Cell Cycle Regulation in Treatment of Breast Cancer

TK1 expression influences pathogenicity by cell cycle progression, cellular migration, and cellular survival in HCC 1806 breast cancer cells

Breast cancer is the most common cancer diagnosis worldwide accounting for 1 out of every 8 cancer diagnoses. The elevated expression of Thymidine Kinase 1 (TK1) is associated with more aggressive tumor grades, including breast cancer. Recent studies indicate that TK1 may be involved in cancer pathogenesis; however, its direct involvement in breast cancer has not been identified. Here, we evaluate potential pathogenic effects of elevated TK1 expression by comparing HCC 1806 to HCC 1806 TK1-knockdown cancer cells (L133). Transcriptomic profiles of HCC 1806 and L133 cells showed cell cycle progression, apoptosis, and invasion as potential pathogenic pathways affected by TK1 expression. Subsequent in-vitro studies confirmed differences between HCC 1806 and L133 cells in cell cycle phase progression, cell survival, and cell migration. Expression comparison of several factors involved in these pathogenic pathways between HCC 1806 and L133 cells identified p21 and AKT3 transcripts were significantly affected by TK1 expression. Creation of a protein-protein interaction map of TK1 and the pathogenic factors we evaluated predict that the majority of factors evaluated either directly or indirectly interact with TK1. Our findings argue that TK1 elevation directly increases HCC 1806 cell pathogenicity and is likely occurring by p21- and AKT3-mediated mechanisms to promote cell cycle arrest, cellular migration, and cellular survival.

RPL11 promotes non-small cell lung cancer cell proliferation by regulating endoplasmic reticulum stress and cell autophagy

BACKGROUND

Abnormal biogenesis and ribosome free function of ribosomal proteins (RPs) is important for tumorgenesis and development. Ribosomal protein L11 (RPL11) is a component of ribosomal 60 S large subunit with different roles in different cancers. Here, we aimed to unravel the role of RPL11 in non-small cell lung cancer (NSCLC), especially those affecting cell proliferation.

METHODS

RPL11 expression in NCI-H1650, NCI-H1299, A549 and HCC827 and normal lung bronchial epithelial cells HBE was detected using western blotting. The function of RPL11 in NSCLC cells were determined by investigating cell viablity, colony formation and cell migration. Mechanism expoloration of RPL11 effect on NSCLC cells proliferation was explored using flow cytometry, and the effect on autophagy was investigated by the additon of autophagy inhibitor chloroquine (CQ) and endoplasmic reticulum stress (ERS) inhibitor tauroursodeoxycholic acid (TUDCA).

RESULTS

RPL11 was highly expressed in NSCLC cells. Extopic expression of RPL11 promoted NCI-H1299 and A549 cells proliferation, and migration, and promoted the transition from the G1 phase to the S phase of the cell cycle. Small RNA interference of RPL11 (siRNA) suppressed NCI-H1299 and A549 cells proliferation and migration and arrested the cell cycle in G0/G1 phase. Moreover, RPL11 promoted NSCLC cell proliferation by modulating autophagy and ERS. Expression levels of autophagy and ERS markers were induced by RPL11 overexpression and inhibited by siRPL11. CQ partially suppressed RPL11-induced A549 and NCI-H1299 proliferation: CQ addition reduced RPL11-induced cells viability and clone numbers and reversed the cell cycle process. ERS inhibitor (TUDCA) partially reversed RPL11-induced autophagy.

CONCLUSION

Taken together, RPL11 has a tumor-promoting role in NSCLC. It promotes the cell proliferation of NSCLC cells by regulating ERS and autophagy.

BAP31 Regulates Wnt Signaling to Modulate Cell Migration in Lung Cancer

B-cell receptor-associated protein 31 (BAP31) has been shown to overexpress in a wide range type of cancers. The present study aims to investigate the role of BAP31 on migration in lung cancer. Results showed that the migration of BAP31 knockdown cells was weaken than the control cells. Applying TGFβ to treat BAP31 knockdown cells could reduce cell migration. The enhancement on proliferation by TGFβ treatment was downregulated after BAP31 knockdown. The cell death and G0/G1 phase arrest was increased in the cells with TGFβ and BAP31 siRNA treatment when compared with TGFβ treatment alone. Gene expression analysis showed that Bax/Bcl2, MLKL and LC3 was upregulated in the cells with combinatorial treatment of TGFβ and BAP31 siRNA. In addition, BAP31 was shown to regulate multiple signaling pathways, especially for Wnt signaling. It found that BAP31 knockdown cells treated with TGFβ decreased β-catenin cytosolic expression and nuclear localization. Wnt signaling activator BIO could restore the downregulation of proliferation by BAP31 knockdown. This finding suggested that BAP31 regulated cancer cell migration is possibly involved with cell death mechanisms and Wnt signaling.

The cell cycle-related genes RHAMM, AURKA, TPX2, PLK1, and PLK4 are associated with the poor prognosis of breast cancer patients

Breast cancer is the third most common type of cancer diagnosed. Cell cycle is a complex but highly organized and controlled process, in which normal cells sense mitogenic growth signals that instruct them to enter and progress through their cell cycle. This process culminates in cell division generating two daughter cells with identical amounts of genetic material. Uncontrolled proliferation is one of the hallmarks of cancer. In this study, we analyzed the expression of the cell cycle-related genes receptor for hyaluronan (HA)-mediated motility (RHAMM), AURKA, TPX2, PLK1, and PLK4 and correlated them with the prognosis in a collective of 3952 breast cancer patients. A high messenger RNA expression of all studied genes correlated with a poor prognosis. Stratifying the patients according to the expression of hormonal receptors, we found that in patients with estrogen and progesterone receptor-positive and human epithelial growth factor receptor 2-negative tumors, and Luminal A and Luminal B tumors, the expression of the five analyzed genes correlates with worse survival. qPCR analysis of a panel of breast cancer cell lines representative of major molecular subtypes indicated a predominant expression in the luminal subtype. In vitro experiments showed that radiation influences the expression of the five analyzed genes both in luminal and triple-negative model cell lines. Functional analysis of MDA-MB-231 cells showed that small interfering RNA knockdown of PLK4 and TPX2 and pharmacological inhibition of PLK1 had an impact on the cell cycle and colony formation. Looking for a potential upstream regulation by microRNAs, we observed a differential expression of RHAMM, AURKA, TPX2, PLK1, and PLK4 after transfecting the MDA-MB-231 cells with three different microRNAs. Survival analysis of miR-34c-5p, miR-375, and miR-142-3p showed a different impact on the prognosis of breast cancer patients. Our study suggests that RHAMM, AURKA, TPX2, PLK1, and PLK4 can be used as potential targets for treatment or as a prognostic value in breast cancer patients.

Efficacy, Safety, and Tumor Marker Inhibition of Apatinib Combined with Conventional Chemotherapy Regimens for Patients with Advanced Triple-Negative Breast Cancer

Objective

Triple-negative breast cancer (TNBC) is an aggressive disease with highly invasive nature and poor outcomes. Due to the absence of specific treatment strategies for this tumor subgroup, patients with TNBC are treated with conventional therapeutics, frequently leading to systemic relapse. In this study, we sought to investigate apatinib combined with conventional chemotherapy regimens in treating patients with advanced TNBC concerning the efficacy, safety, expressions of tumor markers, and patient survival.

Methods

This is a prospective study including 150 cases of advanced TNBC who were randomly arranged into a conventional group and combined group, with 75 cases per group. The patients in the conventional group were treated with conventional chemotherapy, and those in the combined group were treated with apatinib combined with conventional chemotherapy. The peripheral blood was collected from each patient, and carcinoembryonic antigen (CEA), carbohydrate antigen 153 (CA153), and carbohydrate antigen 125 (CA125) were determined. The expressions of nuclear proliferation antigen marker (Ki67), β-catenin, and E-cadherin were determined in the biopsy collected from each patient.

Results

The objective remission rate (ORR) and disease control rate (DCR) (41.33% and 81.33%) in the combined group were notably higher than those in the conventional group (29.33% and 68.00%) (P < 0.05). After treatment, the serum levels of CEA, CA153, and CA125 and the expressions of Ki67 and β-catenin were declined, but the expression of E-cadherin was increased in both groups; the combined group exhibited lower serum levels of CEA, CA153, and CA125, and the expressions of Ki67 and β-catenin were concurrent with a higher expression of E-cadherin than the conventional group (P < 0.05). No significant difference was noted between the two groups regarding the occurrence of adverse reactions (P > 0.05). Improved progression-free survival (PFS) was observed in the combined group compared to the conventional group (P < 0.05.

Conclusion

These findings suggest that apatinib combined with conventional chemotherapy regimens confers a prolonged PFS for treating patients with advanced TNBC.

Induction of cell cycle arrest and apoptosis by CPUC002 through stabilization of p53 and suppression of STAT3 signaling pathway in multiple myeloma

Multiple myeloma has always been an important health problem in human beings due to its high morbidity, high mortality, and lack of effective therapeutic drugs. This study investigated the anticancer effect and mechanism of the newly synthesized small molecule compound CPUC002 on multiple myeloma. Our results confirmed that CPUC002 inhibited proliferation and induced G0/G1 cell cycle arrest in multiple myeloma cells. Moreover, CPUC002 also induced apoptosis by mitochondrial pathway and exogenous pathway. In mechanism, CPUC002 triggered apoptosis by stabilizing p53 in NCI-H929 cells which expressed wt-p53. Knockdown of p53 partially suppressed CPUC002-induced apoptosis. This suggests that there are other molecular mechanisms underlying CPUC002's antitumor effect. Further studies showed that the CPUC002 also inhibited the STAT3 signaling pathway, while knockdown of STAT3 abolished CPUC002-induced apoptosis and cell cycle arrest. In vivo, CPUC002 has significant antitumor activity through the same mechanism as our in vitro studies, and is highly safe in xenograft models. Together these findings indicate that CPUC002 induces apoptosis and G0/G1 cell cycle arrest in multiple myeloma cells by stabilizing p53 and inhibiting the STAT3 signaling pathway.

SSi6 promotes cell death by apoptosis through cell cycle arrest and inhibits migration and invasion of MDA-MB-231 human breast cancer cells

Triple-negative breast cancer subtype is the most aggressive type of breast cancer due to the lack of specific therapeutic targets, having limited treatment options, low survival prognosis and high recurrence rates. In this work, we describe the effects of a semisynthetic derivative of [6]-gingerol (6G) called SSi6, produced by the addition of a 2,4-dinitrophenylhydrazine reagent on several aspects of triple-negative breast cancer biology. Human breast cancer cell lines MDA-MB-231 and MCF-10A were used in the experiments. MTT assays were used to detect cell viability. Cell cycle and apoptosis assay were analyzed using flow cytometer Accuri C6 and analysis of proteins as retinoblastoma Rb and kinases Cdk4/6 were analyzed by western blotting. SSi6 induced cytotoxic effects on triple-negative breast cancer cells, with higher selectivity when compared to the non-tumor MCF-10A cells. In addition, SSi6 inhibited migration and invasion of triple-negative breast cancer cells and was able to arrest cell cycle at the G1-phase, mainly by decreasing Cdk4/6-Rb axis levels. Therefore, SSi6 provoked the induction of apoptosis in triple-negative breast cancer cells. SSi6 was more efficient in producing these effects, compared to the original 6G natural product. This study may contribute to a better understanding of the effects of natural and semisynthetic products on the in-vitro metastatic processes in the MDA-MB-231 triple-negative breast cancer cell line. Additional, it can be useful to understand the effects of chemical modifications on already effective natural compounds aiming at the improvement of their bioactive properties, such as in the increase of the cytotoxic selectivity against tumor cells, compared to non-tumor ones.

Thioalbamide, A Thioamidated Peptide from Amycolatopsis alba, Affects Tumor Growth and Stemness by Inducing Metabolic Dysfunction and Oxidative Stress

Thioalbamide, a thioamidated peptide biosynthesized by Amycolatopsis alba, is a thioviridamide-like molecule, and is part of a family of natural products representing a focus of biotechnological and pharmaceutical research in recent years due to their potent anti-proliferative and cytotoxic activities on malignant cells. Despite the high antitumor potential observed at nanomolar concentrations, the mechanisms underlying thioalbamide activity are still not known. In this work, the cellular effects induced by thioalbamide treatment on breast cancer cell lines were evaluated for the first time, highlighting the ability of this microbial natural peptide to induce mitochondrial dysfunction, oxidative stress, and apoptotic cell death. Furthermore, we demonstrate that thioalbamide can inhibit the propagation of cancer stem-like cells, which are strongly dependent on mitochondrial function and are responsible for chemotherapy resistance, metastasis, and tumor recurrence.

Bioinformatics analysis of differentially expressed genes in hepatocellular carcinoma cells exposed to Swertiamarin

Aim: To explore gene expression profiling in hepatocellular carcinoma (HCC) cells exposed to swertiamarin.

Methods: Cell viability, apoptosis and invasion were examined in HepG2 cells after swertiamarin treatment. Tumor growth of SK-Hep-1 cells xenografted in nude mice was monitored after swertiamarin treatment. Total RNA was isolated from HepG2 cells treated with swertiamarin for microarray analysis. The data of microarray were analyzed by bioinformatics.

Results: Swertiamarin treatment decreased the viability and invasion while increased the apoptosis of HepG2 cells, and significantly inhibited the growth of SK-Hep-1 cells xenografted in nude mice. Pathway and biological process analysis of differentially expressed genes (DEGs) in swertiamarin treated HepG2 cells showed that PI3k-Akt was the most significant regulated pathway. 47 targets of swertiamarin were predicted by CGBVS while 21 targets were predicted by 3NN. Notably, 8 targets were predicted as the targets of swertiamarin by both programs, including two prominent targets JUN and STAT3. A large range of DEGs induced by swertiamarin could be regulated by JUN and STAT3.

Conclusion: Swertiamarin treatment led to significant changes in the expression of a variety of genes that modulate cell survival, cell cycle progression, apoptosis, and invasion. Moreover, most of these genes can be clustered into pathway networks such as PI3K, JUN, STAT3, which are predicted targets of swertiamarin. Further confirmation of these targets will reveal the anti-tumor mechanisms of swertiamarin and facilitate the development of swertiamarin as a novel agent for cancer prevention and treatment.

Aberrant Regulation of RAD51 Promotes Resistance of Neoadjuvant Endocrine Therapy in ER-positive Breast Cancer

Breast cancer is one of the most common malignant cancers affecting females. Estrogen receptor (ER)-positive breast cancer is responsive to endocrine therapy. Although current therapies offer favorable prospects for improving survival, the development of resistance remains a severe problem. In this study, we explored the resistance mechanisms of ER-positive breast cancer to neoadjuvant endocrine therapy. Microarray data of GSE87411 contained 109 pairs of samples from Z1031 trial, including untreated samples and post-treated samples with neoadjuvant aromatase inhibitor (AI) therapy. The differentially expressed genes (DEGs) were obtained from two different comparisons: untreated samples versus post-treated samples with AIs, and post-treated samples sensitive versus resistant to AIs. Multiple bioinformatic methods were applied to evaluate biological function, protein-protein network and potential binding between target protein and aromatase inhibitor. Then, regulation of gene expression, DNA methylation and clinicopathological factors of breast cancer were further analyzed with TCGA data. From GSE87411 dataset, 30 overlapped DEGs were identified. Cell division was found to be the main function of overlapped DEGs by functional enrichment and gene ontology (GO) analysis. RAD51 recombinase (RAD51), a key protein of homologous recombination, was detected to interact with BReast CAncer genes 2 (BRCA2). Moreover, according to the docking simulation, RAD51 might potentially bind to AIs. Overexpressed RAD51 was associated with hypermethylation of BRCA2, resistance to AIs and poor overall survival of patients with ER-positive breast cancer. Furthermore, RAD51 was found to be a better indicator than MKI67 for predicting resistance in neoadjuvant setting. The results indicated that methylation of BRCA2 led to incomplete suppression on RAD51, which caused an increased expression of RAD51, subsequently AI-resistance and poor prognosis in ER-positive breast cancer. RAD51 could be a new candidate used as a predicative marker and therapeutic target in neoadjuvant endocrine treatment.

Identification and characterization of sexual dimorphism‑linked gene expression profile in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is sexually disparate in humans, with a significantly increased prevalence in males. The molecular mechanisms by which the inhibition or development of liver cancer are facilitated require further investigation with regard to sex factors affecting disease progression. In the present study, functional signatures of differentially expressed genes (DEGs) were screened in female and male tumors via bioinformatics analysis. The following gene chip expression profiles were downloaded from the Gene Expression Omnibus: GSE19665, GSE23342 and GSE9843. They comprised cancerous and non-cancerous tissue from patients with HCC and included critical sex features. Further evaluation of selected DEGs in the two sexual groups was performed via hierarchical clustering analysis. Venn diagram and functional protein-protein interaction (PPI) network analyses were performed. Survival analysis of patients with differences in gene expression levels was subsequently performed using the Kaplan-Meier Plotter database. Certain identified DEGs were common in female and male tumor samples, whereas others exhibited a sexually-biased expression profile. Gene Ontology revealed that the cell cycle module ‘biological process’ was enriched in tumors derived from both sexes, whereas the metabolic pathways and drug metabolism modules were only significantly enriched in cancer tissues from male subjects. A number of hub DEGs in the cell cycle and p53 signaling pathways were involved in significant protein-protein interaction (PPI) modules, including CDK1 and CCNB1. These DEGs were upregulated in tumors derived from female subjects compared with those derived from male subjects, and could be used as markers of poor prognosis in male patients. Other genes, such as CYP3A4 and SERPINA4, were identified in metabolic pathways, and were downregulated in male compared with female subjects. These genes were associated with a decreased survival rate. The data demonstrated that sex differences in physiology may regulate the levels of gene expression and/or activity, including gene function associated with oncogenesis and the outcomes of liver cancer. Additional surveys are required to explore in detail the molecular mechanisms underlying the differences in gene expression between the two sexes during the development of liver cancer.

Long non‑coding RNA FOXD2‑AS1/miR‑150‑5p/PFN2 axis regulates breast cancer malignancy and tumorigenesis

Breast cancer (BC) is a common cancer and leading cause of cancer‑associated mortality in women. Abnormal expression of long non‑coding RNA FOXD2 adjacent opposite strand RNA 1 (FOXD2‑AS1) was associated with the development of a number of tumors. However, whether FOXD2‑AS1 is dysregulated in BC and its underlying mechanisms remain unclear. In the present study, it was identified that FOXD2‑AS1 expression was upregulated in BC tissue, cell lines and sphere subpopulation. Additionally, the abnormal upregulation of FOXD2‑AS1 predicted poor prognosis in patients with BC. Furthermore, downregulation of FOXD2‑AS1 decreased cell proliferation, and migratory and invasive abilities in BC cells, and decreased the growth of transplanted tumors in vivo. Downregulation of FOXD2‑AS1 decreased the percentage of CD44 antigen+/signal transducer CD24- in breast cancer stem cell (BCSC) cells, and decreased the expression of numerous stem factors, including Nanog, octamer‑binding transcription factor 4 (Oct4), and sex determining region Y‑box 2 (SOX2), and inhibited the epithelial‑mesenchymal transition process. FOXD2‑AS1 was identified to be primarily located in the cytoplasm. Using bioinformatics analysis, a reporter gene assay and reverse transcription‑polymerase chain reaction assays, it was demonstrated that microRNA (miR)‑150‑5p was able to bind directly with the 3'‑untranslated region of FOXD2‑AS1 and PFN2 mRNA. miR‑150‑5p mimics decreased the cell proliferation, migration and invasion of BC cells. FOXD2‑AS1 knockdown significantly inhibited the miR‑150‑5p inhibitor‑induced increase in Nanog, Oct4 and SOX2 expression. The miR‑150‑5p inhibitor‑induced increase in N‑cadherin, and decrease in E‑cadherin and vimentin was inhibited by FOXD2‑AS1 knockdown. Profilin 2 (PFN2) expression was significantly upregulated in BC tissues. Additionally, the abnormal upregulation of PFN2 was associated with poor prognosis in patients with BC. FOXD2‑AS1 and PFN2 expression was positively correlated. Collectively, the present results demonstrated the role of the FOXD2‑AS1/miR‑150‑5p/PFN2 axis in the development of BC, and provides novel targets for the treatment of BC, and potential biomarkers for diagnosis and prognosis of BC.

USP18 promotes breast cancer growth by upregulating EGFR and activating the AKT/Skp2 pathway

Recent studies have suggested that ubiquitin-specific peptidase (USP)18 may act as an oncogene in various types of cancer. Although the role of USP18 in breast cancer cell lines has been elucidated, the underlying mechanisms and clinical role of USP18 in breast cancer are currently not well understood. The bioinformatics analysis and experimental results of the present study demonstrated that aberrant promoter methylation led to increased expression of USP18 in breast cancer. In addition, correlation analysis suggested that a negative correlation between methylation and USP18 mRNA expression was observed in The Cancer Genome Atlas database. USP18 promoted cell proliferation, colony formation and cell cycle progression in vitro. Furthermore, the Gene Set Enrichment Analysis results demonstrated that USP18 may be negatively associated with apoptosis in patients with breast cancer. Bioinformatics analysis results indicated that USP18 was also revealed to be associated with the protein kinase B (AKT) signaling pathway and mammary tumorigenesis in vivo. In addition, the results indicated that USP18 may promote the epidermal growth factor (EGF)-mediated EGF receptor (EGFR)/AKT/S‑phase kinase-associated protein 2 (Skp2) pathway by upregulating EGFR and Skp2 in a AKT/forkhead box O3-dependent manner in breast cancer. The results of bioinformatics analysis revealed that increased USP18 expression was associated with a higher TNM stage and unfavorable prognosis in clinical patients. USP18 was also significantly enhanced in patients with human epidermal growth factor receptor 2-positive breast cancer; furthermore, Kaplan‑Meier curve demonstrated that combining USP18 and Skp2 expression improved prognostic capability in breast cancer. Taken together, these results suggested that USP18 may serve a key role in breast cancer development by upregulating EGFR and subsequently activating the AKT/Skp2 feedback loop pathway. The role of USP18 in breast cancer provides a novel insight into the clinical application of the USP18/AKT/Skp2 pathway.

Plant-Derived Anticancer Agents: Lessons from the Pharmacology of Geniposide and Its Aglycone, Genipin

For centuries, plants have been exploited by mankind as sources of numerous cancer chemotherapeutic agents. Good examples of anticancer compounds of clinical significance today include the taxanes (e.g., taxol), vincristine, vinblastine, and the podophyllotoxin analogues that all trace their origin to higher plants. While all these drugs, along with the various other available therapeutic options, brought some relief in cancer management, a real breakthrough or cure has not yet been achieved. This critical review is a reflection on the lessons learnt from decades of research on the iridoid glycoside geniposide and its aglycone, genipin, which are currently used as gold standard reference compounds in cancer studies. Their effects on tumour development (carcinogenesis), cancer cell survival, and death, with particular emphasis on their mechanisms of actions, are discussed. Particular attention is also given to mechanisms related to the dual pro-oxidant and antioxidant effects of these compounds, the mitochondrial mechanism of cancer cell killing through reactive oxygen species (ROS), including that generated through the uncoupling protein-2 (UCP-2), the inflammatory mechanism, and cell cycle regulation. The implications of various studies for the evaluation of glycosidic and aglycone forms of natural products in vitro and in vivo through pharmacokinetic scrutiny are also addressed.