Circular RNAs in EMT-driven metastasis regulation: modulation of cancer cell plasticity, tumorigenesis and therapy resistance.

The non-coding RNAs comprise a large part of human genome lack of capacity in encoding functional proteins. Among various members of non-coding RNAs, the circular RNAs (circRNAs) have been of importance in the pathogenesis of human diseases, especially cancer. The circRNAs have a unique closed loop structure and due to their stability, they are potential diagnostic and prognostic factors in cancer. The increasing evidences have highlighted the role of circRNAs in the modulation of proliferation and metastasis of cancer cells. On the other hand, metastasis has been responsible for up to 90% of cancer-related deaths in patients, requiring more investigation regarding the underlying mechanisms modulating this mechanism. EMT enhances metastasis and invasion of tumor cells, and can trigger resistance to therapy. The cells demonstrate dynamic changes during EMT including transformation from epithelial phenotype into mesenchymal phenotype and increase in N-cadherin and vimentin levels. The process of EMT is reversible and its reprogramming can disrupt the progression of tumor cells. The aim of current review is to understanding the interaction of circRNAs and EMT in human cancers and such interaction is beyond the regulation of cancer metastasis and can affect the response of tumor cells to chemotherapy and radiotherapy. The onco-suppressor circRNAs inhibit EMT, while the tumor-promoting circRNAs mediate EMT for acceleration of carcinogenesis. Moreover, the EMT-inducing transcription factors can be controlled by circRNAs in different human tumors.

Nanoparticles in tumor microenvironment remodeling and cancer immunotherapy.

Cancer immunotherapy and vaccine development have significantly improved the fight against cancers. Despite these advancements, challenges remain, particularly in the clinical delivery of immunomodulatory compounds. The tumor microenvironment (TME), comprising macrophages, fibroblasts, and immune cells, plays a crucial role in immune response modulation. Nanoparticles, engineered to reshape the TME, have shown promising results in enhancing immunotherapy by facilitating targeted delivery and immune modulation. These nanoparticles can suppress fibroblast activation, promote M1 macrophage polarization, aid dendritic cell maturation, and encourage T cell infiltration. Biomimetic nanoparticles further enhance immunotherapy by increasing the internalization of immunomodulatory agents in immune cells such as dendritic cells. Moreover, exosomes, whether naturally secreted by cells in the body or bioengineered, have been explored to regulate the TME and immune-related cells to affect cancer immunotherapy. Stimuli-responsive nanocarriers, activated by pH, redox, and light conditions, exhibit the potential to accelerate immunotherapy. The co-application of nanoparticles with immune checkpoint inhibitors is an emerging strategy to boost anti-tumor immunity. With their ability to induce long-term immunity, nanoarchitectures are promising structures in vaccine development. This review underscores the critical role of nanoparticles in overcoming current challenges and driving the advancement of cancer immunotherapy and TME modification.

Investigating autophagy and intricate cellular mechanisms in hepatocellular carcinoma: Emphasis on cell death mechanism crosstalk.

Hepatocellular carcinoma (HCC) stands as a formidable global health challenge due to its prevalence, marked by high mortality and morbidity rates. This cancer type exhibits a multifaceted etiology, prominently linked to viral infections, non-alcoholic fatty liver disease, and genomic mutations. The inherent heterogeneity of HCC, coupled with its proclivity for developing drug resistance, presents formidable obstacles to effective therapeutic interventions. Autophagy, a fundamental catabolic process, plays a pivotal role in maintaining cellular homeostasis, responding to stressors such as nutrient deprivation. In the context of HCC, tumor cells exploit autophagy, either augmenting or impeding its activity, thereby influencing tumorigenesis. This comprehensive review underscores the dualistic role of autophagy in HCC, acting as both a pro-survival and pro-death mechanism, impacting the trajectory of tumorigenesis. The anti-carcinogenic potential of autophagy is evident in its ability to enhance apoptosis and ferroptosis in HCC cells. Pertinently, dysregulated autophagy fosters drug resistance in the carcinogenic context. Both genomic and epigenetic factors can regulate autophagy in HCC progression. Recognizing the paramount importance of autophagy in HCC progression, this review introduces pharmacological compounds capable of modulating autophagy-either inducing or inhibiting it, as promising avenues in HCC therapy.

Cancer stem cell-mediated drug resistance: A comprehensive gene expression profile analysis in breast cancer.

Breast cancer is the most frequently diagnosed malignancy in women and a major public health concern. In the current report, differential expression of the breast cancer resistance promoting genes with a focus on breast cancer stem cell related elements as well as the correlation of their mRNAs with various clinicopathologic characteristics, including molecular subtypes, tumor grade/stage, and methylation status, have been investigated using METABRIC and TCGA datasets. To achieve this goal, we downloaded gene expression data of breast cancer patients from TCGA and METABRIC. Then, statistical analyses were used to assess the correlation between the expression levels of stem cell related drug resistant genes and methylation status, tumor grades, various molecular subtypes, and some cancer hallmark gene sets such as immune evasion, metastasis, and angiogenesis. According to the results of this study, a number of stem cell related drug resistant genes are deregulated in breast cancer patients. Furthermore, we observe negative correlations between methylation of resistance genes and mRNA expression. There is a significant difference in the expression of resistance-promoting genes between different molecular subtypes. As mRNA expression and DNA methylation are clearly related, DNA methylation might be a mechanism that regulates these genes in breast cancer cells. As indicated by the differential expression of resistance-promoting genes among various breast cancer molecular subtypes, these genes may function differently in different subtypes of breast cancer. In conclusion, significant deregulation of resistance-promoting factors indicates that these genes may play a significant role in the development of breast cancer.

Genomic and Personalized Medicine Perspective in Genetic Generalized Epilepsy.

The genetic generalized epilepsies (GGEs) are a set of disorders presenting with generalized seizures, in addition to general spike-wave activity. The present study aims to investigate the clinical manifestations and genetic origin of generalized tonicclonic seizures and the subgroups of GGEs, including childhood absence epilepsy (CAE), juvenile absence epilepsy, and juvenile myoclonic epilepsy (JME). Information compiled from genome-wide association studies (GWASs) in the EPICure project revealed associations with many genes. Besides, copy number variant (CNV) discoveries have been the most inspiring turning point of epilepsy genetic research. This phenomenon could give us an idea about microdeletions/microduplications as genetic variants throughout the whole genome. Nowadays, next-generation sequencing (NGS) approaches support neurogeneticists to unravel the predisposed putative variants in GGE to establish a better diagnosis. Consequently, previous experiments supply data for antiepileptic drugs (AEDs) to test susceptible variants, which influence the response to drugs. As a final point, all these data should provide the current GGE patients with better genetic counseling and follow-up services.

Gene Silencing of TGFßRII Can Inhibit Glioblastoma Cell Growth

Objective: Glioblastoma (GBM) is the most malignant and aggressive type of glioma, associated with a high rate of mortality. The transforming growth factor-ß receptor II (TGFß RII) is involved in glioma initiation and progression. On the other hand, TGFß RII silencing is critical to the inhibition of GBM. Therefore, we aimed to determine the effects of specific TGFß RII siRNA on the survival of U-373MG cells. Methods: TGFß RII siRNA was transfected, and qRT-PCR was performed to examine TGFß RII mRNA expression. Cell survival was determined using colorimetric MTT assay, and platelet-derived growth factor-BB (PDGF-BB) level was measured in the culture supernatant using ELISA assay. Result: Our findings indicated that specific siRNAs could dose-dependently suppress TGFß RII mRNA expression after 48 hours. In addition, treatment with TGFß RII siRNA significantly reduced tumor cell survival and decreased the amount of PDGF-BB protein in the cell culture supernatant. Conclusion: Our results suggest that TGFß RII silencing can be a promising complementary treatment for glioma.

Association of the epidermal growth factor gene +61A>G polymorphism with hepatocellular carcinoma in an Iranian population.

AIM: The aim of this study was to address the association of the EGF gene +61A/G polymorphisms and HCC susceptibility in an Iranian population. BACKGROUND: The association of epidermal growth factor (EGF) gene +61A/G polymorphism (rs4444903) and hepatocellular carcinoma (HCC) has been investigated in several populations. However, the findings are controversial. METHODS: A total of 40 unrelated HCC patients and 106 healthy individuals were enrolled in this study. Genomic DNA of HCC patients was extracted from formalin-fixed, paraffin-embedded samples using CinnaPure DNA kit according to manufacturer's instructions. Genomic DNA of healthy individuals, also, was extracted from peripheral blood cells using the boiling method. The rs4444903 (A/G) polymorphism was genotyped using the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. RESULTS: Significant association was found for the EGF +61A allele and HCC risk [OR = 1.72, 95% CI (1.02 - 2.90), P value = 0.04]. Also, significant association was observed for the EGF +61A/G genotypes and HCC risk under codominant and dominant models by SNPStats software analysis. CONCLUSION: Our findings suggest that the EGF gene +61A/G polymorphism (rs4444903) might be a risk factor for susceptibility to HCC in Iranian population. However, further studies using more samples are needed.