Cell Cycle Function Research Articles

Potential Common Molecular Mechanisms Between Periodontitis and Hepatocellular Carcinoma: A Bioinformatic Analysis and Validation.

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has a poor prognosis. Periodontitis, or tooth loss, is considered to be related to hepatocarcinogenesis and its poor prognosis. This study aimed to explore potential associations and cross-talk mechanisms between periodontitis and HCC. Periodontitis and HCC microarray datasets were acquired from the Gene Expression Omnibus (GEO) database and were analyzed to obtain differentially expressed (DE) lncRNAs, miRNAs and mRNAs. Functional enrichment analysis was used to detect the functions of these mRNAs. Then, a ceRNA network of periodontitis-related HCC was constructed. Least absolute shrinkage and selection operator (LASSO) regression, random forest algorithm, and support vector machine-recursive feature elimination (SVM-RFE) were performed to explore the diagnostic significance of mRNAs in periodontitis-related HCC. Cox regression analyses were conducted to screen mRNAs with prognostic significance in HCC. Quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC) were conducted to validate the expression of these mRNAs in HCC tissues. A ceRNA network was constructed. Functional enrichment analysis indicated that the network is associated with immune and inflammatory responses, the cell cycle and liver metabolic function. LASSO, random forest algorithm and SVM-RFE showed the diagnostic significance of DE mRNAs in HCC. Cox regression analyses revealed that MSH2, GRAMD1C and CTHRC1 have prognostic significance for HCC, and qRT-PCR and IHC validated this finding. Periodontitis may affect the occurrence of HCC by changing the immune and inflammatory response, the cell cycle and liver metabolic function. MSH2, GRAMD1C and CTHRC1 are potential prognostic biomarkers for HCC.

GINS2 regulates epithelial mesenchymal transformation and cell cycle in endometrial carcinoma by stimulating ERK/MAPK signaling

Endometrial cancer (EC) is one of the three main gynecological cancers. Identifying new therapeutic targets and further elucidating the molecular mechanisms of EC tumorigenesis have important implications for women’s health. The Go-Ichi-Ni-San (GINS) family, which includes four subunits (GINS1–4), has specific functions in DNA replication and cell cycle. The Cancer Genome Atlas (TCGA) data showed that GINS2 transcription level is upregulated in endometrial cancer tissue. However, the possible role of GINS2 in EC progression is still unknown. Herein, we explored the role of GINS2 in EC. We noticed that GINS2 was overexpressed in EC cells. GINS2 knockdown suppressed the proliferation of EC cells and induced cell cycle arrest. We further noticed that GINS2 knockdown restrained the Epithelial mesenchymal transformation (EMT) of EC cells. Mechanically, its downregulation suppressed the extracellular regulated protein kinase (ERK)/Microtubule-Associated Protein Kinase (MAPK) pathway, thereby suppressing EC progression. Thus, GINS2 has the potential to act as a therapeutic target for EC.

Sirtuins: Key players in obesity-associated adipose tissue remodeling.

Obesity, a complex disease involving an excessive amount of body fat and a major threat to public health all over the world, is the determining factor of the onset and development of metabolic disorders, including type 2 diabetes, cardiovascular diseases, and non-alcoholic fatty liver disease. Long-term overnutrition results in excessive expansion and dysfunction of adipose tissue, inflammatory responses and over-accumulation of extracellular matrix in adipose tissue, and ectopic lipid deposit in other organs, termed adipose tissue remodeling. The mammalian Sirtuins (SIRT1-7) are a family of conserved NAD+-dependent protein deacetylases. Mounting evidence has disclosed that Sirtuins and their prominent substrates participate in a variety of physiological and pathological processes, including cell cycle regulation, mitochondrial biogenesis and function, glucose and lipid metabolism, insulin action, inflammatory responses, and energy homeostasis. In this review, we provided up-to-date and comprehensive knowledge about the roles of Sirtuins in adipose tissue remodeling, focusing on the fate of adipocytes, lipid mobilization, adipose tissue inflammation and fibrosis, and browning of adipose tissue, and we summarized the clinical trials of Sirtuin activators and inhibitors in treating metabolic diseases, which might shed light on new therapeutic strategies for obesity and its associated metabolic diseases.

Construction of a Colorectal Cancer Prognostic Risk Model and Screening of Prognostic Risk Genes Using Machine-Learning Algorithms.

This study is aimed at constructing a prognostic risk model for colorectal cancer (CRC) using machine-learning algorithms to provide accurate staging and screening of credible prognostic risk genes. We extracted CRC data from GSE126092 and GSE156355 of the Gene Expression Omnibus (GEO) database and datasets from TCGA to analyze the differentially expressed genes (DEGs) using bioinformatics analysis. Among the 330 shared DEGs related to CRC prognosis, we divided the analysis period into different phases and applied univariate COX regression, LASSO, and multivariate COX regression analysis. GO analysis and KEGG analysis revealed that the functions of these DEGs were primarily focused on cell cycle, DNA replication, cell mitosis, and other related functions, and this confirmed our results from a biological perspective. Finally, a prognostic risk model for CRC based on the CHGA, CLU, PLK1, AXIN2, NR3C2, IL17RB, GCG, and AJUBA genes was constructed, and the risk score enabled us to predict the prognosis for CRC. To obtain a comprehensive and accurate model, we used both internal and external evaluations, and the model was able to correctly differentiate patients with CRC into a high-risk group with poor prognosis and a low-risk group with good prognosis. The AUC values of the 3-, 5-, and 10-year survival ROC curves were 0.715, 0.721, and 0.777, respectively, according to the internal evaluation, and the AUC values were 0.606, 0.698, and 0.608, respectively, for the external evaluation using GSE39582 from the GEO database. We determined that CLU, PLK1, and IL17RB could be considered to be independent prognostic factors for CRC with significantly different expression (P < 0.05). Using machine-learning methods, a prognostic risk model comprised of eight genes was constructed. Not only does this model provide improved treatment guidance, but it also provides a novel perspective for analyzing survival conditions at a deeper biological level.

Neutrophil-to-lymphocyte ratio as a potential biomarker in predicting influenza susceptibility.

BackgroundHuman population exposed to influenza viruses exhibited wide variation in susceptibility. The ratio of neutrophils to lymphocytes (NLR) has been examined to be a marker of systemic inflammation. We sought to investigate the relationship between influenza susceptibility and the NLR taken before influenza virus infection.MethodsWe investigated blood samples from five independent influenza challenge cohorts prior to influenza inoculation at the cellular level by using digital cytometry. We used multi-cohort gene expression analysis to compare the NLR between the symptomatic infected (SI) and asymptomatic uninfected (AU) subjects. We then used a network analysis approach to identify host factors associated with NLR and influenza susceptibility.ResultsThe baseline NLR was significantly higher in the SI group in both discovery and validation cohorts. The NLR achieved an AUC of 0.724 on the H3N2 data, and 0.736 on the H1N1 data in predicting influenza susceptibility. We identified four key modules that were not only significantly correlated with the baseline NLR, but also differentially expressed between the SI and AU groups. Genes within these four modules were enriched in pathways involved in B cell-mediated immune responses, cellular metabolism, cell cycle, and signal transduction, respectively.ConclusionsThis study identified the NLR as a potential biomarker for predicting disease susceptibility to symptomatic influenza. An elevated NLR was detected in susceptible hosts, who may have defects in B cell-mediated immunity or impaired function in cellular metabolism, cell cycle or signal transduction. Our work can serve as a comparative model to provide insights into the COVID-19 susceptibility.

Engrailed homeobox 1 transcriptional regulation of COL22A1 inhibits nasopharyngeal carcinoma cell senescence through the G1/S phase arrest.

EN1 is well known as a transcription factor in other tumours, but its role in NPC is unclear. In this study, we first used bioinformatics to analyse GEO data to obtain the differentially expressed gene EN1, and subsequently verified that EN1 was highly expressed in nasopharyngeal carcinoma cells by tissue microarrays as well as cell lines. Further, we down-regulated the expression of EN1 in cells for RNA sequencing. The analysis of sequencing results using KEGG and GO revealed significant changes in cell proliferation and cycle function after downregulation of EN1. Meanwhile, we found that cells underwent senescence after inhibition of EN1 under electron microscopy and the SA-β-gal assays. Based on the sequencing results, we verified that EN1 can promote the proliferation and cycle of NPC cells in cell function experiments and animal experiments. To investigate how EN1 affects cell senescence, we found that EN1 transcriptional regulation of COL22A1 regulated cell proliferation and cycle via CDK4/6-cyclin D1-Rb signalling pathway by dual luciferase reporter, Immunoblotting and rescue experiment. Accordingly, we uncovered that EN1 could serve as a target for the regulation of senescence in NPC.

Cross-talk of four types of RNA modification proteins with adenosine reveals the landscape of multivariate prognostic patterns in breast cancer.

Background: Breast cancer (BC) is the most common malignant tumour, and its heterogeneity is one of its major characteristics. N6-methyladenosine (m6A), N1-methyladenosine (m1A), alternative polyadenylation (APA), and adenosine-to-inosine (A-to-I) RNA editing constitute the four most common adenosine-associated RNA modifications and represent the most typical and critical forms of epigenetic regulation contributing to the immunoinflammatory response, tumorigenesis and tumour heterogeneity. However, the cross-talk and potential combined profiles of these RNA-modified proteins (RMPs) in multivariate prognostic patterns of BC remain unknown. Methods: A total of 48 published RMPs were analysed and found to display significant expression alterations and genomic mutation rates between tumour and normal tissues in the TCGA-BRCA cohort. Data from 4188 BC patients with clinical outcomes were downloaded from the Gene Expression Omnibus (GEO), the Cancer Genome Atlas (TCGA), and the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC), normalized and merged into one cohort. The prognostic value and interconnections of these RMPs were also studied. The four prognosis-related genes (PRGs) with the greatest prognostic value were then selected to construct diverse RMP-associated prognostic models through univariate Cox (uniCox) regression analysis, differential expression analysis, Least absolute shrinkage and selection operator (LASSO) regression and multivariate Cox (multiCox) regression. Alterations in biological functional pathways, genomic mutations, immune infiltrations, RNAss scores and drug sensitivities among different models, as well as their prognostic value, were then explored. Results: Utilizing a large number of samples and a comprehensive set of genes contributing to adenosine-associated RNA modification, our study revealed the joint potential bio-functions and underlying features of these diverse RMPs and provided effective models (PRG clusters, gene clusters and the risk model) for predicting the clinical outcomes of BC. The individuals with higher risk scores showed poor prognoses, cell cycle function enrichment, upregulation of stemness scores, higher tumour mutation burdens (TMBs), immune activation and specific drug resistance. This work highlights the significance of comprehensively examining post-transcriptional RNA modification genes. Conclusion: Here, we designed and verified an advanced forecasting model to reveal the underlying links between BC and RMPs and precisely predict the clinical outcomes of multivariate prognostic patterns for individuals.

Dissecting the roles of the Tuberin protein in the subcellular localization of the G2/M Cyclin, Cyclin B1.

Tuberin is a major component of the protein regulatory complex known as the Tuberous Sclerosis Complex and plays a crucial role in cell cycle progression and protein synthesis. Mutations in the Tuberin gene, TSC2, lead to the formation of benign tumors in many organ systems and causes the Tuberous Sclerosis Complex disorder. Genotypes ranging from point mutations to large deletions in the TSC2 gene have been clinically characterized with a wide range of phenotypes from skin tumors to large brain tumors. Our lab has previously demonstrated that Tuberin can directly bind and regulate the timing of nuclear transport of the G2/M cyclin, Cyclin B1. Herein we study the consequence of one clinically relevant truncation in the Tuberin protein on cell cycle function. We demonstrate that exogenous expression of a fragment of the N-term region of Tuberin alters the subcellular localization of Cyclin B1 and increases cell proliferation. This adds to our body of information about the residues within Tuberin responsible for regulating the cytoplasmic retention of Cyclin B1 and supports the phenotypic data seen in the clinic with Tuberous Sclerosis Complex patients harbouring similar large deletions in Tuberin.

Non-canonical anti-cancer, anti-metastatic, anti-angiogenic and immunomodulatory PDT potentials of water soluble phthalocyanine derivatives with imidazole groups and their intracellular mechanism of action

Cancer is currently a leading health issue globally. Chemotherapy is a prominent treatment method but due to undesired side effects t, there has been a need for novel less toxic approaches. Photodynamic therapy may be listed among the alternatives for efficient and potentially less detrimental applications of cancer therapy. Canonical photodynamic therapy (PDT) approach requires a light source with a specific wavelength of light, a non-toxic photosensitizer and molecular oxygen. PDT creates the desired effect by the photochemical reaction created through interaction of these components to create reactive oxygen species that will act on the cancer cells to enable anti-cancer activities. In our study we focus on non-canonical PDT application. In this approach we are not only aiming to eliminate cancer cells in the environment but also test the anti-metastatic, anti-angiogenic and possible immunomodulatory activities of the novel photosensitizers. Moreover, in our approach, we studied the intracellular pathways that are crucial for carcinogenesis, cell cycle, apoptosis, angiogenesis, metastasis and immune function to decipher the mechanism of the action for each compound. Reactive oxygen species based explanation was not valid in our study, hence it brings out a non canonical approach to PDT applications. Our results suggests that Phthalocyanine derivatives with imidazole groups can be effectively used against lung, colon, breast and prostate cancer while differentially effecting metastasis, angiogenesis, cell cycle, apoptosis and immune system cells’ activities. Based on the results, PDT application of these phthalocyanine derivatives can be an effective treatment option to replace chemotherapy to minimize the potential side effects.

FUCCItrack: An all-in-one software for single cell tracking and cell cycle analysis

Beyond the more conventional single-cell segmentation and tracking, single-cell cycle dynamics is gaining a growing interest in the field of cell biology. Thanks to sophisticated systems, such as the fluorescent ubiquitination-based cell cycle indicator (FUCCI), it is now possible to study cell proliferation, migration, changes in nuclear morphology and single cell cycle dynamics, quantitatively and in real time. In this work, we introduce FUCCItrack, an all-in-one, semi-automated software to segment, track and visualize FUCCI modified cell lines. A user-friendly complete graphical user interface is presented to record and quantitatively analyze both collective cell proliferation as well as single cell information, including migration and changes in nuclear or cell morphology as a function of cell cycle. To enable full control over the analysis, FUCCItrack also contains features for identification of errors and manual corrections.

Identification of Differentially Expressed Long Noncoding RNAs as Functional Biomarkers and Construction of Function Enrichment Network in Oral Squamous Cell Carcinoma.

Objective This study aims to find the novel lncRNAs closely related to the progression of oral squamous cell carcinoma (OSCC) by comprehensively analyzing microarray. Methods Chip dataset GSE84805 was downloaded from the Gene Expression Omnibus (GEO) database, lncRNA expression profiles of OSCC and paracancerous tissue were obtained, probes sequences reannotation was conducted, and differentially expressed lncRNAs (DELs) and differentially expressed genes (DEGs) were identified. Finally, these data were analyzed by constructing the lncRNA-function enrichment network. Results We found that 465 lncRNAs are differentially expressed consisting of 193 upregulated lncRNAs and 272 downregulated lncRNAs. Meanwhile, 811 DEGs were identified with 498 upregulated genes and 313 downregulated genes. Analysis of the lncRNA-function enrichment network showed that these aberrant lncRNAs may be related to focal adhesion, inflammatory response pathway, cell cycle, matrix metalloproteinases, and other biological functions. Also, we found that some key lncRNAs such as LINC00152 and HOXA11-AS have been shown to play an important role in tumor proliferation and migration. Conclusion The key lncRNAs may serve as potential molecular markers or therapeutic targets in OSCC formation and development. It can also help us to understand the molecular mechanism of occurrence and development in OSCC.

Abstract 5170: Coding and non-coding gene meta-features predict outcome in pediatric rhabdomyosarcomas

Abstract INTRODUCTION: Pediatric rhabdomyosarcoma (RMS) has varying outcomes, particularly in intermediate-risk disease (IR-RMS) due to the limited ability of clinical staging to accurately risk-stratify a large proportion of patients. This study aimed to identify prognostic signatures in IR-RMS, the clinical subgroup with the most heterogeneous outcomes, which can potentially improve risk stratification compared with routine clinicopathologic metrics. Signature performance was validated on an independent set of RMS patients. METHODS: Prospectively obtained primary tumor specimens from 80 IR-RMS patients on Children’s Oncology Group clinical trial protocols formed the training set. Tumors from 54 RMS patients across all clinical risk groups formed the validation set. Whole transcriptome profiling was performed using oligonucleotide microarrays employing nearly 1.4 million probe selection regions (PSRs) and used to derive weighted meta-features. Accuracies of protein-coding and non-coding meta-features to predict overall (OS) and event-free (EFS) survival were compared using areas under receiver operating characteristic curves. Associated biological processes were analyzed using curated pathway analysis tools. RESULTS: PAX-FKHR status was able to predict OS (p=0.041) and EFS (p=0.008) in the validation set, but not in the training set. Histologic subtype followed a similar predictive pattern. Cox regression on over 17,000 coding genes on the training set identified a prognostic 30-coding gene meta-feature (gMF; OS p=0.001, EFS p=0.012). A similar analysis on non-coding transcripts identified a 39-PSR meta-feature (ncMF; OS, EFS p&amp;lt;0.001). Both gMF and ncMF were able to predict OS and EFS (p≤0.023) in the validation cohort. Based on OS, predictive accuracy of ncMF was higher than gMF (96% vs. 71%, p&amp;lt;0.001). Analysis of biological processes using gMF showed enrichment for functions associated with musculoskeletal development and signaling pathways. Similar analysis of non-coding meta-features revealed enrichment for cellular assembly, cell cycle, apoptosis, and cancer-associated functions. CONCLUSIONS: A non-coding RNA meta-feature was able to better predict outcome in IR-RMS than a coding gene meta-feature, where most standard clinical prognosticators failed. The meta-features were independently validated in IR and non-IR RMS. This suggests that non-coding transcripts can regulate and determine RMS biology and aggressiveness, and be used as novel prognostic indicators. Citation Format: Anirban P. Mitra, Sheetal A. Mitra, Jonathan D. Buckley, Stephen X. Skapek, Douglas S. Hawkins, Timothy J. Triche. Coding and non-coding gene meta-features predict outcome in pediatric rhabdomyosarcomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5170.

LncRNA RP11-10A14.5: a potential prognosis biomarker for LUAD through regulation on proliferation and metastasis

Lung cancer is the malignancy most commonly seen worldwide. Emerging evidences indicated that lncRNAs may serve as a prognosis marker and play important role in NSCLC tumor biology. In this work, we analyzed the prognosis value of RP11-10A14.5 using TCGA and GEPIA database and expression profiles using PCR and FISH assay. The biological roles of RP11-10A14.5 in cell growth and invasion were determined by in vitro and in vivo experiments. Expression of RP11-10A14.5 is correlated with increased clinical stage and poor survival prognosis. In vitro experiments revealed that RP11-10A14.5 was widely expressed in lung cancer cell lines and mainly distributed in the cytoplasm and enhanced the growth, invasion and migration ability of NSCLC cell lines. Immunofluorescence assay suggested that RP11-10A14.5 may promote EMT by downregulating E-cadherin and upregulating N-cadherin and Vimentin. Flow cytometry results suggested that RP11-10A14.5 did not significantly affect cell cycle function, but could significantly inhibit apoptosis which may further enhance metastasis cell survival. In conclusion, RP11-10A14.5 is associated with clinical stage and poor survival outcome, may serve as a diagnosis and prognosis predictor for LUAD. Further, RP11-10A14.5 could promote LUAD cell growth and metastasis.

UHRF2 regulates cell cycle, epigenetics and gene expression to control the timing of retinal progenitor and ganglion cell differentiation.

Ubiquitin-like, containing PHD and RING finger domains 2 (UHRF2) regulates cell cycle and binds 5-hydroxymethylcytosine (5hmC) to promote completion of DNA demethylation. Uhrf2-/- mice are without gross phenotypic defects; however, the cell cycle and epigenetic regulatory functions of Uhrf2 during retinal tissue development are unclear. Retinal progenitor cells (RPCs) produce all retinal neurons and Müller glia in a predictable sequence controlled by the complex interplay between extrinsic signaling, cell cycle, epigenetic changes and cell-specific transcription factor activation. In this study, we find that UHRF2 accumulates in RPCs, and its conditional deletion from mouse RPCs reduced 5hmC, altered gene expressions and disrupted retinal cell proliferation and differentiation. Retinal ganglion cells were overproduced in Uhrf2-deficient retinae at the expense of VSX2+ RPCs. Most other cell types were transiently delayed in differentiation. Expression of each member of the Tet3/Uhrf2/Tdg active demethylation pathway was reduced in Uhrf2-deficient retinae, consistent with locally reduced 5hmC in their gene bodies. This study highlights a novel role of UHRF2 in controlling the transition from RPCs to differentiated cell by regulating cell cycle, epigenetic and gene expression decisions.

MYC Promotes Tyrosine Kinase Inhibitor Resistance in ROS1-Fusion-Positive Lung Cancer.

This study functionally characterizes MYC overexpression as a novel form of therapeutic resistance to ROS1 tyrosine kinase inhibitors in non-small cell lung cancer and proposes rational combination treatment strategies.

Genomic selection signatures in Brazilian sheep breeds reared in a tropical environment

The molecular and genetic effects of heat stress are not as well understood as physiological effects. Heat Stress response should be considered one component of gene network coordinated across various cells, tissues and systems. Its action seeks to minimize the effects of the environment on cellular functions. The detection of selection signatures can identify genes and mutations associated with phenotypic traits even if they are no longer segregating within the populations of interest. This paper looked at 48 sheep breeds (1988 animals), of which 649 animals are from 6 Brazilian breeds reared in a tropical environment. These animals were genotyped using the 50 K SNP Chip. We applied different detection methods (HapFLK and PCAdapt) to identify genomic regions with selection signals (selection signatures). Three groups of breeds were defined, and the first component showed a clear separation between Hair_Warm and Wool_Cold groups. The second component showed some divergence between Wool_Cold and Wool_Warm, with some Hair_Warm breeds located together with Wool_Warm. Hair Brazilian breeds were separated from the others in the first breed component, while the second component segregated European breeds from African and Asian breeds. The four genomic regions identified in chromosomes 2, 7, 11 and 16 harbor several genes related to a wide range of functions. These include production traits (such as milk, growth and reproduction), metabolism (fat and energy), stress response (including immune and inflammation), as well as cell cycle functions. These genomic regions can be a starting point for identifying gene mutations and selecting adapted animals, mainly in a climate change scenario. The locally adapted tropical sheep breeds can be an important genetic reservoir of these thermotolerance genes.

AB1, a novel protein targeting TP53 mutated GI tumors.

96 Background: The tumor suppressor gene TP53 is one of the most frequently deleted or mutated genes in gastrointestinal cancers. Normal p53 regulates several important proteins that control cell cycle, cell death, DNA damage/repair, stemness, differentiation and other key cellular functions. If the TP53 gene is damaged, tumor suppression is severely compromised. On the other hand, and downstream of p53, p21 a potent cyclin-dependent kinase inhibitor (CKI) protein binds and inhibitsthe activity of cyclin - CDK2, - CDK1, and - CDK4/6, thus functioning as a regulator ofcell cycle progression at G 1 and S phase. It can act as de facto p53 repair/ replacement mechanism. We have thus hypothesised that, if we were able to deliver wild type p21 into all p53 mutated cancer cells, it would have a possible therapeutic effect. Methods: We have constructed recombinantly a new fusion protein, named AB1, composed of a cell penetrating protein (antennapedia) ANTP and wild type p21 and tested it in in vitro and in vivo preclinical models prior to clinical studies. AB1 could also be constructed semi-synthetically by conjugating recombinant ANTP chemically to p21 protein. Results: AB1 penetrated and killed p53 mutated cancer cells but did not kill cells that did not have p53 mutations AB1 penetrated but did not kill p53- or p21- wild-type cells. AB1 was not immunogenic in normal New Zealand White rabbits. AB1 was more cytotoxic when administered with conventionally-used chemotherapeutic agents. Conclusions: We have generated a selectively cytotoxic fusion protein against p53 mutated GI cancers which is effective when used as a single agent but more so when used in combination with chemotherapy. The phaseI/II clinical trial will include eligible patients who have p53 mutated GI cancers

Naturally Sourced CDK Inhibitors and Current Trends in Structure-Based Synthetic Anticancer Drug Design by Crystallography.

Cyclin-Dependent Kinases (CDKs) are the chief regulators in cell proliferation; the kinase activities are largely regulated by their interactions with CDK Inhibitors (CKIs) and Cyclins. The association of different CDKs with CDKIs and Cyclins at the cell-cycle checkpoints of different stages of mitotic cell cycle function act more likely as the molecular switches that regulate different transcriptional events required for progression through the cell cycle. A fine balance in response to extracellular and intracellular signals is highly maintained in the orchestrated function of CDKs along with Cyclins and CDKIs for normal cell proliferation. This fine-tuning in mitotic cell cycle progression sometimes gets lost due to dysregulation of CDKs. The aberrant functioning of the CDKIs is therefore studied for its contributions as a vital hallmark of cancers. It has attracted our focus to maneuver cancer therapy. Hence, several synthetic CDKIs and their crystallography-based drug design have been explained to understand their mode of action with CDKs. Since most of the synthetic drugs function by inhibiting the CDK4/6 kinases by competitively binding to their ATP binding cleft, these synthetic drugs are reported to attack the normal, healthy growing cells adjacent to the cancer cells leading to the decrease in the life span of the cancer patients. The quest for traditional natural medicines may have a great impact on the treatment of cancer. Therefore, in the present studies, a search for naturally sourced CDK inhibitors has been briefly focused. Additionally, some synthetic crystallography-based drug design has been explained to elucidate different avenues to develop better anticancer chemotherapeutics, converting natural scaffolds into inhibitors of the CDK mediated abnormal signal transduction with lesser side effects.

P27, The Cell Cycle and Alzheimer´s Disease.

The cell cycle consists of successive events that lead to the generation of new cells. The cell cycle is regulated by different cyclins, cyclin-dependent kinases (CDKs) and their inhibitors, such as p27Kip1. At the nuclear level, p27Kip1 has the ability to control the evolution of different phases of the cell cycle and oppose cell cycle progression by binding to CDKs. In the cytoplasm, diverse functions have been described for p27Kip1, including microtubule remodeling, axonal transport and phagocytosis. In Alzheimer’s disease (AD), alterations to cycle events and a purported increase in neurogenesis have been described in the early disease process before significant pathological changes could be detected. However, most neurons cannot progress to complete their cell division and undergo apoptotic cell death. Increased levels of both the p27Kip1 levels and phosphorylation status have been described in AD. Increased levels of Aβ42, tau hyperphosphorylation or even altered insulin signals could lead to alterations in p27Kip1 post-transcriptional modifications, causing a disbalance between the levels and functions of p27Kip1 in the cytoplasm and nucleus, thus inducing an aberrant cell cycle re-entry and alteration of extra cell cycle functions. Further studies are needed to completely understand the role of p27Kip1 in AD and the therapeutic opportunities associated with the modulation of this target.

Combined overexpression of four transcription factors promotes effector T cell dedifferentiation toward early phenotypes.

Effector T cells, which are abundant but are short-lived after reinfusion into the body, are generally used for T-cell therapy, and antitumor immunity is typically not maintained over the long term. Genetic modification by early differentiated T cells and reinfusion has been shown to enhance antitumor immunity in vivo. This study overexpressed the characteristic transcription factors of differentiated early T cells by transfecting effector T cells with transcription factor recombinant lentivirus (S6 group: BCL6, EOMES, FOXP1, LEF1, TCF7, KLF7; S1 group: BCL6, EOMES, FOXP1, KLF7; S3 group: BCL6, EOMES, FOXP1, LEF1) to induce a sufficient number of effector T cells to dedifferentiate and optimize the transcription factor system. The results revealed that overexpression of early characteristic transcription factors in effector T cells upregulated the expression of early T cell differentiation markers (CCR7 and CD62L), with the S1 group having the highest expression level, while the rising trend of late differentiation marker (CD45RO) expression was suppressed. Moreover, the expression of early differentiation-related genes (ACTN1, CERS6, BCL2) was significantly increased, while the expression of late differentiation-related genes (KLRG-1) and effector function-related genes (GNLY, GZMB, PRF1) was significantly decreased; this difference in expression was more significant in the S1 group than in the other two experimental groups. The antiapoptotic ability of each experimental group was significantly enhanced, while the secretion ability of TNF-α and IFN-γ was weakened, with the effector cytokine secretion ability of the S1 group being the weakest. Transcriptomic analysis showed that the gene expression profile of each experimental group was significantly different from that of the control group, with differences in the gene expression pattern and number of differentially expressed genes in the S1 group compared with the other two experimental groups. The differentially expressed gene enrichment pathways were basically related to the cell cycle, cell division, and immune function. In conclusion, overexpression of early characteristic transcription factors in effector T cells induces their dedifferentiation, and induction of dedifferentiation by the S1 group may be more effective.