Roles of thymosins in cancers and other organ systems

Therapeutic applications of thymosin peptides: a patent landscape 2018-present

INTRODUCTION

Thymosins are small proteins found mainly in the thymus. They are involved in several biological processes, including immunoregulation, angiogenesis, and anti-inflammatory activity. Due to these multiple activities, thymosins are widely used as therapeutics. In fact, these peptides have shown interesting results in the treatment of eye disorders, anticancer therapy, and dysregulated immune disorders.

AREA COVERED

We analyzed the thymosins therapeutic patent landscape describing the most significant patents published after 2018 and originally written in English, classified according to the different type of functions and diseases. We searched 'Thymosin' on Patentscope and Espacenet.

EXPERT OPINION

Thymalfasin (Zadaxin) is the only FDA-approved thymosine-based drug used to treat chronic hepatitis B and C and as a chemotherapy inducer. This outcome demonstrates how thymosins can be exploited as therapeutics, especially in immunological and anti-cancer therapies. However, the development of modified thymosins could expand their therapeutic interest and application in different diseases. In fact, by chemical modifications, it is possible to increase proteolytic stability in the biological environment, enhance cell permeability, and stabilize the secondary structure of the peptide. Finally, the development of shorter sequences could reduce the cost and production time of these thymosin-based drugs.

Whole-Exome sequencing analysis identified TMSB10/TRABD2A locus to be associated with carfilzomib-related cardiotoxicity among patients with multiple myeloma

Background

Proteasome inhibitor Carfilzomib (CFZ) is effective in treating patients with refractory or relapsed multiple myeloma (MM) but has been associated with cardiovascular adverse events (CVAE) such as hypertension, cardiomyopathy, and heart failure. This study aimed to investigate the contribution of germline genetic variants in protein-coding genes in CFZ-CVAE among MM patients using whole-exome sequencing (WES) analysis.

Methods

Exome-wide single-variant association analysis, gene-based analysis, and rare variant analyses were performed on 603,920 variants in 247 patients with MM who have been treated with CFZ and enrolled in the Oncology Research Information Exchange Network (ORIEN) at the Moffitt Cancer Center. Separate analyses were performed in European Americans and African Americans followed by a trans-ethnic meta-analysis.

Results

The most significant variant in the exome-wide single variant analysis was a missense variant rs7148 in the thymosin beta-10/TraB Domain Containing 2A (TMSB10/TRABD2A) locus. The effect allele of rs7148 was associated with a higher risk of CVAE [odds ratio (OR) = 9.3 with a 95% confidence interval of 3.9-22.3, p = 5.42*10^-7]. MM patients with rs7148 AG or AA genotype had a higher risk of CVAE (50%) than those with GG genotype (10%). rs7148 is an expression quantitative trait locus (eQTL) for TRABD2A and TMSB10. The gene-based analysis also showed TRABD2A as the most significant gene associated with CFZ-CVAE (p = 1.06*10^-6).

Conclusions

We identified a missense SNP rs7148 in the TMSB10/TRABD2A as associated with CFZ-CVAE in MM patients. More investigation is needed to understand the underlying mechanisms of these associations.

Pancancer landscape analysis of the thymosin family identified TMSB10 as a potential prognostic biomarker and immunotherapy target in glioma

Background

Thymosin family genes (TMSs), biologically important peptides with diverse intracellular and extracellular functions, have been shown to promote the progression of multiple cancers. However, multiomics characterization of TMSs and their role in human cancer prognosis has not been systematically performed.

Methods

We performed a comprehensive analysis of TMSs and thymosin β10 (TMSB10) using multiomics data from more than 10,000 tumor samples of 33 cancer types from The Cancer Genome Atlas (TCGA). We used single-sample gene set enrichment analysis (ssGSEA) and the gene set variation analysis (GSVA) algorithm to investigate the differences in tumor microenvironment (TME) cell infiltration and functional annotation for individual tumor samples, respectively. The role of TMSB10 in the malignant progression of glioma, the promotion of macrophage infiltration,and immunosuppressive polarization, and the combination drug efficacy were assessed via biological function assays.

Results

We comprehensively assessed genomic mutations, expression dysregulation, prognosis and immunotherapeutic response across 33 human cancer samples and showed that TMSB10 is specifically overexpressed in almost all types of cancer tissues. Further pan-cancer analysis showed that TMSB10 is closely related to the biological function, immune regulation and prognosis of glioma. Similar results were also found in several public glioma cohorts and our Qilu local cohort. Further integration with other biological experiments revealed the key roles of TMSB10 in the malignant progression of glioma, the promotion of macrophage infiltration and immunosuppressive polarization. We also identified multiple drugs targeting cells with high TMSB10 expression and validated that knockdown of TMSB10 improved the efficacy of selumetinib (a MEK1/2 inhibitor approved by the FDA for the treatment of neurofibromatosis-associated tumors) and anti-PD1 treatment in glioma.

Conclusion

These results indicate that TMSB10 holds promise as a novel prognostic marker and therapeutic target, providing a theoretical basis for the development of more effective and targeted clinical treatment strategies for glioma patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02698-5.

Pediatric Brain Tumors: Signatures from the Intact Proteome

The present investigation aimed to explore the intact proteome of tissues of pediatric brain tumors of different WHO grades and localizations, including medulloblastoma, pilocytic astrocytoma, and glioblastoma, in comparison with the available data on ependymoma, to contribute to the understanding of the molecular mechanisms underlying the onset and progression of these pathologies. Tissues have been homogenized in acidic water−acetonitrile solutions containing proteases inhibitors and analyzed by LC−high resolution MS for proteomic characterization and label-free relative quantitation. Tandem MS spectra have been analyzed by either manual inspection or software elaboration, followed by experimental/theoretical MS fragmentation data comparison by bioinformatic tools. Statistically significant differences in protein/peptide levels between the different tumor histotypes have been evaluated by ANOVA test and Tukey’s post-hoc test, considering a p-value > 0.05 as significant. Together with intact protein and peptide chains, in the range of molecular mass of 1.3−22.8 kDa, several naturally occurring fragments from major proteins, peptides, and proteoforms have been also identified, some exhibiting proper biological activities. Protein and peptide sequencing allowed for the identification of different post-translational modifications, with acetylations, oxidations, citrullinations, deamidations, and C-terminal truncations being the most frequently characterized. C-terminal truncations, lacking from two to four amino acid residues, particularly characterizing the β-thymosin peptides and ubiquitin, showed a different modulation in the diverse tumors studied. With respect to the other tumors, medulloblastoma, the most frequent malignant brain tumor of the pediatric age, was characterized by higher levels of thymosin β4 and β10 peptides, the latter and its des-IS form particularly marking this histotype. The distribution pattern of the C-terminal truncated forms was also different in glioblastoma, particularly underlying gender differences, according to the definition of male and female glioblastoma as biologically distinct diseases. Glioblastoma was also distinguished for the peculiar identification of the truncated form of the α-hemoglobin chain, lacking the C-terminal arginine, and exhibiting oxygen-binding and vasoconstrictive properties different from the intact form. The proteomic characterization of the undigested proteome, following the top-down approach, was challenging to originally investigate the post-translational events that differently characterize pediatric brain tumors. This study provides a contribution to elucidate the molecular profiles of the solid tumors most frequently affecting the pediatric age, and which are characterized by different grades of aggressiveness and localization.

TMSB10, a potential prognosis prediction biomarker, promotes the invasion and angiogenesis of gastric cancer

BACKGROUND AND AIM

The thymosin beta 10 (TMSB10) was originally identified from the thymus, which plays a key role in the development of many cancers. However, the underlying molecular mechanisms of TMSB10 involved in GC have not been understood.

METHODS

We sought to determine the expression of TMSB10 in human GC tissues and illustrate whether it is correlated with the clinical pathologic characteristics and prognosis in GC patients. Its roles and potential mechanisms in regulating tumor growth, invasion, and angiogenesis were evaluated by TMSB10 knockdown/overexpression of GC cells in vitro and ex vivo.

RESULTS

Marked overexpression of TMSB10 protein expression was observed in GC cells and tissues, which was associated with the advanced tumor stage and lymph nodes (LN) metastasis of GC patients. Furthermore, prognostic analysis showed that GC patients with high TMSB10 expression had a remarkably shorter survival and acted as an important factor for predicting poor overall survival in GC patients. Moreover, TMSB10 overexpression promoted, while TMSB10 knockdown the proliferation, EMT process, and angiogenesis of GC cells.

CONCLUSION

The study highlights that TMSB10 may hold promise as potential prognosis prediction biomarker for the diagnosis of GC and a potential therapeutic target, which will facilitate the development of a novel therapeutic strategy against GC.

Changes in Biomechanical Properties of A375 Cells Due to the Silencing of TMSB4X Expression Are Not Directly Correlated with Alterations in Their Stemness Features

Thymosin β4 (Tβ4) is a small, 44-amino acid polypeptide. It has been implicated in multiple processes, including cell movement, angiogenesis, and stemness. Previously, we reported that melanoma cell lines differ in Tβ4 levels. Studies on stable clones with silenced TMSB4X expression showed that Tβ4 impacted adhesion and epithelial-mesenchymal transition progression. Here, we show that the cells with silenced TMSB4X expression exhibited altered actin cytoskeleton’s organization and subcellular relocalization of two intermediate filament proteins: Nestin and Vimentin. The rearrangement of the cell cytoskeleton resulted in changes in the cells’ topology, height, and stiffness defined by Young’s modulus. Simultaneously, only for some A375 clones with a lowered Tβ4 level, we observed a decreased ability to initiate colony formation in soft agar, tumor formation in vivo, and alterations in Nanog’s expression level transcription factor regulating stemness. Thus, we show for the first time that in A375 cells, biomechanical properties are not directly coupled to stemness features, and this cell line is phenotypically heterogeneous.

Adamantinomatous craniopharyngioma: advances in proteomic research

BACKGROUND

Many efforts have been performed in the last decade to accomplish the genomic and proteomic characterization of pediatric adamantinomatous craniopharyngioma with the purpose to elucidate the molecular mechanisms underlying the onset and development of this pediatric brain tumor, its high recurrence rate, and, although classified as a histologically benign neoplasm, its aggressive behavior.

METHODS

The focus of this review is to perform the new comparison of the proteomic profiles of the solid component and the intracystic fluid of adamantinomatous craniopharyngioma based on our previous results, obtained by both the top-down and the bottom-up proteomic approaches, to disclose differences and similarities, and to discuss the results in the context of the most recent literature.

RESULTS AND CONCLUSIONS

Proteins and peptides identified in the cyst fluid and in the solid component of adamantinomatous craniopharyngioma (AC) include beyond markers of inflammation (i.e., alpha-defensins), proteins involved in cell migration and protein degradation (i.e., beta-thymosin and ubiquitin peptides), whose main role might be in tumor growth and infiltration of the surrounding neural structures. These last appeared different in the solid components compared with the cyst fluid, missing their terminal part in the solid tissue, a feature generally associated to malignancies, which might represent a distinct molecular site for an aggressive behavior of AC.

Thymus-Pineal Gland Axis: Revisiting Its Role in Human Life and Ageing

For years the thymus gland (TG) and the pineal gland (PG) have been subject of increasingly in-depth studies, but only recently a link that can associate the activities of the two organs has been identified. Considering, on the one hand, the well-known immune activity of thymus and, on the other, the increasingly emerging immunological roles of circadian oscillators and the rhythmically secreted main pineal product, melatonin, many studies aimed to analyse the possible existence of an interaction between these two systems. Moreover, data confirmed that the immune system is functionally associated with the nervous and endocrine systems determining an integrated dynamic network. In addition, recent researches showed a similar, characteristic involution process both in TG and PG. Since the second half of the 20th century, evidence led to the definition of an effectively interacting thymus-pineal axis (TG-PG axis), but much has to be done. In this sense, the aim of this review is to summarize what is actually known about this topic, focusing on the impact of the TG-PG axis on human life and ageing. We would like to give more emphasis to the implications of this dynamical interaction in a possible therapeutic strategy for human health. Moreover, we focused on all the products of TG and PG in order to collect what is known about the role of peptides other than melatonin. The results available today are often unclear and not linear. These peptides have not been well studied and defined over the years. In this review we hope to awake the interest of the scientific community in them and in their future pharmacological applications.

Hypoxia-inducible factor (HIF1alpha) inhibition modulates cumulus cell function and affects bovine oocyte maturation in vitro†

Various metabolic and hormonal factors expressed in cumulus cells are positively correlated with the in vitro maturation (IVM) of oocytes. However, the role of hypoxia sensing both during maturation of cumulus–oocyte complexes (COCs) as well as during the resumption of meiosis remains uncertain. HIF1alpha plays major roles in cellular responses to hypoxia, and here we investigated its role during bovine COC maturation by assessing the expression of related genes in cumulus cells. COCs were divided into the following groups: immature (control), in vitro matured (IVM/control), or matured in the presence of a blocker of HIF1alpha activity (echinomycin, IVM/E). We found an inhibition of cumulus cell expansion in IVM/E, compared with the IVM/control. Transcript levels of several factors (n = 13) were assessed in cumulus cells. Decreased expression of HAS2, TNFAIP6, TMSB4, TMSB10, GATM, GLUT1, CX43, COX2, PTGES, and STAR was found in IVM/E (P < 0.05). Additionally, decreased protein levels were detected for STAR, HAS2, and PCNA (P < 0.05), while activated-Caspase 3 remained unaffected in IVM/E. Progesterone output decreased in IVM/E. The application of PX-478, another blocker of HIF1alpha expression, yielded identical results. Negative effects of HIF1alpha suppression were further observed in the significantly decreased oocyte maturation and blastocyst rates from COCs matured with echinomycin (P < 0.05) or PX-478 (P < 0.05). These results support the importance of HIF1alpha for COC maturation and subsequent embryo development. HIF1alpha is a multidirectional factor controlling intercellular communication within COCs, steroidogenic activity, and oocyte development rates, and exerting effects on blastocyst rates.

Ependymoma Pediatric Brain Tumor Protein Fingerprinting by Integrated Mass Spectrometry Platforms: A Pilot Investigation

Ependymoma pediatric brain tumor occurs at approximate frequencies of 10-15% in supratentorial and 20-30% in posterior fossa regions. These tumors have an almost selective response to surgery and relative and confirmed resistance to radiotherapy and chemotherapic agents, respectively. Alongside histopathological grading, clinical and treatment evaluation of ependymomas currently consider the tumor localization and the genomic outlined associated molecular subgroups, with the supratentorial and the posterior fossa ependymomas nowadays considered diverse diseases. On these grounds and in trying to better understand the molecular features of these tumors, the present investigation aimed to originally investigate the proteomic profile of pediatric ependymoma tissues of different grade and localization by mass spectrometry platforms to disclose potential distinct protein phenotypes. To this purpose, acid-soluble and acid-insoluble fractions of ependymoma tumor tissues homogenates were analyzed by LC-MS following both the top-down and the shotgun proteomic approaches, respectively, to either investigate the intact proteome or its digested form. The two approaches were complementary in profiling the ependymoma tumor tissues and showed distinguished profiles for supratentorial and posterior fossa ependymomas and for WHO II and III tumor grades. Top-down proteomic analysis revealed statistically significant higher levels of thymosin beta 4, 10 kDa heat shock protein, non-histone chromosomal protein HMG-17, and mono-/uncitrullinated forms ratio of the glial fibrillary acidic protein (GFAP) fragment 388-432 in supratentorial ependymomas-the same GFAP fragment as well as the hemoglobin alpha- and the beta-chain marked grade II with respect to grade III posterior fossa ependymomas. Gene ontology classification of shotgun data of the identified cancer and the non-cancer related proteins disclosed protein elements exclusively marking tumor localization and pathways that were selectively overrepresented. These results, although preliminary, seem consistent with different protein profiles of ependymomas of diverse grade of aggressiveness and brain region development and contributed to enlarging the molecular knowledge of this still enigmatic tumor.

TMSB10 acts as a biomarker and promotes progression of clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is one of the most common urological malignancies. Identifying novel biomarkers and investigating the underlying mechanism of ccRCC development will be crucial to the management and treatment of ccRCC in patients. Thymosin b10 (TMSB10), a member of the thymosin family, is involved in various physiological processes, including tissue regeneration and inflammatory regulation. Moreover, it has been found to be upregulated in many types of carcinoma. However, its roles in ccRCC remain to be elucidated. The present study aimed to explore the expression of TMSB10 in ccRCC through mining The Cancer Genome Atlas (TCGA) and Oncomine databases, and to investigate the association between TMSB10 expression and clinicopathological factors. Furthermore, immunohistochemistry assays and western blotting were conducted to verify TMSB10 expression levels in human ccRCC tissues and cell lines. Functional analyses were also performed to identify the roles of TMSB10 in vitro. The results revealed that TMSB10 was significantly upregulated in RCC tissues and cell lines. The expression of TMSB10 was closely associated with various clinicopathological parameters. In addition, high expression of TMSB10 predicted poor clinical outcome. The receiver operating characteristic curve revealed that TMSB10 could sufficiently distinguish the tumor from normal kidney (area under the curve = 0.9543, P<0.0001). Furthermore, knockdown of TMSB10 impaired the proliferation of ccRCC cells, and attenuated cell and invasion in vitro. In addition, TMSB10 knockdown downregulated reduced the phosphorylation of PI3K and the expression of vascular endothelial growth factor. In conclusion, the present study demonstrated that high expression of TMSB10 could serve as a useful diagnostic and prognostic biomarker and a potential therapeutic target for ccRCC.

Fusion of thymosin alpha 1 with mutant IgG1 CH3 prolongs half-life and enhances antitumor effects in vivo

Thymosin alpha 1 (Tα1) is an immunomodulatory polypeptide secreted from the thymus. Tα1 has a wide range of biological functions, such as immunomodulation and endocrine regulation. Tα1 also displays antiviral and antitumor activities. Tα1 has been successfully used in clinical adjuvant therapy for solid tumors to improve the immune response of patients undergoing chemotherapy and radiotherapy. However, the half-life of Tα1 in the body is short, so frequent administration is required to maintain efficacy. In order to improve the pharmacokinetic profile of Tα1, we linked the mutated CH3 (mCH3) fragment of IgG1 (human) to the C-terminus of Tα1 to produce a long-acting fusion protein, Tα1-mCH3. The half-life of Tα1-mCH3 (47 h) was substantially increased compared with that of the parent molecule Tα1 (3 h). In vivo studies indicated that mCH3 fusion retained the original biological activity of Tα1, and Tα1-mCH3 showed slightly better immunomodulatory effect than Ta1. In the 4 T1 and B16F10 tumor xenograft models, Tα1-mCH3 induced a greater abundance of CD4⁺ and CD8⁺ T-cells in tumor tissues compared with Ta1. Tα1-mCH3 exhibited better effect in promoting the production of IL-2 and IFN-γ compared with Tα1. Therefore, Tα1-mCH3 more efficiently inhibited the growth of 4 T1 and B16F10 tumors than Tα1. In conclusion, fusion with mCH3 is an attractive strategy to lengthen the half-life and increase the activity of Tα1.

Exosomal cyclophilin A as a novel noninvasive biomarker for Epstein-Barr virus associated nasopharyngeal carcinoma

Exosomes have emerged as novel vehicles for proteins and other contents in cancer progression. Cyclophilin A (CYPA) is a pivotal member of immunophilin family. Whether CYPA can be detected in sera of nasopharyngeal carcinoma (NPC) patients remains to be explored. Epstein-Barr virus (EBV) is the first identified human tumor virus and is a causative agent of NPC. The antibody of EBV capsid antigen immunoglobulin A (EBV-VCA-IgA) is a known biomarker of NPC, with a proportion of no more than 70% being detected positively. Hence, novel biomarkers need to be discovered for early diagnosis, prognosis, and monitoring of EBV-associated NPC. A total of 110 NPC and 36 normal control serum samples were collected. Exosomes from these samples were extracted. The mRNA and protein expression levels of the above samples were validated by reverse transcription -quantitative polymerase chain reaction, Western blotting, or enzyme-linked immunosorbent assay (ELISA). Finally, the results demonstrated that both the serum and exosomal CYPA levels of NPC patients were significantly higher than that of normal cases. In addition, exosomal CYPA had a much higher level than that in the whole sera. The positive rate of EBV-VCA-IgA antibody was 68.2% in NPC sera, and noticeably, among the cases with EBV-VCA-IgA negative, 80% of them presented high levels of CYPA above the standard (cutoff value). In particular, CYPA in exosomes was uniformly with higher significance than that in whole sera. Combined analysis of CYPA protein and EBV-VCA-IgA antibody showed a greatly higher discriminatory ability in diagnosis of NPC. Moreover, exosomal CYPA level had a positive correlation with that of the EBV-encoded latent membrane protein 1 (LMP1) in exosomes. EBV-positive cancer cells secreted significantly higher levels of exosomal CYPA. This study established the utility of circulating exosomal CYPA as a potential noninvasive diagnostic biomarker for EBV-associated NPC.

Thymosin plus cisplatin with vinorelbine or gemcitabine for non-small cell lung cancer: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

  To evaluate the efficacy and safety of thymosin plus cisplatin with vinorelbine (NP)/gemcitabine with cisplatin (GP) program for patients with non-small cell lung cancer (NSCLC).

METHODS

  We searched PubMed, EMBASE, Cochrane Library, ISI Web of Knowledge, Chinese Biomedical Database and other databases. Randomized controlled trials (RCT) comparing thymosin plus NP/GP with NP/GP alone for patients with NSCLC were eligible for our study. We evaluated the quality of included studies using Cochrane Handbook standards. Data analysis was conducted using Review Manager 5.0 software (The Nordic Cochrane Centre, Copenhagen, Denmark).

RESULTS

  Ten RCT including 724 patients were eligible. The results of our study showed that: compared with an NP program alone, thymosin plus NP could increase overall response rate (odds ratio (OR) 1.86; 95% confidence interval (CI) 1.08-3.20), tumor control rate (OR 3.06; 95% CI: 1.36-6.88) and 1-year survival rate (OR 3.05; 95% CI: 1.34-6.96), improve the quality of life (OR 3.39; 95% CI: 1.54-7.47), CD4 (mean difference (MD) 6.7; 95% CI: 3.52-9.88) and NK cells (MD 6.53; 95% CI: 3.6-9.47). Compared with a GP program alone, thymosin plus GP could increase overall response rate (OR 1.67; 95% CI: 1.09-2.55), tumor control rate (OR 2.38; 95% CI: 1.01-5.62), improve quality of life (OR 3.84; 95% CI: 1.97-7.48), CD4 (MD 14.82; 95% CI: 8.05-21.59) and NK (MD 16.96; 95% CI: 4.90-29.03) Conclusion:  Thymosin plus NP/GP is a better choice for patients with advanced NSCLC than NP/GP alone.

Extrathymic production of thymulin induced by oxidative stress, heat shock, apoptosis, or necrosis

Thymic peptides are immune regulators produced mainly in the thymus. However, thymic peptides such as thymosin-α and thymopoietin have precursors widely expressed outside the thymus, localized in cell nuclei, and involved in vital nuclear functions. In stress-related conditions, they can relocalize. We hypothesized that another thymic peptide, thymulin, could be similarly produced by non-thymic cells during stress and have a precursor therein. Non-thymic cells, including macrophages and fibroblasts, were exposed to oxidative stress, heat, apoptosis, or necrosis. Extracellular thymulin was identified in media of both cell types 2 h after exposure to stress or lethal signals. Therefore, thymulin is released by non-thymic cells. To examine possible thymulin precursors in non-thymic cells, macrophage lysates were analyzed by western blotting. Bands stained with anti-thymulin antibody were detected in two locations, approximately 60 kDa and 10 kDa, which may be a possible precursor and intermediate. All of the exposures except for heat were effective for induction of the 10 kDa protein. BLAST search using thymulin sequence identified SPATS2L, an intranucleolar stress-response protein with molecular weight of 62 kDa, containing thymulin-like sequence. Comparisons of blots stained with anti-thymulin and anti-SPATS2L antibodies indicate that SPATS2L may be a possible candidate for the precursor of thymulin.

Prokaryotic-expressed porcine IFNα1-THYα1 fusion proteins exert IFN and THY activities in vitro

Combined use of interferon (IFN) and thymosin (THY) holds a stronger antiviral effect than when applied individually because of their coordination and complementary action. In this study, prokaryotic expressed porcine IFNα1 (poIFNα1) or the porcine IFNα1-THYα1 fusion protein coding with the Escherichia coli preferred codon sequences connected by the three different linkers were gained in the unlabeled pRSFDDuet-1 expression systems and purified using the strong anion-exchange chromatography and hydrophobic chromatography (among which, one was digested by thrombin because the cleavage site was included in the linker). Then, the activities of IFN and THY in the fusion protein were detected using the cytopathic effect inhibition assay and T-cell activity assays. SDS PAGE and western blotting results showed that the poIFNα1 or the three poIFNα1-THYα1 fusion proteins with three different linkers were expressed solubly in E. coli. The poIFNα1 protein and three types of poIFNα1-THYα1 fusion proteins with >90% purity were gained. The poIFNα1-LinkerB-THYα1 fusion protein showed the highest interferon activity compared with the others (P < 0.001), and the poIFNα1-LinkerA-THYα1 fusion protein highest thymosin activity (P < 0.05). In this study, a preliminary experiment was conducted for the expression of the poIFNα1 and THYα1 fusion proteins.

High expression of thymosin beta 10 predicts poor prognosis for hepatocellular carcinoma after hepatectomy

Background

Thymosin beta 10 (Tbeta10) overexpression has been reported in a variety of human cancers. However, the role of Tbeta10 in hepatocellular carcinoma (HCC) remains unclear. The aim of the present study was to analyze Tbeta10 expression in tumor and matched non-tumorous tissues, and to assess its prognostic significance for HCC after hepatectomy.

Methods

The level of Tbeta10 mRNA and protein in tumor and matched non-tumorous tissues was evaluated in 26 fresh HCC cases by reverse transcription-polymerase chain reaction (RT-PCR) and western blot. Additionally, Tbeta10 protein expression in 196 HCC was analyzed by immunohistochemistry (IHC) and correlated with clinicopathological characteristics and survival.

Results

Results from RT-PCR and western blot analysis show that the levels of Tbeta10 mRNA and protein were significantly higher in tumor tissues of HCC, compared to that in matched non-tumorous tissues (P = 0.01 and P <0.001, respectively). IHC staining showed that high expression of Tbeta10 was detected in 58.2% (114/196) of HCC cases. High expression of Tbeta10 was significantly associated with advanced TNM stage (P <0.001). Survival analysis demonstrated that high Tbeta10 was related to shorter overall survival (OS) (P = 0.000) and disease-free survival (DFS) (P = 0.000). Multivariate analysis showed that high expression of Tbeta10 was an independent prognostic factor for both OS (P = 0.001, HR = 4.135, 95% CI: 2.603 to 6.569) and DFS (P = 0.001, HR = 2.021, 95% CI: 1.442 to 2.832). Subgroup analysis revealed that high expression of Tbeta10 predicts poorer survival for early and advanced stage.

Conclusions

Tbeta10 protein abnormal expression might contribute to the malignant progression of HCC. High expression of Tbeta10 predicts poor prognosis in patients with HCC after hepatectomy.

A novel dimeric thymosin beta 4 with enhanced activities accelerates the rate of wound healing

OBJECTIVE

Thymosin beta 4 (Tβ4) is a peptide with 43 amino acids that is critical for repair and remodeling tissues on the skin, eye, heart, and neural system following injury. To fully realize its utility as a treatment for disease caused by injury, the authors constructed a cost-effective novel Tβ4 dimer and demonstrated that it was better able to accelerate tissue repair than native Tβ4.

METHODS

A prokaryotic vector harboring two complete Tβ4 genes with a short linker was constructed and expressed in Escherichia coli. A pilot-scale fermentation (10 L) was performed to produce engineered bacteria and the Tβ4 dimer was purified by one-step hydrophobic interaction chromatography. The activities of the Tβ4 dimer to promote endothelial cell proliferation, migration, and sprouting were assessed by tetramethylbenzidine (methylthiazol tetrazolium), trans-well, scratch, and tube formation assays. The ability to accelerate dermal healing was assessed on rats.

RESULTS

After fermentation, the Tβ4 dimer accounted for about 30% of all the bacteria proteins. The purity of the Tβ4 dimer reached 98% after hydrophobic interaction chromatography purification. An average of 562.4 mg/L Tβ4 dimer was acquired using a 10 L fermenter. In each assay, the dimeric Tβ4 exhibited enhanced activities compared with native Tβ4. Notably, the ability of the dimeric Tβ4 to promote cell migration was almost two times higher than that of Tβ4. The rate of dermal healing in the dimeric Tβ4-treated rats was approximately 1 day faster than with native Tβ4-treated rats.

CONCLUSION

The dimeric Tβ4 exhibited enhanced activity on wound healing than native Tβ4, and the purification process was simple and cost-effective. This data could be of significant benefit for the high pain and morbidity associated with chronic wounds disease. A better strategy to develop Tβ4 as a treatment for other diseases caused by injuries such as heart attack, neurotrophic keratitis, and multiple sclerosis was also described.

Suppression of thymosin β10 increases cell migration and metastasis of cholangiocarcinoma

BACKGROUND

Thymosin β10 (Tβ10) expression is associated with malignant phenotypes in many cancers. However, the role and mechanisms of Tβ10 in liver fluke-associated cholangiocarcinoma (CCA) are not fully understood. In this study, we investigated the expression of Tβ10 in CCA tumor tissues and cell lines as well as molecular mechanisms of Tβ10 in tumor metastasis of CCA cell lines.

METHODS

Tβ10 expression was determined by real time RT-PCR or immunocytochemistry. Tβ10 silence or overexpression in CCA cells was achieved using gene delivery techniques. Cell migration was assessed using modified Boyden chamber and wound healing assay. The effect of silencing Tβ10 on CCA tumor metastasis was determined in nude mice. Phosphorylation of ERK1/2 and the expression of EGR1, Snail and matrix metalloproteinases (MMPs) were studied.

RESULTS

Ten pairs of CCA tissues (primary and metastatic tumors) and 5 CCA cell lines were studied. With real time RT-PCR and immunostaining analysis, Tβ10 was highly expressed in primary tumors of CCA; while it was relatively low in the metastatic tumors. Five CCA cell lines showed differential expression levels of Tβ10. Silence of Tβ10 significantly increased cell migration, invasion and wound healing of CCA cells in vitro; reversely, overexpression of Tβ10 reduced cell migration compared with control cells (P<0.05). In addition, silence of Tβ10 in CCA cells increased liver metastasis in a nude mouse model of CCA implantation into the spleen. Furthermore, silence of Tβ10 activated ERK1/2 and increased the expression of Snail and MMPs in CCA cell lines. Ras-GTPase inhibitor, FPT inhibitor III, effectively blocked Tβ10 silence-associated ERK1/2 activation, Snail expression and cell migration.

CONCLUSIONS

Low expression of Tβ10 is associated with metastatic phenotype of CCA in vitro and in vivo, which may be mediated by the activation of Ras, ERK1/2 and upregulation of Snail and MMPs. This study suggests a new molecular pathway of CCA pathogenesis and a novel strategy to treat or prevent CCA metastasis.

The Escherichia coli-derived thymosin β4 concatemer promotes cell proliferation and healing wound in mice

Thymosin β4 (Tβ4) is one of the most promising thymosins for future clinical applications, and it is anticipated that commercial demand for Tβ4 will increase. In order to develop a new approach to produce recombinant Tβ4, a 168 bp DNA (termed Tβ4) was designed based on the Tβ4 protein sequence and used to express a 4 × Tβ4 concatemer (four tandem copies of Tβ4, termed 4 × Tβ4) together with a histidine tag (6 × His) in E. coli (strain BL21). SDS-PAGE and western blot analysis were used to confirm that a recombinant 4 × Tβ4 protein of the expected size (30.87 kDa) was produced following the induction of the bacterial cultures with isopropyl β-D-thiogalactoside (IPTG). The E. coli-derived 4 × Tβ4 was purified by Ni-NTA resin, and its activities were examined with regard to both stimulating proliferation of the mice spleen cells in vitro and in vivo wound healing. The results demonstrate that these activities of the E. coli-derived recombinant 4 × Tβ4 were similar or even better than existing commercially obtained Tβ4. This production strategy therefore represents a potentially valuable approach for future commercial production of recombinant Tβ4.

Thymosin beta 15A (TMSB15A) is a predictor of chemotherapy response in triple-negative breast cancer

Background:

Biomarkers predictive of pathological complete response (pCR) to neoadjuvant chemotherapy (NACT) of breast cancer are urgently needed.

Methods:

Using a training/validation approach for detection of predictive biomarkers in HER2-negative breast cancer, pre-therapeutic core biopsies from four independent cohorts were investigated: Gene array data were analysed in fresh frozen samples of two cohorts (n=86 and n=55). Quantitative reverse transcription polymerase chain reaction (qRT–PCR) was performed in formalin-fixed, paraffin-embedded (FFPE) samples from two neoadjuvant phase III trials (GeparTrio, n=212, and GeparQuattro, n=383).

Results:

A strong predictive capacity of thymosin beta 15 (TMSB15A) gene expression was evident in both fresh frozen cohorts (P<0.0001; P<0.0042). In the GeparTrio FFPE training cohort, a significant linear correlation between TMSB15A expression and pCR was apparent in triple-negative breast cancer (TNBC) (n=61, P=0.040). A cutoff point was then defined that divided TNBC into a low and a high expression group (pCR rate 16.0% vs 47.2%). Both linear correlation of TMSB15A mRNA levels (P=0.017) and the pre-defined cutoff point were validated in 134 TNBC from GeparQuattro (pCR rate 36.8% vs 17.0%, P=0.020). No significant predictive capacity was observed in luminal carcinomas from GeparTrio and GeparQuattro.

Conclusion:

In TNBC, TMSB15A gene expression analysis might help to select patients with a high chance for pCR after NACT.

Thymosin β4 is a novel potential prognostic marker in gastrointestinal stromal tumors

Thymosin beta-4 (Tβ(4)) is a major actin-sequestering molecule that contributes to cell growth, differentiation, motility, survival, mitosis and angiogenesis. It is overexpressed in certain type of carcinoma and fibrosarcoma cell lines and is associated with metastatic potential. The aim of this study was to investigate the relationship between Tβ(4) expression and clinicopathologic features and VEGF status in gastrointestinal stromal tumors (GISTs). Retrospectively, 60 GISTs were re-examined and immunohistochemistry for Tβ(4) and VEGF was performed. Increased expression of Tβ(4) and VEGF was observed in 26 (43.3%) and in 19 (31.6%) of the tumors, respectively. Tβ(4) expression was positively correlated with VEGF expression (p < 0.01). Tβ(4) and VEGF expression were significantly associated with tumor size (p = 0.00 and p = 0.02, respectively) and high mitosis (p = 0.03 and p = 0.00, respectively). Although Tβ(4) expression was positively associated with pleomorphism (p = 0.01), VEGF expression was positively associated with necrosis (p = 0.03). Tβ(4) expression was related with local recurrence and/or metastasis (p = 0.03), but VEGF expression was not (p = 0.12). We firstly demonstrate the presence of Tβ(4) protein in GISTs. Our study reveals that increased expression of Tβ(4) could be considered as an indicator of aggressive behavior of tumor.

Expression pattern of thymosin beta 4 in the adult human liver

Thymosin beta-4 (Tβ4) is a member of beta-thymosins, a family of small peptides involved in polymerization of G-actin, and in many critical biological processes including apoptosis, cell migration, angiogenesis, and fibrosis. Previous studies in the newborn liver did not reveal any significant reactivity for Tβ4 during the intrauterine life. The aim of the present study was to investigate by immunohistochemistry Tβ4 expression in the adult normal liver. Thirty-five human liver samples, including 11 needle liver biopsies and 24 liver specimens obtained at autopsy, in which no pathological change was detected at the histological examination, were immunostained utilizing an anti-Tβ4 commercial antibody. Tβ4 was detected in the hepatocytes of all adult normal livers examined. A zonation of Tβ4 expression was evident in the vast majority of cases. Immunostaining was preferentially detected in zone 3, while a minor degree of reactivity was detected in periportal hepatocytes (zone 1). At higher power, Tβ4-reactive granules appeared mainly localized at the biliary pole of hepatocytes. In cases with a strong immunostaining, even perinuclear areas and the sinusoidal pole of hepatocytes appeared interested by immunoreactivity for Tβ4. The current work first evidences a strong diffuse expression of Tβ4 in the adult human liver, and adds hepatocytes to the list of human cells able to synthesize large amounts of Tβ4 in adulthood. Moreover, Tβ4 should be added to the liver proteins characterized by a zonate expression pattern, in a descending gradient from the terminal vein to the periportal areas of the liver acinus. Identifying the intimate role played by this peptide intracellularly and extracellularly, in physiology and in different liver diseases, is a major challenge for future research focusing on Tβ4.

Expression, purification and characterization of a novel soluble human thymosin alpha1 concatemer exhibited a stronger stimulation on mice lymphocytes proliferation and higher anti-tumor activity

Thymosin alpha 1 (Tα1) has immunomodulatory and anti-tumor effects in patients and has been commercialized in worldwide. An innovative technique is therefore impending to achieve high-yield expression and purification of Tα1 to meet the increasing requirements for clinical applications. Tα1 can enhance T cells, dendritic cells and antibody responses, and also augment an anti-tumor immune response. In the current study, we developed a novel technique to produce Tα1 concatemer and investigated its capability in anti-tumor immunotherapy. We expressed the recombinant 2×Tα1 concatemer protein (Tα1② protein) in Escherichia coli. The purity of Tα1② was higher than 95% as assessed by HPLC analysis. In vitro, Tα1② could stimulate the proliferation of mouse splenic lymphocyte, and increase the apoptosis of tumor cell lines. In vivo, Tα1② significantly inhibited the tumor growth in B16 tumor-bearing mice. Compared with Tα1, the Tα1② is of more effective bioactivity than Tα1. The purified Tα1② is a promising substitute for synthetic Tα1 because of its potent anti-tumor effects. We concluded that the expression system for Tα1 concatemer was constructed successfully, which could serves as a highly efficient tool for the production of large quantities of the highly active protein.

Thymosins β-4 and β-10 are expressed in bovine ovarian follicles and upregulated in cumulus cells during meiotic maturation

β-Thymosins are small proteins that regulate the actin cytoskeleton and are involved in cell motility, differentiation, the induction of metalloproteinases, in anti-inflammatory processes and tumourigenesis. However, their roles in the ovary have not yet been elucidated. Using transcriptomics and real time reverse transcription-polymerase chain reaction validation, the present study demonstrates that thymosin β-4 (TMSB4) and thymosin β-10 (TMSB10) are upregulated in bovine cumulus cells (CCs) during in vitro maturation of cumulus-oocyte complexes (COCs) in parallel with an increase in mRNA expression of HAS2, COX2 and PGR genes. Using immunocytochemistry, both proteins were found to be localised mainly in granulosa cells, CCs and oocytes, in both the cytoplasm and nucleus, as well as being colocalised with F-actin stress fibres in CCs. Using different maturation mediums, we showed that the expression of TMSB10, but not TMSB4, was positively correlated with COC expansion and progesterone secretion and negatively correlated with apoptosis. Immunofluorescence, coupled with terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL), demonstrated the absence of TMSB4 and/or TMSB10 in apoptotic cells. TMSB10 expression was higher in COCs matured in vivo than in vitro, and differences related to the age of the animal were observed. TMSB4 and/or TMSB10 expression was unchanged, whereas HAS2 overexpressed in CCs from oocytes that developed to the blastocyst stage in vitro compared with those that did not. Thus, TMSB4 and/or TMSB10 ovarian expression patterns suggest that these two thymosins may be involved in cumulus modifications during maturation.

Thymus hormones as prospective anti-inflammatory agents

IMPORTANCE OF THE FIELD

Inflammatory diseases are characterized by severe immune imbalances, leading to excessive or inappropriate release of mediators, which, in turn, result in massive damage to organs and systems. Effective means to control inappropriate immune reactions are often life-critical needs. Available data on the role of thymus-derived hormones in inflammation show their great potential.

AREAS COVERED IN THIS REVIEW

The review aims to systematize information for the last two decades on immune system regulation by thymic peptide hormones, with a primary focus on the role of these hormones in the systemic inflammatory response and inflammatory diseases. Anti-inflammatory potential of three thymic hormones - thymulin, thymosin-alpha, and thymopoietin - is discussed, reviewing recently published clinical and experimental studies.

WHAT THE READER WILL GAIN

Our analysis revealed the regulation of inflammatory processes via thymic hormones that could be prospective for therapeutic application. This regulation may be mediated through thymic hormone effects on peripheral immune cell activities and bidirectional coupling between thymic hormones and the hypothalamic-pituitary-adrenal axis.

TAKE-HOME MESSAGE

In view of the role of thymic hormones in immune and neuroendocrine systems, they could be suitable as therapeutic agents for inflammation.

Thymosin alpha 1: biological activities, applications and genetic engineering production

Thymosin alpha 1 (Tα1), a 28-amino acid peptide, was first described and characterized from calf thymuses in 1977. This peptide can enhance T-cell, dendritic cell (DC) and antibody responses, modulate cytokines and chemokines production and block steroid-induced apoptosis of thymocytes. Due to its pleiotropic biological activities, Tα1 has gained increasing interest in recent years and has been used for the treatment of various diseases in clinic. Accordingly, there is an increasing need for the production of this peptide. So far, Tα1 used in clinic is synthesized using solid phase peptide synthesis. Here, we summarize the genetic engineering methods to produce Tα1 using prokaryotic or eukaryotic expression systems. The effectiveness of these biological products in increasing the secretion of cytokines and in promoting lymphocyte proliferation were investigated in vitro studies. This opens the possibility for biotechnological production of Tα1 for the research and clinical applications.

Bioactivity and pharmacokinetics of two human serum albumin-thymosin alpha1-fusion proteins, rHSA-Talpha1 and rHSA-L-Talpha1, expressed in recombinant Pichia pastoris

Thymosin-alpha1 (Talpha1) is indicated for the treatment of certain viral infections, including hepatitis B and C, and cancers, such as melanoma. In this paper, the fusion genes encoding human serum albumin (HSA) and Talpha1 with (rHSA-L-Talpha1) and without a linker peptide (rHSA-Talpha1) were constructed and overexpressed in P. pastoris. Through the process of ion interaction chromatography (Q-Sepharose F.F), hydrophobic interaction chromatography (Phenyl Sepharose HP) and affinity chromatography (Blue Sepharose F.F), the purity of fusion proteins was greater than 97%. In contrast to the reactivity of normal spleen cells to Con A, the data of in vitro murine spleen lymphocytes proliferation experiment suggested that spleen cells achieved a higher degree of T cell maturation after rHSA-L-Talpha1, rHSA-Talpha1 and Talpha1 treatments, respectively. Moreover, rHSA-L-Talpha1, rHSA-Talpha1 and Talpha1 can also antagonize dexamethasone-induced apoptosis of thymocyte sub-populations. In hydrocortisone-induced immunosuppression mice (in vivo experiments), after subcutaneous injections with two fusion proteins and Talpha1 for seven consecutive days, the net increment of body weight, the spleen index and the thymus index were significantly improved. Simultaneously, the increase in SOD level and the decrease in MDA level in plasma were observed. The pharmacokinetic data of rHSA-L-Talpha1 and rHSA-Talpha1 administered in rats showed an improved pharmacokinetic profile with a conspicuous prolonged half life. The analysis of bioactivity and pharmacokinetics suggested that fusion proteins rHSA-L-Talpha1 and rHSA-Talpha1 were new drug candidates.

Overexpression of the natural tetrapeptide acetyl-N-ser-asp-lys-pro derived from thymosin beta4 in neoplastic diseases

The natural tetrapeptide acetyl-ser-asp-lys-pro (AcSDKP) is formed in vivo by enzymatic cleavage of the N terminus of thymosin beta4 by prolyl oligopeptidase (POP). Recently, AcSDKP was shown to promote angiogenesis. Because of the critical role of neovascularization in cancer development, the levels of AcSDKP and POP activity in a number of different malignant tissues were investigated. Our studies revealed that AcSDKP levels were markedly elevated in neoplastic diseases including hematologic malignancies and solid neoplasms. Consistent with this finding, the enhanced activity of POP was also detected in all analyzed specimens of cancer tissues. Both these novel findings are in concert with the previously reported overexpression of thymosin beta4 in a large variety of malignant tumors and with its potential role in cancerogenesis. The physiological relevance of these findings awaits further studies; however, our first results strongly suggest a key role for AcSDKP in the pathogenesis of cancer.

Thymosin beta 4 expression in normal skin, colon mucosa and in tumor infiltrating mast cells

Mast cells (MCs) are metachromatic cells that originate from multipotential hemopoietic stem cells in the bone marrow. Two distinct populations of MCs have been characterized: mucosal MCs are tryptase-positive while mast cells in skin contain tryptase and chymase. We now show that a sub-population of MCs is highly immunoreactive for thymosin beta4, as revealed by immunohistochemical analyses of normal skin, normal colon mucosa and salivary gland tumors. Four consecutive serial sections from each case were immunostained for thymosin beta4 (Tbeta4), chymase, tryptase and stained for toluidine blue. In skin biopsies, MCs showed a comparable immunoreactivity for Tbeta4, chymase and tryptase. In normal colon mucosa the vast majority of mucosal MCs expressed a strong cytoplasmic immunoreactivity for tryptase and for Tbeta4, in the absence of chymase reactivity. A robust expression of Tbeta4 was detected in tumor-infiltrating and peritumoral mast cells in salivary gland tumors and breast ductal infiltrating carcinomas. Tumor-infiltrating MCs also showed a strong immunoreactivity for chymase and tryptase. In this paper, we first demonstrate that normal dermal and mucosal mast cells exhibit strong expression of thymosin beta4, which could be considered a new marker for the identification of mast cells in skin biopsies as well as in human tumors. The possible relationship between the degree of Tbeta4 expression in tumor-infiltrating mast cells and tumor behaviour warrants further consideration in future investigations.

Thymosin β4 has tumor suppressive effects and its decreased expression results in poor prognosis and decreased survival in multiple myeloma

Thymosin beta4 (Tbeta4) is a polypeptide involved in cellular proliferation, differentiation, and migration, over-expressed in several tumor entities. We evaluated its expression and function in 298 newly diagnosed multiple myeloma patients and the murine 5TMM model. Mean Tbeta4 expression was significantly lower in myeloma cells compared to normal plasma cells (P<0.001). The same observation can be made in the 5TMM-mouse model by qRT-PCR and ELISA. Here, Tbeta4 overexpression by lentiviral transduction of 5T33MMvt-cells led to significantly decreased proliferative and migratory capacities and increased sensitivity to apoptosis-induction. Mice injected with Tbeta4 over-expressing myeloma cells showed a longer survival compared to mice injected with controls (88,9 vs. 65,9 days, P<0.05). In 209 MM patients treated with high-dose therapy and autologous stem cell transplantation, expression of Tbeta4 below the median was associated with a significantly shorter event free survival (37.6 vs. 26.2 months, P<0.05). In conclusion, our results indicate a possible tumor suppressive function of Tbeta4.

Thymostimulin in advanced hepatocellular carcinoma: a phase II trial

Background

Thymostimulin is a thymic peptide fraction with immune-mediated cytotoxicity against hepatocellular carcinoma in vitro. In a phase II trial, we investigated safety and efficacy including selection criteria for best response in advanced or metastasised hepatocellular carcinoma.

Methods

44 patients (84 % male, median age 69 years) not suitable or refractory to conventional therapy received thymostimulin 75 mg subcutaneously five times per week for a median of 8.2 months until progression or complete response. 3/44 patients were secondarily accessible to local ablation or chemoembolisation. Primary endpoint was overall survival, secondary endpoint tumor response or progression-free survival. A multivariate Cox's regression model was used to identify variables affecting survival.

Results

Median survival was 11.5 months (95% CI 7.9–15.0) with a 1-, 2- and 3-year survival of 50%, 23% and 9%. In the univariate analysis, a low Child-Pugh-score (p = 0.01), a low score in the Okuda- and CLIP-classification (p < 0.001) or a low AFP-level (p < 0.001) were associated with better survival, but not therapy modalities other than thymostimulin (p = 0.1) or signs of an invasive HCC phenotype such as vascular invasion (p = 0.3) and metastases (p = 0.1). The only variables independently related to survival in the Cox's regression model were Okuda stage and presence of liver cirrhosis (p < 0.01) as well as response to thymostimulin (p < 0.05). Of 39/44 patients evaluable for response, two obtained complete responses (one after concomitant radiofrequency ablation), five partial responses (objective response 18%), twenty-four stable disease (tumor control rate 79%) and eight progressed. Median progression-free survival was 6.4 months (95% CI 0.8–12). Grade 1 local reactions following injection were the only side effects.

Conclusion

Outcome in our study rather depended on liver function and intrahepatic tumor growth (presence of liver cirrhosis and Okuda stage) in addition to response to thymostimulin, while an invasive HCC phenotype had no influence in the multivariate analysis. Thymostimulin could therefore be considered a safe and promising candidate for palliative treatment in a selected target population with advanced hepatocellular carcinoma, in particular as component of a multimodal therapy concept.

Trial registration

Current Controlled Trials ISRCTN29319366.

Thymosin alpha 1 improves severe acute pancreatitis in rats via regulation of peripheral T cell number and cytokine serum level

AIM

The aim of this study was to investigate the effect of thymosin alpha 1 (TA1) on severe acute pancreatitis (SAP) in rats.

METHODS

Healthy Sprague-Dawley rats (n = 72) were randomly divided into four groups: control group, SAP group, and two TA1 treated groups. SAP was induced by injection of 5% sterile sodium taurocholate into the biliopancreatic duct (BPD), after which TA1 was given subcutaneously at 0 and 2 h at a dose of 100 microg/kg. The rats were killed at 3, 6 and 12 h, respectively. Serum amylase and lipase, interleukin (IL)-1beta, tumor necrosis factor-alpha (TNF-alpha), pancreatic wet/dry weight ratio and the percentage of CD3/CD4+/CD8+ T cells in peripheral blood mononuclear cells (PBMC) were measured. Next, 30 rats were randomly divided into three groups (each group containing 10 animals): SAP group (S) and two TA1 treated groups. The effects of TA1 on the survival of SAP were assessed 72 h after the induction of SAP.

RESULTS

There was no significant change in the serum amylase and lipase levels after TA1 administration. Levels of serum IL-1beta, TNF-alpha and pancreatic wet/dry weight ratio were significantly reduced after TA1-treatment. Application of TA1 significantly balanced CD3/CD4+/CD8+ T cells of PBMC and improved histological scores and the survival rate.

CONCLUSION

TA1 can reduce pancreatic inflammation by regulating differentiation of CD3/CD4+ T cells and decreasing the release of cytokines, thus attenuates pancreatic severity in SAP rats.

Thymosin β4 and Ac-SDKP: Tools to mend a broken heart

Thymosin beta4 - an endogenously occurring 43 amino acid peptide - has recently been shown to possess cardioprotective properties in the setting of acute myocardial infarction. This review focuses on the reported mechanisms of action through which Thymosin beta4 might accomplish this effect and the clinical prospects for its use as a therapeutic agent.

Signaling pathways leading to the activation of IKK and MAPK by thymosin alpha1

Thymosin alpha 1 (Talpha1) has therapeutic potential in the treatment of infectious diseases and cancer. However, the exact molecular pathways for Talpha1 action are not fully understood. We found that Talpha1 induces the production of interleukin-6 (IL-6), IL-10, and IL-12 in murine bone marrow-derived macrophages (BMDMs) through IKK and MAPK pathways. Talpha1 triggers the activation of AP-1 and the phosphorylation of JNK and p38. Inhibition of p38 impairs IL-6 production in response to Talpha1. Further, TRAF6 is involved in the activation of JNK and IRAK4 is involved for the activation of IKK and PKCzeta in a Talpha1-induced system. Loss of IRAK4 largely blocked induction of IL-6. Thus, our studies define early signal events that are critical for the Talpha1-induced immune responses.

In vivo sampling of extracellular beta-thymosin by ultrafiltration probes

In vivo detection and monitoring of extracellular beta-thymosin will facilitate the understanding of their biological function and association with disease progression. A novel technique using capillary ultrafiltration (CUF) probes linked to mass spectrometry is capable of sensing extracellular thymosin beta-4 and/or thymosin beta-10 in vivo in wounded skin and other tissue microenvironments. In this review, we highlight the association of extracellular beta-thymosin with skin wound healing and the potential adjuvant effects on vaccination. The fabrication and biological application of CUF probes are also described. Data from CUF probe-captured beta-thymosin may guide future exploration of extracellular beta-thymosin.

Occurrence of thymosin β4 in human breast cancer cells and in other cell types of the tumor microenvironment

Previous studies have shown that the G-actin sequestering polypeptide thymosin beta4 frequently is overexpressed in cancers and that such overexpression correlates to malignant progression. However, the localization of thymosin beta4 in human cancers has not been determined. We now demonstrate that there is a considerable heterogeneity in the cellular distribution of thymosin beta4 in breast cancer. In most tumors examined, cancer cells showed low or intermediate reactivity for thymosin beta4, whereas leukocytes and macrophages showed intense reactivity. In addition, endothelial cells showed variable reactivity to thymosin beta4, whereas myofibroblasts were negative. There was no correlation between the intensity of tumor cell staining and histological grade, whereas there was a tendency toward a correlation between endothelial cell staining and grade. These results demonstrate that multiple cell types within the tumor microenvironment produce thymosin beta4 and that such expression varies from tumor to tumor. Such heterogeneity of expression should be taken into account when the role of thymosin beta4 in tumor biology is assessed.

Efficacy of thymosin alpha-1 and interferon alpha in treatment of chronic viral hepatitis B: A randomized controlled study

AIM: To observe the efficiency and safety of thymosin-α1 treatment in patients with hepatitis B e antigen (HBeAg) and HBV DNA positive chronic hepatitis.

METHODS: Sixty-two patients were randomly divided into groups A and B. The patients in group A received subcutaneous injection of 1.6 mg thymosin-α1, twice a week (T-α1 group) for six months, and the patients in group B received 5 MU interferon alpha (IFN-α) each day for fifteen days, then three times weekly (IFN-α group) for six months. The results between two groups treated with and the group untreated with IFN-α which was followed up for 12 mo (historical control group consisting of 30 patients) were compared, and three groups were comparable between each other (P > 0.05) at baseline (age, sex, clinical history, biochemical, and serological parameters).

RESULTS: At the end of treatment, complete response, which was defined as alanine aminotransferase (ALT) normalization and HBV DNA and HBeAg loss, occurred in 9 of 29 (31.0%) patients in the T-α1 group and in 15 of 33 (45.5%) patients in the IFN-α group (χ² = 1.36, P > 0.05). After a follow-up period of six months, a complete response was observed in 14 of 29 (48.3%) patients in the T-α1 group and in 9 of 33 (27.3%) patients in the IFN-α group (χ² = 2.93, P > 0.05). Compared with the results observed in the historical control (HC) group untreated with IFN-α which was followed up for 12 mo, the rate of complete response was significantly higher in IFN-α group at the end of therapy (1 of 30 vs 15 of 33, χ² = 14.72, P < 0.001) and in the T-α1 group at the end of follow-up (1 of 30 vs 14 of 29, χ² = 15.71, P < 0.001). In T-α1 and IFN-α treatment groups, the area under (the plasma concentration time) curve (AUC) of negative HBV DNA and HBeAg was 34%, 17%, 31% and 19% smaller than that in the HC group. By the end of the follow-up period, the proportions of ALT normalization and negative HBV DNA in the T-α1 group were significantly higher than those in the IFN-α and HC groups. The odds of ALT normalization and negative HBV DNA at the end of the follow-up was three-fold higher in the T-α1 group than in the IFN-α group. Unlike IFN-α, T-α1 was well tolerated by all patients, and no side effects appeared in T-α1 group.

CONCLUSION: The results suggest that a 6-mo course of T-α1 therapy is effective and safe in patients with chronic hepatitis B. T-α1 is able to reduce HBV replication in patients with chronic hepatitis B. Furthermore, T-α1 is better tolerated than IFN-α and can gradually induce more sustained ALT normalization and HBV DNA and HBeAg loss. However, a response rate of 48.3% is still less ideal. A more effective therapeutic approach warrants further study.

Thymosinalpha1 stimulates cell proliferation by activating ERK1/2, JNK, and increasing cytokine secretion in human pancreatic cancer cells

In this study, we investigated the expression and function of thymosinalpha1 (Thyalpha1) in human pancreatic cancer. We found that human pancreatic cancer cell lines Panc-1, Panc03.27, ASPC-1, and PL45 cells significantly over-expressed the mRNA of Thyalpha1 as compared to the normal human pancreatic ductal epithelium (HPDE) cells.. Thyalpha1 mRNA and protein levels were also over-expressed in clinical pancreatic adenocarcinoma specimens. In addition, synthetic Thyalpha1 significantly promoted Panc-1 cell proliferation and increased phosphorylation of ERK1/2 and JNK. Furthermore, Thyalpha1 increased the secretion of multiple cytokines including IL-10, IL-13, and IL-17 in Panc-1 cells. Thus, Thyalpha1 may have a new role in pancreatic cancer pathogenesis.

AcSDKP: a new potential marker of malignancy of the thyroid gland

BACKGROUND AND AIMS

The tetrapeptide Acetyl-Ser-Asp-Lys-Pro (AcSDKP) a physiologic inhibitor of stem-cell proliferation is also known for it's strong angiogenic activity. It has been shown that blood levels of this peptide are increased in some hematological malignancies. However, no data on the concentration of AcSDKP present in solid tumor tissue are available. The aim of our study was to measure tissue concentration of AcSDKP in benign and malignant lesions of the thyroid gland.

PATIENTS AND METHODS

We assessed AcSDKP level in thyroid tissue specimens using enzyme immunoassay kit. The specimens were taken intraoperatively from 20 patients (17 women and 3 men aged 21-68 years): 10 patients with benign nodular goiter and 10 patients with papillary carcinoma of the thyroid gland.

RESULTS

The obtained results show that tissue concentration of AcSDKP in malignant thyroid tumors is five times higher when compared to benign lessions.

CONCLUSION

We conclude that AcSDKP may play a role in the development of the thyroid gland lesions. However, the further investigations concerning the tetrapeptide concentration in other thyroid malignancies, toxic nodular, and Grave's goiter are required to conclude on the eventual use of AcSDKP as a marker of malignancy.