Talin-1 overexpression defines high risk for aggressive oral squamous cell carcinoma and promotes cancer metastasis

In vitro development of a muscle-tendon junction construct using decellularised extracellular matrix: Effect of cyclic tensile loading

The muscle tendon junction (MTJ) plays a crucial role in transmitting the force generated by muscles to the tendon and then to the bone. Injuries such as tears and strains frequently happen at the MTJ, where the regenerative process is limited due to poor vascularization and the complex structure of the tissue. Current solutions for a complete tear at the MTJ have not been successful and therefore, the development of a tissue-engineered MTJ may provide a more effective treatment. In this study, decellularised extracellular matrix (DECM) derived from sheep MTJ was used to provide a scaffold for the MTJ with the relevant mechanical properties and differentiation cues such as the relase of growth factors. Human mesenchymal stem cells (MSCs) were seeded on DECM and 10 % cyclic strain was applied using a bioreactor. MSCs cultured on DECM showed significantly higher gene and protein expression of MTJ markers such as collagen 22, paxillin and talin, than MSCs in 2D culture. Although collagen 22 protein expression was higher in the cells with strain than without strain, reduced gene expression of other MTJ markers was observed when the strain was applied. DECM combined with 10 % strain enhanced myogenic differentiation, while tenogenic differentiation was reduced when compared to static cultures of MSCs on DECM. For the first time, these results showed that DECM derived from the MTJ can induce MTJ marker gene and protein expression by MSCs, however, the effect of strain on the MTJ development in DECM culture needs further investigation.

Combination of bulk RNA sequencing and scRNA sequencing uncover the molecular characteristics of MAPK signaling in kidney renal clear cell carcinoma

The MAPK signaling pathway significantly impacts cancer progression and resistance; however, its functions remain incompletely assessed across various cancers, particularly in kidney renal clear cell carcinoma (KIRC). Therefore, there is an urgent need for comprehensive pan-cancer investigations of MAPK signaling, particularly within the context of KIRC. In this research, we obtained TCGA pan-cancer multi-omics data and conducted a comprehensive analysis of the genomic and transcriptomic characteristics of the MAPK signaling pathway. For in-depth investigation in KIRC, status of MAPK pathway was quantitatively estimated by ssGSEA and Ward algorithm was utilized for cluster analysis. Molecular characteristics and clinical prognoses of KIRC patients with distinct MAPK activities were comprehensively explored using a series of bioinformatics algorithms. Subsequently, a combination of LASSO and COX regression analyses were utilized sequentially to construct a MAPK-related signature to help identify the risk level of each sample. Patients in the C1 subtype exhibited relatively higher levels of MAPK signaling activity, which were associated with abundant immune cell infiltration and favorable clinical outcomes. Single-cell RNA sequencing (scRNA-seq) analysis of KIRC samples identified seven distinct cell types, and endothelial cells in tumor tissues had obviously higher MAPK scores than normal tissues. The immunohistochemistry results indicated the reduced expression levels of PAPSS1, MAP3K11, and SPRED1 in KIRC samples. In conclusion, our study represents the first integration of bulk RNA sequencing and single-cell RNA sequencing to elucidate the molecular characteristics of MAPK signaling in KIRC, providing a solid foundation for precision oncology.

High expression of Talin-1 is associated with tumor progression and recurrence in melanoma skin cancer patients

BACKGROUND

Talin-1 as a component of multi-protein adhesion complexes plays a role in tumor formation and migration in various malignancies. This study investigated Talin-1 in protein levels as a potential prognosis biomarker in skin tumors.

METHODS

Talin-1 was evaluated in 106 skin cancer (33 melanomas and 73 non-melanomas skin cancer (NMSC)) and 11 normal skin formalin-fixed paraffin-embedded (FFPE) tissue samples using immunohistochemical technique on tissue microarrays (TMAs). The association between the expression of Talin-1 and clinicopathological parameters, as well as survival outcomes, were assessed.

RESULTS

Our findings from data minings through bioinformatics tools indicated dysregulation of Talin-1 in mRNA levels for skin cancer samples. In addition, there was a statistically significant difference in Talin-1 expression in terms of intensity of staining, percentage of positive tumor cells, and H-score in melanoma tissues compared to NMSC (P = 0.001, P < 0.001, and P < 0.001, respectively). Moreover, high cytoplasmic expression of Talin-1 was found to be associated with significantly advanced stages (P = 0.024), lymphovascular invasion (P = 0.023), and recurrence (P = 0.006) in melanoma cancer tissues. Our results on NMSC showed a statistically significant association between high intensity of staining and the poor differentiation (P = 0.044). No significant associations were observed between Talin-1 expression levels and survival outcomes of melanoma and NMSC patients.

CONCLUSION

Our observations showed that higher expression of Talin1 in protein level may be significantly associated with more aggressive tumor behavior and advanced disease in patients with skin cancer. However, further studies are required to find the mechanism of action of Talin-1 in skin cancers.

Alterations of Cytoskeleton Networks in Cell Fate Determination and Cancer Development

Cytoskeleton proteins have been long recognized as structural proteins that provide the necessary mechanical architecture for cell development and tissue homeostasis. With the completion of the cancer genome project, scientists were surprised to learn that huge numbers of mutated genes are annotated as cytoskeletal or associated proteins. Although most of these mutations are considered as passenger mutations during cancer development and evolution, some genes show high mutation rates that can even determine clinical outcomes. In addition, (phospho)proteomics study confirms that many cytoskeleton-associated proteins, e.g., β-catenin, PIK3CA, and MB21D2, are important signaling mediators, further suggesting their biofunctional roles in cancer development. With emerging evidence to indicate the involvement of mechanotransduction in stemness formation and cell differentiation, mutations in these key cytoskeleton components may change the physical/mechanical properties of the cells and determine the cell fate during cancer development. In particular, tumor microenvironment remodeling triggered by such alterations has been known to play important roles in autophagy, metabolism, cancer dormancy, and immune evasion. In this review paper, we will highlight the current understanding of how aberrant cytoskeleton networks affect cancer behaviors and cellular functions through mechanotransduction.

Prognostic value of Talin-1 in renal cell carcinoma and its association with B7-H3

METHODS: Talin-1 protein was demonstrated as a potential prognostic marker in renal cell carcinoma (RCC) using bioinformatics analysis. We, therefore, examined the protein expression levels and prognostic significance of Talin-1 with a clinical follow-up in a total of 269 tissue specimens from three important subtypes of RCC and 30 adjacent normal samples using immunohistochemistry. Then, we used combined analysis with B7-H3 to investigate higher prognostic values. RESULTS: The results showed that high membranous and cytoplasmic expression of Talin-1 was significantly associated with advanced nucleolar grade, microvascular invasion, histological tumor necrosis, and invasion to Gerota’s fascia in clear cell RCC (ccRCC). In addition, high membranous and cytoplasmic expression of Talin-1 was found to be associated with significantly poorer disease-specific survival (DSS) and progression-free survival (PFS). Moreover, increased cytoplasmic expression of Talin-1High/B7-H3High compared to the other phenotypes was associated with tumor aggressiveness and progression of the disease, and predicted a worse clinical outcome, which may be an effective biomarker to identify ccRCC patients at high risk of recurrence and metastasis. CONCLUSIONS: Collectively, these observations indicate that Talin-1 is an important molecule involved in the spread and progression of ccRCC when expressed particularly in the cytoplasm and may serve as a novel prognostic biomarker in this subtype. Furthermore, a combined analysis of Talin-1/B7-H3 indicated an effective biomarker to predict the progression of disease and prognosis in ccRCC.

Binding blockade between TLN1 and integrin β1 represses triple-negative breast cancer

Background:

Integrin family are known as key gears in focal adhesion for triple-negative breast cancer (TNBC) metastasis. However, the integrin independent factor TLN1 remains vague in TNBC.

Methods:

Bioinformatics analysis was performed based on TCGA database and Shengjing Hospital cohort. Western blot and RT-PCR were used to detect the expression of TLN1 and integrin pathway in cells. A small-molecule C67399 was screened for blocking TLN1 and integrin β1 through a novel computational screening approach by targeting the protein-protein binding interface. Drug pharmacodynamics were determined through xenograft assay.

Results:

Upregulation of TLN1 in TNBC samples correlates with metastasis and worse prognosis. Silencing TLN1 in TNBC cells significantly attenuated the migration of tumour cells through interfering the dynamic formation of focal adhesion with integrin β1, thus regulating FAK-AKT signal pathway and epithelial-mesenchymal transformation. Targeting the binding between TLN1 and integrin β1 by C67399 could repress metastasis of TNBC.

Conclusions:

TLN1 overexpression contributes to TNBC metastasis and C67399 targeting TLN1 may hold promise for TNBC treatment.

Funding:

This study was supported by grants from the National Natural Science Foundation of China (No. 81872159, 81902607, 81874301), Liaoning Colleges Innovative Talent Support Program (Name: Cancer Stem Cell Origin and Biological Behaviour), Outstanding Scientific Fund of Shengjing Hospital (201803), and Outstanding Young Scholars of Liaoning Province (2019-YQ-10).

Increased Expression of Flightless I in Cutaneous Squamous Cell Carcinoma Affects Wnt/β-Catenin Signaling Pathway

Cutaneous squamous cell carcinoma (cSCC) accounts for 25% of cutaneous malignancies diagnosed in Caucasian populations. Surgical removal in combination with radiation and chemotherapy are effective treatments for cSCC. Nevertheless, the aggressive metastatic forms of cSCC still have a relatively poor patient outcome. Studies have linked actin cytoskeletal dynamics and the Wnt/β-catenin signaling pathway as important modulators of cSCC pathogenesis. Previous studies have also shown that the actin-remodeling protein Flightless (Flii) is a negative regulator of cSCC. The aim of this study was to investigate if the functional effects of Flii on cSCC involve the Wnt/β-catenin signaling pathway. Flii knockdown was performed using siRNA in a human late stage aggressive metastatic cSCC cell line (MET-1) alongside analysis of Flii genetic murine models of 3-methylcholanthrene induced cSCC. Flii was increased in a MET-1 cSCC cell line and reducing Flii expression led to fewer PCNA positive cells and a concomitant reduction in cellular proliferation and symmetrical division. Knockdown of Flii led to decreased β-catenin and a decrease in the expression of the downstream effector of β-catenin signaling protein SOX9. 3-Methylcholanthrene (MCA)-induced cSCC in Flii overexpressing mice showed increased markers of cancer metastasis including talin and keratin-14 and a significant increase in SOX9 alongside a reduction in Flii associated protein (Flap-1). Taken together, this study demonstrates a role for Flii in regulating proteins involved in cSCC proliferation and tumor progression and suggests a potential role for Flii in aggressive metastatic cSCC.

Proteomic Signature of Extracellular Vesicles for Lung Cancer Recognition

The proteins of extracellular vesicles (EVs) that originate from tumors reflect the producer cells' proteomes and can be detected in biological fluids. Thus, EVs provide proteomic signatures that are of great interest for screening and predictive cancer diagnostics. By applying targeted mass spectrometry with stable isotope-labeled peptide standards, we assessed the levels of 28 EV-associated proteins, including the conventional exosome markers CD9, CD63, CD81, CD82, and HSPA8, in vesicles derived from the lung cancer cell lines NCI-H23 and A549. Furthermore, we evaluated the detectability of these proteins and their abundance in plasma samples from 34 lung cancer patients and 23 healthy volunteers. The abundance of TLN1, TUBA4A, HSPA8, ITGB3, TSG101, and PACSIN2 in the plasma of lung cancer patients was measured using targeted mass spectrometry and compared to that in plasma from healthy volunteers. The most diagnostically potent markers were TLN1 (AUC, 0.95), TUBA4A (AUC, 0.91), and HSPA8 (AUC, 0.88). The obtained EV proteomic signature allowed us to distinguish between the lung adenocarcinoma and squamous cell carcinoma histological types. The proteomic cargo of the extracellular vesicles represents a promising source of potential biomarkers.

Integrated tissue proteome and metabolome reveal key elements and regulatory pathways in cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (CSCC) is a widespread malignancy but has a very low long-term survival rate for patients at the metastatic stage. Therefore, it is urgent to identify prognostic biomarkers for CSCC and improve our understanding of disease progression. Here we took advantage of a data-independent acquisition (DIA)-based nano liquid chromatography equipped with an orbitrap mass spectrometry (nLC-MS/MS) and ultraperformance LC coupled to a time-of-flight tandem MS (UPLC-TOF-MS/MS) technique to analyze cancer and corresponding noncancerous tissues from 20 CSCC patients for integrated proteomic and metabolomic analyses. Overall, 6241 tissue proteins were detected, while 136 proteins were significantly expressed in CSCC tissues. Further functional analysis revealed that various biological processes were highly enriched and participated in the pathogenesis of CSCC, especially DNA damage responses. Moreover, 641 named metabolites in total were identified, among which 181 were significantly changed in CSCC tissues. A total of 101 pathways were significantly enriched including apoptosis, autophagy, PI3K-Akt and mTOR signaling pathways. Interestingly, two pathways, protein digestion & absorption and platelet activation were both enriched in proteomic and metabolomic studies involving 5 proteins and 11 metabolites. Accordingly, a four-metabolite panel consisting of arachidonate, glutamine, glutamic acid, and proline (all area under the curve (AUC) values more than 0.9) was developed with a high accuracy (0.971) to distinguish the 20 detected cancer tissues from their noncancerous tissues. Collectively, our work highlighted the key elements and regulatory pathways involved in the pathogenesis of CSCC. More importantly, the present study not only provided potential biomarkers for the early diagnosis of CSCC, but also expanded our knowledge of the physiopathology of the disease. SIGNIFICANCE: CSCC is the second most common human cancer but has few treatment options and few sensitive biomarkers for diagnosis. Here we comprehensively revealed its molecular characteristics by performing integrated tissue proteomic and metabolomic analyses. Significantly distinct profiles and certain enriched pathways including DNA damage responses were identified as associated with CSCC. Moreover, protein digestion & absorption and platelet activation were both enriched in the proteome and metabolome. These identified molecular changes probably play significant roles in CSCC development. Finally, we developed a four-metabolite panel to distinguish CSCC with high accuracy. Overall, our data not only provided potential diagnostic biomarkers, but also extended knowledge on the pathogenesis of CSCC.

Upregulated Talin1 synergistically boosts β-estradiol-induced proliferation and pro-angiogenesis of eutopic and ectopic endometrial stromal cells in adenomyosis

Adenomyosis (ADS) is an estrogen-dependent gynecological disease with unspecified etiopathogenesis. Local hyperestrogenism may serve a key role in contributing to the origin of ADS. Talin1 is mostly identified to be overexpressed and involved in the progression of numerous human carcinomas through mediating cell proliferation, adhesion and motility. Whether Talin1 exerts an oncogenic role in the pathogenesis of ADS and puts an extra impact on the efficacy of estrogen, no relevant data are available yet. Here we demonstrated that the adenomyotic eutopic and ectopic endometrial stromal cells (ADS_Eu_ESC and ADS_Ec_ESC) treated with β-estradiol (β-E₂) presented stronger proliferative and pro-angiogenetic capacities, accompanied by increased expression of PCNA, Ki67, VEGFB and ANGPTL4 proteins. Meanwhile, these promoting effects were partially abrogated by Fulvestrant (ICI 182780, an estrogen-receptor antagonist). Aberrantly upregulation of Talin1 mRNA and protein level was observed in ADS endometrial specimens and stromal cells. Through performing functional experiments in vitro, we further determined that merely overexpression of Talin1 (OV-Talin1) also enhanced ADS stromal cell proliferation and pro-angiogenesis, while the most pronounced facilitating effects were found in the co-intervention group of OV-Talin1 plus β-E₂ treatment. Results from the xenograft nude mice model showed that the hypodermic endometrial lesions from co-intervention group had the highest mean weight and volume, compared with that of individual OV-Talin1 or β-E₂ treatment. The expression levels of PCNA, Ki67, VEGFB and ANGPTL4 in the lesions were correspondingly elevated the most in the co-intervention group. Our findings unveiled that overexpressed Talin1 might cooperate withβ-E₂ in stimulating ADS endometrial stromal cell proliferation and neovascularization, synergistically promoting the growth and survival of ectopic lesions. These results may be beneficial to provide a new insight for clarifying the pathogenesis of ADS.

Expression of Talin-1 in endometriosis and its possible role in pathogenesis

BACKGROUND

Endometriosis is a disease that involves active cell invasion and migration. Talin-1 can promote cell invasion, migration and adhension in various cancer cells, but its role in endometriosis has not been investigated. This study was to investigate the expression level of Talin-1 in endometriosis and the role of Talin-1 in the proliferation, adhesion, migration, and invasion of human endometrial stromal cells (ESCs).

METHODS

Ectopic and eutopic endometrial tissues were collected from women with endometriosis, and the control endometrial tissues were obtained from patients without endometriosis. The expression level of Talin-1 was detected in each sample using quantitative real-time polymerase chain reaction and immunohistochemistry. The expression of Talin-1 was inhibited using RNA interference in ESCs, and its proliferation, apoptosis, adhesion, migration, and invasion capacity were analyzed. Western blotting was performed to detect the expression of related molecules after the downregulation of Talin-1.

RESULTS

The results showed that the mRNA and protein expression of Talin-1 were significantly increased in the ectopic endometrium and eutopic endometrial tissues compared with the controls. The knockdown of Talin-1 did not affect the proliferation and apoptosis of ESCs. The results indicated that the downexpression of Talin-1 inhibited the adhesion, invasion, and migration of ESCs. In addition, the expressions of N-cadherin, MMP-2, and integrin β3 were significantly lower after the deregulation of Talin-1, whereas the levels of E-cadherin were significantly increased.

CONCLUSIONS

The expression of Talin-1 was increased in the ectopic and eutopic endometrial tissues compared with the control endometrium. The downregulation of Talin-1 inhibited the adhesion, invasion, and migration of ESCs.

The prospects of nanotherapeutic approaches for targeting tumor-associated macrophages in oral cancer

OSCC (oral squamous cell carcinoma) is currently one of the most formidable cancers plagued by challenges like low overall survivability, lymph node associated metastasis, drug resistance, and poor diagnostics. The tumor microenvironment (TME) and its constituent stromal elements are crucial modulators of tumor growth and treatment response, more specifically so with regards to resident tumor associated macrophages (TAMs) and their liaison with the different stromal elements in the tumor niche (Figure 1). Interestingly, there isn't much information on TAM-targeted nanotherapy in OSCC where the first line of therapeutics for oral cancer is surgery with other therapeutics such as chemo- and radiotherapy acting only as adjuvant therapy for oral cancer. In the face of this real time situation, there have been some successful attempts at targeted therapy for OSCC cells and we believe they might elicit favorable responses against TAMs as well. Demanding our immediate attention, this review intends to provide a glimpse of the prevailing anti-TAM treatment strategies, which present great prospect for an uncharted territory like OSCC.

Elevated Circular RNA PVT1 Promotes Eutopic Endometrial Cell Proliferation and Invasion of Adenomyosis via miR-145/Talin1 Axis

Several theories on the origin of adenomyosis (ADS) have been proposed, of which the most widely accepted is the fundamental pathogenic role of uterine eutopic endometrium. Emerging evidence suggests that circular RNAs participate in the multiple tumorgenesis. The vital importance of circular RNA PVT1 (circPVT1) in the pathological progress like malignancies has been well documented. Nevertheless, its underlying correlation with ADS remains elusive yet. The purpose of this study was to investigate the expression pattern, regulatory effect, and internal mechanism of circPVT1 in ADS. qRT-PCR was performed to detect the relative mRNA expression of circPVT1, miR-145, and Talin1 in ADS endometrial tissue and cells. The protein level of Talin1 was measured by Western blot and immunochemistry. Immunofluorescence was used to identify the primary endometrial epithelial and stromal cells. circPVT1 knockdown in vitro was achieved by transfecting with specific lentivirus vector CCK-8, and colony formation assays were utilized to assess cell proliferation; meanwhile, the transwell assay was employed for evaluating cell invasion ability. By conducting bioinformatics, dual-luciferase reporter assay, or RNA immunoprecipitation (RIP) experiment, the interaction between miR-145 and circPVT1 or Talin1 was verified. Rescue experiments further determined the regulatory effect of circPVT1/miR-145/Talin1 axis. We found both circPVT1 and Talin1 were markedly upregulated in ADS endometrial tissue and cells, whereas miR-145 was decreased. Elevated expression of circPVT1 was closely related to the severity of dysmenorrhea, menorrhagia, and uterine enlargement of patients with ADS. Knockdown of circPVT1 inhibited adenomyotic epithelial and stromal cell proliferation and invasion. Further mechanistic experiments revealed that circPVT1 negatively regulated miR-145 through serving as a molecular sponge. And the facilitating effect of circPVT1 was partially reversed by miR-145. Talin1 was demonstrated to be a down target of miR-145 and indirectly affected by circPVT1. Our findings unveiled that enhanced circPVT1 may be involved in the pathogenesis of ADS via stimulating endometrial cell proliferation and invasion. The establishment of circPVT1/miR-145/Talin1 pathway might present a novel therapeutic insight for ADS.

Proteomics and molecular network analyses reveal that the interaction between the TAT-DCF1 peptide and TAF6 induces an antitumor effect in glioma cells

Glioblastoma is the most lethal brain cancer in adults. Despite advances in surgical techniques, radiotherapy, and chemotherapy, their therapeutic effect is far from significant, since the detailed underlying pathological mechanism of this cancer is unclear. The establishment of molecular interaction networks has laid the foundation for the exploration of these mechanisms with a view to improving therapy for glioblastoma. In the present study, to further explore the cellular role of DCF1 (dendritic cell-derived factor 1), the proteins bound to TAT-DCF1 (transactivator of transcription-dendritic cell-derived factor 1) were identified, and biosystem analysis was employed. Functional enrichment analyses indicate that TAT-DCF1 induced important biological changes in U251 cells. Furthermore, the established molecular interaction networks indicated that TAT-DCF1 directly interacted with TAF6 in glioma cells and with UBC in HEK293T (human embryonic kidney 293T) cells. In addition, further biological experiments demonstrate that TAT-DCF1 induced the activation of the RPS27A/TOP2A/HMGB2/BCL-2 signaling pathway via interaction with TAF6 in U251 cells. Taken together, these findings suggest that the TAT-DCF1 peptide possesses great potential for the development of glioblastoma therapy through the interaction with TAF6-related pathways and provides further theoretic evidence for the mechanisms underlying the antitumor effects of TAT-DCF1.

Cancer associated talin point mutations disorganise cell adhesion and migration

Talin-1 is a key component of the multiprotein adhesion complexes which mediate cell migration, adhesion and integrin signalling and has been linked to cancer in several studies. We analysed talin-1 mutations reported in the Catalogue of Somatic Mutations in Cancer database and developed a bioinformatics pipeline to predict the severity of each mutation. These predictions were then assessed using biochemistry and cell biology experiments. With this approach we were able to identify several talin-1 mutations affecting integrin activity, actin recruitment and Deleted in Liver Cancer 1 localization. We explored potential changes in talin-1 signalling responses by assessing impact on migration, invasion and proliferation. Altogether, this study describes a pipeline approach of experiments for crude characterization of talin-1 mutants in order to evaluate their functional effects and potential pathogenicity. Our findings suggest that cancer related point mutations in talin-1 can affect cell behaviour and so may contribute to cancer progression.

Cyclin F Downregulation Affects Epithelial-Mesenchymal Transition Increasing Proliferation and Migration of the A-375 Melanoma Cell Line

Background

Cyclins are well-known cell cycle regulators. The activation of cyclin-dependent kinases by cyclins allows orchestration of the complicated cell cycle machinery and drives the cell from the G1 phase to the end of the mitotic phase. In recent years, it has become evident that cyclins are involved in processes beyond the cell cycle. Cyclin F does not activate CDKs but forms part of the Skp1-Cul1-F-box (SCF) complex where it is responsible for protein target recognition and subsequent degradation in a proteasome-dependent manner.

Results

Here, we report that the downregulation of cyclin F in the A-375 melanoma cell line increases cell viability and colony formation in a cell cycle independent manner. Lower levels of cyclin F do not appear to affect the cell cycle, based on flow cytometry measuring BrdU incorporation and propidium iodide staining. By means of immunofluorescence staining and Western blot analysis, we observed changes in cell morphology-related markers which suggested ongoing epithelial-mesenchymal transition (EMT) in response to cyclin F downregulation. Increases in vimentin and N-cadherin protein levels, decreases in levels of epithelial markers such as ZO-1, along with changes in morphology to a spindle-like shape with the appearance of actin stress fibers, are all hallmarks of EMT. These changes are associated with increased invasive and migratory potential, based on 2D migration assays. Moreover, we observe an increase in RhoABC, talin and paxillin levels, the proteins involved in controlling cell signaling and motility. Lastly, upon knocking down cyclin F expression, we observed a decrease in thrombospondin-1 expression, suggesting a role of cyclin F in angiogenesis.

Conclusion

Cyclin F depletion induces proliferation and EMT processes in the A-375 melanoma model.

Talin-1; other than a potential marker for hepatocellular carcinoma diagnosis

BACKGROUND AND STUDY AIMS

Hepatocellular carcinoma (HCC) is a major cause of cancer mortality worldwide. Talin-1 was previously proposed as a potential novel biomarker for HCC diagnosis but with limited and inconsistent data. We aimed to study the possible role of talin-1 in diagnosis and prognostic stratification of patients with hepatocellular carcinoma.

PATIENTS AND METHODS

Ninety-six patients were recruited and classified into three groups; 1) cirrhosis group: 40 patients with liver cirrhosis, 2) HCC group: 40 patients with HCC, 3) control group: 16 healthy volunteers with matched age and sex. Serum talin-1 level was detected using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The highest levels of talin-1 were observed among the HCC group followed by cirrhosis then control groups (p = 0.000). In the HCC group, a significant correlation was found between talin-1 and each of multifocal HCC (p = 0.013), portal vein invasion (p = 0.022) and presence of ascites (p = 0.001), while no significant correlation was detected with tumour foci size (p = 0.605). For HCC detection, talin-1 had AUC = 0.858, 100% sensitivity and 65% specificity, while AFP had AUC = 1.000, 100% sensitivity and specificity.

CONCLUSION

Talin-1 is a potential marker for diagnosis and prognostic assessment of HCC. Further studies are needed to investigate the ultimate diagnostic and prognostic utility of serum talin-1.

Talin-1 Gene Expression as a Tumor Marker in Hepatocellular Carcinoma Patients: A Pilot Study

Background & Aims:

Hepatocellular Carcinoma (HCC) is the most common primary liver tumor. It is the second most common cancer in men and the sixth in women in Egypt. One of the proteins participating in the trans-endothelial migration is Talin-1. It also has a role in the formation and metastasis of different types of cancer. This study aimed to evaluate the diagnostic impact of Talin-1 gene expression in HCC Egyptian patients.

Methods:

Our study included forty HCC patients, thirty liver cirrhosis patients without HCC and thirty healthy subjects. For all groups, clinical and biochemical parameters were investigated. Tumor characteristics were assessed and tumor staging was done using Okuda, CLIP, VISUM and Tokyo staging systems. In addition, Serum Alpha-Fetoprotein (AFP) levels were assayed using Enzyme Immunoassay (EIA) and Talin-1 gene expression was assessed in the Peripheral Blood Mononuclear Cells (PBMCs) via quantitative real-time Polymerase Chain Reaction (PCR).

Results:

Talin-1 gene expression was significantly upregulated in HCC patients in comparison to cirrhotic and control subjects. The Receiver Operating Characteristic (ROC) analysis indicated that Talin-1 gene expression surpasses serum levels of AFP in the diagnosis of HCC. In particular, the cut off value of 9.5 (2-∆∆Ct) recorded an AUC of 85.7% with a sensitivity of 93.3% and specificity of 80%.

Conclusion:

Our data confirmed an évident diagnostic role of Talin-1 gene expression for HCC detection.

Feeling Things Out: Bidirectional Signaling of the Cell-ECM Interface, Implications in the Mechanobiology of Cell Spreading, Migration, Proliferation, and Differentiation

Biophysical cues stemming from the extracellular environment are rapidly transduced into discernible chemical messages (mechanotransduction) that direct cellular activities-placing the extracellular matrix (ECM) as a potent regulator of cell behavior. Dynamic reciprocity between the cell and its associated matrix is essential to the maintenance of tissue homeostasis and dysregulation of both ECM mechanical signaling, via pathological ECM turnover, and internal mechanotransduction pathways contribute to disease progression. This review covers the current understandings of the key modes of signaling used by both the cell and ECM to coregulate one another. By taking an outside-in approach, the inherent complexities and regulatory processes at each level of signaling (ECM, plasma membrane, focal adhesion, and cytoplasm) are captured to give a comprehensive picture of the internal and external mechanoregulatory environment. Specific emphasis is placed on the focal adhesion complex which acts as a central hub of mechanical signaling, regulating cell spreading, migration, proliferation, and differentiation. In addition, a wealth of available knowledge on mechanotransduction is curated to generate an integrated signaling network encompassing the central components of the focal adhesion, cytoplasm and nucleus that act in concert to promote durotaxis, proliferation, and differentiation in a stiffness-dependent manner.

Long Noncoding RNA Lnc-TLN2-4:1 Suppresses Gastric Cancer Metastasis and Is Associated with Patient Survival

Gastric cancer (GC) is one of the most common malignancies worldwide, and the tumor metastasis leads to poor outcomes of GC patients. Long noncoding RNAs (lncRNAs) have emerged as new regulatory molecules that play a crucial role in tumor metastasis. However, the biological function and underlying mechanism of numerous lncRNAs in GC metastasis remain largely unclear. Here, we report a novel lncRNA, lnc-TLN2-4:1, whose expression is decreased in GC tissue versus matched normal tissue, and its low expression is involved in the lymph node and distant metastases of GC, as well as poor overall survival rates of GC patients. We further found that lnc-TLN2-4:1 inhibits the ability of GC cells to migrate and invade but does not influence GC cell proliferation and confirmed that lnc-TLN2-4:1 is mainly located in the cytoplasm of GC cells. We then found that lnc-TLN2-4:1 increases the mRNA and protein expression of TLN2 in GC cells and there is a positive correlation between the expression of lnc-TLN2-4:1 and TLN2 mRNA in GC tissue. Collectively, we identified a novel lncRNA, lnc-TLN2-4:1, in GC, where lnc-TLN2-4:1 represses cell migration and invasion. The low expression of lnc-TLN2-4:1 is associated with poor overall survival rates of GC patients. These suggest that lnc-TLN2-4:1 may be a tumor suppressor during GC metastasis.

Talin1 knockdown prohibits the proliferation and migration of colorectal cancer cells via the EMT signaling pathway

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second highest cause of cancer-associated death worldwide. Talin1 activates integrins, which mediate cell adhesion, proliferation, tumorigenesis and metastasis. The aim of the present study was to determine talin1 expression levels in colorectal cancer (CRC) and investigate the role of talin1 in CRC proliferation and invasion in vitro and in vivo. Talin1 protein expression levels were detected in human CRC and adjacent normal tissues by immunohistochemistry. Talin1 short hairpin RNA and control vectors were designed and stably transfected into HCT116 CRC cells. Cell proliferation was determined by MTT assay. Cell migratory and invasive capabilities were detected by wound-healing and Matrigel invasion assays. The expression of proteins in the epithelial-to-mesenchymal transition signaling pathway was determined by western blotting and reverse transcription-quantitative PCR. The effect of talin1 on tumor growth was explored in vivo using BALB/c nude mice. Immunohistochemical analysis of CRC and adjacent normal tissue revealed that talin1 expression was upregulated in CRC. Talin1 knockdown significantly reduced the proliferation, migration and invasive ability of HCT116 cells compared with the control. Protein levels of phosphorylated STAT3 and vimentin were significantly lower in talin1-knockdown HCT116 cell lines compared with the control, whereas protein levels of E-cadherin were increased. Interleukin-6 mRNA levels were significantly increased in patients' blood samples compared with blood samples from healthy controls, as well as in CRC compared with adjacent normal tissue. In vivo experiments demonstrated that talin1 knockdown reduced CRC tumor growth and weight in nude mice. In conclusion, Talin1 knockdown may prevent the proliferation and migration of CRC cells by downregulating various factors involved in the epithelial-to-mesenchymal transition process, such as phosphorylated STAT3 and vimentin; therefore, talin1 may provide a novel therapeutic target for CRC.

Phosphoproteomic Profiling Identifies Aberrant Activation of Integrin Signaling in Aggressive Non-Type Bladder Carcinoma

Bladder carcinoma is highly heterogeneous and its complex molecular landscape; thus, poses a significant challenge for resolving an effective treatment in metastatic tumors. We computed the epithelial-mesenchymal transition (EMT) scores of three bladder carcinoma subtypes—luminal, basal, and non-type. The EMT score of the non-type indicated a “mesenchymal-like” phenotype, which correlates with a relatively more aggressive form of carcinoma, typified by an increased migration and invasion. To identify the altered signaling pathways potentially regulating this EMT phenotype in bladder cancer cell lines, we utilized liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based phosphoproteomic approach. Bioinformatics analyses were carried out to determine the activated pathways, networks, and functions in bladder carcinoma cell lines. A total of 3125 proteins were identified, with 289 signature proteins noted to be differentially phosphorylated (p ≤ 0.05) in the non-type cell lines. The integrin pathway was significantly enriched and five major proteins (TLN1, CTTN, CRKL, ZYX and BCAR3) regulating cell motility and invasion were hyperphosphorylated. Our study reveals GSK3A/B and CDK1 as promising druggable targets for the non-type molecular subtype, which could improve the treatment outcomes for aggressive bladder carcinoma.

YWHAZ amplification/overexpression defines aggressive bladder cancer and contributes to chemo-/radio-resistance by suppressing caspase-mediated apoptosis

The objective of this study was to characterize the oncogenic actions of a recently identified cancer‐associated gene YWHAZ (also named as 14‐3‐3 ζ/δ) in urothelial carcinomas of the urinary bladder (UCUB). A genome‐wide study revealed YWHAZ to be involved in the amplicon at 8q22.3, and its genetic amplification was detected predominantly in muscle‐invasive bladder cancer (MIBC). Immunohistochemical staining confirmed the association of YWHAZ overexpression with higher tumor stages, lymph node/vascular invasion, and mitotic activity. Univariate and multivariate analyses further indicated the prognostic potential of YWHAZ for more aggressive cancer types. Both gene set enrichment analysis and STRING network studies suggested involvement of YWHAZ in regulating caspase‐mediated apoptosis. Ectopic expression of YWHAZ in bladder cells with low endogenous YWHAZ levels boosted cell resistance to doxorubicin and cisplatin, as well as to ionizing radiation. Conversely, YWHAZ‐knockdown using specific shRNA in cells with high endogenous YWHAZ levels diminished survival activity, suppressing cell growth and increasing cell death. Our findings confirm the essential role played by YWHAZ in sustaining cell proliferation during chemo/radiotherapy. Treatments based on anti‐YWHAZ strategies may thus be beneficial for UCUB patients overexpressing YWHAZ. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Every step of the way: integrins in cancer progression and metastasis

Cell adhesion to the extracellular matrix is fundamental to tissue integrity and human health. Integrins are the main cellular adhesion receptors that through multifaceted roles as signalling molecules, mechanotransducers and key components of the cell migration machinery are implicated in nearly every step of cancer progression from primary tumour development to metastasis. Altered integrin expression is frequently detected in tumours, where integrins have roles in supporting oncogenic growth factor receptor (GFR) signalling and GFR-dependent cancer cell migration and invasion. In addition, integrins determine colonization of metastatic sites and facilitate anchorage-independent survival of circulating tumour cells. Investigations describing integrin engagement with a growing number of versatile cell surface molecules, including channels, receptors and secreted proteins, continue to lead to the identification of novel tumour-promoting pathways. Integrin-mediated sensing, stiffening and remodelling of the tumour stroma are key steps in cancer progression supporting invasion, acquisition of cancer stem cell characteristics and drug resistance. Given the complexity of integrins and their adaptable and sometimes antagonistic roles in cancer cells and the tumour microenvironment, therapeutic targeting of these receptors has been a challenge. However, novel approaches to target integrins and antagonism of specific integrin subunits in stringently stratified patient cohorts are emerging as potential ways forward.

Breaking down Leukemia Walls: Heteronemin, a Sesterterpene Derivative, Induces Apoptosis in Leukemia Molt4 Cells through Oxidative Stress, Mitochondrial Dysfunction and Induction of Talin Expression

Heteronemin, the most abundant secondary metabolite in the sponge Hippospongia sp., exhibited potent cytotoxic activity against several cancer cell lines. It increased the percentage of apoptotic cells and reactive oxygen species (ROS) in Molt4 cells. The use of ROS scavenger, N-acetyl cysteine (NAC), suppressed both the production of ROS from mitochondria and cell apoptosis that were induced by heteronemin treatment. Heteronemin upregulated talin and phosphorylated talin expression in Molt4 cells but it only upregulated the expression of phosphorylated talin in HEK293 cells. However, pretreatment with NAC reversed these effects. Talin siRNA reversed the activation of pro-apoptotic cleaved caspases 3 and 9. On the other hand, the downstream proteins including FAK and NF-κB (p65) were not affected. In addition, we confirmed that heteronemin directly modulated phosphorylated talin expression through ROS generation resulting in cell apoptosis, but it did not affect talin/FAK complex. Furthermore, heteronemin interfered with actin microfilament and caused morphology changes. Taken together, these findings suggest that the cytotoxic effect of heteronemin is associated with oxidative stress and induction of phosphorylated talin expression. Our results suggest that heteronemin represents an interesting candidate which can be further developed as a drug lead against leukemia.

Quantitative proteomic analysis of pancreatic cyst fluid proteins associated with malignancy in intraductal papillary mucinous neoplasms

Background

The application of advanced imaging technologies for identifying pancreatic cysts has become widespread. However, accurately differentiating between low-grade dysplasia (LGD), high-grade dysplasia (HGD), and invasive intraductal papillary mucinous neoplasms (IPMNs) remains a diagnostic challenge with current biomarkers, necessitating the development of novel biomarkers that can distinguish IPMN malignancy.

Methods

Cyst fluid samples were collected from nine IPMN patients (3 LGD, 3 HGD, and 3 invasive IPMN) during their pancreatectomies. An integrated proteomics approach that combines filter-aided sample preparation, stage tip-based high-pH fractionation, and high-resolution MS was applied to acquire in-depth proteomic data of pancreatic cyst fluid and discover marker candidates for IPMN malignancy. Biological processes of differentially expressed proteins that are related to pancreatic cysts and aggressive malignancy were analyzed using bioinformatics tools such as gene ontology analysis and Ingenuity pathway analysis. In order to confirm the validity of the marker candidates, 19 cyst fluid samples were analyzed by western blot.

Results

A dataset of 2992 proteins was constructed from pancreatic cyst fluid samples. A subsequent analysis found 2963 identified proteins in individual samples, 2837 of which were quantifiable. Differentially expressed proteins between histological grades of IPMN were associated with pancreatic diseases and malignancy according to ingenuity pathway analysis. Eighteen biomarker candidates that were differentially expressed across IPMN histological grades were discovered—7 DEPs that were upregulated and 11 that were downregulated in more malignant grades. HOOK1 and PTPN6 were validated by western blot in an independent cohort, the results of which were consistent with our proteomic data.

Conclusions

This study demonstrates that novel biomarker candidates for IPMN malignancy can be discovered through proteomic analysis of pancreatic cyst fluid.

Electronic supplementary material

The online version of this article (10.1186/s12014-018-9193-1) contains supplementary material, which is available to authorized users.

Acidic leucine-rich nuclear phosphoprotein-32A (ANP32A) association with lymph node metastasis predicts poor survival in oral squamous cell carcinoma patients

Acidic leucine-rich nuclear phosphoprotein-32A (ANP32A) is a multifunctional protein aberrantly expressed in various types of cancers. However, its expression pattern and clinical significance in oral squamous cell carcinoma (OSCC) remains unclear. In this study, we immunohistochemically investigated the expression pattern of ANP32A in 259 OSCC patients and the results were correlated with clinicopathological factors using Allred, Klein and Immunoreactive scoring (IRS) system. Our data indicated that high expression of ANP32A was significantly associated with N stage and tumor differentiation status in OSCC patients. High ANP32A expression with N2/N3 stage had an increased mortality risk than low ANP32A expressing OSCC patients with N0/N1 stage. Functional studies revealed that knockdown of ANP32A significantly decreased the migration and invasion ability thereby concomitantly increasing E-cadherin and decreasing Slug, Claudin-1 and Vimentin expression in vitro. These results suggest that ANP32A is commonly increased in oral squamous cell carcinoma and ANP32A protein could act as a potential biomarker for prognosis assessment of oral cancer patients with lymph node metastasis.

Downregulation of Talin1 promotes hepatocellular carcinoma progression through activation of the ERK1/2 pathway

Talin1 is an adaptor protein that conjugates integrins to the cytoskeleton and regulates integrins and focal adhesion signaling. Several studies have found that Talin1 is overexpressed in several tumor types and promotes tumor progression. However, the explicit role of Talin1 in hepatocellular carcinoma (HCC) progression is still unclear and its functional mechanism remains largely unknown. In this study, we showed a trend of gradually decreasing expression of Talin1 from normal liver tissues to hepatocirrhosis, liver hyperplasia, the corresponding adjacent non‐tumor, primary HCC, and eventually metastatic foci, indicating that Talin1 may correlate with HCC initiation to progression. Talin1 was significantly downregulated in HCC tissues compared with adjacent non‐tumor tissues and low Talin1 expression was associated with HCC progression and poor prognosis. Furthermore, Talin1 knockdown induced epithelial–mesenchymal transition and promoted migration and invasion in SK‐Hep‐1 cells and HepG2 cells. Mechanistically, we found that the ERK pathway was responsible for these promoting effects of Talin1 knockdown in HCC cells. The promoting effects of Talin1 knockdown on epithelial–mesenchymal transition, migration, and invasion were reversed by U0126, a specific ERK1/2 inhibitor. Taken together, our results suggested that Talin1 might serve as a tumor suppressor in HCC and a potential prognostic biomarker for HCC patients.

Differential Protein Expression Marks the Transition From Infection With Opisthorchis viverrini to Cholangiocarcinoma

Parts of Southeast Asia have the highest incidence of intrahepatic cholangiocarcinoma (CCA) in the world because of infection by the liver fluke Opisthorchis viverrini (Ov). Ov-associated CCA is the culmination of chronic Ov-infection, with the persistent production of the growth factors and cytokines associated with persistent inflammation, which can endure for years in Ov-infected individuals prior to transitioning to CCA. Isobaric labeling and tandem mass spectrometry of liver tissue from a hamster model of CCA was used to compare protein expression profiles from inflammed tissue (Ovinfected but not cancerous) versus cancerous tissue (Ov-induced CCA). Immunohistochemistry and immunoblotting were used to verify dysregulated proteins in the animal model and in human tissue. We identified 154 dysregulated proteins that marked the transition from Ov-infection to Ov-induced CCA, i.e. proteins dysregulated during carcinogenesis but not Ov-infection. The verification of dysregulated proteins in resected liver tissue from humans with Ov-associated CCA showed the numerous parallels in protein dysregulation between human and animal models of Ov-induced CCA. To identify potential circulating markers for CCA, dysregulated proteins were compared with proteins isolated from exosomes secreted by a human CCA cell line (KKU055) and 27 proteins were identified as dysregulated in CCA and present in exosomes. These data form the basis of potential diagnostic biomarkers for human Ov-associated CCA. The profile of protein dysregulation observed during chronic Ovinfection and then in Ov-induced CCA provides insight into the etiology of an infection-induced inflammation-related cancer.

Effect of talin1 on apoptosis in hepatoma carcinoma cells via the PI3K/Akt/NF-κB signaling pathway

Talin1 is implicated in many cellular processes, which has been studied in various diseases using molecular biological technology.

Upregulation of Talin-1 expression associates with advanced pathological features and predicts lymph node metastases and biochemical recurrence of prostate cancer

Talin-1 functions to regulate cell-cell adhesion, and its altered expression was reported to be associated with human carcinogenesis.A total of 280 tissue specimens from prostate cancer (PCa) patients who underwent radical prostatectomy, 75 cases of benign prostatic hyperplasia (BPH) tissue, and 6 cases of normal prostate tissue specimens were collected for construction of tissue microarray and subsequently subjected to immunohistochemical staining of Talin-1 expression.Talin-1 expression was significantly higher in PCa than both normal and BPH tissues (P <0.001). Talin-1 expression in PCa tissues was associated with preoperative prostate-specific antigen (PSA) level, Gleason score, tumor stage, lymph node metastasis, positive surgical margin, extracapsular extension and seminal vesicle invasion (all P <0.05). Logistic regression analysis showed that Talin-1 and Gleason score were independent risk factors for lymph node metastasis of PCa (P <0.001). Receiver operating characteristic (ROC) curve indicated that Talin-1 expression (AUC = 0.766) had a better accuracy to predict PCa lymph node metastasis than Gleason score (AUC = 0.697), whereas their combination could further enhance the prediction accuracy (AUC = 0.803). Kaplan-Meier curve analysis showed that increased Talin-1 expression was associated with shortened biochemical-free survival of PCa patients after radical prostatectomy (P <0.001).These findings suggested that Talin-1 protein was significantly upregulated in PCa tissues compared with that of BPH tissue and Talin-1 expression was an independent predictor for lymph node metastasis and biochemical recurrence of PCa. Further study will investigate the underlying molecular mechanism and the role of Talin-1 in PCa.

LC-MS analysis of Hep-2 and Hek-293 cell lines treated with Brazilian red propolis reveals differences in protein expression

Objective

Red propolis, an exclusive variety of propolis found in the northeast of Brazil has shown to present antitumour activity, among several other biological properties. This article aimed to help to evaluate the underlying molecular mechanisms of the potential anticancer effects of red propolis on tumour, Hep-2, and non-tumour cells, Hek-293.

Methods

Differentially expressed proteins in human cell lines were identified through label-free quantitative MS-based proteomic platform, and cells were stained with Giemsa to show morphological changes.

Key findings

A total of 1336 and 773 proteins were identified for Hep-2 and Hek-293, respectively. Among the proteins here identified, 16 were regulated in the Hep-2 cell line and 04 proteins in the Hek-293 line. Over a total of 2000 proteins were identified under MS analysis, and approximately 1% presented differential expression patterns. The GO annotation using Protein Analysis THrough Evolutionary Relationships classification system revealed predominant molecular function of catalytic activity, and among the biological processes, the most prominent was associated to cell metabolism.

Conclusion

The proteomic profile here presented should help to elucidate further molecular mechanisms involved in inhibition of cancer cell proliferation by red propolis, which remain unclear to date.

Increased expression of Talin1 in the eutopic and ectopic endometria of women with adenomyosis

Adenomyosis is a prevalent gynecologic benign disease in women. Despite its significance, there is only a limited understanding of its pathological mechanisms. Talin1, a cytoskeletal protein, plays an important role in cell survival, proliferation, invasion and migration. The objective of this study was to investigate the mRNA and protein expression of talin1 in both the eutopic and ectopic endometria of women with adenomyosis. Higher talin1 mRNA levels were observed in both ectopic and eutopic endometria from the adenomyosis subjects compared with the eutopic endometria from women without adenomyosis. Immunohistochemistry revealed increased epithelial expression of talin1 in the ectopic and eutopic endometria from patients with adenomyosis compared with those without adenomyosis. When tests were performed on matched samples of eutopic and ectopic endometria of adenomyosis subjects, the mRNA and protein expression of talin1 was much higher in the ectopic endometria than in the eutopic endometria. The results reveal that the expression pattern of talin1 in the eutopic and ectopic endometria is enhanced in women with adenomyosis. Increased talin1 expression may play a role in the pathogenesis and development of adenomyosis.

Identification of 14-3-3zeta associated protein networks in oral cancer

Advancements in genomics, proteomics, and bioinformatics have improved our understanding of gene/protein networks involved in intra- and intercellular communication and tumor-host interactions. Using proteomics integrated with bioinformatics, previously we reported overexpression of 14-3-3ζ in premalignant oral lesions and oral squamous cell carcinoma tissues in comparison with normal oral epithelium. 14-3-3ζ emerged as a novel molecular target for therapeutics and a potential prognostic marker in oral squamous cell carcinoma patients. However, the role of 14-3-3ζ in development and progression of oral cancer is not known yet. This study aimed to identify the 14-3-3ζ associated protein networks in oral cancer cell lines using IP-MS/MS and bioinformatics. A total of 287 binding partners of 14-3-3ζ were identified in metastatic (MDA1986) and nonmetastatic (SCC4) oral cancer cell lines including other 14-3-3 isoforms (2%), proteins involved in apoptosis (2%), cytoskeleton (9%), metabolism (16%), and maintenance of redox potential (2%). Our bioinformatics analysis revealed involvement of 14-3-3ζ in protein networks regulating cell cycle, proliferation, apoptosis, cellular trafficking, and endocytosis in oral cancer. In conclusion, our data revealed several novel protein interaction networks involving 14-3-3ζ in oral cancer progression and metastasis.

Both Talin-1 and Talin-2 correlate with malignancy potential of the human hepatocellular carcinoma MHCC-97 L cell

Background

Talin-1 (TLN-1) and TLN-2 are implicated in many cellular processes, but their roles in hepatocellular carcinoma (HCC) remain unclear. This study aimed to assess cell cycle distribution, anoikis, invasion and migration in human HCC MHCC-97 L cells.

Methods

MHCC-97 L cells, which highly express TLN-1, were transduced with TLN-1 shRNA (experimental group) or scramble shRNA (negative control group); non-transduced MHCC-97 L cells were used as blank controls. TLN-1 and TLN-2 mRNA and protein levels were detected by real-time RT-PCR and western blot, respectively. Then, cell cycle distribution and anoikis were assessed by flow cytometry. In addition, migration and invasion abilities were assessed using Transwell and cell scratch assays. Finally, a xenograft nude mouse model was established to further assess cell tumorigenicity.

Results

Compared with the blank and negative control groups, TLN-1/2 mRNA and protein levels were significantly reduced in the experiment group. TLN-1/2 knockdown cells showed significantly more cells in the G0/G1 phase (79.24 %) in comparison with both blank (65.36 %) and negative (62.69 %) control groups; conversely, less cells were found in G2/M and S phases in the experimental group compared with controls. Moreover, anoikis was enhanced (P < 0.05), while invasion and migration abilities were reduced (P < 0.05) in TLN-1/2 knockdown cells compared with controls. TLN-1/2 knockdown inhibited MHCC-97 L cell migration (Percentage of wound healing area: experimental group: 32.6 ± 0.7 % vs. negative controls: 50.1 ± 0.6 % and blank controls: 53.6 ± 0.6 %, both P < 0.01). Finally, the tumors obtained with TLN-1/2 knockdown cells were smaller (P < 0.05) compared with controls.

Conclusion

Both TLN-1 and TLN-2 levels correlate with tumorigenicity in human HCC, indicating that these molecules constitute important molecular targets for the diagnosis and/or treatment of HCC.

Mechanisms of Invasion in Head and Neck Cancer

CONTEXT

The highly invasive properties demonstrated by head and neck squamous cell carcinoma (HNSCC) are often associated with locoregional recurrence and lymph node metastasis in patients and is a key factor leading to an expected 5-year survival rate of approximately 50% for patients with advanced disease. It is important to understand the features and mediators of HNSCC invasion so that new treatment approaches can be developed.

OBJECTIVES

To provide an overview of the characteristics, mediators, and mechanisms of HNSCC invasion.

DATA SOURCES

A literature review of peer-reviewed articles in PubMed on HNSCC invasion.

CONCLUSIONS

Histologic features of HNSCC tumors can help predict prognosis and influence clinical treatment decisions. Cell surface receptors, signaling pathways, proteases, invadopodia function, epithelial-mesenchymal transition, microRNAs, and tumor microenvironment are all involved in the regulation of the invasive behavior of HNSCC cells. Identifying effective HNSCC invasion inhibitors has the potential to improve outcomes for patients by reducing the rate of spread and increasing responsiveness to chemoradiation.

Manganese superoxide dismutase promotes interaction of actin, S100A4 and Talin, and enhances rat gastric tumor cell invasion

It has been demonstrated that cancer cells are under high levels of oxidative stress and express high levels of Manganese superoxide dismutase (MnSOD) to protect themselves and support the anabolic metabolism needed for growth and cell motility. The aim of this study was to identify proteins that may have a correlation with invasion and redox regulation by mitochondrial reactive oxygen species (ROS). MnSOD scavenges superoxide anions generated from mitochondria and is an important regulator of cellular redox status. Oxidative posttranslational modification of cysteine residues is a key mechanism that regulates protein structure and function. We hypothesized that MnSOD regulates intracellular reduced thiol status and promotes cancer invasion. A proteomic thiol-labeling approach with 5-iodoacetamidofluorescein was used to identify changes in intracellular reduced thiol-containing proteins. Our results demonstrate that overexpression of MnSOD maintained the major structural protein, actin, in a reduced state, and enhanced the invasion ability in gastric mucosal cancer cells, RGK1. We also found that the expression of Talin and S100A4 were increased in MnSOD-overexpressed RGK1 cells. Moreover, Talin bound not only with actin but also with S100A4, suggesting that the interaction of these proteins may, in part, contribute to the invasive ability of rat gastric cancer.

High expression of Talin-1 is associated with poor prognosis in patients with nasopharyngeal carcinoma

Background

Talin-1 is a cytoskeletal protein that plays an important role in tumourgenesis, migration and metastasis in several malignant tumors. The aim of this study was to evaluate the expression and prognostic value of Talin-1 in nasopharyngeal carcinoma (NPC).

Methods

Talin-1 mRNA and protein expression were examined in NPC cell lines and clinical nasopharyngeal tissues by quantitative RT-PCR, agarose gel electrophoresis and western blotting. The expression of Talin-1 was analyzed by immunohistochemical staining in 233 paraffin-embedded NPC specimens with clinical follow-up data and cox regression analysis was used to identify independent prognostic factors. The functional role of Talin-1 in NPC cell lines was evaluated by small interfering RNA-mediated depletion of the protein followed by the wound healing and transwell invasion assays.

Results

The expression of Talin-1 was significantly upregulated in most NPC cell lines and clinical tissues at both the mRNA and protein levels. High expression of Talin-1 was significantly associated with distant metastasis (P = 0.001) and patient death (P = 0.001). In addition, high expression of Talin-1 was associated with significantly poorer overall survival (OS: HR, 2.15; 95% CI, 1.28-3.63; P = 0.003) and poorer distant metastasis-free survival (DMFS: HR, 2.39; 95% CI, 1.38-4.15; P = 0.001). Cox regression analysis indicated that high expression of Talin-1 and TNM stage were independent prognostic indicators (both P < 0.05). Stratified analysis demonstrated that high expression of Talin-1 was associated with significantly poorer survival in patients with advanced stage disease (stage III-IV, HR, 1.91; 95% CI, 1.09-3.35; P = 0.02 for OS and HR, 2.22; 95% CI, 1.24-3.99; P = 0.006 for DMFS). Furthermore, the depletion of Talin-1 suppressed the migratory and invasive ability of NPC cells in vitro.

Conclusions

Our data demonstrate that high expression of Talin-1 is associated with significantly poorer OS and poorer DMFS in NPC and depletion of Talin-1 expression inhibited NPC cell migration and invasion. Talin-1 may serve as novel prognostic biomarker in NPC.

Dense fibrillar collagen is a potent inducer of invadopodia via a specific signaling network

High-density fibrillar collagen matrix induces invadopodia formation in both fibroblasts and carcinoma cell lines through a kindlin2-dependent mechanism that drives local ECM remodeling.

Cell interactions with the extracellular matrix (ECM) can regulate multiple cellular activities and the matrix itself in dynamic, bidirectional processes. One such process is local proteolytic modification of the ECM. Invadopodia of tumor cells are actin-rich proteolytic protrusions that locally degrade matrix molecules and mediate invasion. We report that a novel high-density fibrillar collagen (HDFC) matrix is a potent inducer of invadopodia, both in carcinoma cell lines and in primary human fibroblasts. In carcinoma cells, HDFC matrix induced formation of invadopodia via a specific integrin signaling pathway that did not require growth factors or even altered gene and protein expression. In contrast, phosphoproteomics identified major changes in a complex phosphosignaling network with kindlin2 serine phosphorylation as a key regulatory element. This kindlin2-dependent signal transduction network was required for efficient induction of invadopodia on dense fibrillar collagen and for local degradation of collagen. This novel phosphosignaling mechanism regulates cell surface invadopodia via kindlin2 for local proteolytic remodeling of the ECM.

Structural and mechanistic insights into the recruitment of talin by RIAM in integrin signaling

Plasma membrane (PM)-bound GTPase Rap1 recruits the Rap1-interacting-adaptor-molecule (RIAM), which in turn recruits talin to bind and activate integrins. However, it is unclear how RIAM recruits talin and why its close homolog lamellipodin does not. Here, we report that, although RIAM possesses two talin-binding sites (TBS1 and TBS2), only TBS1 is capable of recruiting cytoplasmic talin to the PM, and the R8 domain is the strongest binding site in talin. Crystal structure of an R7R8:TBS1 complex reveals an unexpected kink in the TBS1 helix that is not shared in the homologous region of lamellipodin. This kinked helix conformation is required for the colocalization of RIAM and talin at the PM and proper activation of integrin. Our findings provide the structural and mechanistic insight into talin recruitment by RIAM that underlies integrin activation and explain the differential functions of the otherwise highly homologous RIAM and lamellipodin in integrin signaling.

Recurring DNA copy number gain at chromosome 9p13 plays a role in the activation of multiple candidate oncogenes in progressing oral premalignant lesions

Genomic alteration at chromosome 9p has been previously reported as a frequent and critical event in oral premalignancy. While this alteration is typically reported as a loss driven by selection for CDKN2A deactivation (at 9p21.3), we detect a recurrent DNA copy number gain of ∼2.49 Mbp at chromosome 9p13 in oral premalignant lesions (OPLs) that later progressed to invasive lesions. This recurrent alteration event has been validated using fluorescence in situ hybridization in an independent set of OPLs. Analysis of publicly available gene expression datasets aided in identifying three oncogene candidates that may have driven selection for DNA copy number increases in this region (VCP, DCTN3, and STOML2). We performed in vitro silencing and activation experiments for each of these genes in oral cancer cell lines and found that each gene is independently capable of upregulating proliferation and anchorage-independent growth. We next analyzed the activity of each of these genes in biopsies of varying histological grades that were obtained from a diseased oral tissue field in a single patient, finding further molecular evidence of parallel activation of VCP, DCTN3, and STOML2 during progression from normal healthy tissue to invasive oral carcinoma. Our results support the conclusion that DNA gain at 9p13 is important to the earliest stages of oral tumorigenesis and that this alteration event likely contributes to the activation of multiple oncogene candidates capable of governing oral cancer phenotypes.

Integrated proteomics identified up-regulated focal adhesion-mediated proteins in human squamous cell carcinoma in an orthotopic murine model

Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules.

Talin1 phosphorylation activates β1 integrins: a novel mechanism to promote prostate cancer bone metastasis

Talins are adaptor proteins that regulate focal adhesion signaling by conjugating integrins to the cytoskeleton. Talins directly bind integrins and are essential for integrin activation. We previously showed that β1 integrins are activated in metastatic prostate cancer (PCa) cells, increasing PCa metastasis to lymph nodes and bone. However, how β1 integrins are activated in PCa cells is unknown. In this study, we identified a novel mechanism of β1 integrin activation. Using knockdown experiments, we first demonstrated talin1, but not talin2, is important in β1 integrin activation. We next showed that talin1 S425 phosphorylation, but not total talin1 expression, correlates with metastatic potential of PCa cells. Expressing a non-phosphorylatable mutant, talin1^S425A, in talin1-silenced PC3-MM2 and C4-2B4 PCa cells, decreased activation of β1 integrins, integrin-mediated adhesion, motility, and increased the sensitivity of the cells to anoikis. In contrast, re-expression of the phosphorylation-mimicking mutant talin1^S425D led to increased β1 integrin activation and generated biologic effects opposite to talin1^S425A expression. In the highly metastatic PC3-MM2 cells, expression of a non-phosphorylatable mutant, talin1^S425A, in talin1-silenced PC3-MM2 cells, abolished their ability to colonize in the bone following intracardiac injection, while re-expression of phosphorylation-mimicking mutant talin1^S425D restored their ability to metastasize to bone. Immunohistochemical staining demonstrated that talin S425 phosphorylation is significantly increased in human bone metastases when compared to normal tissues, primary tumors, or lymph node metastases. We further showed that p35 expression, an activator of Cdk5, and Cdk5 activity were increased in metastatic tumor cells, and that Cdk5 kinase activity is responsible for talin1 phosphorylation and subsequent β1 integrin activation. Together, our study reveals Cdk5-mediated phosphorylation of talin1 leading to β1 integrin activation is a novel mechanism that increases metastatic potential of PCa cells.

Genomic DNA copy number alterations from precursor oral lesions to oral squamous cell carcinoma

Oral cancer is a multifactorial disease in which both environmental and genetic factors contribute to the aetiopathogenesis. Oral cancer is the sixth most common cancer worldwide with a higher incidence among Melanesian and South Asian countries. More than 90% of oral cancers are oral squamous cell carcinoma (OSCC). The present study aimed to determine common genomic copy number alterations (CNAs) and their frequency by including 12 studies that have been conducted on OSCCs using array comparative genomic hybridization (aCGH). In addition, we reviewed the literature dealing with CNAs that drive oral precursor lesions to the invasive tumors. Results showed a sequential accumulation of genetic changes from oral precursor lesions to invasive tumors. With the disease progression, accumulation of genetic changes increases in terms of frequency, type and size of the abnormalities, even on different regions of the same chromosome. Gains in 3q (36.5%), 5p (23%), 7p (21%), 8q (47%), 11q (45%), 20q (31%) and losses in 3p (37%), 8p (18%), 9p (10%) and 18q (11%) were the most common observations among those studies. However, losses are less frequent than gains but it appears that they might be the primary clonal events in causing oral cancer.

Phosphatidylinositol phosphate 5-kinase Iγi2 in association with Src controls anchorage-independent growth of tumor cells

A fundamental property of tumor cells is to defy anoikis, cell death caused by a lack of cell-matrix interaction, and grow in an anchorage-independent manner. How tumor cells organize signaling molecules at the plasma membrane to sustain oncogenic signals in the absence of cell-matrix interactions remains poorly understood. Here, we describe a role for phosphatidylinositol 4-phosphate 5-kinase (PIPK) Iγi2 in controlling anchorage-independent growth of tumor cells in coordination with the proto-oncogene Src. PIPKIγi2 regulated Src activation downstream of growth factor receptors and integrins. PIPKIγi2 directly interacted with the C-terminal tail of Src and regulated its subcellular localization in concert with talin, a cytoskeletal protein targeted to focal adhesions. Co-expression of PIPKIγi2 and Src synergistically induced the anchorage-independent growth of nonmalignant cells. This study uncovers a novel mechanism where a phosphoinositide-synthesizing enzyme, PIPKIγi2, functions with the proto-oncogene Src, to regulate oncogenic signaling.