A cytokine signal inhibitor for rheumatoid arthritis enhances cancer metastasis via depletion of NK cells in an experimental lung metastasis mouse model of colon cancer

The role of CD56bright NK cells in neurodegenerative disorders

Emerging evidence suggests a potential role for natural killer (NK) cells in neurodegenerative diseases, such as multiple sclerosis, Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis. However, the precise function of NK cells in these diseases remains ambiguous. The existence of two NK cell subsets, CD56bright and CD56dim NK cells, complicates the understanding of the contribution of NK cells in neurodegeneration as their functions within the context of neurodegenerative diseases may differ significantly. CD56bright NK cells are potent cytokine secretors and are considered more immunoregulatory and less terminally differentiated than their mostly cytotoxic CD56dim counterparts. Hence, this review focusses on NK cells, specifically on CD56bright NK cells, and their role in neurodegenerative diseases. Moreover, it explores the mechanisms underlying their ability to enter the central nervous system. By consolidating current knowledge, we aim to provide a comprehensive overview on the role of CD56bright NK cells in neurodegenerative diseases. Elucidating their impact on neurodegeneration may have implications for future therapeutic interventions, potentially ameliorating disease pathogenesis.

JAK inhibitors and the risk of malignancy: a meta-analysis across disease indications

OBJECTIVES

To estimate the association of Janus kinase inhibitors (JAKi) with the incidence of malignancy, compared with placebo, tumour necrosis factor (TNF)-α inhibitors (TNFi) and methotrexate.

METHODS

Systematic searches of databases were performed, to December 2022, to identify phase II/III/IV randomised clinical trials (RCTs) and long-term extension (LTE) studies of JAKi (tofacitinib, baricitinib, upadacitinib, filgotinib, peficitinib) compared with placebo, TNFi or methotrexate, in adults with rheumatoid arthritis, psoriatic arthritis, psoriasis, axial spondyloarthritis, inflammatory bowel disease or atopic dermatitis. Network and pairwise meta-analyses were performed to estimate incidence rate ratios (IRRs) for malignancy between JAKi and comparators. Bias was assessed using the Cochrane Risk of Bias-2 tool.

RESULTS

In 62 eligible RCTs and 16 LTE studies, there were 82 366 person-years of exposure to JAKi, 2924 to placebo, 7909 to TNFi and 1074 to methotrexate. The overall malignancy incidence rate was 1.15 per 100 person-years in RCTs, and 1.26 per 100 person-years across combined RCT and LTE data. In network meta-analyses, the incidence of all malignancies including non-melanomatous skin cancers (NMSCs) was not significantly different between JAKi and placebo (IRR 0.71; 95% CI 0.44 to 1.15) or between JAKi and methotrexate (IRR 0.77; 95% CI 0.35 to 1.68). Compared with TNFi, however, JAKi were associated with an increased incidence of malignancy (IRR 1.50; 95% CI 1.16 to 1.94). Findings were consistent when analysing NMSC only and when analysing combined RCT/LTE data.

CONCLUSIONS

JAKi were associated with a higher incidence of malignancy compared with TNFi but not placebo or methotrexate. Cancers were rare events in all comparisons.

PROSPERO REGISTRATION NUMBER

CRD42022362630.

Screening and validation of platelet activation-related lncRNAs as potential biomarkers for prognosis and immunotherapy in gastric cancer patients

Background: Platelets (PLT) have a significant effect in promoting cancer progression and hematogenous metastasis. However, the effect of platelet activation-related lncRNAs (PLT-related lncRNAs) in gastric cancer (GC) is still poorly understood. In this study, we screened and validated PLT-related lncRNAs as potential biomarkers for prognosis and immunotherapy in GC patients.

Methods: We obtained relevant datasets from the Cancer Genome Atlas (TCGA) and Gene Ontology (GO) Resource Database. Pearson correlation analysis was used to identify PLT-related lncRNAs. By using the univariate, least absolute shrinkage and selection operator (LASSO) Cox regression analyses, we constructed the PLT-related lncRNAs model. Kaplan-Meier survival analysis, univariate, multivariate Cox regression analysis, and nomogram were used to verify the model. The Gene Set Enrichment Analysis (GSEA), drug screening, tumor immune microenvironment analysis, epithelial-mesenchymal transition (EMT), and DNA methylation regulators correlation analysis were performed in the high- and low-risk groups. Patients were regrouped based on the risk model, and candidate compounds and immunotherapeutic responses aimed at GC subgroups were also identified. The expression of seven PLT-related lncRNAs was validated in clinical medical samples using quantitative reverse transcription-polymerase chain reaction (qRT-PCR).

Results: In this study, a risk prediction model was established using seven PLT-related lncRNAs -(AL355574.1, LINC01697, AC002401.4, AC129507.1, AL513123.1, LINC01094, and AL356417.2), whose expression were validated in GC patients. Kaplan-Meier survival analysis, the receiver operating characteristic (ROC) curve analysis, univariate, multivariate Cox regression analysis verified the accuracy of the model. We screened multiple targeted drugs for the high-risk patients. Patients in the high-risk group had a poorer prognosis since low infiltration of immune killer cells, activation of immunosuppressive pathways, and poor response to immunotherapy. In addition, we revealed a close relationship between risk scores and EMT and DNA methylation regulators. The nomogram based on risk score suggested a good ability to predict prognosis and high clinical benefits.

Conclusion: Our findings provide new insights into how PLT-related lncRNAs biomarkers affect prognosis and immunotherapy. Also, these lncRNAs may become potential biomarkers and therapeutic targets for GC patients.

Emerging roles of platelets in cancer biology and their potential as therapeutic targets

The main role of platelets is to control bleeding and repair vascular damage via thrombosis. They have also been implicated to promote tumor metastasis through platelet-tumor cell interactions. Platelet-tumor cell interactions promote tumor cell survival and dissemination in blood circulation. Tumor cells are known to induce platelet activation and alter platelet RNA profiles. Liquid biopsies based on tumor-educated platelet biomarkers can detect tumors and correlate with prognosis, personalized therapy, treatment monitoring, and recurrence prediction. Platelet-based strategies for cancer prevention and tumor-targeted therapy include developing drugs that target platelet receptors, interfere with the release of platelet particles, inhibit platelet-specific enzymes, and utilize platelet-derived “nano-platelets” as a targeted drug delivery platform for tumor therapy. This review elaborates on platelet-tumor cell interactions and the molecular mechanisms and discusses future research directions for platelet-based liquid biopsy techniques and platelet-targeted anti-tumor strategies.

Long non-coding RNA LBX2-AS1 predicts poor survival of colon cancer patients and promotes its progression via regulating miR-627-5p/RAC1/PI3K/AKT pathway

Colon cancer is one of the most prevalent malignant tumors across the world. Increasing studies have demonstrated that long non-coding RNAs (lncRNAs) take part in colon cancer development. Our study intends to explore the expression characteristics of LBX2-AS1, a novel lncRNA, in colon cancer and its underlying mechanisms. The results illustrated that LBX2-AS1 level was substantially increased in colon cancer tissues and was obviously correlated with the tumor volume and early distant metastasis of patients. Besides, overexpression of LBX2-AS1 remarkably boosted growth, proliferation, and metastasis and restrained apoptosis in colon cancer cells, whereas LBX2-AS1 knockdown produced the opposite effect. On the other hand, miR-627-5p, down-regulated in colon cancer tissues, was negatively associated with LBX2-AS1 expression. Functional experiments showed that miR-627-5p suppressed colon cancer growth. Mechanistically, LBX2-AS1, as an endogenous competitive RNA, targeted miR-627-5p and restrained its expression, while miR-627-5p targeted and negatively regulated the RAC1/PI3K/AKT axis. Collectively, this study has revealed that LBX2-AS1 is a poor prognostic factor of colon cancer and can regulate colon cancer progression by regulating the miR-627-5p/RAC1/PI3K/AKT pathway.

Tofacitinib Suppresses Natural Killer Cells In Vitro and In Vivo: Implications for Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal and incurable neurodegenerative disease with few therapeutic options. However, the immune system, including natural killer (NK) cells, is linked to ALS progression and may constitute a viable therapeutic ALS target. Tofacitinib is an FDA-approved immunomodulating small molecule which suppresses immune cell function by blocking proinflammatory cytokine signaling. This includes the cytokine IL-15 which is the primary cytokine associated with NK cell function and proliferation. However, the impact of tofacitinib on NK activation and cytotoxicity has not been thoroughly investigated, particularly in ALS. We therefore tested the ability of tofacitinib to suppress cytotoxicity and cytokine production in an NK cell line and in primary NK cells derived from control and ALS participants. We also investigated whether tofacitinib protected ALS neurons from NK cell cytotoxicity. Finally, we conducted a comprehensive pharmacokinetic study of tofacitinib in mice and tested the feasibility of administration formulated in chow. Success was assessed through the impact of tofacitinib on peripheral NK cell levels in mice. We found tofacitinib suppressed IL-15-induced activation as measured by STAT1 phosphorylation, cytotoxicity, pro-inflammatory gene expression, and pro-inflammatory cytokine secretion in both an NK cell line and primary NK cells. Furthermore, tofacitinib protected ALS neurons from NK cell-mediated cytotoxicity. In mice, we found tofacitinib bioavailability was 37% in both male and female mice; using these data we formulated mouse containing low and high doses of tofacitinib and found that the drug suppressed peripheral NK cell levels in a dose-dependent manner. These results demonstrate that tofacitinib can suppress NK cell function and may be a viable therapeutic strategy for ALS.

Gene therapy with SOCS1 induces potent preclinical antitumor activities in oral squamous cell carcinoma

BACKGROUND

Constitutive activation of STAT3 promotes oncogenesis and growth of oral squamous cell carcinoma (OSCC). We investigated the mechanism of action of suppressor of cytokine signaling 1 (SOCS1), an endogenous inhibitor of JAK, as gene therapy for OSCC.

METHODS

Antitumor effect of SOCS1 was compared to JAK inhibitor I by cell proliferation assay, cell cycle analysis, and apoptosis analysis in vitro. In addition, antitumor effect was evaluated using xenograft mouse models in vivo.

RESULTS

JAK inhibitor I inhibited the proliferation of KOSC2 cl3-43 or T3M-1 clone2 OSCC cell lines in vitro. While JAK inhibitor I arrested both cell lines at the G2/M phase, induction of apoptosis was observed in T3M-1 clone2 cells, but not KOSC2-cl3-43 cells. An adenoviral vector expressing SOCS1 (AdSOCS1) significantly decreased the proliferation of both OSCC cell lines and induced G2/M phase cell cycle arrest and apoptosis, suggesting that induction of apoptosis of KOSC2 cl3-43 cells by AdSOCS1 is regulated by the JAK/STAT independent pathway. Overexpression of SOCS1 inhibited activation of the JAK/STAT and p44/42 MAPK pathways, while JAK inhibitor I inhibited activation of the JAK/STAT pathway only. Consistently, expression of Mcl-1 was decreased by overexpression of SOCS1, but not JAK inhibitor I. Additionally, KOSC2 cl3-43 or T3M-1 clone2 OSCC cells were subcutaneously implanted in the flanks of two xenograft mouse models. As compared to a control adenovirus vector (AdLacZ), intratumor injection of AdSOCS1 significantly decreased the tumor volume and induced apoptosis in vivo.

CONCLUSION

SOCS1 gene therapy may be a beneficial approach for the treatment of OSCC.

Bidirectional Interaction Between Cancer Cells and Platelets Provides Potential Strategies for Cancer Therapies

Platelets are essential components in the tumor microenvironment. For decades, clinical data have demonstrated that cancer patients have a high risk of thrombosis that is associated with adverse prognosis and decreased survival, indicating the involvement of platelets in cancer progression. Increasing evidence confirms that cancer cells are able to induce production and activation of platelets. Once activated, platelets serve as allies of cancer cells in tumor growth and metastasis. They can protect circulating tumor cells (CTCs) against the immune system and detachment-induced apoptosis while facilitating angiogenesis and tumor cell adhesion and invasion. Therefore, antiplatelet agents and platelet-based therapies should be developed for cancer treatment. Here, we discuss the mechanisms underlying the bidirectional cancer-platelet crosstalk and platelet-based therapeutic approaches.

Evaluating filgotinib for the treatment of rheumatoid arthritis

INTRODUCTION

Despite the availability of an extensive armamentarium, rheumatoid arthritis (RA) remains a therapeutic challenge for rheumatologists. Janus kinase inhibitors (JAKi) are an emerging class of targeted therapies. The number of JAKi has been growing and to date, filgotinib is the latest JAKi to be approved for use in RA.

AREAS COVERED

This review focuses on the pharmacodynamics, pharmacokinetics, efficacy and safety of filgotinib in patients with RA.

EXPERT OPINION

Filgotinib is an oral targeted synthetic disease-modifying antirheumatic drug (DMARD) that specifically inhibits JAKi. Filgotinib monotherapy, or a combination regimen with conventional synthetic (cs) DMARDs, has demonstrated efficacy in decreasing disease activity, with a well-managed safety profile in patients with early RA naive to DMARDs, and in RA that does not adequately respond to csDMARDs and/or biologic DMARDs. The selective inhibition of JAK1 may confer an improved safety profile, but further study is required as a potential testicular toxicity has been suggested. Filgotinib offers several advantages: oral administration, rapidity of action, efficacy as monotherapy, and demonstrated activity in difficult to treat RA. However, the placement of filgotinib in the therapeutic arsenal for RA may be influenced by the ongoing collection of long-term safety data from JAKi as a class.

Immunomodulatory Effect of Lactobacillus casei in a Murine Model of Colon Carcinogenesis

We previously reported beneficial effects of the probiotic strain Lactobacillus casei 393 in hindering colon carcinogenesis in a 1,2-dimethylhydrazine (DMH)-induced BALB/c mouse model of colon cancer. In the present study, we investigated the effect of preventive administration of L. casei 393 on the levels of selected pro- and anti-inflammatory circulating cytokines, as well as subpopulations of splenic T cells. The resulting experimental data on IFNγ, TNFα, IL-10, and colon histological features demonstrated that administration of L. casei 2 weeks before DMH treatment impaired the pro-inflammatory effect of DMH, while maintaining the levels of the three cytokines as well as colon histology; it also modulated splenic CD4⁺, CD8⁺, and NK T cell subpopulations. The preventive administration of L. casei to DMH-treated mice increased IL-17A synthesis and Treg percentages, further indicating a tumor-protecting role. Together, the results suggest that the colon-cancer-protective properties of L. casei 393 involve the dampening of inflammation through cytokine homeostasis and the maintenance of a healthy T cell subpopulation dynamic. For these reasons, probiotics such as L. casei may contribute to the health of the host as they promote optimal control of the immune response. Further, they may be used as prophylactic agents in combination with standard therapies against colon cancer.

Not Only Immune Escape-The Confusing Role of the TRP Metabolic Pathway in Carcinogenesis

BACKGROUND

The recently discovered phenomenon that cancer cells can avoid immune response has gained scientists' interest. One of the pathways involved in this process is tryptophan (TRP) metabolism through the kynurenine pathway (KP). Individual components involved in TRP conversion seem to contribute to cancerogenesis both through a direct impact on cancer cells and the modulation of immune cell functionality. Due to this fact, this pathway may serve as a target for immunotherapy and attempts are being made to create novel compounds effective in cancer treatment. However, the results obtained from clinical trials are not satisfactory, which raises questions about the exact role of KP elements in tumorigenesis. An increasing number of experiments reveal that TRP metabolites may either be tumor promoters and suppressors and this is why further research in this field is highly needed. The aim of this study is to present KP as a modulator of cancer development through multiple mechanisms and to point to its ambiguity, which may be a reason for failures in treatment based on the inhibition of tryptophan metabolism.

Untwining Anti-Tumor and Immunosuppressive Effects of JAK Inhibitors-A Strategy for Hematological Malignancies?

Simple Summary

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway is aberrantly activated in many malignancies. Inhibition of this pathway via JAK inhibitors (JAKinibs) is therefore an attractive therapeutic strategy underlined by Ruxolitinib (JAK1/2 inhibitor) being approved for the treatment of myeloproliferative neoplasms. As a consequence of the crucial role of the JAK-STAT pathway in the regulation of immune responses, inhibition of JAKs suppresses the immune system. This review article provides a thorough overview of the current knowledge on JAKinibs’ effects on immune cells in the context of hematological malignancies. We also discuss the potential use of JAKinibs for the treatment of diseases in which lymphocytes are the source of the malignancy.

Abstract

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway propagates signals from a variety of cytokines, contributing to cellular responses in health and disease. Gain of function mutations in JAKs or STATs are associated with malignancies, with JAK2^V617F being the main driver mutation in myeloproliferative neoplasms (MPN). Therefore, inhibition of this pathway is an attractive therapeutic strategy for different types of cancer. Numerous JAK inhibitors (JAKinibs) have entered clinical trials, including the JAK1/2 inhibitor Ruxolitinib approved for the treatment of MPN. Importantly, loss of function mutations in JAK-STAT members are a cause of immune suppression or deficiencies. MPN patients undergoing Ruxolitinib treatment are more susceptible to infections and secondary malignancies. This highlights the suppressive effects of JAKinibs on immune responses, which renders them successful in the treatment of autoimmune diseases but potentially detrimental for cancer patients. Here, we review the current knowledge on the effects of JAKinibs on immune cells in the context of hematological malignancies. Furthermore, we discuss the potential use of JAKinibs for the treatment of diseases in which lymphocytes are the source of malignancies. In summary, this review underlines the necessity of a robust immune profiling to provide the best benefit for JAKinib-treated patients.

Signal transducer and activator of transcription 6 as a target in colon cancer therapy

Signal transducer and activator of transcription 6 (STAT6) is a member of the STAT family of proteins that serve key roles in the initiation of tumorigenesis and malignant transformation. STAT6 is highly expressed in several types of cancer, including breast, pancreatic, prostate and colorectal cancer. STAT6 transduces signals in response to the binding of interleukin (IL)-4 and IL-13 to their receptors and regulates the expression of genes involved in the immune response, cell survival, tumor proliferation and metastasis. Patients with colorectal cancer exhibit high STAT6 activity in the colonic epithelium, and STAT6 expression is associated with lower survival rates, lymph node metastasis, changes in the epithelial barrier function and alterations in the inflammatory response. A number of studies investigating experimental models and cancer cell lines have revealed that STAT6 is associated with tumor growth and development, as well as with increased invasion and metastasis, suggesting that STAT6 inhibition may serve as a novel therapeutic strategy in colon cancer. The present review summarizes the evidence with regard to the implications of STAT6 in cancer biology and the direct and indirect effects on colon tumor transformation. Furthermore, the current treatment strategies targeting the IL-4/IL-13/STAT6 axis in colon cancer are discussed.

Growing evidence of the safety of JAK inhibitors in patients with rheumatoid arthritis

To facitinib and baricitinib are two of the currently available Janus kinase (JAK) inhibitors for the treatment of patients with RA. Randomized controlled trials have shown that these JAK inhibitors are as efficacious as biological DMARDs. Safety profiles of these JAK inhibitors in randomized controlled trials and their long-term extension studies have been demonstrated; however, real world evidence remains to be established to bridge the gap between randomized controlled trials and rheumatology clinics. Fundamentally, no difference in the screening, prevention, and monitoring of infections between JAK inhibitors and biological DMARDs exists. However, increased risk of herpes zoster is probably common to all JAK inhibitors. No indication of increased risk for malignancy in patients with RA treated with JAK inhibitors has been reported. To evaluate risks of relatively rare serious adverse events such as thromboembolic events, gastrointestinal perforation, and interstitial lung disease in clinical settings, accumulation of cases with these events are needed. Continuous pharmacovigilance activity is absolutely warranted to establish the safety of JAK inhibitors in patients with RA and other rheumatic diseases.

Resveratrol inhibits the invasion and metastasis of colon cancer through reversal of epithelial‑ mesenchymal transition via the AKT/GSK‑3β/Snail signaling pathway

The identification of safe and effective drugs that inhibit tumor invasion and metastasis is required to improve the clinical outcome of patients with colon cancer. The present study aimed to investigate the inhibitory effects and possible mechanisms of action of resveratrol against the invasion and metastasis of colon cancer. AKT1-knockdown SW480 and SW620 colon cancer cells were used to detect the effects of resveratrol on cell invasion and metastasis, as well as changes in the expression of epithelial-mesenchymal transition (EMT) markers and serine/threonine kinase (AKT)/glycogen synthase kinase (GSK)-3β/Snail signaling pathway-related molecules in vitro. Furthermore, nude mice were inoculated with SW480 cells in the tail vein to establish an in vivo lung metastasis model of colon cancer, to investigate the effects of resveratrol on lung metastasis in colon cancer. The results revealed that resveratrol treatment and AKT1 knockdown significantly inhibited cell migration and invasion in colon cancer, and markedly increased E-cadherin expression and decreased that of N-cadherin, phospho (p)-AKT1, p-GSK-3β, and Snail in colon cancer both in vitro and in vivo. Furthermore, the effects of resveratrol were significantly weaker in the AKT1-knockdown cells. In conclusion, resveratrol may suppress the invasion and metastasis of colon cancer through reversal of EMT via the AKT/GSK-3β/Snail signaling pathway. AKT1 may therefore be a key regulator of EMT in colon cancer cells and a potential therapeutic target for this disease.

Tofacitinib for the treatment of rheumatoid arthritis: an update

INTRODUCTION

Tofacitinib inhibits the Janus kinases, tyrosine kinases that are activated by cytokines involved in the pathophysiology of rheumatoid arthritis. Areas covered: Clinical trials have revealed an anti-rheumatic effect of monotherapy and combination therapy with methotrexate (MTX). Post-hoc analysis of those clinical trials and real-world experiences will be reviewed to explore efficacy and safety. Expert commentary: The efficacy of tofacitinib monotherapy has garnered much attention and has been initiated in large number of patients. However, combination therapy with MTX is necessary in order to achieve the maximum effect. Combination therapy can be transferred to monotherapy by tapering and/or discontinuing MTX. The discontinuation of tofacitinib should be avoided and tapering should be investigated. There has been no new safety signal although venous thrombotic events (VTEs) have been raised and would require long-term follow-up. Increased events of Herpes zoster were observed and the use of a subunit vaccination is expected to become an effective tool for prevention. Post-hoc analysis of the clinical trials and real-world experience is revealing further usefulness of tofacitinib not only in rheumatoid arthritis but also other diseases. Additional experience and data from the real world are required to help improve the use of tofacitinib..

RasGRF2 promotes migration and invasion of colorectal cancer cells by modulating expression of MMP9 through Src/Akt/NF-κB pathway

Ras-specific guanine nucleotide-releasing factor 2 (RasGRF2) is a member of the guanine nucleotide exchange factors family which is expressed in a variety of tissues and cancer. However, the role of RasGRF2 in cancer is less reported, especially in colorectal cancer(CRC). Hence, the present study aimed to investigated the function of RasGRF2 and ways in which it affects tumor progression in CRC samples and cell lines. We first measured RasGRF2 mRNA level in 26 paired tumor and nontumor colon tissues after colon cancer surgical resection, and determined RasGRF2 protein level in 97 paired paraffin-embedded colon cancer tissues, and found that levels of RasGRF2 mRNA and protein were increased in colorectal tumor tissues, compared with adjacent non-tumor tissues. We then examined the effects of RasGRF2 knockdown on proliferation, migration and invasion were analyzed in CRC cells (SW480, HCT116 and LS174T). HCT116 cells with RasGRF2 knockdown were injected into the tail vein in nude mice to yield metastatic model, and tumor metastasis was measured as well. We found that knockdown of RasGRF2 in CRC cells reduced their migration and invasion in vitro and metastasis in mice. Furthermore, we explored the underlying molecular mechanism for RasGRF2-mediated CRC migration and invasion. The results showed that knockdown of RasGRF2 in CRC cells impairing the expression of MMP9 and inhibiting the activation of Src/Akt and NF-κB signaling. We conclude that RasGRF2 plays a role in controlling migration and invasion of CRC and modulates the expression of MMP9 through Src/PI 3-kinase and the NF-κB pathways.

Cellular senescence: a view throughout organismal life

Cellular senescence is the final fate of most cells in response to specific stimuli, but is not the end. Indeed, it is the beginning of a singular life, with multiple side roads leading to diverse effects on the organism. Many studies have been done in the last few years to elucidate the intriguing role of senescent cells in the organism, demonstrating them as the cause of several age-related diseases. However, these cells are also positively implicated in other important pathways, such as embryogenesis and wound healing. It appears that the multiple effects are time-dependent: long-term senescence is mostly implicated in chronic inflammation and disease, whereas in the short term, senescent cells seem to be beneficial, being rapidly targeted by the innate immune system. The influence of senescent cells on their neighbors by paracrine factors, differential activity depending on developmental stage, and duration of the effects make the cellular senescent program a unique spatial-temporal mechanism. During pathological conditions such as progeroid syndromes, this mechanism is deregulated, leading to accelerated onset of some aging-related diseases and a shorter lifespan, among other physiological defects. Here, we review the three primary cell senescence programs described so far (replicative, stress-induced, and developmentally programmed senescence), their onset during development, and their potential roles in diseases with premature aging. Finally, we discuss the role of immune cells in keeping senescence burden below the threshold of disease.

Human Cancer and Platelet Interaction, a Potential Therapeutic Target

Cancer patients experience a four-fold increase in thrombosis risk, indicating that cancer development and progression are associated with platelet activation. Xenograft experiments and transgenic mouse models further demonstrate that platelet activation and platelet-cancer cell interaction are crucial for cancer metastasis. Direct or indirect interaction of platelets induces cancer cell plasticity and enhances survival and extravasation of circulating cancer cells during dissemination. In vivo and in vitro experiments also demonstrate that cancer cells induce platelet aggregation, suggesting that platelet-cancer interaction is bidirectional. Therefore, understanding how platelets crosstalk with cancer cells may identify potential strategies to inhibit cancer metastasis and to reduce cancer-related thrombosis. Here, we discuss the potential function of platelets in regulating cancer progression and summarize the factors and signaling pathways that mediate the cancer cell-platelet interaction.

Therapeutic effects of tyroserleutide on lung metastasis of human hepatocellular carcinoma SK-HEP-1 and its mechanism affecting ICAM-1 and MMP-2 and -9

BACKGROUND

Tyroserleutide (YSL) inhibits the growth and metastasis of human hepatocellular carcinoma (HCC). This paper studied the effect of YSL on metastasis of human HCC and investigated its mechanisms.

METHODS

In vivo, experimental lung metastasis models of human HCC SK-HEP-1 cells in nude mice were established, and In vitro, the proliferation, adhesion and invasion of SK-HEP-1 cells were detected.

RESULTS

In vivo, YSL significantly inhibited the metastasis of human HCC. In vitro, YSL significantly inhibited the proliferation, adhesion and invasion of SK-HEP-1 cells. Through analyses with reverse transcription PCR (RT-PCR) and Western blot, we observed that YSL significantly inhibited the expressions of ICAM-1 in SK-HEP-1 cells. Through RT-PCR, Western blot and zymography methods, YSL was discovered to decrease the mRNA level, protein expression and activity of MMP-2 and -9 in SK-HEP-1 cells.

CONCLUSION

We concluded that YSL could inhibit tumor growth and metastasis of human HCC SK-HEP-1 cells.