Synuclein gamma expression enhances radiation resistance of breast cancer cells

Cyclic-NDGA Effectively Inhibits Human γ-Synuclein Fibrillation, Forms Nontoxic Off-Pathway Species, and Disintegrates Preformed Mature Fibrils

Parkinson's disease arises from protein misfolding, aggregation, and fibrillation and is characterized by LB (Lewy body) deposits, which contain the protein α-synuclein (α-syn) as their major component. Another synuclein, γ-synuclein (γ-syn), coexists with α-syn in Lewy bodies and is also implicated in various types of cancers, especially breast cancer. It is known to seed α-syn fibrillation after its oxidation at methionine residue, thereby contributing in synucleinopathy. Despite its involvement in synucleinopathy, the search for small molecule inhibitors and modulators of γ-syn fibrillation remains largely unexplored. This work reveals the modulatory properties of cyclic-nordihydroguaiaretic acid (cNDGA), a natural polyphenol, on the structural and aggregational properties of human γ-syn employing various biophysical and structural tools, namely, thioflavin T (ThT) fluorescence, Rayleigh light scattering, 8-anilinonaphthalene-1-sulfonic acid binding, far-UV circular dichroism (CD), Fourier transform infrared spectroscopy (FTIR) spectroscopy, atomic force microscopy, ITC, molecular docking, and MTT-toxicity assay. cNDGA was observed to modulate the fibrillation of γ-syn to form off-pathway amorphous species that are nontoxic in nature at as low as 75 μM concentration. The modulation is dependent on oxidizing conditions, with cNDGA weakly interacting (Kd ∼10-5 M) with the residues at the N-terminal of γ-syn protein as investigated by isothermal titration calorimetry and molecular docking, respectively. Increasing cNDGA concentration results in an increased recovery of monomeric γ-syn as shown by sodium dodecyl sulfate and native-polyacrylamide gel electrophoresis. The retention of native structural properties of γ-syn in the presence of cNDGA was further confirmed by far-UV CD and FTIR. In addition, cNDGA is most effective in suppression of fibrillation when added at the beginning of the fibrillation kinetics and is also capable of disintegrating the preformed mature fibrils. These findings could, therefore, pave the ways for further exploring cNDGA as a potential therapeutic against γ-synucleinopathies.

The Herbal Combination Shu Gan Jie Yu Regulates the SNCG/ER-a/AKT-ERK Pathway in DMBA-Induced Breast Cancer and Breast Cancer Cell Lines Based on RNA-Seq and IPA Analysis

BACKGROUND

Soothing the liver (called Shu Gan Jie Yu in Chinese, SGJY) is a significant therapeutic method for breast cancer in TCM. In this study, 3 liver-soothing herbs, including Cyperus rotundus L., Citrus medica L. var. sarcodactylis Swingle and Rosa rugosa Thunb. were selected and combined to form a SGJY herbal combinatory.

THE AIM OF THE STUDY

To investigate the inhibiting effect of SGJY on breast cancer in vivo and vitro, and to explore the potential mechanisms.

MATERIALS AND METHODS

SGJY herbal combination was extracted using water. A breast cancer rat model was developed by chemical DMBA by gavage, then treated with SGJY for 11 weeks. The tumor tissue was preserved for RNA sequencing and analyzed by IPA software. The inhibition effects of SGJY on MCF-7 and T47D breast cancer cells were investigated by SRB assay and cell apoptosis analysis, and the protein expression levels of SNCG, ER-α, p-AKT and p-ERK were measured by western blotting.

RESULTS

SGJY significantly reduced the tumor weight and volume, and the level of estradiol in serum. The results of IPA analysis reveal SGJY upregulated 7 canonical pathways and downregulated 16 canonical pathways. Estrogen receptor signaling was the key canonical pathway with 9 genes downregulated. The results of upstream regulator analysis reveal beta-estradiol was the central target; the upstream regulator network scheme showed that 86 genes could affect the expression of the beta-estradiol, including SNCG, CCL21 and MB. Additionally, SGJY was verified to significantly alter the expression of SNCG mRNA, CCL21 mRNA and MB mRNA which was consistent with the data of RNA-Seq. The inhibition effects of SGJY exhibited a dose-dependent response. The apoptosis rates of MCF7 and T47D cells were upregulated. The protein expression of SNCG, ER-α, p-AKT and p-ERK were all significantly decreased by SGJY on MCF-7 and T47D cells.

CONCLUSION

The results demonstrate that SGJY may inhibit the growth of breast cancer. The mechanism might involve downregulating the level of serum estradiol, and suppressing the protein expression in the SNCG/ER-α/AKT-ERK pathway.

Characterization of the Prognosis and Tumor Microenvironment of Cellular Senescence-related Genes through scRNA-seq and Bulk RNA-seq Analysis in GC

BACKGROUND

Cellular senescence (CS) is thought to be the primary cause of cancer development and progression. This study aimed to investigate the prognostic role and molecular subtypes of CS-associated genes in gastric cancer (GC).

MATERIALS AND METHODS

The CellAge database was utilized to acquire CS-related genes. Expression data and clinical information of GC patients were obtained from The Cancer Genome Atlas (TCGA) database. Patients were then grouped into distinct subtypes using the "Consesus- ClusterPlus" R package based on CS-related genes. An in-depth analysis was conducted to assess the gene expression, molecular function, prognosis, gene mutation, immune infiltration, and drug resistance of each subtype. In addition, a CS-associated risk model was developed based on Cox regression analysis. The nomogram, constructed on the basis of the risk score and clinical factors, was formulated to improve the clinical application of GC patients. Finally, several candidate drugs were screened based on the Cancer Therapeutics Response Portal (CTRP) and PRISM Repurposing dataset.

RESULTS

According to the cluster result, patients were categorized into two molecular subtypes (C1 and C2). The two subtypes revealed distinct expression levels, overall survival (OS) and clinical presentations, mutation profiles, tumor microenvironment (TME), and drug resistance. A risk model was developed by selecting eight genes from the differential expression genes (DEGs) between two molecular subtypes. Patients with GC were categorized into two risk groups, with the high-risk group exhibiting a poor prognosis, a higher TME level, and increased expression of immune checkpoints. Function enrichment results suggested that genes were enriched in DNA repaired pathway in the low-risk group. Moreover, the Tumor Immune Dysfunction and Exclusion (TIDE) analysis indicated that immunotherapy is likely to be more beneficial for patients in the low-risk group. Drug analysis results revealed that several drugs, including ML210, ML162, dasatinib, idronoxil, and temsirolimus, may contribute to the treatment of GC patients in the high-risk group. Moreover, the risk model genes presented a distinct expression in single-cell levels in the GSE150290 dataset.

CONCLUSION

The two molecular subtypes, with their own individual OS rate, expression patterns, and immune infiltration, lay the foundation for further exploration into the GC molecular mechanism. The eight gene signatures could effectively predict the GC prognosis and can serve as reliable markers for GC patients.

Post-radiation treatment of 3,3'-diselenodipropionic acid augments cell kill by modulating DNA repair and cell migration pathways in A549 cells

Aim of the present study was to test whether ionizing radiation (IR) treatment along with 3,3'-diselenodipropionic acid (DSePA), a redox active organodiselenide achieved better tumor control by suppressing the growth and migration of lung cancer cells. The results indicated that post-IR (2 Gy) treatment of DSePA (5 μM) led to a significantly higher cell death as compared to that of DSePA and IR treatments separately. Importantly, combinatorial treatment also showed reduction in the proportion of cancer stem cells and the clonogenic survival of A549 cells. The mechanistic studies indicated that combinatorial treatment although exhibited reductive environment (marked by decrease in ROS and increase of GSH/GSSG) at early time points (2-6 h postradiation), slowed DNA repair, inhibited epithelial-mesenchymal transition (EMT)/cell migration and induced significant level of apoptosis. DSePA mediated suppression of ATM/DNAPKs/p53 (DNA damage response signaling) and Akt/G-CSF (EMT) pathways appeared to be the major mechanism responsible for its radio-modulating activity. Finally, the combined treatment of IR (2 Gy × 4) and DSePA (0.1-0.25 mg/kg body weight daily through oral gavage) showed a significantly higher tumor suppression of the A549 xenograft as compared to that of DSePA and IR treatments separately in the mouse model. In conclusion, post-IR treatment of DSePA augmented cell kill by inhibiting DNA repair and cell migration in A549 cells.

Cancer in pathologically confirmed multiple system atrophy

PURPOSE

The aim of this study was to assess whether cancer occurs with increased frequency in multiple system atrophy (MSA). The pathological hallmark of MSA is glial cytoplasmic inclusions containing aggregated α-synuclein, and the related protein γ-synuclein correlates with invasive cancer. We investigated whether these two disorders are associated clinically.

METHODS

Medical records of 320 patients with pathologically confirmed MSA seen between 1998 and 2022 were reviewed. After excluding those with insufficient medical histories, the remaining 269 and an equal number of controls matched for age and sex were queried for personal and family histories of cancer recorded on standardized questionnaires and in clinical histories. Additionally, age-adjusted rates of breast cancer were compared with US population incidence data.

RESULTS

Of 269 cases in each group, 37 with MSA versus 45 of controls had a personal history of cancer. Reported cases of cancer in parents were 97 versus 104 and in siblings 31 versus 44 for MSA and controls, respectively. Of 134 female cases in each group, 14 MSA versus 10 controls had a personal history of breast cancer. The age-adjusted rate of breast cancer in MSA was 0.83%, as compared with 0.67% in controls and 2.0% in the US population. All comparisons were nonsignificant.

CONCLUSION

The evidence from this retrospective cohort found no significant clinical association of MSA with breast cancer or other cancers. These results do not exclude the possibility that knowledge about synuclein pathology at the molecular level in cancer may lead to future discoveries and potential therapeutic targets for MSA.

Intragenic β-synuclein rearrangements in malignancy

The synuclein family, consisting of α-, β-, and γ-synuclein, is primarily expressed in neurons. Mutations of α- and β-synuclein have been linked to Parkinson's disease and dementia with Lewy bodies, respectively. Recent studies have shown that synucleins are upregulated in various tumors, including breast, ovarian, meningioma, and melanoma, and high synuclein expression is associated with poor prognosis and drug resistance. We report a novel rearrangement of β-synuclein in a pediatric T-cell acute lymphoblastic leukemia (T-ALL) case, where β-synuclein (SNCB) is fused in-frame with ETS variant transcription factor 6 (ETV6), a gene frequently rearranged in acute leukemia including acute myeloid leukemia (AML), B-cell acute lymphoblastic leukemia (B-ALL), and T-ALL. An additional case of β-synuclein rearrangement was identified in a squamous cell carcinoma of the lung through analysis of the public TCGA database. Both rearrangements involve the C-terminal of β-synuclein. Since β-synuclein shares extensive amino acid similarities with α-synuclein and α-synuclein binds to 14-3-3, an important regulator of apoptosis, the rearranged β-synuclein may contribute to tumorigenesis by deregulating apoptosis. In addition, overexpression of synucleins has been shown to increase cell proliferation, suggesting that the rearranged β-synuclein may also deregulate the cell cycle.

Differentially Expressed Genes Induced by Erythropoietin Receptor Overexpression in Rat Mammary Adenocarcinoma RAMA 37-28 Cells

The erythropoietin receptor (EPOR) is a transmembrane type I receptor with an essential role in the proliferation and differentiation of erythroid progenitors. Besides its function during erythropoiesis, EPOR is expressed and has protective effect in various non-hematopoietic tissues, including tumors. Currently, the advantageous aspect of EPOR related to different cellular events is still under scientific investigation. Besides its well-known effect on cell proliferation, apoptosis and differentiation, our integrative functional study revealed its possible associations with metabolic processes, transport of small molecules, signal transduction and tumorigenesis. Comparative transcriptome analysis (RNA-seq) identified 233 differentially expressed genes (DEGs) in EPOR overexpressed RAMA 37-28 cells compared to parental RAMA 37 cells, whereas 145 genes were downregulated and 88 upregulated. Of these, for example, GPC4, RAP2C, STK26, ZFP955A, KIT, GAS6, PTPRF and CXCR4 were downregulated and CDH13, NR0B1, OCM2, GPM6B, TM7SF3, PARVB, VEGFD and STAT5A were upregulated. Surprisingly, two ephrin receptors, EPHA4 and EPHB3, and EFNB1 ligand were found to be upregulated as well. Our study is the first demonstrating robust differentially expressed genes evoked by simple EPOR overexpression without the addition of erythropoietin ligand in a manner which remains to be elucidated.

Cancer Cells Enter an Adaptive Persistence to Survive Radiotherapy and Repopulate Tumor

Repopulation of residual tumor cells impedes curative radiotherapy, yet the mechanism is not fully understood. It is recently appreciated that cancer cells adopt a transient persistence to survive the stress of chemo- or targeted therapy and facilitate eventual relapse. Here, it is shown that cancer cells likewise enter a "radiation-tolerant persister" (RTP) state to evade radiation pressure in vitro and in vivo. RTP cells are characterized by enlarged cell size with complex karyotype, activated type I interferon pathway and two gene patterns represented by CST3 and SNCG. RTP cells have the potential to regenerate progenies via viral budding-like division, and type I interferon-mediated antiviral signaling impaired progeny production. Depleting CST3 or SNCG does not attenuate the formation of RTP cells, but can suppress RTP cells budding with impaired tumor repopulation. Interestingly, progeny cells produced by RTP cells actively lose their aberrant chromosomal fragments and gradually recover back to a chromosomal constitution similar to their unirradiated parental cells. Collectively, this study reveals a novel mechanism of tumor repopulation, i.e., cancer cell populations employ a reversible radiation-persistence by poly- and de-polyploidization to survive radiotherapy and repopulate the tumor, providing a new therapeutic concept to improve outcome of patients receiving radiotherapy.

The Synucleins and the Astrocyte

Synucleins consist of three proteins exclusively expressed in vertebrates. α-Synuclein (αS) has been identified as the main proteinaceous aggregate in Lewy bodies, a pathological hallmark of many neurodegenerative diseases. Less is understood about β-synuclein (βS) and γ-synuclein (γS), although it is known βS can interact with αS in vivo to inhibit aggregation. Likewise, both γS and βS can inhibit αS's propensity to aggregate in vitro. In the central nervous system, βS and αS, and to a lesser extent γS, are highly expressed in the neural presynaptic terminal, although they are not strictly located there, and emerging data have shown a more complex expression profile. Synapse loss and astrocyte atrophy are early aspects of degenerative diseases of the brain and correlate with disease progression. Synucleins appear to be involved in synaptic transmission, and astrocytes coordinate and organize synaptic function, with excess αS degraded by astrocytes and microglia adjacent to the synapse. βS and γS have also been observed in the astrocyte and may provide beneficial roles. The astrocytic responsibility for degradation of αS as well as emerging evidence on possible astrocytic functions of βS and γS, warrant closer inspection on astrocyte-synuclein interactions at the synapse.

Upregulation of Synuclein-γ and Snai1 Contributes to Poor Clinical Prognosis in Oral Squamous Cell Carcinoma Patients

Synuclein-γ (SNCG) and Snai1 play an important role in the occurrence and development of different types of malignant tumors. However, the association between SNCG and Snai1 and the effect of their combination on oral squamous cell carcinoma (OSCC) are unknown. The purpose of this study was to assess the expression of SNCG and Snai1 in OSCC tissues and their role in the genesis, development, diagnosis, and prognosis of OSCC. In this study, we first analyzed the Gene Expression Omnibus (GEO) database to determine the expression of SNCG and Snai1 in OSCC. And we also evaluated the correlation between the expression of SNCG and Snai1 and clinical pathological parameters in OSCC from The Cancer Genome Atlas (TCGA) database. Then, the expression of SNCG and Snai1 in OSCC and its adjacent tissues in our experimental cohort were detected by qRT-PCR, Western blot, and immunohistochemistry, and the relationship between their expression and clinical pathological parameters were analyzed. At the same time, the correlation between the expression of SNCG and Snai1 was analyzed from the TCGA, GEO database, and our experimental cohort. Next, the ROC curves were constructed to explore the diagnostic value of SNCG and Snai1 in OSCC. Finally, the survival curves were drawn, and the univariate and multivariate Cox regression analyses were performed to determine the prognostic value of SNCG and Snai1 in OSCC. The study found that SNCG and Snai1 were highly expressed in OSCC tissues. The expression of SNCG was related to the differentiation of OSCC, while that of Snai1 was related to the T stage, lymph node metastasis, clinical stage, and differentiation. Besides, the expression of SNCG in OSCC was positively correlated with that of Snai1. In addition, we also found that SNCG and Snai1 could well distinguish OSCC patients from normal people; especially, the combined diagnosis of SNCG and Snai1 had a better effect, with a specificity up to 96.67%. Moreover, SNCG-negative/Snai1-negative OSCC patients had the best prognosis. Multivariate analysis displayed that SNCG-positive expression was an independent risk factor for prognosis in OSCC patients. The results of this study strongly suggested that SNCG and Snai1 might have a cooperative effect in the occurrence and development of OSCC. They may become new markers for the diagnosis and prognosis of OSCC.

Prognostic significance of SNCA and its methylation in bladder cancer

Background

The epidemiological investigation of different cancer types in the global population has reported a decreased risk of bladder cancer (BLCA) in Parkinson’s diseases (PD). SNCA a critical gene in PD pathology have been reported involved in tumorigenesis recently. However, the role of SNCA in BLCA remains unclear. This study aimed to explore the potential value of SNCA as a prognostic diagnostic molecular biomarker in BLCA.

Methods

In this study, we explored the expression pattern, prognostic value and promoter methylation level of SNCA in BLCA by GEPIA2, UALCAN, TCGA, GENT2, GEO and c-BioPortal database. Then, we used LinkedOmics database to obtain the co-expression genes of SNCA for further study by WGCNA. We further investigated the correlations between SNCA expression and six main types of immune cell infiltrations and immune signatures by TIMER. Finally, BLCA cell lines treated with 5-Aza-CdR were used to explore the correlation between increased methylation and downregulated mRNA expression.

Results

SNCA was downregulated in tumor tissues in TCGA-BLCA, GENT2 and GEO, which was validated in our cohort by qRT-PCR and immunohistochemistry. SNCA was confirmed as an independent predictor of poor overall survival (OS). LinkedOmics analysis suggested that SNCA regulates cell adhesion molecules, cytokine–cytokine receptor interaction, and complement and coagulation cascades. Twenty-two co-expression gene modules were constructed by WGCNA, and most of them were significantly associated with OS and disease-free survival (DFS). Six key genes (CNTN1, DACT3, MYLK1, PDE2A, RBM24, and ST6GALNAC3) screened also significantly correlated with prognosis. There were significant correlations between SNCA expression and immune infiltrations, especially T cell, suggesting that immune infiltration was one of the reasons for the influence of SNCA on prognosis in BLCA. Analysis by ULACAN and c-BioPortal showed that the promoter methylation of SNCA negatively correlated with its mRNA level. Furthermore, BLCA cell treatment with 5-Aza-CdR revealed that SNCA expression levels were upregulated with decreased methylation.

Conclusion

Our research showed that SNCA was downregulated in BLCA and negatively correlation with DNA methylation. High SNCA expression was confirmed as an independent risk for prognosis. SNCA probably plays an important role in the infiltration of immune cells, especially with T cells. Thus, SNCA may be a promising prognostic biomarker in BLCA patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09411-9.

Adiponectin paradox as a therapeutic target of the cancer evolvability in aging

Recent study suggests that protofibril-formation of amyloidogenic proteins (APs) might be involved in evolvability, an epigenetic inheritance of multiple stresses, in various biological systems. In cancer, evolvability of multiple APs, such as p53, γ-synuclein and the members of the calcitonin family of peptides, might be involved in various features, including increased cell proliferation, metastasis and medical treatment resistance. In this context, the objective of this paper is to explore the potential therapeutic benefits of reduced APs evolvability against cancer. Notably, the same APs are involved in the pathogenesis of neurodegenerative disease and cancer. Given the unsatisfactory outcomes of recent clinical trial of Aβ immunotherapy in Alzheimer's disease, it is possible that suppressing the aggregation of individual APs might also be not effective in cancer. As such, we highlight the adiponectin (APN) paradox that might be positioned upstream of AP aggregation in both neurodegenerative disease and cancer, as a common therapeutic target in both disease types. Provided that the APN paradox due to APN resistance under the diabetic conditions might promote AP aggregation, suppressing the APN paradox combined with antidiabetic treatments might be effective for the therapy of both neurodegenerative disease and cancer.

SNCG promotes the progression and metastasis of high-grade serous ovarian cancer via targeting the PI3K/AKT signaling pathway

Background

The poor prognosis of patients with ovarian cancer is mainly due to cancer progression. γ-Synuclein (SNCG) has reported as a critical player in cancer metastasis. However, its biological roles and mechanism are yet incompletely understood in ovarian cancer, especially in high-grade serous ovarian cancer (HGSOC).

Methods

This is a retrospective study of 312 patients with ovarian cancer at a single center between 2006 and 2016. Ovarian cancer tissues were stained by immunohistochemistry to analyze the relationship between SNCG expression and clinicopathologic factors. The clinical outcomes versus SNCG expression level were evaluated by Kaplan–Meier method and multiple Cox regression analysis. Next, systematical functional experiments were given to examine the proliferation and metastatic abilities of SNCG both in vitro and in vivo using loss- and gain- of function approaches. Furthermore, the mechanisms of SNCG overexpression were examined by human phospho-kinase array kit and western blot analysis.

Results

Clinically, the expression of SNCG was significantly upregulated in ovarian cancer compared with the borderline and benign tumor, normal ovary, and fallopian tube. Notably, the high level of SNCG correlated with high-risk clinicopathologic features and showed poor survival for patients with HGSOC, indicating an independent prognostic factor for these patients. Functionally, we observed that overexpression of SNCG promoted cell proliferation, tumor formation, migration, and invasion both in vitro and in vivo. Mechanistically, we identified that SNCG promoted cancer cell metastasis through activating the PI3K/AKT signaling pathway.

Conclusions

Our results reveal SNCG up-regulation contributes to the poor clinical outcome of patients with HGSOC and highlight the metastasis-promoting function of SNCG via activating the PI3K/Akt signaling pathway in HGSOC.

A Network-Based Method for Mechanistic Investigation and Neuroprotective Effect on Post-treatment of Senkyunolid-H Against Cerebral Ischemic Stroke in Mouse

Senkyunolide-H (SEH), a major bioactive compound extracted from Ligusticum chuanxiong, has been reported to be effective in preventing cerebral ischemic stroke (CIS). In this study, we employed network pharmacology to reveal potential mechanism of SEH against CIS on a system level and confirmed the therapeutic effects of SEH on CIS by models of cerebral ischemia-reperfusion in vivo and in vitro. Through protein-protein interaction networks construction of SEH- and CIS-related targets, a total of 62 key targets were obtained by screening topological indices and analyzed for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment. Gene Ontology analysis indicated that SEH might have a role in treating CIS via regulating some biological processes including regulation of transcription from RNA polymerase II promoter, epidermal growth factor receptor signaling pathway, phosphatidylinositol-mediated signaling, and some molecular function, such as transcription factor and protein phosphatase binding and nitric oxide synthase regulator activity. Meanwhile, the Kyoto Encyclopedia of Genes and Genomes analysis showed that phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway was significantly enriched. In addition, our result showed that SEH posttreatment significantly decreased the neurological scores, infarct volume, and neuronal death in the middle cerebral artery occlusion mice. Moreover, the PI3K/Akt/nuclear factor kappa B signaling pathway was activated by intragastric administration of 40 mg/kg SEH, as verified by Western blot. In vitro, treatment of PC12 cells with 100 μM SEH markedly reduced cell death induced by oxygen-glucose deprivation through the activation of PI3K/Akt/nuclear factor kappa B pathway, and the therapeutic effect of SEH was obviously inhibited by 10 μM LY294002. In summary, these results suggested that SEH carries a therapeutic potential in CIS involving multiple targets and pathways, and the most crucial mechanism might be through the activation of PI3K/Akt/nuclear factor kappa B (NF-κB) signaling pathway to inhibit inflammatory factor releases and increase the antiapoptosis capacity. Our study furnishes the future traditional Chinese medicine research with a network pharmacology framework.

Neuroprotective Effects of Gabapentin Against Cerebral Ischemia Reperfusion-Induced Neuronal Autophagic Injury via Regulation of the PI3K/Akt/mTOR Signaling Pathways

Gabapentin (GBP), an analgesic, adjunct antiepileptic, and migraine prophylactic drug, reduces neuronal injury induced by cerebral ischemia reperfusion (IR). However, the underlying biological molecular mechanism of GBP neuroprotection is not clear. In this study, we confirmed that dose-dependent (75 and 150 mg/kg) GBP treatment could significantly reduce IR-induced neuronal death. IR-induced neuronal death was inhibited by pretreatment with 150 mg/kg GBP in a middle cerebral artery occlusion rat model. In addition, 150 mg/kg GBP treatment remarkably promoted the levels of antioxidants and reduced the autophagy of neurons in the infarct penumbra. Moreover, the phosphoinositide-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway was activated by pretreatment with 150 mg/kg GBP, as detected by Western blot analyses. In vitro, pretreatment of PC12 cells with 450 µM GBP significantly reduced cell death induced by oxygen-glucose deprivation, increased antioxidant function, and reduced the levels of autophagy and reactive oxygen species via activation of the PI3K/Akt/mTOR pathway. This neuroprotection by GBP was inhibited significantly by 10 µM LY294002. In summary, dose-dependent pretreatment with GBP protected against cerebral IR injury via activation of the PI3K/Akt/mTOR pathway, which provided a neuroprotective function to inhibit oxidative stress-related neuronal autophagy.

Twiner: correlation-based regularization for identifying common cancer gene signatures

Background

Breast and prostate cancers are typical examples of hormone-dependent cancers, showing remarkable similarities at the hormone-related signaling pathways level, and exhibiting a high tropism to bone. While the identification of genes playing a specific role in each cancer type brings invaluable insights for gene therapy research by targeting disease-specific cell functions not accounted so far, identifying a common gene signature to breast and prostate cancers could unravel new targets to tackle shared hormone-dependent disease features, like bone relapse. This would potentially allow the development of new targeted therapies directed to genes regulating both cancer types, with a consequent positive impact in cancer management and health economics.

Results

We address the challenge of extracting gene signatures from transcriptomic data of prostate adenocarcinoma (PRAD) and breast invasive carcinoma (BRCA) samples, particularly estrogen positive (ER+), and androgen positive (AR+) triple-negative breast cancer (TNBC), using sparse logistic regression. The introduction of gene network information based on the distances between BRCA and PRAD correlation matrices is investigated, through the proposed twin networks recovery (twiner) penalty, as a strategy to ensure similarly correlated gene features in two diseases to be less penalized during the feature selection procedure.

Conclusions

Our analysis led to the identification of genes that show a similar correlation pattern in BRCA and PRAD transcriptomic data, and are selected as key players in the classification of breast and prostate samples into ER+ BRCA/AR+ TNBC/PRAD tumor and normal tissues, and also associated with survival time distributions. The results obtained are supported by the literature and are expected to unveil the similarities between the diseases, disclose common disease biomarkers, and help in the definition of new strategies for more effective therapies.