp induces corneal diseases. However, the function of TGFBIp in cornea epithelium is not fully investigated. Here, we tested the importance of TGFBIp in regulation of gene expression and corneal epithelial cell (CEC) activity.

MATERIALS AND METHODS

The effect of TGFBIp on CEC activity was analyzed by cell migration, adhesion, proliferation and wound healing assay. Analysis of gene expression was examined by western blot and quantitative reverse transcription PCR.

RESULTS

The results demonstrated that TGFBIp increased adhesion, migration, proliferation, and wound healing of CECs. Analysis of gene expression presented that TGFBIp-stimulated CECs exhibited increased expression of mucin family genes, such as MUC1, -4, -5AC, and -16. Furthermore, TGFBIp treatment increased the expression of MUC1, -4, -5AC, -7, and -16 in conjunctival epithelial cells. TGFBIp also increased the activity of intracellular signaling molecules ERK and AKT in CECs. Using pharmacologic inhibitors of ERK and AKT, we showed that the expression of mucin genes by TGFBIp is mediated by the activation of ERK and AKT signaling.

CONCLUSION

Our findings demonstrate that the locally generated TGFBIp in the cornea may contribute to wound healing of CECs by enhancing the migration, adhesion, and proliferation of CECs. In addition, our results suggest that TGFBIp has a protective effect on ocular surfaces by inducing the expression of mucin genes in corneal and conjunctival epithelial cells. These data suggest that TGFBIp is a useful therapeutic target for patients with corneal wounds.

Insights into CCL21's roles in immunosurveillance and immunotherapy for gliomas

Chemokine (C-C) motif ligand 21 (CCL21) is involved in immunosurveillance and has recently garnered the attention of neuro-oncologists and neuroscientists. CCL21 contains an extended C-terminus, which increases binding to lymphatic glycosaminoglycans and provides a mechanism for cell trafficking by forming a stationary chemokine concentration gradient that allows cell migration via haptotaxis. CCL21 is expressed by endothelial cells of the blood-brain barrier in physiologic and pathologic conditions. CCL21 has also been implicated in leukocyte extravasation into the central nervous system. In this review, we summarize the role of CCL21 in immunosurveillance and explore its potential as an immunotherapeutic agent for the treatment of gliomas.

Lymph Nodes and Cancer Metastasis: New Perspectives on the Role of Intranodal Lymphatic Sinuses

The lymphatic system is essential for transporting interstitial fluid, soluble antigen, and immune cells from peripheral tissues to lymph nodes (LNs). Functional integrity of LNs is dependent on intact lymphatics and effective lymph drainage. Molecular mechanisms that facilitate interactions between tumor cells and lymphatic endothelial cells (LECs) during tumor progression still remain to be identified. The cellular and molecular structures of LNs are optimized to trigger a rapid and efficient immune response, and to participate in the process of tumor metastasis by stimulating lymphangiogenesis and establishing a premetastatic niche in LNs. Several molecules, e.g., S1P, CCR7-CCL19/CCL21, CXCL12/CXCR4, IL-7, IFN-γ, TGF-β, and integrin α4β1 play an important role in controlling the activity of LN stromal cells including LECs, fibroblastic reticular cells (FRCs) and follicular dendritic cells (DCs). The functional stromal cells are critical for reconstruction and remodeling of the LN that creates a unique microenvironment of tumor cells and LECs for cancer metastasis. LN metastasis is a major determinant for the prognosis of most human cancers and clinical management. Ongoing work to elucidate the function and molecular regulation of LN lymphatic sinuses will provide insight into cancer development mechanisms and improve therapeutic approaches for human malignancy.

Typing of colon and lung adenocarcinoma by high throughput imaging mass spectrometry

In advanced tumor stages, diagnosis is frequently made from metastatic tumor tissue. In some cases, the identification of the tumor of origin may be difficult by histology alone. In this setting, immunohistochemical and molecular biological methods are often required. In a subset of tumors definite diagnosis cannot be achieved. Thus, additional new diagnostic methods are required for precise tumor subtyping. Mass spectrometric methods are of special interest for the discrimination of different tumor types. We investigated whether it is possible to discern adenocarcinomas of colon and lung using high-throughput imaging mass spectrometry on formalin-fixed paraffin-embedded tissue microarrays. 101 primary adenocarcinoma of the colon and 91 primary adenocarcinoma of the lung were used to train a Linear Discriminant Analysis model. Results were validated on an independent set of 116 colonic and 75 lung adenocarcinomas. In the validation cohort 109 of 116 patients with colonic and 67 of 75 patients with lung adenocarcinomas were correctly classified. The ability to define proteomic profiles capable to discern different tumor types promises a valuable tool in cancer diagnostics and might complement current approaches. This article is part of a Special Issue entitled: MALDI Imaging, edited by Dr. Corinna Henkel and Prof. Peter Hoffmann.

The dual role of tumor lymphatic vessels in dissemination of metastases and immune response development

Lymphatic vasculature plays a crucial role in the immune response, enabling transport of dendritic cells (DCs) and antigens (Ags) into the lymph nodes. Unfortunately, the lymphatic system has also a negative role in the progression of cancer diseases, by facilitating the metastatic spread of many carcinomas to the draining lymph nodes. The lymphatics can promote antitumor immune response as well as tumor tolerance. Here, we review the role of lymphatic endothelial cells (LECs) in tumor progression and immunity and mechanism of action in the newest anti-lymphatic therapies, including photodynamic therapy (PDT).

Resveratrol Prevents Tumor Growth and Metastasis by Inhibiting Lymphangiogenesis and M2 Macrophage Activation and Differentiation in Tumor-associated Macrophages

Antitumor and antimetastatic effects of resveratrol on tumor-induced lymphangiogenesis through the regulation of M2 macrophages in tumor-associated macrophages currently remain unknown. Therefore, we herein examined the effects of resveratrol on M2 macrophage activation and differentiation, and those of resveratrol-treated condition medium (CM) in M2 macrophages on vascular endothelial cell growth factor (VEGF)-C-induced migration, invasion, and tube formation by human lymphatic endothelial cells (HLECs). Resveratrol (50 μM or 5-50 μM) inhibited the production of interleukin-10 and monocyte chemoattractant protein-1 in M2 macrophages, whereas it promoted that of transforming growth factor-β1. Resveratrol (25 and 50 μM) inhibited the phosphorylation of signal transducer and activator of transcript 3 without affecting its expression in the differentiation process of M2 macrophages. Furthermore, resveratrol-treated CM of M2 macrophages inhibited VEGF-C-induced HLEC migration, invasion, and lymphangiogenesis. Resveratrol (25 mg/kg, twice daily) inhibited tumor growth and metastasis to the lung and also reduced the area of lymphatic endothelial cells in tumors (in vivo). These results suggest that the antitumor and antimetastatic effects of resveratrol were partly due to antilymphangiogenesis through the regulation of M2 macrophage activation and differentiation.

Lithium inhibits tumor lymphangiogenesis and metastasis through the inhibition of TGFBIp expression in cancer cells

Metastasis is the main cause of mortality in cancer patients. Although there are many anti-cancer drugs targeting tumor growth, anti-metastatic agents are rarely developed. Angiogenesis and lymphangiogenesis are crucial for cancer progression; in particular, lymphangiogenesis is pivotal for metastasis in cancer. Here we report that lithium inhibits colon cancer metastasis by blocking lymphangiogenesis. Lithium reduces the expression of transforming growth factor-β-induced protein (TGFBIp) in colon cancer cells by inhibiting Smad3 phosphorylation via GSK3β inactivation. Moreover, lithium inhibits lymphatic endothelial cell migration, which is increased upon TGFBIp expression in tumor cells. Lithium had no significant effect on SW620 tumor growth in vitro and in vivo; however, it inhibited lymphangiogenesis in tumors. In tumor xenografts model, lithium was found to prevent metastasis to the lungs, liver, and lymph nodes by inhibiting TGFBIp-induced tumor lymphangiogenesis. Collectively, our findings demonstrate a novel role of lithium in the inhibition of colon cancer metastasis by blocking TGFBIp expression, and thereby TGFBIp-induced lymphangiogenesis, in primary tumors.